uncovered by the backtrace/boundcheck tests:
* handle STT_SECTION symbols
* call tcc_add_runtime (to get the bcheck.o/bt-exe.o files added)
* add .stab strtab into segments (we should probably add all stab
syms to the output LC_SYMTAB eventually, but right now TCC uses
32 bit stabs, while mach-o uses 32/64bit stabs
* <malloc.h> isn't as portable as <stdlib.h>
* skip 113_btdll.c on Darwin
* replace [...]\+ with [...]\{1,\} in the sed regex (basic REs
have no + even some sed(1) accept it as \+, but bounds _are_ part
of POSIX BREs)
for handling leading underscores when looking up symbols.
Necessary on MacOS, as there C symbols have a '_' prepended.
get_sym_addr (replacing get_elf_sym_addr) gets an argument to
specify if bare/raw/ELF symbols should be looked up or if decorated
C symbols should be looked up. That reflects into tcc_get_symbol.
tcc_add_symbol is _not_ yet changed, but probably should be.
all C/C++/ObjC symbols in symbols tables have a leading underscore
in Mach-O. Within TCC there's some confusion with tcc_add_symbol
(not adding it) and tcc_get_elf_symbol (not expecting it), and
resolve_syms (using dlsym, which doesn't expect it) and -run support.
But this sort of works.
these are resolved non-lazy for now. We only need to generate
the jump stub (using the GOT slot that will be initialized due
to the non-lazy pointer marking, like with data symbols). On
x86-64 we don't even need special marking of these stubs (with
S_SYMBOL_STUBS and associated additional indirect symbol entries),
as that's only used on i386 (where the stubs are self-modifying).
So, this now works:
extern int _printf(const char*, ...);
int _start(void)
{
_printf("hello\n");
return 0;
}
at least data symbols coming from dylibs can be used now, as in the
below. Note in the example that optind is defined in libc (really in
libsystem_c.dylib, reexported from libSystem.B.dylib):
static int loc;
extern int _optind;
int _start(void)
{
_optind = 0;
loc = 42 + _optind;
return loc - 42;
}
if a GOT slot is required (due to codegen, indicated by
presence of some relocation types), then it needs to contain
the address of the wanted symbol, also when it's local and defined,
i.e. not overridable. For simplicity we use a GOT slot for that as
well (other storage would require rewriting relocs and symbols,
as resolving of GOT relocs is hardwired to be based on s1->got).
But that means we need to fill in its indirect symbol mapping slot as
well, for which Mach-O provides a mean to say "not symbol based,
resolved locally". So this fixes this testcase:
static int loc;
int _start(void)
{
loc = 42;
return loc - 42;
}
(where our codegen currently uses a GOT-based access for the write
by accident)
this now sorts the symbols properly (local, global defined, undefined;
the latter two by name), marks the three ranges within LC_DYSYMTAB,
generates a __got section (non-lazy pointers) and slots for
relocations which need them, and the indirect symbol mapping for
them.
This doesn't yet deal with undefined symbols. But it means compared to
last example now this also works, i.e. read access to _global_ data:
% cat simple3.c
int loc = 42;
int _start(void)
{
return loc - 42;
}
this creates a proper LC_SYMTAB, with reasonable entries. It's
not sorted, so not usable for LC_DYSYMTAB. But 'nm -x -no-sort'
allows to see us some useful info.
This also relocates sections and symbols, so now this example
works as well (i.e. read access to static local data):
% cat simple2.c
static int loc = 42;
int main(void)
{
return loc - 42;
}
this does generate a working executable for a very simple
example input, e.g. this:
% cat simple.c
int main(void)
{
return 0;
}
% ./tcc -B. -c simple.c
% ./tcc -nostdlib -B. simple.o -lc
% ./a.out && echo okay
okay
(the -lc is actually not necessary right now, see below). This
has many limitations:
* no symbol table, hence no calls to external functions from
e.g. libc, aka libSystemB
* no proper entry point (should be main, but is hardcoded to first
real .text address)
* libSystemB is hardcoded, no other libs are supported (but again
no external calls anyway)
* generated Mach-O executable is in old format: neither LC_DYLD_INFO
no export tries for symbols are created (no symbol table at all!)
