Get rid of the Range in CXXOperatorCallExpr.

Author: hokein

clang/include/clang/AST/Expr.h

@@ -2905,19 +2905,19 @@ class CallExpr : public Expr {
   //
   // * An optional of type FPOptionsOverride.
   //
-  // CallExpr subclasses are asssumed to be 40 bytes or less, and CallExpr
+  // CallExpr subclasses are asssumed to be 32 bytes or less, and CallExpr
   // itself is 24 bytes. To avoid having to recompute or store the offset of the
-  // trailing objects, we put it at 40 bytes (such that it is suitable for all
+  // trailing objects, we put it at 32 bytes (such that it is suitable for all
   // subclasses) We use the 8 bytes gap left for instances of CallExpr to store
   // the begin source location, which has a significant impact on perf as
   // getBeginLoc is assumed to be cheap.
   // The layourt is as follow:
-  // CallExpr | Begin | 8 bytes left | Trailing Objects
+  // CallExpr | Begin  | Trailing Objects
   // CXXMemberCallExpr | Trailing Objects
   // A bit in CallExprBitfields indicates if source locations are present.
 
 protected:
-  static constexpr unsigned OffsetToTrailingObjects = 40;
+  static constexpr unsigned OffsetToTrailingObjects = 32;
   template <typename T>
   static constexpr unsigned
   sizeToAllocateForCallExprSubclass(unsigned SizeOfTrailingObjects) {

clang/include/clang/AST/ExprCXX.h

@@ -84,7 +84,7 @@ class CXXOperatorCallExpr final : public CallExpr {
   friend class ASTStmtReader;
   friend class ASTStmtWriter;
 
-  SourceRange Range;
+  SourceLocation BeginLoc;
 
   // CXXOperatorCallExpr has some trailing objects belonging
   // to CallExpr. See CallExpr for the details.
@@ -158,9 +158,9 @@ class CXXOperatorCallExpr final : public CallExpr {
                : getOperatorLoc();
   }
 
-  SourceLocation getBeginLoc() const { return Range.getBegin(); }
-  SourceLocation getEndLoc() const { return Range.getEnd(); }
-  SourceRange getSourceRange() const { return Range; }
+  SourceLocation getBeginLoc() const { return BeginLoc; }
+  SourceLocation getEndLoc() const { return getSourceRangeImpl().getEnd(); }
+  SourceRange getSourceRange() const { return getSourceRangeImpl(); }
 
   static bool classof(const Stmt *T) {
     return T->getStmtClass() == CXXOperatorCallExprClass;

clang/lib/AST/Expr.cpp

@@ -1466,8 +1466,8 @@ static unsigned SizeOfCallExprInstance(Expr::StmtClass SC) {
 
 // changing the size of SourceLocation, CallExpr, and
 // subclasses requires careful considerations
-static_assert(sizeof(SourceLocation) == 8 && sizeof(CXXOperatorCallExpr) <= 40,
-              "we assume CXXOperatorCallExpr is at most 40 bytes");
+static_assert(sizeof(SourceLocation) == 8 && sizeof(CXXOperatorCallExpr) <= 32,
+              "we assume CXXOperatorCallExpr is at most 32 bytes");
 
 CallExpr::CallExpr(StmtClass SC, Expr *Fn, ArrayRef<Expr *> PreArgs,
                    ArrayRef<Expr *> Args, QualType Ty, ExprValueKind VK,

clang/lib/AST/ExprCXX.cpp

@@ -600,7 +600,7 @@ CXXOperatorCallExpr::CXXOperatorCallExpr(OverloadedOperatorKind OpKind,
   assert(
       (CXXOperatorCallExprBits.OperatorKind == static_cast<unsigned>(OpKind)) &&
       "OperatorKind overflow!");
-  Range = getSourceRangeImpl();
+  BeginLoc = getSourceRangeImpl().getBegin();
 }
 
 CXXOperatorCallExpr::CXXOperatorCallExpr(unsigned NumArgs, bool HasFPFeatures,

clang/lib/Serialization/ASTReaderStmt.cpp

@@ -1735,7 +1735,7 @@ void ASTStmtReader::VisitMSDependentExistsStmt(MSDependentExistsStmt *S) {
 void ASTStmtReader::VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
   VisitCallExpr(E);
   E->CXXOperatorCallExprBits.OperatorKind = Record.readInt();
-  E->Range = Record.readSourceRange();
+  E->BeginLoc = Record.readSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXRewrittenBinaryOperator(

clang/lib/Serialization/ASTWriterDecl.cpp

@@ -2933,7 +2933,6 @@ void ASTWriter::WriteDeclAbbrevs() {
   // CXXOperatorCallExpr
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Operator Kind
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Source Location
   CXXOperatorCallExprAbbrev = Stream.EmitAbbrev(std::move(Abv));
 
   // Abbreviation for EXPR_CXX_MEMBER_CALL

clang/lib/Serialization/ASTWriterStmt.cpp

@@ -1702,7 +1702,7 @@ void ASTStmtWriter::VisitMSDependentExistsStmt(MSDependentExistsStmt *S) {
 void ASTStmtWriter::VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
   VisitCallExpr(E);
   Record.push_back(E->getOperator());
-  Record.AddSourceRange(E->Range);
+  Record.AddSourceLocation(E->BeginLoc);
 
   if (!E->hasStoredFPFeatures() && !static_cast<bool>(E->getADLCallKind()))
     AbbrevToUse = Writer.getCXXOperatorCallExprAbbrev();