[alpha.webkit.RetainPtrCtorAdoptChecker] Recognize mutableCopy from literal as +1 (#132350)

This PR adds the support for recognizing the return value of copy /
mutableCopy as +1. isAllocInit and isOwned now traverses
PseudoObjectExpr to its last semantic expression.

Author: rniwa

clang/lib/StaticAnalyzer/Checkers/WebKit/RetainPtrCtorAdoptChecker.cpp

@@ -202,6 +202,12 @@ class RetainPtrCtorAdoptChecker
 
   bool isAllocInit(const Expr *E) const {
     auto *ObjCMsgExpr = dyn_cast<ObjCMessageExpr>(E);
+    if (auto *POE = dyn_cast<PseudoObjectExpr>(E)) {
+      if (unsigned ExprCount = POE->getNumSemanticExprs()) {
+        auto *Expr = POE->getSemanticExpr(ExprCount - 1)->IgnoreParenCasts();
+        ObjCMsgExpr = dyn_cast<ObjCMessageExpr>(Expr);
+      }
+    }
     if (!ObjCMsgExpr)
       return false;
     auto Selector = ObjCMsgExpr->getSelector();
@@ -247,6 +253,12 @@ class RetainPtrCtorAdoptChecker
   enum class IsOwnedResult { Unknown, Skip, Owned, NotOwned };
   IsOwnedResult isOwned(const Expr *E) const {
     while (1) {
+      if (auto *POE = dyn_cast<PseudoObjectExpr>(E)) {
+        if (unsigned SemanticExprCount = POE->getNumSemanticExprs()) {
+          E = POE->getSemanticExpr(SemanticExprCount - 1);
+          continue;
+        }
+      }
       if (isa<CXXNullPtrLiteralExpr>(E))
         return IsOwnedResult::NotOwned;
       if (auto *DRE = dyn_cast<DeclRefExpr>(E)) {

clang/test/Analysis/Checkers/WebKit/objc-mock-types.h

@@ -1,6 +1,8 @@
 @class NSString;
 @class NSArray;
 @class NSMutableArray;
+@class NSDictionary;
+@class NSMutableDictionary;
 #define nil ((id)0)
 #define CF_BRIDGED_TYPE(T) __attribute__((objc_bridge(T)))
 #define CF_BRIDGED_MUTABLE_TYPE(T) __attribute__((objc_bridge_mutable(T)))
@@ -95,12 +97,14 @@ __attribute__((objc_root_class))
 - (NSEnumerator *)keyEnumerator;
 + (id)dictionary;
 + (id)dictionaryWithObject:(id)object forKey:(id <NSCopying>)key;
+- (NSMutableDictionary *)mutableCopy;
 + (instancetype)dictionaryWithObjects:(const id [])objects forKeys:(const id <NSCopying> [])keys count:(NSUInteger)cnt;
 @end
 
 @interface NSArray : NSObject <NSCopying, NSFastEnumeration>
 - (NSUInteger)count;
 - (NSEnumerator *)objectEnumerator;
+- (NSMutableArray *)mutableCopy;
 + (NSArray *)arrayWithObjects:(const id [])objects count:(NSUInteger)count;
 @end
 
@@ -109,6 +113,7 @@ __attribute__((objc_root_class))
 - (NSString *)stringByAppendingString:(NSString *)aString;
 - ( const char *)UTF8String;
 - (id)initWithUTF8String:(const char *)nullTerminatedCString;
+- (NSString *)copy;
 + (id)stringWithUTF8String:(const char *)nullTerminatedCString;
 @end
 

clang/test/Analysis/Checkers/WebKit/retain-ptr-ctor-adopt-use-arc.mm

@@ -97,3 +97,19 @@ void create_member_init() {
 RetainPtr<id> return_bridge_cast() {
   return bridge_cast<CFArrayRef, NSArray>(create_cf_array());
 }
+
+void mutable_copy_dictionary() {
+  RetainPtr<NSMutableDictionary> mutableDictionary = adoptNS(@{
+    @"Content-Type": @"text/html",
+  }.mutableCopy);
+}
+
+void mutable_copy_array() {
+  RetainPtr<NSMutableArray> mutableArray = adoptNS(@[
+      @"foo",
+  ].mutableCopy);
+}
+
+void string_copy(NSString *str) {
+  RetainPtr<NSString> copy = adoptNS(str.copy);
+}

clang/test/Analysis/Checkers/WebKit/retain-ptr-ctor-adopt-use.mm

@@ -97,3 +97,19 @@ void create_member_init() {
 RetainPtr<id> return_bridge_cast() {
   return bridge_cast<CFArrayRef, NSArray>(create_cf_array());
 }
+
+void mutable_copy_dictionary() {
+  RetainPtr<NSMutableDictionary> mutableDictionary = adoptNS(@{
+    @"Content-Type": @"text/html",
+  }.mutableCopy);
+}
+
+void mutable_copy_array() {
+  RetainPtr<NSMutableArray> mutableArray = adoptNS(@[
+      @"foo",
+  ].mutableCopy);
+}
+
+void string_copy(NSString *str) {
+  RetainPtr<NSString> copy = adoptNS(str.copy);
+}