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diff --git a/gas/README.rich b/gas/README.rich deleted file mode 100644 index 1ac53c7..0000000 --- a/gas/README.rich +++ /dev/null @@ -1,143 +0,0 @@ - - - The Code Pedigree of This Directory - - -This directory contains a big merge of several development lines of -gas as well as a few bug fixes and some configuration that I've added -in order to retain my own sanity. - -A little history. - -The only common baseline of all versions was gas-1.31. - -From 1.31, Intel branched off and added: - - support for the Intel 80960 (i960) processor. - support for b.out object files. - some bug fixes. - sloppy mac MPW support - Intel gnu/960 makefiles and version numbering. - -Many of the bug fixes found their way into the main development line -prior to 1.36. ALL intel changes were ifdef'd I80960. This was good -as it isolated the changes, but bad in that it connected the b.out -support to the i960 support, and bad in that the bug fixes were only -active in the i960+b.out executables of gas, (although most of these -were nicely marked with comments indicating that they were probably -general bug fixes.) - -To pick up the main FSF development line again, along the way to 1.36, -several new processors were added, many bugs fixed, and the world was -a somewhat better place in general. - -From gas-1.36, Loic at Axis Design (france!) encapsulated object -format specific actions, added coff versions of those encapsulations, -and a config.gas style configuration and Makefile. This was a big -change and a lot of work. - -Then along came the FIRST FSF release of gas-1.37. I say this because -there have been at least two releases of gas-1.37. Only two of them -do we care about for this story, so let's call them gas-1.37.1 and -gas-1.37.2. - -Here starts the confusion. Firstly, gas-1.37.1 did not compile. - -In the meantime, John Gilmore at Cygnus Support had been hacking -gas-1.37.1. He got it to compile. He added support for the AMD 29000 -processor. AND he started encapsulating some of the a.out specific -pieces of code mostly into functions. AND he rebuilt the relocation -info to be generic. AND he restructured somewhat so that for a single -host, cross assemblers could be built for all targets in the same -directory. Useful work but a considerable nuisance because the a29k -changes were not partitioned from the encapsulation changes, the -encapsulation changes were incomplete, and the encapsulation required -functions where alternate structuring might have used macros. Let's -call this version gas-1.37.1+a29k. - -By the time gas-1.37.2 was "released", (remember that it TOO was -labelled by FSF as gas-1.37), it compiled, but it also added i860 -support and ansi style const declarations. - -At this point, Loic rolled his changes into gas-1.37.2. - -What I've done. - -I collected all the stray versions of gas that sounded relevant to my -goals of cross assembly and alternate object file formats and the FSF -releases from which the stray versions had branched. - -I rolled the Intel i960 changes from 1.31 into versions that I call -1.34+i960, 1.36+i960, and then 1.37.1+i960. - -Then I merged 1.37.1+i960 with 1.37.1+a29k to produce what I call -1.37.1+i960+a29k or 1.37.3. - -From 1.37.3, I pulled in Loic's stuff. This wasn't easy as Loic's -stuff hit all the same points as John's encapsulations. Loic's goal -was to split the a.out from coff dependancies for native assembly on -coff, while John's was to split for multiple cross assembly from a -single host. - -Loic's config arranged files much like emacs into m-*, etc. I've -rearranged these somewhat. - -Theory: - -The goal of the new configuration scheme is to bury all object format, -target processor, and host machine dependancies in object, target, and -host specific files. That is, to move all #ifdef's out of the gas -common code. - -Here's how it works. There is a .h and a .c file for each object file -format, a .h and a .c file for each target processor, and a .h for -each host. config.gas creates {sym}links in the current directory to -the appropriate files in the config directory. config.gas also serves -as a list of triplets {host, target, object-format} that have been -tested at one time or another. I also recommend that config.gas be -used to document triplet specific notes as to purpose of the triplet, -etc. - -Implementation: - -host.h is a {sym}link to .../config/xm-yourhost.h. It is intended to -be used to hide host compiler, system header file, and system library -differences between host machines. If your host needs actual c source -files, then either: these are generally useful functions, in which -case you should probably build a local library outside of the gas -source tree, or someone, perhaps me, is confused about what is needed -by different hosts. - -obj-format.h is a {sym}link to .../config/obj-something.h. It is intended - -All gas .c files include as.h. - -as.h #define's "gas", includes host.h, defines a number of gas -specific structures and types, and then includes tp.h, obj.h, and -target-environment.h. - -target-environment.h defines a target environment specific -preprocessor flag, eg, TE_SUN, and then includes obj-format.h. - -obj-format.h defines an object format specific preprocessor flag, eg, -OBJ_AOUT, OBJ_BOUT, OBJ_COFF, includes "target-processor.h", and then -defines the object specific macros, functions, types, and structures. - -target-processor.h - -target-processor. - -Porting: - -There appear to be four major types of ports; new hosts, new target -processors, new object file formats, and new target environments. - - ------ - -reloc now stored internally as generic. (symbols too?) (segment types -vs. names?) - -I don't mean to overlook anyone here. There have also been several -other development lines here that I looked at and elected to bypass. -Specifically, xxx's stabs in coff stuff was particularly tempting. |