[TableGen][InstrInfoEmitter] Count sub-operands on def operands

clang/docs/ReleaseNotes.rst

@@ -203,6 +203,12 @@ Non-comprehensive list of changes in this release
 - ``__typeof_unqual__`` is available in all C modes as an extension, which behaves
   like ``typeof_unqual`` from C23, similar to ``__typeof__`` and ``typeof``.
 
+- Improved stack usage with C++ initialization code. This allows significantly
+  more levels of recursive initialization before reaching stack exhaustion
+  limits. This will positively impact recursive template instantiation code,
+  but should also reduce memory overhead for initializations in general.
+  Fixes #GH88330
+
 New Compiler Flags
 ------------------
 - ``-fsanitize=implicit-bitfield-conversion`` checks implicit truncation and
@@ -417,6 +423,8 @@ Bug Fixes in This Version
 - Fixed a regression in CTAD that a friend declaration that befriends itself may cause
   incorrect constraint substitution. (#GH86769).
 
+- Fixed an assertion failure on invalid InitListExpr in C89 mode (#GH88008).
+
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

clang/docs/tools/clang-formatted-files.txt

@@ -123,6 +123,7 @@ clang/include/clang/Analysis/Analyses/CalledOnceCheck.h
 clang/include/clang/Analysis/Analyses/CFGReachabilityAnalysis.h
 clang/include/clang/Analysis/Analyses/ExprMutationAnalyzer.h
 clang/include/clang/Analysis/FlowSensitive/AdornedCFG.h
+clang/include/clang/Analysis/FlowSensitive/ASTOps.h
 clang/include/clang/Analysis/FlowSensitive/DataflowAnalysis.h
 clang/include/clang/Analysis/FlowSensitive/DataflowAnalysisContext.h
 clang/include/clang/Analysis/FlowSensitive/DataflowEnvironment.h
@@ -307,6 +308,7 @@ clang/lib/Analysis/CalledOnceCheck.cpp
 clang/lib/Analysis/CloneDetection.cpp
 clang/lib/Analysis/CodeInjector.cpp
 clang/lib/Analysis/FlowSensitive/AdornedCFG.cpp
+clang/lib/Analysis/FlowSensitive/ASTOps.cpp
 clang/lib/Analysis/FlowSensitive/DataflowAnalysisContext.cpp
 clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
 clang/lib/Analysis/FlowSensitive/DebugSupport.cpp

