C standard specifies that array should be declared with a non null size
or with * for standard array. Declaration of relocs_info in tcc.h was
not respecting this rule. This commit add a R_NUM macro that maps to the
R_<ARCH>_NUM macros and declare relocs_info using it. This commit also
moves all linker-related macros from <arch>-gen.c files to <arch>-link.c
ones.
With -run the call instruction and a defined function can be
far away, if the function is defined in the executable itself,
not in the to be compiled code. So we always need PLT slots
for -run, not just for undefined symbols.
This is a work-around for TCC's linker, on AArch64, not building a PLT
when TCC is invoked with "-run". Fixing the linker should be possible:
it works on arm and x86_64, apparently.
* Documentation is now in "docs".
* Source code is now in "src".
* Misc. fixes here and there so that everything still works.
I think I got everything in this commit, but I only tested this
on Linux (Make) and Windows (CMake), so I might've messed
something up on other platforms...
Jsut for testing. It works for me (don't break anything)
Small fixes for x86_64-gen.c in "tccpp: fix issues, add tests"
are dropped in flavor of this patch.
Pip Cet:
Okay, here's a first patch that fixes the problem (but I've found
another bug, yet unfixed, in the process), though it's not
particularly pretty code (I tried hard to keep the changes to the
minimum necessary). If we decide to actually get rid of VT_QLONG and
VT_QFLOAT (please, can we?), there are some further simplifications in
tccgen.c that might offset some of the cost of this patch.
The idea is that an integer is no longer enough to describe how an
argument is stored in registers. There are a number of possibilities
(none, integer register, two integer registers, float register, two
float registers, integer register plus float register, float register
plus integer register), and instead of enumerating them I've
introduced a RegArgs type that stores the offsets for each of our
registers (for the other architectures, it's simply an int specifying
the number of registers). If someone strongly prefers an enum, we
could do that instead, but I believe this is a place where keeping
things general is worth it, because this way it should be doable to
add SSE or AVX support.
There is one line in the patch that looks suspicious:
} else {
addr = (addr + align - 1) & -align;
param_addr = addr;
addr += size;
- sse_param_index += reg_count;
}
break;
However, this actually fixes one half of a bug we have when calling a
function with eight double arguments "interrupted" by a two-double
structure after the seventh double argument:
f(double,double,double,double,double,double,double,struct { double
x,y; },double);
In this case, the last argument should be passed in %xmm7. This patch
fixes the problem in gfunc_prolog, but not the corresponding problem
in gfunc_call, which I'll try tackling next.
The common code to move a returned structure packed into
registers into memory on the caller side didn't take the
register size into account when allocating local storage,
so sometimes that lead to stack overwrites (e.g. in 73_arm64.c),
on x86_64. This fixes it by generally making gfunc_sret also return
the register size.
__clear_cache is defined in lib-arm64.c with a single call to
__arm64_clear_cache, which is the real built-in function and is
turned into inline assembler by gen_clear_cache in arm64-gen.c