diff options
| -rw-r--r-- | src/numeric.c | 19 | ||||
| -rw-r--r-- | test/t/integer.rb | 3 |
2 files changed, 19 insertions, 3 deletions
diff --git a/src/numeric.c b/src/numeric.c index e64cd2d8d..41820ff5c 100644 --- a/src/numeric.c +++ b/src/numeric.c @@ -821,15 +821,28 @@ static mrb_value lshift(mrb_state *mrb, mrb_int val, mrb_int width) { mrb_assert(width > 0); - if ((width > NUMERIC_SHIFT_WIDTH_MAX) || - (val > (MRB_INT_MAX >> width))) { + if (val > 0) { + if ((width > NUMERIC_SHIFT_WIDTH_MAX) || + (val > (MRB_INT_MAX >> width))) { + goto bit_overflow; + } + } else { + if ((width > NUMERIC_SHIFT_WIDTH_MAX) || + (val < (MRB_INT_MIN >> width))) { + goto bit_overflow; + } + } + + return mrb_fixnum_value(val << width); + +bit_overflow: + { mrb_float f = (mrb_float)val; while (width--) { f *= 2; } return mrb_float_value(mrb, f); } - return mrb_fixnum_value(val << width); } static mrb_value diff --git a/test/t/integer.rb b/test/t/integer.rb index c6084bfeb..5379744e5 100644 --- a/test/t/integer.rb +++ b/test/t/integer.rb @@ -150,6 +150,9 @@ assert('Integer#<<', '15.2.8.3.12') do # Left Shift by 31 is bitShift overflow to SignedInt assert_equal 2147483648, 1 << 31 + + # -3 Left Shift by 30 is bitShift overflow to SignedInt + assert_equal -3221225472, -3 << 30 end assert('Integer#>>', '15.2.8.3.13') do |