clang/include/clang/Analysis/FlowSensitive/ASTOps.h

@@ -0,0 +1,98 @@
+//===-- ASTOps.h -------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//  Operations on AST nodes that are used in flow-sensitive analysis.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_ASTOPS_H
+#define LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_ASTOPS_H
+
+#include "clang/AST/Decl.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/Type.h"
+#include "clang/Analysis/FlowSensitive/StorageLocation.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/SetVector.h"
+
+namespace clang {
+namespace dataflow {
+
+/// Skip past nodes that the CFG does not emit. These nodes are invisible to
+/// flow-sensitive analysis, and should be ignored as they will effectively not
+/// exist.
+///
+///   * `ParenExpr` - The CFG takes the operator precedence into account, but
+///   otherwise omits the node afterwards.
+///
+///   * `ExprWithCleanups` - The CFG will generate the appropriate calls to
+///   destructors and then omit the node.
+///
+const Expr &ignoreCFGOmittedNodes(const Expr &E);
+const Stmt &ignoreCFGOmittedNodes(const Stmt &S);
+
+/// A set of `FieldDecl *`. Use `SmallSetVector` to guarantee deterministic
+/// iteration order.
+using FieldSet = llvm::SmallSetVector<const FieldDecl *, 4>;
+
+/// Returns the set of all fields in the type.
+FieldSet getObjectFields(QualType Type);
+
+/// Returns whether `Fields` and `FieldLocs` contain the same fields.
+bool containsSameFields(const FieldSet &Fields,
+                        const RecordStorageLocation::FieldToLoc &FieldLocs);
+
+/// Helper class for initialization of a record with an `InitListExpr`.
+/// `InitListExpr::inits()` contains the initializers for both the base classes
+/// and the fields of the record; this helper class separates these out into two
+/// different lists. In addition, it deals with special cases associated with
+/// unions.
+class RecordInitListHelper {
+public:
+  // `InitList` must have record type.
+  RecordInitListHelper(const InitListExpr *InitList);
+
+  // Base classes with their associated initializer expressions.
+  ArrayRef<std::pair<const CXXBaseSpecifier *, Expr *>> base_inits() const {
+    return BaseInits;
+  }
+
+  // Fields with their associated initializer expressions.
+  ArrayRef<std::pair<const FieldDecl *, Expr *>> field_inits() const {
+    return FieldInits;
+  }
+
+private:
+  SmallVector<std::pair<const CXXBaseSpecifier *, Expr *>> BaseInits;
+  SmallVector<std::pair<const FieldDecl *, Expr *>> FieldInits;
+
+  // We potentially synthesize an `ImplicitValueInitExpr` for unions. It's a
+  // member variable because we store a pointer to it in `FieldInits`.
+  std::optional<ImplicitValueInitExpr> ImplicitValueInitForUnion;
+};
+
+/// A collection of several types of declarations, all referenced from the same
+/// function.
+struct ReferencedDecls {
+  /// Non-static member variables.
+  FieldSet Fields;
+  /// All variables with static storage duration, notably including static
+  /// member variables and static variables declared within a function.
+  llvm::DenseSet<const VarDecl *> Globals;
+  /// Free functions and member functions which are referenced (but not
+  /// necessarily called).
+  llvm::DenseSet<const FunctionDecl *> Functions;
+};
+
+/// Returns declarations that are declared in or referenced from `FD`.
+ReferencedDecls getReferencedDecls(const FunctionDecl &FD);
+
+} // namespace dataflow
+} // namespace clang
+
+#endif // LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_ASTOPS_H

clang/include/clang/Analysis/FlowSensitive/DataflowAnalysisContext.h

@@ -18,6 +18,7 @@
 #include "clang/AST/Decl.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/TypeOrdering.h"
+#include "clang/Analysis/FlowSensitive/ASTOps.h"
 #include "clang/Analysis/FlowSensitive/AdornedCFG.h"
 #include "clang/Analysis/FlowSensitive/Arena.h"
 #include "clang/Analysis/FlowSensitive/Solver.h"
@@ -30,38 +31,11 @@
 #include <cassert>
 #include <memory>
 #include <optional>
-#include <type_traits>
-#include <utility>
-#include <vector>
 
 namespace clang {
 namespace dataflow {
 class Logger;
 
-/// Skip past nodes that the CFG does not emit. These nodes are invisible to
-/// flow-sensitive analysis, and should be ignored as they will effectively not
-/// exist.
-///
-///   * `ParenExpr` - The CFG takes the operator precedence into account, but
-///   otherwise omits the node afterwards.
-///
-///   * `ExprWithCleanups` - The CFG will generate the appropriate calls to
-///   destructors and then omit the node.
-///
-const Expr &ignoreCFGOmittedNodes(const Expr &E);
-const Stmt &ignoreCFGOmittedNodes(const Stmt &S);
-
-/// A set of `FieldDecl *`. Use `SmallSetVector` to guarantee deterministic
-/// iteration order.
-using FieldSet = llvm::SmallSetVector<const FieldDecl *, 4>;
-
-/// Returns the set of all fields in the type.
-FieldSet getObjectFields(QualType Type);
-
-/// Returns whether `Fields` and `FieldLocs` contain the same fields.
-bool containsSameFields(const FieldSet &Fields,
-                        const RecordStorageLocation::FieldToLoc &FieldLocs);
-
 struct ContextSensitiveOptions {
   /// The maximum depth to analyze. A value of zero is equivalent to disabling
   /// context-sensitive analysis entirely.

clang/include/clang/Analysis/FlowSensitive/DataflowEnvironment.h

@@ -775,42 +775,6 @@ RecordStorageLocation *getImplicitObjectLocation(const CXXMemberCallExpr &MCE,
 RecordStorageLocation *getBaseObjectLocation(const MemberExpr &ME,
                                              const Environment &Env);
 
