[clang] [clang] Remove source range from CXXOperatorCallExpr (PR #147028)

[Haojian Wu via cfe-commits]

https://github.com/hokein created https://github.com/llvm/llvm-project/pull/147028

This patch stops storing a source range in `CXXOperatorCallExpr` and keeps only the begin location.

This change allows us to retain the optimization #141058 when switching to 64-bit source locations.

Performance results:
https://llvm-compile-time-tracker.com/compare.php?from=0588e8188c647460b641b09467fe6b13a8d510d5&to=5958f83476a8b8ba97936f262396d3ff98fb1662&stat=instructions:u



>From 5958f83476a8b8ba97936f262396d3ff98fb1662 Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu at gmail.com>
Date: Fri, 4 Jul 2025 10:40:18 +0200
Subject: [PATCH] [clang] No range in CXXOperatorCallExpr

---
 clang/include/clang/AST/ExprCXX.h         | 8 ++++----
 clang/lib/AST/ExprCXX.cpp                 | 2 +-
 clang/lib/Serialization/ASTReaderStmt.cpp | 2 +-
 clang/lib/Serialization/ASTWriterDecl.cpp | 1 -
 clang/lib/Serialization/ASTWriterStmt.cpp | 2 +-
 5 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/clang/include/clang/AST/ExprCXX.h b/clang/include/clang/AST/ExprCXX.h
index 477373f07f25d..a22c32241ac61 100644
--- a/clang/include/clang/AST/ExprCXX.h
+++ b/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;
diff --git a/clang/lib/AST/ExprCXX.cpp b/clang/lib/AST/ExprCXX.cpp
index 764e20a54dc89..5833a6405125d 100644
--- a/clang/lib/AST/ExprCXX.cpp
+++ b/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,
diff --git a/clang/lib/Serialization/ASTReaderStmt.cpp b/clang/lib/Serialization/ASTReaderStmt.cpp
index 8945407cf666e..0166e493bf03f 100644
--- a/clang/lib/Serialization/ASTReaderStmt.cpp
+++ b/clang/lib/Serialization/ASTReaderStmt.cpp
@@ -1733,7 +1733,7 @@ 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(
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 7f1b39c242e01..5d6f48f651847 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -2934,7 +2934,6 @@ 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
diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index 87536be8c8d98..be9bad9e96cc1 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/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();