Skip to content

[VPlan] Avoid sinking allocas in sinkScalarOperands #166135

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Nov 5, 2025
+8 −6
Merged

[VPlan] Avoid sinking allocas in sinkScalarOperands #166135

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 1 addition & 2 deletions llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -167,8 +167,7 @@ static bool sinkScalarOperands(VPlan &Plan) {
if (!isa<VPReplicateRecipe, VPScalarIVStepsRecipe>(Candidate))
return;

if (Candidate->getParent() == SinkTo || Candidate->mayHaveSideEffects() ||
Candidate->mayReadOrWriteMemory())
if (Candidate->getParent() == SinkTo || cannotHoistOrSinkRecipe(*Candidate))
return;

if (auto *RepR = dyn_cast<VPReplicateRecipe>(Candidate))
Expand Down
11 changes: 7 additions & 4 deletions llvm/test/Transforms/LoopVectorize/tail-folding-alloca-in-loop.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,12 +12,15 @@ define i32 @test(ptr %vf1, i64 %n) {
; CHECK-NEXT: [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[PRED_STORE_CONTINUE6:.*]] ]
; CHECK-NEXT: [[VEC_IND:%.*]] = phi <4 x i8> [ <i8 0, i8 1, i8 2, i8 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[PRED_STORE_CONTINUE6]] ]
; CHECK-NEXT: [[TMP0:%.*]] = icmp ule <4 x i8> [[VEC_IND]], splat (i8 -56)
; CHECK-NEXT: [[TMP18:%.*]] = alloca i8, i64 [[N]], align 16
; CHECK-NEXT: [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x ptr> poison, ptr [[TMP18]], i64 0
; CHECK-NEXT: [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x ptr> [[BROADCAST_SPLATINSERT]], <4 x ptr> poison, <4 x i32> zeroinitializer
; CHECK-NEXT: [[TMP1:%.*]] = extractelement <4 x i1> [[TMP0]], i32 0
; CHECK-NEXT: br i1 [[TMP1]], label %[[PRED_STORE_IF:.*]], label %[[PRED_STORE_CONTINUE:.*]]
; CHECK: [[PRED_STORE_IF]]:
; CHECK-NEXT: [[TMP2:%.*]] = add i64 [[INDEX]], 0
; CHECK-NEXT: [[TMP3:%.*]] = getelementptr inbounds ptr, ptr [[VF1]], i64 [[TMP2]]
; CHECK-NEXT: [[TMP4:%.*]] = alloca i8, i64 [[N]], align 16
; CHECK-NEXT: [[TMP4:%.*]] = extractelement <4 x ptr> [[BROADCAST_SPLAT]], i32 0
; CHECK-NEXT: store ptr [[TMP4]], ptr [[TMP3]], align 8
; CHECK-NEXT: br label %[[PRED_STORE_CONTINUE]]
; CHECK: [[PRED_STORE_CONTINUE]]:
Expand All @@ -26,7 +29,7 @@ define i32 @test(ptr %vf1, i64 %n) {
; CHECK: [[PRED_STORE_IF1]]:
; CHECK-NEXT: [[TMP6:%.*]] = add i64 [[INDEX]], 1
; CHECK-NEXT: [[TMP7:%.*]] = getelementptr inbounds ptr, ptr [[VF1]], i64 [[TMP6]]
; CHECK-NEXT: [[TMP8:%.*]] = alloca i8, i64 [[N]], align 16
; CHECK-NEXT: [[TMP8:%.*]] = extractelement <4 x ptr> [[BROADCAST_SPLAT]], i32 0
; CHECK-NEXT: store ptr [[TMP8]], ptr [[TMP7]], align 8
; CHECK-NEXT: br label %[[PRED_STORE_CONTINUE2]]
; CHECK: [[PRED_STORE_CONTINUE2]]:
Expand All @@ -35,7 +38,7 @@ define i32 @test(ptr %vf1, i64 %n) {
; CHECK: [[PRED_STORE_IF3]]:
; CHECK-NEXT: [[TMP10:%.*]] = add i64 [[INDEX]], 2
; CHECK-NEXT: [[TMP11:%.*]] = getelementptr inbounds ptr, ptr [[VF1]], i64 [[TMP10]]
; CHECK-NEXT: [[TMP12:%.*]] = alloca i8, i64 [[N]], align 16
; CHECK-NEXT: [[TMP12:%.*]] = extractelement <4 x ptr> [[BROADCAST_SPLAT]], i32 0
; CHECK-NEXT: store ptr [[TMP12]], ptr [[TMP11]], align 8
; CHECK-NEXT: br label %[[PRED_STORE_CONTINUE4]]
; CHECK: [[PRED_STORE_CONTINUE4]]:
Expand All @@ -44,7 +47,7 @@ define i32 @test(ptr %vf1, i64 %n) {
; CHECK: [[PRED_STORE_IF5]]:
; CHECK-NEXT: [[TMP14:%.*]] = add i64 [[INDEX]], 3
; CHECK-NEXT: [[TMP15:%.*]] = getelementptr inbounds ptr, ptr [[VF1]], i64 [[TMP14]]
; CHECK-NEXT: [[TMP16:%.*]] = alloca i8, i64 [[N]], align 16
; CHECK-NEXT: [[TMP16:%.*]] = extractelement <4 x ptr> [[BROADCAST_SPLAT]], i32 0
; CHECK-NEXT: store ptr [[TMP16]], ptr [[TMP15]], align 8
; CHECK-NEXT: br label %[[PRED_STORE_CONTINUE6]]
; CHECK: [[PRED_STORE_CONTINUE6]]:
Expand Down
Loading