//---------------------------------------------------------------------------//
//  1100101 |_ mov #0, r4         __                                         //
//     11   |_ <0xb380 %5c4>     / _|_ _____ ___                             //
//     0110 |_ 3.50 -> 3.60     |  _\ \ / _ (_-<                             //
//          |_ base# + offset   |_| /_\_\___/__/                             //
//---------------------------------------------------------------------------//

#include <fxos/passes/syscall.h>

namespace FxOS {

SyscallPass::SyscallPass(Disassembly &disasm, OS *os):
    InstructionPass(disasm), m_os {os}
{
}

bool SyscallPass::analyzeInstruction(uint32_t pc, Instruction &ci)
{
    /* Nothing to do if no syscall table is provided! */
    if(!m_os)
        return true;

    (void)pc;

    AsmInstruction const *i = ci.inst;
    if(!i)
        return true;

    for(size_t n = 0; n < i->arg_count; n++) {
        AsmArgument const &arg = i->args[n];
        Argument &a = ci.args[n];

        bool eligible = false;
        uint32_t address;

        if(arg.kind == AsmArgument::PcRel && a.value
            && RelConstDomain().is_constant(a.value)) {
            eligible = true;
            address = RelConstDomain().constant_value(a.value);
        }
        if(arg.kind == AsmArgument::PcJump && a.location
            && RelConstDomain().is_constant(a.location)) {
            eligible = true;
            address = RelConstDomain().constant_value(a.location);
        }

        if(eligible) {
            int sid = m_os->find_syscall(address);
            if(sid >= 0)
                a.syscall_id = sid;
        }
    }

    return true;
}

} /* namespace FxOS */