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DIGGING INTO D8 AND R8 @JakeWharton

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$

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$ export ANDROID_HOME=/path/to/my/sdk

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$ export ANDROID_HOME=/path/to/my/sdk
 
 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git

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$ export ANDROID_HOME=/path/to/my/sdk
 
 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git Cloning into 'depot_tools'...
 remote: Sending approximately 20.90 MiB ...
 remote: Total 27643 (delta 19810), reused 27643 (delta 19810)
 Receiving objects: 100% (27643/27643), 20.90 MiB | 9.97 MiB/s, done.
 Resolving deltas: 100% (19810/19810), done.

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$ export ANDROID_HOME=/path/to/my/sdk
 
 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git Cloning into 'depot_tools'...
 remote: Sending approximately 20.90 MiB ...
 remote: Total 27643 (delta 19810), reused 27643 (delta 19810)
 Receiving objects: 100% (27643/27643), 20.90 MiB | 9.97 MiB/s, done.
 Resolving deltas: 100% (19810/19810), done.
 
 $ export PATH=$PATH:`pwd`/depot_tools

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$ export ANDROID_HOME=/path/to/my/sdk
 
 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git Cloning into 'depot_tools'...
 remote: Sending approximately 20.90 MiB ...
 remote: Total 27643 (delta 19810), reused 27643 (delta 19810)
 Receiving objects: 100% (27643/27643), 20.90 MiB | 9.97 MiB/s, done.
 Resolving deltas: 100% (19810/19810), done.
 
 $ export PATH=$PATH:`pwd`/depot_tools
 
 $ git clone https://r8.googlesource.com/r8

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$ export ANDROID_HOME=/path/to/my/sdk
 
 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git Cloning into 'depot_tools'...
 remote: Sending approximately 20.90 MiB ...
 remote: Total 27643 (delta 19810), reused 27643 (delta 19810)
 Receiving objects: 100% (27643/27643), 20.90 MiB | 9.97 MiB/s, done.
 Resolving deltas: 100% (19810/19810), done.
 
 $ export PATH=$PATH:`pwd`/depot_tools
 
 $ git clone https://r8.googlesource.com/r8 Cloning into 'r8'...
 remote: Sending approximately 21.71 MiB ...
 remote: Counting objects: 67, done
 remote: Total 56838 (delta 23158), reused 56838 (delta 23158)
 Receiving objects: 100% (56838/56838), 21.71 MiB | 10.21 MiB/s, done.
 Resolving deltas: 100% (23158/23158), done.

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 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git Cloning into 'depot_tools'...
 remote: Sending approximately 20.90 MiB ...
 remote: Total 27643 (delta 19810), reused 27643 (delta 19810)
 Receiving objects: 100% (27643/27643), 20.90 MiB | 9.97 MiB/s, done.
 Resolving deltas: 100% (19810/19810), done.
 
 $ export PATH=$PATH:`pwd`/depot_tools
 
 $ git clone https://r8.googlesource.com/r8 Cloning into 'r8'...
 remote: Sending approximately 21.71 MiB ...
 remote: Counting objects: 67, done
 remote: Total 56838 (delta 23158), reused 56838 (delta 23158)
 Receiving objects: 100% (56838/56838), 21.71 MiB | 10.21 MiB/s, done.
 Resolving deltas: 100% (23158/23158), done.
 
 $ cd r8

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Cloning into 'depot_tools'...
 remote: Sending approximately 20.90 MiB ...
 remote: Total 27643 (delta 19810), reused 27643 (delta 19810)
 Receiving objects: 100% (27643/27643), 20.90 MiB | 9.97 MiB/s, done.
 Resolving deltas: 100% (19810/19810), done.
 
 $ export PATH=$PATH:`pwd`/depot_tools
 
 $ git clone https://r8.googlesource.com/r8 Cloning into 'r8'...
 remote: Sending approximately 21.71 MiB ...
 remote: Counting objects: 67, done
 remote: Total 56838 (delta 23158), reused 56838 (delta 23158)
 Receiving objects: 100% (56838/56838), 21.71 MiB | 10.21 MiB/s, done.
 Resolving deltas: 100% (23158/23158), done.
 
 $ cd r8
 
 $ tools/gradle.py d8 r8

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 $ git clone https://r8.googlesource.com/r8 Cloning into 'r8'...
 remote: Sending approximately 21.71 MiB ...
 remote: Counting objects: 67, done
 remote: Total 56838 (delta 23158), reused 56838 (delta 23158)
 Receiving objects: 100% (56838/56838), 21.71 MiB | 10.21 MiB/s, done.
 Resolving deltas: 100% (23158/23158), done.
 
 $ cd r8
 
 $ tools/gradle.py d8 r8 (… gradle output removed …)
 :R8
 :D8
 
 BUILD SUCCESSFUL
 
 Total time: 28.471 secs

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Cloning into 'r8'...
 remote: Sending approximately 21.71 MiB ...
 remote: Counting objects: 67, done
 remote: Total 56838 (delta 23158), reused 56838 (delta 23158)
 Receiving objects: 100% (56838/56838), 21.71 MiB | 10.21 MiB/s, done.
 Resolving deltas: 100% (23158/23158), done.
 
 $ cd r8
 
 $ tools/gradle.py d8 r8 (… gradle output removed …)
 :R8
 :D8
 
 BUILD SUCCESSFUL
 
 Total time: 28.471 secs
 
 $ export R8_HOME=`pwd`

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dx compilers sources libraries transforms

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$

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$ cat Java8.java

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$ cat Java8.java class Java8 { interface Consumer { void accept(T value); } public static void main(String... args) { load(s -> System.out.println(s)); } private static void load(Consumer c) { c.accept("Hello!"); } }

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$ cat Java8.java class Java8 { interface Consumer { void accept(T value); }W public static void main(String... args) { load(s -> System.out.println(s)); }X private static void load(Consumer c) { c.accept("Hello!"); }Y }Z
 
 $ javac *.java

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$ cat Java8.java class Java8 { interface Consumer { void accept(T value); }W public static void main(String... args) { load(s -> System.out.println(s)); }X private static void load(Consumer c) { c.accept("Hello!"); }Y }Z
 
 $ javac *.java
 
 $ ls

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$ cat Java8.java class Java8 { interface Consumer { void accept(T value); }W public static void main(String... args) { load(s -> System.out.println(s)); }X private static void load(Consumer c) { c.accept("Hello!"); }Y }Z
 
 $ javac *.java
 
 $ ls Java8.java Java8.class Java8$Consumer.class

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interface Consumer { void accept(T value); }W public static void main(String... args) { load(s -> System.out.println(s)); }X private static void load(Consumer c) { c.accept("Hello!"); }Y }Z
 
 $ javac *.java
 
 $ ls Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class

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load(s -> System.out.println(s)); }X private static void load(Consumer c) { c.accept("Hello!"); }Y }Z
 
 $ javac *.java
 
 $ ls Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class Uncaught translation error: com.android.dx.cf.code.SimException:
 ERROR in Java8.main:([Ljava/lang/String;)V:
 invalid opcode ba - invokedynamic requires --min-sdk-version >= 26
 (currently 13)
 1 error; aborting

