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
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?
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>
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>
The bank of a section can be requested with `BANK("Section Name")`, and
the bank of the current section with `BANK(@)`. In both cases, the bank
number is resolved by the linker.
New commands have been added to the list of RPN commands of object
files, and the rest has been moved so that new additions don't force a
new change in the number of the enumerations.
Increase object file version, as it is now incompatible with the old
format.
Update manpages to reflect the new ways of using `BANK()` and the new
format of the object files.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Not all occurrences have been replaced, in some cases they have been
left as they were before (like in rgbgfx and when they are in the
interface of a C standard library function).
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
This is useful to generate error messages when there is a symbol that
appears in more than one object file.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
rgblink option -w has been restored to its previous behaviour: make WRAM
a continous section instead of spliting it into WRAM0 and WRAMX.
To enable DMG mode, option -d has to be used instead. This option
automatically enables -w.
Update tests.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
If the next release is going to break compatibility with older object
file formats it doesn't make sense to keep this.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Files can now be included with the following syntax:
INCLUDE "path.link"
The maximum include depth is 5.
Fixed linkerscript parser and lexer error messages so that they are more
informative (show file and line of the error).
Man page updated.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
This patch isn't used because it's meant to be an optimization for
labels in the memory region 0x2000-0x20FF. That memory region doesn't
have anything special on the Game Boy, and there are no instructions
optimized to read or write from there, so it was probably meant for
another hardware that was supported by ASMotor in the past.
Signed-off-by: AntonioND <antonio_nd@outlook.com>
Even though the bank number was read from the linkerscript and the
linker verified that each section could be mapped in the final rom, the
bank number was never actually set by the linkerscript parser.
Signed-off-by: AntonioND <antonio_nd@outlook.com>
To make the behaviour of the linkerscript consistent, every section read
from an object file must have an unique name. This is needed as the
linkerscript uses the name of sections to place them and it expects
every section to have a different name.
This doesn't break compatibility with the old behaviour that allowed to
continue sections if they had the same name, bank number and starting
address. That's still allowed because `rgbasm` outputs a single section
if this functionality is used, it is transparent to `rgblink`.
Signed-off-by: AntonioND <antonio_nd@outlook.com>
Previously, some instances of the number of banks for each section remained hardcoded. These have been replaced with BANK_COUNT_* constants.
As a side-effect, this could fix a theoretical bug when using BANK(label) when the label is in a high SRAM bank (≥ 4).
Aligned sections can now be created with out_NewAlignedSection(). This information is stored in created object files, and read by the linker.
The names of each section are also included in the object file, enabling potential improvements to error messages in the future.
