[analyzer] Finish moving alpha.core.SizeofPtr to clang-tidy (#95118)

The checker `alpha.core.SizeofPtr` was a very simple checker that did
not rely on path sensitive analysis and was very similar to the (more
complex and refined) clang-tidy check `bugprone-sizeof-expression`.

As there is no reason to maintain two separate implementations for the
same goal (and clang-tidy is more lightweight and accessible than the
Analyzer) I decided to move this functionality from the Static Analyzer
to clang-tidy.

Recently my commit 546c816a529835a4cf89deecff957ea336a94fa2
reimplemented the advantageous parts of `alpha.core.SizeofPtr` within
clang-tidy; now this commit finishes the transfer by deleting
`alpha.core.SizeofPtr`.

6 files changed, 0 insertions, 140 deletions

diff --git a/clang/docs/analyzer/checkers.rst b/clang/docs/analyzer/checkers.rst
index f53dd54..d76ee24 100644
--- a/clang/docs/analyzer/checkers.rst
+++ b/clang/docs/analyzer/checkers.rst
@@ -2452,21 +2452,6 @@ Check for pointer subtractions on two pointers pointing to different memory chun
    int d = &y - &x; // warn
  }
 
-.. _alpha-core-SizeofPtr:
-
-alpha.core.SizeofPtr (C)
-""""""""""""""""""""""""
-Warn about unintended use of ``sizeof()`` on pointer expressions.
-
-.. code-block:: c
-
- struct s {};
-
- int test(struct s *p) {
-   return sizeof(p);
-     // warn: sizeof(ptr) can produce an unexpected result
- }
-
 .. _alpha-core-StackAddressAsyncEscape:
 
 alpha.core.StackAddressAsyncEscape (C)
diff --git a/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td b/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
index a7f62ef..429c334a 100644
--- a/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
+++ b/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
@@ -296,10 +296,6 @@ def PointerSubChecker : Checker<"PointerSub">,
            "different memory chunks">,
   Documentation<HasDocumentation>;
 
