benchmarks/aarch64/bench-branch-link.cc

// Copyright 2019, VIXL authors
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#include "bench-utils.h"
#include "globals-vixl.h"

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

using namespace vixl;
using namespace vixl::aarch64;

// 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[]) {
  BenchCLI cli(argc, argv);
  if (cli.ShouldExitEarly()) return cli.GetExitCode();

  const size_t buffer_size = 256 * KBytes;
  const size_t buffer_instruction_count = buffer_size / kInstructionSize;
  MacroAssembler masm(buffer_size);

  BenchTimer timer;

  size_t iterations = 0;
  do {
    masm.Reset();
    {
      ExactAssemblyScope scope(&masm, buffer_size);
      Label target;
      for (size_t i = 0; i < buffer_instruction_count; ++i) {
        masm.b(&target);
      }
      masm.bind(&target);
    }
    masm.FinalizeCode();
    iterations++;
  } while (!timer.HasRunFor(cli.GetRunTimeInSeconds()));

  cli.PrintResults(iterations, timer.GetElapsedSeconds());
  return cli.GetExitCode();
}