ulab code size of certain functions grew a lot with gcc13, when not used with LTO

[dhalbert]

ulab commit: eacb0c9

ARM just released a gcc13 toolchain: https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads.

CircuitPython just converted the main branch of CircuitPython to use gcc 13. In general we see a decrease of code size with gcc13 compared with gcc 2. But for ulab compiled on a build without LTO, we see a substantial increase. See https://github.com/adafruit/circuitpython/pull/8546#issuecomment-1787472714. If you expand > diffs.txt in that comment, an scroll to the end, you'll see that the functions with the largest increase in byte size are:

...
152 numerical_sum_mean_std_ndarray
206 ndarray_binary_add
206 ndarray_binary_multiply
232 ndarray_inplace_ams
570 ndarray_binary_equality
700 compare_function
712 ndarray_get_slice
764 ndarray_binary_power
798 ndarray_binary_subtract
824 ndarray_binary_floor_divide
846 ndarray_binary_true_divide
1606 ndarray_binary_more

This increase does not show up on LTO builds: see the atmel-samd Metro M4 numbers in that comment. But on non-LTO builds, there is a substantial increase. I tested a couple of ports and see increases on stm and raspberrypi (RP2040).

I haven't looked at these functions to see what might be unusual about them yet.

[v923z]

Thanks for the info! I'll try to look into this in the near future.