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

[via llvm-commits]

================
@@ -1140,6 +1144,55 @@ void VPWidenRecipe::execute(VPTransformState &State) {
 #endif
 }
 
+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
+  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);
+  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);
----------------
LiqinWeng wrote:

 ```
for (VPValue *VPOp : operands()) {
      bool IsScalar = VPOp == EVL;
      Ops.push_back(State.get(VPOp, 0, IsScalar));
 }
```

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