; RUN: opt < %s -passes="function(instcombine),sample-profile" -sample-profile-file=%S/Inputs/calls.prof | opt -passes='print<branch-prob>' -disable-output 2>&1 | FileCheck %s ; Original C++ test case ; ; #include <stdio.h> ; ; int sum(int x, int y) { ; return x + y; ; } ; ; int main() { ; int s, i = 0; ; while (i++ < 20000 * 20000) ; if (i != 100) s = sum(i, s); else s = 30; ; printf("sum is %d\n", s); ; return 0; ; } ; @.str = private unnamed_addr constant [11 x i8] c"sum is %d\0A\00", align 1 ; Function Attrs: nounwind uwtable define i32 @_Z3sumii(i32 %x, i32 %y) #0 !dbg !4 { entry: %x.addr = alloca i32, align 4 %y.addr = alloca i32, align 4 store i32 %x, ptr %x.addr, align 4 store i32 %y, ptr %y.addr, align 4 %0 = load i32, ptr %x.addr, align 4, !dbg !11 %1 = load i32, ptr %y.addr, align 4, !dbg !11 %add = add nsw i32 %0, %1, !dbg !11 ret i32 %add, !dbg !11 } ; Function Attrs: uwtable define i32 @main() #0 !dbg !7 { entry: %retval = alloca i32, align 4 %s = alloca i32, align 4 %i = alloca i32, align 4 store i32 0, ptr %retval store i32 0, ptr %i, align 4, !dbg !12 br label %while.cond, !dbg !13 while.cond: ; preds = %if.end, %entry %0 = load i32, ptr %i, align 4, !dbg !14 %inc = add nsw i32 %0, 1, !dbg !14 store i32 %inc, ptr %i, align 4, !dbg !14 %cmp = icmp slt i32 %0, 400000000, !dbg !14 br i1 %cmp, label %while.body, label %while.end, !dbg !14 ; CHECK: edge while.cond -> while.body probability is 0x77f2798d / 0x80000000 = 93.71% [HOT edge] ; CHECK: edge while.cond -> while.end probability is 0x080d8673 / 0x80000000 = 6.29% while.body: ; preds = %while.cond %1 = load i32, ptr %i, align 4, !dbg !16 %cmp1 = icmp ne i32 %1, 100, !dbg !16 br i1 %cmp1, label %if.then, label %if.else, !dbg !16 ; Without discriminator information, the profiler used to think that ; both branches out of while.body had the same weight. In reality, ; the edge while.body->if.then is taken most of the time. ; ; CHECK: edge while.body -> if.else probability is 0x0005b1e0 / 0x80000000 = 0.02% ; CHECK: edge while.body -> if.then probability is 0x7ffa4e20 / 0x80000000 = 99.98% [HOT edge] if.then: ; preds = %while.body %2 = load i32, ptr %i, align 4, !dbg !18 %3 = load i32, ptr %s, align 4, !dbg !18 %call = call i32 @_Z3sumii(i32 %2, i32 %3), !dbg !18 store i32 %call, ptr %s, align 4, !dbg !18 br label %if.end, !dbg !18 if.else: ; preds = %while.body store i32 30, ptr %s, align 4, !dbg !20 br label %if.end if.end: ; preds = %if.else, %if.then br label %while.cond, !dbg !22 while.end: ; preds = %while.cond %4 = load i32, ptr %s, align 4, !dbg !24 %call2 = call i32 (ptr, ...) @printf(ptr @.str, i32 %4), !dbg !24 ret i32 0, !dbg !25 } declare i32 @printf(ptr, ...) #2 attributes #0 = {"use-sample-profile"} !llvm.dbg.cu = !{!0} !llvm.module.flags = !{!8, !9} !llvm.ident = !{!10} !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) !1 = !DIFile(filename: "calls.cc", directory: ".") !2 = !{} !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, retainedNodes: !2) !5 = !DIFile(filename: "calls.cc", directory: ".") !6 = !DISubroutineType(types: !2) !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, retainedNodes: !2) !8 = !{i32 2, !"Dwarf Version", i32 4} !9 = !{i32 1, !"Debug Info Version", i32 3} !10 = !{!"clang version 3.5 "} !11 = !DILocation(line: 4, scope: !4) !12 = !DILocation(line: 8, scope: !7) !13 = !DILocation(line: 9, scope: !7) !14 = !DILocation(line: 9, scope: !15) !15 = !DILexicalBlockFile(discriminator: 2, file: !1, scope: !7) !16 = !DILocation(line: 10, scope: !17) !17 = distinct !DILexicalBlock(line: 10, column: 0, file: !1, scope: !7) !18 = !DILocation(line: 10, scope: !19) !19 = !DILexicalBlockFile(discriminator: 2, file: !1, scope: !17) !20 = !DILocation(line: 10, scope: !21) !21 = !DILexicalBlockFile(discriminator: 4, file: !1, scope: !17) !22 = !DILocation(line: 10, scope: !23) !23 = !DILexicalBlockFile(discriminator: 6, file: !1, scope: !17) !24 = !DILocation(line: 11, scope: !7) !25 = !DILocation(line: 12, scope: !7)