diff options
| author | Thiago Macieira <thiago.macieira@intel.com> | 2013-10-19 17:00:39 -0400 |
|---|---|---|
| committer | The Qt Project <gerrit-noreply@qt-project.org> | 2014-01-30 18:05:16 +0100 |
| commit | 07e831d7ff0662069491c22af953f4d6a9e2f3d9 (patch) | |
| tree | 15ecbc5750bc2dc4c5a1962a499185910e8dfcc5 | |
| parent | 1cc0a18d794c6795a053f833fe8a633e2553a2a9 (diff) | |
Declare qregister[u]int, an integer the size of the machine's word
In almost all platforms, sizeof(qregisterint) == sizeof(void*) ==
sizeof(qptrdiff). It's different for architectures that have a pointer
with a size different from the machine word. This allows us to declare
variables of the most optimal size, even if the pointers are too wide or
too narrow.
The only currently-known architectures to match that case are the ILP32
builds on x86-64 (a.k.a "x32") and IA-64 (option -milp32, only available
on HP-UXi), which have 64-bit registers but 32-bit pointers.
Change-Id: I0f126b70ea9ea326bd3143797287e4b98210d36d
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
| -rw-r--r-- | src/corelib/global/qglobal.h | 2 | ||||
| -rw-r--r-- | src/corelib/global/qprocessordetection.h | 21 |
2 files changed, 23 insertions, 0 deletions
diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h index e68246e607..1e9b20757d 100644 --- a/src/corelib/global/qglobal.h +++ b/src/corelib/global/qglobal.h @@ -437,6 +437,8 @@ template <> struct QIntegerForSize<2> { typedef quint16 Unsigned; typedef qin template <> struct QIntegerForSize<4> { typedef quint32 Unsigned; typedef qint32 Signed; }; template <> struct QIntegerForSize<8> { typedef quint64 Unsigned; typedef qint64 Signed; }; template <class T> struct QIntegerForSizeof: QIntegerForSize<sizeof(T)> { }; +typedef QIntegerForSize<Q_PROCESSOR_WORDSIZE>::Signed qregisterint; +typedef QIntegerForSize<Q_PROCESSOR_WORDSIZE>::Unsigned qregisteruint; typedef QIntegerForSizeof<void*>::Unsigned quintptr; typedef QIntegerForSizeof<void*>::Signed qptrdiff; typedef qptrdiff qintptr; diff --git a/src/corelib/global/qprocessordetection.h b/src/corelib/global/qprocessordetection.h index 623e30aa06..a5eff7c7ce 100644 --- a/src/corelib/global/qprocessordetection.h +++ b/src/corelib/global/qprocessordetection.h @@ -196,6 +196,7 @@ # define Q_PROCESSOR_X86 6 # define Q_PROCESSOR_X86_64 # define Q_BYTE_ORDER Q_LITTLE_ENDIAN +# define Q_PROCESSOR_WORDSIZE 8 /* Itanium (IA-64) family, no revisions or variants @@ -204,6 +205,7 @@ */ #elif defined(__ia64) || defined(__ia64__) || defined(_M_IA64) # define Q_PROCESSOR_IA64 +# define Q_PROCESSOR_WORDSIZE 8 // Q_BYTE_ORDER not defined, use endianness auto-detection /* @@ -324,4 +326,23 @@ # endif #endif +/* + Define Q_PROCESSOR_WORDSIZE to be the size of the machine's word (usually, + the size of the register). On some architectures where a pointer could be + smaller than the register, the macro is defined above. + + Try our best to define it to a literal, so it can be used in the preprocessor, + but fall back to sizeof(void*) on practically every 32-bit build. +*/ +#ifndef Q_PROCESSOR_WORDSIZE +# ifdef __SIZEOF_POINTER__ + /* GCC & friends define this */ +# define Q_PROCESSOR_WORDSIZE __SIZEOF_POINTER__ +# elif defined(_LP64) || defined(__LP64__) || defined(WIN64) || defined(_WIN64) +# define Q_PROCESSOR_WORDSIZE 8 +# else +# define Q_PROCESSOR_WORDSIZE sizeof(void*) +# endif +#endif + #endif // QPROCESSORDETECTION_H |