base.isa revision 2135 
1// -*- mode:c++ -*-
2
3////////////////////////////////////////////////////////////////////
4//
5// Base class for MIPS instructions, and some support functions
6//
7
8//Outputs to decoder.hh
9output header {{
10#define R31 31
11
12    /**
13     * Base class for all MIPS static instructions.
14     */
15    class MipsStaticInst : public StaticInst
16    {
17      protected:
18
19        /// Make MipsISA register dependence tags directly visible in
20        /// this class and derived classes.  Maybe these should really
21        /// live here and not in the MipsISA namespace.
22        enum DependenceTags {
23            FP_Base_DepTag = MipsISA::FP_Base_DepTag,
24            Fpcr_DepTag = MipsISA::Fpcr_DepTag,
25            Uniq_DepTag = MipsISA::Uniq_DepTag,
26            IPR_Base_DepTag = MipsISA::IPR_Base_DepTag
27        };
28
29        // Constructor
30        MipsStaticInst(const char *mnem, MachInst _machInst, OpClass __opClass)
31            : StaticInst(mnem, _machInst, __opClass)
32        {
33        }
34
35        /// Print a register name for disassembly given the unique
36        /// dependence tag number (FP or int).
37        void printReg(std::ostream &os, int reg) const;
38
39        std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;
40    };
41
42}};
43
44//Ouputs to decoder.cc
45output decoder {{
46
47    void MipsStaticInst::printReg(std::ostream &os, int reg) const
48    {
49        if (reg < FP_Base_DepTag) {
50            ccprintf(os, "r%d", reg);
51        }
52        else {
53            ccprintf(os, "f%d", reg - FP_Base_DepTag);
54        }
55    }
56
57    std::string MipsStaticInst::generateDisassembly(Addr pc, const SymbolTable *symtab) const
58    {
59        std::stringstream ss;
60
61        ccprintf(ss, "%-10s ", mnemonic);
62
63        // just print the first two source regs... if there's
64        // a third one, it's a read-modify-write dest (Rc),
65        // e.g. for CMOVxx
66        if(_numSrcRegs > 0)
67        {
68            printReg(ss, _srcRegIdx[0]);
69        }
70        if(_numSrcRegs > 1)
71        {
72            ss << ",";
73            printReg(ss, _srcRegIdx[1]);
74        }
75
76        // just print the first dest... if there's a second one,
77        // it's generally implicit
78        if(_numDestRegs > 0)
79        {
80            if(_numSrcRegs > 0)
81                ss << ",";
82            printReg(ss, _destRegIdx[0]);
83        }
84
85        return ss.str();
86    }
87
88}};
89
90