emit_x64_floating_point: Factor out ConvertRoundingModeToX64Immediate

This commit is contained in:
MerryMage 2019-03-24 11:00:37 +00:00
parent 5a2adc6629
commit a53ba12be2

View file

@ -4,6 +4,7 @@
* General Public License version 2 or any later version.
*/
#include <optional>
#include <type_traits>
#include <utility>
@ -72,6 +73,21 @@ T ChooseOnFsize([[maybe_unused]] T f32, [[maybe_unused]] T f64) {
#define FCODE(NAME) (code.*ChooseOnFsize<fsize>(&Xbyak::CodeGenerator::NAME##s, &Xbyak::CodeGenerator::NAME##d))
std::optional<int> ConvertRoundingModeToX64Immediate(FP::RoundingMode rounding_mode) {
switch (rounding_mode) {
case FP::RoundingMode::ToNearest_TieEven:
return 0b00;
case FP::RoundingMode::TowardsPlusInfinity:
return 0b10;
case FP::RoundingMode::TowardsMinusInfinity:
return 0b01;
case FP::RoundingMode::TowardsZero:
return 0b11;
default:
return std::nullopt;
}
}
template<size_t fsize>
void DenormalsAreZero(BlockOfCode& code, Xbyak::Xmm xmm_value, Xbyak::Reg64 gpr_scratch) {
Xbyak::Label end;
@ -817,33 +833,18 @@ void EmitX64::EmitFPRecipStepFused64(EmitContext& ctx, IR::Inst* inst) {
}
static void EmitFPRound(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst, size_t fsize) {
const auto rounding = static_cast<FP::RoundingMode>(inst->GetArg(1).GetU8());
const auto rounding_mode = static_cast<FP::RoundingMode>(inst->GetArg(1).GetU8());
const bool exact = inst->GetArg(2).GetU1();
const auto round_imm = ConvertRoundingModeToX64Immediate(rounding_mode);
if (code.DoesCpuSupport(Xbyak::util::Cpu::tSSE41) && rounding != FP::RoundingMode::ToNearest_TieAwayFromZero && !exact) {
const int round_imm = [&]{
switch (rounding) {
case FP::RoundingMode::ToNearest_TieEven:
return 0b00;
case FP::RoundingMode::TowardsPlusInfinity:
return 0b10;
case FP::RoundingMode::TowardsMinusInfinity:
return 0b01;
case FP::RoundingMode::TowardsZero:
return 0b11;
default:
UNREACHABLE();
}
return 0;
}();
if (code.DoesCpuSupport(Xbyak::util::Cpu::tSSE41) && round_imm && !exact) {
if (fsize == 64) {
FPTwoOp<64>(code, ctx, inst, [&](Xbyak::Xmm result) {
code.roundsd(result, result, round_imm);
code.roundsd(result, result, *round_imm);
});
} else {
FPTwoOp<32>(code, ctx, inst, [&](Xbyak::Xmm result) {
code.roundss(result, result, round_imm);
code.roundss(result, result, *round_imm);
});
}
@ -887,7 +888,7 @@ static void EmitFPRound(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst, siz
ctx.reg_alloc.HostCall(inst, args[0]);
code.lea(code.ABI_PARAM2, code.ptr[code.r15 + code.GetJitStateInfo().offsetof_fpsr_exc]);
code.mov(code.ABI_PARAM3.cvt32(), ctx.FPCR().Value());
code.CallFunction(lut.at(std::make_tuple(fsize, rounding, exact)));
code.CallFunction(lut.at(std::make_tuple(fsize, rounding_mode, exact)));
}
void EmitX64::EmitFPRoundInt32(EmitContext& ctx, IR::Inst* inst) {
@ -1150,25 +1151,11 @@ static void EmitFPToFixed(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst) {
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
const size_t fbits = args[1].GetImmediateU8();
const auto rounding = static_cast<FP::RoundingMode>(args[2].GetImmediateU8());
const auto rounding_mode = static_cast<FP::RoundingMode>(args[2].GetImmediateU8());
const auto round_imm = ConvertRoundingModeToX64Immediate(rounding_mode);
if (code.DoesCpuSupport(Xbyak::util::Cpu::tSSE41) && rounding != FP::RoundingMode::ToNearest_TieAwayFromZero){
if (code.DoesCpuSupport(Xbyak::util::Cpu::tSSE41) && round_imm){
const Xbyak::Xmm src = ctx.reg_alloc.UseScratchXmm(args[0]);
const int round_imm = [&]{
switch (rounding) {
case FP::RoundingMode::ToNearest_TieEven:
default:
return 0b00;
case FP::RoundingMode::TowardsPlusInfinity:
return 0b10;
case FP::RoundingMode::TowardsMinusInfinity:
return 0b01;
case FP::RoundingMode::TowardsZero:
return 0b11;
}
}();
const Xbyak::Xmm scratch = ctx.reg_alloc.ScratchXmm();
const Xbyak::Reg64 result = ctx.reg_alloc.ScratchGpr().cvt64();
@ -1178,14 +1165,14 @@ static void EmitFPToFixed(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst) {
code.mulsd(src, code.MConst(xword, scale_factor));
}
code.roundsd(src, src, round_imm);
code.roundsd(src, src, *round_imm);
} else {
if (fbits != 0) {
const u32 scale_factor = static_cast<u32>((fbits + 127) << 23);
code.mulss(src, code.MConst(xword, scale_factor));
}
code.roundss(src, src, round_imm);
code.roundss(src, src, *round_imm);
code.cvtss2sd(src, src);
}
@ -1269,7 +1256,7 @@ static void EmitFPToFixed(BlockOfCode& code, EmitContext& ctx, IR::Inst* inst) {
ctx.reg_alloc.HostCall(inst, args[0]);
code.lea(code.ABI_PARAM2, code.ptr[code.r15 + code.GetJitStateInfo().offsetof_fpsr_exc]);
code.mov(code.ABI_PARAM3.cvt32(), ctx.FPCR().Value());
code.CallFunction(lut.at(std::make_tuple(fbits, rounding)));
code.CallFunction(lut.at(std::make_tuple(fbits, rounding_mode)));
}
void EmitX64::EmitFPDoubleToFixedS32(EmitContext& ctx, IR::Inst* inst) {