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Diffstat (limited to 'lib/zlib_inflate/inffast.c')
-rw-r--r--lib/zlib_inflate/inffast.c55
1 files changed, 44 insertions, 11 deletions
diff --git a/lib/zlib_inflate/inffast.c b/lib/zlib_inflate/inffast.c
index 8550b0c05d0..05e1559fa15 100644
--- a/lib/zlib_inflate/inffast.c
+++ b/lib/zlib_inflate/inffast.c
@@ -4,6 +4,8 @@
*/
#include <linux/zutil.h>
+#include <asm/unaligned.h>
+#include <asm/byteorder.h>
#include "inftrees.h"
#include "inflate.h"
#include "inffast.h"
@@ -24,9 +26,11 @@
#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 +243,47 @@ 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
+ 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 if ((op & 64) == 0) { /* 2nd level distance code */