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dx compilers sources libraries transforms

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Desugar dx compilers sources libraries transforms

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Desugar dx compilers sources libraries transforms

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Desugar D8 compilers sources libraries transforms

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D8 compilers sources libraries transforms Desugar

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Desugar D8 compilers sources libraries transforms

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load(s -> System.out.println(s)); }X private static void load(Consumer c) { c.accept("Hello!"); }Y }Z
 
 $ javac *.java
 
 $ ls Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class Uncaught translation error: com.android.dx.cf.code.SimException:
 ERROR in Java8.main:([Ljava/lang/String;)V:
 invalid opcode ba - invokedynamic requires --min-sdk-version >= 26
 (currently 13)
 1 error; aborting

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}Z
 
 $ javac *.java
 
 $ ls Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class Uncaught translation error: com.android.dx.cf.code.SimException:
 ERROR in Java8.main:([Ljava/lang/String;)V:
 invalid opcode ba - invokedynamic requires --min-sdk-version >= 26
 (currently 13)
 1 error; aborting
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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 $ ls Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class Uncaught translation error: com.android.dx.cf.code.SimException:
 ERROR in Java8.main:([Ljava/lang/String;)V:
 invalid opcode ba - invokedynamic requires --min-sdk-version >= 26
 (currently 13)
 1 error; aborting
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ ls Java8.java Java8.class Java8$Consumer.class classes.dex

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Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class Uncaught translation error: com.android.dx.cf.code.SimException:
 ERROR in Java8.main:([Ljava/lang/String;)V:
 invalid opcode ba - invokedynamic requires --min-sdk-version >= 26
 (currently 13)
 1 error; aborting
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ ls Java8.java Java8.class Java8$Consumer.class classes.dex $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex Class #0 - Class descriptor : 'LJava8$Consumer;' Access flags : 0x0600 (INTERFACE ABSTRACT) Superclass : 'Ljava/lang/Object;' Interfaces - Static fields - Instance fields - Direct methods - Virtual methods - #0 : (in LJava8$Consumer;) name : 'accept' type : '(Ljava/lang/Object;)V' access : 0x0401 (PUBLIC ABSTRACT) code : (none) source_file_idx : 14 (Lambda.java) Class #1 - Class descriptor : 'LJava8;' Access flags : 0x0000 () Superclass : 'Ljava/lang/Object;' Interfaces - Static fields - Instance fields - Direct methods - #0 : (in LJava8;) name : '' type : '()V' access : 0x10000 (CONSTRUCTOR) code - registers : 1 ins : 1 outs : 1 insns size : 4 16-bit code units 000288: |[000288] Java8.:()V 000298: 7010 0900 0000 |0000: invoke-direct {v0}, Ljava/lang/Object;.:()V // method@0009 00029e: 0e00 |0003: return-void catches : (none) positions : 0x0000 line=1 locals : 0x0000 - 0x0004 reg=0 this LJava8; #1 : (in LJava8;) name : 'lambda$main$0' type : '(Ljava/lang/String;)V' access : 0x1008 (STATIC SYNTHETIC) code - registers : 2 ins : 1 outs : 2 insns size : 6 16-bit code units 0002a0: |[0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V 0002b0: 6200 0100 |0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream; // field@0001 0002b4: 6e20 0800 1000 |0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V // method@0008 0002ba: 0e00 |0005: return-void catches : (none) positions : 0x0000 line=7 locals : #2 : (in LJava8;) name : 'load' type : '(LJava8$Consumer;)V' access : 0x0009 (PUBLIC STATIC) code - registers : 2 ins : 1 outs : 2 insns size : 6 16-bit code units 0002bc: |[0002bc] Java8.load:(LJava8$Consumer;)V 0002cc: 1a00 0800 |0000: const-string v0, "Hello!" // string@0008 0002d0: 7220 0300 0100 |0002: invoke-interface {v1, v0}, LJava8$Consumer;.accept:(Ljava/lang/Object;)V // method@0003 0002d6: 0e00 |0005: return-void catches : (none) positions : 0x0002 line=13 locals : #3 : (in LJava8;) name : 'main' type : '([Ljava/lang/String;)V' access : 0x0089 (PUBLIC STATIC VARARGS) code - registers : 1 ins : 1 outs : 1 insns size : 6 16-bit code units 0002d8: |[0002d8] Java8.main:([Ljava/lang/String;)V 0002e8: 6200 0000 |0000: sget-object v0, L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;.INSTANCE:L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA; // field@0000 0002ec: 7110 0600 0000 |0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V // method@0006 0002f2: 0e00 |0005: return-void catches : (none) positions : 0x0000 line=7 locals : Virtual methods - source_file_idx : 14 (Lambda.java) Class #2 - Class descriptor : 'L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;' Access flags : 0x1011 (PUBLIC FINAL SYNTHETIC) Superclass : 'Ljava/lang/Object;' Interfaces - #0 : 'LJava8$Consumer;' Static fields - #0 : (in L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;) name : 'INSTANCE' type : 'L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;' access : 0x1019 (PUBLIC STATIC FINAL SYNTHETIC) Instance fields - Direct methods - #0 : (in L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;) name : '' type : '()V' access : 0x11008 (STATIC SYNTHETIC CONSTRUCTOR) code - registers : 1 ins : 0 outs : 1 insns size : 8 16-bit code units 000234: |[000234] -..Lambda.Java8.ZLMFZvUeLmahhYBQbdt-2RNqTMA.:()V 000244: 2200 0000 |0000: new-instance v0, L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA; // type@0000 000248: 7010 0100 0000 |0002: invoke-direct {v0}, L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;.:()V // method@0001 00024e: 6900 0000 |0005: sput-object v0, L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;.INSTANCE:L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA; // field@0000 000252: 0e00 |0007: return-void catches : (none) positions : locals : #1 : (in L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;) name : '' type : '()V' access : 0x11002 (PRIVATE SYNTHETIC CONSTRUCTOR) code - registers : 1 ins : 1 outs : 1 insns size : 4 16-bit code units 000254: |[000254] -..Lambda.Java8.ZLMFZvUeLmahhYBQbdt-2RNqTMA.:()V 000264: 7010 0900 0000 |0000: invoke-direct {v0}, Ljava/lang/Object;.:()V // method@0009 00026a: 0e00 |0003: return-void catches : (none) positions : locals : Virtual methods - #0 : (in L-$$Lambda$Java8$ZLMFZvUeLmahhYBQbdt-2RNqTMA;) name : 'accept' type : '(Ljava/lang/Object;)V' access : 0x0011 (PUBLIC FINAL) code - registers : 2 ins : 2 outs : 1 insns size : 6 16-bit code units 00026c: |[00026c] -..Lambda.Java8.ZLMFZvUeLmahhYBQbdt-2RNqTMA.accept:(Ljava/lang/Object;)V 00027c: 1f01 0900 |0000: check-cast v1, Ljava/lang/String; // type@0009 000280: 7110 0500 0100 |0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V // method@0005 000286: 0e00 |0005: return-void catches : (none) positions : locals : source_file_idx : 28 (lambda) + /Users/jakew/Library/Android/sdk/build-tools/28.0.2/dexdump -d r8.dex Processing 'r8.dex'... Opened 'r8.dex', DEX version '035' Class #0 - Class descriptor : 'LJava8;' Access flags : 0x0000 () Superclass : 'Ljava/lang/Object;' Interfaces - Static fields - Instance fields - Direct methods - #0 : (in LJava8;) name : 'lambda$main$0' type : '(Ljava/lang/String;)V' access : 0x1008 (STATIC SYNTHETIC) code - registers : 2 ins : 1 outs : 2 insns size : 6 16-bit code units 000120: |[000120] Java8.lambda$main$0:(Ljava/lang/String;)V 000130: 6200 0000 |0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream; // field@0000 000134: 6e20 0200 1000 |0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V // method@0002 00013a: 0e00 |0005: return-void catches : (none) positions : 0x0000 line=1 locals : #1 : (in LJava8;) name : 'main' type : '([Ljava/lang/String;)V' access : 0x0089 (PUBLIC STATIC VARARGS) code - registers : 1 ins : 1 outs : 1 insns size : 8 16-bit code units 00013c: |[00013c] Java8.main:([Ljava/lang/String;)V 00014c: 1a00 0100 |0000: const-string v0, "Hello!" // string@0001 000150: 1f00 0300 |0002: check-cast v0, Ljava/lang/String; // type@0003 000154: 7110 0000 0000 |0004: invoke-static {v0}, LJava8;.lambda$main$0:(Ljava/lang/String;)V // method@0000 00015a: 0e00 |0007: return-void catches : (none) positions : locals : Virtual methods - source_file_idx : 0 ()

