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CPU/NewRec: Speculative execution for mult/div

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This commit is contained in:
Stenzek 2024-02-23 11:57:38 +09:00
parent 175d2a17f7
commit 53c0dc8bbc
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2 changed files with 97 additions and 42 deletions
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120
src/core/cpu_newrec_compiler.cpp
View file

@ -2013,6 +2013,42 @@ void CPU::NewRec::Compiler::Compile_multu_const(CompileFlags cf)
SetConstantReg(Reg::lo, static_cast<u32>(res));
}
void CPU::NewRec::Compiler::MIPSSignedDivide(s32 num, s32 denom, u32* lo, u32* hi)
{
if (denom == 0)
{
// divide by zero
*lo = (num >= 0) ? UINT32_C(0xFFFFFFFF) : UINT32_C(1);
*hi = static_cast<u32>(num);
}
else if (static_cast<u32>(num) == UINT32_C(0x80000000) && denom == -1)
{
// unrepresentable
*lo = UINT32_C(0x80000000);
*hi = 0;
}
else
{
*lo = static_cast<u32>(num / denom);
*hi = static_cast<u32>(num % denom);
}
}
void CPU::NewRec::Compiler::MIPSUnsignedDivide(u32 num, u32 denom, u32* lo, u32* hi)
{
if (denom == 0)
{
// divide by zero
*lo = UINT32_C(0xFFFFFFFF);
*hi = static_cast<u32>(num);
}
else
{
*lo = num / denom;
*hi = num % denom;
}
}
void CPU::NewRec::Compiler::Compile_div_const(CompileFlags cf)
{
DebugAssert(HasConstantReg(cf.MipsS()) && HasConstantReg(cf.MipsT()));
@ -2020,24 +2056,8 @@ void CPU::NewRec::Compiler::Compile_div_const(CompileFlags cf)
const s32 num = GetConstantRegS32(cf.MipsS());
const s32 denom = GetConstantRegS32(cf.MipsT());
s32 lo, hi;
if (denom == 0)
{
// divide by zero
lo = (num >= 0) ? UINT32_C(0xFFFFFFFF) : UINT32_C(1);
hi = static_cast<u32>(num);
}
else if (static_cast<u32>(num) == UINT32_C(0x80000000) && denom == -1)
{
// unrepresentable
lo = UINT32_C(0x80000000);
hi = 0;
}
else
{
lo = num / denom;
hi = num % denom;
}
u32 lo, hi;
MIPSSignedDivide(num, denom, &lo, &hi);
SetConstantReg(Reg::hi, hi);
SetConstantReg(Reg::lo, lo);
@ -2051,18 +2071,7 @@ void CPU::NewRec::Compiler::Compile_divu_const(CompileFlags cf)
const u32 denom = GetConstantRegU32(cf.MipsT());
u32 lo, hi;
if (denom == 0)
{
// divide by zero
lo = UINT32_C(0xFFFFFFFF);
hi = static_cast<u32>(num);
}
else
{
lo = num / denom;
hi = num % denom;
}
MIPSUnsignedDivide(num, denom, &lo, &hi);
SetConstantReg(Reg::hi, hi);
SetConstantReg(Reg::lo, lo);
@ -2520,31 +2529,74 @@ void CPU::NewRec::Compiler::SpecExec_srav()
void CPU::NewRec::Compiler::SpecExec_mult()
{
// TODO
const SpecValue rs = SpecReadReg(inst->r.rs);
const SpecValue rt = SpecReadReg(inst->r.rt);
if (rs.has_value() && rt.has_value())
{
const u64 result =
static_cast<u64>(static_cast<s64>(SignExtend64(rs.value())) * static_cast<s64>(SignExtend64(rt.value())));
SpecWriteReg(Reg::hi, Truncate32(result >> 32));
SpecWriteReg(Reg::lo, Truncate32(result));
}
else
{
SpecInvalidateReg(Reg::hi);
SpecInvalidateReg(Reg::lo);
}
}
void CPU::NewRec::Compiler::SpecExec_multu()
{
// TODO
const SpecValue rs = SpecReadReg(inst->r.rs);
const SpecValue rt = SpecReadReg(inst->r.rt);
if (rs.has_value() && rt.has_value())
{
const u64 result = ZeroExtend64(rs.value()) * SignExtend64(rt.value());
SpecWriteReg(Reg::hi, Truncate32(result >> 32));
SpecWriteReg(Reg::lo, Truncate32(result));
}
else
{
SpecInvalidateReg(Reg::hi);
SpecInvalidateReg(Reg::lo);
}
}
void CPU::NewRec::Compiler::SpecExec_div()
{
// TODO
const SpecValue rs = SpecReadReg(inst->r.rs);
const SpecValue rt = SpecReadReg(inst->r.rt);
if (rs.has_value() && rt.has_value())
{
u32 lo, hi;
MIPSSignedDivide(static_cast<s32>(rs.value()), static_cast<s32>(rt.value()), &lo, &hi);
SpecWriteReg(Reg::hi, hi);
SpecWriteReg(Reg::lo, lo);
}
else
{
SpecInvalidateReg(Reg::hi);
SpecInvalidateReg(Reg::lo);
}
}
void CPU::NewRec::Compiler::SpecExec_divu()
{
// TODO
const SpecValue rs = SpecReadReg(inst->r.rs);
const SpecValue rt = SpecReadReg(inst->r.rt);
if (rs.has_value() && rt.has_value())
{
u32 lo, hi;
MIPSUnsignedDivide(rs.value(), rt.value(), &lo, &hi);
SpecWriteReg(Reg::hi, hi);
SpecWriteReg(Reg::lo, lo);
}
else
{
SpecInvalidateReg(Reg::hi);
SpecInvalidateReg(Reg::lo);
}
}
void CPU::NewRec::Compiler::SpecExec_add()
{

3
src/core/cpu_newrec_compiler.h
View file

@ -375,6 +375,9 @@ protected:
static u32* GetCop0RegPtr(Cop0Reg reg);
static u32 GetCop0RegWriteMask(Cop0Reg reg);
static void MIPSSignedDivide(s32 num, s32 denom, u32* lo, u32* hi);
static void MIPSUnsignedDivide(u32 num, u32 denom, u32* lo, u32* hi);
void Compile_mfc0(CompileFlags cf);
virtual void Compile_mtc0(CompileFlags cf) = 0;
virtual void Compile_rfe(CompileFlags cf) = 0;