The C nearbyint function has exactly the semantics that Python's round()
requires, whereas C's round() requires extra steps to handle rounding of
numbers half way between integers. So using nearbyint reduces code size
and potentially eliminates any source of errors in the handling of half-way
numbers.
Also, bare-metal implementations of nearbyint can be more efficient than
round, so further code size is saved (and efficiency improved).
nearbyint is provided in the C99 standard so it should be available on all
supported platforms.
The -ansi flag is used for C dialect selection and it is equivalent to -std=c90.
Because it goes right before -std=gnu99 it is ignored as for conflicting flags
GCC always uses the last one.
This helps to test floating point code on Cortex-M hardware.
As part of this patch the link-time-optimisation was disabled because it
wasn't compatible with software FP support. In particular, the linker
could not find the __aeabi_f2d, __aeabi_d2f etc functions even though they
were provided by lib/libm/math.c.
Scenario: module1 depends on some common file from lib/, so specifies it
in its SRC_MOD, and the same situation with module2, then common file
from lib/ eventually ends up listed twice in $(OBJ), which leads to link
errors.
Make is equipped to deal with such situation easily, quoting the manual:
"The value of $^ omits duplicate prerequisites, while $+ retains them and
preserves their order." So, just use $^ consistently in all link targets.
Replaces RUN_TEST=1 definition; now "make test" in qemu-arm directory
will run tests/basics/ and check that they all succeed.
This patch also enables the test on Travis CI.
This is primarily intended to provide testing of Thumb-specific code within
Travis CI as well as if anyone else want to run it locally. As discussed in
purposes. This is currently agains an emulated Cortex-M3 core, however in
the near future it can extended to support M0, M0+ as well M4 (work in
progress exists in sushihangover/qemu).
It's probably true that most of the code base can be covered running uPy
natively on a POSIX system, however we do have the tiny bit of assembly
code. There may exist bugs related to endianness and type aliases, let
alone potential standard library or compiler bugs or even
architecture-specific optimisations.
This could also incorporate lwIP (or other TCP/IP stack) integration as well
as SDIO+FATFS drivers.
The solution to inline the test cases was chose due to simplicity. It could
alternatively be implemented in a number of different way (see #515), but
this looked the simplest.
Inclusion of tinytest was just to avoid writing boilerplate code for
counting failed tests and other utility functions. Currently only a few
functions are used, however this could be extended. Checking in the code
instead of using submodule was a personal preference, but if people do want
the pain of submodules, this can provided. This particular framework is
also pretty good if one desires to run unit test on target. The approach
with scripts being inlined is probably not quite suited for the size of
memory an MCU has, but the tinytest itself should be good, if lower-level C
code is to be unit tested.