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Java8.java Java8.class Java8$Consumer.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dx --dex --output . *.class Uncaught translation error: com.android.dx.cf.code.SimException:
 ERROR in Java8.main:([Ljava/lang/String;)V:
 invalid opcode ba - invokedynamic requires --min-sdk-version >= 26
 (currently 13)
 1 error; aborting $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ ls Java8.java Java8.class Java8$Consumer.class classes.dex $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002d8] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, LJava8$1;.INSTANCE:LJava8$1;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: return-void
 
 [0002a0] Java8.lambda$main$0:(Ljava/lang/String;)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0005: return-void
 
 [000234] Java8$1.:()V
 0000: new-instance v0, LJava8$1;
 0002: invoke-direct {v0}, LJava8$1;.:()V
 0005: sput-object v0, LJava8$1;.INSTANCE:LJava8;
 0007: return-void
 
 [00026c] Java8$1.accept:(Ljava/lang/Object;)V
 0000: check-cast v1, Ljava/lang/String;
 0002: invoke-static {v1}, LJava8;.lambda$main$0:(Ljava/lang/String;)V
 0005: return-void

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(s -> lambda$main$0(s)); }X static void lambda$main$0(String s) { System.out.println(s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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s -> class Java8$1 implements Consumer { @Override public void accept(String s) { Java8.lambda$main$0(s); }Y }Z class Java8 { public static void main(String... args) { load(new Java8$1()); }X static void lambda$main$0(String s) { System.out.println(s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8$1 implements Consumer { static final Java8$1 INSTANCE = new Java8$1(); @Override public void accept(String s) { Java8.lambda$main$0(s); }Y }Z class Java8 { public static void main(String... args) { load(Java8$1.INSTANCE); }X static void lambda$main$0(String s) { System.out.println(s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8$1 implements Consumer { static final Java8$1 INSTANCE = new Java8$1(); @Override public void accept(String s) { Java8.lambda$main$0(s); }Y }Z class Java8 { public static void main(String... args) { load(Java8$1.INSTANCE); }X static void lambda$main$0(String s) { System.out.println(s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY implements Consumer { static final -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY INSTANCE = new -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY(); @Override public void accept(String s) { Java8.lambda$main$0(s); }Y }Z class Java8 { public static void main(String... args) { load(-$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY.INSTANCE); }X static void lambda$main$0(String s) { System.out.println(s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY implements Consumer { static final -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY INSTANCE = new -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY(); @Override public void accept(String s) { Java8.lambda$main$0(s); }Y }Z class Java8 { public static void main(String... args) { load(-$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY.INSTANCE); }X static void lambda$main$0(String s) { System.out.println(s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(s -> System.out.println(args[0] + " " + s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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s -> class -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY implements Consumer { private final String[] args; -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY(String[] args) { this.args = args; } @Override public void accept(String s) { Java8.lambda$main$0(args, s); } } class Java8 { public static void main(String... args) { load(new -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY(args)); }X static void lambda$main$0(String[] args, String s) { System.out.println(args[0] + " " + s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY implements Consumer { private final String[] args; -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY(String[] args) { this.args = args; } @Override public void accept(String s) { Java8.lambda$main$0(args, s); } } class Lambda { public static void main(String... args) { load(new -$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY(args)); }X static void lambda$main$0(String[] args, String s) { System.out.println(args[0] + " " + s); }A interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); // other code… load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); // other code… load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); // other code… load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); // other code… load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00039c] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, L-$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY;.INSTANCE
 :L-$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: sget-object v0, L-$$Lambda$Java8$6t081pcxeVAk2jXN7bDL1QxzIIU;.INSTANCE
 :L-$$Lambda$Java8$6t081pcxeVAk2jXN7bDL1QxzIIU;
 0007: invoke-static {v0}, LJava;.load:(LJava8$Consumer;)V
 000a: return-void

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00039c] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v0, L-$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY;.INSTANCE
 :L-$$Lambda$Java8$fcyZxanqBZSHC_nf-noKh-e3bnY;
 0002: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0005: sget-object v0, L-$$Lambda$Java8$6t081pcxeVAk2jXN7bDL1QxzIIU;.INSTANCE
 :L-$$Lambda$Java8$6t081pcxeVAk2jXN7bDL1QxzIIU;
 0007: invoke-static {v0}, LJava;.load:(LJava8$Consumer;)V
 000a: return-void

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class Java8 { public static void main(String... args) { load(s -> System.out.println(s)); // other code… load(s -> System.out.println(s)); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(System.out::println); // other code… load(System.out::println); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z

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class Java8 { public static void main(String... args) { load(System.out::println); // other code… load(System.out::println); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java

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class Java8 { public static void main(String... args) { load(System.out::println); // other code… load(System.out::println); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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class Java8 { public static void main(String... args) { load(System.out::println); // other code… load(System.out::println); }X interface Consumer { void accept(T value); }W private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002bc] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 0004: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0007: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 000a: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000c: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 000e: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0011: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0014: return-void

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002bc] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 0004: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0007: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 000a: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000c: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 000e: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0011: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0014: return-void

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002bc] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 0004: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0007: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 000a: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000c: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 000e: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0011: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0014: return-void

