Implement CodeGen support for the 'CXXConditionDeclExpr' expression node, which represents a 'condition' declaration, e.g: "if (int x=0) {...}".

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@56045 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGExpr.cpp

@@ -121,6 +121,9 @@ LValue CodeGenFunction::EmitLValue(const Expr *E) {
   case Expr::StringLiteralClass:
     return EmitStringLiteralLValue(cast<StringLiteral>(E));
 
+  case Expr::CXXConditionDeclExprClass:
+    return EmitCXXConditionDeclLValue(cast<CXXConditionDeclExpr>(E));
+
   case Expr::ObjCMessageExprClass:
     return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
   case Expr::ObjCIvarRefExprClass: 
@@ -786,6 +789,12 @@ LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
                           E->getType().getCVRQualifiers());
 }
 
+LValue
+CodeGenFunction::EmitCXXConditionDeclLValue(const CXXConditionDeclExpr *E) {
+  EmitLocalBlockVarDecl(*E->getVarDecl());
+  return EmitDeclRefLValue(E);
+}
+
 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
   // Can only get l-value for message expression returning aggregate type
   RValue RV = EmitObjCMessageExpr(E);

lib/CodeGen/CodeGenFunction.h

@@ -19,6 +19,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/IRBuilder.h"
 #include "clang/AST/Expr.h"
+#include "clang/AST/ExprCXX.h"
 #include "clang/AST/ExprObjC.h"
 
 #include <vector>
@@ -333,6 +334,8 @@ public:
   LValue EmitLValueForField(llvm::Value* Base, FieldDecl* Field,
                             bool isUnion, unsigned CVRQualifiers);
       
+  LValue EmitCXXConditionDeclLValue(const CXXConditionDeclExpr *E);
+
   LValue EmitObjCMessageExprLValue(const ObjCMessageExpr *E);
   LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
   LValue EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E);

test/CodeGen/cxx-condition.cpp

@@ -0,0 +1,9 @@
+// RUN: clang -emit-llvm %s -o %t
+
+void f() {
+  int a;
+  if (int x=a) ++a; else a=x;
+  while (int x=a) ++a;
+  for (; int x=a; --a) ;
+  switch (int x=0) { }
+}