Merge from 'main' to 'sycl-web' (#5)

Also removed the workaround for D99173, and updated vc-intrinsics to use
a version with the fix it.

  CONFLICT (content): Merge conflict in clang/lib/CodeGen/CodeGenFunction.cpp

clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.cpp

@@ -12,6 +12,7 @@
 #include "../utils/LexerUtils.h"
 #include "../utils/Matchers.h"
 #include "../utils/OptionsUtils.h"
+#include "clang/AST/Decl.h"
 #include "clang/Basic/Diagnostic.h"
 
 namespace clang {
@@ -72,14 +73,14 @@ AST_MATCHER_FUNCTION(StatementMatcher, isConstRefReturningFunctionCall) {
       .bind(InitFunctionCallId);
 }
 
-AST_MATCHER_FUNCTION(StatementMatcher, isInitializedFromReferenceToConst) {
+AST_MATCHER_FUNCTION(StatementMatcher, initializerReturnsReferenceToConst) {
   auto OldVarDeclRef =
       declRefExpr(to(varDecl(hasLocalStorage()).bind(OldVarDeclId)));
-  return declStmt(has(varDecl(hasInitializer(
+  return expr(
       anyOf(isConstRefReturningFunctionCall(), isConstRefReturningMethodCall(),
             ignoringImpCasts(OldVarDeclRef),
-            ignoringImpCasts(unaryOperator(
-                hasOperatorName("&"), hasUnaryOperand(OldVarDeclRef))))))));
+            ignoringImpCasts(unaryOperator(hasOperatorName("&"),
+                                           hasUnaryOperand(OldVarDeclRef)))));
 }
 
 // This checks that the variable itself is only used as const, and also makes
@@ -106,18 +107,14 @@ static bool isInitializingVariableImmutable(const VarDecl &InitializingVar,
   if (!isa<ReferenceType, PointerType>(T))
     return true;
 
-  auto Matches =
-      match(findAll(declStmt(has(varDecl(equalsNode(&InitializingVar))))
-                        .bind("declStmt")),
-            BlockStmt, Context);
-  // The reference or pointer is not initialized in the BlockStmt. We assume
-  // its pointee is not modified then.
-  if (Matches.empty())
+  // The reference or pointer is not declared and hence not initialized anywhere
+  // in the function. We assume its pointee is not modified then.
+  if (!InitializingVar.isLocalVarDecl() || !InitializingVar.hasInit()) {
     return true;
+  }
 
-  const auto *Initialization = selectFirst<DeclStmt>("declStmt", Matches);
-  Matches =
-      match(isInitializedFromReferenceToConst(), *Initialization, Context);
+  auto Matches = match(initializerReturnsReferenceToConst(),
+                       *InitializingVar.getInit(), Context);
   // The reference is initialized from a free function without arguments
   // returning a const reference. This is a global immutable object.
   if (selectFirst<CallExpr>(InitFunctionCallId, Matches) != nullptr)

clang-tools-extra/clang-tidy/performance/UnnecessaryCopyInitialization.h

@@ -10,6 +10,7 @@
 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_UNNECESSARY_COPY_INITIALIZATION_H
 
 #include "../ClangTidyCheck.h"
+#include "clang/AST/Decl.h"
 
 namespace clang {
 namespace tidy {

clang-tools-extra/clangd/CompileCommands.cpp

@@ -20,6 +20,8 @@
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Program.h"
+#include <string>
+#include <vector>
 
 namespace clang {
 namespace clangd {
@@ -209,14 +211,20 @@ void CommandMangler::adjust(std::vector<std::string> &Cmd) const {
   Cmd = tooling::getStripPluginsAdjuster()(Cmd, "");
   Cmd = tooling::getClangSyntaxOnlyAdjuster()(Cmd, "");
 
+  std::vector<std::string> ToAppend;
   if (ResourceDir && !Has("-resource-dir"))
-    Cmd.push_back(("-resource-dir=" + *ResourceDir));
+    ToAppend.push_back(("-resource-dir=" + *ResourceDir));
 
