[llvm] [IR][NFC] Introduce Constant::containsMatchingVectorElement and corresponding matcher m_ContainsMatchingVectorElement (PR #200502)

[Ramkumar Ramachandra via llvm-commits]

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@@ -390,15 +388,16 @@ Instruction *InstCombinerImpl::simplifyMaskedScatter(IntrinsicInst &II) {
   if (!ConstMask)
     return nullptr;
 
-  // If the mask is all zeros or poison, a scatter does nothing.
-  if (match(ConstMask, m_ZeroOrPoison()))
+  // If the mask is all zeros, a scatter does nothing.
+  if (maskIsAllZeroOrUndef(ConstMask))
     return eraseInstFromFunction(II);
 
   // Vector splat address -> scalar store
   if (auto *SplatPtr = getSplatValue(II.getArgOperand(1))) {
     // scatter(splat(value), splat(ptr), non-zero-mask) -> store value, ptr
     if (auto *SplatValue = getSplatValue(II.getArgOperand(0))) {
-      if (maskContainsAllOneOrUndef(ConstMask)) {
+      if (match(ConstMask, m_ContainsMatchingVectorElement(
+                               m_CombineOr(m_AllOnes(), m_UndefValue())))) {
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artagnon wrote:

Just noting: should be able to change this to m_AllOnes() in a follow-up, hopefully with test updates?

https://github.com/llvm/llvm-project/pull/200502