fxos/lib/passes/syscall.cpp

58 lines
1.7 KiB
C++

//---------------------------------------------------------------------------//
// 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 */