sub_from() [2/2]

int32_t safe::sub_from ( int32_t & x, int32_t y, const char * msg )

inlinestatic

Definition at line 158 of file overflow.hpp.

{
  int32_t z = (uint32_t)x - (uint32_t)y;
  if
    expect_false((int32_t)((uint32_t)x ^ (uint32_t)z) < 0 &&
                 (int32_t)((uint32_t)x ^ (uint32_t)y) < 0) ov(msg);
  return x = z;
}

References expect_false, ov(), and x.

Referenced by sub_from().