/usr/lib/gcc/x86_64-linux-gnu/6/include/d/rt/sections_elf_shared.d is in libgphobos-6-dev 6.4.0-17ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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* Written in the D programming language.
* This module provides ELF-specific support for sections with shared libraries.
*
* Copyright: Copyright Martin Nowak 2012-2013.
* License: $(WEB www.boost.org/LICENSE_1_0.txt, Boost License 1.0).
* Authors: Martin Nowak
* Source: $(DRUNTIMESRC src/rt/_sections_linux.d)
*/
module rt.sections_elf_shared;
version (CRuntime_Glibc) enum SharedELF = true;
else version (FreeBSD) enum SharedELF = true;
else enum SharedELF = false;
static if (SharedELF):
// debug = PRINTF;
import core.memory;
import core.stdc.stdio;
import core.stdc.stdlib : calloc, exit, free, malloc, EXIT_FAILURE;
import core.stdc.string : strlen;
version (linux)
{
import core.sys.linux.dlfcn;
import core.sys.linux.elf;
import core.sys.linux.link;
}
else version (FreeBSD)
{
import core.sys.freebsd.dlfcn;
import core.sys.freebsd.sys.elf;
import core.sys.freebsd.sys.link_elf;
}
else
{
static assert(0, "unimplemented");
}
import core.sys.posix.pthread;
import rt.deh;
import rt.dmain2;
import rt.minfo;
import rt.util.container.array;
import rt.util.container.hashtab;
alias DSO SectionGroup;
struct DSO
{
static int opApply(scope int delegate(ref DSO) dg)
{
foreach (dso; _loadedDSOs)
{
if (auto res = dg(*dso))
return res;
}
return 0;
}
static int opApplyReverse(scope int delegate(ref DSO) dg)
{
foreach_reverse (dso; _loadedDSOs)
{
if (auto res = dg(*dso))
return res;
}
return 0;
}
@property immutable(ModuleInfo*)[] modules() const
{
return _moduleGroup.modules;
}
@property ref inout(ModuleGroup) moduleGroup() inout
{
return _moduleGroup;
}
@property immutable(FuncTable)[] ehTables() const
{
return _ehTables[];
}
@property inout(void[])[] gcRanges() inout
{
return _gcRanges[];
}
private:
invariant()
{
assert(_moduleGroup.modules.length);
assert(_tlsMod || !_tlsSize);
}
immutable(FuncTable)[] _ehTables;
ModuleGroup _moduleGroup;
Array!(void[]) _gcRanges;
size_t _tlsMod;
size_t _tlsSize;
version (Shared)
{
Array!(void[]) _codeSegments; // array of code segments
Array!(DSO*) _deps; // D libraries needed by this DSO
void* _handle; // corresponding handle
}
}
/****
* Boolean flag set to true while the runtime is initialized.
*/
__gshared bool _isRuntimeInitialized;
version (FreeBSD) private __gshared void* dummy_ref;
/****
* Gets called on program startup just before GC is initialized.
*/
void initSections()
{
_isRuntimeInitialized = true;
// reference symbol to support weak linkage
version (FreeBSD) dummy_ref = &_d_dso_registry;
}
/***
* Gets called on program shutdown just after GC is terminated.
*/
void finiSections()
{
_isRuntimeInitialized = false;
}
alias ScanDG = void delegate(void* pbeg, void* pend) nothrow;
version (Shared)
{
/***
* Called once per thread; returns array of thread local storage ranges
*/
Array!(ThreadDSO)* initTLSRanges()
{
return &_loadedDSOs;
}
void finiTLSRanges(Array!(ThreadDSO)* tdsos)
{
tdsos.reset();
}
void scanTLSRanges(Array!(ThreadDSO)* tdsos, scope ScanDG dg) nothrow
{
foreach (ref tdso; *tdsos)
dg(tdso._tlsRange.ptr, tdso._tlsRange.ptr + tdso._tlsRange.length);
}
// interface for core.thread to inherit loaded libraries
void* pinLoadedLibraries() nothrow
{
auto res = cast(Array!(ThreadDSO)*)calloc(1, Array!(ThreadDSO).sizeof);
res.length = _loadedDSOs.length;
foreach (i, ref tdso; _loadedDSOs)
{
(*res)[i] = tdso;
if (tdso._addCnt)
{
// Increment the dlopen ref for explicitly loaded libraries to pin them.
