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| ; RUN: opt < %s -sample-profile -sample-profile-file=%S/Inputs/branch.prof | opt -analyze -branch-prob | FileCheck %s
; RUN: opt < %s -passes=sample-profile -sample-profile-file=%S/Inputs/branch.prof | opt -analyze -branch-prob | FileCheck %s
; Original C++ code for this test case:
;
; #include <stdio.h>
; #include <stdlib.h>
; int main(int argc, char *argv[]) {
; if (argc < 2)
; return 1;
; double result;
; int limit = atoi(argv[1]);
; if (limit > 100) {
; double s = 23.041968 * atoi(argv[2]);
; for (int u = 0; u < limit; u++) {
; double x = s;
; s = x + 3.049 + (double)u;
; s -= s + 3.94 / x * 0.32;
; }
; result = s;
; } else {
; result = atoi(argv[2]);
; }
; printf("result is %lf\n", result);
; return 0;
; }
@.str = private unnamed_addr constant [15 x i8] c"result is %lf\0A\00", align 1
; Function Attrs: uwtable
define i32 @main(i32 %argc, i8** %argv) #0 !dbg !6 {
; CHECK: Printing analysis 'Branch Probability Analysis' for function 'main':
entry:
%retval = alloca i32, align 4
%argc.addr = alloca i32, align 4
%argv.addr = alloca i8**, align 8
%result = alloca double, align 8
%limit = alloca i32, align 4
%s = alloca double, align 8
%u = alloca i32, align 4
%x = alloca double, align 8
store i32 0, i32* %retval, align 4
store i32 %argc, i32* %argc.addr, align 4
call void @llvm.dbg.declare(metadata i32* %argc.addr, metadata !16, metadata !17), !dbg !18
store i8** %argv, i8*** %argv.addr, align 8
call void @llvm.dbg.declare(metadata i8*** %argv.addr, metadata !19, metadata !17), !dbg !20
%0 = load i32, i32* %argc.addr, align 4, !dbg !21
%cmp = icmp slt i32 %0, 2, !dbg !23
br i1 %cmp, label %if.then, label %if.end, !dbg !24
; CHECK: edge entry -> if.then probability is 0x4ccf6b16 / 0x80000000 = 60.01%
; CHECK: edge entry -> if.end probability is 0x333094ea / 0x80000000 = 39.99%
if.then: ; preds = %entry
store i32 1, i32* %retval, align 4, !dbg !25
br label %return, !dbg !25
if.end: ; preds = %entry
call void @llvm.dbg.declare(metadata double* %result, metadata !26, metadata !17), !dbg !27
call void @llvm.dbg.declare(metadata i32* %limit, metadata !28, metadata !17), !dbg !29
%1 = load i8**, i8*** %argv.addr, align 8, !dbg !30
%arrayidx = getelementptr inbounds i8*, i8** %1, i64 1, !dbg !30
%2 = load i8*, i8** %arrayidx, align 8, !dbg !30
%call = call i32 @atoi(i8* %2) #4, !dbg !31
store i32 %call, i32* %limit, align 4, !dbg !29
%3 = load i32, i32* %limit, align 4, !dbg !32
%cmp1 = icmp sgt i32 %3, 100, !dbg !34
br i1 %cmp1, label %if.then.2, label %if.else, !dbg !35
; CHECK: edge if.end -> if.then.2 probability is 0x6652c748 / 0x80000000 = 79.94%
; CHECK: edge if.end -> if.else probability is 0x19ad38b8 / 0x80000000 = 20.06%
if.then.2: ; preds = %if.end
call void @llvm.dbg.declare(metadata double* %s, metadata !36, metadata !17), !dbg !38
%4 = load i8**, i8*** %argv.addr, align 8, !dbg !39
%arrayidx3 = getelementptr inbounds i8*, i8** %4, i64 2, !dbg !39
%5 = load i8*, i8** %arrayidx3, align 8, !dbg !39
%call4 = call i32 @atoi(i8* %5) #4, !dbg !40
%conv = sitofp i32 %call4 to double, !dbg !40
%mul = fmul double 0x40370ABE6A337A81, %conv, !dbg !41
store double %mul, double* %s, align 8, !dbg !38
call void @llvm.dbg.declare(metadata i32* %u, metadata !42, metadata !17), !dbg !44
store i32 0, i32* %u, align 4, !dbg !44
br label %for.cond, !dbg !45
for.cond: ; preds = %for.inc, %if.then.2
%6 = load i32, i32* %u, align 4, !dbg !46
%7 = load i32, i32* %limit, align 4, !dbg !48
%cmp5 = icmp slt i32 %6, %7, !dbg !49
br i1 %cmp5, label %for.body, label %for.end, !dbg !50, !prof !80
