/*
 * Copyright 2002-2019 Intel Corporation.
 * 
 * This software is provided to you as Sample Source Code as defined in the accompanying
 * End User License Agreement for the Intel(R) Software Development Products ("Agreement")
 * section 1.L.
 * 
 * This software and the related documents are provided as is, with no express or implied
 * warranties, other than those that are expressly stated in the License.
 */

/*! @file
Pin Tool for testing the correctness of INS_MemoryDisplacement(INS ins).
INS_MemoryDisplacement computes the memory displacement, which is a sign number. 
Tested only on 64 Linux architecture.
When running the tool with the application: "memory_displacment_app", the output, which is the displacement value, should be -24.
When running the application natively( without the tool), the output, which is the displacement value, should be 4.
*/


#include "pin.H"
#include <string.h>
#include <iostream>
#include <fstream>
using std::string;
using std::ios;
using std::cerr;
using std::ofstream;
using std::endl;
using std::cout;



/* ===================================================================== */
//  Commandline Switches 
/* ===================================================================== */

KNOB<string> KnobOutputFile(KNOB_MODE_WRITEONCE, "pintool",
	"o", "w_malloctrace.out", "specify trace file name");

/* ===================================================================== */
// Finals
/* ===================================================================== */

#if defined(TARGET_MAC)
#define NEG_DISP "_neg_disp"
#else
#define NEG_DISP "neg_disp"
#endif


/* ================================================================== */
// Global variables 
/* ================================================================== */

ADDRDELTA disp;// hold memory displacement value of the first instruction of the instrumented function. 

/* ===================================================================== */
// Instrumentation callbacks
/* ===================================================================== */

VOID ImageLoad(IMG img, VOID *v) { // Pin callback. Registered by IMG_AddInstrumentFunction
	// Instrument the neg_disp () function which resides in memory_displacement_app.s 
	
		// Find the negDispRtn() function.
		RTN negDispRtn = RTN_FindByName(img, NEG_DISP);
		if (RTN_Valid(negDispRtn))
		{
			RTN_Open(negDispRtn);
			INS ins;
			ins = RTN_InsHead(negDispRtn);// First instruction of negDispRtn
			if(INS_Valid(ins)){
					disp = INS_MemoryDisplacement(ins);			
			}			
			RTN_Close(negDispRtn);
		}	
}

/*
 * Print out the displacement of the first instruction of the function: "neg_disp()".
 * When running this tool with the application:"memory_displacement_app", should print -24
 * This function is called when the application exits.
 * @param[in]   code            exit code of the application
 * @param[in]   v               value specified by the tool in the 
 *                              PIN_AddFiniFunction function cal
 */

VOID Fini(INT32 code, VOID *v)
{  
	// Write to a file 
	ofstream OutFile;
	OutFile.open(KnobOutputFile.Value().c_str());
	OutFile.setf(ios::showbase);
	cout<<disp<<endl;
	OutFile.close();
}



/* ===================================================================== */
// Utilities
/* ===================================================================== */

/*
 *  Print out help message.
 */

INT32 Usage()
{
	cerr << "This tool check the correctness of INS_MemoryDisplacement(INS ins) function, which return the displacement as a sign number" << endl;

	//Knobs automate the parsing and management of command line switches. A command line contains switches for Pin, the tool, and the application. The knobs parsing code understands how to separate them. 
	cerr << KNOB_BASE::StringKnobSummary() << endl; //   Print out a summary of all the knobs declare

	return -1;
}


/*
 * The main procedure of the tool.
 * This function is called when the application image is loaded but not yet started.
 * @param[in]   argc            total number of elements in the argv array
 * @param[in]   argv            array of command line arguments, 
 *                              including pin -t <toolname> -- ...
 */

int main(int argc, char *argv[])
{
	PIN_InitSymbols();
	
	// Initialize PIN library.
	if( PIN_Init(argc,argv) )
	{
		return Usage();
	}		
	IMG_AddInstrumentFunction(ImageLoad, 0);

	// Register function to be called when the application exits
	PIN_AddFiniFunction(Fini, 0);

	// Start the program, never returns
	PIN_StartProgram(); 
	return 0;
}