18 lines
		
	
	
		
			823 B
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			18 lines
		
	
	
		
			823 B
		
	
	
	
		
			C
		
	
	
	
| // RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s | FileCheck %s
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| 
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| // It could hit in @llvm.memcpy with "-triple x86_64-(mingw32|win32)".
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| // CHECK-NOT: readonly
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| // CHECK-NOT: readnone
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| 
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| // The struct being passed byval means that we cannot mark the
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| // function readnone.  Readnone would allow stores to the arg to
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| // be deleted in the caller.  We also don't allow readonly since
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| // the callee might write to the byval parameter.  The inliner
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| // would have to assume the worse and introduce an explicit
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| // temporary when inlining such a function, which is costly for
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| // the common case in which the byval argument is not written.
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| struct S { int A[1000]; };
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| int __attribute__ ((const)) f(struct S x) { x.A[1] = 0; return x.A[0]; }
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| int g(struct S x) __attribute__ ((pure));
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| int h(struct S x) { return g(x); }
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