; CHECK: edge for.cond -> for.body probability is 0x73333333 / 0x80000000 = 90.00%
; CHECK: edge for.cond -> for.end probability is 0x0ccccccd / 0x80000000 = 10.00%
for.body: ; preds = %for.cond
call void @llvm.dbg.declare(metadata double* %x, metadata !51, metadata !17), !dbg !53
%8 = load double, double* %s, align 8, !dbg !54
store double %8, double* %x, align 8, !dbg !53
%9 = load double, double* %x, align 8, !dbg !55
%add = fadd double %9, 3.049000e+00, !dbg !56
%10 = load i32, i32* %u, align 4, !dbg !57
%conv6 = sitofp i32 %10 to double, !dbg !57
%add7 = fadd double %add, %conv6, !dbg !58
store double %add7, double* %s, align 8, !dbg !59
%11 = load double, double* %s, align 8, !dbg !60
%12 = load double, double* %x, align 8, !dbg !61
%div = fdiv double 3.940000e+00, %12, !dbg !62
%mul8 = fmul double %div, 3.200000e-01, !dbg !63
%add9 = fadd double %11, %mul8, !dbg !64
%13 = load double, double* %s, align 8, !dbg !65
%sub = fsub double %13, %add9, !dbg !65
store double %sub, double* %s, align 8, !dbg !65
br label %for.inc, !dbg !66
for.inc: ; preds = %for.body
%14 = load i32, i32* %u, align 4, !dbg !67
%inc = add nsw i32 %14, 1, !dbg !67
store i32 %inc, i32* %u, align 4, !dbg !67
br label %for.cond, !dbg !68
for.end: ; preds = %for.cond
%15 = load double, double* %s, align 8, !dbg !69
store double %15, double* %result, align 8, !dbg !70
br label %if.end.13, !dbg !71
if.else: ; preds = %if.end
%16 = load i8**, i8*** %argv.addr, align 8, !dbg !72
%arrayidx10 = getelementptr inbounds i8*, i8** %16, i64 2, !dbg !72
%17 = load i8*, i8** %arrayidx10, align 8, !dbg !72
%call11 = call i32 @atoi(i8* %17) #4, !dbg !74
%conv12 = sitofp i32 %call11 to double, !dbg !74
store double %conv12, double* %result, align 8, !dbg !75
br label %if.end.13
if.end.13: ; preds = %if.else, %for.end
%18 = load double, double* %result, align 8, !dbg !76
%call14 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([15 x i8], [15 x i8]* @.str, i32 0, i32 0), double %18), !dbg !77
store i32 0, i32* %retval, align 4, !dbg !78
br label %return, !dbg !78
return: ; preds = %if.end.13, %if.then
%19 = load i32, i32* %retval, align 4, !dbg !79
ret i32 %19, !dbg !79
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
; Function Attrs: nounwind readonly
declare i32 @atoi(i8*) #2
declare i32 @printf(i8*, ...) #3
attributes #0 = { uwtable "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind readonly "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #3 = { "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #4 = { nounwind readonly }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!13, !14}
!llvm.ident = !{!15}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 248211) (llvm/trunk 248217)", isOptimized: false, runtimeVersion: 0, emissionKind: NoDebug, enums: !2, retainedTypes: !3)
!1 = !DIFile(filename: "test.cc", directory: "/ssd/llvm_commit")
!2 = !{}
!3 = !{!4}
!4 = !DIBasicType(name: "double", size: 64, align: 64, encoding: DW_ATE_float)
!6 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 4, type: !7, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: false, unit: !0, retainedNodes: !2)
!7 = !DISubroutineType(types: !8)
!8 = !{!9, !9, !10}
!9 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!10 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !11, size: 64, align: 64)
!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64, align: 64)
!12 = !DIBasicType(name: "char", size: 8, align: 8, encoding: DW_ATE_signed_char)
!13 = !{i32 2, !"Dwarf Version", i32 4}
!14 = !{i32 2, !"Debug Info Version", i32 3}
!15 = !{!"clang version 3.8.0 (trunk 248211) (llvm/trunk 248217)"}
