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; RUN: opt -simplifycfg -S < %s | FileCheck %s
define void @ifconvertstore(i32 %m, i32* %A, i32* %B, i32 %C, i32 %D) {
entry:
%arrayidx = getelementptr inbounds i32* %B, i64 0
%0 = load i32* %arrayidx, align 4
%add = add nsw i32 %0, %C
%arrayidx2 = getelementptr inbounds i32* %A, i64 0
; First store to the location.
store i32 %add, i32* %arrayidx2, align 4
%arrayidx4 = getelementptr inbounds i32* %B, i64 1
%1 = load i32* %arrayidx4, align 4
%add5 = add nsw i32 %1, %D
%cmp6 = icmp sgt i32 %add5, %C
br i1 %cmp6, label %if.then, label %ret.end
; Make sure we speculate stores like the following one. It is cheap compared to
; a mispredicated branch.
; CHECK-LABEL: @ifconvertstore(
; CHECK: %add5.add = select i1 %cmp6, i32 %add5, i32 %add
; CHECK: store i32 %add5.add, i32* %arrayidx2, align 4
if.then:
store i32 %add5, i32* %arrayidx2, align 4
br label %ret.end
ret.end:
ret void
}
define void @noifconvertstore1(i32 %m, i32* %A, i32* %B, i32 %C, i32 %D) {
entry:
%arrayidx = getelementptr inbounds i32* %B, i64 0
%0 = load i32* %arrayidx, align 4
%add = add nsw i32 %0, %C
%arrayidx2 = getelementptr inbounds i32* %A, i64 0
; Store to a different location.
store i32 %add, i32* %arrayidx, align 4
%arrayidx4 = getelementptr inbounds i32* %B, i64 1
%1 = load i32* %arrayidx4, align 4
%add5 = add nsw i32 %1, %D
%cmp6 = icmp sgt i32 %add5, %C
br i1 %cmp6, label %if.then, label %ret.end
; CHECK-LABEL: @noifconvertstore1(
; CHECK-NOT: select
if.then:
store i32 %add5, i32* %arrayidx2, align 4
br label %ret.end
ret.end:
ret void
}
declare void @unknown_fun()
define void @noifconvertstore2(i32 %m, i32* %A, i32* %B, i32 %C, i32 %D) {
entry:
%arrayidx = getelementptr inbounds i32* %B, i64 0
%0 = load i32* %arrayidx, align 4
%add = add nsw i32 %0, %C
%arrayidx2 = getelementptr inbounds i32* %A, i64 0
; First store to the location.
store i32 %add, i32* %arrayidx2, align 4
call void @unknown_fun()
%arrayidx4 = getelementptr inbounds i32* %B, i64 1
%1 = load i32* %arrayidx4, align 4
%add5 = add nsw i32 %1, %D
%cmp6 = icmp sgt i32 %add5, %C
br i1 %cmp6, label %if.then, label %ret.end
; CHECK-LABEL: @noifconvertstore2(
; CHECK-NOT: select
if.then:
store i32 %add5, i32* %arrayidx2, align 4
br label %ret.end
ret.end:
ret void
}
define void @noifconvertstore_volatile(i32 %m, i32* %A, i32* %B, i32 %C, i32 %D) {
entry:
%arrayidx = getelementptr inbounds i32* %B, i64 0
%0 = load i32* %arrayidx, align 4
%add = add nsw i32 %0, %C
%arrayidx2 = getelementptr inbounds i32* %A, i64 0
; First store to the location.
store i32 %add, i32* %arrayidx2, align 4
%arrayidx4 = getelementptr inbounds i32* %B, i64 1
%1 = load i32* %arrayidx4, align 4
%add5 = add nsw i32 %1, %D
%cmp6 = icmp sgt i32 %add5, %C
br i1 %cmp6, label %if.then, label %ret.end
; Make sure we don't speculate volatile stores.
; CHECK-LABEL: @noifconvertstore_volatile(
; CHECK-NOT: select
if.then:
store volatile i32 %add5, i32* %arrayidx2, align 4
br label %ret.end
ret.end:
ret void
}
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