[Concepts] Constraint Enforcement & Diagnostics
Part of the C++20 concepts implementation effort.
- Associated constraints (requires clauses, currently) are now enforced when instantiating/specializing templates and when considering partial specializations and function overloads.
- Elaborated diagnostics give helpful insight as to why the constraints were not satisfied.
Phabricator: D41569
Re-commit, after fixing some memory bugs.
diff --git a/clang/lib/AST/ASTConcept.cpp b/clang/lib/AST/ASTConcept.cpp
new file mode 100644
index 0000000..b38b095
--- /dev/null
+++ b/clang/lib/AST/ASTConcept.cpp
@@ -0,0 +1,55 @@
+//===--- ASTConcept.cpp - Concepts Related AST Data Structures --*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file defines AST data structures related to concepts.
+///
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ASTConcept.h"
+#include "clang/AST/ASTContext.h"
+using namespace clang;
+
+ASTConstraintSatisfaction::ASTConstraintSatisfaction(const ASTContext &C,
+ const ConstraintSatisfaction &Satisfaction):
+ NumRecords{Satisfaction.Details.size()},
+ IsSatisfied{Satisfaction.IsSatisfied} {
+ for (unsigned I = 0; I < NumRecords; ++I) {
+ auto &Detail = Satisfaction.Details[I];
+ if (Detail.second.is<Expr *>())
+ new (getTrailingObjects<UnsatisfiedConstraintRecord>() + I)
+ UnsatisfiedConstraintRecord{Detail.first,
+ UnsatisfiedConstraintRecord::second_type(
+ Detail.second.get<Expr *>())};
+ else {
+ auto &SubstitutionDiagnostic =
+ *Detail.second.get<std::pair<SourceLocation, std::string> *>();
+ unsigned MessageSize = SubstitutionDiagnostic.second.size();
+ char *Mem = new (C) char[MessageSize];
+ memcpy(Mem, SubstitutionDiagnostic.second.c_str(), MessageSize);
+ auto *NewSubstDiag = new (C) std::pair<SourceLocation, StringRef>(
+ SubstitutionDiagnostic.first, StringRef(Mem, MessageSize));
+ new (getTrailingObjects<UnsatisfiedConstraintRecord>() + I)
+ UnsatisfiedConstraintRecord{Detail.first,
+ UnsatisfiedConstraintRecord::second_type(
+ NewSubstDiag)};
+ }
+ }
+}
+
+
+ASTConstraintSatisfaction *
+ASTConstraintSatisfaction::Create(const ASTContext &C,
+ const ConstraintSatisfaction &Satisfaction) {
+ std::size_t size =
+ totalSizeToAlloc<UnsatisfiedConstraintRecord>(
+ Satisfaction.Details.size());
+ void *Mem = C.Allocate(size, alignof(ASTConstraintSatisfaction));
+ return new (Mem) ASTConstraintSatisfaction(C, Satisfaction);
+}