Why does the pin count only three blocks in trace?

Question

I want to list all traces with the blocks they contain, using intel pin. But, as a result, I have a maximum of three blocks in the trace, although there should be more. Tell me, please, why is that so? Thanks in advance!

#include "pin.H"
#include <stdio.h>
using namespace std;

FILE* traceFile;
UINT32 traceNumber = 0;

VOID Trace(TRACE trace, VOID* v)
{    
    UINT32 blockNumber = 0;

    // print trace info
    fprintf(traceFile, "Trace [%d]: %p, number of blocks: %d\n", traceNumber, TRACE_Address(trace), TRACE_NumBbl(trace));
    
    for (BBL bbl = TRACE_BblHead(trace); BBL_Valid(bbl); bbl = BBL_Next(bbl))
    {                
        // print block info
        fprintf(traceFile, "\nBlock [%d]: %p, insts in block: %d\n\n",
            blockNumber, BBL_Address(bbl), BBL_NumIns(bbl));

        // print all insts in block
        for (INS ins = BBL_InsHead(bbl); INS_Valid(ins); ins = INS_Next(ins))
            fprintf(traceFile, "%p: %s\n", INS_Address(ins), INS_Disassemble(ins).c_str());        
        blockNumber++;
    }
    fprintf(traceFile, "\nTrace [%d] end. %s", traceNumber,
        "\n---------------------------------------------------\n\n");
    traceNumber++;
}

void Fini(INT32 code, void* v) { 
    fclose(traceFile);
}

int main(int argc, char* argv[])
{
    traceFile = fopen("itrace.out", "w");
    PIN_InitSymbols();
    PIN_Init(argc, argv);        
    TRACE_AddInstrumentFunction(Trace, 0);    
    PIN_AddFiniFunction(Fini, 0);
    PIN_StartProgram();
    return 0;
}

For example, there are only three blocks here, although I expected to see more:

Trace [4]: 0x7722de32, number of blocks: 3

Block [0]: 0x7722de32, insts in block: 2

0x7722de32: test eax, eax
0x7722de34: jnz 0x77279708

Block [1]: 0x7722de3a, insts in block: 3

0x7722de3a: movzx eax, byte ptr [0x7ffe0384]
0x7722de41: test eax, eax
0x7722de43: jnz 0x7727971d

Block [2]: 0x7722de49, insts in block: 2

0x7722de49: cmp dword ptr [ebp-0x24], ebx
0x7722de4c: jnz 0x7722de5b

Trace [4] end. 
---------------------------------------------------

Shouldn't there be 5 blocks here? Apparently, I don’t understand something about blocks and traces. I didn’t see anywhere in the logs that the number of blocks in traces is more than three, for some reason.

in the debugger I see at least 4 blocks

I want to list all traces with the blocks they contain, using intel pin. But, as a result, I have a maximum of three blocks in the trace, although there should be more. Tell me, please, why is that so? Thanks in advance!

Why does the pin count only three blocks in trace?

0 Answers0