The back end functions gen_op(comparison) and gtst() might allocate
registers so case_reg should be left on the value stack while they
are called and set again afterwards.
This for example suppresses string constants such as with
int main()
{
return sizeof "foo";
}
Actually, setting
nocode_wanted = 1;
in libtcc.c for the initial global level seemed wrong, since
obviously "nocode_wanted" means code as any side effects, also
such as string constants.
This reverts a part of 2de1b2d14c
(documented as "Some in-between fixes" in Changelog)
This adds parsing of (GCC compatible) visibility attribute
in order to mark selected global symbols as hidden. The generated
.o files contain hidden symbols already, the TCC linker doesn't
yet do the right thing.
*** UNCONDITIONALLY ***
Esp. sihce tinycc winapi headers are not as complete as people might
expect this can otherwise lead to obscure problems that are difficult
to debug.
(Originally 'warn_implicit_function_declaration' was set to 1
always for windows but someone must have deleted that line)
This was going wrong (case TOK_LAND in unary: computed labels)
- vset(&s->type, VT_CONST | VT_SYM, 0);
- vtop->sym = s;
This does the right thing and is shorter:
+ vpushsym(&s->type, s);
Test case was:
int main(int argc, char **argv)
{
int x;
static void *label_return = &&lbl_return;
printf("label_return = %p\n", label_return);
goto *label_return; //<<<<< here segfault on linux X86_64 without the memset on vset
printf("unreachable\n");
lbl_return:
return 0;
}
Also::
- Rename "void* CValue.ptr" to more usable "addr_t ptr_offset"
and start to use it in obvious cases.
- use __attribute__ ((noreturn)) only with gnu compiler
- Revert CValue memsets ("After several days searching ...")
commit 4bc83ac393
Doesn't mean that the vsetX/vpush thingy isn't brittle and
there still might be bugs as to differences in how the CValue
union was set and is then interpreted later on.
However the big memset hammer was just too slow (-3% overall).
For program manipulating argv or arge as pointer with construct such as:
(while *argv++) {
do_something_with_argv;
}
it is necessary to have argv and arge inside a region. This patch create
regions argv and arge) if main is declared with those parameters.
I found the problem it was because CValue stack variables have rubish as it inital values
and assigning to a member that is smaller than the big union item and trying to
recover it later as a different member gives bak garbage.
ST_FUNC void vset(TCCState* tcc_state, CType *type, int r, int v)
{
CValue cval;
memset(&cval, 0, sizeof(CValue));
cval.i = v; //,<<<<<<<<<<< here is the main bug that mix with garbage
vsetc(tcc_state, type, r, &cval);
}
/* store a value or an expression directly in global data or in local array */
static void init_putv(TCCState* tcc_state, CType *type, Section *sec, unsigned long c,
int v, int expr_type)
{
...
case VT_PTR:
if (tcc_state->tccgen_vtop->r & VT_SYM) {
greloc(tcc_state, sec, tcc_state->tccgen_vtop->sym, c, R_DATA_PTR);
}
//<<< on the next line is where we try to get the assigned value to cvalue.i as cvalue.ull
*(addr_t *)ptr |= (tcc_state->tccgen_vtop->c.ull & bit_mask) << bit_pos;
break;
Also this patch makes vla tests pass on linux 32 bits
When checking for exact compatibility between types (such as in
__builtin_types_compatible_p) consider the case of default signedness to
be incompatible with both of the explicit signedness for char. That is,
char is incompatible with signed char *and* unsigned char, no matter
what the default signedness for char is.
negate(x) is subtract(-0,x), not subtract(+0,x), which makes
a difference with signed zeros. Also +x was expressed as x+0,
in order for the integer promotions to happen, but also mangles signed
zeros, so just don't do that with floating types.
Applying 64bit relocs assumes that the CVal is initialized to zero
for the whole 64bit. Consolidate this a bit, at the same time
zeroing the .ull member more consistently when needed. Fixes segfault
on x86_64-linux using global vars in tcctest.c.
Refactoring (no logical changes):
- use memcpy in tccgen.c:ieee_finite(double d)
- use union to store attribute flags in Sym
Makefile: "CFLAGS+=-fno-strict-aliasing" basically not necessary
anymore but I left it for now because gcc sometimes behaves
unexpectedly without.