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002bc] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 0004: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0007: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 000a: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000c: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 000e: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0011: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0014: return-void

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private static void load(Consumer c) { c.accept("Hello!"); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [0002bc] Java8.main:([Ljava/lang/String;)V
 0000: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 0004: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0007: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 000a: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000c: new-instance v0, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;
 000e: invoke-direct {v0, v1}, L-$$Lambda$3a8cOTS_BDddTs3zL5A7slX7lPc;.:(Ljava/io/PrintStream;)V
 0011: invoke-static {v0}, LJava8;.load:(LJava8$Consumer;)V
 0014: return-void

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$ cat Not.java

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$ cat Not.java class Not { static void print(int value) { System.out.println(~value); }Y }Z

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$ cat Not.java class Not { static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java

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$ cat Not.java class Not { static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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$ cat Not.java class Not { static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void 00010100 xor 11111111

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void 00010100 xor 11111111 11101011 =

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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static void print(int value) { System.out.println(~value); }Y }Z $ javac *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void

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$ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class

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$ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class

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$ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class

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--release \
 --output . \
 *.class $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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[000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: xor-int/lit8 v1, v1, #int -1
 0004: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0007: return-void
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --min-api 21
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000134] Not.print:(I)V
 0000: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0002: not-int v1, v1
 0003: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(I)V
 0006: return-void

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D8 compilers sources libraries transforms

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ProGuard D8 compilers sources libraries transforms

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D8 compilers sources libraries transforms ProGuard

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ProGuard compilers sources libraries transforms R8

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$ cat Greeter.kt

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$ cat Greeter.kt fun main(vararg args: String) { println(Greeter.hello("Droidcon")) } class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) } }

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$ cat Greeter.kt fun main(vararg args: String) { println(Greeter.hello("Droidcon")) } class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) } }

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$ cat Greeter.kt fun main(vararg args: String) { println(Greeter.hello("Droidcon")) } class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) } }

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$ cat Greeter.kt fun main(vararg args: String) { println(Greeter.hello("Droidcon")) } class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) } }

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$ cat Greeter.kt fun main(vararg args: String) { println(Greeter.hello("Droidcon")) } class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) } }

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$ cat Greeter.kt fun main(vararg args: String) { println(Greeter.hello("Droidcon")) }Z class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }Y }Z
 
 $ kotlinc -classpath $ANDROID_HOME/platforms/android-28/android.jar *.kt

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fun main(vararg args: String) { println(Greeter.hello("Droidcon")) }Z class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }Y }Z
 
 $ kotlinc -classpath $ANDROID_HOME/platforms/android-28/android.jar *.kt
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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println(Greeter.hello("Droidcon")) }Z class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }Y }Z
 
 $ kotlinc -classpath $ANDROID_HOME/platforms/android-28/android.jar *.kt
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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--lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 [000314] Greeter.Companion.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3

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--lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 [000314] Greeter.Companion.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3

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--lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 [000314] Greeter.Companion.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3

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--lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 [000314] Greeter.Companion.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3

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--output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 [000314] Greeter.Companion.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt

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0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 [000314] Greeter.Companion.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate

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0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v3}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v3
 000b: return-object v3
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }B }A

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }B }A public final class Greeter { public static final Companion Companion = new Companion(); private final String greeting; public Greeter(String greeting) { this.greeting = greeting; } public String getGreeting() { return greeting; } public String greet(String name) { return greeting + ", " + name; } public static final class Companion { private Companion() {} public String hello(String name) { return new Greeter("Hello").greet(name); }X }Y }Z

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }B }A public final class Greeter { private final String greeting; public Greeter(String greeting) { this.greeting = greeting; } public String getGreeting() { return greeting; } public String greet(String name) { return greeting + ", " + name; } public static String hello(String name) { return new Greeter("Hello").greet(name); }X }Z

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { fun hello(name: String) = Greeter("Hello").greet(name) }B }A

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { @JvmStatic fun hello(name: String) = Greeter("Hello").greet(name) }B }A

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { @JvmStatic fun hello(name: String) = Greeter("Hello").greet(name) } }
 
 $ kotlinc -classpath $ANDROID_HOME/platforms/android-28/android.jar *.kt

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { @JvmStatic fun hello(name: String) = Greeter("Hello").greet(name) }B }A
 
 $ kotlinc -classpath $ANDROID_HOME/platforms/android-28/android.jar *.kt
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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class Greeter(val greeting: String) { fun greet(name: String) = "$greeting, $name!" companion object { @JvmStatic fun hello(name: String) = Greeter("Hello").greet(name) }B }A
 
 $ kotlinc -classpath $ANDROID_HOME/platforms/android-28/android.jar *.kt
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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--output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1

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--output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1

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--output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1

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--output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1

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--output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000370] GreeterKt.main:([Ljava/lang/String;)V
 0000: sget-object v1, LGreeter;.Companion:LGreeter$Companion;
 0002: const-string v0, "Droidcon"
 0005: invoke-virtual {v1, v0}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1

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0008: move-result-object v1
 0009: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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000b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000e: return-void
 
 #2 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [00042c] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: sget-object v0, LGreeter;.Companion:LGreeter$Companion;
 0002: invoke-virtual {v0, v1}, LGreeter$Companion;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: return-object v1
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000234] GreeterKt.main:([Ljava/lang/String;)V
 0000: const-string v1, "Droidcon" // string@0004
 0002: invoke-static {v1}, LGreeter;.hello:(Ljava/lang/String;)Ljava/lang/String;
 0005: move-result-object v1
 0006: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 000b: return-void
 
 #1 : (in LGreeter;)
 name : 'hello'
 type : '(Ljava/lang/String;)Ljava/lang/String;'
 access : 0x0019 (PUBLIC STATIC FINAL)
 code -
 [0002bc] Greeter.hello:(Ljava/lang/String;)Ljava/lang/String;
 0000: new-instance v0, LGreeter;
 0002: const-string v1, "Hello"
 0004: invoke-direct {v0, v1}, LGreeter;.:(Ljava/lang/String;)V
 0007: invoke-virtual {v0, v2}, LGreeter;.greet:(Ljava/lang/String;)Ljava/lang/String;
 000a: move-result-object v2
 000b: return-object v2

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@Module object HelloGreeterModule { @Provides fun greeter() = Greeter("Hello") }

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public final class Thing { public static final Thing INSTANCE = new Thing(); private Thing() { } public void doThing() { // … } }

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$ cat Nulls.kt

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) }

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) }

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) }

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) }

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) }

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) } Z $ kotlinc -classpath kotlin-stdlib-1.2.61.jar *.kt

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$ cat Nulls.kt fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) } Z $ kotlinc -classpath kotlin-stdlib-1.2.61.jar *.kt $ java -jar $R8_HOME/build/libs/d8.jar \ --lib $ANDROID_HOME/platforms/android-28/android.jar \ --lib kotlin-stdlib-1.2.61.jar \ --release \ --output . \ *.class

