UP Lecture 26

Compilers
Intermediate Code III
(202605)

Transcript

1. jgs jgs Compilers Lecture 26: Intermediate Code III Dr. Javier Gonzalez-Sanchez jgonzalezs@up.edu.mx
2. jgs jgs Previously …
3. Dr. Javier Gonzalez-Sanchez | Compilers | 3 jgs jgs Translate Source to Object { int a; int b; int c; int d; if (a != 5) { b = c + d; } print (a); } a,int,global 0 b,int,global 0 c,int,global 0 d,int,global 0 #E1,int,label,9 #P,int,label,1 @ lod , 0 lit 5, 0 opr 14, 0 jmc #e1, false lod c, 0 lod d, 0 opr 2, 0 sto b, 0 lod a, 0 opr 21, 0 opr 1, 0
4. jgs jgs Next
5. Dr. Javier Gonzalez-Sanchez | Compilers | 5 jgs jgs Programming Assignment 4 Level 1 LIT, LOD, STO, OPR
6. Dr. Javier Gonzalez-Sanchez | Compilers | 6 jgs jgs Code PROGRAM OPR 0, 0
7. Dr. Javier Gonzalez-Sanchez | Compilers | 7 jgs jgs Your Code Should be
8. Dr. Javier Gonzalez-Sanchez | Compilers | 8 jgs jgs Code BODY
9. Dr. Javier Gonzalez-Sanchez | Compilers | 9 jgs jgs Code PRINT OPR 21, 0
10. Dr. Javier Gonzalez-Sanchez | Compilers | 10 jgs jgs Code ASSIGNMENT STO identifier, 0
11. Dr. Javier Gonzalez-Sanchez | Compilers | 11 jgs jgs Code VARIABLE identifier, <type>
12. Dr. Javier Gonzalez-Sanchez | Compilers | 12 jgs jgs Code RETURN OPR 1, 0
13. Dr. Javier Gonzalez-Sanchez | Compilers | 13 jgs jgs Code EXPRESSION if (twice) { OPR 8, 0 }
14. Dr. Javier Gonzalez-Sanchez | Compilers | 14 jgs jgs Your Code Should be
15. Dr. Javier Gonzalez-Sanchez | Compilers | 15 jgs jgs Code X if (twice) { OPR 9, 0 }
16. Dr. Javier Gonzalez-Sanchez | Compilers | 16 jgs jgs Code Y if (operatorUsed) { OPR 10, 0 }
17. Dr. Javier Gonzalez-Sanchez | Compilers | 17 jgs jgs Code R if (twice) { OPR <operatorNumber>, 0 }
18. Dr. Javier Gonzalez-Sanchez | Compilers | 18 jgs jgs Code E if (twice) { OPR <operatorNumber>, 0 }
19. Dr. Javier Gonzalez-Sanchez | Compilers | 19 jgs jgs Parser A if (twice) { OPR <operatorNumber>, 0 }
20. Dr. Javier Gonzalez-Sanchez | Compilers | 20 jgs jgs Code B if (operatorUsed) { OPR 3, 0 } LIT 0, 0
21. Dr. Javier Gonzalez-Sanchez | Compilers | 21 jgs jgs Code C LIT <value>, 0 LOD identifier, 0
22. Dr. Javier Gonzalez-Sanchez | Compilers | 22 jgs jgs Review Programming Assignment 4 Level 2 JMP, JMC
23. Dr. Javier Gonzalez-Sanchez | Compilers | 23 jgs jgs Instructions ▪ JMP <line>, 0 Put the value <line> in the program counter; thus, the next line to be executed will be <line> Examples: JMP 1, 0 JMP 14, 0 JMP 75, 0
24. Dr. Javier Gonzalez-Sanchez | Compilers | 24 jgs jgs Instructions ▪ JMC <line>, <condition> Read one value from the CPU register If the value is equal to <condition>, put the value <line> in the program counter; thus, the next line to be executed will be <line> Examples: JMC 1, true JMC 14, false JMC 75, true
25. Dr. Javier Gonzalez-Sanchez | Compilers | 25 jgs jgs Example | if { int a; int b; a = 10; if (a>1) { print (a); } else { print (b); } return; } int a global 0 int b global 0 int #e1 global 10 int #e2 global 12 LIT 10, 0 STO a, 0 LOD a, 0 LIT 1, 0 OPR 11, 0 ; > JMC #e1, false LOD a, 0 OPR 20, 0 ;print JMP #e2, 0 LOD b, 0 OPR 20, 0 ;print OPR 1, 0 OPR 0, 0
26. jgs jgs To be continued …
27. Dr. Javier Gonzalez-Sanchez | Compilers | 27 jgs jgs Homework Assignment #4
28. Dr. Javier Gonzalez-Sanchez | Compilers | 28 jgs jgs Questions
29. jgs jgs Compilers Javier Gonzalez-Sanchez, Ph.D. jgonzalezs@up.edu.mx Spring 2025 Copyright. These slides can only be used as study material for the Compilers course at Universidad Panamericana. They cannot be distributed or used for another purpose.