/* Some code-gen now depends on OS major version numbers (at least). */
int generating_for_darwin_version ;
+/* For older linkers we need to emit special sections (marked 'coalesced') for
+ for weak or single-definition items. */
+static bool ld_uses_coal_sects = false;
+
/* Section names. */
section * darwin_sections[NUM_DARWIN_SECTIONS];
readonly_data_section = darwin_sections[const_section];
exception_section = darwin_sections[darwin_exception_section];
eh_frame_section = darwin_sections[darwin_eh_frame_section];
+
+ /* If our linker is new enough to coalesce weak symbols, then we
+ can just put picbase_thunks into the text section. */
+ if (! ld_uses_coal_sects )
+ darwin_sections[picbase_thunk_section] = text_section;
}
int
}
static section *
-darwin_rodata_section (int weak, bool zsize)
+darwin_rodata_section (int use_coal, bool zsize)
{
- return (weak
+ return (use_coal
? darwin_sections[const_coal_section]
: (zsize ? darwin_sections[zobj_const_section]
: darwin_sections[const_section]));
return darwin_sections[objc2_image_info_section];
else if (!strncmp (p, "V2_EHTY", 7))
- return darwin_sections[data_coal_section];
+ return ld_uses_coal_sects ? darwin_sections[data_coal_section]
+ : data_section;
else if (!strncmp (p, "V2_CSTR", 7))
return darwin_sections[objc2_constant_string_object_section];
int reloc,
unsigned HOST_WIDE_INT align)
{
- bool zsize, one, weak, ro;
+ bool zsize, one, weak, use_coal, ro;
section *base_section = NULL;
weak = (DECL_P (decl)
&& DECL_WEAK (decl)
&& !lookup_attribute ("weak_import", DECL_ATTRIBUTES (decl)));
- zsize = (DECL_P (decl)
+ zsize = (DECL_P (decl)
&& (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == CONST_DECL)
&& tree_to_uhwi (DECL_SIZE_UNIT (decl)) == 0);
- one = DECL_P (decl)
+ one = DECL_P (decl)
&& TREE_CODE (decl) == VAR_DECL
&& DECL_COMDAT_GROUP (decl);
+ use_coal = (weak || one) && ld_uses_coal_sects;
+
ro = TREE_READONLY (decl) || TREE_CONSTANT (decl) ;
switch (categorize_decl_for_section (decl, reloc))
case SECCAT_RODATA:
case SECCAT_SRODATA:
- base_section = darwin_rodata_section (weak, zsize);
+ base_section = darwin_rodata_section (use_coal, zsize);
break;
case SECCAT_RODATA_MERGE_STR:
case SECCAT_DATA_REL_RO_LOCAL:
case SECCAT_SDATA:
case SECCAT_TDATA:
- if (weak || one)
+ if (use_coal)
{
if (ro)
base_section = darwin_sections[const_data_coal_section];
case SECCAT_BSS:
case SECCAT_SBSS:
case SECCAT_TBSS:
- if (weak || one)
+ if (use_coal)
base_section = darwin_sections[data_coal_section];
else
{
static void
darwin_emit_weak_or_comdat (FILE *fp, tree decl, const char *name,
unsigned HOST_WIDE_INT size,
+ bool use_coal,
unsigned int align)
{
- /* Since the sections used here are coalesed, they will not be eligible
- for section anchors, and therefore we don't need to break that out. */
+ /* Since the sections used here are coalesced, they will not be eligible
+ for section anchors, and therefore we don't need to break that out.
+ CHECKME: for modern linker on PowerPC. */
if (TREE_READONLY (decl) || TREE_CONSTANT (decl))
- switch_to_section (darwin_sections[const_data_coal_section]);
+ switch_to_section (use_coal ? darwin_sections[const_data_coal_section]
+ : darwin_sections[const_data_section]);
else
- switch_to_section (darwin_sections[data_coal_section]);
+ switch_to_section (use_coal ? darwin_sections[data_coal_section]
+ : data_section);
/* To be consistent, we'll allow darwin_asm_declare_object_name to assemble
the align info for zero-sized items... but do it here otherwise. */
{
/* Weak or COMDAT objects are put in mergeable sections. */
darwin_emit_weak_or_comdat (fp, decl, name, size,
- DECL_ALIGN (decl));
+ ld_uses_coal_sects, DECL_ALIGN (decl));
return;
}
{
/* Weak or COMDAT objects are put in mergable sections. */
darwin_emit_weak_or_comdat (fp, decl, name, size,
- DECL_ALIGN (decl));
+ ld_uses_coal_sects, DECL_ALIGN (decl));
return;
}
{
/* Weak or COMDAT objects are put in mergable sections. */
darwin_emit_weak_or_comdat (fp, decl, name, size,
- DECL_ALIGN (decl));
+ ld_uses_coal_sects, DECL_ALIGN (decl));
return;
}
/* Earlier versions are not specifically accounted, until required. */
}
+ /* Older Darwin ld could not coalesce weak entities without them being
+ placed in special sections. */
+ if (darwin_target_linker
+ && (strverscmp (darwin_target_linker, MIN_LD64_NO_COAL_SECTS) < 0))
+ ld_uses_coal_sects = true;
+
/* In principle, this should be c-family only. However, we really need to
set sensible defaults for LTO as well, since the section selection stuff
should check for correctness re. the ABI. TODO: check and provide the
bool startup, bool exit)
{
/* Decide if we need to put this in a coalescable section. */
- bool weak = (decl
+ bool weak = (decl
&& DECL_WEAK (decl)
&& (!DECL_ATTRIBUTES (decl)
|| !lookup_attribute ("weak_import",
DECL_ATTRIBUTES (decl))));
+ bool use_coal = weak && ld_uses_coal_sects;
/* If there is a specified section name, we should not be trying to
override. */
if (decl && DECL_SECTION_NAME (decl) != NULL)
/* We always put unlikely executed stuff in the cold section. */
if (freq == NODE_FREQUENCY_UNLIKELY_EXECUTED)
- return (weak) ? darwin_sections[text_cold_coal_section]
- : darwin_sections[text_cold_section];
+ return (use_coal) ? darwin_sections[text_cold_coal_section]
+ : darwin_sections[text_cold_section];
/* If we have LTO *and* feedback information, then let LTO handle
the function ordering, it makes a better job (for normal, hot,
/* Non-cold startup code should go to startup subsection. */
if (startup)
- return (weak) ? darwin_sections[text_startup_coal_section]
- : darwin_sections[text_startup_section];
+ return (use_coal) ? darwin_sections[text_startup_coal_section]
+ : darwin_sections[text_startup_section];
/* Similarly for exit. */
if (exit)
- return (weak) ? darwin_sections[text_exit_coal_section]
- : darwin_sections[text_exit_section];
+ return (use_coal) ? darwin_sections[text_exit_coal_section]
+ : darwin_sections[text_exit_section];
/* Place hot code. */
if (freq == NODE_FREQUENCY_HOT)
- return (weak) ? darwin_sections[text_hot_coal_section]
- : darwin_sections[text_hot_section];
+ return (use_coal) ? darwin_sections[text_hot_coal_section]
+ : darwin_sections[text_hot_section];
/* Otherwise, default to the 'normal' non-reordered sections. */
default_function_sections:
- return (weak) ? darwin_sections[text_coal_section]
- : text_section;
+ return (use_coal) ? darwin_sections[text_coal_section]
+ : text_section;
}
/* When a function is partitioned between sections, we need to insert a label
projects / gcc.git / commitdiff