thumb32: Implement SSAT16/USAT16

This commit is contained in:
Lioncash 2021-02-25 09:01:52 -05:00
parent ac32175eff
commit ba7cbe7cf6
3 changed files with 39 additions and 2 deletions

View file

@ -78,13 +78,13 @@ INST(thumb32_MOVW_imm, "MOVW (imm)", "11110i100100iiii0iiidd
//INST(thumb32_SUB_imm_2, "SUB (imm)", "11110-101010----0---------------")
INST(thumb32_MOVT, "MOVT", "11110i101100iiii0iiiddddiiiiiiii")
//INST(thumb32_SSAT, "SSAT", "11110-110000----0---------------")
//INST(thumb32_SSAT16, "SSAT16", "11110-110010----0000----00------")
INST(thumb32_SSAT16, "SSAT16", "111100110010nnnn0000dddd0000iiii")
//INST(thumb32_SSAT, "SSAT", "11110-110010----0---------------")
//INST(thumb32_SBFX, "SBFX", "11110-110100----0---------------")
//INST(thumb32_BFC, "BFC", "11110-11011011110---------------")
//INST(thumb32_BFI, "BFI", "11110-110110----0---------------")
//INST(thumb32_USAT, "USAT", "11110-111000----0---------------")
//INST(thumb32_USAT16, "USAT16", "11110-111010----0000----00------")
INST(thumb32_USAT16, "USAT16", "111100111010nnnn0000dddd0000iiii")
//INST(thumb32_USAT, "USAT", "11110-111010----0---------------")
//INST(thumb32_UBFX, "UBFX", "11110-111100----0---------------")

View file

@ -6,6 +6,33 @@
#include "frontend/A32/translate/impl/translate_thumb.h"
namespace Dynarmic::A32 {
static IR::U32 Pack2x16To1x32(A32::IREmitter& ir, IR::U32 lo, IR::U32 hi) {
return ir.Or(ir.And(lo, ir.Imm32(0xFFFF)), ir.LogicalShiftLeft(hi, ir.Imm8(16), ir.Imm1(0)).result);
}
static IR::U16 MostSignificantHalf(A32::IREmitter& ir, IR::U32 value) {
return ir.LeastSignificantHalf(ir.LogicalShiftRight(value, ir.Imm8(16), ir.Imm1(0)).result);
}
using SaturationFunction = IR::ResultAndOverflow<IR::U32> (IREmitter::*)(const IR::U32&, size_t);
static bool Saturation16(ThumbTranslatorVisitor& v, Reg n, Reg d, size_t saturate_to, SaturationFunction sat_fn) {
if (d == Reg::PC || n == Reg::PC) {
return v.UnpredictableInstruction();
}
const auto reg_n = v.ir.GetRegister(n);
const auto lo_operand = v.ir.SignExtendHalfToWord(v.ir.LeastSignificantHalf(reg_n));
const auto hi_operand = v.ir.SignExtendHalfToWord(MostSignificantHalf(v.ir, reg_n));
const auto lo_result = (v.ir.*sat_fn)(lo_operand, saturate_to);
const auto hi_result = (v.ir.*sat_fn)(hi_operand, saturate_to);
v.ir.SetRegister(d, Pack2x16To1x32(v.ir, lo_result.result, hi_result.result));
v.ir.OrQFlag(lo_result.overflow);
v.ir.OrQFlag(hi_result.overflow);
return true;
}
bool ThumbTranslatorVisitor::thumb32_MOVT(Imm<1> imm1, Imm<4> imm4, Imm<3> imm3, Reg d, Imm<8> imm8) {
if (d == Reg::PC) {
@ -31,4 +58,12 @@ bool ThumbTranslatorVisitor::thumb32_MOVW_imm(Imm<1> imm1, Imm<4> imm4, Imm<3> i
return true;
}
bool ThumbTranslatorVisitor::thumb32_SSAT16(Reg n, Reg d, Imm<4> sat_imm) {
return Saturation16(*this, n, d, sat_imm.ZeroExtend() + 1, &IREmitter::SignedSaturation);
}
bool ThumbTranslatorVisitor::thumb32_USAT16(Reg n, Reg d, Imm<4> sat_imm) {
return Saturation16(*this, n, d, sat_imm.ZeroExtend(), &IREmitter::UnsignedSaturation);
}
} // namespace Dynarmic::A32

View file

@ -162,6 +162,8 @@ struct ThumbTranslatorVisitor final {
// thumb32 data processing (plain binary immediate) instructions.
bool thumb32_MOVT(Imm<1> imm1, Imm<4> imm4, Imm<3> imm3, Reg d, Imm<8> imm8);
bool thumb32_MOVW_imm(Imm<1> imm1, Imm<4> imm4, Imm<3> imm3, Reg d, Imm<8> imm8);
bool thumb32_SSAT16(Reg n, Reg d, Imm<4> sat_imm);
bool thumb32_USAT16(Reg n, Reg d, Imm<4> sat_imm);
// thumb32 miscellaneous control instructions
bool thumb32_BXJ(Reg m);