[clang] [CIR] Add binary operators (PR #132420)

[Andy Kaylor via cfe-commits]

================
@@ -994,6 +992,127 @@ mlir::LogicalResult CIRToLLVMUnaryOpLowering::matchAndRewrite(
                         << elementType;
 }
 
+mlir::LLVM::IntegerOverflowFlags
+CIRToLLVMBinOpLowering::getIntOverflowFlag(cir::BinOp op) const {
+  if (op.getNoUnsignedWrap())
+    return mlir::LLVM::IntegerOverflowFlags::nuw;
+
+  if (op.getNoSignedWrap())
+    return mlir::LLVM::IntegerOverflowFlags::nsw;
+
+  return mlir::LLVM::IntegerOverflowFlags::none;
+}
+
+static bool isIntTypeUnsigned(mlir::Type type) {
+  // TODO: Ideally, we should only need to check cir::IntType here.
+  return mlir::isa<cir::IntType>(type)
+             ? mlir::cast<cir::IntType>(type).isUnsigned()
+             : mlir::cast<mlir::IntegerType>(type).isUnsigned();
+}
+
+mlir::LogicalResult CIRToLLVMBinOpLowering::matchAndRewrite(
+    cir::BinOp op, OpAdaptor adaptor,
+    mlir::ConversionPatternRewriter &rewriter) const {
+  if (adaptor.getLhs().getType() != adaptor.getRhs().getType())
+    return op.emitError() << "inconsistent operands' types not supported yet";
+
+  mlir::Type type = op.getRhs().getType();
+  assert(!cir::MissingFeatures::vectorType());
+  if (!mlir::isa<cir::IntType, cir::BoolType, cir::CIRFPTypeInterface,
+                 mlir::IntegerType>(type))
+    return op.emitError() << "operand type not supported yet";
+
+  auto llvmTy = getTypeConverter()->convertType(op.getType());
+  mlir::Type llvmEltTy =
+      mlir::isa<mlir::VectorType>(llvmTy)
+          ? mlir::cast<mlir::VectorType>(llvmTy).getElementType()
+          : llvmTy;
+  auto rhs = adaptor.getRhs();
+  auto lhs = adaptor.getLhs();
+
+  type = elementTypeIfVector(type);
+
+  switch (op.getKind()) {
+  case cir::BinOpKind::Add:
+    if (mlir::isa<mlir::IntegerType>(llvmEltTy)) {
+      if (op.getSaturated()) {
+        if (isIntTypeUnsigned(type)) {
+          rewriter.replaceOpWithNewOp<mlir::LLVM::UAddSat>(op, lhs, rhs);
+          break;
+        }
+        rewriter.replaceOpWithNewOp<mlir::LLVM::SAddSat>(op, lhs, rhs);
+        break;
+      }
+      rewriter.replaceOpWithNewOp<mlir::LLVM::AddOp>(op, llvmTy, lhs, rhs,
+                                                     getIntOverflowFlag(op));
+    } else
----------------
andykaylor wrote:

The LLVM Coding Standard requires braces on the `else` when they are needed for the `if`. Likewise below.

https://github.com/llvm/llvm-project/pull/132420