   // Don't set `-isysroot` if it is already set or if `--sysroot` is set.
   // `--sysroot` is a superset of the `-isysroot` argument.
   if (Sysroot && !Has("-isysroot") && !Has("--sysroot")) {
-    Cmd.push_back("-isysroot");
-    Cmd.push_back(*Sysroot);
+    ToAppend.push_back("-isysroot");
+    ToAppend.push_back(*Sysroot);
+  }
+
+  if (!ToAppend.empty()) {
+    Cmd = tooling::getInsertArgumentAdjuster(
+        std::move(ToAppend), tooling::ArgumentInsertPosition::END)(Cmd, "");
   }
 
   if (!Cmd.empty()) {
@@ -504,7 +512,6 @@ void ArgStripper::process(std::vector<std::string> &Args) const {
   Args.resize(Write);
 }
 
-
 std::string printArgv(llvm::ArrayRef<llvm::StringRef> Args) {
   std::string Buf;
   llvm::raw_string_ostream OS(Buf);

clang-tools-extra/clangd/ConfigCompile.cpp

@@ -47,6 +47,7 @@
 #include "llvm/Support/Regex.h"
 #include "llvm/Support/SMLoc.h"
 #include "llvm/Support/SourceMgr.h"
+#include <algorithm>
 #include <string>
 
 namespace clang {
@@ -270,7 +271,9 @@ struct FragmentCompiler {
         Add.push_back(std::move(*A));
       Out.Apply.push_back([Add(std::move(Add))](const Params &, Config &C) {
         C.CompileFlags.Edits.push_back([Add](std::vector<std::string> &Args) {
-          Args.insert(Args.end(), Add.begin(), Add.end());
+          // The point to insert at. Just append when `--` isn't present.
+          auto It = llvm::find(Args, "--");
+          Args.insert(It, Add.begin(), Add.end());
         });
       });
     }

clang-tools-extra/clangd/Diagnostics.cpp

@@ -76,10 +76,10 @@ bool mentionsMainFile(const Diag &D) {
   return false;
 }
 
-bool isExcluded(const Diag &D) {
+bool isExcluded(unsigned DiagID) {
   // clang will always fail parsing MS ASM, we don't link in desc + asm parser.
-  if (D.ID == clang::diag::err_msasm_unable_to_create_target ||
-      D.ID == clang::diag::err_msasm_unsupported_arch)
+  if (DiagID == clang::diag::err_msasm_unable_to_create_target ||
+      DiagID == clang::diag::err_msasm_unsupported_arch)
     return true;
   return false;
 }
@@ -726,44 +726,42 @@ void StoreDiags::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
     // Handle the new main diagnostic.
     flushLastDiag();
 
-    if (Adjuster) {
+    LastDiag = Diag();
+    // FIXME: Merge with feature modules.
+    if (Adjuster)
       DiagLevel = Adjuster(DiagLevel, Info);
-      if (DiagLevel == DiagnosticsEngine::Ignored) {
-        LastPrimaryDiagnosticWasSuppressed = true;
-        return;
-      }
-    }
-    LastPrimaryDiagnosticWasSuppressed = false;
 
-    LastDiag = Diag();
     FillDiagBase(*LastDiag);
+    if (isExcluded(LastDiag->ID))
+      LastDiag->Severity = DiagnosticsEngine::Ignored;
+    if (DiagCB)
+      DiagCB(Info, *LastDiag);
+    // Don't bother filling in the rest if diag is going to be dropped.
+    if (LastDiag->Severity == DiagnosticsEngine::Ignored)
+      return;
+
     LastDiagLoc.emplace(Info.getLocation(), Info.getSourceManager());
     LastDiagOriginallyError = OriginallyError;
-
     if (!Info.getFixItHints().empty())
       AddFix(true /* try to invent a message instead of repeating the diag */);
     if (Fixer) {
-      auto ExtraFixes = Fixer(DiagLevel, Info);
+      auto ExtraFixes = Fixer(LastDiag->Severity, Info);
       LastDiag->Fixes.insert(LastDiag->Fixes.end(), ExtraFixes.begin(),
                              ExtraFixes.end());
     }
-    if (DiagCB)
-      DiagCB(Info, *LastDiag);
   } else {
     // Handle a note to an existing diagnostic.
-
-    // If a diagnostic was suppressed due to the suppression filter,
-    // also suppress notes associated with it.
-    if (LastPrimaryDiagnosticWasSuppressed) {
-      return;
-    }
-
     if (!LastDiag) {
       assert(false && "Adding a note without main diagnostic");
       IgnoreDiagnostics::log(DiagLevel, Info);
       return;
     }
 
