factor/vm/safepoints.cpp

#include "master.hpp"

namespace factor {

void factor_vm::enqueue_fep() {
  if (fep_p)
    fatal_error("Low-level debugger interrupted", 0);
  atomic::store(&safepoint_fep_p, true);
  code->set_safepoint_guard(true);
}

void factor_vm::enqueue_samples(cell samples,
                                cell pc,
                                bool foreign_thread_p) {

  if (!atomic::load(&sampling_profiler_p))
    return;
  atomic::fetch_add(&current_sample.sample_count, samples);

  if (foreign_thread_p)
    atomic::fetch_add(&current_sample.foreign_thread_sample_count, samples);
  else {
    if (atomic::load(&current_gc_p))
      atomic::fetch_add(&current_sample.gc_sample_count, samples);
    if (atomic::load(&current_jit_count) > 0)
      atomic::fetch_add(&current_sample.jit_sample_count, samples);
    if (!code->seg->in_segment_p(pc))
      atomic::fetch_add(&current_sample.foreign_sample_count, samples);
  }
  code->set_safepoint_guard(true);
}

// Allocates memory (record_sample)
void factor_vm::handle_safepoint(cell pc) {
  code->set_safepoint_guard(false);
  faulting_p = false;

  if (atomic::load(&safepoint_fep_p)) {
    if (atomic::load(&sampling_profiler_p))
      end_sampling_profiler();
    std::cout << "Interrupted\n";
    if (stop_on_ctrl_break) {
      /* Ctrl-Break throws an exception, interrupting the main thread, same
         as the "t" command in the factorbug debugger. But for Ctrl-Break to
         work we don't require the debugger to be activated, or even enabled. */
      atomic::store(&safepoint_fep_p, false);
      general_error(ERROR_INTERRUPT, false_object, false_object);
      FACTOR_ASSERT(false);
    }
    factorbug();
    atomic::store(&safepoint_fep_p, false);
  } else if (atomic::load(&sampling_profiler_p)) {
    FACTOR_ASSERT(code->seg->in_segment_p(pc));
    code_block* block = code->code_block_for_address(pc);
    bool prolog_p = block->entry_point() == pc;

    record_sample(prolog_p);
  }
}

}