[llvm] [IA][RISCV] Support VP loads/stores in InterleavedAccessPass (PR #120490)

[Luke Lau via llvm-commits]

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@@ -630,11 +630,38 @@ getVectorDeinterleaveFactor(IntrinsicInst *II,
   return true;
 }
 
+// Return the corresponded deinterleaved mask, or nullptr if there is no valid
+// mask.
+static Value *getMask(Value *WideMask, unsigned Factor,
+                      VectorType *LeafValueTy) {
+  using namespace llvm::PatternMatch;
+  if (auto *IMI = dyn_cast<IntrinsicInst>(WideMask)) {
+    SmallVector<Value *, 8> Operands;
+    SmallVector<Instruction *, 8> DeadInsts;
+    if (getVectorInterleaveFactor(IMI, Operands, DeadInsts)) {
+      assert(!Operands.empty());
+      if (Operands.size() == Factor && llvm::all_equal(Operands))
+        return Operands[0];
+    }
+  }
+
+  if (match(WideMask, m_AllOnes())) {
+    // Scale the vector length of all-ones mask.
+    ElementCount OrigEC =
+        cast<VectorType>(WideMask->getType())->getElementCount();
+    if (OrigEC.getKnownMinValue() % Factor)
+      return nullptr;
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lukel97 wrote:

Is this an invariant? Can this be made into an assert?

https://github.com/llvm/llvm-project/pull/120490