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bzip2: code shrink

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function                                             old     new   delta
bsW16                                                  -      59     +59
sendMTFValues                                       2116    2111      -5
bsPutU16                                              36       -     -36
bsPutU32                                              76      31     -45
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 0/2 up/down: 59/-86)            Total: -27 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-02-02 20:59:28 +01:00
parent da49e7057a
commit 125c3ff4b1
1 changed files with 29 additions and 15 deletions
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44
archival/libarchive/bz/compress.c
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@ -75,25 +75,39 @@ void bsW(EState* s, int32_t n, uint32_t v)
s->bsBuff |= (v << (32 - s->bsLive - n));
s->bsLive += n;
}
/* Same with n == 16: */
static
#if CONFIG_BZIP2_FAST >= 5
ALWAYS_INLINE
#endif
void bsW16(EState* s, uint32_t v)
{
while (s->bsLive >= 8) {
s->zbits[s->numZ] = (uint8_t)(s->bsBuff >> 24);
s->numZ++;
s->bsBuff <<= 8;
s->bsLive -= 8;
}
s->bsBuff |= (v << (16 - s->bsLive));
s->bsLive += 16;
}
/*---------------------------------------------------*/
static ALWAYS_INLINE
void bsPutU16(EState* s, unsigned u)
{
bsW16(s, u);
}
/*---------------------------------------------------*/
static
void bsPutU32(EState* s, unsigned u)
{
bsW(s, 8, (u >> 24) & 0xff);
bsW(s, 8, (u >> 16) & 0xff);
bsW(s, 8, (u >> 8) & 0xff);
bsW(s, 8, u & 0xff);
}
/*---------------------------------------------------*/
static
void bsPutU16(EState* s, unsigned u)
{
bsW(s, 8, (u >> 8) & 0xff);
bsW(s, 8, u & 0xff);
//bsW(s, 32, u); // can't use: may try "uint32 << -n"
bsW16(s, (u >> 16) & 0xffff);
bsW16(s, u & 0xffff);
}
@ -509,7 +523,7 @@ void sendMTFValues(EState* s)
}
}
bsW(s, 16, inUse16);
bsW16(s, inUse16);
inUse16 <<= (sizeof(int)*8 - 16); /* move 15th bit into sign bit */
for (i = 0; i < 16; i++) {
@ -517,7 +531,7 @@ void sendMTFValues(EState* s)
unsigned v16 = 0;
for (j = 0; j < 16; j++)
v16 = v16*2 + s->inUse[i * 16 + j];
bsW(s, 16, v16);
bsW16(s, v16);
}
inUse16 <<= 1;
}