From: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
To: git@vger.kernel.org
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Subject: [PATCH v3 0/5] bswap.h: Rework ntohl handling
Date: Tue, 15 Jul 2025 21:12:25 +0200 [thread overview]
Message-ID: <20250715191230.12081-1-sebastian@breakpoint.cc> (raw)
Hi,
this series continues the rework of the bswap32/64()/ nothl() handling.
I've been looking at recent compiler and they manage to recognize the
manual shifting and use an optimize opcode if available. The ntohl
version provided by glibc already provides an "optimized" version which
makes an optimisation in git almost not needed.
One of the motivation behind overwriting/ providing an optimized
version was to provide a macro instead of using a function call. One
libc that is still providing ntohl as a function call is musl.
While ntohl() is provided by the libc, the ntohll() is not. I found it
only on Windows provided by winsock.h.
I haven't touched the put/get_be*() macros. gcc & clang are both smart
enough to swap the content accordingly and perform a single store/ load.
Only the msvc seems to strugle here and performs multiple bytes stores/
loads and shifts.
v2…v3 https://lore.kernel.org/all/20250611221444.1567638-1-sebastian@breakpoint.cc/
- Fixed typos in the patch description
Sebastian Andrzej Siewior (5):
bswap.h: Add support for __BYTE_ORDER__
bswap.h: Define GIT_LITTLE_ENDIAN on msvc as little endian
bswap.h: Always overwrite ntohl/ ntohll macros
bswap.h: Remove optimized x86 version of bswap32/64
bswap.h: Provide a built-in based version of bswap32/64 if possible
compat/bswap.h | 114 +++++++++++++++++++++----------------------------
1 file changed, 48 insertions(+), 66 deletions(-)
--
2.50.0
next reply other threads:[~2025-07-15 19:12 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-15 19:12 Sebastian Andrzej Siewior [this message]
2025-07-15 19:12 ` [PATCH v3 1/5] bswap.h: Add support for __BYTE_ORDER__ Sebastian Andrzej Siewior
2025-07-15 19:12 ` [PATCH v3 2/5] bswap.h: Define GIT_LITTLE_ENDIAN on msvc as little endian Sebastian Andrzej Siewior
2025-07-15 19:12 ` [PATCH v3 3/5] bswap.h: Always overwrite ntohl/ ntohll macros Sebastian Andrzej Siewior
2025-07-15 19:12 ` [PATCH v3 4/5] bswap.h: Remove optimized x86 version of bswap32/64 Sebastian Andrzej Siewior
2025-07-15 19:12 ` [PATCH v3 5/5] bswap.h: Provide a built-in based version of bswap32/64 if possible Sebastian Andrzej Siewior
2025-07-15 21:52 ` [PATCH v3 0/5] bswap.h: Rework ntohl handling Junio C Hamano
2025-07-15 22:36 ` brian m. carlson
2025-07-16 5:01 ` Sebastian Andrzej Siewior
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