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author | Joakim Tjernlund <joakim.tjernlund@transmode.se> | 2010-03-11 02:23:55 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-03-13 02:52:44 +0300 |
commit | e69eae65523b457a3ac4262a66cfff57f2c924a9 (patch) | |
tree | 620315728b7ebfe7876b9314206de8339e0343bb /lib/zlib_inflate | |
parent | 5ceaa2f39bfa73c4398cd01e78f1c3ebde3d3383 (diff) | |
download | linux-e69eae65523b457a3ac4262a66cfff57f2c924a9.tar.xz |
zlib: make new optimized inflate endian independent
Commit 6846ee5ca68d81e6baccf0d56221d7a00c1be18b ("zlib: Fix build of
powerpc boot wrapper") made the new optimized inflate only available on
arch's that define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS.
This patch will again enable the optimization for all arch's by defining
our own endian independent version of unaligned access. As an added
bonus, arch's that define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS do a
plain load instead.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/zlib_inflate')
-rw-r--r-- | lib/zlib_inflate/inffast.c | 70 |
1 files changed, 30 insertions, 40 deletions
diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c index 215447c55261..fa62fc7a94f9 100644 --- a/lib/zlib_inflate/inffast.c +++ b/lib/zlib_inflate/inffast.c @@ -8,21 +8,6 @@ #include "inflate.h" #include "inffast.h" -/* Only do the unaligned "Faster" variant when - * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set - * - * On powerpc, it won't be as we don't include autoconf.h - * automatically for the boot wrapper, which is intended as - * we run in an environment where we may not be able to deal - * with (even rare) alignment faults. In addition, we do not - * define __KERNEL__ for arch/powerpc/boot unlike x86 - */ - -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS -#include <asm/unaligned.h> -#include <asm/byteorder.h> -#endif - #ifndef ASMINF /* Allow machine dependent optimization for post-increment or pre-increment. @@ -36,14 +21,31 @@ - Pentium III (Anderson) - M68060 (Nikl) */ +union uu { + unsigned short us; + unsigned char b[2]; +}; + +/* Endian independed version */ +static inline unsigned short +get_unaligned16(const unsigned short *p) +{ + union uu mm; + unsigned char *b = (unsigned char *)p; + + mm.b[0] = b[0]; + mm.b[1] = b[1]; + return mm.us; +} + #ifdef POSTINC # define OFF 0 # define PUP(a) *(a)++ -# define UP_UNALIGNED(a) get_unaligned((a)++) +# define UP_UNALIGNED(a) get_unaligned16((a)++) #else # define OFF 1 # define PUP(a) *++(a) -# define UP_UNALIGNED(a) get_unaligned(++(a)) +# define UP_UNALIGNED(a) get_unaligned16(++(a)) #endif /* @@ -256,7 +258,6 @@ void inflate_fast(z_streamp strm, unsigned start) } } else { -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS unsigned short *sout; unsigned long loops; @@ -274,7 +275,11 @@ void inflate_fast(z_streamp strm, unsigned start) sfrom = (unsigned short *)(from - OFF); loops = len >> 1; do +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + PUP(sout) = PUP(sfrom); +#else PUP(sout) = UP_UNALIGNED(sfrom); +#endif while (--loops); out = (unsigned char *)sout + OFF; from = (unsigned char *)sfrom + OFF; @@ -282,14 +287,13 @@ void inflate_fast(z_streamp strm, unsigned start) unsigned short pat16; pat16 = *(sout-2+2*OFF); - if (dist == 1) -#if defined(__BIG_ENDIAN) - pat16 = (pat16 & 0xff) | ((pat16 & 0xff) << 8); -#elif defined(__LITTLE_ENDIAN) - pat16 = (pat16 & 0xff00) | ((pat16 & 0xff00) >> 8); -#else -#error __BIG_ENDIAN nor __LITTLE_ENDIAN is defined -#endif + if (dist == 1) { + union uu mm; + /* copy one char pattern to both bytes */ + mm.us = pat16; + mm.b[0] = mm.b[1]; + pat16 = mm.us; + } loops = len >> 1; do PUP(sout) = pat16; @@ -298,20 +302,6 @@ void inflate_fast(z_streamp strm, unsigned start) } if (len & 1) PUP(out) = PUP(from); -#else /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */ - from = out - dist; /* copy direct from output */ - do { /* minimum length is three */ - PUP(out) = PUP(from); - PUP(out) = PUP(from); - PUP(out) = PUP(from); - len -= 3; - } while (len > 2); - if (len) { - PUP(out) = PUP(from); - if (len > 1) - PUP(out) = PUP(from); - } -#endif /* !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */ } } else if ((op & 64) == 0) { /* 2nd level distance code */ |