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| author | Thom Johansen <thomj@rockbox.org> | 2006-03-17 02:05:39 +0000 |
|---|---|---|
| committer | Thom Johansen <thomj@rockbox.org> | 2006-03-17 02:05:39 +0000 |
| commit | 70ab7fc4e90141064c127e1207ee2f8d501f6356 (patch) | |
| tree | cb8044faf820c7012b54a2e4b5e653712e3488ef | |
| parent | 310d191f062094ea2ff82b523f97210d069ad418 (diff) | |
| download | rockbox-70ab7fc4e90141064c127e1207ee2f8d501f6356.zip rockbox-70ab7fc4e90141064c127e1207ee2f8d501f6356.tar.gz rockbox-70ab7fc4e90141064c127e1207ee2f8d501f6356.tar.bz2 rockbox-70ab7fc4e90141064c127e1207ee2f8d501f6356.tar.xz | |
Assembler optimised swap32 for ARM.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@9072 a1c6a512-1295-4272-9138-f99709370657
| -rw-r--r-- | firmware/export/system.h | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/firmware/export/system.h b/firmware/export/system.h index eb5bb52..150f872 100644 --- a/firmware/export/system.h +++ b/firmware/export/system.h @@ -463,9 +463,16 @@ static inline unsigned long swap32(unsigned long value) result[ 7.. 0] = value[31..24]; */ { - unsigned long hi = swap16(value >> 16); - unsigned long lo = swap16(value & 0xffff); - return (lo << 16) | hi; + unsigned int tmp; + + asm volatile ( + "eor %1, %0, %0, ror #16 \n\t" + "bic %1, %1, #0xff0000 \n\t" + "mov %0, %0, ror #8 \n\t" + "eor %0, %0, %1, lsr #8 \n\t" + : "+r" (value), "=r" (tmp) + ); + return value; } |