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

[Florian Hahn via llvm-commits]

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@@ -1208,6 +1212,43 @@ InstructionCost VPWidenRecipe::computeCost(ElementCount VF,
   }
 }
 
+void VPWidenEVLRecipe::execute(VPTransformState &State) {
+  unsigned Opcode = getOpcode();
+  // TODO: Support other opcodes
+  if (!Instruction::isBinaryOp(Opcode) && !Instruction::isUnaryOp(Opcode))
+    llvm_unreachable("Unsupported opcode in VPWidenEVLRecipe::execute");
+
+  State.setDebugLocFrom(getDebugLoc());
+  assert(State.UF == 1 && "Expected only UF == 1 when vectorizing with "
+                          "explicit vector length.");
+  VPValue *Op0 = getOperand(0);
+
+  assert(State.get(Op0, 0)->getType()->isVectorTy() &&
+         "VPWidenEVLRecipe should not be used for scalars");
+
+  VPValue *EVL = getEVL();
+  Value *EVLArg = State.get(EVL, 0, /*NeedsScalar=*/true);
+  IRBuilderBase &BuilderIR = State.Builder;
+  VectorBuilder Builder(BuilderIR);
+  Value *Mask = BuilderIR.CreateVectorSplat(State.VF, BuilderIR.getTrue());
+
+  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);
+  Value *VPInst =
+      Builder.createVectorInstruction(Opcode, Ops[0]->getType(), Ops, "vp.op");
+  if (isa<FPMathOperator>(VPInst))
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fhahn wrote:

IIUC only FMFs can be set here as other flags are not supported on calls. Would be good to document here

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