[llvm] [IA][RISCV] Add support for vp.load/vp.store with shufflevector (PR #135445)

[Alexey Bataev via llvm-commits]

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@@ -454,27 +522,79 @@ bool InterleavedAccessImpl::tryReplaceExtracts(
 }
 
 bool InterleavedAccessImpl::lowerInterleavedStore(
-    StoreInst *SI, SmallSetVector<Instruction *, 32> &DeadInsts) {
-  if (!SI->isSimple())
-    return false;
+    Instruction *StoreOp, SmallSetVector<Instruction *, 32> &DeadInsts) {
+  Value *StoredValue;
+  if (auto *SI = dyn_cast<StoreInst>(StoreOp)) {
+    if (!SI->isSimple())
+      return false;
+    StoredValue = SI->getValueOperand();
+  } else if (auto *VPStore = dyn_cast<VPIntrinsic>(StoreOp)) {
+    assert(VPStore->getIntrinsicID() == Intrinsic::vp_store);
+    // Require a constant mask and evl.
+    if (!isa<ConstantVector>(VPStore->getArgOperand(2)) ||
+        !isa<ConstantInt>(VPStore->getArgOperand(3)))
+      return false;
+    StoredValue = VPStore->getArgOperand(0);
+  } else {
+    llvm_unreachable("unsupported store operation");
+  }
 
-  auto *SVI = dyn_cast<ShuffleVectorInst>(SI->getValueOperand());
+  auto *SVI = dyn_cast<ShuffleVectorInst>(StoredValue);
   if (!SVI || !SVI->hasOneUse() || isa<ScalableVectorType>(SVI->getType()))
     return false;
 
+  unsigned NumStoredElements =
+      cast<FixedVectorType>(SVI->getType())->getNumElements();
+  // If this is a vp.store, record its mask (NOT shuffle mask).
+  BitVector MaskedIndices(NumStoredElements);
+  if (auto *VPStore = dyn_cast<VPIntrinsic>(StoreOp)) {
+    auto *Mask = cast<ConstantVector>(VPStore->getArgOperand(2));
+    assert(cast<FixedVectorType>(Mask->getType())->getNumElements() ==
+           NumStoredElements);
+    if (auto *Splat = Mask->getSplatValue()) {
+      // All-zeros mask, bail out early.
+      if (Splat->isZeroValue())
+        return false;
+    } else {
+      for (unsigned i = 0U; i < NumStoredElements; ++i) {
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alexey-bataev wrote:

`for (unsigned I : seq<unsigned>(NumStoredElements)) {`

https://github.com/llvm/llvm-project/pull/135445