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| author | Denys Vlasenko <vda.linux@googlemail.com> | 2018-01-31 00:42:29 +0100 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2018-01-31 00:42:29 +0100 |
| commit | 631c16855a05f0699149502bba93a3ad8f88608e (patch) | |
| tree | 6eeb9b56710ae8159d95c234fc98315fb84dbde2 /archival/gzip.c | |
| parent | b7dfbbcdaaae5267259e2272b1cdfde6daad44a0 (diff) | |
| download | busybox-631c16855a05f0699149502bba93a3ad8f88608e.tar.gz | |
gzip: optionally faster put_32bit()
function old new delta
put_32bit 22 55 +33
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'archival/gzip.c')
| -rw-r--r-- | archival/gzip.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/archival/gzip.c b/archival/gzip.c index 08633d667..5812f4b27 100644 --- a/archival/gzip.c +++ b/archival/gzip.c @@ -454,7 +454,7 @@ static void put_16bit(ush w) if (outcnt < OUTBUFSIZ-2) { /* Common case */ ush *dst16 = (void*) dst; - *dst16 = w; /* unalinged LSB 16-bit store */ + *dst16 = w; /* unaligned LSB 16-bit store */ G1.outcnt = outcnt + 2; return; } @@ -480,6 +480,18 @@ static void put_16bit(ush w) static void put_32bit(ulg n) { +#if CONFIG_GZIP_FAST > 0 \ + && BB_UNALIGNED_MEMACCESS_OK && BB_LITTLE_ENDIAN + unsigned outcnt = G1.outcnt; + if (outcnt < OUTBUFSIZ-4) { + /* Common case */ + uch *dst = &G1.outbuf[outcnt]; + ulg *dst32 = (void*) dst; + *dst32 = n; /* unaligned LSB 32-bit store */ + G1.outcnt = outcnt + 4; + return; + } +#endif put_16bit(n); put_16bit(n >> 16); } @@ -544,7 +556,7 @@ static void send_bits(unsigned value, unsigned length) */ value >>= (BUF_SIZE - G1.bi_valid); if (BUF_SIZE == 32) { - put_32bit(new_buf); /* maybe unroll to 2*put_16bit()? */ + put_32bit(new_buf); } else { /* 16 */ put_16bit(new_buf); } |