-/// Returns the fields of a `RecordDecl` that are initialized by an
-/// `InitListExpr`, in the order in which they appear in
-/// `InitListExpr::inits()`.
-/// `Init->getType()` must be a record type.
-std::vector<const FieldDecl *>
-getFieldsForInitListExpr(const InitListExpr *InitList);
-
-/// Helper class for initialization of a record with an `InitListExpr`.
-/// `InitListExpr::inits()` contains the initializers for both the base classes
-/// and the fields of the record; this helper class separates these out into two
-/// different lists. In addition, it deals with special cases associated with
-/// unions.
-class RecordInitListHelper {
-public:
-  // `InitList` must have record type.
-  RecordInitListHelper(const InitListExpr *InitList);
-
-  // Base classes with their associated initializer expressions.
-  ArrayRef<std::pair<const CXXBaseSpecifier *, Expr *>> base_inits() const {
-    return BaseInits;
-  }
-
-  // Fields with their associated initializer expressions.
-  ArrayRef<std::pair<const FieldDecl *, Expr *>> field_inits() const {
-    return FieldInits;
-  }
-
-private:
-  SmallVector<std::pair<const CXXBaseSpecifier *, Expr *>> BaseInits;
-  SmallVector<std::pair<const FieldDecl *, Expr *>> FieldInits;
-
-  // We potentially synthesize an `ImplicitValueInitExpr` for unions. It's a
-  // member variable because we store a pointer to it in `FieldInits`.
-  std::optional<ImplicitValueInitExpr> ImplicitValueInitForUnion;
-};
-
 /// Associates a new `RecordValue` with `Loc` and returns the new value.
 RecordValue &refreshRecordValue(RecordStorageLocation &Loc, Environment &Env);
 

clang/include/clang/Sema/Initialization.h

@@ -1134,7 +1134,7 @@ class InitializationSequence {
   OverloadingResult FailedOverloadResult;
 
   /// The candidate set created when initialization failed.
-  OverloadCandidateSet FailedCandidateSet;
+  std::unique_ptr<OverloadCandidateSet> FailedCandidateSet;
 
   /// The incomplete type that caused a failure.
   QualType FailedIncompleteType;
@@ -1403,7 +1403,9 @@ class InitializationSequence {
   /// Retrieve a reference to the candidate set when overload
   /// resolution fails.
   OverloadCandidateSet &getFailedCandidateSet() {
-    return FailedCandidateSet;
+    assert(FailedCandidateSet &&
+           "this should have been allocated in the constructor!");
+    return *FailedCandidateSet;
   }
 
   /// Get the overloading result, for when the initialization

clang/include/clang/Sema/Overload.h

@@ -37,6 +37,7 @@
 #include <cassert>
 #include <cstddef>
 #include <cstdint>
+#include <memory>
 #include <utility>
 
 namespace clang {
@@ -874,7 +875,8 @@ class Sema;
     ConversionFixItGenerator Fix;
 
     /// Viable - True to indicate that this overload candidate is viable.
-    bool Viable : 1;
+    LLVM_PREFERRED_TYPE(bool)
+    unsigned Viable : 1;
 
     /// Whether this candidate is the best viable function, or tied for being
     /// the best viable function.
@@ -883,12 +885,14 @@ class Sema;
     /// was part of the ambiguity kernel: the minimal non-empty set of viable
     /// candidates such that all elements of the ambiguity kernel are better
     /// than all viable candidates not in the ambiguity kernel.
-    bool Best : 1;
+    LLVM_PREFERRED_TYPE(bool)
+    unsigned Best : 1;
 
     /// IsSurrogate - True to indicate that this candidate is a
     /// surrogate for a conversion to a function pointer or reference
     /// (C++ [over.call.object]).
-    bool IsSurrogate : 1;
+    LLVM_PREFERRED_TYPE(bool)
+    unsigned IsSurrogate : 1;
 
     /// IgnoreObjectArgument - True to indicate that the first
     /// argument's conversion, which for this function represents the
@@ -897,18 +901,20 @@ class Sema;
     /// implicit object argument is just a placeholder) or a
     /// non-static member function when the call doesn't have an
     /// object argument.
-    bool IgnoreObjectArgument : 1;
+    LLVM_PREFERRED_TYPE(bool)
+    unsigned IgnoreObjectArgument : 1;
 
