[clang] [CIR] Implement Statement Expressions (PR #153677)

[Andy Kaylor via cfe-commits]

================
@@ -23,16 +25,57 @@ 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(),
-                                 std::string("emitCompoundStmtWithoutScope: ") +
-                                     curStmt->getStmtClassName());
+mlir::LogicalResult CIRGenFunction::emitCompoundStmtWithoutScope(
+    const CompoundStmt &s, Address *lastValue, AggValueSlot slot) {
+  const Stmt *exprResult = s.getStmtExprResult();
+  assert((!lastValue || (lastValue && exprResult)) &&
+         "If lastValue is not null then the CompoundStmt must have a "
+         "StmtExprResult");
+
+  for (Stmt *curStmt : s.body()) {
----------------
andykaylor wrote:

```suggestion
  for (const Stmt *curStmt : s.body()) {
```

https://github.com/llvm/llvm-project/pull/153677