xref: /gem5/src/arch/arm/isa/formats/pred.isa

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

// Copyright (c) 2010 ARM Limited
// All rights reserved
//
// The license below extends only to copyright in the software and shall
// not be construed as granting a license to any other intellectual
// property including but not limited to intellectual property relating
// to a hardware implementation of the functionality of the software
// licensed hereunder.  You may use the software subject to the license
// terms below provided that you ensure that this notice is replicated
// unmodified and in its entirety in all distributions of the software,
// modified or unmodified, in source code or in binary form.
//
// Copyright (c) 2007-2008 The Florida State University
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Stephen Hines

let {{
 
     calcCcCode = '''
        if (%(canOverflow)s){
           cprintf("canOverflow: %%d\\n", Rd < resTemp);
           CpsrQ = (Rd < resTemp) ? 1 << 27 : 0;
        } else {
            uint16_t _ic, _iv, _iz, _in;
            _in = (resTemp >> %(negBit)d) & 1;
            _iz = (resTemp == 0);
            _iv = %(ivValue)s & 1;
            _ic = %(icValue)s & 1;
            
            CondCodesNZ =  (_in << 1) | (_iz);
            CondCodesC  =  _ic;
            CondCodesV  =  _iv;

            DPRINTF(Arm, "in = %%d\\n", _in);
            DPRINTF(Arm, "iz = %%d\\n", _iz);
            DPRINTF(Arm, "ic = %%d\\n", _ic);
            DPRINTF(Arm, "iv = %%d\\n", _iv);
        }
        '''
}};

let {{
    def getCcCode(flagtype):
        icReg = icImm = iv = ''
        negBit = 31
        canOverflow = 'false'

        if flagtype == "none":
            icReg = icImm = 'CondCodesC'
            iv = 'CondCodesV'
        elif flagtype == "llbit":
            icReg = icImm = 'CondCodesC'
            iv = 'CondCodesV'
            negBit = 63
        elif flagtype == "overflow":
            canOverflow = "true" 
            icReg = icImm = iv = '0'
        elif flagtype == "add":
            icReg = icImm = 'findCarry(32, resTemp, Rn, op2)'
            iv = 'findOverflow(32, resTemp, Rn, op2)'
        elif flagtype == "sub":
            icReg = icImm ='findCarry(32, resTemp, Rn, ~op2)'
            iv = 'findOverflow(32, resTemp, Rn, ~op2)'
        elif flagtype == "rsb":
            icReg = icImm = 'findCarry(32, resTemp, op2, ~Rn)'
            iv = 'findOverflow(32, resTemp, op2, ~Rn)'
        else:
            icReg = 'shift_carry_rs(Rm, Rs<7:0>, shift, CondCodesC)'
            icImm = 'shift_carry_imm(Rm, shift_size, shift, CondCodesC)'
            iv = 'CondCodesV'
        return (calcCcCode % {"icValue" : icReg, 
                              "ivValue" : iv, 
                              "negBit" : negBit,
                              "canOverflow" : canOverflow },
               calcCcCode % {"icValue" : icImm, 
                              "ivValue" : iv, 
                              "negBit" : negBit,
                              "canOverflow" : canOverflow })

    def getImmCcCode(flagtype):
        ivValue = icValue = ''
        negBit = 31
        canOverflow = 'false'
        if flagtype == "none":
            icValue = 'CondCodesC'
            ivValue = 'CondCodesV'
        elif flagtype == "llbit":
            icValue = 'CondCodesC'
            ivValue = 'CondCodesV'
            negBit = 63
        elif flagtype == "overflow":
            icVaule = ivValue = '0'
            canOverflow = "true" 
        elif flagtype == "add":
            icValue = 'findCarry(32, resTemp, Rn, rotated_imm)'
            ivValue = 'findOverflow(32, resTemp, Rn, rotated_imm)'
        elif flagtype == "sub":
            icValue = 'findCarry(32, resTemp, Rn, ~rotated_imm)'
            ivValue = 'findOverflow(32, resTemp, Rn, ~rotated_imm)'
        elif flagtype == "rsb":
            icValue = 'findCarry(32, resTemp, rotated_imm, ~Rn)'
            ivValue = 'findOverflow(32, resTemp, rotated_imm, ~Rn)'
        elif flagtype == "modImm":
            icValue = 'rotated_carry'
            ivValue = 'CondCodesV'
        else:
            icValue = '(rotate ? rotated_carry:CondCodesC)'
            ivValue = 'CondCodesV'
        return calcCcCode % vars()
}};

