Hi Jacob, interesting project. On my linux machine I also needed to link -lz.
ys, Jona > On 1. Jul 2023, at 14:07, jacob navia <ja...@jacob.remcomp.fr> wrote: > > Hi > > I have developed a new version of the gnu assembler for riscv machines. > > Abstract: > ——— > > The GNU assembler (gas) is centered on flexibility and portability. These two > objectives have quite a cost in program readability, code size and execution > time. > > I have developed a « tiny » version of the GNU assembler focusing on > simplicity and speed. > > I have picked up from the several hundreds of megabytes of binutils just the > routines that are needed to a functional assembler, for the use case of > compiler generated assembler text for a single machine. That meant: > > 1) There is no linker code in this assembler. An assembler doesn’t need any > linker code. It is an assembler, period. > 2) There are no macros, no preprocessing, nothing that makes an assembler > easier to use for a human developer. This is NOT a replacement of gas, that > is obviously still available everywhere. If you want to develop in assembler > use gas, not this tiny assembler. > 3) Since there isn’t a human user, all the sophisticated error handling is > not necessary. Messages are in English ONLY and if you do not know that > language just do not make any mistakes! > 4) All the vectorization for separating the front end and the backend are > eliminated. There is no indirection through function tables the functions in > the backend are called directly. This has the advantage that when you see a > function call like statement like foo(42); it means that you are calling the > « foo » function, not a macro that is expanded into something else then > renamed to yet another name. > 5) The BFD library has been disabled. Only some procedures of that library > are in the code. The same for libierty, that has almost vanished. > 6) The code has been cleaned up from all cruft like this: > /* The magic number BSD_FILL_SIZE_CROCK_4 is from BSD 4.2 VAX > * flavoured AS. The following bizarre behaviour is to be > * compatible with above. I guess they tried to take up to 8 > * bytes from a 4-byte expression and they forgot to sign > * extend. */ > #define BSD_FILL_SIZE_CROCK_4 (4) > > So, we are still in 2023 keeping bug compatibility with an assembler for a > machine that ceased production in 2000? > > In a similar vein, all code that referenced the Motorola 68000 (an even older > machine) the Z80, the SUN SPARC, etc is gone. This assembler will only > produce 64 bits ELF code and compile for a 64 bit risk CPU. > > Availability: > $ git clone https://github.com/jacob-navia/tiny-asm > > Building the tiny assembler: > $ gcc -o asm asm.c > > There is no Makefile > > In some machines, the obstack library is not a part of the libc. (Not linux, > Apple, for instance). For those machines obtsack.c is provided in the > distribution and the compilation command should be: > $ gcc -o asm asm.c obstack.c > > star64:~/riscv-asm$ objdump -h asm | grep text > 11 .text 0002e53e 0000000000028060 0000000000028060 00028060 2**2 > > Just 189 758 bytes. The gnu assembler is: > star64:~/riscv-asm$ objdump -h ../binutils-gdb/gas/as-new | grep text > 11 .text 000d8d10 00000000000465a0 00000000000465a0 000465a0 2**2 > 888 080 bytes. > > Further work: > The idea is to replace the system assembler in gcc and replaced with a linked > assembler that speeds gcc: instead of writing an assembler file you just pass > a pointer to the text buffer in memory. > But that is still much further down the road. > > Enjoy! > > jacob > > >
