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authorH. Peter Anvin <hpa@zytor.com>2010-04-29 16:53:17 -0700
committerH. Peter Anvin <hpa@zytor.com>2010-04-29 16:53:17 -0700
commitd9c5841e22231e4e49fd0a1004164e6fce59b7a6 (patch)
treee1f589c46b3ff79bbe7b1b2469f6362f94576da6 /lib/zlib_inflate/inffast.c
parentb701a47ba48b698976fb2fe05fb285b0edc1d26a (diff)
parent5967ed87ade85a421ef814296c3c7f182b08c225 (diff)
Merge branch 'x86/asm' into x86/atomic
Merge reason: Conflict between LOCK_PREFIX_HERE and relative alternatives pointers Resolved Conflicts: arch/x86/include/asm/alternative.h arch/x86/kernel/alternative.c Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'lib/zlib_inflate/inffast.c')
-rw-r--r--lib/zlib_inflate/inffast.c73
1 files changed, 62 insertions, 11 deletions
diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c
index 8550b0c05d0..2c13ecc5bb2 100644
--- a/lib/zlib_inflate/inffast.c
+++ b/lib/zlib_inflate/inffast.c
@@ -21,12 +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_unaligned16((a)++)
#else
# define OFF 1
# define PUP(a) *++(a)
+# define UP_UNALIGNED(a) get_unaligned16(++(a))
#endif
/*
@@ -239,18 +258,50 @@ void inflate_fast(z_streamp strm, unsigned start)
}
}
else {
+ unsigned short *sout;
+ unsigned long loops;
+
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);
- }
+ /* 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
+#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;
+ } else { /* dist == 1 or dist == 2 */
+ unsigned short pat16;
+
+ pat16 = *(sout-1+OFF);
+ 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;
+ while (--loops);
+ out = (unsigned char *)sout + OFF;
+ }
+ if (len & 1)
+ PUP(out) = PUP(from);
}
}
else if ((op & 64) == 0) { /* 2nd level distance code */