49 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			49 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
| // RUN: %clang_cc1 %s -triple x86_64-apple-darwin -emit-llvm -o - | FileCheck %s
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| // Exercise various use cases for local asm "register variables".
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| 
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| int foo() {
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| // CHECK-LABEL: define i32 @foo()
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| // CHECK: [[A:%[a-zA-Z0-9]+]] = alloca i32
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| 
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|   register int a asm("rsi")=5;
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| // CHECK: store i32 5, i32* [[A]]
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| 
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|   asm volatile("; %0 This asm defines rsi" : "=r"(a));
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| // CHECK: [[Z:%[a-zA-Z0-9]+]] = call i32 asm sideeffect "; $0 This asm defines rsi", "={rsi},~{dirflag},~{fpsr},~{flags}"()
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| // CHECK: store i32 [[Z]], i32* [[A]]
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| 
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|   a = 42;
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| // CHECK:  store i32 42, i32* [[A]]
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| 
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|   asm volatile("; %0 This asm uses rsi" : : "r"(a));
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| // CHECK:  [[TMP:%[a-zA-Z0-9]+]] = load i32, i32* [[A]]
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| // CHECK:  call void asm sideeffect "; $0 This asm uses rsi", "{rsi},~{dirflag},~{fpsr},~{flags}"(i32 [[TMP]])
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| 
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|   return a;
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| // CHECK:  [[TMP1:%[a-zA-Z0-9]+]] = load i32, i32* [[A]]
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| // CHECK:  ret i32 [[TMP1]]
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| }
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| 
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| int earlyclobber() {
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| // CHECK-LABEL: define i32 @earlyclobber()
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| // CHECK: [[A:%[a-zA-Z0-9]+]] = alloca i32
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| 
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|   register int a asm("rsi")=5;
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| // CHECK: store i32 5, i32* [[A]]
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| 
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|   asm volatile("; %0 This asm defines rsi" : "=&r"(a));
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| // CHECK: [[Z:%[a-zA-Z0-9]+]] = call i32 asm sideeffect "; $0 This asm defines rsi", "=&{rsi},~{dirflag},~{fpsr},~{flags}"()
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| // CHECK: store i32 [[Z]], i32* [[A]]
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| 
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|   a = 42;
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| // CHECK:  store i32 42, i32* [[A]]
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| 
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|   asm volatile("; %0 This asm uses rsi" : : "r"(a));
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| // CHECK:  [[TMP:%[a-zA-Z0-9]+]] = load i32, i32* [[A]]
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| // CHECK:  call void asm sideeffect "; $0 This asm uses rsi", "{rsi},~{dirflag},~{fpsr},~{flags}"(i32 [[TMP]])
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| 
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|   return a;
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| // CHECK:  [[TMP1:%[a-zA-Z0-9]+]] = load i32, i32* [[A]]
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| // CHECK:  ret i32 [[TMP1]]
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| }
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