gvn.ll
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; RUN: opt -S -basic-aa -objc-arc-aa -gvn < %s | FileCheck %s
@x = common global i8* null, align 8
declare i8* @llvm.objc.retain(i8*)
declare i32 @llvm.objc.sync.enter(i8*)
declare i32 @llvm.objc.sync.exit(i8*)
; GVN should be able to eliminate this redundant load, with ARC-specific
; alias analysis.
; CHECK: define i8* @test0(i32 %n)
; CHECK-NEXT: entry:
; CHECK-NEXT: %s = load i8*, i8** @x
; CHECK-NOT: load
; CHECK: ret i8* %s
; CHECK-NEXT: }
define i8* @test0(i32 %n) nounwind {
entry:
%s = load i8*, i8** @x
%0 = tail call i8* @llvm.objc.retain(i8* %s) nounwind
%t = load i8*, i8** @x
ret i8* %t
}
; GVN should not be able to eliminate this redundant load, with ARC-specific
; alias analysis.
; CHECK-LABEL: define i8* @test1(
; CHECK: load
; CHECK: load
; CHECK: ret i8* %t
; CHECK: }
define i8* @test1(i32 %n) nounwind {
entry:
%s = load i8*, i8** @x
%0 = call i32 @llvm.objc.sync.enter(i8* %s)
%t = load i8*, i8** @x
%1 = call i32 @llvm.objc.sync.exit(i8* %s)
ret i8* %t
}