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fun coalesce(a: T?, b: T?): T? = a ?: b fun firstOrSecond(first: String?, second: String): String = coalesce(first, second) ?: throw AssertionError() fun main(vararg args: String) { println(firstOrSecond(null, "two")) println(firstOrSecond("one", "two")) } Z $ kotlinc -classpath kotlin-stdlib-1.2.61.jar *.kt $ java -jar $R8_HOME/build/libs/d8.jar \ --lib $ANDROID_HOME/platforms/android-28/android.jar \ --lib kotlin-stdlib-1.2.61.jar \ --release \ --output . \ *.class 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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*.class 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000208] NullsKt.coalesce:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 0000: if-eqz v0, 0003
 0002: goto 0004
 0003: move-object v0, v1
 0004: return-object v0
 
 [000224] NullsKt.firstOrSecond:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
 0000: const-string v0, "second"
 0002: invoke-static {v2, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: invoke-static {v1, v2}, LNullsKt;.coalesce:(LString;LString;)Ljava/lang/String;
 0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V


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*.class 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000208] NullsKt.coalesce:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 0000: if-eqz v0, 0003
 0002: goto 0004
 0003: move-object v0, v1
 0004: return-object v0
 
 [000224] NullsKt.firstOrSecond:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
 0000: const-string v0, "second"
 0002: invoke-static {v2, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: invoke-static {v1, v2}, LNullsKt;.coalesce:(LString;LString;)Ljava/lang/String;
 0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V


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*.class 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000208] NullsKt.coalesce:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 0000: if-eqz v0, 0003
 0002: goto 0004
 0003: move-object v0, v1
 0004: return-object v0
 
 [000224] NullsKt.firstOrSecond:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
 0000: const-string v0, "second"
 0002: invoke-static {v2, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: invoke-static {v1, v2}, LNullsKt;.coalesce:(LString;LString;)Ljava/lang/String;
 0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V


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*.class 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000208] NullsKt.coalesce:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 0000: if-eqz v0, 0003
 0002: goto 0004
 0003: move-object v0, v1
 0004: return-object v0
 
 [000224] NullsKt.firstOrSecond:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
 0000: const-string v0, "second"
 0002: invoke-static {v2, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: invoke-static {v1, v2}, LNullsKt;.coalesce:(LString;LString;)Ljava/lang/String;
 0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V


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*.class 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000208] NullsKt.coalesce:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 0000: if-eqz v0, 0003
 0002: goto 0004
 0003: move-object v0, v1
 0004: return-object v0
 
 [000224] NullsKt.firstOrSecond:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
 0000: const-string v0, "second"
 0002: invoke-static {v2, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: invoke-static {v1, v2}, LNullsKt;.coalesce:(LString;LString;)Ljava/lang/String;
 0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V


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0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void

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0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void

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0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void

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0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void

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0008: move-result-object v1
 0009: if-eqz v1, 000c
 000b: return-object v1
 000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void

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000c: new-instance v1, Ljava/lang/AssertionError;
 000e: invoke-direct {v1}, Ljava/lang/AssertionError;.:()V
 0011: check-cast v1, Ljava/lang/Throwable;
 0013: throw v1
 
 [00025c] NullsKt.main:([Ljava/lang/String;)V
 0000: const-string v0, "args"
 0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void
 
 $ cat rules.txt

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0002: invoke-static {v1, v0}, Lkotlin/jvm/internal/Intrinsics;.checkParameterIsNotNull:(…)V
 0005: const-string v1, "two"
 0007: const/4 v0, #int 0
 0008: invoke-static {v0, v1}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 000b: move-result-object v1
 000c: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000e: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0011: const-string v1, "one"
 0013: const-string v0, "two"
 0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate -allowaccessmodification

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0015: invoke-static {v1, v0}, LNullsKt;.firstOrSecond:(LString;LString;)LString;
 0018: move-result-object v1
 0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate -allowaccessmodification $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar

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0019: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001b: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 001e: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(java.lang.String[]); }Z -dontobfuscate -allowaccessmodification $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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--release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000314] NullsKt.main:([Ljava/lang/String;)V
 0000: if-eqz v1, 0011
 0002: const-string v1, "two"
 0004: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0006: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0009: const-string v1, "one"
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0010: return-void
 0011: const-string v1, "args"
 0013: invoke-static {v1}, Lkotlin/jvm/internal/Intrinsics;.throwParameterIsNullException:(…)V
 0016: const/4 v1, #int 0
 0017: throw v1
 
 [000354] kotlin.jvm.internal.Intrinsics.throwParameterIsNullException:(Ljava/lang/String;)V
 0000: (lots of bytecodes…)

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--release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000314] NullsKt.main:([Ljava/lang/String;)V
 0000: if-eqz v1, 0011
 0002: const-string v1, "two"
 0004: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0006: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0009: const-string v1, "one"
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0010: return-void
 0011: const-string v1, "args"
 0013: invoke-static {v1}, Lkotlin/jvm/internal/Intrinsics;.throwParameterIsNullException:(…)V
 0016: const/4 v1, #int 0
 0017: throw v1
 
 [000354] kotlin.jvm.internal.Intrinsics.throwParameterIsNullException:(Ljava/lang/String;)V
 0000: (lots of bytecodes…)

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--release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000314] NullsKt.main:([Ljava/lang/String;)V
 0000: if-eqz v1, 0011
 0002: const-string v1, "two"
 0004: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0006: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0009: const-string v1, "one"
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0010: return-void
 0011: const-string v1, "args"
 0013: invoke-static {v1}, Lkotlin/jvm/internal/Intrinsics;.throwParameterIsNullException:(…)V
 0016: const/4 v1, #int 0
 0017: throw v1
 
 [000354] kotlin.jvm.internal.Intrinsics.throwParameterIsNullException:(Ljava/lang/String;)V
 0000: (lots of bytecodes…)

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--release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000314] NullsKt.main:([Ljava/lang/String;)V
 0000: if-eqz v1, 0011
 0002: const-string v1, "two"
 0004: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0006: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0009: const-string v1, "one"
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0010: return-void
 0011: const-string v1, "args"
 0013: invoke-static {v1}, Lkotlin/jvm/internal/Intrinsics;.throwParameterIsNullException:(…)V
 0016: const/4 v1, #int 0
 0017: throw v1
 
 [000354] kotlin.jvm.internal.Intrinsics.throwParameterIsNullException:(Ljava/lang/String;)V
 0000: (lots of bytecodes…)

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--release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000314] NullsKt.main:([Ljava/lang/String;)V
 0000: if-eqz v1, 0011
 0002: const-string v1, "two"
 0004: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0006: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0009: const-string v1, "one"
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0010: return-void
 0011: const-string v1, "args"
 0013: invoke-static {v1}, Lkotlin/jvm/internal/Intrinsics;.throwParameterIsNullException:(…)V
 0016: const/4 v1, #int 0
 0017: throw v1
 
 [000354] kotlin.jvm.internal.Intrinsics.throwParameterIsNullException:(Ljava/lang/String;)V
 0000: (lots of bytecodes…)

