36 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; This testcase ensures that CFL AA answers queries soundly when callee tries 
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| ; to return the reference of one of its parameters
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| 
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| ; RUN: opt < %s -disable-basicaa -cfl-steens-aa -aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s
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| ; RUN: opt < %s -aa-pipeline=cfl-steens-aa -passes=aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s
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| 
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| declare noalias i8* @malloc(i64)
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| 
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| define i32** @return_ref_arg_callee(i32* %arg1) {
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| 	%ptr = call noalias i8* @malloc(i64 8)
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| 	%ptr_cast = bitcast i8* %ptr to i32**
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| 	store i32* %arg1, i32** %ptr_cast
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| 	ret i32** %ptr_cast
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| }
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| ; CHECK-LABEL: Function: test_return_ref_arg
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| ; CHECK: MayAlias: i32* %a, i32* %lb
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| ; CHECK: NoAlias: i32* %lb, i32** %p
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| ; CHECK: NoAlias: i32* %lb, i32** %b
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| ; CHECK: NoAlias: i32* %lp, i32** %p
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| ; CHECK: NoAlias: i32* %lp, i32** %b
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| ; CHECK: MayAlias: i32* %lb, i32* %lp
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| 
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| ; We could've proven the following facts if the analysis were inclusion-based:
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| ; NoAlias: i32** %b, i32** %p
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| define void @test_return_ref_arg() {
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|   %a = alloca i32, align 4
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|   %p = alloca i32*, align 8
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| 
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|   store i32* %a, i32** %p
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|   %b = call i32** @return_ref_arg_callee(i32* %a)
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| 
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|   %lb = load i32*, i32** %b
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|   %lp = load i32*, i32** %p
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| 
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|   ret void
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| } |