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

[Kolya Panchenko 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)) {
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nikolaypanchenko wrote:

there's `llvm_unreachable` at 1042. Later I plan to add support for remaining opcodes: FCmp and ICmp here.

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