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--release \
 --output . \
 --pg-conf rules.txt \
 *.class kotlin-stdlib-1.2.61.jar
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000314] NullsKt.main:([Ljava/lang/String;)V
 0000: if-eqz v1, 0011
 0002: const-string v1, "two"
 0004: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0006: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0009: const-string v1, "one"
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(Ljava/lang/Object;)V
 0010: return-void
 0011: const-string v1, "args"
 0013: invoke-static {v1}, Lkotlin/jvm/internal/Intrinsics;.throwParameterIsNullException:(…)V
 0016: const/4 v1, #int 0
 0017: throw v1
 
 [000354] kotlin.jvm.internal.Intrinsics.throwParameterIsNullException:(Ljava/lang/String;)V
 0000: (lots of bytecodes…)

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$ cat SdkIntSimple.java

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$ cat SdkIntSimple.java import android.os.Build; class SdkIntSimple { public static void main(String... args) { if (Build.VERSION.SDK_INT >= 21) { System.out.println("21+"); } else if (Build.VERSION.SDK_INT >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); } } }

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$ cat SdkIntSimple.java import android.os.Build; class SdkIntSimple { public static void main(String... args) { if (Build.VERSION.SDK_INT >= 21) { System.out.println("21+"); } else if (Build.VERSION.SDK_INT >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z $ javac -bootclasspath $ANDROID_HOME/platforms/android-28/android.jar *.java

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class SdkIntSimple { public static void main(String... args) { if (Build.VERSION.SDK_INT >= 21) { System.out.println("21+"); } else if (Build.VERSION.SDK_INT >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z $ javac -bootclasspath $ANDROID_HOME/platforms/android-28/android.jar *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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public static void main(String... args) { if (Build.VERSION.SDK_INT >= 21) { System.out.println("21+"); } else if (Build.VERSION.SDK_INT >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z $ javac -bootclasspath $ANDROID_HOME/platforms/android-28/android.jar *.java $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

Slide 191

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void

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$ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000170] SdkIntSimple.main:([Ljava/lang/String;)V
 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v0, #int 21
 0004: if-lt v1, v0, 000e
 0006: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0008: const-string v0, "21+"
 000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void
 
 $ cat rules.txt

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000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A

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000a: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 000d: goto 0023
 000e: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I
 0010: const/16 v0, #int 16
 0012: if-lt v1, v0, 001c
 0014: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 0016: const-string v0, "16+"
 0018: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A

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001b: goto 0023
 001c: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream;
 001e: const-string v0, "Pre-16"
 0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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0020: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V
 0023: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000130] SdkIntSimple.main:([Ljava/lang/String;)V 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I 0002: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream; 0004: const-string v0, "21+" 0006: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V 0009: return-void

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public static void main(...);
 } 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000130] SdkIntSimple.main:([Ljava/lang/String;)V 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I 0002: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream; 0004: const-string v0, "21+" 0006: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V 0009: return-void

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public static void main(...);
 } 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000130] SdkIntSimple.main:([Ljava/lang/String;)V 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I 0002: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream; 0004: const-string v0, "21+" 0006: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V 0009: return-void

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public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [000130] SdkIntSimple.main:([Ljava/lang/String;)V 0000: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I 0002: sget-object v1, Ljava/lang/System;.out:Ljava/io/PrintStream; 0004: const-string v0, "21+" 0006: invoke-virtual {v1, v0}, Ljava/io/PrintStream;.println:(Ljava/lang/String;)V 0009: return-void

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class SdkIntSimple { public static void main(String... args) { if (Build.VERSION.SDK_INT >= 21) { System.out.println("21+"); } else if (Build.VERSION.SDK_INT >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z

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class SdkIntSimple { public static void main(String... args) { if (Build.VERSION.SDK_INT >= 21) { System.out.println("21+"); } else if (Build.VERSION.SDK_INT >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }

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Build.VERSION.SDK_INT Build.VERSION.SDK_INT class SdkIntSimple { public static void main(String... args) { if ([21..2147483647] >= 21) { System.out.println("21+"); } else if ([21..2147483647] >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class SdkIntSimple { public static void main(String... args) { if ([21..2147483647] >= 21) { System.out.println("21+"); } else if ([21..2147483647] >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class SdkIntSimple { public static void main(String... args) { if (true) { System.out.println("21+"); } else if ([21..2147483647] >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class SdkIntSimple { public static void main(String... args) { if (true) { System.out.println("21+"); } else if ([21..2147483647] >= 16) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class SdkIntSimple { public static void main(String... args) { if (true) { System.out.println("21+"); } else if (true) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class SdkIntSimple { public static void main(String... args) { if (true) { System.out.println("21+"); } else if (true) { System.out.println("16+"); } else { System.out.println("Pre-16"); }X }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class SdkIntSimple { public static void main(String... args) { System.out.println("21+"); }Y }Z -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }G

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class ViewCompat { static void postOnAnimation(@NonNull View view, Runnable action) { if (Build.VERSION.SDK_INT >= 16) { view.postOnAnimation(action); } else { view.postDelayed(action, ValueAnimator.getFrameDelay()); } } static void postInvalidateOnAnimation(@NonNull View view) { if (Build.VERSION.SDK_INT >= 16) { view.postInvalidateOnAnimation(); } else { view.postInvalidate(); } } }Z

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class ViewCompat { static int getPaddingStart(@NonNull View view) { if (Build.VERSION.SDK_INT >= 17) { return view.getPaddingStart(); } return view.getPaddingLeft(); } static int getPaddingEnd(@NonNull View view) { if (Build.VERSION.SDK_INT >= 17) { return view.getPaddingEnd(); } return view.getPaddingRight(); } }Z

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class ViewCompat { public static boolean isInLayout(@NonNull View view) { if (Build.VERSION.SDK_INT >= 18) { return view.isInLayout(); } return false; } public static boolean isLaidOut(@NonNull View view) { if (Build.VERSION.SDK_INT >= 19) { return view.isLaidOut(); } return view.getWidth() > 0 && view.getHeight() > 0; } }Z

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class ViewCompat { static void setElevation(@NonNull View view, float elevation) { if (Build.VERSION.SDK_INT >= 21) { view.setElevation(elevation); } } static float getElevation(@NonNull View view) { if (Build.VERSION.SDK_INT >= 21) { return view.getElevation(); } return 0f; } }Z

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class ViewCompat { static int getMinimumWidth(@NonNull View view) { if (Build.VERSION.SDK_INT >= 16) { return view.getMinimumWidth(); } if (!sMinWidthFieldFetched) { try { sMinWidthField = View.class.getDeclaredField("mMinWidth"); sMinWidthField.setAccessible(true); } catch (NoSuchFieldException e) {} sMinWidthFieldFetched = true; } if (sMinWidthField != null) { try { return (int) sMinWidthField.get(view); } catch (Exception e) {} } return 0; } }Z

