Re: [Tinycc-devel] status of x86-64

[shinichiro . h]

Hi,

> Two questions to you:
> - The TOK_builtin_malloc/free handlers in tcc.c looked a bit messy.
>    I'd like to suggest something different:
>        http://repo.or.cz/w/tinycc.git?a=commitdiff;h=76fe1ed5
>    Does this what you need?

Yes, definitely. Actually, I considered this way, but I somehow
hesitated to add tokens.

> - Also, I had a version of tcc_relocate() that crams everything into one
>    buffer allocated by the caller, such that it can be run independent
>    from a TCCState:
>        http://repo.or.cz/w/tinycc.git?a=commitdiff;h=495dc312
>    Would this would work on x64 instead of your version?

I like this idea. But unfortunately, this needs some fixes for
x86-64. On x86-64, relocation may fail when the distance between
caller and callee is larger than 32bit. In such case, x86-64 TCC
generates PLT and GOT during relocation and it requires extra memory.
Anyway, I'll fix this.

I have two comments on this change.

1. I'm not sure, but you may be able to swap

    /* relocate symbols */
    relocate_syms(s1, 1);
    if (s1->nb_errors)
        return -1;

and

    if (0 == mem)
        return offset + 15;

so that we don't run relocate_syms() twice?

2. How about adding comment which mentions tcc_relocate accepts
   (void *)1 as ptr? If you agree and write some comments, please
   mention that this won't work on x86-64.

> Also two questions to everyone:
> - I changed some prototypes for libtcc, for tcc_relocate() and two other
>        http://repo.or.cz/w/tinycc.git?a=commitdiff;h=4a3907a18
>    I know, people might need to update if they use libtcc in their code.
>    Does anyone think this is a bad idea (or that the changes are per se)?

As I already wrote, I like the new interface of tcc_relocate(). I
guess changing the usage would be acceptable, but I'm not sure.

> - Also, should we make some subdirs now? I was thinking of
>    * include (tcc stdxxx.h)
>    * lib (libtcc1.c, bcheck.c, allocaX.S)
>    * tests (tcctest etc.)
>    It could look cleaner in the distro but less clean in the makefile(s)
>    What do you think?

I think this change would be great. Especially adding tests directory
is nice. I wanted to add some tests which exercise combination of TCC
and GCC (e.g., compile by GCC, and link by TCC), but I didn't add
since I didn't want to increase number of files in the tinycc
directory.

Thanks,