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

[Luke Lau via llvm-commits]

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@@ -454,27 +496,77 @@ bool InterleavedAccessImpl::tryReplaceExtracts(
 }
 
 bool InterleavedAccessImpl::lowerInterleavedStore(
-    StoreInst *SI, SmallSetVector<Instruction *, 32> &DeadInsts) {
-  if (!SI->isSimple())
-    return false;
+    Instruction *Store, SmallSetVector<Instruction *, 32> &DeadInsts) {
+  Value *StoredValue;
+  if (auto *SI = dyn_cast<StoreInst>(Store)) {
+    if (!SI->isSimple())
+      return false;
+    StoredValue = SI->getValueOperand();
+  } else if (auto *VPStore = dyn_cast<VPIntrinsic>(Store)) {
+    assert(VPStore->getIntrinsicID() == Intrinsic::vp_store);
+    // Require a constant mask.
+    if (!isa<ConstantVector>(VPStore->getArgOperand(2)))
+      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();
   // Check if the shufflevector is RE-interleave shuffle.
   unsigned Factor;
   if (!isReInterleaveMask(SVI, Factor, MaxFactor))
     return false;
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lukel97 wrote:

Not for this PR, but just noting that the VP and non-VP paths in this function don't really share much code at all. It's probably justified if you want to split these out into two separate functions. lowerInterleavedLoad might need more refactoring though

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