.dlopen(linkMapForHandle(tdso._pdso._handle).l_name, RTLD_LAZY) !is null || assert(0);
(*res)[i]._addCnt = 1; // new array takes over the additional ref count
}
}
return res;
}
void unpinLoadedLibraries(void* p) nothrow
{
auto pary = cast(Array!(ThreadDSO)*)p;
// In case something failed we need to undo the pinning.
foreach (ref tdso; *pary)
{
if (tdso._addCnt)
{
auto handle = tdso._pdso._handle;
handle !is null || assert(0);
.dlclose(handle);
}
}
pary.reset();
.free(pary);
}
// Called before TLS ctors are ran, copy over the loaded libraries
// of the parent thread.
void inheritLoadedLibraries(void* p)
{
assert(_loadedDSOs.empty);
_loadedDSOs.swap(*cast(Array!(ThreadDSO)*)p);
.free(p);
}
// Called after all TLS dtors ran, decrements all remaining dlopen refs.
void cleanupLoadedLibraries()
{
foreach (ref tdso; _loadedDSOs)
{
if (tdso._addCnt == 0) continue;
auto handle = tdso._pdso._handle;
handle !is null || assert(0);
for (; tdso._addCnt > 0; --tdso._addCnt)
.dlclose(handle);
}
_loadedDSOs.reset();
}
}
else
{
/***
* Called once per thread; returns array of thread local storage ranges
*/
Array!(void[])* initTLSRanges()
{
return &_tlsRanges;
}
void finiTLSRanges(Array!(void[])* rngs)
{
rngs.reset();
}
void scanTLSRanges(Array!(void[])* rngs, scope ScanDG dg) nothrow
{
foreach (rng; *rngs)
dg(rng.ptr, rng.ptr + rng.length);
}
}
private:
// start of linked list for ModuleInfo references
version (FreeBSD) deprecated extern (C) __gshared void* _Dmodule_ref;
version (Shared)
{
/*
* Array of thread local DSO metadata for all libraries loaded and
* initialized in this thread.
*
* Note:
* A newly spawned thread will inherit these libraries.
* Note:
* We use an array here to preserve the order of
* initialization. If that became a performance issue, we
* could use a hash table and enumerate the DSOs during
* loading so that the hash table values could be sorted when
* necessary.
*/
struct ThreadDSO
{
DSO* _pdso;
static if (_pdso.sizeof == 8) uint _refCnt, _addCnt;
else static if (_pdso.sizeof == 4) ushort _refCnt, _addCnt;
else static assert(0, "unimplemented");
void[] _tlsRange;
alias _pdso this;
}
Array!(ThreadDSO) _loadedDSOs;
/*
* Set to true during rt_loadLibrary/rt_unloadLibrary calls.
*/
bool _rtLoading;
/*
* Hash table to map link_map* to corresponding DSO*.
* The hash table is protected by a Mutex.
*/
__gshared pthread_mutex_t _handleToDSOMutex;
__gshared HashTab!(void*, DSO*) _handleToDSO;
}
else
{
/*
* Static DSOs loaded by the runtime linker. This includes the
* executable. These can't be unloaded.
*/
__gshared Array!(DSO*) _loadedDSOs;
/*
* Thread local array that contains TLS memory ranges for each
* library initialized in this thread.
*/
Array!(void[]) _tlsRanges;
enum _rtLoading = false;
}
///////////////////////////////////////////////////////////////////////////////
// Compiler to runtime interface.
///////////////////////////////////////////////////////////////////////////////
import gcc.config;
static assert(Minfo_Bracketing, "Can't use _d_dso_registry interface");
/*
* This data structure is generated by the compiler, and then passed to
* _d_dso_registry().
*/
struct CompilerDSOData
{
size_t _version; // currently 1
void** _slot; // can be used to store runtime data
immutable(object.ModuleInfo*)* _minfo_beg, _minfo_end; // array of modules in this object file
immutable(rt.deh.FuncTable)* _deh_beg, _deh_end; // array of exception handling data
}
T[] toRange(T)(T* beg, T* end) { return beg[0 .. end - beg]; }
/* For each shared library and executable, the compiler generates code that
* sets up CompilerDSOData and calls _d_dso_registry().
