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

[Julian Schmidt via cfe-commits]

================
@@ -0,0 +1,67 @@
+//===------- NondetermnisticPointerUsageCheck.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 "NondeterministicPointerUsageCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::bugprone {
+
+void NondeterministicPointerUsageCheck::registerMatchers(MatchFinder *Finder) {
+
+  auto LoopVariable = varDecl(hasType(hasCanonicalType(pointerType())));
+
+  auto RangeInit = declRefExpr(to(varDecl(hasType(recordDecl(
+      anyOf(hasName("std::unordered_set"), hasName("std::unordered_map"),
+            hasName("std::unordered_multiset"),
+            hasName("std::unordered_multimap")))))));
+
+  Finder->addMatcher(
+      stmt(cxxForRangeStmt(hasRangeInit(RangeInit.bind("rangeinit")),
+                           hasLoopVariable(LoopVariable.bind("loopVar"))))
+          .bind("cxxForRangeStmt"),
+      this);
+
+  auto SortFuncM = anyOf(callee(functionDecl(hasName("std::is_sorted"))),
+                         callee(functionDecl(hasName("std::nth_element"))),
+                         callee(functionDecl(hasName("std::sort"))),
+                         callee(functionDecl(hasName("std::partial_sort"))),
+                         callee(functionDecl(hasName("std::partition"))),
+                         callee(functionDecl(hasName("std::stable_partition"))),
+                         callee(functionDecl(hasName("std::stable_sort"))));
+
+  auto IteratesPointerEltsM = hasArgument(
+      0,
+      cxxMemberCallExpr(on(hasType(cxxRecordDecl(has(fieldDecl(hasType(
+          hasCanonicalType(pointsTo(hasCanonicalType(pointerType())))))))))));
+
+  Finder->addMatcher(stmt(callExpr(allOf(SortFuncM, IteratesPointerEltsM)))
+                         .bind("sortsemantic"),
+                     this);
+}
+
+void NondeterministicPointerUsageCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *ForRangePointers =
+      Result.Nodes.getNodeAs<Stmt>("cxxForRangeStmt");
+  const auto *SortPointers = Result.Nodes.getNodeAs<Stmt>("sortsemantic");
+
+  if ((ForRangePointers) && !(ForRangePointers->getBeginLoc().isMacroID())) {
+    const auto *Node = dyn_cast<CXXForRangeStmt>(ForRangePointers);
+    diag(Node->getRParenLoc(), "Iteration of pointers is nondeterministic");
+  }
+
+  if ((SortPointers) && !(SortPointers->getBeginLoc().isMacroID())) {
+    const auto *Node = dyn_cast<Stmt>(SortPointers);
----------------
5chmidti wrote:

This is an unnecessary cast, given that `SortPointers` is already a `Stmt*`.

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