forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			48 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			48 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: llc < %s -march=arm | FileCheck %s
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| 
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| ; This loop is rewritten with an indvar which counts down, which
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| ; frees up a register from holding the trip count.
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| 
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| define void @test(i32* %P, i32 %A, i32 %i) nounwind {
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| entry:
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| ; CHECK: str r1, [{{r.*}}, {{r.*}}, lsl #2]
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|         icmp eq i32 %i, 0               ; <i1>:0 [#uses=1]
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|         br i1 %0, label %return, label %bb
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| 
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| bb:             ; preds = %bb, %entry
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|         %indvar = phi i32 [ 0, %entry ], [ %indvar.next, %bb ]          ; <i32> [#uses=2]
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|         %i_addr.09.0 = sub i32 %i, %indvar              ; <i32> [#uses=1]
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|         %tmp2 = getelementptr i32* %P, i32 %i_addr.09.0         ; <i32*> [#uses=1]
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|         store i32 %A, i32* %tmp2
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|         %indvar.next = add i32 %indvar, 1               ; <i32> [#uses=2]
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|         icmp eq i32 %indvar.next, %i            ; <i1>:1 [#uses=1]
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|         br i1 %1, label %return, label %bb
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| 
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| return:         ; preds = %bb, %entry
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|         ret void
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| }
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| 
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| ; This loop has a non-address use of the count-up indvar, so
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| ; it'll remain. Now the original store uses a negative-stride address.
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| 
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| define void @test_with_forced_iv(i32* %P, i32 %A, i32 %i) nounwind {
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| entry:
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| ; CHECK: str r1, [{{r.*}}, -{{r.*}}, lsl #2]
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|         icmp eq i32 %i, 0               ; <i1>:0 [#uses=1]
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|         br i1 %0, label %return, label %bb
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| 
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| bb:             ; preds = %bb, %entry
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|         %indvar = phi i32 [ 0, %entry ], [ %indvar.next, %bb ]          ; <i32> [#uses=2]
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|         %i_addr.09.0 = sub i32 %i, %indvar              ; <i32> [#uses=1]
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|         %tmp2 = getelementptr i32* %P, i32 %i_addr.09.0         ; <i32*> [#uses=1]
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|         store i32 %A, i32* %tmp2
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|         store i32 %indvar, i32* null
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|         %indvar.next = add i32 %indvar, 1               ; <i32> [#uses=2]
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|         icmp eq i32 %indvar.next, %i            ; <i1>:1 [#uses=1]
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|         br i1 %1, label %return, label %bb
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| 
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| return:         ; preds = %bb, %entry
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|         ret void
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| }
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| 
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