From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Fri, 3 Jul 2015 15:12:36 +0000 (+0000)
Subject: StmtIterator: Put stmt and decl group pointer into a union.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6baffe87cddc386973a8009486477f2e7f828142;p=clang

StmtIterator: Put stmt and decl group pointer into a union.

Reduce the size of StmtIterator without changing behavior.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@241356 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/AST/StmtIterator.h b/include/clang/AST/StmtIterator.h
index ec7329a4a0..a5a57af523 100644
--- a/include/clang/AST/StmtIterator.h
+++ b/include/clang/AST/StmtIterator.h
@@ -32,8 +32,10 @@ protected:
   enum { StmtMode = 0x0, SizeOfTypeVAMode = 0x1, DeclGroupMode = 0x2,
          Flags = 0x3 };
   
-  Stmt **stmt;
-  Decl **DGI;
+  union {
+    Stmt **stmt;
+    Decl **DGI;
+  };
   uintptr_t RawVAPtr;
   Decl **DGE;
   
@@ -64,10 +66,10 @@ protected:
 
   Stmt*& GetDeclExpr() const;
 
-  StmtIteratorBase(Stmt **s) : stmt(s), DGI(nullptr), RawVAPtr(0) {}
+  StmtIteratorBase(Stmt **s) : stmt(s), RawVAPtr(0) {}
   StmtIteratorBase(const VariableArrayType *t);
   StmtIteratorBase(Decl **dgi, Decl **dge);
-  StmtIteratorBase() : stmt(nullptr), DGI(nullptr), RawVAPtr(0) {}
+  StmtIteratorBase() : stmt(nullptr), RawVAPtr(0) {}
 };
 
 
diff --git a/lib/AST/StmtIterator.cpp b/lib/AST/StmtIterator.cpp
index 1ccba04d9f..732756fbec 100644
--- a/lib/AST/StmtIterator.cpp
+++ b/lib/AST/StmtIterator.cpp
@@ -93,12 +93,12 @@ bool StmtIteratorBase::HandleDecl(Decl* D) {
 }
 
 StmtIteratorBase::StmtIteratorBase(Decl** dgi, Decl** dge)
-  : stmt(nullptr), DGI(dgi), RawVAPtr(DeclGroupMode), DGE(dge) {
+  : DGI(dgi), RawVAPtr(DeclGroupMode), DGE(dge) {
   NextDecl(false);
 }
 
 StmtIteratorBase::StmtIteratorBase(const VariableArrayType* t)
-  : stmt(nullptr), DGI(nullptr), RawVAPtr(SizeOfTypeVAMode) {
+  : DGI(nullptr), RawVAPtr(SizeOfTypeVAMode) {
   RawVAPtr |= reinterpret_cast<uintptr_t>(t);
 }