The goal was to improve readability, but along the way a few things were
gained.
- Sorted sym and map files
- Infrastructure for supporting multiple .o versions
- Valgrind-proof, as far as my testing goes anyways
- Improved verbosity messages
- Added error checking
- Performance improvements, see end of commit message
The readability improvement was spurred while trying to make sense of the
old code while trying to implement features such as sorted sym and map
files.
I also did my best to remove hardcoded logic, such that modifications
should be doable; for example, "RAM loading" sections, which are linked
against a different location than the one they're stored at.
Some work remains to be done, see the "TODO:" and "FIXME:" comments.
Further, while regression tests pass, this new linker should be tested on
different codebases (ideally while instrumented with `make develop` and
under valgrind).
The few errors spotted in the man pages (alignment) need to be corrected.
Finally, documentation comments need to be written, I have written a lot of
them but not all.
This also provides a significant performance boost (benchmarked with a
51994-symbol project):
Current master RGBLINK:
2.02user 0.03system 0:02.06elapsed 99%CPU (0avgtext+0avgdata 84336maxresident)k
0inputs+11584outputs (0major+20729minor)pagefaults 0swaps
Rewritten RGBLINK:
0.19user 0.06system 0:00.63elapsed 40%CPU (0avgtext+0avgdata 32460maxresident)k
23784inputs+11576outputs (0major+7672minor)pagefaults 0swaps
They do not take any room, so they can only be used to define symbols at
a given location. I ran into trouble with such a SECTION failing to be
placed where specified, which doesn't make sense.
This way, it also makes sense to have such a SECTION in the middle of
another one, but that should be fine, since there's no actual overlap.
The linker script now allows you to assign a section with the same
attributes as in the source.
To do this, I've removed a check from AssignSectionAddressAndBankByName
that would never be triggered, due to that condition being checked
before. Shouldn't this and IsSectionSameTypeBankAndAttrs be condensed
into a single function?
Two variables, pSection->Data and tSymbols, were previously set to ‘dummymem’, a global variable that was otherwise not used.
As this can potentially cause alignment warnings on Clang, this commit replaces that mechanism with a plain old NULL pointer, which is more generally used as a dummy pointer value.
Signed-off-by: Ben10do <Ben10do@users.noreply.github.com>
GCC has an Undefined Behavior Sanitizer (ubsan), which enables run-time
checks of undefined behaviour. It has been enabled for the `develop`
build target.
A small bug detected with it has been fixed.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Previously, the output file was opened before trying to open the
overlay. Because of this, rgblink generated an empty output file if the
overlay couldn't be opened.
Now the overlay is opened (and checked) before the output file, so the
output file is only generated if the overlay is found.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Added define 'unused_' for '__attribute__((unused))'. The oldest version
of GCC with online docs (GCC 2.95.3, released in March 16, 2001 [1])
already has support for this attribute, so it doesn't make sense to
check the version.
Renamed 'noreturn' to 'noreturn_' for consistency.
[1] https://gcc.gnu.org/onlinedocs/
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Previously, JR was only allowed to labels (in the same section, or
different sections). When trying to JR to an address specified as a
numeric value, rgbasm would fail to calculate the JR offset (as it
doesn't know the final address of the JR so it can't calculate the
difference).
This patch makes rgblink calculate the offset whenever there is a JR.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Previously, JR was only allowed if the destination label was in the same
section as the JR. This patch removes this restriction. The check to see
if the relative value overflows is now done when linking the ROM.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
With permission from the main authors [1], most of the code has been
relicensed under the MIT license.
SPDX license identifiers are used so that the license headers in source
code files aren't too large.
Add CONTRIBUTORS.rst file.
[1] https://github.com/rednex/rgbds/issues/128
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
NULL error messages have been given a description.
Messages that weren't descriptive enough now also print the name of the
function that has failed.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
ROMX and WRAMX bank numers are stored in an object file as their number
minus one. This means that this offset has to be applied somewhere.
The old code applied the fix for ROMX and WRAMX in two different places.
It looks like the patch that added support for WRAMX didn't set the
offset correctly in 'src/link/assign.c'. When this was fixed, it was
done in the wrong place, in 'src/asm/asm.y'. This patch moves the fix to
'src/link/assign.c'.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
