merge main into amd-staging (llvm#1067)

Author: ronlieb

clang-tools-extra/clangd/IncludeFixer.cpp

@@ -84,7 +84,6 @@ std::vector<Fix> IncludeFixer::fix(DiagnosticsEngine::Level DiagLevel,
   case diag::err_array_incomplete_or_sizeless_type:
   case diag::err_array_size_incomplete_type:
   case diag::err_asm_incomplete_type:
-  case diag::err_assoc_type_incomplete:
   case diag::err_bad_cast_incomplete:
   case diag::err_call_function_incomplete_return:
   case diag::err_call_incomplete_argument:

clang/docs/ReleaseNotes.rst

@@ -111,6 +111,10 @@ C Language Changes
 
 C2y Feature Support
 ^^^^^^^^^^^^^^^^^^^
+- Implement `WG14 N3409 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3409.pdf>`_
+  which removes UB around use of ``void`` expressions. In practice, this means
+  that ``_Generic`` selection associations may now have ``void`` type, but it
+  also removes UB with code like ``(void)(void)1;``.
 - Implemented `WG14 N3411 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3411.pdf>`_
   which allows a source file to not end with a newline character. This is still
   reported as a conforming extension in earlier language modes.

clang/include/clang/Basic/AttrDocs.td

@@ -1116,10 +1116,10 @@ template instantiation, so the value for ``T::number`` is known.
 def ExtVectorTypeDocs : Documentation {
   let Category = DocCatFunction;
   let Content = [{
-The ext_vector_type(N) attribute specifies that a type is a vector with N
+The ``ext_vector_type(N)`` attribute specifies that a type is a vector with N
 elements, directly mapping to an LLVM vector type. Originally from OpenCL, it
-allows element access the array subscript operator ``[]``, ``sN`` where ``N`` is
-a hexadecimal value, or ``x``, ``y``, ``z``, ``w`` for graphics-style indexing.
+allows element access the array subscript operator ``[]``, ``sN`` where N is
+a hexadecimal value, or ``x, y, z, w`` for graphics-style indexing.
 This attribute enables efficient SIMD operations and is usable in
 general-purpose code.
 
@@ -1128,17 +1128,16 @@ general-purpose code.
   template <typename T, uint32_t N>
   constexpr T simd_reduce(T [[clang::ext_vector_type(N)]] v) {
     static_assert((N & (N - 1)) == 0, "N must be a power of two");
-    if constexpr (N == 1) {
+    if constexpr (N == 1)
       return v[0];
-    } else {
-      T [[clang::ext_vector_type(N / 2)]] reduced = v.hi + v.lo;
-      return simd_reduce(reduced);
-    }
+    else
+      return simd_reduce<T, N / 2>(v.hi + v.lo);
   }
 
 The vector type also supports swizzling up to sixteen elements. This can be done
-using the object accessors. The OpenCL documentation lists the full list of
-accepted values.
+using the object accessors. The OpenCL documentation lists all of the accepted
+values.
+
 .. code-block:: c++
 
   using f16_x16 = _Float16 __attribute__((ext_vector_type(16)));

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -10428,8 +10428,13 @@ def warn_type_safety_null_pointer_required : Warning<
   "specified %0 type tag requires a null pointer">, InGroup<TypeSafety>;
 
 // Generic selections.
-def err_assoc_type_incomplete : Error<
-  "type %0 in generic association incomplete">;
+def ext_assoc_type_incomplete : Extension<
+  "incomplete type %0 in a '_Generic' association is a C2y extension">,
+  InGroup<C2y>;
+def warn_c2y_compat_assoc_type_incomplete : Warning<
+  "use of incomplete type %0 in a '_Generic' association is incompatible with "
+  "C standards before C2y">,
+  InGroup<CPre2yCompat>, DefaultIgnore;
 def err_assoc_type_nonobject : Error<
   "type %0 in generic association not an object type">;
 def err_assoc_type_variably_modified : Error<

clang/include/clang/CIR/Dialect/Builder/CIRBaseBuilder.h

@@ -26,6 +26,10 @@ class CIRBaseBuilderTy : public mlir::OpBuilder {
   CIRBaseBuilderTy(mlir::MLIRContext &mlirContext)
       : mlir::OpBuilder(&mlirContext) {}
 
