[LLVM][ConstantFolding] Extend constantFoldVectorReduce to include scalable vectors. #165437

paulwalker-arm · 2025-10-28T16:57:36Z

No description provided.

…alable vectors.

llvmbot · 2025-10-28T16:58:10Z

@llvm/pr-subscribers-llvm-transforms

@llvm/pr-subscribers-llvm-analysis

Author: Paul Walker (paulwalker-arm)

Changes

Full diff: https://github.com/llvm/llvm-project/pull/165437.diff

2 Files Affected:

(modified) llvm/lib/Analysis/ConstantFolding.cpp (+30-9)
(modified) llvm/test/Transforms/InstSimplify/ConstProp/vecreduce.ll (+34-50)

diff --git a/llvm/lib/Analysis/ConstantFolding.cpp b/llvm/lib/Analysis/ConstantFolding.cpp
index e9e2e7d0316c7..bd84bd1a14113 100755
--- a/llvm/lib/Analysis/ConstantFolding.cpp
+++ b/llvm/lib/Analysis/ConstantFolding.cpp
@@ -2163,18 +2163,39 @@ Constant *ConstantFoldBinaryFP(double (*NativeFP)(double, double),
 }
 
 Constant *constantFoldVectorReduce(Intrinsic::ID IID, Constant *Op) {
-  FixedVectorType *VT = dyn_cast<FixedVectorType>(Op->getType());
-  if (!VT)
-    return nullptr;
-
-  // This isn't strictly necessary, but handle the special/common case of zero:
-  // all integer reductions of a zero input produce zero.
-  if (isa<ConstantAggregateZero>(Op))
-    return ConstantInt::get(VT->getElementType(), 0);
+  auto *OpVT = cast<VectorType>(Op->getType());
 
   // This is the same as the underlying binops - poison propagates.
   if (isa<PoisonValue>(Op) || Op->containsPoisonElement())
-    return PoisonValue::get(VT->getElementType());
+    return PoisonValue::get(OpVT->getElementType());
+
+  // Shortcut non-accumulating reductions.
+  if (Constant *SplatVal = Op->getSplatValue()) {
+    switch (IID) {
+    case Intrinsic::vector_reduce_and:
+    case Intrinsic::vector_reduce_or:
+    case Intrinsic::vector_reduce_smin:
+    case Intrinsic::vector_reduce_smax:
+    case Intrinsic::vector_reduce_umin:
+    case Intrinsic::vector_reduce_umax:
+      return SplatVal;
+    case Intrinsic::vector_reduce_add:
+    case Intrinsic::vector_reduce_mul:
+      if (SplatVal->isZeroValue())
+        return SplatVal;
+      break;
+    case Intrinsic::vector_reduce_xor:
+      if (SplatVal->isZeroValue())
+        return SplatVal;
+      if (OpVT->getElementCount().isKnownMultipleOf(2))
+        return Constant::getNullValue(OpVT->getElementType());
+      break;
+    }
+  }
+
+  FixedVectorType *VT = dyn_cast<FixedVectorType>(OpVT);
+  if (!VT)
+    return nullptr;
 
   // TODO: Handle undef.
   auto *EltC = dyn_cast_or_null<ConstantInt>(Op->getAggregateElement(0U));
diff --git a/llvm/test/Transforms/InstSimplify/ConstProp/vecreduce.ll b/llvm/test/Transforms/InstSimplify/ConstProp/vecreduce.ll
index 77a7f0d4e4acf..1ba8b0eff1d1a 100644
--- a/llvm/test/Transforms/InstSimplify/ConstProp/vecreduce.ll
+++ b/llvm/test/Transforms/InstSimplify/ConstProp/vecreduce.ll
@@ -12,8 +12,7 @@ define i32 @add_0() {
 
 define i32 @add_0_scalable_vector() {
 ; CHECK-LABEL: @add_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.add.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.add.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -89,8 +88,7 @@ define i32 @add_poison() {
 
 define i32 @add_poison_scalable_vector() {
 ; CHECK-LABEL: @add_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.add.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.add.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -123,8 +121,7 @@ define i32 @mul_0() {
 
 define i32 @mul_0_scalable_vector() {
 ; CHECK-LABEL: @mul_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.mul.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.mul.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -200,8 +197,7 @@ define i32 @mul_poison() {
 
