gem5/arch/mips/isa/formats/noop.isa
Korey Sewell 6547e8882b Minor Sconscript edit ... mips decoder changes ... initialize NNPC and output fault name in simple cpu
SConscript:
    Separate Alpha EIO from syscall building for other architectures
arch/isa_specific.hh:
    change MIPS constant to 34k
arch/mips/isa/decoder.isa:
    Allow sll,ssnop,nop, and ehb to be determined through decoder using
    the different types of default cases
arch/mips/isa/formats/branch.isa:
    Delete debug code
arch/mips/isa/formats/noop.isa:
    add a Nop format
arch/mips/isa_traits.hh:
    use constants instead of enums
arch/mips/process.cc:
    point to the correct header file
cpu/simple/cpu.cc:
    Output the actual fault name
sim/process.cc:
    Inititalize NNPC

--HG--
extra : convert_revision : adb0026dfad25b14c98fb03c98bfe9c681bba6f8
2006-03-14 18:28:51 -05:00

95 lines
2.3 KiB
C++

// -*- mode:c++ -*-
////////////////////////////////////////////////////////////////////
//
// Nop
//
output header {{
/**
* Static instruction class for no-ops. This is a leaf class.
*/
class Nop : public MipsStaticInst
{
/// Disassembly of original instruction.
const std::string originalDisassembly;
public:
/// Constructor
Nop(const std::string _originalDisassembly, MachInst _machInst)
: MipsStaticInst("nop", _machInst, No_OpClass),
originalDisassembly(_originalDisassembly)
{
flags[IsNop] = true;
}
~Nop() { }
std::string
generateDisassembly(Addr pc, const SymbolTable *symtab) const;
%(BasicExecDeclare)s
};
}};
output decoder {{
std::string Nop::generateDisassembly(Addr pc,
const SymbolTable *symtab) const
{
#ifdef SS_COMPATIBLE_DISASSEMBLY
return originalDisassembly;
#else
return csprintf("%-10s (%s)", "nop", originalDisassembly);
#endif
}
/// Helper function for decoding nops. Substitute Nop object
/// for original inst passed in as arg (and delete latter).
inline
MipsStaticInst *
makeNop(MipsStaticInst *inst)
{
MipsStaticInst *nop = new Nop(inst->disassemble(0), inst->machInst);
delete inst;
return nop;
}
}};
output exec {{
Fault
Nop::execute(%(CPU_exec_context)s *, Trace::InstRecord *) const
{
return NoFault;
}
}};
// integer & FP operate instructions use RT as dest, so check for
// RT == 0 to detect nops
def template OperateNopCheckDecode {{
{
MipsStaticInst *i = new %(class_name)s(machInst);
//if (RD == 0) {
// i = makeNop(i);
//}
return i;
}
}};
// Like BasicOperate format, but generates NOP if RC/FC == 31
def format BasicOperateWithNopCheck(code, *opt_args) {{
iop = InstObjParams(name, Name, 'MipsStaticInst', CodeBlock(code),
opt_args)
header_output = BasicDeclare.subst(iop)
decoder_output = BasicConstructor.subst(iop)
decode_block = OperateNopCheckDecode.subst(iop)
exec_output = BasicExecute.subst(iop)
}};
def format Nop() {{
decode_block = 'return new Nop(\"sll r0,r0,0\",machInst);\n'
}};