+  cir::ConstantOp getConstant(mlir::Location loc, mlir::TypedAttr attr) {
+    return create<cir::ConstantOp>(loc, attr.getType(), attr);
+  }
+
   cir::ConstantOp getBool(bool state, mlir::Location loc) {
     return create<cir::ConstantOp>(loc, getBoolTy(), getCIRBoolAttr(state));
   }

clang/include/clang/CIR/Dialect/IR/CIRAttrs.td

@@ -54,6 +54,20 @@ def CIR_BoolAttr : CIR_Attr<"Bool", "bool", [TypedAttrInterface]> {
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// ZeroAttr
+//===----------------------------------------------------------------------===//
+
+def ZeroAttr : CIR_Attr<"Zero", "zero", [TypedAttrInterface]> {
+  let summary = "Attribute to represent zero initialization";
+  let description = [{
+    The ZeroAttr is used to indicate zero initialization on structs.
+  }];
+
+  let parameters = (ins AttributeSelfTypeParameter<"">:$type);
+  let assemblyFormat = [{}];
+}
+
 //===----------------------------------------------------------------------===//
 // UndefAttr
 //===----------------------------------------------------------------------===//

clang/include/clang/CIR/MissingFeatures.h

@@ -41,16 +41,17 @@ struct MissingFeatures {
   static bool supportComdat() { return false; }
 
   // Load/store attributes
-  static bool opLoadThreadLocal() { return false; }
+  static bool opLoadStoreThreadLocal() { return false; }
   static bool opLoadEmitScalarRangeCheck() { return false; }
   static bool opLoadBooleanRepresentation() { return false; }
   static bool opLoadStoreTbaa() { return false; }
   static bool opLoadStoreMemOrder() { return false; }
   static bool opLoadStoreVolatile() { return false; }
   static bool opLoadStoreAlignment() { return false; }
+  static bool opLoadStoreAtomic() { return false; }
+  static bool opLoadStoreObjC() { return false; }
 
   // AllocaOp handling
-  static bool opAllocaVarDeclContext() { return false; }
   static bool opAllocaStaticLocal() { return false; }
   static bool opAllocaNonGC() { return false; }
   static bool opAllocaImpreciseLifetime() { return false; }
@@ -61,6 +62,7 @@ struct MissingFeatures {
   static bool opAllocaReference() { return false; }
   static bool opAllocaAnnotations() { return false; }
   static bool opAllocaDynAllocSize() { return false; }
+  static bool opAllocaCaptureByInit() { return false; }
 
   // FuncOp handling
   static bool opFuncOpenCLKernelMetadata() { return false; }
@@ -76,6 +78,10 @@ struct MissingFeatures {
   static bool constructABIArgDirectExtend() { return false; }
   static bool opGlobalViewAttr() { return false; }
   static bool lowerModeOptLevel() { return false; }
+  static bool opTBAA() { return false; }
+  static bool objCLifetime() { return false; }
+  static bool emitNullabilityCheck() { return false; }
+  static bool astVarDeclInterface() { return false; }
 };
 
 } // namespace cir

clang/include/clang/Driver/Action.h

@@ -76,9 +76,10 @@ class Action {
     LinkerWrapperJobClass,
     StaticLibJobClass,
     BinaryAnalyzeJobClass,
+    BinaryTranslatorJobClass,
 
     JobClassFirst = PreprocessJobClass,
-    JobClassLast = BinaryAnalyzeJobClass
+    JobClassLast = BinaryTranslatorJobClass
   };
 
   // The offloading kind determines if this action is binded to a particular
@@ -687,6 +688,17 @@ class BinaryAnalyzeJobAction : public JobAction {
   }
 };
 
+class BinaryTranslatorJobAction : public JobAction {
+  void anchor() override;
+
+public:
+  BinaryTranslatorJobAction(Action *Input, types::ID Type);
+
+  static bool classof(const Action *A) {
+    return A->getKind() == BinaryTranslatorJobClass;
+  }
+};
+
 } // namespace driver
 } // namespace clang
 

clang/include/clang/Driver/Options.td

@@ -9354,6 +9354,7 @@ def : Option<["/", "-"], "Qembed_debug", KIND_FLAG>, Group<dxc_Group>,
   HelpText<"Embed PDB in shader container (ignored)">;
 def spirv : DXCFlag<"spirv">,
   HelpText<"Generate SPIR-V code">;
+def metal : DXCFlag<"metal">, HelpText<"Generate Metal library">;
 def fspv_target_env_EQ : Joined<["-"], "fspv-target-env=">, Group<dxc_Group>,
   HelpText<"Specify the target environment">,
   Values<"vulkan1.2, vulkan1.3">;

clang/lib/Analysis/UnsafeBufferUsage.cpp

@@ -7,7 +7,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Analysis/Analyses/UnsafeBufferUsage.h"
+#include "clang/AST/APValue.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/AST/Attr.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DynamicRecursiveASTVisitor.h"
 #include "clang/AST/Expr.h"
@@ -353,23 +355,90 @@ isInUnspecifiedUntypedContext(internal::Matcher<Stmt> InnerMatcher) {
   return stmt(anyOf(CompStmt, IfStmtThen, IfStmtElse));
 }
 