 define i32 @mul_poison_scalable_vector() {
 ; CHECK-LABEL: @mul_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.mul.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.mul.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -225,8 +221,7 @@ define i32 @and_0() {
 
 define i32 @and_0_scalable_vector() {
 ; CHECK-LABEL: @and_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.and.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.and.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -242,8 +237,7 @@ define i32 @and_1() {
 
 define i32 @and_1_scalable_vector() {
 ; CHECK-LABEL: @and_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.and.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 1
 ;
   %x = call i32 @llvm.vector.reduce.and.nxv8i32(<vscale x 8 x i32> splat (i32 1))
   ret i32 %x
@@ -302,8 +296,7 @@ define i32 @and_poison() {
 
 define i32 @and_poison_scalable_vector() {
 ; CHECK-LABEL: @and_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.and.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.and.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -327,8 +320,7 @@ define i32 @or_0() {
 
 define i32 @or_0_scalable_vector() {
 ; CHECK-LABEL: @or_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.or.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.or.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -344,8 +336,7 @@ define i32 @or_1() {
 
 define i32 @or_1_scalable_vector() {
 ; CHECK-LABEL: @or_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.or.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 1
 ;
   %x = call i32 @llvm.vector.reduce.or.nxv8i32(<vscale x 8 x i32> splat (i32 1))
   ret i32 %x
@@ -404,8 +395,7 @@ define i32 @or_poison() {
 
 define i32 @or_poison_scalable_vector() {
 ; CHECK-LABEL: @or_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.or.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.or.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -429,8 +419,7 @@ define i32 @xor_0() {
 
 define i32 @xor_0_scalable_vector() {
 ; CHECK-LABEL: @xor_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -446,13 +435,21 @@ define i32 @xor_1() {
 
 define i32 @xor_1_scalable_vector() {
 ; CHECK-LABEL: @xor_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 8 x i32> splat(i32 1))
   ret i32 %x
 }
 
+define i32 @xor_1_scalable_vector_lane_count_not_known_even() {
+; CHECK-LABEL: @xor_1_scalable_vector_lane_count_not_known_even(
+; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.xor.nxv1i32(<vscale x 1 x i32> splat (i32 1))
+; CHECK-NEXT:    ret i32 [[X]]
+;
+  %x = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 1 x i32> splat(i32 1))
+  ret i32 %x
+}
+
 define i32 @xor_inc() {
 ; CHECK-LABEL: @xor_inc(
 ; CHECK-NEXT:    ret i32 10
@@ -506,8 +503,7 @@ define i32 @xor_poison() {
 
 define i32 @xor_poison_scalable_vector() {
 ; CHECK-LABEL: @xor_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.xor.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -531,8 +527,7 @@ define i32 @smin_0() {
 
 define i32 @smin_0_scalable_vector() {
 ; CHECK-LABEL: @smin_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.smin.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.smin.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -548,8 +543,7 @@ define i32 @smin_1() {
 
 define i32 @smin_1_scalable_vector() {
 ; CHECK-LABEL: @smin_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.smin.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 1
 ;
   %x = call i32 @llvm.vector.reduce.smin.nxv8i32(<vscale x 8 x i32> splat(i32 1))
   ret i32 %x
@@ -608,8 +602,7 @@ define i32 @smin_poison() {
 
 define i32 @smin_poison_scalable_vector() {
 ; CHECK-LABEL: @smin_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.smin.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.smin.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -633,8 +626,7 @@ define i32 @smax_0() {
 
 define i32 @smax_0_scalable_vector() {
 ; CHECK-LABEL: @smax_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.smax.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.smax.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -650,8 +642,7 @@ define i32 @smax_1() {
 
 define i32 @smax_1_scalable_vector() {
 ; CHECK-LABEL: @smax_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.smax.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 1
 ;
   %x = call i32 @llvm.vector.reduce.smax.nxv8i32(<vscale x 8 x i32> splat(i32 1))
   ret i32 %x
@@ -710,8 +701,7 @@ define i32 @smax_poison() {
 
 define i32 @smax_poison_scalable_vector() {
 ; CHECK-LABEL: @smax_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.smax.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.smax.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -735,8 +725,7 @@ define i32 @umin_0() {
 
 define i32 @umin_0_scalable_vector() {
 ; CHECK-LABEL: @umin_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.umin.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.umin.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -752,8 +741,7 @@ define i32 @umin_1() {
 
