/*BEGIN_LEGAL 
Intel Open Source License 

Copyright (c) 2002-2014 Intel Corporation. All rights reserved.
 
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.  Redistributions
in binary form must reproduce the above copyright notice, this list of
conditions and the following disclaimer in the documentation and/or
other materials provided with the distribution.  Neither the name of
the Intel Corporation nor the names of its contributors may be used to
endorse or promote products derived from this software without
specific prior written permission.
 
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE INTEL OR
ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
END_LEGAL */
/* ===================================================================== */
/*
  @ORIGINAL_AUTHOR: S. Bharadwaj Yadavalli
*/

/* ===================================================================== */
/*! @file
 *  This file contains a test for correctness of the size of memory read
    for cmp instructions with repeat string operation prefix.
    (As well as a number of other tests for our handling of REPped string
    operations).
 */

#include <iostream>
#include <fstream>
#include <string.h>
#ifdef TARGET_LINUX
# include <unistd.h>
#endif
#include "pin.H"

/* ===================================================================== */
/* Global Variables */
/* ===================================================================== */

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

LOCALVAR std::ofstream out;

KNOB<string> KnobOutputFile(KNOB_MODE_WRITEONCE,         "pintool",
    "o", "repcmpsz_tool.out", "Output file");


/* ===================================================================== */

INT32 Usage()
{
    cerr <<
        "This tool prints out the size of memory reads done by two cmp \n"
        "instructions with repeat string operation prefix.\n"
        "\n";

    cerr << KNOB_BASE::StringKnobSummary();

    cerr << endl;

    return -1;
}

/* ===================================================================== */
VOID printSz(UINT32 sz, ADDRINT addr, UINT32 executing, ADDRINT count)
{
    string ex = (executing ? " [TRUE]" : " [FALSE]");
    out << "Read size : " << dec << sz << " %ecx " << dec << count << ex << endl;
}

VOID printCntVal(UINT32 val)
{
    out << "After Count : " << dec << val << endl;
}

VOID printSzPredicated(UINT32 sz, ADDRINT addr, UINT32 executing, ADDRINT count)
{
    out << "Predicated ";
    printSz(sz, addr, executing, count);
}

VOID printCntValPredicated(UINT32 val)
{
    out << "Predicated ";
    printCntVal(val);
}

// Check that IF/THEN is working right, and that multiple AFTER instrumentation works as it should.
LOCALVAR UINT32 icountBits[10];
LOCALVAR UINT32 icount[2];

UINT32 predicate(UINT32 bitNo, ADDRINT ip)
{
    UINT32 ic = icount[0];

    // out << hex << ip << " " << dec << ic << " Testing bit " << dec << bitNo << 
    //     " returns " << ((ic & (1<<bitNo)) != 0) << endl;

    return (ic & (1<<bitNo)) != 0;
}

VOID addCount(UINT32 bitNo)
{
    // out << "Adding one for " << dec << bitNo << endl;
    icountBits[bitNo] += 1;
}

void countInst(UINT32 where)
{
    // out << (where ? "AFTER" : "BEFORE") << " adding one to count" << endl;
    icount[where]++;
}

/* ===================================================================== */
#define STRINGIZE(v) #v

/* Information for each thread. */
class threadState
{
public:
    UINT32    iCount;
    CONTEXT   context;
};

static threadState threadStates[32];

/************************************************************************/

# define REGENTRY(n) { REG_##n, STRINGIZE(n) }

// Table of registers to check and display
static const struct 
{
    REG regnum;
    const char * name;
} checkedRegisters[] = {
    REGENTRY(EFLAGS),
    REGENTRY(EAX),
    REGENTRY(EBX),
    REGENTRY(ECX),
    REGENTRY(EDX),
    REGENTRY(EBP),
    REGENTRY(ESP),
    REGENTRY(EDI),
    REGENTRY(ESI)
};

static VOID printRegisterDiffs(THREADID tid, CONTEXT *ctx, UINT32 where)
{    
    threadState * s = &threadStates[tid];
    UINT32 seqNo    = s->iCount;
    CONTEXT * savedCtx = &s->context;

    // Save the context if this was the first instruction
    if (seqNo == 0)
        PIN_SaveContext(ctx, savedCtx);
    else
    {
        for (UINT32 i=0; i<sizeof(checkedRegisters)/sizeof(checkedRegisters[0]); i++)
        {
            REG r = checkedRegisters[i].regnum;
            ADDRINT newValue = PIN_GetContextReg(ctx, r);

            if (PIN_GetContextReg(savedCtx, r) != newValue)
            {
                if (where != 0)
                {
                    out << "*** Instrumentation (" << dec << where << ") caused a change ";
                }
                out << dec << seqNo << ": " << checkedRegisters[i].name << " = " << hex << UINT32(newValue) << endl;
                PIN_SetContextReg(savedCtx, r, newValue);
            }
        }
    }
}

/* Check that Pin gets IARG_FIRST_REP_ITERATION right on the very first REPped string op.
 * (This tests that the initialization of REG_INST_OUTSIDE_REP in the spill area is
 * correct).
 */
static BOOL firstRepOfAll = TRUE;

static ADDRINT firstTime()
{
    return firstRepOfAll;
}

static VOID checkFirstRep (BOOL first)
{
    if (!first)
    {
        out << "*** First REPped instruction had first iteration flag wrong" << endl;
        out.close();
        _exit(1);
    }
    else
    {
        out << "FirstREPped instruction had correct first iteration flag" << endl;
    }
    firstRepOfAll = FALSE;
}

static UINT32 repStarts = 0;
static UINT32 repIterations = 0;
static UINT32 repZeros = 0;

static VOID countReps(BOOL firsttime, BOOL executing)
{
    repStarts += firsttime ? 1 : 0;
    repIterations += executing ? 1 : 0;
    repZeros += (firsttime && !executing) ? 1 : 0;
}

static VOID printCounts()
{
    out << "REP starts     " << repStarts << endl;
    out << "REP iterations " << repIterations << endl;
    out << "REP zeros      " << repZeros << endl;
}