+// Returns true iff integer E1 is equivalent to integer E2.
+//
+// For now we only support such expressions:
+//    expr := DRE | const-value | expr BO expr
+//    BO   := '*' | '+'
+//
+// FIXME: We can reuse the expression comparator of the interop analysis after
+// it has been upstreamed.
+static bool areEqualIntegers(const Expr *E1, const Expr *E2, ASTContext &Ctx);
+static bool areEqualIntegralBinaryOperators(const BinaryOperator *E1,
+                                            const Expr *E2_LHS,
+                                            BinaryOperatorKind BOP,
+                                            const Expr *E2_RHS,
+                                            ASTContext &Ctx) {
+  if (E1->getOpcode() == BOP) {
+    switch (BOP) {
+      // Commutative operators:
+    case BO_Mul:
+    case BO_Add:
+      return (areEqualIntegers(E1->getLHS(), E2_LHS, Ctx) &&
+              areEqualIntegers(E1->getRHS(), E2_RHS, Ctx)) ||
+             (areEqualIntegers(E1->getLHS(), E2_RHS, Ctx) &&
+              areEqualIntegers(E1->getRHS(), E2_LHS, Ctx));
+    default:
+      return false;
+    }
+  }
+  return false;
+}
+
+static bool areEqualIntegers(const Expr *E1, const Expr *E2, ASTContext &Ctx) {
+  E1 = E1->IgnoreParenImpCasts();
+  E2 = E2->IgnoreParenImpCasts();
+  if (!E1->getType()->isIntegerType() || E1->getType() != E2->getType())
+    return false;
+
+  Expr::EvalResult ER1, ER2;
+
+  // If both are constants:
+  if (E1->EvaluateAsInt(ER1, Ctx) &&
+      E2->EvaluateAsInt(ER2, Ctx))
+    return ER1.Val.getInt() == ER2.Val.getInt();
+
+  // Otherwise, they should have identical stmt kind:
+  if (E1->getStmtClass() != E2->getStmtClass())
+    return false;
+  switch (E1->getStmtClass()) {
+  case Stmt::DeclRefExprClass:
+    return cast<DeclRefExpr>(E1)->getDecl() == cast<DeclRefExpr>(E2)->getDecl();
+  case Stmt::BinaryOperatorClass: {
+    auto BO2 = cast<BinaryOperator>(E2);
+    return areEqualIntegralBinaryOperators(cast<BinaryOperator>(E1),
+                                           BO2->getLHS(), BO2->getOpcode(),
+                                           BO2->getRHS(), Ctx);
+  }
+  default:
+    return false;
+  }
+}
+
 // Given a two-param std::span construct call, matches iff the call has the
 // following forms:
 //   1. `std::span<T>{new T[n], n}`, where `n` is a literal or a DRE
 //   2. `std::span<T>{new T, 1}`
-//   3. `std::span<T>{&var, 1}`
+//   3. `std::span<T>{&var, 1}` or `std::span<T>{std::addressof(...), 1}`
 //   4. `std::span<T>{a, n}`, where `a` is of an array-of-T with constant size
 //   `n`
 //   5. `std::span<T>{any, 0}`
-//   6. `std::span<T>{std::addressof(...), 1}`
+//   6. `std::span<T>{ (char *)f(args), args[N] * arg*[M]}`, where
+//       `f` is a function with attribute `alloc_size(N, M)`;
+//       `args` represents the list of arguments;
+//       `N, M` are parameter indexes to the allocating element number and size.
+//        Sometimes, there is only one parameter index representing the total
+//        size.
 AST_MATCHER(CXXConstructExpr, isSafeSpanTwoParamConstruct) {
   assert(Node.getNumArgs() == 2 &&
          "expecting a two-parameter std::span constructor");
-  const Expr *Arg0 = Node.getArg(0)->IgnoreImplicit();
-  const Expr *Arg1 = Node.getArg(1)->IgnoreImplicit();
-  auto HaveEqualConstantValues = [&Finder](const Expr *E0, const Expr *E1) {
-    if (auto E0CV = E0->getIntegerConstantExpr(Finder->getASTContext()))
-      if (auto E1CV = E1->getIntegerConstantExpr(Finder->getASTContext())) {
+  const Expr *Arg0 = Node.getArg(0)->IgnoreParenImpCasts();
+  const Expr *Arg1 = Node.getArg(1)->IgnoreParenImpCasts();
+  ASTContext &Ctx = Finder->getASTContext();
+
+  auto HaveEqualConstantValues = [&Ctx](const Expr *E0, const Expr *E1) {
+    if (auto E0CV = E0->getIntegerConstantExpr(Ctx))
+      if (auto E1CV = E1->getIntegerConstantExpr(Ctx)) {
         return APSInt::compareValues(*E0CV, *E1CV) == 0;
       }
     return false;
@@ -381,13 +450,14 @@ AST_MATCHER(CXXConstructExpr, isSafeSpanTwoParamConstruct) {
       }
     return false;
   };
-  std::optional<APSInt> Arg1CV =
-      Arg1->getIntegerConstantExpr(Finder->getASTContext());
+  std::optional<APSInt> Arg1CV = Arg1->getIntegerConstantExpr(Ctx);
 
