Zero register optimization for AVX-512-VBMI

- Take advantage of the fact that AVX instructions zero the upper 128 bits for a nice optimization when one input vector is zeroed
This commit is contained in:
Malcolm Jestadt 2023-07-21 13:58:54 -04:00 committed by Ivan
parent be0a789e7d
commit 290ff5b839

View File

@ -8674,6 +8674,20 @@ public:
{
if (data == v128::from8p(data._u8[0]))
{
if (m_use_avx512_icl)
{
if (perm_only)
{
set_vr(op.rt4, vperm2b256to128(as, b, c));
return;
}
const auto m = gf2p8affineqb(c, build<u8[16]>(0x40, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x40, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20), 0x7f);
const auto mm = select(noncast<s8[16]>(m) >= 0, splat<u8[16]>(0), m);
const auto ab = vperm2b256to128(as, b, c);
set_vr(op.rt4, select(noncast<s8[16]>(c) >= 0, ab, mm));
return;
}
// See above
const auto x = pshufb(build<u8[16]>(0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x80, 0x80), (c >> 4));
const auto ax = pshufb(as, c);
@ -8708,6 +8722,42 @@ public:
if (m_use_avx512_icl && (op.ra != op.rb || m_interp_magn))
{
if (auto [ok, data] = get_const_vector(b.value, m_pos); ok)
{
if (data == v128::from8p(data._u8[0]))
{
if (perm_only)
{
set_vr(op.rt4, vperm2b256to128(a, b, eval(c ^ 0xf)));
return;
}
const auto m = gf2p8affineqb(c, build<u8[16]>(0x40, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x40, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20), 0x7f);
const auto mm = select(noncast<s8[16]>(m) >= 0, splat<u8[16]>(0), m);
const auto ab = vperm2b256to128(a, b, eval(c ^ 0xf));
set_vr(op.rt4, select(noncast<s8[16]>(c) >= 0, ab, mm));
return;
}
}
if (auto [ok, data] = get_const_vector(a.value, m_pos); ok)
{
if (data == v128::from8p(data._u8[0]))
{
if (perm_only)
{
set_vr(op.rt4, vperm2b256to128(b, a, eval(c ^ 0x1f)));
return;
}
const auto m = gf2p8affineqb(c, build<u8[16]>(0x40, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x40, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20), 0x7f);
const auto mm = select(noncast<s8[16]>(m) >= 0, splat<u8[16]>(0), m);
const auto ab = vperm2b256to128(b, a, eval(c ^ 0x1f));
set_vr(op.rt4, select(noncast<s8[16]>(c) >= 0, ab, mm));
return;
}
}
if (perm_only)
{
set_vr(op.rt4, vperm2b(a, b, eval(c ^ 0xf)));