diff options
Diffstat (limited to 'third_party/dav1d/src/x86/msac.asm')
| -rw-r--r-- | third_party/dav1d/src/x86/msac.asm | 172 |
1 files changed, 88 insertions, 84 deletions
diff --git a/third_party/dav1d/src/x86/msac.asm b/third_party/dav1d/src/x86/msac.asm index 9f05c921a6..4156efe914 100644 --- a/third_party/dav1d/src/x86/msac.asm +++ b/third_party/dav1d/src/x86/msac.asm @@ -143,10 +143,9 @@ cglobal msac_decode_symbol_adapt4, 0, 6, 6 mov esp, [esp] %endif %endif - not t4 sub t2d, t1d ; rng shl t1, gprsize*8-16 - add t4, t1 ; ~dif + sub t4, t1 ; dif - v .renorm3: mov t1d, [t0+msac.cnt] movifnidn t7, t0 @@ -157,33 +156,31 @@ cglobal msac_decode_symbol_adapt4, 0, 6, 6 shl t2d, cl shl t4, cl mov [t7+msac.rng], t2d - not t4 sub t1d, ecx jae .end ; no refill required ; refill: - mov t2, [t7+msac.buf] - mov rcx, [t7+msac.end] %if ARCH_X86_64 == 0 push t5 %endif - lea t5, [t2+gprsize] - cmp t5, rcx + mov t2, [t7+msac.buf] + mov t5, [t7+msac.end] + lea rcx, [t2+gprsize] + sub rcx, t5 ja .refill_eob - mov t2, [t2] - lea ecx, [t1+23] - add t1d, 16 - shr ecx, 3 ; shift_bytes - bswap t2 - sub t5, rcx - shl ecx, 3 ; shift_bits - shr t2, cl - sub ecx, t1d ; shift_bits - 16 - cnt - mov t1d, gprsize*8-16 - shl t2, cl - mov [t7+msac.buf], t5 - sub t1d, ecx ; cnt + gprsize*8 - shift_bits - xor t4, t2 + mov t5, [t2] + lea ecx, [t1+16-gprsize*8] + not t5 + bswap t5 + shr t5, cl + neg ecx + shr ecx, 3 ; num_bytes_read + or t4, t5 +.refill_end: + add t2, rcx + lea t1d, [t1+rcx*8] ; cnt += num_bits_read + mov [t7+msac.buf], t2 +.refill_end2: %if ARCH_X86_64 == 0 pop t5 %endif @@ -191,29 +188,35 @@ cglobal msac_decode_symbol_adapt4, 0, 6, 6 mov [t7+msac.cnt], t1d mov [t7+msac.dif], t4 RET +.pad_with_ones: + lea ecx, [t1-16] +%if ARCH_X86_64 + ror rcx, cl +%else + shr ecx, cl +%endif + or t4, rcx + jmp .refill_end2 .refill_eob: ; avoid overreading the input buffer - mov t5, rcx - mov ecx, gprsize*8-24 - sub ecx, t1d ; c -.refill_eob_loop: cmp t2, t5 - jae .refill_eob_end ; eob reached - movzx t1d, byte [t2] - inc t2 - shl t1, cl - xor t4, t1 - sub ecx, 8 - jge .refill_eob_loop -.refill_eob_end: - mov t1d, gprsize*8-24 -%if ARCH_X86_64 == 0 - pop t5 -%endif - sub t1d, ecx - mov [t7+msac.buf], t2 - mov [t7+msac.dif], t4 - mov [t7+msac.cnt], t1d - RET + jae .pad_with_ones ; eob reached + ; We can safely do a register-sized load of the last bytes of the buffer + ; as this code is only reached if the msac buffer size is >= gprsize. + mov t5, [t5-gprsize] + shl ecx, 3 + shr t5, cl + lea ecx, [t1+16-gprsize*8] + not t5 + bswap t5 + shr t5, cl + neg ecx + or t4, t5 + mov t5d, [t7+msac.end] + shr ecx, 3 + sub t5d, t2d ; num_bytes_left + cmp ecx, t5d + cmovae ecx, t5d ; num_bytes_read + jmp .refill_end cglobal