There is no particular patch/description which described the reason for this change but it was done as the part of zlib 1.2.3.5 release done by zlib commit d004b047838a ("zlib 1.2.3.5"). It is preparation for followup patch.
Signed-off-by: Michal Simek michal.simek@amd.com ---
lib/zlib/inffast.c | 20 ++++++++++---------- lib/zlib/inflate.c | 22 +++++++++++----------- lib/zlib/inflate.h | 2 +- 3 files changed, 22 insertions(+), 22 deletions(-)
diff --git a/lib/zlib/inffast.c b/lib/zlib/inffast.c index d61cf0e72af4..bdaa6d0dc51f 100644 --- a/lib/zlib/inffast.c +++ b/lib/zlib/inffast.c @@ -80,7 +80,7 @@ void inflate_fast(z_streamp strm, unsigned start) #endif unsigned wsize; /* window size or zero if not using window */ unsigned whave; /* valid bytes in the window */ - unsigned write; /* window write index */ + unsigned wnext; /* window write index */ unsigned char FAR *window; /* allocated sliding window, if wsize != 0 */ unsigned long hold; /* local strm->hold */ unsigned bits; /* local strm->bits */ @@ -115,7 +115,7 @@ void inflate_fast(z_streamp strm, unsigned start) #endif wsize = state->wsize; whave = state->whave; - write = state->write; + wnext = state->wnext; window = state->window; hold = state->hold; bits = state->bits; @@ -201,7 +201,7 @@ void inflate_fast(z_streamp strm, unsigned start) break; } from = window - OFF; - if (write == 0) { /* very common case */ + if (wnext == 0) { /* very common case */ from += wsize - op; if (op < len) { /* some from window */ len -= op; @@ -211,17 +211,17 @@ void inflate_fast(z_streamp strm, unsigned start) from = out - dist; /* rest from output */ } } - else if (write < op) { /* wrap around window */ - from += wsize + write - op; - op -= write; + else if (wnext < op) { /* wrap around window */ + from += wsize + wnext - op; + op -= wnext; if (op < len) { /* some from end of window */ len -= op; do { PUP(out) = PUP(from); } while (--op); from = window - OFF; - if (write < len) { /* some from start of window */ - op = write; + if (wnext < len) { /* some from start of window */ + op = wnext; len -= op; do { PUP(out) = PUP(from); @@ -231,7 +231,7 @@ void inflate_fast(z_streamp strm, unsigned start) } } else { /* contiguous in window */ - from += write - op; + from += wnext - op; if (op < len) { /* some from window */ len -= op; do { @@ -343,7 +343,7 @@ void inflate_fast(z_streamp strm, unsigned start) inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe): - Using bit fields for code structure - Different op definition to avoid & for extra bits (do & for table bits) - - Three separate decoding do-loops for direct, window, and write == 0 + - Three separate decoding do-loops for direct, window, and wnext == 0 - Special case for distance > 1 copies to do overlapped load and store copy - Explicit branch predictions (based on measured branch probabilities) - Deferring match copy and interspersed it with decoding subsequent codes diff --git a/lib/zlib/inflate.c b/lib/zlib/inflate.c index 8f767b7b9d2d..79c9e991aa33 100644 --- a/lib/zlib/inflate.c +++ b/lib/zlib/inflate.c @@ -21,7 +21,7 @@ int ZEXPORT inflateReset(z_streamp strm) state->head = Z_NULL; state->wsize = 0; state->whave = 0; - state->write = 0; + state->wnext = 0; state->hold = 0; state->bits = 0; state->lencode = state->distcode = state->next = state->codes; @@ -115,7 +115,7 @@ local int updatewindow(z_streamp strm, unsigned out) /* if window not in use yet, initialize */ if (state->wsize == 0) { state->wsize = 1U << state->wbits; - state->write = 0; + state->wnext = 0; state->whave = 0; }
@@ -123,22 +123,22 @@ local int updatewindow(z_streamp strm, unsigned out) copy = out - strm->avail_out; if (copy >= state->wsize) { zmemcpy(state->window, strm->next_out - state->wsize, state->wsize); - state->write = 0; + state->wnext = 0; state->whave = state->wsize; } else { - dist = state->wsize - state->write; + dist = state->wsize - state->wnext; if (dist > copy) dist = copy; - zmemcpy(state->window + state->write, strm->next_out - copy, dist); + zmemcpy(state->window + state->wnext, strm->next_out - copy, dist); copy -= dist; if (copy) { zmemcpy(state->window, strm->next_out - copy, copy); - state->write = copy; + state->wnext = copy; state->whave = state->wsize; } else { - state->write += dist; - if (state->write == state->wsize) state->write = 0; + state->wnext += dist; + if (state->wnext == state->wsize) state->wnext = 0; if (state->whave < state->wsize) state->whave += dist; } } @@ -823,12 +823,12 @@ int ZEXPORT inflate(z_streamp strm, int flush) copy = out - left; if (state->offset > copy) { /* copy from window */ copy = state->offset - copy; - if (copy > state->write) { - copy -= state->write; + if (copy > state->wnext) { + copy -= state->wnext; from = state->window + (state->wsize - copy); } else - from = state->window + (state->write - copy); + from = state->window + (state->wnext - copy); if (copy > state->length) copy = state->length; } else { /* copy from output */ diff --git a/lib/zlib/inflate.h b/lib/zlib/inflate.h index 07bd3e78a7c7..2657d611cda3 100644 --- a/lib/zlib/inflate.h +++ b/lib/zlib/inflate.h @@ -88,7 +88,7 @@ struct inflate_state { unsigned wbits; /* log base 2 of requested window size */ unsigned wsize; /* window size or zero if not using window */ unsigned whave; /* valid bytes in the window */ - unsigned write; /* window write index */ + unsigned wnext; /* window write index */ unsigned char FAR *window; /* allocated sliding window, if needed */ /* bit accumulator */ unsigned long hold; /* input bit accumulator */