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#ifndef ARMJIT_REGCACHE_H
#define ARMJIT_REGCACHE_H
#include "ARMJIT.h"
// TODO: replace this in the future
#include "dolphin/BitSet.h"
#include <assert.h>
namespace ARMJIT
{
template <typename T, typename Reg>
class RegisterCache
{
public:
RegisterCache()
{}
RegisterCache(T* compiler, FetchedInstr instrs[], int instrsCount, bool pcAllocatableAsSrc = false)
: Compiler(compiler), Instrs(instrs), InstrsCount(instrsCount)
{
for (int i = 0; i < 16; i++)
Mapping[i] = (Reg)-1;
PCAllocatableAsSrc = ~(pcAllocatableAsSrc
? 0
: (1 << 15));
}
void UnloadRegister(int reg)
{
assert(Mapping[reg] != -1);
if (DirtyRegs & (1 << reg))
Compiler->SaveReg(reg, Mapping[reg]);
DirtyRegs &= ~(1 << reg);
LoadedRegs &= ~(1 << reg);
NativeRegsUsed &= ~(1 << (int)Mapping[reg]);
Mapping[reg] = (Reg)-1;
}
void LoadRegister(int reg, bool loadValue)
{
assert(Mapping[reg] == -1);
for (int i = 0; i < NativeRegsAvailable; i++)
{
Reg nativeReg = NativeRegAllocOrder[i];
if (!(NativeRegsUsed & (1 << nativeReg)))
{
Mapping[reg] = nativeReg;
NativeRegsUsed |= 1 << (int)nativeReg;
LoadedRegs |= 1 << reg;
if (loadValue)
Compiler->LoadReg(reg, nativeReg);
return;
}
}
printf("this is a JIT bug! LoadRegister failed\n");
abort();
}
void PutLiteral(int reg, u32 val)
{
LiteralsLoaded |= (1 << reg);
LiteralValues[reg] = val;
}
void UnloadLiteral(int reg)
{
LiteralsLoaded &= ~(1 << reg);
}
bool IsLiteral(int reg)
{
return LiteralsLoaded & (1 << reg);
}
void PrepareExit()
{
BitSet16 dirtyRegs(DirtyRegs);
for (int reg : dirtyRegs)
Compiler->SaveReg(reg, Mapping[reg]);
}
void Flush()
{
BitSet16 loadedSet(LoadedRegs);
for (int reg : loadedSet)
UnloadRegister(reg);
LiteralsLoaded = 0;
}
void Prepare(bool thumb, int i)
{
FetchedInstr instr = Instrs[i];
if (LoadedRegs & (1 << 15))
UnloadRegister(15);
BitSet16 invalidedLiterals(LiteralsLoaded & instr.Info.DstRegs);
for (int reg : invalidedLiterals)
UnloadLiteral(reg);
u16 futureNeeded = 0;
int ranking[16];
for (int j = 0; j < 16; j++)
ranking[j] = 0;
for (int j = i; j < InstrsCount; j++)
{
BitSet16 regsNeeded((Instrs[j].Info.SrcRegs & ~(1 << 15)) | Instrs[j].Info.DstRegs);
futureNeeded |= regsNeeded.m_val;
regsNeeded &= BitSet16(~Instrs[j].Info.NotStrictlyNeeded);
for (int reg : regsNeeded)
ranking[reg]++;
}
// we'll unload all registers which are never used again
BitSet16 neverNeededAgain(LoadedRegs & ~futureNeeded);
for (int reg : neverNeededAgain)
UnloadRegister(reg);
u16 necessaryRegs = ((instr.Info.SrcRegs & PCAllocatableAsSrc) | instr.Info.DstRegs) & ~instr.Info.NotStrictlyNeeded;
BitSet16 needToBeLoaded(necessaryRegs & ~LoadedRegs);
if (needToBeLoaded != BitSet16(0))
{
int neededCount = needToBeLoaded.Count();
BitSet16 loadedSet(LoadedRegs);
while (loadedSet.Count() + neededCount > NativeRegsAvailable)
{
int leastReg = -1;
int rank = 1000;
for (int reg : loadedSet)
{
if (!((1 << reg) & necessaryRegs) && ranking[reg] < rank)
{
leastReg = reg;
rank = ranking[reg];
}
}
assert(leastReg != -1);
UnloadRegister(leastReg);
loadedSet.m_val = LoadedRegs;
}
// we don't need to load a value which is always going to be overwritten
BitSet16 needValueLoaded(needToBeLoaded);
if (thumb || instr.Cond() >= 0xE)
needValueLoaded = BitSet16(instr.Info.SrcRegs);
for (int reg : needToBeLoaded)
LoadRegister(reg, needValueLoaded[reg]);
}
{
BitSet16 loadedSet(LoadedRegs);
BitSet16 loadRegs(instr.Info.NotStrictlyNeeded & futureNeeded & ~LoadedRegs);
if (loadRegs && loadedSet.Count() < NativeRegsAvailable)
{
int left = NativeRegsAvailable - loadedSet.Count();
for (int reg : loadRegs)
{
if (left-- == 0)
break;
LoadRegister(reg, !(thumb || instr.Cond() >= 0xE) || (1 << reg) & instr.Info.SrcRegs);
}
}
}
DirtyRegs |= (LoadedRegs & instr.Info.DstRegs) & ~(1 << 15);
}
static const Reg NativeRegAllocOrder[];
static const int NativeRegsAvailable;
Reg Mapping[16];
u32 LiteralValues[16];
u16 LiteralsLoaded = 0;
u32 NativeRegsUsed = 0;
u16 LoadedRegs = 0;
u16 DirtyRegs = 0;
u16 PCAllocatableAsSrc = 0;
T* Compiler;
FetchedInstr* Instrs;
int InstrsCount;
};
}
#endif
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