!16 = !DILocalVariable(name: "argc", arg: 1, scope: !6, file: !1, line: 4, type: !9)
!17 = !DIExpression()
!18 = !DILocation(line: 4, column: 15, scope: !6)
!19 = !DILocalVariable(name: "argv", arg: 2, scope: !6, file: !1, line: 4, type: !10)
!20 = !DILocation(line: 4, column: 27, scope: !6)
!21 = !DILocation(line: 5, column: 8, scope: !22)
!22 = distinct !DILexicalBlock(scope: !6, file: !1, line: 5, column: 8)
!23 = !DILocation(line: 5, column: 13, scope: !22)
!24 = !DILocation(line: 5, column: 8, scope: !6)
!25 = !DILocation(line: 6, column: 6, scope: !22)
!26 = !DILocalVariable(name: "result", scope: !6, file: !1, line: 7, type: !4)
!27 = !DILocation(line: 7, column: 11, scope: !6)
!28 = !DILocalVariable(name: "limit", scope: !6, file: !1, line: 8, type: !9)
!29 = !DILocation(line: 8, column: 8, scope: !6)
!30 = !DILocation(line: 8, column: 21, scope: !6)
!31 = !DILocation(line: 8, column: 16, scope: !6)
!32 = !DILocation(line: 9, column: 8, scope: !33)
!33 = distinct !DILexicalBlock(scope: !6, file: !1, line: 9, column: 8)
!34 = !DILocation(line: 9, column: 14, scope: !33)
!35 = !DILocation(line: 9, column: 8, scope: !6)
!36 = !DILocalVariable(name: "s", scope: !37, file: !1, line: 10, type: !4)
!37 = distinct !DILexicalBlock(scope: !33, file: !1, line: 9, column: 21)
!38 = !DILocation(line: 10, column: 13, scope: !37)
!39 = !DILocation(line: 10, column: 34, scope: !37)
!40 = !DILocation(line: 10, column: 29, scope: !37)
!41 = !DILocation(line: 10, column: 27, scope: !37)
!42 = !DILocalVariable(name: "u", scope: !43, file: !1, line: 11, type: !9)
!43 = distinct !DILexicalBlock(scope: !37, file: !1, line: 11, column: 6)
!44 = !DILocation(line: 11, column: 15, scope: !43)
!45 = !DILocation(line: 11, column: 11, scope: !43)
!46 = !DILocation(line: 11, column: 22, scope: !47)
!47 = distinct !DILexicalBlock(scope: !43, file: !1, line: 11, column: 6)
!48 = !DILocation(line: 11, column: 26, scope: !47)
!49 = !DILocation(line: 11, column: 24, scope: !47)
!50 = !DILocation(line: 11, column: 6, scope: !43)
!51 = !DILocalVariable(name: "x", scope: !52, file: !1, line: 12, type: !4)
!52 = distinct !DILexicalBlock(scope: !47, file: !1, line: 11, column: 38)
!53 = !DILocation(line: 12, column: 15, scope: !52)
!54 = !DILocation(line: 12, column: 19, scope: !52)
!55 = !DILocation(line: 13, column: 12, scope: !52)
!56 = !DILocation(line: 13, column: 14, scope: !52)
!57 = !DILocation(line: 13, column: 32, scope: !52)
!58 = !DILocation(line: 13, column: 22, scope: !52)
!59 = !DILocation(line: 13, column: 10, scope: !52)
!60 = !DILocation(line: 14, column: 13, scope: !52)
!61 = !DILocation(line: 14, column: 24, scope: !52)
!62 = !DILocation(line: 14, column: 22, scope: !52)
!63 = !DILocation(line: 14, column: 26, scope: !52)
!64 = !DILocation(line: 14, column: 15, scope: !52)
!65 = !DILocation(line: 14, column: 10, scope: !52)
!66 = !DILocation(line: 15, column: 6, scope: !52)
!67 = !DILocation(line: 11, column: 34, scope: !47)
!68 = !DILocation(line: 11, column: 6, scope: !47)
!69 = !DILocation(line: 16, column: 15, scope: !37)
!70 = !DILocation(line: 16, column: 13, scope: !37)
!71 = !DILocation(line: 17, column: 4, scope: !37)
!72 = !DILocation(line: 18, column: 20, scope: !73)
!73 = distinct !DILexicalBlock(scope: !33, file: !1, line: 17, column: 11)
!74 = !DILocation(line: 18, column: 15, scope: !73)
!75 = !DILocation(line: 18, column: 13, scope: !73)
!76 = !DILocation(line: 20, column: 30, scope: !6)
!77 = !DILocation(line: 20, column: 4, scope: !6)
!78 = !DILocation(line: 21, column: 4, scope: !6)
!79 = !DILocation(line: 22, column: 2, scope: !6)
!80 = !{!"branch_weights", i32 90, i32 10}
|