You've already forked linux-packaging-mono
							
							
		
			
				
	
	
		
			60 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			LLVM
		
	
	
	
	
	
| ; RUN: llc -march=hexagon < %s | FileCheck %s
 | |
| 
 | |
| ; DAG combiner folds sequences of shifts, which can sometimes obscure
 | |
| ; optimization opportunities. For example
 | |
| ;
 | |
| ;   unsigned int c(unsigned int b, unsigned int *a) {
 | |
| ;     unsigned int bitidx = b >> 5;
 | |
| ;     return a[bitidx];
 | |
| ;   }
 | |
| ;
 | |
| ; produces
 | |
| ;   (add x (shl (srl y 5) 2))
 | |
| ; which is then folded into
 | |
| ;   (add x (and (srl y 3) 1FFFFFFC))
 | |
| ;
 | |
| ; That results in a constant-extended and:
 | |
| ;   r0 = and(##536870908,lsr(r0,#3))
 | |
| ;   r0 = memw(r1+r0<<#0)
 | |
| ; whereas
 | |
| ;   r0 = lsr(r0,#5)
 | |
| ;   r0 = memw(r1+r0<<#2)
 | |
| ; is more desirable.
 | |
| 
 | |
| target triple = "hexagon"
 | |
| 
 | |
| ; CHECK-LABEL: load_0
 | |
| ; CHECK: memw(r{{[0-9]+}}+r{{[0-9]}}<<#2)
 | |
| define i32 @load_0(i32 %b, i32* nocapture readonly %a) #0 {
 | |
| entry:
 | |
|   %shr = lshr i32 %b, 5
 | |
|   %arrayidx = getelementptr inbounds i32, i32* %a, i32 %shr
 | |
|   %0 = load i32, i32* %arrayidx, align 4
 | |
|   ret i32 %0
 | |
| }
 | |
| 
 | |
| ; This would require r0<<#3, which is not legal.
 | |
| ; CHECK-LABEL: load_1
 | |
| ; CHECK: memw(r{{[0-9]+}}+r{{[0-9]}}<<#0)
 | |
| define i32 @load_1(i32 %b, [3 x i32]* nocapture readonly %a) #0 {
 | |
| entry:
 | |
|   %shr = lshr i32 %b, 5
 | |
|   %arrayidx = getelementptr inbounds [3 x i32], [3 x i32]* %a, i32 %shr, i32 0
 | |
|   %0 = load i32, i32* %arrayidx, align 4
 | |
|   ret i32 %0
 | |
| }
 | |
| 
 | |
| ; CHECK-LABEL: store_0
 | |
| ; CHECK: memw(r{{[0-9]+}}+r{{[0-9]}}<<#2)
 | |
| define void @store_0(i32 %b, i32* nocapture %a, i32 %v) #1 {
 | |
| entry:
 | |
|   %shr = lshr i32 %b, 5
 | |
|   %arrayidx = getelementptr inbounds i32, i32* %a, i32 %shr
 | |
|   store i32 %v, i32* %arrayidx, align 4
 | |
|   ret void
 | |
| }
 | |
| 
 | |
| attributes #0 = { norecurse nounwind readonly "target-cpu"="hexagonv60" "target-features"="-hvx,-long-calls" }
 | |
| attributes #1 = { norecurse nounwind "target-cpu"="hexagonv60" "target-features"="-hvx,-long-calls" }
 | |
| 
 |