Function NegateFloatingPointConstant

source/opt/folding_rules.cpp:247–265

Returns the negation of |c|. |c| must be a 32 or 64 bit floating point constant.

// Returns the negation of |c|. |c| must be a 32 or 64 bit floating point
// constant.
uint32_t NegateFloatingPointConstant(analysis::ConstantManager* const_mgr,
                                     const analysis::Constant* c) {
  assert(c);
  assert(c->type()->AsFloat());
  uint32_t width = c->type()->AsFloat()->width();
  assert(width == 32 || width == 64);
  std::vector<uint32_t> words;
  if (width == 64) {
    utils::FloatProxy<double> result(c->GetDouble() * -1.0);
    words = result.GetWords();
  } else {
    utils::FloatProxy<float> result(c->GetFloat() * -1.0f);
    words = result.GetWords();
  }

  const analysis::Constant* negated_const =
      const_mgr->GetConstant(c->type(), std::move(words));
  return const_mgr->GetDefiningInstruction(negated_const)->result_id();
}

// Negates the integer constant |c|. Returns the id of the defining instruction.
uint32_t NegateIntegerConstant(analysis::ConstantManager* const_mgr,