[SLP]Check if the copyable element is a sub instruciton with abs in isCommutable

Need to check if the non-copyable element is an instruction before actually
trying to check its NSW attribute.

Author: alexey-bataev

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -537,7 +537,8 @@ static bool isSplat(ArrayRef<Value *> VL) {
 /// \param I The instruction to check for commutativity
 /// \param ValWithUses The value whose uses are analyzed for special
 /// patterns
-static bool isCommutative(Instruction *I, Value *ValWithUses) {
+static bool isCommutative(Instruction *I, Value *ValWithUses,
+                          bool IsCopyable = false) {
   if (auto *Cmp = dyn_cast<CmpInst>(I))
     return Cmp->isCommutative();
   if (auto *BO = dyn_cast<BinaryOperator>(I))
@@ -546,7 +547,7 @@ static bool isCommutative(Instruction *I, Value *ValWithUses) {
             !ValWithUses->hasNUsesOrMore(UsesLimit) &&
             all_of(
                 ValWithUses->uses(),
-                [](const Use &U) {
+                [&](const Use &U) {
                   // Commutative, if icmp eq/ne sub, 0
                   CmpPredicate Pred;
                   if (match(U.getUser(),
@@ -555,10 +556,11 @@ static bool isCommutative(Instruction *I, Value *ValWithUses) {
                     return true;
                   // Commutative, if abs(sub nsw, true) or abs(sub, false).
                   ConstantInt *Flag;
+                  auto *I = dyn_cast<BinaryOperator>(U.get());
                   return match(U.getUser(),
                                m_Intrinsic<Intrinsic::abs>(
                                    m_Specific(U.get()), m_ConstantInt(Flag))) &&
-                         (!cast<Instruction>(U.get())->hasNoSignedWrap() ||
+                         ((!IsCopyable && I && !I->hasNoSignedWrap()) ||
                           Flag->isOne());
                 })) ||
            (BO->getOpcode() == Instruction::FSub &&
@@ -3164,7 +3166,8 @@ class BoUpSLP {
         bool IsInverseOperation = false;
         if (S.isCopyableElement(VL[Lane])) {
           // The value is a copyable element.
-          IsInverseOperation = !isCommutative(MainOp, VL[Lane]);
+          IsInverseOperation =
+              !isCommutative(MainOp, VL[Lane], /*IsCopyable=*/true);
         } else {
           assert(I && "Expected instruction");
           auto [SelectedOp, Ops] = convertTo(I, S);

llvm/test/Transforms/SLPVectorizer/AArch64/non-inst-abs-sub-copyable-value.ll

@@ -0,0 +1,29 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -passes=slp-vectorizer -S -slp-threshold=-100 -mtriple=arm64-apple-macosx15.0.0 < %s | FileCheck %s
+
+define i1 @test(i32 %shr.i.i90, i32 %x) {
+; CHECK-LABEL: define i1 @test(
+; CHECK-SAME: i32 [[SHR_I_I90:%.*]], i32 [[X:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[SUB32_I_I:%.*]] = sub i32 [[X]], 2
+; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <2 x i32> poison, i32 [[SHR_I_I90]], i32 1
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <2 x i32> [[TMP0]], i32 [[SUB32_I_I]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = call <2 x i32> @llvm.abs.v2i32(<2 x i32> [[TMP1]], i1 true)
+; CHECK-NEXT:    [[TMP3:%.*]] = zext <2 x i32> [[TMP2]] to <2 x i64>
+; CHECK-NEXT:    [[TMP4:%.*]] = icmp ugt <2 x i64> [[TMP3]], <i64 100, i64 300>
+; CHECK-NEXT:    [[TMP5:%.*]] = extractelement <2 x i1> [[TMP4]], i32 0
+; CHECK-NEXT:    ret i1 [[TMP5]]
+;
+entry:
+  %cond.i.i = tail call i32 @llvm.abs.i32(i32 %shr.i.i90, i1 true)
+  %conv.i.i91 = zext i32 %cond.i.i to i64
+  %sub32.i.i = sub i32 %x, 2
+  %cond41.i.i = tail call i32 @llvm.abs.i32(i32 %sub32.i.i, i1 true)
+  %conv42.i.i = zext i32 %cond41.i.i to i64
+  %cmp.not.i.2.i.i = icmp ugt i64 %conv.i.i91, 300
+  %cmp.not.i.3.i.i = icmp ugt i64 %conv42.i.i, 100
+  ret i1 %cmp.not.i.3.i.i
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare i32 @llvm.abs.i32(i32, i1 immarg) #0