mirror of
				https://github.com/c64scene-ar/llvm-6502.git
				synced 2025-11-04 05:17:07 +00:00 
			
		
		
		
	The patch disabled unrolling in loop vectorization pass when VF==1 on x86 architecture, by setting MaxInterleaveFactor to 1. Unrolling in loop vectorization pass may introduce the cost of overflow check, memory boundary check and extra prologue/epilogue code when regular unroller will unroll the loop another time. Disable it when VF==1 remove the unnecessary cost on x86. The same can be done for other platforms after verifying interleaving/memory bound checking to be not perf critical on those platforms. Differential Revision: http://reviews.llvm.org/D9515 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236613 91177308-0d34-0410-b5e6-96231b3b80d8
		
			
				
	
	
		
			38 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
	
	
			
		
		
	
	
			38 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
	
	
; This test makes sure that loop will not be unrolled in vectorization if VF computed
 | 
						|
; equals to 1.
 | 
						|
; RUN: opt < %s -loop-vectorize -S | FileCheck %s
 | 
						|
 | 
						|
; Make sure there are no geps being merged.
 | 
						|
; CHECK-LABEL: @foo(
 | 
						|
; CHECK: getelementptr
 | 
						|
; CHECK-NOT: getelementptr
 | 
						|
 | 
						|
@N = common global i32 0, align 4
 | 
						|
@a = common global [1000 x i32] zeroinitializer, align 16
 | 
						|
 | 
						|
define void @foo() #0 {
 | 
						|
entry:
 | 
						|
  %0 = load i32, i32* @N, align 4
 | 
						|
  %cmp5 = icmp sgt i32 %0, 0
 | 
						|
  br i1 %cmp5, label %for.body.lr.ph, label %for.end
 | 
						|
 | 
						|
for.body.lr.ph:                                   ; preds = %entry
 | 
						|
  %conv = sext i32 %0 to i64
 | 
						|
  br label %for.body
 | 
						|
 | 
						|
for.body:                                         ; preds = %for.body.lr.ph, %for.body
 | 
						|
  %i.06 = phi i64 [ 0, %for.body.lr.ph ], [ %inc, %for.body ]
 | 
						|
  %mul = mul nuw nsw i64 %i.06, 7
 | 
						|
  %arrayidx = getelementptr inbounds [1000 x i32], [1000 x i32]* @a, i64 0, i64 %mul
 | 
						|
  store i32 3, i32* %arrayidx, align 4
 | 
						|
  %inc = add nuw nsw i64 %i.06, 1
 | 
						|
  %cmp = icmp slt i64 %inc, %conv
 | 
						|
  br i1 %cmp, label %for.body, label %for.end.loopexit
 | 
						|
 | 
						|
for.end.loopexit:                                 ; preds = %for.body
 | 
						|
  br label %for.end
 | 
						|
 | 
						|
for.end:                                          ; preds = %for.end.loopexit, %entry
 | 
						|
  ret void
 | 
						|
}
 |