z80_unpacker: optimisations: -4T per offset/length bit decoded

making the 256-alignment of probs array even more baked-in, but there
was no real chance to get rid of that any way
This commit is contained in:
Peter Helcmanovsky (Ped)
2022-09-14 00:01:51 +02:00
parent d30baaa91f
commit 511ddefc08

View File

@@ -270,11 +270,11 @@ decode_length:
ld de,$7FFF ; length = 0 with positional-stop-bit ld de,$7FFF ; length = 0 with positional-stop-bit
jr .loop_entry jr .loop_entry
.loop: .loop:
inc bc ; context_index + 1 ; TODO can be just `inc c` for 257.. and 257+64.. contexts inc c ; context_index + 1
call decode_bit call decode_bit
rr d rr d
rr e ; DE = length = (length >> 1) | (bit << 15); rr e ; DE = length = (length >> 1) | (bit << 15);
inc bc ; context_index += 2 ; TODO can be just `inc c` for 257.. and 257+64.. contexts inc c ; context_index += 2
.loop_entry: .loop_entry:
call decode_bit call decode_bit
jr c,.loop jr c,.loop