 define i32 @umin_1_scalable_vector() {
 ; CHECK-LABEL: @umin_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.umin.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 1
 ;
   %x = call i32 @llvm.vector.reduce.umin.nxv8i32(<vscale x 8 x i32> splat (i32 1))
   ret i32 %x
@@ -812,8 +800,7 @@ define i32 @umin_poison() {
 
 define i32 @umin_poison_scalable_vector() {
 ; CHECK-LABEL: @umin_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.umin.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.umin.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x
@@ -837,8 +824,7 @@ define i32 @umax_0() {
 
 define i32 @umax_0_scalable_vector() {
 ; CHECK-LABEL: @umax_0_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.umax.nxv8i32(<vscale x 8 x i32> zeroinitializer)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 0
 ;
   %x = call i32 @llvm.vector.reduce.umax.nxv8i32(<vscale x 8 x i32> zeroinitializer)
   ret i32 %x
@@ -854,8 +840,7 @@ define i32 @umax_1() {
 
 define i32 @umax_1_scalable_vector() {
 ; CHECK-LABEL: @umax_1_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.umax.nxv8i32(<vscale x 8 x i32> splat (i32 1))
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 1
 ;
   %x = call i32 @llvm.vector.reduce.umax.nxv8i32(<vscale x 8 x i32> splat(i32 1))
   ret i32 %x
@@ -914,8 +899,7 @@ define i32 @umax_poison() {
 
 define i32 @umax_poison_scalable_vector() {
 ; CHECK-LABEL: @umax_poison_scalable_vector(
-; CHECK-NEXT:    [[X:%.*]] = call i32 @llvm.vector.reduce.umax.nxv8i32(<vscale x 8 x i32> poison)
-; CHECK-NEXT:    ret i32 [[X]]
+; CHECK-NEXT:    ret i32 poison
 ;
   %x = call i32 @llvm.vector.reduce.umax.nxv8i32(<vscale x 8 x i32> poison)
   ret i32 %x

david-arm · 2025-10-29T07:50:12Z

llvm/lib/Analysis/ConstantFolding.cpp

+  auto *OpVT = cast<VectorType>(Op->getType());

  // This is the same as the underlying binops - poison propagates.
  if (isa<PoisonValue>(Op) || Op->containsPoisonElement())


Interestingly, containsUndefinedElement doesn't try as hard as it could to find poison values in scalable vectors. For example, it could check if there is an insert of poison somewhere.

This is just an observation - no expectation from you to do anything!

However, it looks like the additional call to isa<PoisonValue>(Op) is redundant since containsPoisonElement asks the same question. Since you're here perhaps worth removing?

david-arm · 2025-10-29T08:18:13Z

llvm/lib/Analysis/ConstantFolding.cpp

+      return SplatVal;
+    case Intrinsic::vector_reduce_add:
+    case Intrinsic::vector_reduce_mul:
+      if (SplatVal->isZeroValue())


In theory you can also do a short cut for a mul reduce with a splat value of 1, if you think it's worth adding?

…nxv##(1). Patch also uses isNullValue() rather than isZeroValue(), which is less relevant for integer types.

dtcxzyw

LGTM. Thanks.

llvm-ci · 2025-10-31T11:19:08Z

LLVM Buildbot has detected a new failure on builder lldb-x86_64-debian running on lldb-x86_64-debian while building llvm at step 6 "test".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/162/builds/34282

