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| ; RUN: opt < %s -analyze -branch-prob | FileCheck %s
; RUN: opt < %s -passes='print<branch-prob>' -disable-output 2>&1 | FileCheck %s
; In this test, the else clause is taken about 90% of the time. This was not
; reflected in the probability computation because the weight is larger than
; the branch weight cap (about 2 billion).
;
; CHECK: edge for.body -> if.then probability is 0x0cccba45 / 0x80000000 = 10.00%
; CHECK: edge for.body -> if.else probability is 0x733345bb / 0x80000000 = 90.00% [HOT edge]
@y = common global i64 0, align 8
@x = common global i64 0, align 8
@.str = private unnamed_addr constant [17 x i8] c"x = %lu\0Ay = %lu\0A\00", align 1
; Function Attrs: inlinehint nounwind uwtable
define i32 @main() #0 {
entry:
%retval = alloca i32, align 4
%i = alloca i64, align 8
store i32 0, i32* %retval
store i64 0, i64* @y, align 8
store i64 0, i64* @x, align 8
call void @srand(i32 422304) #3
store i64 0, i64* %i, align 8
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%0 = load i64, i64* %i, align 8
%cmp = icmp ult i64 %0, 13000000000
br i1 %cmp, label %for.body, label %for.end, !prof !1
for.body: ; preds = %for.cond
%call = call i32 @rand() #3
%conv = sitofp i32 %call to double
%mul = fmul double %conv, 1.000000e+02
%div = fdiv double %mul, 0x41E0000000000000
%cmp1 = fcmp ogt double %div, 9.000000e+01
br i1 %cmp1, label %if.then, label %if.else, !prof !2
if.then: ; preds = %for.body
%1 = load i64, i64* @x, align 8
%inc = add i64 %1, 1
store i64 %inc, i64* @x, align 8
br label %if.end
if.else: ; preds = %for.body
%2 = load i64, i64* @y, align 8
%inc3 = add i64 %2, 1
store i64 %inc3, i64* @y, align 8
br label %if.end
if.end: ; preds = %if.else, %if.then
br label %for.inc
for.inc: ; preds = %if.end
%3 = load i64, i64* %i, align 8
%inc4 = add i64 %3, 1
store i64 %inc4, i64* %i, align 8
br label %for.cond
for.end: ; preds = %for.cond
%4 = load i64, i64* @x, align 8
%5 = load i64, i64* @y, align 8
%call5 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([17 x i8], [17 x i8]* @.str, i32 0, i32 0), i64 %4, i64 %5)
ret i32 0
}
; Function Attrs: nounwind
declare void @srand(i32) #1
; Function Attrs: nounwind
declare i32 @rand() #1
declare i32 @printf(i8*, ...) #2
attributes #0 = { inlinehint nounwind uwtable "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 "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 #2 = { "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 = { nounwind }
!llvm.ident = !{!0}
!0 = !{!"clang version 3.7.0 (trunk 236218) (llvm/trunk 236235)"}
!1 = !{!"branch_weights", i32 -1044967295, i32 1}
!2 = !{!"branch_weights", i32 433323762, i32 -394957723}
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