def format DataOp(code, flagtype = logic) {{
    (regCcCode, immCcCode) = getCcCode(flagtype)
    regCode = '''uint32_t op2 = shift_rm_rs(Rm, Rs<7:0>,
                                            shift, CondCodesC);
                 op2 = op2;''' + code
    immCode = '''uint32_t op2 = shift_rm_imm(Rm, shift_size,
                                             shift, CondCodesC);
                 op2 = op2;''' + code
    regIop = InstObjParams(name, Name, 'PredIntOp',
                           {"code": regCode,
                            "predicate_test": predicateTest})
    immIop = InstObjParams(name, Name + "Imm", 'PredIntOp',
                           {"code": immCode,
                            "predicate_test": predicateTest})
    regCcIop = InstObjParams(name, Name + "Cc", 'PredIntOp',
                             {"code": regCode + regCcCode,
                              "predicate_test": condPredicateTest})
    immCcIop = InstObjParams(name, Name + "ImmCc", 'PredIntOp',
                             {"code": immCode + immCcCode,
                              "predicate_test": condPredicateTest})
    header_output = BasicDeclare.subst(regIop) + \
                    BasicDeclare.subst(immIop) + \
                    BasicDeclare.subst(regCcIop) + \
                    BasicDeclare.subst(immCcIop)
    decoder_output = BasicConstructor.subst(regIop) + \
                     BasicConstructor.subst(immIop) + \
                     BasicConstructor.subst(regCcIop) + \
                     BasicConstructor.subst(immCcIop)
    exec_output = PredOpExecute.subst(regIop) + \
                  PredOpExecute.subst(immIop) + \
                  PredOpExecute.subst(regCcIop) + \
                  PredOpExecute.subst(immCcIop)
    decode_block = DataDecode.subst(regIop)
}};

def format DataImmOp(code, flagtype = logic) {{
    code += "resTemp = resTemp;"
    iop = InstObjParams(name, Name, 'PredImmOp',
                        {"code": code,
                         "predicate_test": predicateTest})
    ccIop = InstObjParams(name, Name + "Cc", 'PredImmOp',
                          {"code": code + getImmCcCode(flagtype),
                           "predicate_test": condPredicateTest})
    header_output = BasicDeclare.subst(iop) + \
                    BasicDeclare.subst(ccIop)
    decoder_output = BasicConstructor.subst(iop) + \
                     BasicConstructor.subst(ccIop)
    exec_output = PredOpExecute.subst(iop) + \
                  PredOpExecute.subst(ccIop)
    decode_block = DataImmDecode.subst(iop)
}};

def format PredOp(code, *opt_flags) {{
    iop = InstObjParams(name, Name, 'PredOp',
                        {"code": code,
                         "predicate_test": predicateTest},
                        opt_flags)
    header_output = BasicDeclare.subst(iop)
    decoder_output = BasicConstructor.subst(iop)
    decode_block = BasicDecode.subst(iop)
    exec_output = PredOpExecute.subst(iop)
}};

def format PredImmOp(code, *opt_flags) {{
    iop = InstObjParams(name, Name, 'PredImmOp',
                        {"code": code,
                         "predicate_test": predicateTest},
                        opt_flags)
    header_output = BasicDeclare.subst(iop)
    decoder_output = BasicConstructor.subst(iop)
    decode_block = BasicDecode.subst(iop)
    exec_output = PredOpExecute.subst(iop)
}};