Here is the relevant piece of the build log for the reference

Step 6 (test) failure: build (failure)
...
PASS: lldb-api :: linux/aarch64/mte_core_file/TestAArch64LinuxMTEMemoryTagCoreFile.py (833 of 3264)
PASS: lldb-shell :: Unwind/split-machine-functions.test (834 of 3264)
PASS: lldb-shell :: Settings/TestFrameFormatFunctionQualifiers.test (835 of 3264)
PASS: lldb-api :: functionalities/signal/handle-abrt/TestHandleAbort.py (836 of 3264)
PASS: lldb-api :: functionalities/target_var/no_vars/TestTargetVarNoVars.py (837 of 3264)
PASS: lldb-shell :: Commands/command-thread-backtrace.test (838 of 3264)
PASS: lldb-api :: functionalities/thread/finish-from-empty-func/TestEmptyFuncThreadStepOut.py (839 of 3264)
PASS: lldb-api :: functionalities/breakpoint/address_breakpoints/TestAddressBreakpoints.py (840 of 3264)
PASS: lldb-api :: functionalities/reverse-execution/TestReverseExecutionNotSupported.py (841 of 3264)
PASS: lldb-api :: commands/process/signal/TestProcessSignal.py (842 of 3264)
FAIL: lldb-api :: tools/lldb-dap/invalidated-event/TestDAP_invalidatedEvent.py (843 of 3264)
******************** TEST 'lldb-api :: tools/lldb-dap/invalidated-event/TestDAP_invalidatedEvent.py' FAILED ********************
Script:
--
/usr/bin/python3 /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/dotest.py -u CXXFLAGS -u CFLAGS --env LLVM_LIBS_DIR=/home/worker/2.0.1/lldb-x86_64-debian/build/./lib --env LLVM_INCLUDE_DIR=/home/worker/2.0.1/lldb-x86_64-debian/build/include --env LLVM_TOOLS_DIR=/home/worker/2.0.1/lldb-x86_64-debian/build/./bin --arch x86_64 --build-dir /home/worker/2.0.1/lldb-x86_64-debian/build/lldb-test-build.noindex --lldb-module-cache-dir /home/worker/2.0.1/lldb-x86_64-debian/build/lldb-test-build.noindex/module-cache-lldb/lldb-api --clang-module-cache-dir /home/worker/2.0.1/lldb-x86_64-debian/build/lldb-test-build.noindex/module-cache-clang/lldb-api --executable /home/worker/2.0.1/lldb-x86_64-debian/build/./bin/lldb --compiler /home/worker/2.0.1/lldb-x86_64-debian/build/./bin/clang --dsymutil /home/worker/2.0.1/lldb-x86_64-debian/build/./bin/dsymutil --make /usr/bin/gmake --llvm-tools-dir /home/worker/2.0.1/lldb-x86_64-debian/build/./bin --lldb-obj-root /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb --lldb-libs-dir /home/worker/2.0.1/lldb-x86_64-debian/build/./lib --cmake-build-type Release -t /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/tools/lldb-dap/invalidated-event -p TestDAP_invalidatedEvent.py
--
Exit Code: 1

Command Output (stdout):
--
lldb version 22.0.0git (https://github.com/llvm/llvm-project.git revision 96c6fd36c1df59d1ba4bb79f22014598882acfcf)
  clang revision 96c6fd36c1df59d1ba4bb79f22014598882acfcf
  llvm revision 96c6fd36c1df59d1ba4bb79f22014598882acfcf
Skipping the following test categories: ['libc++', 'msvcstl', 'dsym', 'gmodules', 'debugserver', 'objc']

--
Command Output (stderr):
--
Change dir to: /home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/tools/lldb-dap/invalidated-event
runCmd: settings clear --all

output: 

runCmd: settings set symbols.enable-external-lookup false

output: 

runCmd: settings set target.inherit-tcc true

output: 

runCmd: settings set target.disable-aslr false

output: 

runCmd: settings set target.detach-on-error false

output:

[LLVM][ConstantFolding] Extend constantFoldVectorReduce to include sc…

3538605

…alable vectors.

paulwalker-arm requested review from MacDue, david-arm and dtcxzyw October 28, 2025 16:57

llvmbot added llvm:instcombine Covers the InstCombine, InstSimplify and AggressiveInstCombine passes llvm:analysis Includes value tracking, cost tables and constant folding llvm:transforms labels Oct 28, 2025

david-arm reviewed Oct 29, 2025

View reviewed changes

Remove unnecessary isa<Posion> check. Add support for vec.reduce.mul.…

4da9437

…nxv##(1). Patch also uses isNullValue() rather than isZeroValue(), which is less relevant for integer types.

dtcxzyw approved these changes Oct 29, 2025

View reviewed changes

paulwalker-arm merged commit 96c6fd3 into llvm:main Oct 31, 2025
10 checks passed

paulwalker-arm deleted the constant-fold-scalable-vector-reductions branch October 31, 2025 11:14

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[LLVM][ConstantFolding] Extend constantFoldVectorReduce to include scalable vectors. #165437

[LLVM][ConstantFolding] Extend constantFoldVectorReduce to include scalable vectors. #165437

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[LLVM][ConstantFolding] Extend constantFoldVectorReduce to include scalable vectors. #165437

[LLVM][ConstantFolding] Extend constantFoldVectorReduce to include scalable vectors. #165437

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llvm-ci commented Oct 31, 2025

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llvmbot commented Oct 28, 2025 •

edited

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