[clang] [CIR] Upstream simple function bodies (PR #127674)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,128 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Emit Stmt nodes as CIR code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CIRGenBuilder.h"
+#include "CIRGenFunction.h"
+
+#include "mlir/IR/Builders.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/Stmt.h"
+
+using namespace clang;
+using namespace clang::CIRGen;
+using namespace cir;
+
+void CIRGenFunction::emitCompoundStmtWithoutScope(const CompoundStmt &s) {
+  for (auto *curStmt : s.body()) {
+    if (emitStmt(curStmt, /*useCurrentScope=*/false).failed())
+      getCIRGenModule().errorNYI(curStmt->getSourceRange(), "statement");
+  }
+}
+
+void CIRGenFunction::emitCompoundStmt(const CompoundStmt &s) {
+  mlir::Location scopeLoc = getLoc(s.getSourceRange());
+  auto scope = builder.create<cir::ScopeOp>(
+      scopeLoc, [&](mlir::OpBuilder &b, mlir::Type &type, mlir::Location loc) {
+        emitCompoundStmtWithoutScope(s);
+      });
+
+  // This code to insert a cir.yield at the end of the scope is temporary until
+  // CIRGenFunction::LexicalScope::cleanup() is upstreamed.
+  if (!scope.getRegion().empty()) {
+    mlir::Block &lastBlock = scope.getRegion().back();
+    if (lastBlock.empty() || !lastBlock.mightHaveTerminator() ||
+        !lastBlock.getTerminator()->hasTrait<mlir::OpTrait::IsTerminator>()) {
+      builder.setInsertionPointToEnd(&lastBlock);
+      builder.create<cir::YieldOp>(getLoc(s.getEndLoc()));
+    }
+  }
+}
+
+// Build CIR for a statement. useCurrentScope should be true if no new scopes
+// need to be created when finding a compound statement.
+mlir::LogicalResult CIRGenFunction::emitStmt(const Stmt *s,
+                                             bool useCurrentScope,
+                                             ArrayRef<const Attr *> attr) {
+  if (mlir::succeeded(emitSimpleStmt(s, useCurrentScope)))
+    return mlir::success();
+
+  // Only a subset of simple statements are supported at the moment.  When more
+  // kinds of statements are supported, a
+  //     switch (s->getStmtClass()) {
+  // will be added here.
+  return mlir::failure();
----------------
andykaylor wrote:

Would `errorNYI()` be useful here?

https://github.com/llvm/llvm-project/pull/127674