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class ViewCompat { static int getMinimumWidth(@NonNull View view) { if (Build.VERSION.SDK_INT >= 16) { return view.getMinimumWidth(); } if (!sMinWidthFieldFetched) { try { sMinWidthField = View.class.getDeclaredField("mMinWidth"); sMinWidthField.setAccessible(true); } catch (NoSuchFieldException e) {} sMinWidthFieldFetched = true; } if (sMinWidthField != null) { try { return (int) sMinWidthField.get(view); } catch (Exception e) {} } return 0; } }Z

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class DrawableCompat { static Drawable wrap(@NonNull Drawable drawable) { if (Build.VERSION.SDK_INT >= 23) { return drawable; } if (Build.VERSION.SDK_INT >= 21) { if (!(drawable instanceof TintAwareDrawable)) { return new WrappedDrawableApi21(drawable); } return drawable; } if (!(drawable instanceof TintAwareDrawable)) { return new WrappedDrawableApi14(drawable); } return drawable; } }Z

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class DrawableCompat { static Drawable wrap(@NonNull Drawable drawable) { if (Build.VERSION.SDK_INT >= 23) { return drawable; } if (Build.VERSION.SDK_INT >= 21) { if (!(drawable instanceof TintAwareDrawable)) { return new WrappedDrawableApi21(drawable); } return drawable; } if (!(drawable instanceof TintAwareDrawable)) { return new WrappedDrawableApi14(drawable); } return drawable; } }Z

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$ grep -r 'SDK_INT' src/main | egrep '( < | <= | > | >= | ==)' | cut -d':' -f1 | cut -d'/' -f4- | sort | uniq -c | sort -r 124 androidx/core/view/accessibility/AccessibilityNodeInfoCompat.java 103 androidx/core/view/ViewCompat.java 65 androidx/core/app/NotificationCompat.java 30 androidx/core/widget/TextViewCompat.java 25 androidx/core/text/PrecomputedTextCompat.java 23 androidx/core/content/ContextCompat.java 23 androidx/core/app/NotificationCompatBuilder.java 20 androidx/core/view/WindowInsetsCompat.java 20 androidx/core/graphics/drawable/DrawableCompat.java 16 androidx/core/view/accessibility/AccessibilityWindowInfoCompat.java 13 androidx/core/view/MenuItemCompat.java 12 androidx/core/app/ActivityCompat.java 11 androidx/core/view/ViewPropertyAnimatorCompat.java 11 androidx/core/os/BuildCompat.java 11 androidx/core/app/ActivityOptionsCompat.java 10 androidx/core/graphics/drawable/IconCompat.java 9 androidx/core/app/RemoteInput.java 8 androidx/core/view/ViewParentCompat.java 8 androidx/core/view/MarginLayoutParamsCompat.java 7 androidx/core/widget/PopupWindowCompat.java 6 androidx/core/widget/ImageViewCompat.java 6 androidx/core/view/accessibility/AccessibilityEventCompat.java 6 androidx/core/view/ViewConfigurationCompat.java 6 androidx/core/view/DisplayCutoutCompat.java 5 androidx/core/widget/CompoundButtonCompat.java 5 androidx/core/view/accessibility/AccessibilityRecordCompat.java 5 androidx/core/view/ViewGroupCompat.java 5 androidx/core/os/HandlerCompat.java 5 androidx/core/content/res/ResourcesCompat.java 5 androidx/core/app/NotificationManagerCompat.java

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$ cat SdkIntElevation.java

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$ cat SdkIntElevation.java import static android.os.Build.VERSION.SDK_INT; import android.view.View; class SdkIntElevation { public static void main(String... args) { View view = new View(null); setElevation(view, 8f); System.out.println(getElevation(view)); }A public static void setElevation(View view, float elevation) { if (SDK_INT >= 21) view.setElevation(elevation); }X public static float getElevation(View view) { return SDK_INT >= 21 ? view.getElevation() : 0f; }Y }Z

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$ cat SdkIntElevation.java import static android.os.Build.VERSION.SDK_INT; import android.view.View; class SdkIntElevation { public static void main(String... args) { View view = new View(null); setElevation(view, 8f); System.out.println(getElevation(view)); }A public static void setElevation(View view, float elevation) { if (SDK_INT >= 21) view.setElevation(elevation); }X public static float getElevation(View view) { return SDK_INT >= 21 ? view.getElevation() : 0f; }Y }Z
 
 $ javac -bootclasspath $ANDROID_HOME/platforms/android-28/android.jar *.java

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View view = new View(null); setElevation(view, 8f); System.out.println(getElevation(view)); }A public static void setElevation(View view, float elevation) { if (SDK_INT >= 21) view.setElevation(elevation); }X public static float getElevation(View view) { return SDK_INT >= 21 ? view.getElevation() : 0f; }Y }Z
 
 $ javac -bootclasspath $ANDROID_HOME/platforms/android-28/android.jar *.java
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class

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System.out.println(getElevation(view)); }A public static void setElevation(View view, float elevation) { if (SDK_INT >= 21) view.setElevation(elevation); }X public static float getElevation(View view) { return SDK_INT >= 21 ? view.getElevation() : 0f; }Y }Z
 
 $ javac -bootclasspath $ANDROID_HOME/platforms/android-28/android.jar *.java
 
 $ java -jar $R8_HOME/build/libs/d8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00020c] SdkIntElevation.main:([Ljava/lang/String;)V
 0000: new-instance v1, Landroid/view/View;
 0002: const/4 v0, #int 0
 0003: invoke-direct {v1, v0}, Landroid/view/View;.:(Landroid/content/Context;)V
 0006: const/high16 v0, #int 1090519040
 0008: invoke-static {v1, v0}, LSdkIntElevation;.setElevation:(Landroid/view/View;F)V
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-static {v1}, LSdkIntElevation;.getElevation:(Landroid/view/View;)F
 0010: move-result v1
 0011: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(F)V
 0014: return-void
 
 [0001c8] SdkIntElevation.getElevation:(Landroid/view/View;)F
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 000b
 0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0


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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00020c] SdkIntElevation.main:([Ljava/lang/String;)V
 0000: new-instance v1, Landroid/view/View;
 0002: const/4 v0, #int 0
 0003: invoke-direct {v1, v0}, Landroid/view/View;.:(Landroid/content/Context;)V
 0006: const/high16 v0, #int 1090519040
 0008: invoke-static {v1, v0}, LSdkIntElevation;.setElevation:(Landroid/view/View;F)V
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-static {v1}, LSdkIntElevation;.getElevation:(Landroid/view/View;)F
 0010: move-result v1
 0011: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(F)V
 0014: return-void
 
 [0001c8] SdkIntElevation.getElevation:(Landroid/view/View;)F
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 000b
 0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0


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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00020c] SdkIntElevation.main:([Ljava/lang/String;)V
 0000: new-instance v1, Landroid/view/View;
 0002: const/4 v0, #int 0
 0003: invoke-direct {v1, v0}, Landroid/view/View;.:(Landroid/content/Context;)V
 0006: const/high16 v0, #int 1090519040
 0008: invoke-static {v1, v0}, LSdkIntElevation;.setElevation:(Landroid/view/View;F)V
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-static {v1}, LSdkIntElevation;.getElevation:(Landroid/view/View;)F
 0010: move-result v1
 0011: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(F)V
 0014: return-void
 
