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	Summary: If the src, dst and size of a memcpy are known to be 4 byte aligned we can call __memcpy_4() instead of memcpy(). Reviewers: robertlytton Reviewed By: robertlytton CC: llvm-commits Differential Revision: http://llvm-reviews.chandlerc.com/D2871 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202395 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			33 lines
		
	
	
		
			956 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			33 lines
		
	
	
		
			956 B
		
	
	
	
		
			LLVM
		
	
	
	
	
	
| ; RUN: llc < %s -march=xcore | FileCheck %s
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| 
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| ; Optimize memcpy to __memcpy_4 if src, dst and size are all 4 byte aligned.
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| define void @f1(i8* %dst, i8* %src, i32 %n) nounwind {
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| ; CHECK-LABEL: f1:
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| ; CHECK: bl __memcpy_4
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| entry:
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|   %0 = shl i32 %n, 2
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|   call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %0, i32 4, i1 false)
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|   ret void
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| }
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| 
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| ; Can't optimize - size is not a multiple of 4.
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| define void @f2(i8* %dst, i8* %src, i32 %n) nounwind {
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| ; CHECK-LABEL: f2:
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| ; CHECK: bl memcpy
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| entry:
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|   call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %n, i32 4, i1 false)
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|   ret void
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| }
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| 
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| ; Can't optimize - alignment is not a multiple of 4.
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| define void @f3(i8* %dst, i8* %src, i32 %n) nounwind {
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| ; CHECK-LABEL: f3:
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| ; CHECK: bl memcpy
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| entry:
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|   %0 = shl i32 %n, 2
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|   call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %0, i32 2, i1 false)
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|   ret void
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| }
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| 
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| declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
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