* A pointer to that code is inserted into both the .ctors and .dtors
* segment so it gets called by the loader on startup and shutdown.
*/
extern(C) void _d_dso_registry(CompilerDSOData* data)
{
// only one supported currently
data._version >= 1 || assert(0, "corrupt DSO data version");
// no backlink => register
if (*data._slot is null)
{
if (_loadedDSOs.empty) initLocks(); // first DSO
DSO* pdso = cast(DSO*).calloc(1, DSO.sizeof);
assert(typeid(DSO).init().ptr is null);
*data._slot = pdso; // store backlink in library record
pdso._moduleGroup = ModuleGroup(toRange(data._minfo_beg, data._minfo_end));
pdso._ehTables = toRange(data._deh_beg, data._deh_end);
dl_phdr_info info = void;
findDSOInfoForAddr(data._slot, &info) || assert(0);
scanSegments(info, pdso);
checkModuleCollisions(info, pdso._moduleGroup.modules);
version (Shared)
{
// the first loaded DSO is druntime itself
assert(!_loadedDSOs.empty ||
/* We need a local symbol (rt_get_bss_start) or the function
* pointer might be a PLT address in the executable.
* data._slot is already local in the shared library
*/
handleForAddr(&rt_get_bss_start) == handleForAddr(data._slot));
getDependencies(info, pdso._deps);
pdso._handle = handleForAddr(data._slot);
setDSOForHandle(pdso, pdso._handle);
if (!_rtLoading)
{
/* This DSO was not loaded by rt_loadLibrary which
* happens for all dependencies of an executable or
* the first dlopen call from a C program.
* In this case we add the DSO to the _loadedDSOs of this
* thread with a refCnt of 1 and call the TlsCtors.
*/
immutable ushort refCnt = 1, addCnt = 0;
auto tlsRng = getTLSRange(pdso._tlsMod, pdso._tlsSize);
_loadedDSOs.insertBack(ThreadDSO(pdso, refCnt, addCnt, tlsRng));
}
}
else
{
foreach (p; _loadedDSOs) assert(p !is pdso);
_loadedDSOs.insertBack(pdso);
_tlsRanges.insertBack(getTLSRange(pdso._tlsMod, pdso._tlsSize));
}
// don't initialize modules before rt_init was called (see Bugzilla 11378)
if (_isRuntimeInitialized)
{
registerGCRanges(pdso);
// rt_loadLibrary will run tls ctors, so do this only for dlopen
immutable runTlsCtors = !_rtLoading;
runModuleConstructors(pdso, runTlsCtors);
}
}
// has backlink => unregister
else
{
DSO* pdso = cast(DSO*)*data._slot;
*data._slot = null;
// don't finalizes modules after rt_term was called (see Bugzilla 11378)
if (_isRuntimeInitialized)
{
// rt_unloadLibrary already ran tls dtors, so do this only for dlclose
immutable runTlsDtors = !_rtLoading;
runModuleDestructors(pdso, runTlsDtors);
unregisterGCRanges(pdso);
// run finalizers after module dtors (same order as in rt_term)
version (Shared) runFinalizers(pdso);
}
version (Shared)
{
if (!_rtLoading)
{
/* This DSO was not unloaded by rt_unloadLibrary so we
* have to remove it from _loadedDSOs here.
*/
foreach (i, ref tdso; _loadedDSOs)
{
if (tdso._pdso == pdso)
{
_loadedDSOs.remove(i);
break;
}
}
}
assert(pdso._handle == handleForAddr(data._slot));
unsetDSOForHandle(pdso, pdso._handle);
pdso._handle = null;
}
else
{
// static DSOs are unloaded in reverse order
assert(pdso._tlsSize == _tlsRanges.back.length);
_tlsRanges.popBack();
assert(pdso == _loadedDSOs.back);
_loadedDSOs.popBack();
}
freeDSO(pdso);
if (_loadedDSOs.empty) finiLocks(); // last DSO
}
}
///////////////////////////////////////////////////////////////////////////////
// dynamic loading
///////////////////////////////////////////////////////////////////////////////
// Shared D libraries are only supported when linking against a shared druntime library.
