emit_x64_vector: Special-case is_defaults_zero && table_size == 2 in EmitVectorTableLookup

This commit is contained in:
MerryMage 2018-08-19 21:32:54 +01:00
parent 9cc00f900c
commit 3bbcca8757

View file

@ -2741,6 +2741,26 @@ void EmitX64::EmitVectorTableLookup(EmitContext& ctx, IR::Inst* inst) {
return;
}
if (code.DoesCpuSupport(Xbyak::util::Cpu::tSSE41) && is_defaults_zero && table_size == 2) {
const Xbyak::Xmm indicies = ctx.reg_alloc.UseScratchXmm(args[2]);
const Xbyak::Xmm xmm_table0 = ctx.reg_alloc.UseScratchXmm(table[0]);
const Xbyak::Xmm xmm_table1 = ctx.reg_alloc.UseScratchXmm(table[1]);
if (code.DoesCpuSupport(Xbyak::util::Cpu::tAVX)) {
code.vpaddusb(xmm0, indicies, code.MConst(xword, 0x7070707070707070, 0x7070707070707070));
} else {
code.movaps(xmm0, indicies);
code.paddusb(xmm0, code.MConst(xword, 0x7070707070707070, 0x7070707070707070));
}
code.paddusb(indicies, code.MConst(xword, 0x6060606060606060, 0x6060606060606060));
code.pshufb(xmm_table0, xmm0);
code.pshufb(xmm_table1, indicies);
code.pblendvb(xmm_table0, xmm_table1);
ctx.reg_alloc.DefineValue(inst, xmm_table0);
return;
}
if (code.DoesCpuSupport(Xbyak::util::Cpu::tSSE41)) {
const Xbyak::Xmm indicies = ctx.reg_alloc.UseXmm(args[2]);
const Xbyak::Xmm result = ctx.reg_alloc.UseScratchXmm(args[0]);