llvm-6502/test/Transforms/LoopVectorize/read-only.ll
Nadav Rotem bf8772ed2c Vectorize: teach cavVectorizeMemory to distinguish between A[i]+=x and A[B[i]]+=x.
If the pointer is consecutive then it is safe to read and write. If the pointer is non-loop-consecutive then
it is unsafe to vectorize it because we may hit an ordering issue.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166371 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-20 08:26:33 +00:00

33 lines
1.3 KiB
LLVM

; RUN: opt < %s -loop-vectorize -dce -instcombine -licm -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.8.0"
;CHECK: @read_only_func
;CHECK: load <4 x i32>
;CHECK: ret i32
define i32 @read_only_func(i32* nocapture %A, i32* nocapture %B, i32 %n) nounwind uwtable readonly ssp {
%1 = icmp sgt i32 %n, 0
br i1 %1, label %.lr.ph, label %._crit_edge
.lr.ph: ; preds = %0, %.lr.ph
%indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
%sum.02 = phi i32 [ %9, %.lr.ph ], [ 0, %0 ]
%2 = getelementptr inbounds i32* %A, i64 %indvars.iv
%3 = load i32* %2, align 4
%4 = add nsw i64 %indvars.iv, 13
%5 = getelementptr inbounds i32* %B, i64 %4
%6 = load i32* %5, align 4
%7 = shl i32 %6, 1
%8 = add i32 %3, %sum.02
%9 = add i32 %8, %7
%indvars.iv.next = add i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, %n
br i1 %exitcond, label %._crit_edge, label %.lr.ph
._crit_edge: ; preds = %.lr.ph, %0
%sum.0.lcssa = phi i32 [ 0, %0 ], [ %9, %.lr.ph ]
ret i32 %sum.0.lcssa
}