153 lines
5 KiB
C++
153 lines
5 KiB
C++
/* This file is part of the dynarmic project.
|
|
* Copyright (c) 2016 MerryMage
|
|
* This software may be used and distributed according to the terms of the GNU
|
|
* General Public License version 2 or any later version.
|
|
*/
|
|
|
|
#include "backend_x64/block_of_code.h"
|
|
#include "backend_x64/emit_x64.h"
|
|
#include "common/assert.h"
|
|
#include "common/bit_util.h"
|
|
#include "common/common_types.h"
|
|
#include "frontend/ir/basic_block.h"
|
|
#include "frontend/ir/microinstruction.h"
|
|
#include "frontend/ir/opcodes.h"
|
|
|
|
namespace Dynarmic {
|
|
namespace BackendX64 {
|
|
|
|
using namespace Xbyak::util;
|
|
|
|
void EmitX64::EmitSignedSaturatedAdd(EmitContext& ctx, IR::Inst* inst) {
|
|
auto overflow_inst = inst->GetAssociatedPseudoOperation(IR::Opcode::GetOverflowFromOp);
|
|
|
|
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
|
|
|
|
Xbyak::Reg32 result = ctx.reg_alloc.UseScratchGpr(args[0]).cvt32();
|
|
Xbyak::Reg32 addend = ctx.reg_alloc.UseGpr(args[1]).cvt32();
|
|
Xbyak::Reg32 overflow = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
|
|
code->mov(overflow, result);
|
|
code->shr(overflow, 31);
|
|
code->add(overflow, 0x7FFFFFFF);
|
|
// overflow now contains 0x7FFFFFFF if a was positive, or 0x80000000 if a was negative
|
|
code->add(result, addend);
|
|
code->cmovo(result, overflow);
|
|
|
|
if (overflow_inst) {
|
|
code->seto(overflow.cvt8());
|
|
|
|
ctx.reg_alloc.DefineValue(overflow_inst, overflow);
|
|
ctx.EraseInstruction(overflow_inst);
|
|
}
|
|
|
|
ctx.reg_alloc.DefineValue(inst, result);
|
|
}
|
|
|
|
void EmitX64::EmitSignedSaturatedSub(EmitContext& ctx, IR::Inst* inst) {
|
|
auto overflow_inst = inst->GetAssociatedPseudoOperation(IR::Opcode::GetOverflowFromOp);
|
|
|
|
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
|
|
|
|
Xbyak::Reg32 result = ctx.reg_alloc.UseScratchGpr(args[0]).cvt32();
|
|
Xbyak::Reg32 subend = ctx.reg_alloc.UseGpr(args[1]).cvt32();
|
|
Xbyak::Reg32 overflow = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
|
|
code->mov(overflow, result);
|
|
code->shr(overflow, 31);
|
|
code->add(overflow, 0x7FFFFFFF);
|
|
// overflow now contains 0x7FFFFFFF if a was positive, or 0x80000000 if a was negative
|
|
code->sub(result, subend);
|
|
code->cmovo(result, overflow);
|
|
|
|
if (overflow_inst) {
|
|
code->seto(overflow.cvt8());
|
|
|
|
ctx.reg_alloc.DefineValue(overflow_inst, overflow);
|
|
ctx.EraseInstruction(overflow_inst);
|
|
}
|
|
|
|
ctx.reg_alloc.DefineValue(inst, result);
|
|
}
|
|
|
|
void EmitX64::EmitUnsignedSaturation(EmitContext& ctx, IR::Inst* inst) {
|
|
auto overflow_inst = inst->GetAssociatedPseudoOperation(IR::Opcode::GetOverflowFromOp);
|
|
|
|
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
|
|
size_t N = args[1].GetImmediateU8();
|
|
ASSERT(N <= 31);
|
|
|
|
u32 saturated_value = (1u << N) - 1;
|
|
|
|
Xbyak::Reg32 result = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
Xbyak::Reg32 reg_a = ctx.reg_alloc.UseGpr(args[0]).cvt32();
|
|
Xbyak::Reg32 overflow = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
|
|
// Pseudocode: result = clamp(reg_a, 0, saturated_value);
|
|
code->xor_(overflow, overflow);
|
|
code->cmp(reg_a, saturated_value);
|
|
code->mov(result, saturated_value);
|
|
code->cmovle(result, overflow);
|
|
code->cmovbe(result, reg_a);
|
|
|
|
if (overflow_inst) {
|
|
code->seta(overflow.cvt8());
|
|
|
|
ctx.reg_alloc.DefineValue(overflow_inst, overflow);
|
|
ctx.EraseInstruction(overflow_inst);
|
|
}
|
|
|
|
ctx.reg_alloc.DefineValue(inst, result);
|
|
}
|
|
|
|
void EmitX64::EmitSignedSaturation(EmitContext& ctx, IR::Inst* inst) {
|
|
auto overflow_inst = inst->GetAssociatedPseudoOperation(IR::Opcode::GetOverflowFromOp);
|
|
|
|
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
|
|
size_t N = args[1].GetImmediateU8();
|
|
ASSERT(N >= 1 && N <= 32);
|
|
|
|
if (N == 32) {
|
|
if (overflow_inst) {
|
|
auto no_overflow = IR::Value(false);
|
|
overflow_inst->ReplaceUsesWith(no_overflow);
|
|
}
|
|
ctx.reg_alloc.DefineValue(inst, args[0]);
|
|
return;
|
|
}
|
|
|
|
u32 mask = (1u << N) - 1;
|
|
u32 positive_saturated_value = (1u << (N - 1)) - 1;
|
|
u32 negative_saturated_value = 1u << (N - 1);
|
|
u32 sext_negative_satured_value = Common::SignExtend(N, negative_saturated_value);
|
|
|
|
Xbyak::Reg32 result = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
Xbyak::Reg32 reg_a = ctx.reg_alloc.UseGpr(args[0]).cvt32();
|
|
Xbyak::Reg32 overflow = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
Xbyak::Reg32 tmp = ctx.reg_alloc.ScratchGpr().cvt32();
|
|
|
|
// overflow now contains a value between 0 and mask if it was originally between {negative,positive}_saturated_value.
|
|
code->lea(overflow, code->ptr[reg_a.cvt64() + negative_saturated_value]);
|
|
|
|
// Put the appropriate saturated value in result
|
|
code->cmp(reg_a, positive_saturated_value);
|
|
code->mov(tmp, positive_saturated_value);
|
|
code->mov(result, sext_negative_satured_value);
|
|
code->cmovg(result, tmp);
|
|
|
|
// Do the saturation
|
|
code->cmp(overflow, mask);
|
|
code->cmovbe(result, reg_a);
|
|
|
|
if (overflow_inst) {
|
|
code->seta(overflow.cvt8());
|
|
|
|
ctx.reg_alloc.DefineValue(overflow_inst, overflow);
|
|
ctx.EraseInstruction(overflow_inst);
|
|
}
|
|
|
|
ctx.reg_alloc.DefineValue(inst, result);
|
|
}
|
|
|
|
} // namespace BackendX64
|
|
} // namespace Dynarmic
|