 [0001c8] SdkIntElevation.getElevation:(Landroid/view/View;)F
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 000b
 0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0


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*.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00020c] SdkIntElevation.main:([Ljava/lang/String;)V
 0000: new-instance v1, Landroid/view/View;
 0002: const/4 v0, #int 0
 0003: invoke-direct {v1, v0}, Landroid/view/View;.:(Landroid/content/Context;)V
 0006: const/high16 v0, #int 1090519040
 0008: invoke-static {v1, v0}, LSdkIntElevation;.setElevation:(Landroid/view/View;F)V
 000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-static {v1}, LSdkIntElevation;.getElevation:(Landroid/view/View;)F
 0010: move-result v1
 0011: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(F)V
 0014: return-void
 
 [0001c8] SdkIntElevation.getElevation:(Landroid/view/View;)F
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 000b
 0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0


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000b: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream;
 000d: invoke-static {v1}, LSdkIntElevation;.getElevation:(Landroid/view/View;)F
 0010: move-result v1
 0011: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(F)V
 0014: return-void
 
 [0001c8] SdkIntElevation.getElevation:(Landroid/view/View;)F
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 000b
 0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0
 000c: return v2
 
 [000248] SdkIntElevation.setElevation:(Landroid/view/View;F)V
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 0009
 0006: invoke-virtual {v2, v3}, Landroid/view/View;.setElevation:(F)V
 0009: return-void

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0010: move-result v1
 0011: invoke-virtual {v0, v1}, Ljava/io/PrintStream;.println:(F)V
 0014: return-void
 
 [0001c8] SdkIntElevation.getElevation:(Landroid/view/View;)F
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 000b
 0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0
 000c: return v2
 
 [000248] SdkIntElevation.setElevation:(Landroid/view/View;F)V
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 0009
 0006: invoke-virtual {v2, v3}, Landroid/view/View;.setElevation:(F)V
 0009: return-void
 
 $ cat rules.txt

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0006: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F
 0009: move-result v2
 000a: goto 000c
 000b: const/4 v2, #int 0
 000c: return v2
 
 [000248] SdkIntElevation.setElevation:(Landroid/view/View;F)V
 0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 0009
 0006: invoke-virtual {v2, v3}, Landroid/view/View;.setElevation:(F)V
 0009: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A

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0000: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I
 0002: const/16 v1, #int 21
 0004: if-lt v0, v1, 0009
 0006: invoke-virtual {v2, v3}, Landroid/view/View;.setElevation:(F)V
 0009: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class

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0004: if-lt v0, v1, 0009
 0006: invoke-virtual {v2, v3}, Landroid/view/View;.setElevation:(F)V
 0009: return-void
 
 $ cat rules.txt -keepclasseswithmembers class * { public static void main(...);
 }B 
 -assumevalues class android.os.Build$VERSION { int SDK_INT return 21..2147483647; }A
 
 $ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex

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$ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00017c] SdkIntElevation.main:([Ljava/lang/String;)V 0000: new-instance v2, Landroid/view/View; 0002: const/4 v0, #int 0 0003: invoke-direct {v2, v0}, Landroid/view/View;.:(Landroid/content/Context;)V 0006: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I 0008: const/high16 v0, #int 1090519040 000a: invoke-virtual {v2, v0}, Landroid/view/View;.setElevation:(F)V 000d: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream; 000f: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I 0011: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F 0014: move-result v2 0015: invoke-virtual {v0, v2}, Ljava/io/PrintStream;.println:(F)V 0018: return-void

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$ java -jar $R8_HOME/build/libs/r8.jar \
 --lib $ANDROID_HOME/platforms/android-28/android.jar \
 --release \
 --output . \
 --pg-conf rules.txt \
 *.class
 
 $ $ANDROID_HOME/build-tools/28.0.2/dexdump -d classes.dex [00017c] SdkIntElevation.main:([Ljava/lang/String;)V 0000: new-instance v2, Landroid/view/View; 0002: const/4 v0, #int 0 0003: invoke-direct {v2, v0}, Landroid/view/View;.:(Landroid/content/Context;)V 0006: sget v0, Landroid/os/Build$VERSION;.SDK_INT:I 0008: const/high16 v0, #int 1090519040 000a: invoke-virtual {v2, v0}, Landroid/view/View;.setElevation:(F)V 000d: sget-object v0, Ljava/lang/System;.out:Ljava/io/PrintStream; 000f: sget v1, Landroid/os/Build$VERSION;.SDK_INT:I 0011: invoke-virtual {v2}, Landroid/view/View;.getElevation:()F 0014: move-result v2 0015: invoke-virtual {v0, v2}, Ljava/io/PrintStream;.println:(F)V 0018: return-void

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$ grep -r 'SDK_INT' src/main | egrep '( < | <= | > | >= | ==)' | cut -d':' -f1 | cut -d'/' -f4- | sort | uniq -c | sort -r 124 androidx/core/view/accessibility/AccessibilityNodeInfoCompat.java 103 androidx/core/view/ViewCompat.java 65 androidx/core/app/NotificationCompat.java 30 androidx/core/widget/TextViewCompat.java 25 androidx/core/text/PrecomputedTextCompat.java 23 androidx/core/content/ContextCompat.java 23 androidx/core/app/NotificationCompatBuilder.java 20 androidx/core/view/WindowInsetsCompat.java 20 androidx/core/graphics/drawable/DrawableCompat.java 16 androidx/core/view/accessibility/AccessibilityWindowInfoCompat.java 13 androidx/core/view/MenuItemCompat.java 12 androidx/core/app/ActivityCompat.java 11 androidx/core/view/ViewPropertyAnimatorCompat.java 11 androidx/core/os/BuildCompat.java 11 androidx/core/app/ActivityOptionsCompat.java 10 androidx/core/graphics/drawable/IconCompat.java 9 androidx/core/app/RemoteInput.java 8 androidx/core/view/ViewParentCompat.java 8 androidx/core/view/MarginLayoutParamsCompat.java 7 androidx/core/widget/PopupWindowCompat.java 6 androidx/core/widget/ImageViewCompat.java 6 androidx/core/view/accessibility/AccessibilityEventCompat.java 6 androidx/core/view/ViewConfigurationCompat.java 6 androidx/core/view/DisplayCutoutCompat.java 5 androidx/core/widget/CompoundButtonCompat.java 5 androidx/core/view/accessibility/AccessibilityRecordCompat.java 5 androidx/core/view/ViewGroupCompat.java 5 androidx/core/os/HandlerCompat.java 5 androidx/core/content/res/ResourcesCompat.java 5 androidx/core/app/NotificationManagerCompat.java

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$ cat gradle.properties

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$ cat gradle.properties
 
 # Use R8 instead of ProGuard for code shrinking. android.enableR8=true

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https://jakes.link/java-bytecode

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DIGGING INTO D8 AND R8 @JakeWharton