msac_decode_symbol_adapt8, 0, 6, 6 DECODE_SYMBOL_ADAPT_INIT @@ -366,7 +369,6 @@ cglobal msac_decode_bool_adapt, 0, 6, 0 %if ARCH_X86_64 == 0 movzx eax, al %endif - not t4 test t3d, t3d jz m(msac_decode_symbol_adapt4, SUFFIX).renorm3 %if UNIX64 == 0 @@ -420,7 +422,6 @@ cglobal msac_decode_bool_equi, 0, 6, 0 mov ecx, 0xbfff setb al ; the upper 32 bits contains garbage but that's OK sub ecx, t2d - not t4 ; In this case of this function, (d =) 16 - clz(v) = 2 - (v >> 14) ; i.e. (0 <= d <= 2) and v < (3 << 14) shr ecx, 14 ; d @@ -447,7 +448,6 @@ cglobal msac_decode_bool, 0, 6, 0 cmovb t2d, t1d cmovb t4, t3 setb al - not t4 %if ARCH_X86_64 == 0 movzx eax, al %endif @@ -497,48 +497,45 @@ cglobal msac_decode_bool, 0, 6, 0 tzcnt eax, eax movzx ecx, word [buf+rax+16] movzx t2d, word [buf+rax+14] - not t4 %if ARCH_X86_64 add t6d, 5 %endif sub eax, 5 ; setup for merging the tok_br and tok branches sub t2d, ecx shl rcx, gprsize*8-16 - add t4, rcx + sub t4, rcx bsr ecx, t2d xor ecx, 15 shl t2d, cl shl t4, cl movd m2, t2d mov [t7+msac.rng], t2d - not t4 sub t5d, ecx jae %%end - mov t2, [t7+msac.buf] - mov rcx, [t7+msac.end] %if UNIX64 == 0 push t8 %endif - lea t8, [t2+gprsize] - cmp t8, rcx + mov t2, [t7+msac.buf] + mov t8, [t7+msac.end] + lea rcx, [t2+gprsize] + sub rcx, t8 ja %%refill_eob - mov t2, [t2] - lea ecx, [t5+23] - add t5d, 16 + mov t8, [t2] + lea ecx, [t5+16-gprsize*8] + not t8 + bswap t8 + shr t8, cl + neg ecx shr ecx, 3 - bswap t2 - sub t8, rcx - shl ecx, 3 - shr t2, cl - sub ecx, t5d - mov t5d, gprsize*8-16 - shl t2, cl - mov [t7+msac.buf], t8 + or t4, t8 +%%refill_end: + add t2, rcx + lea t5d, [t5+rcx*8] + mov [t7+msac.buf], t2 +%%refill_end2: %if UNIX64 == 0 pop t8 %endif - sub t5d, ecx - xor t4, t2 %%end: movp m3, t4 %if ARCH_X86_64 @@ -559,27 +556,34 @@ cglobal msac_decode_bool, 0, 6, 0 shr eax, 1 mov [t7+msac.cnt], t5d RET +%%pad_with_ones: + ; ensure that dif is padded with at least 15 bits of ones at the end + lea ecx, [t5-16] +%if ARCH_X86_64 + ror rcx, cl +%else + shr ecx, cl +%endif + or t4, rcx + jmp %%refill_end2 %%refill_eob: - mov t8, rcx - mov ecx, gprsize*8-24 - sub ecx, t5d -%%refill_eob_loop: cmp t2, t8 - jae %%refill_eob_end - movzx t5d, byte [t2] - inc t2 - shl t5, cl - xor t4, t5 - sub ecx, 8 - jge %%refill_eob_loop -%%refill_eob_end: -%if UNIX64 == 0 - pop t8 -%endif - mov t5d, gprsize*8-24 - mov [t7+msac.buf], t2 - sub t5d, ecx - jmp %%end + jae %%pad_with_ones + mov t8, [t8-gprsize] + shl ecx, 3 + shr t8, cl + lea ecx, [t5+16-gprsize*8] + not t8 + bswap t8 + shr t8, cl + neg ecx + or t4, t8 + mov t8d, [t7+msac.end] + shr ecx, 3 + sub t8d, t2d + cmp ecx, t8d + cmovae ecx, t8d + jmp %%refill_end %endmacro cglobal msac_decode_hi_tok, 0, 7 + ARCH_X86_64, 6 |