[clang-tidy] Handle implicit casts in hicpp-signed-bitwise for IgnorePositiveIntegerLiterals (#90621)

Improved hicpp-signed-bitwise check by ignoring false positives
involving positive integer literals behind implicit casts when
IgnorePositiveIntegerLiterals is enabled.

Closes #89367

Author: PiotrZSL

clang-tools-extra/clang-tidy/hicpp/SignedBitwiseCheck.cpp

@@ -9,6 +9,7 @@
 #include "SignedBitwiseCheck.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
 
 using namespace clang::ast_matchers;
 using namespace clang::ast_matchers::internal;
@@ -29,8 +30,8 @@ void SignedBitwiseCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
 void SignedBitwiseCheck::registerMatchers(MatchFinder *Finder) {
   const auto SignedIntegerOperand =
       (IgnorePositiveIntegerLiterals
-           ? expr(ignoringImpCasts(hasType(isSignedInteger())),
-                  unless(integerLiteral()))
+           ? expr(ignoringImpCasts(
+                 allOf(hasType(isSignedInteger()), unless(integerLiteral()))))
            : expr(ignoringImpCasts(hasType(isSignedInteger()))))
           .bind("signed-operand");
 

clang-tools-extra/docs/ReleaseNotes.rst

@@ -259,6 +259,10 @@ Changes in existing checks
 - Improved :doc:`google-runtime-int <clang-tidy/checks/google/runtime-int>`
   check performance through optimizations.
 
+- Improved :doc:`hicpp-signed-bitwise <clang-tidy/checks/hicpp/signed-bitwise>`
+  check by ignoring false positives involving positive integer literals behind
+  implicit casts when `IgnorePositiveIntegerLiterals` is enabled.
+
 - Improved :doc:`hicpp-ignored-remove-result <clang-tidy/checks/hicpp/ignored-remove-result>`
   check by ignoring other functions with same prefixes as the target specific
   functions.

clang-tools-extra/test/clang-tidy/checkers/hicpp/signed-bitwise-integer-literals.cpp

@@ -11,6 +11,7 @@ void examples() {
   // CHECK-MESSAGES: :[[@LINE-1]]:19: warning: use of a signed integer operand with a binary bitwise operator
 
   unsigned URes2 = URes << 1; //Ok
+  unsigned URes3 = URes & 1; //Ok
 
   int IResult;
   IResult = 10 & 2; //Ok
@@ -21,6 +22,8 @@ void examples() {
   IResult = Int << 1;
   // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: use of a signed integer operand with a binary bitwise operator
   IResult = ~0; //Ok
+  IResult = -1 & 1;
+  // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: use of a signed integer operand with a binary bitwise operator [hicpp-signed-bitwise]
 }
 
 enum EnumConstruction {