diff options
Diffstat (limited to 'lib/zlib_inflate/inffast.c')
| -rw-r--r-- | lib/zlib_inflate/inffast.c | 75 |
1 files changed, 68 insertions, 7 deletions
diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c index 8550b0c05d00..215447c55261 100644 --- a/lib/zlib_inflate/inffast.c +++ b/lib/zlib_inflate/inffast.c @@ -8,6 +8,21 @@ #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. @@ -24,9 +39,11 @@ #ifdef POSTINC # define OFF 0 # define PUP(a) *(a)++ +# define UP_UNALIGNED(a) get_unaligned((a)++) #else # define OFF 1 # define PUP(a) *++(a) +# define UP_UNALIGNED(a) get_unaligned(++(a)) #endif /* @@ -239,18 +256,62 @@ void inflate_fast(z_streamp strm, unsigned start) } } else { +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + unsigned short *sout; + unsigned long loops; + + from = out - dist; /* copy direct from output */ + /* minimum length is three */ + /* Align out addr */ + if (!((long)(out - 1 + OFF) & 1)) { + PUP(out) = PUP(from); + len--; + } + sout = (unsigned short *)(out - OFF); + if (dist > 2) { + unsigned short *sfrom; + + sfrom = (unsigned short *)(from - OFF); + loops = len >> 1; + do + PUP(sout) = UP_UNALIGNED(sfrom); + while (--loops); + out = (unsigned char *)sout + OFF; + from = (unsigned char *)sfrom + OFF; + } else { /* dist == 1 or dist == 2 */ + 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 + loops = len >> 1; + do + PUP(sout) = pat16; + while (--loops); + out = (unsigned char *)sout + OFF; + } + 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; + 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); + 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 */ |