Also:
- configure: back to mode 100755
- tcc.h: remove unused variables tdata/tbss_section
- x86_64-gen.c: adjust gfunc_sret for prototype
- tccgen: error out for cast to void, as in
void foo(void) { return 1; }
This avoids an assertion failure in x86_64-gen.c, also.
also fix tests2/03_struct.c accordingly
- Error: "memory full" - be more specific
- Makefiles: remove circular dependencies, lookup tcctest.c from VPATH
- tcc.h: cleanup lib, include, crt and libgcc search paths"
avoid duplication or trailing slashes with no CONFIG_MULTIARCHDIR
(as from 9382d6f1a0)
- tcc.h: remove ";{B}" from PE search path
in ce5e12c2f9 James Lyon wrote:
"... I'm not sure this is the right way to fix this problem."
And the answer is: No, please. (copying libtcc1.a for tests instead)
- win32/build_tcc.bat: do not move away a versioned file
The procedure calling standard for ARM architecture mandate the use of
the base standard for variadic function. Therefore, hgen float aggregate
must be returned via stack when greater than 4 bytes and via core
registers else in case of variadic function.
This patch improve gfunc_sret() to take into account whether the
function is variadic or not and make use of gfunc_sret() return value to
determine whether to pass a structure via stack in gfunc_prolog(). It
also take advantage of knowing if a function is variadic or not move
float result value from VFP register to core register in gfunc_epilog().
Move the logic to do a test of an integer value (ex if (0)) out of
arch-specific code to tccgen.c to avoid code duplication. This also
fixes test of long long value which was only testing the bottom half of
such values on 32 bits architectures.
- avoid assumption "ret_align == register_size" which is
false for non-arm targets
- rename symbol "sret" to more descriptive "ret_nregs"
This fixes commit dcec8673f2
Also:
- remove multiple definitions in win32/include/math.h
On ARM with hardfloat calling convention, structure containing 4 fields
or less of the same float type are returned via float registers. This
means that a structure can be returned in up to 4 double registers in a
structure is composed of 4 doubles. This commit adds support for return
of structures in several registers.
TLS support in tinyCC is absolutely not ready:
- segment register not select in load and store
- no relocation added for computing offset of per-thread symbol
- no support for TLS-specific relocations
- no program header added as per Drepper document about TLS
This reverts commit 1c4afd1350.
Prevent the following code from compiling:
enum color {RED, GREEN, BLUE};
enum color {R, G, B};
int main()
{
return R;
}
Reported-by: John Haque <j.eh@mchsi.com>
Use one more bit in AttributeDef to differenciate between declared
function (only its prototype is known) and defined function (its body is
also known). This allows to generate an error in cases like:
int f(){return 0;}
int f(){return 1;}
VLA storage is now freed when it goes out of scope. This makes it
possible to use a VLA inside a loop without consuming an unlimited
amount of memory.
Combining VLAs with alloca() should work as in GCC - when a VLA is
freed, memory allocated by alloca() after the VLA was created is also
freed. There are some exceptions to this rule when using goto: if a VLA
is in scope at the goto, jumping to a label will reset the stack pointer
to where it was immediately after the last VLA was created prior to the
label, or to what it was before the first VLA was created if the label
is outside the scope of any VLA. This means that in some cases combining
alloca() and VLAs will free alloca() memory where GCC would not.
Also made XMM0-7 available for use as temporary registers, since they
are not used by the ABI. I'd like to do the same with RSI and RDI but
that's trickier since they can be used by gv() as temporary registers
and there isn't a way to disable that.
All tests pass. I think I've caught all the cases assuming only XMM0 is
used. I expect that Win64 is horribly broken by this point though,
because I haven't altered it to cope with XMM1.
I've had to introduce the XMM1 register to get the calling convention
to work properly, unfortunately this has broken a fair bit of code
which assumes that only XMM0 is used.
There are probably still issues on x86-64 I've missed.
I've added a few new tests to abitest, which fail (2x long long and 2x double
in a struct should be passed in registers).
Edmund Grimley Evans