     /// True if the candidate was found using ADL.
-    CallExpr::ADLCallKind IsADLCandidate : 1;
+    LLVM_PREFERRED_TYPE(CallExpr::ADLCallKind)
+    unsigned IsADLCandidate : 1;
 
     /// Whether this is a rewritten candidate, and if so, of what kind?
     LLVM_PREFERRED_TYPE(OverloadCandidateRewriteKind)
     unsigned RewriteKind : 2;
 
     /// FailureKind - The reason why this candidate is not viable.
-    /// Actually an OverloadFailureKind.
-    unsigned char FailureKind;
+    LLVM_PREFERRED_TYPE(OverloadFailureKind)
+    unsigned FailureKind : 5;
 
     /// The number of call arguments that were explicitly provided,
     /// to be used while performing partial ordering of function templates.
@@ -972,7 +978,9 @@ class Sema;
   private:
     friend class OverloadCandidateSet;
     OverloadCandidate()
-        : IsSurrogate(false), IsADLCandidate(CallExpr::NotADL), RewriteKind(CRK_None) {}
+        : IsSurrogate(false),
+          IsADLCandidate(static_cast<unsigned>(CallExpr::NotADL)),
+          RewriteKind(CRK_None) {}
   };
 
   /// OverloadCandidateSet - A set of overload candidates, used in C++
@@ -1070,51 +1078,16 @@ class Sema;
     };
 
   private:
-    SmallVector<OverloadCandidate, 16> Candidates;
-    llvm::SmallPtrSet<uintptr_t, 16> Functions;
-
-    // Allocator for ConversionSequenceLists. We store the first few of these
-    // inline to avoid allocation for small sets.
-    llvm::BumpPtrAllocator SlabAllocator;
+    SmallVector<OverloadCandidate, 4> Candidates;
+    llvm::SmallPtrSet<uintptr_t, 4> Functions;
 
     SourceLocation Loc;
     CandidateSetKind Kind;
     OperatorRewriteInfo RewriteInfo;
 
-    constexpr static unsigned NumInlineBytes =
-        24 * sizeof(ImplicitConversionSequence);
-    unsigned NumInlineBytesUsed = 0;
-    alignas(void *) char InlineSpace[NumInlineBytes];
-
     // Address space of the object being constructed.
     LangAS DestAS = LangAS::Default;
 
-    /// If we have space, allocates from inline storage. Otherwise, allocates
-    /// from the slab allocator.
-    /// FIXME: It would probably be nice to have a SmallBumpPtrAllocator
-    /// instead.
-    /// FIXME: Now that this only allocates ImplicitConversionSequences, do we
-    /// want to un-generalize this?
-    template <typename T>
-    T *slabAllocate(unsigned N) {
-      // It's simpler if this doesn't need to consider alignment.
-      static_assert(alignof(T) == alignof(void *),
-                    "Only works for pointer-aligned types.");
-      static_assert(std::is_trivial<T>::value ||
-                        std::is_same<ImplicitConversionSequence, T>::value,
-                    "Add destruction logic to OverloadCandidateSet::clear().");
-
-      unsigned NBytes = sizeof(T) * N;
-      if (NBytes > NumInlineBytes - NumInlineBytesUsed)
-        return SlabAllocator.Allocate<T>(N);
-      char *FreeSpaceStart = InlineSpace + NumInlineBytesUsed;
-      assert(uintptr_t(FreeSpaceStart) % alignof(void *) == 0 &&
-             "Misaligned storage!");
-
-      NumInlineBytesUsed += NBytes;
-      return reinterpret_cast<T *>(FreeSpaceStart);
-    }
-
     void destroyCandidates();
 
   public:
@@ -1163,12 +1136,7 @@ class Sema;
     ConversionSequenceList
     allocateConversionSequences(unsigned NumConversions) {
       ImplicitConversionSequence *Conversions =
-          slabAllocate<ImplicitConversionSequence>(NumConversions);
-
-      // Construct the new objects.
-      for (unsigned I = 0; I != NumConversions; ++I)
-        new (&Conversions[I]) ImplicitConversionSequence();
-
+          new ImplicitConversionSequence[NumConversions];
       return ConversionSequenceList(Conversions, NumConversions);
     }