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; RUN: opt < %s -sample-profile -sample-profile-file=%S/Inputs/calls.prof | opt -analyze -branch-prob | 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) {
entry:
%x.addr = alloca i32, align 4
%y.addr = alloca i32, align 4
store i32 %x, i32* %x.addr, align 4
store i32 %y, i32* %y.addr, align 4
%0 = load i32* %x.addr, align 4, !dbg !11
%1 = load i32* %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() {
entry:
%retval = alloca i32, align 4
%s = alloca i32, align 4
%i = alloca i32, align 4
store i32 0, i32* %retval
store i32 0, i32* %i, align 4, !dbg !12
br label %while.cond, !dbg !13
while.cond: ; preds = %if.end, %entry
%0 = load i32* %i, align 4, !dbg !14
%inc = add nsw i32 %0, 1, !dbg !14
store i32 %inc, i32* %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 5391 / 5392 = 99.9815% [HOT edge]
; CHECK: edge while.cond -> while.end probability is 1 / 5392 = 0.018546%
while.body: ; preds = %while.cond
%1 = load i32* %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.then probability is 5752 / 5753 = 99.9826% [HOT edge]
; CHECK: edge while.body -> if.else probability is 1 / 5753 = 0.0173822%
if.then: ; preds = %while.body
%2 = load i32* %i, align 4, !dbg !18
%3 = load i32* %s, align 4, !dbg !18
%call = call i32 @_Z3sumii(i32 %2, i32 %3), !dbg !18
store i32 %call, i32* %s, align 4, !dbg !18
br label %if.end, !dbg !18
if.else: ; preds = %while.body
store i32 30, i32* %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* %s, align 4, !dbg !24
%call2 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([11 x i8]* @.str, i32 0, i32 0), i32 %4), !dbg !24
ret i32 0, !dbg !25
}
declare i32 @printf(i8*, ...) #2
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!8, !9}
!llvm.ident = !{!10}
!0 = metadata !{i32 786449, metadata !1, i32 4, metadata !"clang version 3.5 ", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2, metadata !""} ; [ DW_TAG_compile_unit ] [./calls.cc] [DW_LANG_C_plus_plus]
!1 = metadata !{metadata !"calls.cc", metadata !"."}
!2 = metadata !{}
!3 = metadata !{metadata !4, metadata !7}
!4 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"sum", metadata !"sum", metadata !"", i32 3, metadata !6, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 (i32, i32)* @_Z3sumii, null, null, metadata !2, i32 3} ; [ DW_TAG_subprogram ] [line 3] [def] [sum]
!5 = metadata !{i32 786473, metadata !1} ; [ DW_TAG_file_type ] [./calls.cc]
!6 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !2, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!7 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"main", metadata !"main", metadata !"", i32 7, metadata !6, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 ()* @main, null, null, metadata !2, i32 7} ; [ DW_TAG_subprogram ] [line 7] [def] [main]
!8 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
!9 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
!10 = metadata !{metadata !"clang version 3.5 "}
!11 = metadata !{i32 4, i32 0, metadata !4, null}
!12 = metadata !{i32 8, i32 0, metadata !7, null} ; [ DW_TAG_imported_declaration ]
!13 = metadata !{i32 9, i32 0, metadata !7, null}
!14 = metadata !{i32 9, i32 0, metadata !15, null}
!15 = metadata !{i32 786443, metadata !1, metadata !7, i32 9, i32 0, i32 1, i32 1} ; [ DW_TAG_lexical_block ] [./calls.cc]
!16 = metadata !{i32 10, i32 0, metadata !17, null}
!17 = metadata !{i32 786443, metadata !1, metadata !7, i32 10, i32 0, i32 0, i32 0} ; [ DW_TAG_lexical_block ] [./calls.cc]
!18 = metadata !{i32 10, i32 0, metadata !19, null}
!19 = metadata !{i32 786443, metadata !1, metadata !17, i32 10, i32 0, i32 1, i32 2} ; [ DW_TAG_lexical_block ] [./calls.cc]
!20 = metadata !{i32 10, i32 0, metadata !21, null}
!21 = metadata !{i32 786443, metadata !1, metadata !17, i32 10, i32 0, i32 2, i32 3} ; [ DW_TAG_lexical_block ] [./calls.cc]
!22 = metadata !{i32 10, i32 0, metadata !23, null}
!23 = metadata !{i32 786443, metadata !1, metadata !17, i32 10, i32 0, i32 3, i32 4} ; [ DW_TAG_lexical_block ] [./calls.cc]
!24 = metadata !{i32 11, i32 0, metadata !7, null}
!25 = metadata !{i32 12, i32 0, metadata !7, null}
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