[clang] [CIR][RISCV][NFC] Add CIRGenBuiltinRISCV file to support RISCV builtins codegen (PR #186050)

[Jianjian Guan via cfe-commits]

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@@ -0,0 +1,103 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code to emit RISC-V Builtin calls as CIR or a function call
+// to be later resolved.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CIRGenFunction.h"
+#include "clang/Basic/TargetBuiltins.h"
+
+using namespace clang;
+using namespace clang::CIRGen;
+
+std::optional<mlir::Value>
+CIRGenFunction::emitRISCVBuiltinExpr(unsigned builtinID, const CallExpr *e) {
+  switch (builtinID) {
+  default:
+    return std::nullopt;
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jacquesguan wrote:

Addressed.

https://github.com/llvm/llvm-project/pull/186050