src/arch/x86/isa/decoder/one_byte_opcodes.isa:
Give the "MOV" instruction the format of it's arguments. This will likely need to be completely overhauled in the near future.
src/arch/x86/predecoder.cc:
src/arch/x86/predecoder.hh:
Make the predecoder explicitly reset itself rather than counting on it happening naturally.
src/arch/x86/predecoder_tables.cc:
Fix the immediate size table
src/arch/x86/regfile.cc:
nextnpc is bogus
--HG--
extra : convert_revision :
0926701fedaab41817e64bb05410a25174484a5a
0x7: xchg_Ev_Gv();
}
0x11: decode OPCODE_OP_BOTTOM3 {
- 0x0: Inst::MOV(); //mov_Eb_Gb();
- 0x1: Inst::MOV(); //mov_Ev_Gv();
- 0x2: Inst::MOV(); //mov_Gb_Eb();
- 0x3: Inst::MOV(); //mov_Gv_Ev();
- 0x4: Inst::MOV(); //mov_MwRv_Sw();
+ 0x0: Inst::MOV(Eb, Gb);
+ 0x1: Inst::MOV(Ev, Gv);
+ 0x2: Inst::MOV(Gb, Eb);
+ 0x3: Inst::MOV(Gv, Ev);
+ 0x4: mov_MwRv_Sw(); //What to do with this one?
0x5: lea_Gv_M();
0x6: mov_Sw_MwRv();
0x7: group10_Ev(); //Make sure this is Ev
namespace X86ISA
{
+ void Predecoder::reset()
+ {
+ origPC = basePC + offset;
+ DPRINTF(Predecoder, "Setting origPC to %#x\n", origPC);
+ emi.opcode.num = 0;
+
+ immediateCollected = 0;
+ emi.immediate = 0;
+ displacementCollected = 0;
+ emi.displacement = 0;
+
+ emi.modRM = 0;
+ emi.sib = 0;
+ }
+
void Predecoder::process()
{
//This function drives the predecoder state machine.
uint8_t nextByte = getNextByte();
switch(state)
{
+ case ResetState:
+ reset();
+ state = PrefixState;
case PrefixState:
state = doPrefixState(nextByte);
break;
emi.rex = nextByte;
break;
case 0:
- emi.opcode.num = 0;
nextState = OpcodeState;
break;
default:
DPRINTF(Predecoder, "Found opcode %#x.\n", nextByte);
emi.opcode.op = nextByte;
- //Prepare for any immediate/displacement we might need
- immediateCollected = 0;
- emi.immediate = 0;
- displacementCollected = 0;
- emi.displacement = 0;
-
//Figure out the effective operand size. This can be overriden to
//a fixed value at the decoder level.
if(/*FIXME long mode*/1)
if (UsesModRM[emi.opcode.num - 1][nextByte]) {
nextState = ModRMState;
} else {
- //If there's no modRM byte, set it to 0 so we can detect
- //that later.
- emi.modRM = 0;
if(immediateSize) {
nextState = ImmediateState;
} else {
emiIsReady = true;
- nextState = PrefixState;
+ nextState = ResetState;
}
}
}
nextState = ImmediateState;
} else {
emiIsReady = true;
- nextState = PrefixState;
+ nextState = ResetState;
}
//The ModRM byte is consumed no matter what
consumeByte();
nextState = ImmediateState;
} else {
emiIsReady = true;
- nextState = PrefixState;
+ nextState = ResetState;
}
return nextState;
}
nextState = ImmediateState;
} else {
emiIsReady = true;
- nextState = PrefixState;
+ nextState = ResetState;
}
}
else
DPRINTF(Predecoder, "Collected immediate %#x.\n",
emi.immediate);
emiIsReady = true;
- nextState = PrefixState;
+ nextState = ResetState;
}
else
nextState = ImmediateState;
#include "arch/x86/types.hh"
#include "base/bitfield.hh"
+#include "base/misc.hh"
+#include "base/trace.hh"
#include "sim/host.hh"
class ThreadContext;
MachInst fetchChunk;
//The pc of the start of fetchChunk
Addr basePC;
+ //The pc the current instruction started at
+ Addr origPC;
//The offset into fetchChunk of current processing
int offset;
//The extended machine instruction being generated
outOfBytes = true;
}
+ void reset();
+
//State machine state
protected:
//Whether or not we're out of bytes
int immediateCollected;
enum State {
+ ResetState,
PrefixState,
OpcodeState,
ModRMState,
public:
Predecoder(ThreadContext * _tc) :
- tc(_tc), basePC(0), offset(0),
+ tc(_tc), basePC(0), origPC(0), offset(0),
outOfBytes(true), emiIsReady(false),
- state(PrefixState)
+ state(ResetState)
{}
ThreadContext * getTC()
emiIsReady = false;
return emi;
}
+
+ int getInstSize()
+ {
+ DPRINTF(Predecoder,
+ "Calculating the instruction size: "
+ "basePC: %#x offset: %#x origPC: %#x\n",
+ basePC, offset, origPC);
+ return basePC + offset - origPC;
+ }
};
};
// noimm byte word dword qword oword vword zword enter pointer
{0, 1, 2, 4, 8, 16, 2, 2, 3, 4 }, //16 bit
{0, 1, 2, 4, 8, 16, 4, 4, 3, 6 }, //32 bit
- {0, 1, 2, 4, 8, 16, 4, 8, 3, 0 } //64 bit
+ {0, 1, 2, 4, 8, 16, 8, 4, 3, 0 } //64 bit
};
//This table determines the immediate type. The first index is the
Addr RegFile::readNextNPC()
{
- return nextRip + sizeof(MachInst);
+ //There's no way to know how big the -next- instruction will be.
+ return nextRip + 1;
}
void RegFile::setNextNPC(Addr val)