+    // If a diagnostic was suppressed due to the suppression filter,
+    // also suppress notes associated with it.
+    if (LastDiag->Severity == DiagnosticsEngine::Ignored)
+      return;
+
     if (!Info.getFixItHints().empty()) {
       // A clang note with fix-it is not a separate diagnostic in clangd. We
       // attach it as a Fix to the main diagnostic instead.
@@ -788,7 +786,7 @@ void StoreDiags::flushLastDiag() {
     LastDiag.reset();
   });
 
-  if (isExcluded(*LastDiag))
+  if (LastDiag->Severity == DiagnosticsEngine::Ignored)
     return;
   // Move errors that occur from headers into main file.
   if (!LastDiag->InsideMainFile && LastDiagLoc && LastDiagOriginallyError) {

clang-tools-extra/clangd/Diagnostics.h

@@ -171,7 +171,6 @@ class StoreDiags : public DiagnosticConsumer {
   SourceManager *OrigSrcMgr = nullptr;
 
   llvm::DenseSet<std::pair<unsigned, unsigned>> IncludedErrorLocations;
-  bool LastPrimaryDiagnosticWasSuppressed = false;
 };
 
 /// Determine whether a (non-clang-tidy) diagnostic is suppressed by config.

clang-tools-extra/clangd/tool/ClangdMain.cpp

@@ -909,7 +909,11 @@ clangd accepts flags on the commandline, and in the CLANGD_FLAGS environment var
 
   if (CheckFile.getNumOccurrences()) {
     llvm::SmallString<256> Path;
-    llvm::sys::fs::real_path(CheckFile, Path, /*expand_tilde=*/true);
+    if (auto Error =
+            llvm::sys::fs::real_path(CheckFile, Path, /*expand_tilde=*/true)) {
+      elog("Failed to resolve path {0}: {1}", CheckFile, Error.message());
+      return 1;
+    }
     log("Entering check mode (no LSP server)");
     uint32_t Begin = 0, End = std::numeric_limits<uint32_t>::max();
     if (!CheckFileLines.empty()) {

clang-tools-extra/clangd/unittests/CompileCommandsTests.cpp

@@ -41,13 +41,14 @@ TEST(CommandMangler, Everything) {
   Mangler.ClangPath = testPath("fake/clang");
   Mangler.ResourceDir = testPath("fake/resources");
   Mangler.Sysroot = testPath("fake/sysroot");
-  std::vector<std::string> Cmd = {"clang++", "-Xclang", "-load", "-Xclang",
-                                  "plugin",  "-MF",     "dep",   "foo.cc"};
+  std::vector<std::string> Cmd = {"clang++", "-Xclang", "-load",
+                                  "-Xclang", "plugin",  "-MF",
+                                  "dep",     "--",      "foo.cc"};
   Mangler.adjust(Cmd);
-  EXPECT_THAT(Cmd, ElementsAre(testPath("fake/clang++"), "foo.cc",
-                               "-fsyntax-only",
+  EXPECT_THAT(Cmd, ElementsAre(testPath("fake/clang++"), "-fsyntax-only",
                                "-resource-dir=" + testPath("fake/resources"),
-                               "-isysroot", testPath("fake/sysroot")));
+                               "-isysroot", testPath("fake/sysroot"), "--",
+                               "foo.cc"));
 }
 
 TEST(CommandMangler, ResourceDir) {
@@ -378,4 +379,3 @@ TEST(PrintArgvTest, All) {
 } // namespace
 } // namespace clangd
 } // namespace clang
-

clang-tools-extra/clangd/unittests/ConfigCompileTests.cpp

@@ -123,12 +123,12 @@ TEST_F(ConfigCompileTests, Condition) {
 TEST_F(ConfigCompileTests, CompileCommands) {
   Frag.CompileFlags.Add.emplace_back("-foo");
   Frag.CompileFlags.Remove.emplace_back("--include-directory=");
-  std::vector<std::string> Argv = {"clang", "-I", "bar/", "a.cc"};
+  std::vector<std::string> Argv = {"clang", "-I", "bar/", "--", "a.cc"};
   EXPECT_TRUE(compileAndApply());
   EXPECT_THAT(Conf.CompileFlags.Edits, SizeIs(2));
   for (auto &Edit : Conf.CompileFlags.Edits)
     Edit(Argv);
-  EXPECT_THAT(Argv, ElementsAre("clang", "a.cc", "-foo"));
+  EXPECT_THAT(Argv, ElementsAre("clang", "-foo", "--", "a.cc"));
 }
 