/* ===================================================================== */
static BOOL instrumenting = FALSE;

VOID Instruction(INS ins, VOID *v)
{
    UINT32 where = 0;

    if (INS_Opcode(ins) == XED_ICLASS_FNOP)
    {
        instrumenting = !instrumenting;
    }

    if (!instrumenting)
        return;
    
    INS_InsertCall(ins, IPOINT_BEFORE, (AFUNPTR)printRegisterDiffs,
                   IARG_THREAD_ID,
                   IARG_CONTEXT,
                   IARG_UINT32, where++,
                   IARG_END);

    // Find string ops only.
    if (INS_IsStringop(ins))
    {
        for (UINT32 bit =0; bit < 5; bit++)
        {
            INS_InsertIfCall (ins, IPOINT_AFTER, (AFUNPTR)predicate, IARG_UINT32, bit, IARG_INST_PTR, IARG_END);
            INS_InsertThenCall (ins, IPOINT_AFTER, (AFUNPTR)addCount,IARG_UINT32, bit,  IARG_END);
        }

        INS_InsertCall(ins, IPOINT_BEFORE, (AFUNPTR)printRegisterDiffs,
                       IARG_THREAD_ID,
                       IARG_CONTEXT,
                       IARG_UINT32, where++,
                       IARG_END);

        INS_InsertCall (ins, IPOINT_BEFORE, (AFUNPTR)countInst, IARG_UINT32, 0, IARG_END);
        INS_InsertCall (ins, IPOINT_AFTER, (AFUNPTR)countInst,  IARG_UINT32, 1, IARG_END);

        INS_InsertCall(ins, IPOINT_BEFORE, (AFUNPTR)printRegisterDiffs,
                       IARG_THREAD_ID,
                       IARG_CONTEXT,
                       IARG_UINT32, where++,
                       IARG_END);

        INS_InsertCall(
            ins, IPOINT_BEFORE, (AFUNPTR) printSz,
            IARG_MEMORYREAD_SIZE, IARG_INST_PTR,
            IARG_EXECUTING,
            IARG_REG_VALUE, REG_ECX,
            IARG_END);

        INS_InsertCall(
            ins, IPOINT_AFTER, (AFUNPTR) printCntVal,
            IARG_REG_VALUE,REG_ECX,
            IARG_END);

        INS_InsertCall(ins, IPOINT_BEFORE, (AFUNPTR)printRegisterDiffs,
                       IARG_THREAD_ID,
                       IARG_CONTEXT,
                       IARG_UINT32, where++,
                       IARG_END);

        INS_InsertPredicatedCall(
            ins, IPOINT_BEFORE, (AFUNPTR) printSzPredicated,
            IARG_MEMORYREAD_SIZE, IARG_INST_PTR,
            IARG_EXECUTING,
            IARG_REG_VALUE, REG_ECX,
            IARG_END);

        INS_InsertPredicatedCall(
            ins, IPOINT_AFTER, (AFUNPTR) printCntValPredicated,
            IARG_REG_VALUE,REG_ECX,
            IARG_END);

        INS_InsertCall(ins, IPOINT_BEFORE, (AFUNPTR)printRegisterDiffs,
                       IARG_THREAD_ID,
                       IARG_CONTEXT,
                       IARG_UINT32, where++,
                       IARG_END);

        if (INS_HasRealRep(ins))
        {
            INS_InsertIfCall(ins, IPOINT_BEFORE, (AFUNPTR)firstTime, IARG_END);
            INS_InsertThenCall(ins, IPOINT_BEFORE, (AFUNPTR)checkFirstRep, IARG_FIRST_REP_ITERATION, IARG_END);

            INS_InsertCall (ins, IPOINT_BEFORE, (AFUNPTR)countReps, IARG_FIRST_REP_ITERATION, IARG_EXECUTING, IARG_END);
        }
    }
}

/* ===================================================================== */

VOID Fini(INT32 code, VOID *v)
{
    UINT32 status = 0;
    if (icount[0] != icount[1])
    {
        out << "***Mismatch in total instructions : Before " << dec << icount[0] << 
            " After " << dec << icount[1] << endl;    
        status = 1;
    }

    UINT32 expectedCounts[5];
    for (UINT32 i=0; i<5; i++)
        expectedCounts[i] = 0;

    for (UINT32 j=0; j<=icount[0]; j++)
    {
        for (UINT32 i=0; i<5; i++)
        {
            if (j & (1<<i))
            {
                expectedCounts[i]++;
            }
        }
    }

    for (UINT32 i=0; i<5; i++)
    {
        if (icountBits[i] != expectedCounts[i])
        {
            out << "*** Bit counts failed : " << dec << i << " expected " << expectedCounts[i] << 
                " see " <<icountBits[i] << endl;
        }
    }


    printCounts();

    out.close();
    _exit(status);
}

/* ===================================================================== */

int main(int argc, char *argv[])
{
    if( PIN_Init(argc,argv) )
    {
        return Usage();
    }
    
    string filename =  KnobOutputFile.Value();
    
    // Do this before we activate controllers
    out.open(filename.c_str());

    INS_AddInstrumentFunction(Instruction, 0);
    PIN_AddFiniFunction(Fini, 0);

    // Never returns
    PIN_StartProgram();
    
    return 0;
}

/* ===================================================================== */
/* eof */
/* ===================================================================== */
