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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;
; }
;
; Note that this test is missing the llvm.dbg.cu annotation. This emulates
; the effect of the user having only used -fprofile-sample-use without
; -gmlt when invoking the driver. In those cases, we need to track source
; location information but we do not have to generate debug info in the
; final binary.
@.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.module.flags = !{!8, !9}
!llvm.ident = !{!10}
!0 = metadata !{metadata !"0x11\004\00clang version 3.5 \000\00\000\00\000", metadata !1, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2} ; [ 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 !{metadata !"0x2e\00sum\00sum\00\003\000\001\000\006\00256\000\003", metadata !1, metadata !5, metadata !6, null, i32 (i32, i32)* @_Z3sumii, null, null, metadata !2} ; [ DW_TAG_subprogram ] [line 3] [def] [sum]
!5 = metadata !{metadata !"0x29", metadata !1} ; [ DW_TAG_file_type ] [./calls.cc]
!6 = metadata !{metadata !"0x15\00\000\000\000\000\000\000", i32 0, null, null, metadata !2, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!7 = metadata !{metadata !"0x2e\00main\00main\00\007\000\001\000\006\00256\000\007", metadata !1, metadata !5, metadata !6, null, i32 ()* @main, null, null, metadata !2} ; [ 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 2}
!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}
!13 = metadata !{i32 9, i32 0, metadata !7, null}
!14 = metadata !{i32 9, i32 0, metadata !15, null}
!15 = metadata !{metadata !"0xb\001", metadata !1, metadata !7} ; [ DW_TAG_lexical_block ] [./calls.cc]
!16 = metadata !{i32 10, i32 0, metadata !17, null}
!17 = metadata !{metadata !"0xb\0010\000\000", metadata !1, metadata !7} ; [ DW_TAG_lexical_block ] [./calls.cc]
!18 = metadata !{i32 10, i32 0, metadata !19, null}
!19 = metadata !{metadata !"0xb\001", metadata !1, metadata !17} ; [ DW_TAG_lexical_block ] [./calls.cc]
!20 = metadata !{i32 10, i32 0, metadata !21, null}
!21 = metadata !{metadata !"0xb\002", metadata !1, metadata !17} ; [ DW_TAG_lexical_block ] [./calls.cc]
!22 = metadata !{i32 10, i32 0, metadata !23, null}
!23 = metadata !{metadata !"0xb\003", metadata !1, metadata !17} ; [ DW_TAG_lexical_block ] [./calls.cc]
!24 = metadata !{i32 11, i32 0, metadata !7, null}
!25 = metadata !{i32 12, i32 0, metadata !7, null}
|
