1 ; RUN: opt < %s -instcombine -sample-profile -sample-profile-file=%S/Inputs/calls.prof | opt -analyze -branch-prob | FileCheck %s 2 ; RUN: opt < %s -passes="function(instcombine),sample-profile" -sample-profile-file=%S/Inputs/calls.prof | opt -analyze -branch-prob | FileCheck %s 3 4 ; Original C++ test case 5 ; 6 ; #include <stdio.h> 7 ; 8 ; int sum(int x, int y) { 9 ; return x + y; 10 ; } 11 ; 12 ; int main() { 13 ; int s, i = 0; 14 ; while (i++ < 20000 * 20000) 15 ; if (i != 100) s = sum(i, s); else s = 30; 16 ; printf("sum is %d\n", s); 17 ; return 0; 18 ; } 19 ; 20 @.str = private unnamed_addr constant [11 x i8] c"sum is %d\0A\00", align 1 21 22 ; Function Attrs: nounwind uwtable 23 define i32 @_Z3sumii(i32 %x, i32 %y) !dbg !4 { 24 entry: 25 %x.addr = alloca i32, align 4 26 %y.addr = alloca i32, align 4 27 store i32 %x, i32* %x.addr, align 4 28 store i32 %y, i32* %y.addr, align 4 29 %0 = load i32, i32* %x.addr, align 4, !dbg !11 30 %1 = load i32, i32* %y.addr, align 4, !dbg !11 31 %add = add nsw i32 %0, %1, !dbg !11 32 ret i32 %add, !dbg !11 33 } 34 35 ; Function Attrs: uwtable 36 define i32 @main() !dbg !7 { 37 entry: 38 %retval = alloca i32, align 4 39 %s = alloca i32, align 4 40 %i = alloca i32, align 4 41 store i32 0, i32* %retval 42 store i32 0, i32* %i, align 4, !dbg !12 43 br label %while.cond, !dbg !13 44 45 while.cond: ; preds = %if.end, %entry 46 %0 = load i32, i32* %i, align 4, !dbg !14 47 %inc = add nsw i32 %0, 1, !dbg !14 48 store i32 %inc, i32* %i, align 4, !dbg !14 49 %cmp = icmp slt i32 %0, 400000000, !dbg !14 50 br i1 %cmp, label %while.body, label %while.end, !dbg !14 51 ; CHECK: edge while.cond -> while.body probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 52 ; CHECK: edge while.cond -> while.end probability is 0x00000000 / 0x80000000 = 0.00% 53 54 while.body: ; preds = %while.cond 55 %1 = load i32, i32* %i, align 4, !dbg !16 56 %cmp1 = icmp ne i32 %1, 100, !dbg !16 57 br i1 %cmp1, label %if.then, label %if.else, !dbg !16 58 ; Without discriminator information, the profiler used to think that 59 ; both branches out of while.body had the same weight. In reality, 60 ; the edge while.body->if.then is taken most of the time. 61 ; 62 ; CHECK: edge while.body -> if.else probability is 0x00000000 / 0x80000000 = 0.00% 63 ; CHECK: edge while.body -> if.then probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 64 65 66 if.then: ; preds = %while.body 67 %2 = load i32, i32* %i, align 4, !dbg !18 68 %3 = load i32, i32* %s, align 4, !dbg !18 69 %call = call i32 @_Z3sumii(i32 %2, i32 %3), !dbg !18 70 store i32 %call, i32* %s, align 4, !dbg !18 71 br label %if.end, !dbg !18 72 73 if.else: ; preds = %while.body 74 store i32 30, i32* %s, align 4, !dbg !20 75 br label %if.end 76 77 if.end: ; preds = %if.else, %if.then 78 br label %while.cond, !dbg !22 79 80 while.end: ; preds = %while.cond 81 %4 = load i32, i32* %s, align 4, !dbg !24 82 %call2 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([11 x i8], [11 x i8]* @.str, i32 0, i32 0), i32 %4), !dbg !24 83 ret i32 0, !dbg !25 84 } 85 86 declare i32 @printf(i8*, ...) #2 87 88 !llvm.dbg.cu = !{!0} 89 !llvm.module.flags = !{!8, !9} 90 !llvm.ident = !{!10} 91 92 !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.5 ", isOptimized: false, emissionKind: NoDebug, file: !1, enums: !2, retainedTypes: !2, globals: !2, imports: !2) 93 !1 = !DIFile(filename: "calls.cc", directory: ".") 94 !2 = !{} 95 !4 = distinct !DISubprogram(name: "sum", line: 3, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 3, file: !1, scope: !5, type: !6, variables: !2) 96 !5 = !DIFile(filename: "calls.cc", directory: ".") 97 !6 = !DISubroutineType(types: !2) 98 !7 = distinct !DISubprogram(name: "main", line: 7, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 7, file: !1, scope: !5, type: !6, variables: !2) 99 !8 = !{i32 2, !"Dwarf Version", i32 4} 100 !9 = !{i32 1, !"Debug Info Version", i32 3} 101 !10 = !{!"clang version 3.5 "} 102 !11 = !DILocation(line: 4, scope: !4) 103 !12 = !DILocation(line: 8, scope: !7) 104 !13 = !DILocation(line: 9, scope: !7) 105 !14 = !DILocation(line: 9, scope: !15) 106 !15 = !DILexicalBlockFile(discriminator: 1, file: !1, scope: !7) 107 !16 = !DILocation(line: 10, scope: !17) 108 !17 = distinct !DILexicalBlock(line: 10, column: 0, file: !1, scope: !7) 109 !18 = !DILocation(line: 10, scope: !19) 110 !19 = !DILexicalBlockFile(discriminator: 1, file: !1, scope: !17) 111 !20 = !DILocation(line: 10, scope: !21) 112 !21 = !DILexicalBlockFile(discriminator: 2, file: !1, scope: !17) 113 !22 = !DILocation(line: 10, scope: !23) 114 !23 = !DILexicalBlockFile(discriminator: 3, file: !1, scope: !17) 115 !24 = !DILocation(line: 11, scope: !7) 116 !25 = !DILocation(line: 12, scope: !7) 117