-def SizeofPointerChecker : Checker<"SizeofPtr">,
-  HelpText<"Warn about unintended use of sizeof() on pointer expressions">,
-  Documentation<HasDocumentation>;
-
 def TestAfterDivZeroChecker : Checker<"TestAfterDivZero">,
   HelpText<"Check for division by variable that is later compared against 0. "
            "Either the comparison is useless or there is division by zero.">,
diff --git a/clang/lib/StaticAnalyzer/Checkers/CMakeLists.txt b/clang/lib/StaticAnalyzer/Checkers/CMakeLists.txt
index 68e829c..682cfa0 100644
--- a/clang/lib/StaticAnalyzer/Checkers/CMakeLists.txt
+++ b/clang/lib/StaticAnalyzer/Checkers/CMakeLists.txt
@@ -24,7 +24,6 @@ add_clang_library(clangStaticAnalyzerCheckers
   CheckObjCInstMethSignature.cpp
   CheckPlacementNew.cpp
   CheckSecuritySyntaxOnly.cpp
-  CheckSizeofPointer.cpp
   CheckerDocumentation.cpp
   ChrootChecker.cpp
   CloneChecker.cpp
diff --git a/clang/lib/StaticAnalyzer/Checkers/CheckSizeofPointer.cpp b/clang/lib/StaticAnalyzer/Checkers/CheckSizeofPointer.cpp
deleted file mode 100644
index 0d2551f..0000000
--- a/clang/lib/StaticAnalyzer/Checkers/CheckSizeofPointer.cpp
+++ /dev/null
@@ -1,96 +0,0 @@
-//==- CheckSizeofPointer.cpp - Check for sizeof on pointers ------*- 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
-//
-//===----------------------------------------------------------------------===//
-//
-//  This file defines a check for unintended use of sizeof() on pointer
-//  expressions.
-//
-//===----------------------------------------------------------------------===//
-
-#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
-#include "clang/AST/StmtVisitor.h"
-#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
-#include "clang/StaticAnalyzer/Core/Checker.h"
-#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
-
-using namespace clang;
-using namespace ento;
-
-namespace {
-class WalkAST : public StmtVisitor<WalkAST> {
-  BugReporter &BR;
-  const CheckerBase *Checker;
-  AnalysisDeclContext* AC;
-
-public:
-  WalkAST(BugReporter &br, const CheckerBase *checker, AnalysisDeclContext *ac)
-      : BR(br), Checker(checker), AC(ac) {}
-  void VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *E);
-  void VisitStmt(Stmt *S) { VisitChildren(S); }
-  void VisitChildren(Stmt *S);
-};
-}
-
-void WalkAST::VisitChildren(Stmt *S) {
-  for (Stmt *Child : S->children())
-    if (Child)
-      Visit(Child);
-}
-
-// CWE-467: Use of sizeof() on a Pointer Type
-void WalkAST::VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *E) {
-  if (E->getKind() != UETT_SizeOf)
-    return;
-
-  // If an explicit type is used in the code, usually the coder knows what they are
-  // doing.
-  if (E->isArgumentType())
-    return;
-
-  QualType T = E->getTypeOfArgument();
-  if (T->isPointerType()) {
-
-    // Many false positives have the form 'sizeof *p'. This is reasonable
-    // because people know what they are doing when they intentionally
-    // dereference the pointer.
-    Expr *ArgEx = E->getArgumentExpr();
-    if (!isa<DeclRefExpr>(ArgEx->IgnoreParens()))
-      return;
-
-    PathDiagnosticLocation ELoc =
-      PathDiagnosticLocation::createBegin(E, BR.getSourceManager(), AC);
-    BR.EmitBasicReport(AC->getDecl(), Checker,
-                       "Potential unintended use of sizeof() on pointer type",
-                       categories::LogicError,
-                       "The code calls sizeof() on a pointer type. "
-                       "This can produce an unexpected result.",
-                       ELoc, ArgEx->getSourceRange());
-  }
-}
-
-//===----------------------------------------------------------------------===//
-// SizeofPointerChecker
-//===----------------------------------------------------------------------===//
-
-namespace {
-class SizeofPointerChecker : public Checker<check::ASTCodeBody> {
-public:
-  void checkASTCodeBody(const Decl *D, AnalysisManager& mgr,
-                        BugReporter &BR) const {
-    WalkAST walker(BR, this, mgr.getAnalysisDeclContext(D));
-    walker.Visit(D->getBody());
-  }
-};
-}
-
-void ento::registerSizeofPointerChecker(CheckerManager &mgr) {
-  mgr.registerChecker<SizeofPointerChecker>();
-}
-
-bool ento::shouldRegisterSizeofPointerChecker(const CheckerManager &mgr) {
-  return true;
-}
diff --git a/clang/test/Analysis/sizeofpointer.c b/clang/test/Analysis/sizeofpointer.c
deleted file mode 100644
index 14ddbd1..0000000
--- a/clang/test/Analysis/sizeofpointer.c
+++ /dev/null
@@ -1,8 +0,0 @@
-// RUN: %clang_analyze_cc1 -analyzer-checker=alpha.core.SizeofPtr -verify %s
-
-struct s {
-};
-
-int f(struct s *p) {
-  return sizeof(p); // expected-warning{{The code calls sizeof() on a pointer type. This can produce an unexpected result}}
-}
diff --git a/clang/www/analyzer/alpha_checks.html b/clang/www/analyzer/alpha_checks.html
index 411baae..501a9bc 100644
--- a/clang/www/analyzer/alpha_checks.html
+++ b/clang/www/analyzer/alpha_checks.html
@@ -239,22 +239,6 @@ void test() {
 </pre></div></div></td></tr>
 
 
-<tr><td><a id="alpha.core.SizeofPtr"><div class="namedescr expandable"><span class="name">
-alpha.core.SizeofPtr</span><span class="lang">
-(C)</span><div class="descr">
-Warn about unintended use of <code>sizeof()</code> on pointer
-expressions.</div></div></a></td>
-<td><div class="exampleContainer expandable">
-<div class="example"><pre>
-struct s {};
-
-int test(struct s *p) {
-  return sizeof(p);
-    // warn: sizeof(ptr) can produce an unexpected result
-}
-</pre></div></div></td></tr>
-
-
 <tr><td><a id="alpha.core.StackAddressAsyncEscape"><div class="namedescr expandable"><span class="name">
 alpha.core.StackAddressAsyncEscape</span><span class="lang">
 (C)</span><div class="descr">