* the __LINKEDIT segment is faked and empty, as dyld doesn't like
it empty even if no symbols point into it
* same with __DATA, dyld wants a non-empty writable segment which
we enforce with useless data
* no relocations, hence no function call stubs (lazy or not) are
generated
* hardcodes some other constants as well
we ignore dylibs for now (can't inspect them yet for meta-info).
Also don't try to load GNU linker scripts, it's simply an unknown file
type (e.g. when mentioning Mach-O object files).
cctools for MacOS 10.14 (at least) unconditionally uses the
__has_include preprocessor directive (i.e. without checking
if defined __has_include
as normally suggested for portable code). So we need to handle
it a little bit. For now we simply say "nope" aka evaluate to 0.
- call TOK_GET() as a function only for tokens with values
- get rid of 'next_nomacro_spc()'
- be sligtly more efficient in next()
This made about 4-5%+ speed in my tests.
Also: tcc.h: reorder tokens
It might have advantages in cases if tcc/libtcc does not
depend on extern files.
Also:
- apply "stray \\ ..." check to macros only. For files it
was already checked. Add positive test.
from e640ed1aeb
Also:
- cleanup -std, -O, -pthread
- tcc.h:win32: use win32-type include paths even for cross
compilers (needed for loading tcc_predefs.h in cases)
- Makefile: simplify OSX .dylib clause
Add code for VT_FUNC.
Use octal number for unsigned int/unsigned long for 32 bits targets.
Add VT_BYTE | VT_UNSIGNED for targets with default unsigned signed char.
Remove extra ',' in default_debug struct.
Checked on:
- i386/x86_64 (linux/windows)
- arm/arm64 (rapberry pi)
- riscv64 (simulator)
Not tested for arm softfloat because raspberry pi does not support it.
Modifications:
Makefile:
add arm-asm.c to arm64_FILES
add riscv64-asm.c (new file) to riscv64_FILES
lib/Makefile:
add fetch_and_add_arm.o(new file) to ARM_O
add fetch_and_add_arm64.o(new file) to ARM64_O
add fetch_and_add_riscv64.o(new file) to RISCV64_O
add $(BCHECK_O) to OBJ-arm/OBJ-arm64/OBJ-riscv64
tcc.h:
Enable CONFIG_TCC_BCHECK for arm32/arm64/riscv64
Add arm-asm.c, riscv64-asm.c
tcctok.h:
for arm use memmove4 instead of memcpy4
for arm use memmove8 instead of memcpy8
tccgen.c:
put_extern_sym2: for arm check memcpy/memmove/memset/memmove4/memmove8
only use alloca for i386/x86_64
for arm use memmove4 instead of memcpy4
for arm use memmove8 instead of memcpy8
fix builtin_frame_address/builtin_return_address for arm/riscv64
tccrun.c:
Add riscv64 support
fix rt_getcontext/rt_get_caller_pc for arm
tccelf.c:
tcc_load_dll: Print filename for bad architecture
libtcc.c:
add arm-asm.c/riscv64-asm.c
tcc-doc.texi:
Add arm, arm64, riscv64 support for bound checking
lib/bcheck.c:
add __bound___aeabi_memcpy/__bound___aeabi_memmove
__bound___aeabi_memmove4/__bound___aeabi_memmove8
__bound___aeabi_memset for arm
call fetch_and_add_arm/fetch_and_add_arm64/fetch_and_add_riscv64
__bound_init: Fix type for start/end/ad
__bound_malloc/__bound_memalign/__bound_realloc/__bound_calloc: Use size + 1
arm-gen.c:
add bound checking code like i386/x86_64
assign_regs: only malloc if nb_args != 0
gen_opi/gen_opf: Fix reload problems
arm-link.c:
relocate_plt: Fix address calculating
arm64-gen.c:
add bound checking code like i386/x86_64
load/store: remove VT_BOUNDED from sv->r
arm64_hfa_aux/arm64_hfa_aux: Fix array code
gfunc_prolog: only malloc if n != 0
arm64-link.c:
code_reloc/gotplt_entry_type/relocate: add R_AARCH64_LDST64_ABS_LO12_NC
relocate: Use addXXle instead of writeXXle
riscv64-gen.c:
add bound checking code like i386/x86_64
