benchmarks/bench-branch-link.cc

// Copyright 2015, ARM Limited
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#include "vixl/a64/macro-assembler-a64.h"
#include "vixl/a64/instructions-a64.h"
#include "vixl/globals.h"

using namespace vixl;

static const int kDefaultInstructionCount = 100000;

// Bind many branches to the same label, like bench-branch.cc but with a single
// label. This stresses the label-linking mechanisms.
int main(int argc, char* argv[]) {
  int instructions = 0;

  switch (argc) {
    case 1:
      instructions = kDefaultInstructionCount;
      break;
    case 2:
      instructions = atoi(argv[1]);
      break;
    default:
      printf("Usage: %s [#instructions]\n", argv[0]);
      exit(1);
  }

  MacroAssembler masm(instructions * kInstructionSize);
  InstructionAccurateScope scope(&masm, instructions);

#define __ masm.

  Label target;
  for (int i = 0; i < instructions; i++) {
    __ b(&target);
  }
  __ bind(&target);

  masm.FinalizeCode();

  return 0;
}