[RISCV][IA] Support masked.load for deinterleaveN matching (#149556)

This builds on the whole series of recent API reworks to implement
support for deinterleaveN of masked.load. The goal is to be able to
enable masked interleave groups in the vectorizer once all the codegen
and costing pieces are in place.

I considered including the shuffle path support in this review as well
(since the RISCV target specific stuff should be common), but decided to
separate it into it's own review just to focus attention on one thing at
a time.

1 files changed, 29 insertions, 13 deletions

diff --git a/llvm/lib/CodeGen/InterleavedAccessPass.cpp b/llvm/lib/CodeGen/InterleavedAccessPass.cpp
index d2b2edf..525ef32 100644
--- a/llvm/lib/CodeGen/InterleavedAccessPass.cpp
+++ b/llvm/lib/CodeGen/InterleavedAccessPass.cpp
@@ -601,31 +601,47 @@ static Value *getMask(Value *WideMask, unsigned Factor,
 bool InterleavedAccessImpl::lowerDeinterleaveIntrinsic(
     IntrinsicInst *DI, SmallSetVector<Instruction *, 32> &DeadInsts) {
   Value *LoadedVal = DI->getOperand(0);
-  if (!LoadedVal->hasOneUse() || !isa<LoadInst, VPIntrinsic>(LoadedVal))
+  if (!LoadedVal->hasOneUse())
+    return false;
+
+  auto *LI = dyn_cast<LoadInst>(LoadedVal);
+  auto *II = dyn_cast<IntrinsicInst>(LoadedVal);
+  if (!LI && !II)
     return false;
 
   const unsigned Factor = getDeinterleaveIntrinsicFactor(DI->getIntrinsicID());
   assert(Factor && "unexpected deinterleave intrinsic");
 
   Value *Mask = nullptr;
-  if (auto *VPLoad = dyn_cast<VPIntrinsic>(LoadedVal)) {
-    if (VPLoad->getIntrinsicID() != Intrinsic::vp_load)
+  if (LI) {
+    if (!LI->isSimple())
       return false;
+
+    LLVM_DEBUG(dbgs() << "IA: Found a load with deinterleave intrinsic " << *DI
+                      << " and factor = " << Factor << "\n");
+  } else {
+    assert(II);
+
     // Check mask operand. Handle both all-true/false and interleaved mask.
-    Value *WideMask = VPLoad->getOperand(1);
-    Mask = getMask(WideMask, Factor, getDeinterleavedVectorType(DI));
-    if (!Mask)
+    Value *WideMask;
+    switch (II->getIntrinsicID()) {
+    default:
       return false;
+    case Intrinsic::vp_load:
+      WideMask = II->getOperand(1);
+      break;
+    case  Intrinsic::masked_load:
+      WideMask = II->getOperand(2);
+      break;
+    }
 
-    LLVM_DEBUG(dbgs() << "IA: Found a vp.load with deinterleave intrinsic "
-                      << *DI << " and factor = " << Factor << "\n");
-  } else {
-    auto *LI = cast<LoadInst>(LoadedVal);
-    if (!LI->isSimple())
+    Mask = getMask(WideMask, Factor, getDeinterleavedVectorType(DI));
+    if (!Mask)
       return false;
 
-    LLVM_DEBUG(dbgs() << "IA: Found a load with deinterleave intrinsic " << *DI
-                      << " and factor = " << Factor << "\n");
+    LLVM_DEBUG(dbgs() << "IA: Found a vp.load or masked.load with deinterleave"
+                      << " intrinsic " << *DI << " and factor = "
+                      << Factor << "\n");
   }
 
   // Try and match this with target specific intrinsics.