From e69eae65523b457a3ac4262a66cfff57f2c924a9 Mon Sep 17 00:00:00 2001 From: Joakim Tjernlund Date: Wed, 10 Mar 2010 15:23:55 -0800 Subject: [PATCH] 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 Cc: Anton Blanchard Cc: Benjamin Herrenschmidt Cc: David Woodhouse Cc: Kumar Gala Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/zlib_inflate/inffast.c | 70 ++++++++++++++++---------------------- 1 file 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 -#include -#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 */