bzip2: have two separate "store bit 0" and "store bit 1" functions

function                                             old     new   delta
sendMTFValues                                       2051    2085     +34
bsW1_0                                                 -      33     +33
BZ2_compressBlock                                    225     223      -2
bsW1                                                  52       -     -52
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 1/1 up/down: 67/-54)             Total: 13 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/archival/libarchive/bz/compress.c b/archival/libarchive/bz/compress.c
index 4d0f77592838bfb4dfb1f3b7628d1273e0cad48d..fc6af6595de4dc20ae60423cbfc534d7f8450a08 100644 (file)
--- a/archival/libarchive/bz/compress.c
+++ b/archival/libarchive/bz/compress.c
@@ -90,10 +90,23 @@ void bsW16(EState* s, uint32_t v)
 }
 /* Same with n == 1: */
 static
+ALWAYS_INLINE /* one callsite */
+void bsW1_1(EState* s)
+{
+       /* need space for only 1 bit, no need for loop freeing > 8 bits */
+       if (s->bsLive >= 8) {
+               *s->posZ++ = (uint8_t)(s->bsBuff >> 24);
+               s->bsBuff <<= 8;
+               s->bsLive -= 8;
+       }
+       s->bsBuff |= (1 << (31 - s->bsLive));
+       s->bsLive += 1;
+}
+static
 #if CONFIG_BZIP2_FAST >= 5
 ALWAYS_INLINE
 #endif
-void bsW1(EState* s, uint32_t v)
+void bsW1_0(EState* s)
 {
        /* need space for only 1 bit, no need for loop freeing > 8 bits */
        if (s->bsLive >= 8) {
@@ -101,7 +114,7 @@ void bsW1(EState* s, uint32_t v)
                s->bsBuff <<= 8;
                s->bsLive -= 8;
        }
-       s->bsBuff |= (v << (31 - s->bsLive));
+       //s->bsBuff |= (0 << (31 - s->bsLive));
        s->bsLive += 1;
 }
 
@@ -573,8 +586,8 @@ void sendMTFValues(EState* s)
        for (i = 0; i < nSelectors; i++) {
                unsigned j;
                for (j = 0; j < s->selectorMtf[i]; j++)
-                       bsW1(s, 1);
-               bsW1(s, 0);
+                       bsW1_1(s);
+               bsW1_0(s);
        }
 
        /*--- Now the coding tables. ---*/
@@ -584,7 +597,7 @@ void sendMTFValues(EState* s)
                for (i = 0; i < alphaSize; i++) {
                        while (curr < s->len[t][i]) { bsW(s, 2, 2); curr++; /* 10 */ };
                        while (curr > s->len[t][i]) { bsW(s, 2, 3); curr--; /* 11 */ };
-                       bsW1(s, 0);
+                       bsW1_0(s);
                }
        }
 
@@ -698,7 +711,7 @@ void BZ2_compressBlock(EState* s, int is_last_block)
                 * so as to maintain backwards compatibility with
                 * older versions of bzip2.
                 */
-               bsW1(s, 0);
+               bsW1_0(s);
 
                bsW(s, 24, s->origPtr);
                generateMTFValues(s);