[clang-tools-extra] [clang-tidy][NFCI] Simplify bugprone-sizeof-expression (PR #93024)

[Donát Nagy via cfe-commits]

https://github.com/NagyDonat updated https://github.com/llvm/llvm-project/pull/93024

>From b7fb1707601c73bd53b6ac810cd39a94f5b3cd53 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Don=C3=A1t=20Nagy?= <donat.nagy at ericsson.com>
Date: Wed, 22 May 2024 13:45:13 +0200
Subject: [PATCH 1/3] [clang-tidy][NFCI] Simplify bugprone-sizeof-expression

This commit eliminates a redundant matcher subexpression from the
implementation of the "sizeof-pointer-to-aggregate" part of the
clang-tidy check `bugprone-sizeof-expression`.

I'm fairly certain that anything that was previously matched by the
deleted matcher `StructAddrOfExpr` is also covered by the more general
`PointerToStructExpr` (which remains in the same `anyOf`).

This commit is made to "prepare the ground" for a followup change that
would merge the functionality of the Clang Static Analyzer checker
`alpha.core.SizeofPtr` into this clang-tidy check.
---
 .../clang-tidy/bugprone/SizeofExpressionCheck.cpp        | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
index a1cffbc666199..f119711638111 100644
--- a/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
@@ -147,9 +147,6 @@ void SizeofExpressionCheck::registerMatchers(MatchFinder *Finder) {
     const auto PointerToArrayExpr = ignoringParenImpCasts(
         hasType(hasCanonicalType(pointerType(pointee(arrayType())))));
 
-    const auto StructAddrOfExpr = unaryOperator(
-        hasOperatorName("&"), hasUnaryOperand(ignoringParenImpCasts(
-                                  hasType(hasCanonicalType(recordType())))));
     const auto PointerToStructType =
         hasUnqualifiedDesugaredType(pointerType(pointee(recordType())));
     const auto PointerToStructExpr = ignoringParenImpCasts(expr(
@@ -171,9 +168,9 @@ void SizeofExpressionCheck::registerMatchers(MatchFinder *Finder) {
                                            has(ArrayOfPointersExpr)))))))),
              sizeOfExpr(has(ArrayOfSamePointersZeroSubscriptExpr)));
 
-    Finder->addMatcher(expr(anyOf(sizeOfExpr(has(ignoringParenImpCasts(anyOf(
-                                      ArrayCastExpr, PointerToArrayExpr,
-                                      StructAddrOfExpr, PointerToStructExpr)))),
+    Finder->addMatcher(expr(anyOf(sizeOfExpr(has(ignoringParenImpCasts(
+                                      anyOf(ArrayCastExpr, PointerToArrayExpr,
+                                            PointerToStructExpr)))),
                                   sizeOfExpr(has(PointerToStructType))),
                             unless(ArrayLengthExprDenom))
                            .bind("sizeof-pointer-to-aggregate"),

>From 89552a0539b587e9fcbc431db0d9ad6511f36050 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Don=C3=A1t=20Nagy?= <donat.nagy at ericsson.com>
Date: Wed, 22 May 2024 14:10:31 +0200
Subject: [PATCH 2/3] Simplify some matcher expressions

Eliminate a few redundant `ignoreParenImpCasts` calls and simplify the
final matcher expression.
---
 .../bugprone/SizeofExpressionCheck.cpp        | 23 ++++++++++---------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
index f119711638111..913be196a29b5 100644
--- a/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
@@ -144,13 +144,13 @@ void SizeofExpressionCheck::registerMatchers(MatchFinder *Finder) {
         unaryOperator(hasUnaryOperand(ArrayExpr), unless(hasOperatorName("*"))),
         binaryOperator(hasEitherOperand(ArrayExpr)),
         castExpr(hasSourceExpression(ArrayExpr))));
-    const auto PointerToArrayExpr = ignoringParenImpCasts(
-        hasType(hasCanonicalType(pointerType(pointee(arrayType())))));
+    const auto PointerToArrayExpr =
+        hasType(hasCanonicalType(pointerType(pointee(arrayType()))));
 
     const auto PointerToStructType =
         hasUnqualifiedDesugaredType(pointerType(pointee(recordType())));
-    const auto PointerToStructExpr = ignoringParenImpCasts(expr(
-        hasType(hasCanonicalType(PointerToStructType)), unless(cxxThisExpr())));
+    const auto PointerToStructExpr = expr(
+        hasType(hasCanonicalType(PointerToStructType)), unless(cxxThisExpr()));
 
     const auto ArrayOfPointersExpr = ignoringParenImpCasts(
         hasType(hasCanonicalType(arrayType(hasElementType(pointerType()))
@@ -168,13 +168,14 @@ void SizeofExpressionCheck::registerMatchers(MatchFinder *Finder) {
                                            has(ArrayOfPointersExpr)))))))),
              sizeOfExpr(has(ArrayOfSamePointersZeroSubscriptExpr)));
 
-    Finder->addMatcher(expr(anyOf(sizeOfExpr(has(ignoringParenImpCasts(
-                                      anyOf(ArrayCastExpr, PointerToArrayExpr,
-                                            PointerToStructExpr)))),
-                                  sizeOfExpr(has(PointerToStructType))),
-                            unless(ArrayLengthExprDenom))
-                           .bind("sizeof-pointer-to-aggregate"),
-                       this);
+    Finder->addMatcher(
+        expr(sizeOfExpr(anyOf(
+                 has(ignoringParenImpCasts(anyOf(
+                     ArrayCastExpr, PointerToArrayExpr, PointerToStructExpr))),
+                 has(PointerToStructType))),
+             unless(ArrayLengthExprDenom))
+            .bind("sizeof-pointer-to-aggregate"),
+        this);
   }
 
   // Detect expression like: sizeof(expr) <= k for a suspicious constant 'k'.

>From c6dcbd59d287f0238fbddeb51633228fba6099a4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Don=C3=A1t=20Nagy?= <donat.nagy at ericsson.com>
Date: Wed, 22 May 2024 14:22:45 +0200
Subject: [PATCH 3/3] Remove another useless ignoringParenImpCasts() call

The traversal matcher `hasParent` moves a single layer outwards, so it
cannot skip over paren or implicit cast layers that could be ignored at
that point.
---
 .../clang-tidy/bugprone/SizeofExpressionCheck.cpp           | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
index 913be196a29b5..5e64d23874ec1 100644
--- a/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
+++ b/clang-tools-extra/clang-tidy/bugprone/SizeofExpressionCheck.cpp
@@ -163,9 +163,9 @@ void SizeofExpressionCheck::registerMatchers(MatchFinder *Finder) {
         ignoringParenImpCasts(arraySubscriptExpr(
             hasBase(ArrayOfSamePointersExpr), hasIndex(ZeroLiteral)));
     const auto ArrayLengthExprDenom =
-        expr(hasParent(expr(ignoringParenImpCasts(binaryOperator(
-                 hasOperatorName("/"), hasLHS(ignoringParenImpCasts(sizeOfExpr(
-                                           has(ArrayOfPointersExpr)))))))),
+        expr(hasParent(binaryOperator(hasOperatorName("/"),
+                                      hasLHS(ignoringParenImpCasts(sizeOfExpr(
+                                          has(ArrayOfPointersExpr)))))),
              sizeOfExpr(has(ArrayOfSamePointersZeroSubscriptExpr)));
 
     Finder->addMatcher(