   if (Arg1CV && Arg1CV->isZero())
     // Check form 5:
     return true;
-  switch (Arg0->IgnoreImplicit()->getStmtClass()) {
+
+  // Check forms 1-3:
+  switch (Arg0->getStmtClass()) {
   case Stmt::CXXNewExprClass:
     if (auto Size = cast<CXXNewExpr>(Arg0)->getArraySize()) {
       // Check form 1:
@@ -407,6 +477,7 @@ AST_MATCHER(CXXConstructExpr, isSafeSpanTwoParamConstruct) {
       return Arg1CV && Arg1CV->isOne();
     break;
   case Stmt::CallExprClass:
+    // Check form 3:
     if (const auto *CE = dyn_cast<CallExpr>(Arg0)) {
       const auto FnDecl = CE->getDirectCallee();
       if (FnDecl && FnDecl->getNameAsString() == "addressof" &&
@@ -421,13 +492,41 @@ AST_MATCHER(CXXConstructExpr, isSafeSpanTwoParamConstruct) {
 
   QualType Arg0Ty = Arg0->IgnoreImplicit()->getType();
 
-  if (auto *ConstArrTy =
-          Finder->getASTContext().getAsConstantArrayType(Arg0Ty)) {
+  if (auto *ConstArrTy = Ctx.getAsConstantArrayType(Arg0Ty)) {
     const APSInt ConstArrSize = APSInt(ConstArrTy->getSize());
 
     // Check form 4:
     return Arg1CV && APSInt::compareValues(ConstArrSize, *Arg1CV) == 0;
   }
+  // Check form 6:
+  if (auto CCast = dyn_cast<CStyleCastExpr>(Arg0)) {
+    if (!CCast->getType()->isPointerType())
+      return false;
+
+    QualType PteTy = CCast->getType()->getPointeeType();
+
+    if (!(PteTy->isConstantSizeType() && Ctx.getTypeSizeInChars(PteTy).isOne()))
+      return false;
+
+    if (const auto *Call = dyn_cast<CallExpr>(CCast->getSubExpr())) {
+      if (const FunctionDecl *FD = Call->getDirectCallee())
+        if (auto *AllocAttr = FD->getAttr<AllocSizeAttr>()) {
+          const Expr *EleSizeExpr =
+              Call->getArg(AllocAttr->getElemSizeParam().getASTIndex());
+          // NumElemIdx is invalid if AllocSizeAttr has 1 argument:
+          ParamIdx NumElemIdx = AllocAttr->getNumElemsParam();
+
+          if (!NumElemIdx.isValid())
+            return areEqualIntegers(Arg1, EleSizeExpr, Ctx);
+
+          const Expr *NumElesExpr = Call->getArg(NumElemIdx.getASTIndex());
+
+          if (auto BO = dyn_cast<BinaryOperator>(Arg1))
+            return areEqualIntegralBinaryOperators(BO, NumElesExpr, BO_Mul,
+                                                   EleSizeExpr, Ctx);
+        }
+    }
+  }
   return false;
 }