[clang] [clang-tools-extra] RFC: [clang-tidy] [analyzer] Move nondeterministic pointer usage check to tidy (PR #110471)

[Julian Schmidt via cfe-commits]

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@@ -0,0 +1,85 @@
+//===----- NondeterministicPointerIterationOrderCheck.cpp - clang-tidy ----===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "NondeterministicPointerIterationOrderCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::bugprone {
+
+void NondeterministicPointerIterationOrderCheck::registerMatchers(
+    MatchFinder *Finder) {
+
+  auto LoopVariable = varDecl(hasType(
+      qualType(hasCanonicalType(anyOf(referenceType(), pointerType())))));
+
+  auto RangeInit = declRefExpr(to(varDecl(
+      hasType(recordDecl(hasAnyName("std::unordered_set", "std::unordered_map",
+                                    "std::unordered_multiset",
+                                    "std::unordered_multimap"))
+                  .bind("recorddecl")))));
+
+  Finder->addMatcher(cxxForRangeStmt(hasLoopVariable(LoopVariable),
+                                     hasRangeInit(RangeInit.bind("rangeinit")))
+                         .bind("cxxForRangeStmt"),
+                     this);
+
+  auto SortFuncM = callee(functionDecl(hasAnyName(
+      "std::is_sorted", "std::nth_element", "std::sort", "std::partial_sort",
+      "std::partition", "std::stable_partition", "std::stable_sort")));
+
+  auto IteratesPointerEltsM = hasArgument(
+      0,
+      cxxMemberCallExpr(on(hasType(cxxRecordDecl(has(fieldDecl(hasType(qualType(
+          hasCanonicalType(pointsTo(hasCanonicalType(pointerType()))))))))))));
+
+  Finder->addMatcher(
+      callExpr(allOf(SortFuncM, IteratesPointerEltsM)).bind("sortsemantic"),
+      this);
+}
+
+void NondeterministicPointerIterationOrderCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *ForRangePointers =
+      Result.Nodes.getNodeAs<CXXForRangeStmt>("cxxForRangeStmt");
+
+  if ((ForRangePointers) && !(ForRangePointers->getBeginLoc().isMacroID())) {
+    const auto *RangeInit = Result.Nodes.getNodeAs<Stmt>("rangeinit");
+    if (const auto *ClassTemplate =
+            Result.Nodes.getNodeAs<ClassTemplateSpecializationDecl>(
+                "recorddecl")) {
+      const TemplateArgumentList &TemplateArgs =
+          ClassTemplate->getTemplateArgs();
+      const llvm::StringRef AlgoName = ClassTemplate->getName();
+      const bool Unordered = AlgoName.contains("unordered");
+      const bool SetLike = AlgoName.contains("set");
+      const bool MapLike = AlgoName.contains("map");
+      const bool IsAlgoArgPointer =
+          TemplateArgs[0].getAsType()->isPointerType();
+      assert(Unordered && "Expecting unordered algo!");
+      assert((SetLike ^ MapLike) &&
+             "Expecting either SetLike or Maplike Unordered Algo!");
----------------
5chmidti wrote:

Nit: swap `Algo` for `Class`

https://github.com/llvm/llvm-project/pull/110471