release/20.x: [LV] Fix crash when building partial reductions using types that aren't known scale factors (#136680) #136863
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…'t known scale factors (llvm#136680) (cherry picked from commit 1ce709c)
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@fhahn What do you think about merging this PR to the release branch? |
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@llvm/pr-subscribers-llvm-transforms Author: None (llvmbot) ChangesBackport 1ce709c Requested by: @NickGuy-Arm Full diff: https://github.com/llvm/llvm-project/pull/136863.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 1baec6d6ca37b..3b6166ab1fa9e 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -8778,9 +8778,13 @@ bool VPRecipeBuilder::getScaledReductions(
PartialReductionChain Chain(RdxExitInstr, ExtA, ExtB, BinOp);
- unsigned TargetScaleFactor =
- PHI->getType()->getPrimitiveSizeInBits().getKnownScalarFactor(
- A->getType()->getPrimitiveSizeInBits());
+ TypeSize PHISize = PHI->getType()->getPrimitiveSizeInBits();
+ TypeSize ASize = A->getType()->getPrimitiveSizeInBits();
+
+ if (!PHISize.hasKnownScalarFactor(ASize))
+ return false;
+
+ unsigned TargetScaleFactor = PHISize.getKnownScalarFactor(ASize);
if (LoopVectorizationPlanner::getDecisionAndClampRange(
[&](ElementCount VF) {
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll b/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll
index 3561f52df9490..ef82154dfce66 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll
@@ -59,3 +59,59 @@ for.body: ; preds = %for.body, %entry
for.exit: ; preds = %for.body
ret i32 %add
}
+
+; Test to ensure that we don't crash when evaluating an extend from a type
+; that is not a factor of the target type.
+define i40 @partial_reduce_not_known_factor(i32 %a, i32 %b, i16 %N) {
+; CHECK-LABEL: define i40 @partial_reduce_not_known_factor(
+; CHECK-SAME: i32 [[A:%.*]], i32 [[B:%.*]], i16 [[N:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: [[SMAX:%.*]] = call i16 @llvm.smax.i16(i16 [[N]], i16 0)
+; CHECK-NEXT: [[TMP0:%.*]] = zext nneg i16 [[SMAX]] to i32
+; CHECK-NEXT: [[TMP1:%.*]] = add nuw nsw i32 [[TMP0]], 1
+; CHECK-NEXT: [[MIN_ITERS_CHECK:%.*]] = icmp ult i32 [[TMP1]], 4
+; CHECK-NEXT: br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK: [[VECTOR_PH]]:
+; CHECK-NEXT: [[N_MOD_VF:%.*]] = urem i32 [[TMP1]], 4
+; CHECK-NEXT: [[N_VEC:%.*]] = sub i32 [[TMP1]], [[N_MOD_VF]]
+; CHECK-NEXT: [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i32> poison, i32 [[B]], i64 0
+; CHECK-NEXT: [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i32> [[BROADCAST_SPLATINSERT]], <2 x i32> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT: [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <2 x i32> poison, i32 [[A]], i64 0
+; CHECK-NEXT: [[BROADCAST_SPLAT2:%.*]] = shufflevector <2 x i32> [[BROADCAST_SPLATINSERT1]], <2 x i32> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[N_VEC]] to i16
+; CHECK-NEXT: [[TMP3:%.*]] = sext <2 x i32> [[BROADCAST_SPLAT2]] to <2 x i40>
