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| ; RUN: opt -instcombine -S < %s | FileCheck %s
target datalayout = "e-m:e-p:32:32-f64:32:64-f80:32-n8:16:32-S128"
target triple = "i686-unknown-linux-gnu"
; Check that instcombine doesn't sink dynamic allocas across llvm.stacksave.
; Helper to generate branch conditions.
declare i1 @cond()
declare i32* @use_and_return(i32*)
declare i8* @llvm.stacksave() #0
declare void @llvm.stackrestore(i8*) #0
define void @foo(i32 %x) {
entry:
%c1 = call i1 @cond()
br i1 %c1, label %ret, label %nonentry
nonentry: ; preds = %entry
%argmem = alloca i32, i32 %x, align 4
%sp = call i8* @llvm.stacksave()
%c2 = call i1 @cond()
br i1 %c2, label %ret, label %sinktarget
sinktarget: ; preds = %nonentry
; Arrange for there to be a single use of %argmem by returning it.
%p = call i32* @use_and_return(i32* nonnull %argmem)
store i32 13, i32* %p, align 4
call void @llvm.stackrestore(i8* %sp)
%0 = call i32* @use_and_return(i32* %p)
br label %ret
ret: ; preds = %sinktarget, %nonentry, %entry
ret void
}
; CHECK-LABEL: define void @foo(i32 %x)
; CHECK: nonentry:
; CHECK: %argmem = alloca i32, i32 %x
; CHECK: %sp = call i8* @llvm.stacksave()
; CHECK: %c2 = call i1 @cond()
; CHECK: br i1 %c2, label %ret, label %sinktarget
; CHECK: sinktarget:
; CHECK: %p = call i32* @use_and_return(i32* nonnull %argmem)
; CHECK: store i32 13, i32* %p
; CHECK: call void @llvm.stackrestore(i8* %sp)
; CHECK: %0 = call i32* @use_and_return(i32* %p)
attributes #0 = { nounwind }
|