[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/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index 5c0026c..b964cb2 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -137,10 +137,13 @@
ValueWithBytesObjCTypeMethod(nullptr), NSArrayDecl(nullptr),
ArrayWithObjectsMethod(nullptr), NSDictionaryDecl(nullptr),
DictionaryWithObjectsMethod(nullptr), GlobalNewDeleteDeclared(false),
- TUKind(TUKind), NumSFINAEErrors(0), AccessCheckingSFINAE(false),
- InNonInstantiationSFINAEContext(false), NonInstantiationEntries(0),
- ArgumentPackSubstitutionIndex(-1), CurrentInstantiationScope(nullptr),
- DisableTypoCorrection(false), TyposCorrected(0), AnalysisWarnings(*this),
+ TUKind(TUKind), NumSFINAEErrors(0),
+ FullyCheckedComparisonCategories(
+ static_cast<unsigned>(ComparisonCategoryType::Last) + 1),
+ AccessCheckingSFINAE(false), InNonInstantiationSFINAEContext(false),
+ NonInstantiationEntries(0), ArgumentPackSubstitutionIndex(-1),
+ CurrentInstantiationScope(nullptr), DisableTypoCorrection(false),
+ TyposCorrected(0), AnalysisWarnings(*this),
ThreadSafetyDeclCache(nullptr), VarDataSharingAttributesStack(nullptr),
CurScope(nullptr), Ident_super(nullptr), Ident___float128(nullptr) {
TUScope = nullptr;