+; CHECK-NEXT: [[TMP4:%.*]] = sext <2 x i32> [[BROADCAST_SPLAT]] to <2 x i40>
+; CHECK-NEXT: [[TMP5:%.*]] = or <2 x i40> [[TMP4]], [[TMP3]]
+; CHECK-NEXT: br label %[[VECTOR_BODY:.*]]
+; CHECK: [[VECTOR_BODY]]:
+; CHECK-NEXT: [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT: [[VEC_PHI:%.*]] = phi <2 x i40> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT: [[VEC_PHI3:%.*]] = phi <2 x i40> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT: [[TMP6]] = or <2 x i40> [[VEC_PHI]], [[TMP5]]
+; CHECK-NEXT: [[TMP8]] = or <2 x i40> [[VEC_PHI3]], [[TMP5]]
+; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 4
+; CHECK-NEXT: [[TMP7:%.*]] = icmp eq i32 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT: br i1 [[TMP7]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK: [[MIDDLE_BLOCK]]:
+; CHECK-NEXT: [[BIN_RDX:%.*]] = or <2 x i40> [[TMP8]], [[TMP6]]
+; CHECK-NEXT: [[TMP9:%.*]] = call i40 @llvm.vector.reduce.or.v2i40(<2 x i40> [[BIN_RDX]])
+; CHECK-NEXT: [[CMP_N:%.*]] = icmp eq i32 [[TMP1]], [[N_VEC]]
+; CHECK-NEXT: br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+entry:
+ br label %for.body
+
+for.body:
+ %red = phi i40 [ 0, %entry ], [ %1, %for.body ]
+ %iv = phi i16 [ 0, %entry ], [ %iv.next, %for.body ]
+ %resize = sext i32 %a to i40
+ %resize4 = sext i32 %b to i40
+ %0 = or i40 %resize4, %resize
+ %1 = or i40 %red, %0
+ %iv.next = add i16 %iv, 1
+ %cmp = icmp slt i16 %iv, %N
+ br i1 %cmp, label %for.body, label %exit
+
+exit:
+ %result.lcssa = phi i40 [ %1, %for.body ]
+ ret i40 %result.lcssa
+}
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@llvm/pr-subscribers-vectorizers Author: None (llvmbot) ChangesBackport 1ce709c Requested by: @NickGuy-Arm Full diff: https://github.com/llvm/llvm-project/pull/136863.diff 2 Files Affected:
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 1baec6d6ca37b..3b6166ab1fa9e 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -8778,9 +8778,13 @@ bool VPRecipeBuilder::getScaledReductions(
PartialReductionChain Chain(RdxExitInstr, ExtA, ExtB, BinOp);
- unsigned TargetScaleFactor =
- PHI->getType()->getPrimitiveSizeInBits().getKnownScalarFactor(
- A->getType()->getPrimitiveSizeInBits());
+ TypeSize PHISize = PHI->getType()->getPrimitiveSizeInBits();
+ TypeSize ASize = A->getType()->getPrimitiveSizeInBits();
+
+ if (!PHISize.hasKnownScalarFactor(ASize))
+ return false;
+
+ unsigned TargetScaleFactor = PHISize.getKnownScalarFactor(ASize);
if (LoopVectorizationPlanner::getDecisionAndClampRange(
[&](ElementCount VF) {
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll b/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll
index 3561f52df9490..ef82154dfce66 100644
--- a/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/partial-reduce-no-dotprod.ll
@@ -59,3 +59,59 @@ for.body: ; preds = %for.body, %entry
for.exit: ; preds = %for.body
ret i32 %add
}
+
+; Test to ensure that we don't crash when evaluating an extend from a type
+; that is not a factor of the target type.
