xref: /external/vixl/benchmarks/aarch64/bench-branch-link.cc

// Copyright 2015, VIXL authors
// 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 ARM Limited 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 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 COPYRIGHT OWNER OR 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.

#include <sys/time.h>
#include "globals-vixl.h"

#include "aarch64/instructions-aarch64.h"
#include "aarch64/macro-assembler-aarch64.h"

using namespace vixl;
using namespace vixl::aarch64;

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);
  }

  timeval start;
  gettimeofday(&start, NULL);
  MacroAssembler masm(instructions * kInstructionSize);
  ExactAssemblyScope scope(&masm, instructions * kInstructionSize);

#define __ masm.

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

  masm.FinalizeCode();

  timeval end;
  gettimeofday(&end, NULL);
  double delta = (end.tv_sec - start.tv_sec) +
                 static_cast<double>(end.tv_usec - start.tv_usec) / 1000000;
  printf("A64: time for %d instructions: %gs\n", instructions, delta);

  return 0;
}