[CIR] Emit allocas into the proper lexical scope (#132468)

Alloca operations were being emitted into the entry block of the current
function unconditionally, even if the variable they represented was
declared in a different scope. This change upstreams the code for
handling
insertion of the alloca into the proper lexcial scope. It also adds a
CIR-to-CIR transformation to hoist allocas to the function entry block,
which is necessary to produce the expected LLVM IR during lowering.

1 files changed, 4 insertions, 2 deletions

diff --git a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
index 4ba3d41..47fc908 100644
--- a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
@@ -138,7 +138,8 @@ mlir::Location CIRGenFunction::getLoc(mlir::Location lhs, mlir::Location rhs) {
 void CIRGenFunction::emitAndUpdateRetAlloca(QualType type, mlir::Location loc,
                                             CharUnits alignment) {
   if (!type->isVoidType()) {
-    fnRetAlloca = emitAlloca("__retval", convertType(type), loc, alignment);
+    fnRetAlloca = emitAlloca("__retval", convertType(type), loc, alignment,
+                             /*insertIntoFnEntryBlock=*/false);
   }
 }
 
@@ -293,7 +294,8 @@ void CIRGenFunction::startFunction(GlobalDecl gd, QualType returnType,
 
     mlir::Value addrVal =
         emitAlloca(cast<NamedDecl>(paramVar)->getName(),
-                   convertType(paramVar->getType()), paramLoc, alignment);
+                   convertType(paramVar->getType()), paramLoc, alignment,
+                   /*insertIntoFnEntryBlock=*/true);
 
     declare(addrVal, paramVar, paramVar->getType(), paramLoc, alignment,
             /*isParam=*/true);