+define i40 @partial_reduce_not_known_factor(i32 %a, i32 %b, i16 %N) {
+; CHECK-LABEL: define i40 @partial_reduce_not_known_factor(
+; CHECK-SAME: i32 [[A:%.*]], i32 [[B:%.*]], i16 [[N:%.*]]) #[[ATTR0]] {
+; CHECK-NEXT: [[ENTRY:.*]]:
+; CHECK-NEXT: [[SMAX:%.*]] = call i16 @llvm.smax.i16(i16 [[N]], i16 0)
+; CHECK-NEXT: [[TMP0:%.*]] = zext nneg i16 [[SMAX]] to i32
+; CHECK-NEXT: [[TMP1:%.*]] = add nuw nsw i32 [[TMP0]], 1
+; CHECK-NEXT: [[MIN_ITERS_CHECK:%.*]] = icmp ult i32 [[TMP1]], 4
+; CHECK-NEXT: br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK: [[VECTOR_PH]]:
+; CHECK-NEXT: [[N_MOD_VF:%.*]] = urem i32 [[TMP1]], 4
+; CHECK-NEXT: [[N_VEC:%.*]] = sub i32 [[TMP1]], [[N_MOD_VF]]
+; CHECK-NEXT: [[BROADCAST_SPLATINSERT:%.*]] = insertelement <2 x i32> poison, i32 [[B]], i64 0
+; CHECK-NEXT: [[BROADCAST_SPLAT:%.*]] = shufflevector <2 x i32> [[BROADCAST_SPLATINSERT]], <2 x i32> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT: [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <2 x i32> poison, i32 [[A]], i64 0
+; CHECK-NEXT: [[BROADCAST_SPLAT2:%.*]] = shufflevector <2 x i32> [[BROADCAST_SPLATINSERT1]], <2 x i32> poison, <2 x i32> zeroinitializer
+; CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[N_VEC]] to i16
+; CHECK-NEXT: [[TMP3:%.*]] = sext <2 x i32> [[BROADCAST_SPLAT2]] to <2 x i40>
+; CHECK-NEXT: [[TMP4:%.*]] = sext <2 x i32> [[BROADCAST_SPLAT]] to <2 x i40>
+; CHECK-NEXT: [[TMP5:%.*]] = or <2 x i40> [[TMP4]], [[TMP3]]
+; CHECK-NEXT: br label %[[VECTOR_BODY:.*]]
+; CHECK: [[VECTOR_BODY]]:
+; CHECK-NEXT: [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT: [[VEC_PHI:%.*]] = phi <2 x i40> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP6:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT: [[VEC_PHI3:%.*]] = phi <2 x i40> [ zeroinitializer, %[[VECTOR_PH]] ], [ [[TMP8:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT: [[TMP6]] = or <2 x i40> [[VEC_PHI]], [[TMP5]]
+; CHECK-NEXT: [[TMP8]] = or <2 x i40> [[VEC_PHI3]], [[TMP5]]
+; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 4
+; CHECK-NEXT: [[TMP7:%.*]] = icmp eq i32 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT: br i1 [[TMP7]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
+; CHECK: [[MIDDLE_BLOCK]]:
+; CHECK-NEXT: [[BIN_RDX:%.*]] = or <2 x i40> [[TMP8]], [[TMP6]]
+; CHECK-NEXT: [[TMP9:%.*]] = call i40 @llvm.vector.reduce.or.v2i40(<2 x i40> [[BIN_RDX]])
+; CHECK-NEXT: [[CMP_N:%.*]] = icmp eq i32 [[TMP1]], [[N_VEC]]
+; CHECK-NEXT: br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
+entry:
+ br label %for.body
+
+for.body:
+ %red = phi i40 [ 0, %entry ], [ %1, %for.body ]
+ %iv = phi i16 [ 0, %entry ], [ %iv.next, %for.body ]
+ %resize = sext i32 %a to i40
+ %resize4 = sext i32 %b to i40
+ %0 = or i40 %resize4, %resize
+ %1 = or i40 %red, %0
+ %iv.next = add i16 %iv, 1
+ %cmp = icmp slt i16 %iv, %N
+ br i1 %cmp, label %for.body, label %exit
+
+exit:
+ %result.lcssa = phi i40 [ %1, %for.body ]
+ ret i40 %result.lcssa
+}
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This has some test failures. |
fhahn
reviewed
Apr 26, 2025
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I can verify that updating the test files doesn't impact the test itself. Looks to be some instruction reordering but no change to the functionality being tested, and this test passes on main without any further changes. How do we go about updating the test on this branch, as I assume we don't have commit access to llvmbot's fork. |
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@NickGuy-Arm You can do the changes manually and create a new PR. |
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Backport 1ce709c
Requested by: @NickGuy-Arm