Changeset 64302 in webkit for trunk/JavaScriptCore/wtf/StdLibExtras.h

Timestamp:

Jul 29, 2010, 12:52:22 PM (15 years ago)

Author:

Csaba Osztrogonác

Message:

2010-07-29 Gabor Loki <​[email protected]>

Reviewed by Gavin Barraclough.

Avoid increasing required alignment of target type warning on ARM
​https://bugs.webkit.org/show_bug.cgi?id=38045

The reinterpret_cast<Type1*>([pointer to Type2]) expressions - where
sizeof(Type1) > sizeof(Type2) - cause the following warning on ARM:
increases required alignment of target type warnings.
Casting the type of [pointer to Type2] object to void* bypasses the
warning.

• assembler/ARMAssembler.cpp: (JSC::ARMAssembler::executableCopy):
• assembler/AssemblerBuffer.h: (JSC::AssemblerBuffer::putShortUnchecked): (JSC::AssemblerBuffer::putIntUnchecked): (JSC::AssemblerBuffer::putInt64Unchecked):
• jit/JITStubs.cpp:
• pcre/pcre_compile.cpp: (jsRegExpCompile):
• wtf/FastMalloc.cpp: (WTF::PageHeapAllocator::New): (WTF::TCMalloc_Central_FreeList::Populate):
• wtf/MD5.cpp: (WTF::reverseBytes): (WTF::MD5::addBytes): (WTF::MD5::checksum):
• wtf/StdLibExtras.h: (reinterpret_cast_ptr):
• wtf/Vector.h: (WTF::VectorBuffer::inlineBuffer):
• wtf/qt/StringQt.cpp: (WebCore::String::String):

File:

• trunk/JavaScriptCore/wtf/StdLibExtras.h (modified) (1 diff)

trunk/JavaScriptCore/wtf/StdLibExtras.h

@@ -52 +52 @@
 #define STRINGIZE_VALUE_OF(exp) STRINGIZE(exp)
 
+/*
+ * The reinterpret_cast<Type1*>([pointer to Type2]) expressions - where
+ * sizeof(Type1) > sizeof(Type2) - cause the following warning on ARM with GCC:
+ * increases required alignment of target type.
+ *
+ * An implicit or an extra static_cast<void*> bypasses the warning.
+ * For more info see the following bugzilla entries:
+ * - https://bugs.webkit.org/show_bug.cgi?id=38045
+ * - http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43976
+ */
+#if CPU(ARM) && COMPILER(GCC)
+template<typename T>
+T reinterpret_cast_ptr(void* ptr)
+{
+    ASSERT(!(reinterpret_cast<unsigned int>(ptr) % __alignof__(T)));
+    return reinterpret_cast<T>(ptr);
+}
+template<typename T>
+T reinterpret_cast_ptr(const void* ptr)
+{
+    ASSERT(!(reinterpret_cast<unsigned int>(ptr) % __alignof__(T)));
+    return reinterpret_cast<T>(ptr);
+}
+#else
+#define reinterpret_cast_ptr reinterpret_cast
+#endif
+
 namespace WTF {