df1838f5d9
When -polly-annotate-metadata-vectorize is active, Polly marks its generated loops with llvm.loop.vectorize.enable=true. This is harmful for loops with a loop-carried dependence of distance 1 that involve floating-point operations: the Loop Vectorizer reorders FP operations (e.g. scalar reduction like q = factor*q), producing results that differ from the sequential scalar reference and causing correctness failures. Two changes are made: 1. IslAst.cpp: add PollyVectorizeMetadata to the PerformParallelTest gate so that dependence-distance computation is performed whenever -polly-annotate-metadata-vectorize is passed, not only when -polly-parallel or a vectorizer is active. 2. IslNodeBuilder.cpp / LoopGenerators.cpp: when a loop has a dist=1 dependence involving FP operations, omit the vectorize.enable annotation entirely. This lets the Loop Vectorizer apply its own cost model and legality checks decide.
61 lines
2.7 KiB
LLVM
61 lines
2.7 KiB
LLVM
; RUN: opt %loadNPMPolly -S '-passes=polly<no-default-opts>' -polly-annotate-metadata-vectorize < %s | FileCheck %s
|
|
|
|
; Basic verification of vectorize metadata getting added when "-polly-vectorize-metadata" is
|
|
; passed.
|
|
|
|
; void add(int *A, int *B, int *C,int n) {
|
|
; for(int i=0; i<n; i++)
|
|
; C[i] += A[i] + B[i];
|
|
; }
|
|
|
|
; CHECK: for.body:
|
|
; CHECK: br {{.*}} !llvm.loop [[LOOP:![0-9]+]]
|
|
; CHECK: polly.stmt.for.body:
|
|
; CHECK: br {{.*}} !llvm.loop [[POLLY_LOOP:![0-9]+]]
|
|
; CHECK: [[LOOP]] = distinct !{[[LOOP]], [[META2:![0-9]+]], [[META3:![0-9]+]]}
|
|
; CHECK: [[META3]] = !{!"llvm.loop.vectorize.enable", i32 0}
|
|
; CHECK: [[POLLY_LOOP]] = distinct !{[[POLLY_LOOP]], {{.*}}}
|
|
; CHECK-DAG: !{!"llvm.loop.vectorize.enable", i1 true}
|
|
|
|
target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32"
|
|
target triple = "aarch64-unknown-linux-gnu"
|
|
|
|
; Function Attrs: nofree norecurse nosync nounwind memory(argmem: readwrite) uwtable
|
|
define dso_local void @add(ptr nocapture noundef readonly %A, ptr nocapture noundef readonly %B, ptr nocapture noundef %C, i32 noundef %n) local_unnamed_addr #0 {
|
|
entry:
|
|
br label %entry.split
|
|
|
|
entry.split: ; preds = %entry
|
|
%cmp10 = icmp sgt i32 %n, 0
|
|
br i1 %cmp10, label %for.body.preheader, label %for.cond.cleanup
|
|
|
|
for.body.preheader: ; preds = %entry.split
|
|
%wide.trip.count = zext nneg i32 %n to i64
|
|
br label %for.body
|
|
|
|
for.cond.cleanup.loopexit: ; preds = %for.body
|
|
br label %for.cond.cleanup
|
|
|
|
for.cond.cleanup: ; preds = %for.cond.cleanup.loopexit, %entry.split
|
|
ret void
|
|
|
|
for.body: ; preds = %for.body.preheader, %for.body
|
|
%indvars.iv = phi i64 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
|
|
%arrayidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
|
|
%0 = load i32, ptr %arrayidx, align 4
|
|
%arrayidx2 = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
|
|
%1 = load i32, ptr %arrayidx2, align 4
|
|
%add = add nsw i32 %1, %0
|
|
%arrayidx4 = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
|
|
%2 = load i32, ptr %arrayidx4, align 4
|
|
%add5 = add nsw i32 %add, %2
|
|
store i32 %add5, ptr %arrayidx4, align 4
|
|
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
|
|
%exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
|
|
br i1 %exitcond.not, label %for.cond.cleanup.loopexit, label %for.body, !llvm.loop !0
|
|
}
|
|
|
|
attributes #0 = { nofree norecurse nosync nounwind memory(argmem: readwrite) uwtable "frame-pointer"="non-leaf" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="cortex-a57" "target-features"="+aes,+crc,+fp-armv8,+neon,+outline-atomics,+perfmon,+sha2,+v8a,-fmv" }
|
|
|
|
!0 = distinct !{!0, !1}
|
|
!1 = !{!"llvm.loop.mustprogress"}
|