[C++2a] Implement operator<=> CodeGen and ExprConstant
Summary:
This patch tackles long hanging fruit for the builtin operator<=> expressions. It is currently needs some cleanup before landing, but I want to get some initial feedback.
The main changes are:
* Lookup, build, and store the required standard library types and expressions in `ASTContext`. By storing them in ASTContext we don't need to store (and duplicate) the required expressions in the BinaryOperator AST nodes.
* Implement [expr.spaceship] checking, including diagnosing narrowing conversions.
* Implement `ExprConstant` for builtin spaceship operators.
* Implement builitin operator<=> support in `CodeGenAgg`. Initially I emitted the required comparisons using `ScalarExprEmitter::VisitBinaryOperator`, but this caused the operand expressions to be emitted once for every required cmp.
* Implement [builtin.over] with modifications to support the intent of P0946R0. See the note on `BuiltinOperatorOverloadBuilder::addThreeWayArithmeticOverloads` for more information about the workaround.
Reviewers: rsmith, aaron.ballman, majnemer, rnk, compnerd, rjmccall
Reviewed By: rjmccall
Subscribers: rjmccall, rsmith, aaron.ballman, junbuml, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D45476
llvm-svn: 331677
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index bf79e07..a0fc4e7 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -792,7 +792,8 @@
LangOpts.XRayAttrListFiles, SM)),
PrintingPolicy(LOpts), Idents(idents), Selectors(sels),
BuiltinInfo(builtins), DeclarationNames(*this), Comments(SM),
- CommentCommandTraits(BumpAlloc, LOpts.CommentOpts), LastSDM(nullptr, 0) {
+ CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
+ CompCategories(this_()), LastSDM(nullptr, 0) {
TUDecl = TranslationUnitDecl::Create(*this);
}