 TEST_F(ConfigCompileTests, CompilationDatabase) {

clang-tools-extra/clangd/unittests/FeatureModulesTests.cpp

@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "Annotations.h"
 #include "FeatureModule.h"
 #include "Selection.h"
 #include "TestTU.h"
@@ -53,6 +54,37 @@ TEST(FeatureModulesTest, ContributesTweak) {
   EXPECT_EQ(Actual->get()->id(), TweakID);
 }
 
+TEST(FeatureModulesTest, SuppressDiags) {
+  struct DiagModifierModule final : public FeatureModule {
+    struct Listener : public FeatureModule::ASTListener {
+      void sawDiagnostic(const clang::Diagnostic &Info,
+                         clangd::Diag &Diag) override {
+        Diag.Severity = DiagnosticsEngine::Ignored;
+      }
+    };
+    std::unique_ptr<ASTListener> astListeners() override {
+      return std::make_unique<Listener>();
+    };
+  };
+  FeatureModuleSet FMS;
+  FMS.add(std::make_unique<DiagModifierModule>());
+
+  Annotations Code("[[test]]; /* error-ok */");
+  TestTU TU;
+  TU.Code = Code.code().str();
+
+  {
+    auto AST = TU.build();
+    EXPECT_THAT(*AST.getDiagnostics(), testing::Not(testing::IsEmpty()));
+  }
+
+  TU.FeatureModules = &FMS;
+  {
+    auto AST = TU.build();
+    EXPECT_THAT(*AST.getDiagnostics(), testing::IsEmpty());
+  }
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang

clang-tools-extra/test/clang-tidy/checkers/performance-unnecessary-copy-initialization.cpp

@@ -1,10 +1,20 @@
 // RUN: %check_clang_tidy %s performance-unnecessary-copy-initialization %t
 
+template <typename T>
+struct Iterator {
+  void operator++();
+  const T &operator*() const;
+  bool operator!=(const Iterator &) const;
+  typedef const T &const_reference;
+};
+
 struct ExpensiveToCopyType {
   ExpensiveToCopyType();
   virtual ~ExpensiveToCopyType();
   const ExpensiveToCopyType &reference() const;
   const ExpensiveToCopyType *pointer() const;
+  Iterator<ExpensiveToCopyType> begin() const;
+  Iterator<ExpensiveToCopyType> end() const;
   void nonConstMethod();
   bool constMethod() const;
 };
@@ -589,3 +599,41 @@ void positiveUnusedReferenceIsRemoved() {
   // CHECK-FIXES-NOT: auto TrailingCommentRemoved = ExpensiveTypeReference(); // Trailing comment.
   // clang-format on
 }
+
+void negativeloopedOverObjectIsModified() {
+  ExpensiveToCopyType Orig;
+  for (const auto &Element : Orig) {
+    const auto Copy = Element;
+    Orig.nonConstMethod();
+    Copy.constMethod();
+  }
+
+  auto Lambda = []() {
+    ExpensiveToCopyType Orig;
+    for (const auto &Element : Orig) {
+      const auto Copy = Element;
+      Orig.nonConstMethod();
+      Copy.constMethod();
+    }
+  };
+}
+
+void negativeReferenceIsInitializedOutsideOfBlock() {
+  ExpensiveToCopyType Orig;
+  const auto &E2 = Orig;
+  if (1 != 2 * 3) {
+    const auto C2 = E2;
+    Orig.nonConstMethod();
+    C2.constMethod();
+  }
+
+  auto Lambda = []() {
+    ExpensiveToCopyType Orig;
+    const auto &E2 = Orig;
+    if (1 != 2 * 3) {
+      const auto C2 = E2;
+      Orig.nonConstMethod();
+      C2.constMethod();
+    }
+  };
+}