Swift build time optimization

Brief sample of some code optimization for the compiler

Transcript

1. SWIFT build time optimizations
2. @CoderPug
3. Clean code vs Compiler friendly code
4. Surprise!
5. Individual routines
6. Nil coalescing
7. // Build time: 5238.3ms return CGSize(width: size.width + (rightView?.bounds.width ?? 0) + (leftView?.bounds.width ?? 0) + 22, height: bounds.height) // Build time: 32.4ms var padding: CGFloat = 22 if let rightView = rightView { padding += rightView.bounds.width } if let leftView = leftView { padding += leftView.bounds.width } return CGSizeMake(size.width + padding, bounds.height)
8. Array + [stuff]
9. // Build time: 1250.3ms let systemOptions = [ 7, 14, 30, -1 ] let systemNames = (0...2).map{ String(format: localizedFormat, systemOptions[$0]) } + [NSLocalizedString("everything", comment: "")] // Some code in-between labelNames = Array(systemNames[0..<count]) + [systemNames.last!] // Build time: 25.5ms let systemOptions = [ 7, 14, 30, -1 ] var systemNames = systemOptions.dropLast().map{ String(format: localizedFormat, $0) } systemNames.append(NSLocalizedString("everything", comment: "")) // Some code in-between labelNames = Array(systemNames[0..<count]) labelNames.append(systemNames.last!)
10. Ternary operator
11. // Build time: 239.0ms let labelNames = type == 0 ? (1...5).map{type0ToString($0)} : (0...2).map{type1ToString($0)} // Build time: 16.9ms var labelNames: [String] if type == 0 { labelNames = (1...5).map{type0ToString($0)} } else { labelNames = (0...2).map{type1ToString($0)} }
12. Casting CGFloat
13. // Build time: 3431.7ms return CGFloat(M_PI) * (CGFloat((hour + hourDelta + CGFloat(minute + minuteDelta) / 60) * 5) - 15) * unit / 180 // Build time: 3.0ms return CGFloat(M_PI) * ((hour + hourDelta + (minute + minuteDelta) / 60) * 5 - 15) * unit / 180
14. Round()
15. // Build time: 1433.7ms let expansion = a - b - c + round(d * 0.66) + e // Build time: 34.7ms let expansion = a - b - c + d * 0.66 + e
16. Closures and lazy properties
17. // 1905.5ms private(set) lazy var chartViewColors: [UIColor] = [ self.chartColor, UIColor(red: 86/255, green: 84/255, blue: 124/255, alpha: 1), UIColor(red: 80/255, green: 88/255, blue: 92/255, alpha: 1), UIColor(red: 126/255, green: 191/255, blue: 189/255, alpha: 1), UIColor(red: 161/255, green: 77/255, blue: 63/255, alpha: 1), UIColor(red: 235/255, green: 185/255, blue: 120/255, alpha: 1), UIColor(red: 100/255, green: 126/255, blue: 159/255, alpha: 1), UIColor(red: 160/255, green: 209/255, blue: 109/255, alpha: 1), self.backgroundGradientView.upperColor ]
18. // 2565.3ms private let createChartViewColors = { () -> [UIColor] in let colors = [ UIColor(red: 86/255, green: 84/255, blue: 124/255, alpha: 1), UIColor(red: 80/255, green: 88/255, blue: 92/255, alpha: 1), UIColor(red: 126/255, green: 191/255, blue: 189/255, alpha: 1), UIColor(red: 161/255, green: 77/255, blue: 63/255, alpha: 1), UIColor(red: 235/255, green: 185/255, blue: 120/255, alpha: 1), UIColor(red: 100/255, green: 126/255, blue: 159/255, alpha: 1), UIColor(red: 160/255, green: 209/255, blue: 109/255, alpha: 1), ] return colors }
19. // Cumulative build time: 56.3ms private(set) lazy var chartViewColors: [UIColor] = self.createChartViewColors() // Build time: 6.2ms private func createChartViewColors() -> [UIColor] { return [ chartColor, UIColor(red: 86/255, green: 84/255, blue: 124/25 UIColor(red: 80/255, green: 88/255, blue: 92/255 UIColor(red: 126/255, green: 191/255, blue: 189/ UIColor(red: 161/255, green: 77/255, blue: 63/25 UIColor(red: 235/255, green: 185/255, blue: 120/ UIColor(red: 100/255, green: 126/255, blue: 159/ UIColor(red: 160/255, green: 209/255, blue: 109/ backgroundGradientView.upperColor ] }
20. Build time analyzer
22. References https://github.com/RobertGummesson/BuildTimeAnalyzer- for-Xcode
23. THANKS!