BOOL SigFunc(THREADID tid, INT32 sig, CONTEXT *ctxt, BOOL hasHandler, const EXCEPTION_INFO *pExceptInfo, void *dummy)
{
ADDRINT address = PIN_GetContextReg(ctxt, REG_INST_PTR);
cout << "Thread " << tid << ": Tool got signal " << sig << " at PC " << hex << address << dec << "\n";
numSignalsReceived++;
if (numSignalsReceived == (NUM_SEGVS/2))
{
// Invalidate this instruction in code cache so it will be reinstrumented
cout << "invalidating after " << numSignalsReceived << endl;
CODECACHE_InvalidateRange(address, address + 20);
}
return (TRUE); // skip to next instruction
}
BOOL SegvHandler(THREADID, INT32, CONTEXT *ctxt, BOOL, const EXCEPTION_INFO *, void *)
{
ADDRINT address = PIN_GetContextReg(ctxt, REG_INST_PTR);
//fprintf(stderr, "Fault at %p\n",(void*)address);
if (SwizzleRefs.find(address) != SwizzleRefs.end())
{
return true;
}
// The next time we see this address, it requires swizzling
SwizzleRefs.insert(address);
// Invalidate this instruction in code cache so it will be reinstrumented
CODECACHE_InvalidateRange(address, address + 20);
// returning from the signal handler will re-execute the instruction
// this time it will be swizzled
return false;
}
