commit bacf751add8304789a452fc01c78e73771c8d72e
author Bruno Ricci <riccibrun@gmail.com> Tue Oct 30 13:42:41 2018 +0000
committer Bruno Ricci <riccibrun@gmail.com> Tue Oct 30 13:42:41 2018 +0000
tree e1dbb3b2aa4b5416a45a267bae996e753202ac5b
parent af8e036c29ee7ef7cffb55be0d42e578d9d0aa79

[AST] Only store the needed data in WhileStmt

Don't store the data for the condition variable if not needed.
This cuts the size of WhileStmt by up to a pointer.
The order of the children is kept the same.

Differential Revision: https://reviews.llvm.org/D53715

Reviewed By: rjmccall

llvm-svn: 345597

clang/lib/Serialization/ASTReaderStmt.cpp

diff --git a/clang/lib/Serialization/ASTReaderStmt.cpp b/clang/lib/Serialization/ASTReaderStmt.cpp
index 3c63fe1..8865ee3 100644
--- a/clang/lib/Serialization/ASTReaderStmt.cpp
+++ b/clang/lib/Serialization/ASTReaderStmt.cpp
@@ -270,10 +270,14 @@
 
 void ASTStmtReader::VisitWhileStmt(WhileStmt *S) {
   VisitStmt(S);
-  S->setConditionVariable(Record.getContext(), ReadDeclAs<VarDecl>());
+
+  bool HasVar = Record.readInt();
 
   S->setCond(Record.readSubExpr());
   S->setBody(Record.readSubStmt());
+  if (HasVar)
+    S->setConditionVariable(Record.getContext(), ReadDeclAs<VarDecl>());
+
   S->setWhileLoc(ReadSourceLocation());
 }
 
@@ -2325,7 +2329,9 @@
       break;
 
     case STMT_WHILE:
-      S = new (Context) WhileStmt(Empty);
+      S = WhileStmt::CreateEmpty(
+          Context,
+          /* HasVar=*/Record[ASTStmtReader::NumStmtFields + 0]);
       break;
 
     case STMT_DO:

clang/lib/Serialization/ASTWriterStmt.cpp

diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index 396cc1c..3d02971 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/clang/lib/Serialization/ASTWriterStmt.cpp
@@ -183,9 +183,15 @@
 
 void ASTStmtWriter::VisitWhileStmt(WhileStmt *S) {
   VisitStmt(S);
-  Record.AddDeclRef(S->getConditionVariable());
+
+  bool HasVar = S->getConditionVariableDeclStmt() != nullptr;
+  Record.push_back(HasVar);
+
   Record.AddStmt(S->getCond());
   Record.AddStmt(S->getBody());
+  if (HasVar)
+    Record.AddDeclRef(S->getConditionVariable());
+
   Record.AddSourceLocation(S->getWhileLoc());
   Code = serialization::STMT_WHILE;
 }