gem5/arch/mips/isa/formats/int.isa

// -*- mode:c++ -*-

////////////////////////////////////////////////////////////////////
//
// Integer operate instructions
//

//Outputs to decoder.hh
output header {{
#include <iostream>
    using namespace std;
        /**
         * Base class for integer operations.
         */
        class IntOp : public MipsStaticInst
        {
                protected:

                /// Constructor
                IntOp(const char *mnem, MachInst _machInst, OpClass __opClass) :
                                MipsStaticInst(mnem, _machInst, __opClass)
                {
                }

                std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;
        };

        class IntImmOp : public MipsStaticInst
        {
                protected:

                int16_t imm;
                int32_t sextImm;
                uint32_t zextImm;

                /// Constructor
                IntImmOp(const char *mnem, MachInst _machInst, OpClass __opClass) :
                    MipsStaticInst(mnem, _machInst, __opClass),imm(INTIMM),
                    sextImm(INTIMM),zextImm(0x0000FFFF & INTIMM)
                {
                    //If Bit 15 is 1 then Sign Extend
                    int32_t temp = sextImm & 0x00008000;
                    if (temp > 0 && mnemonic != "lui") {
                        sextImm |= 0xFFFF0000;
                    }
                }

                std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;


        };

}};

//Outputs to decoder.cc
output decoder {{
        std::string IntOp::generateDisassembly(Addr pc, const SymbolTable *symtab) const
        {
            std::stringstream ss;

            ccprintf(ss, "%-10s ", mnemonic);

            // just print the first dest... if there's a second one,
            // it's generally implicit
            if (_numDestRegs > 0) {
                printReg(ss, _destRegIdx[0]);
                ss << ",";
            }

            // just print the first two source regs... if there's
            // a third one, it's a read-modify-write dest (Rc),
            // e.g. for CMOVxx
            if (_numSrcRegs > 0) {
                printReg(ss, _srcRegIdx[0]);
            }

            if (_numSrcRegs > 1) {
                ss << ",";
                printReg(ss, _srcRegIdx[1]);
            }

            return ss.str();
        }

        std::string IntImmOp::generateDisassembly(Addr pc, const SymbolTable *symtab) const
        {
            std::stringstream ss;

            ccprintf(ss, "%-10s ", mnemonic);

            if (_numDestRegs > 0) {
                printReg(ss, _destRegIdx[0]);
            }

            ss << ",";

            if (_numSrcRegs > 0) {
                printReg(ss, _srcRegIdx[0]);
                ss << ",";
            }

            if( mnemonic == "lui")
                ccprintf(ss, "%08p ", sextImm);
            else
                ss << (int) sextImm;

            return ss.str();
        }

}};

//Used by decoder.isa
def format IntOp(code, *opt_flags) {{
        orig_code = code
        cblk = CodeBlock(code)

        # Figure out if we are creating a IntImmOp or a IntOp
        # by looking at the instruction name
        iop = InstObjParams(name, Name, 'IntOp', cblk, opt_flags)
        strlen = len(name)
        if name[strlen-1] == 'i' or name[strlen-2:] == 'iu':
            iop = InstObjParams(name, Name, 'IntImmOp', cblk, opt_flags)

        header_output = BasicDeclare.subst(iop)
        decoder_output = BasicConstructor.subst(iop)
        decode_block = OperateNopCheckDecode.subst(iop)
        exec_output = BasicExecute.subst(iop)
}};