add NB_ASM_REGS/CONFIG_TCC_ASM
riscv64-link.c:
relocate: Use addXXle instead of writeXXle
i386-gen.c/x86_64-gen.c
gen_bounds_epilog: Fix code (unrelated)
tests/Makefile:
add $(BTESTS) for arm/arm64/riscv64
tests/tests2/Makefile:
Use 85 only on i386/x86_64 because of asm code
Use 113 only on i386/x86_64 because of DLL code
Add 112/114/115/116 for arm/arm64/riscv64
Fix FILTER (failed on riscv64)
tests/boundtest.c:
Only use alloca for i386/x86_64
an enum must be compatible with one or more integer type,
so adjust the test accordingly. That means the following
redeclarations should work:
enum e6 { E1 = -1, E0 };
void f3(enum e6);
void f3(int); // should work as int and e6 are compatible
while the following should not:
void f4(enum e6 e);
void f4(unsigned e); // should error as unsigned and e6 are incompatible
they were emitted too early, in particular also in macro
substitution which might turn out to not be stray in case it's
further stringified. Check in next() instead. Add two testcases
that an error is still emitted for obvious top-level baskslashes,
and that stringifying such a thing works.
i386-gen.c:
- load/gen_opf: set v1.sym to NULL
lib/Makefile:
- Add -gstabs -fno-omit-frame-pointer -Wno-unused-function -Wno-unused-variable
lib/bt-log.c:
- tcc_backtrace: Prevent __builtin_frame_address warning
tccgen.c:
- struct_layout: Set t.t to VT_BYTE
- default_debug: Use octal instead of -1 to make size_t work
tccpp.c:
- tal_realloc_impl: Only memcpy when p set
x86_64-gen.c:
- gen_bounds_epilog: Do not save/restore rcx (not caller/callee saved)
This also made stack not aligned to 16 bytes.
tcctok.h:
- Add __bound_setjmp/setjmp/_setjmp/longjmp
tccgen.c:
- redirect setjmp/longjmp to bcheck.c code
i386-gen.c/x86_64-gen.c
- Change func_bound_alloca_used into func_bound_add_epilog
- Set func_bound_add_epilog also when setjmp is called
bcheck.c:
- Add __bound_setjmp/__bound_longjmp
- __bound_local_delete: remove setjmp if used in function
- __bound_exit: clear setjmp list and print statistic
- make malloc_redir more readable (unrelated)
New testcases:
- 115_bound_setjmp
- 116_bound_setjmp2
Merge function attributes with those given given for the
prototype, also handle post-decl appearance such as
void func() __attribute__((noreturn))
{
}
Also, some test fixes (unrelated).
from 3e731e3a78
tccgen.c:
- make 'struct default_debug' const
- pass TCCState* as parameter to tcc_debug_xxx functions
- always check tcc_state->do_debug before calling functions
- factor out tcc_debug_extern_sym()
- remove formats "%lld"/"%llu" (not reliable on windows)
xxx-gen files:
- set func_vt/var from caller
for simplicity handles like -v (verbose), but enables the usual idiom
of configure scripts to use '$CC --version' to find out the compiler
variant and version.
This allows debugging with variables/structs/unions/enums/bitfields.
Add new functions:
- tcc_debug_stabs: store stabs debug info
- tcc_debug_stabn: store stabn debug info
- tcc_get_debug_info: generate stabs debug info
- tcc_debug_finish: store debug info in debug section
- tcc_add_debug_info: Add function debug info
Update functions:
- tcc_debug_end: free debug hash
- tcc_debug_funcstart: Generate correct function debug info
- tcc_debug_funcend: Finish debug info
- put_extern_sym2: Generate debug info for symbols
- pop_local_syms: Add debug info
- prev_scope: Add local symbols
it doesn't round so the RM field can be zero. According to some
sourcs it should be set to zero by software in these cases, and
the binutils disassembler doesn't like us setting it to 7.
This shouldn't matter in practice, but who knows.
