[llvm] [LV] Support binary and unary operations with EVL-vectorization (PR #93854)

[Shih-Po Hung via llvm-commits]

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@@ -993,6 +997,64 @@ void VPWidenRecipe::execute(VPTransformState &State) {
 #endif
 }
 
+VPWidenEVLRecipe *VPWidenEVLRecipe::create(VPWidenRecipe *W, VPValue &EVL) {
+  auto *R = new VPWidenEVLRecipe(*W->getUnderlyingInstr(), W->operands(), EVL);
+  R->transferFlags(*W);
+  return R;
+}
+
+void VPWidenEVLRecipe::execute(VPTransformState &State) {
+  assert(State.UF == 1 && "Expected only UF == 1 when vectorizing with "
+                          "explicit vector length.");
+  VPValue *Op0 = getOperand(0);
+
+  // If it's scalar operation, hand translation over to VPWidenRecipe
+  if (!State.get(Op0, 0)->getType()->isVectorTy())
+    return VPWidenRecipe::execute(State);
+
+  VPValue *EVL = getEVL();
+  Value *EVLArg = State.get(EVL, 0, /*NeedsScalar=*/true);
+  unsigned Opcode = getOpcode();
+  Instruction *I = getUnderlyingInstr();
+  IRBuilderBase &BuilderIR = State.Builder;
+  VectorBuilder Builder(BuilderIR);
+  Value *Mask = BuilderIR.CreateVectorSplat(State.VF, BuilderIR.getTrue());
+  Value *VPInst = nullptr;
+
+  //===------------------- Binary and Unary Ops ---------------------===//
+  if (Instruction::isBinaryOp(Opcode) || Instruction::isUnaryOp(Opcode)) {
+    // Just widen unops and binops.
+
+    SmallVector<Value *, 4> Ops;
+    for (unsigned I = 0, E = getNumOperands() - 1; I < E; ++I) {
+      VPValue *VPOp = getOperand(I);
+      Ops.push_back(State.get(VPOp, 0));
+    }
+
+    Builder.setMask(Mask).setEVL(EVLArg);
+    VPInst = Builder.createVectorInstruction(Opcode, Ops[0]->getType(), Ops,
+                                             "vp.op");
+
+    if (I)
+      if (auto *VecOp = dyn_cast<Instruction>(VPInst))
+        VecOp->copyIRFlags(I);
+  } else {
+    llvm_unreachable("Unsupported opcode in VPWidenEVLRecipe::execute");
+  }
+  State.set(this, VPInst, 0);
+  State.addMetadata(VPInst, I);
+}
+
+bool VPWidenEVLRecipe::onlyFirstLaneUsed(const VPValue *Op) const {
+  assert(is_contained(operands(), Op) && "Op must be an operand of the recipe");
+  // EVL in that recipe is always the last operand, thus any use before means
+  // the VPValue should be vectorized.
+  for (unsigned I = 0, E = getNumOperands() - 1; I != E; ++I)
+    if (getOperand(I) == Op)
+      return false;
+  return true;
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arcbbb wrote:

can this be simplified to `return getOperand(getNumOperands() - 1) == Op;` ?

https://github.com/llvm/llvm-project/pull/93854