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Add support for Mach-O thread local variables #68

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36 changes: 22 additions & 14 deletions output/outmacho.c
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Original file line number Diff line number Diff line change
Expand Up @@ -575,7 +575,7 @@ static void macho_output(int32_t secto, const void *data,
dfmt->debug_output(0, &sinfo);
}

is_bss = (s->flags & SECTION_TYPE) == S_ZEROFILL;
is_bss = (s->flags & SECTION_TYPE) == S_ZEROFILL || (s->flags & SECTION_TYPE) == S_THREAD_LOCAL_ZEROFILL;

if (is_bss && type != OUT_RESERVE) {
nasm_warn(WARN_OTHER, "attempt to initialize memory in "
Expand Down Expand Up @@ -740,14 +740,19 @@ static const struct macho_known_section {
const char *sectname;
const uint32_t flags;
} known_sections[] = {
{ ".text", "__TEXT", "__text", S_CODE },
{ ".data", "__DATA", "__data", S_REGULAR },
{ ".rodata", "__DATA", "__const", S_REGULAR },
{ ".bss", "__DATA", "__bss", S_ZEROFILL },
{ ".debug_abbrev", "__DWARF", "__debug_abbrev", S_ATTR_DEBUG },
{ ".debug_info", "__DWARF", "__debug_info", S_ATTR_DEBUG },
{ ".debug_line", "__DWARF", "__debug_line", S_ATTR_DEBUG },
{ ".debug_str", "__DWARF", "__debug_str", S_ATTR_DEBUG },
{ ".text", "__TEXT", "__text", S_CODE },
{ ".data", "__DATA", "__data", S_REGULAR },
{ ".rodata", "__DATA", "__const", S_REGULAR },
{ ".bss", "__DATA", "__bss", S_ZEROFILL },
{ ".tdata", "__DATA", "__thread_data", S_THREAD_LOCAL_REGULAR },
{ ".tbss", "__DATA", "__thread_bss", S_THREAD_LOCAL_ZEROFILL },
{ NULL, "__DATA", "__thread_vars", S_THREAD_LOCAL_VARIABLES },
{ NULL, "__DATA", "__thread_ptrs", S_THREAD_LOCAL_VARIABLE_POINTERS },
{ NULL, "__DATA", "__thread_init", S_THREAD_LOCAL_INIT_FUNCTION_POINTERS },
{ ".debug_abbrev", "__DWARF", "__debug_abbrev", S_ATTR_DEBUG },
{ ".debug_info", "__DWARF", "__debug_info", S_ATTR_DEBUG },
{ ".debug_line", "__DWARF", "__debug_line", S_ATTR_DEBUG },
{ ".debug_str", "__DWARF", "__debug_str", S_ATTR_DEBUG },
};

/* Section type or attribute directives */
Expand All @@ -760,6 +765,9 @@ static const struct macho_known_section_attr {
{ "mixed", S_REGULAR | S_ATTR_SOME_INSTRUCTIONS },
{ "bss", S_ZEROFILL },
{ "zerofill", S_ZEROFILL },
{ "thread_data", S_THREAD_LOCAL_REGULAR },
{ "thread_bss", S_THREAD_LOCAL_ZEROFILL },
{ "thread_zerofil", S_THREAD_LOCAL_ZEROFILL },
{ "no_dead_strip", NO_TYPE | S_ATTR_NO_DEAD_STRIP },
{ "live_support", NO_TYPE | S_ATTR_LIVE_SUPPORT },
{ "strip_static_syms", NO_TYPE | S_ATTR_STRIP_STATIC_SYMS },
Expand All @@ -777,7 +785,7 @@ lookup_known_section(const char *name, bool by_sectname)
const char *p = by_sectname ?
known_sections[i].sectname :
known_sections[i].nasmsect;
if (!strcmp(name, p))
if (p && !strcmp(name, p))
return &known_sections[i];
}
}
Expand Down Expand Up @@ -1248,7 +1256,7 @@ static void macho_calculate_sizes (void)
seg_vmsize = newaddr + s->size;

/* zerofill sections aren't actually written to the file */
if ((s->flags & SECTION_TYPE) != S_ZEROFILL) {
if ((s->flags & SECTION_TYPE) != S_ZEROFILL && (s->flags & SECTION_TYPE) != S_THREAD_LOCAL_ZEROFILL) {
/*
* LLVM/Xcode as always aligns the section data to 4
* bytes; there is a comment in the LLVM source code that
Expand Down Expand Up @@ -1330,7 +1338,7 @@ static uint32_t macho_write_segment (uint64_t offset)
/* emit section headers */
for (s = sects; s != NULL; s = s->next) {
if (s->nreloc) {
nasm_assert((s->flags & SECTION_TYPE) != S_ZEROFILL);
nasm_assert((s->flags & SECTION_TYPE) != S_ZEROFILL && (s->flags & SECTION_TYPE) != S_THREAD_LOCAL_ZEROFILL);
s->flags |= S_ATTR_LOC_RELOC;
if (s->extreloc)
s->flags |= S_ATTR_EXT_RELOC;
Expand All @@ -1353,7 +1361,7 @@ static uint32_t macho_write_segment (uint64_t offset)
fwriteptr(s->size, ofile);

/* dummy data for zerofill sections or proper values */
if ((s->flags & SECTION_TYPE) != S_ZEROFILL) {
if ((s->flags & SECTION_TYPE) != S_ZEROFILL && (s->flags & SECTION_TYPE) != S_THREAD_LOCAL_ZEROFILL) {
nasm_assert(s->pad != (uint32_t)-1);
offset += s->pad;
fwriteint32_t(offset, ofile);
Expand Down Expand Up @@ -1419,7 +1427,7 @@ static void macho_write_section (void)
} blk;

for (s = sects; s != NULL; s = s->next) {
if ((s->flags & SECTION_TYPE) == S_ZEROFILL)
if ((s->flags & SECTION_TYPE) == S_ZEROFILL || (s->flags & SECTION_TYPE) == S_THREAD_LOCAL_ZEROFILL)
continue;

/* Like a.out Mach-O references things in the data or bss
Expand Down