version (Shared)
{
ThreadDSO* findThreadDSO(DSO* pdso)
{
foreach (ref tdata; _loadedDSOs)
if (tdata._pdso == pdso) return &tdata;
return null;
}
void incThreadRef(DSO* pdso, bool incAdd)
{
if (auto tdata = findThreadDSO(pdso)) // already initialized
{
if (incAdd && ++tdata._addCnt > 1) return;
++tdata._refCnt;
}
else
{
foreach (dep; pdso._deps)
incThreadRef(dep, false);
immutable ushort refCnt = 1, addCnt = incAdd ? 1 : 0;
auto tlsRng = getTLSRange(pdso._tlsMod, pdso._tlsSize);
_loadedDSOs.insertBack(ThreadDSO(pdso, refCnt, addCnt, tlsRng));
pdso._moduleGroup.runTlsCtors();
}
}
void decThreadRef(DSO* pdso, bool decAdd)
{
auto tdata = findThreadDSO(pdso);
tdata !is null || assert(0);
!decAdd || tdata._addCnt > 0 || assert(0, "Mismatching rt_unloadLibrary call.");
if (decAdd && --tdata._addCnt > 0) return;
if (--tdata._refCnt > 0) return;
pdso._moduleGroup.runTlsDtors();
foreach (i, ref td; _loadedDSOs)
if (td._pdso == pdso) _loadedDSOs.remove(i);
foreach (dep; pdso._deps)
decThreadRef(dep, false);
}
extern(C) void* rt_loadLibrary(const char* name)
{
immutable save = _rtLoading;
_rtLoading = true;
scope (exit) _rtLoading = save;
auto handle = .dlopen(name, RTLD_LAZY);
if (handle is null) return null;
// if it's a D library
if (auto pdso = dsoForHandle(handle))
incThreadRef(pdso, true);
return handle;
}
extern(C) int rt_unloadLibrary(void* handle)
{
if (handle is null) return false;
immutable save = _rtLoading;
_rtLoading = true;
scope (exit) _rtLoading = save;
// if it's a D library
if (auto pdso = dsoForHandle(handle))
decThreadRef(pdso, true);
return .dlclose(handle) == 0;
}
}
///////////////////////////////////////////////////////////////////////////////
// helper functions
///////////////////////////////////////////////////////////////////////////////
void initLocks()
{
version (Shared)
!pthread_mutex_init(&_handleToDSOMutex, null) || assert(0);
}
void finiLocks()
{
version (Shared)
!pthread_mutex_destroy(&_handleToDSOMutex) || assert(0);
}
void runModuleConstructors(DSO* pdso, bool runTlsCtors)
{
pdso._moduleGroup.sortCtors();
pdso._moduleGroup.runCtors();
if (runTlsCtors) pdso._moduleGroup.runTlsCtors();
}
void runModuleDestructors(DSO* pdso, bool runTlsDtors)
{
if (runTlsDtors) pdso._moduleGroup.runTlsDtors();
pdso._moduleGroup.runDtors();
}
void registerGCRanges(DSO* pdso)
{
foreach (rng; pdso._gcRanges)
GC.addRange(rng.ptr, rng.length);
}
void unregisterGCRanges(DSO* pdso)
{
foreach (rng; pdso._gcRanges)
GC.removeRange(rng.ptr);
}
version (Shared) void runFinalizers(DSO* pdso)
{
foreach (seg; pdso._codeSegments)
GC.runFinalizers(seg);
}
void freeDSO(DSO* pdso)
{
pdso._gcRanges.reset();
version (Shared) pdso._codeSegments.reset();
.free(pdso);
}
version (Shared)
{
nothrow:
link_map* linkMapForHandle(void* handle)
{
link_map* map;
dlinfo(handle, RTLD_DI_LINKMAP, &map) == 0 || assert(0);
return map;
}
DSO* dsoForHandle(void* handle)
{
DSO* pdso;
!pthread_mutex_lock(&_handleToDSOMutex) || assert(0);
if (auto ppdso = handle in _handleToDSO)
pdso = *ppdso;
!pthread_mutex_unlock(&_handleToDSOMutex) || assert(0);
return pdso;
}
void setDSOForHandle(DSO* pdso, void* handle)
{
!pthread_mutex_lock(&_handleToDSOMutex) || assert(0);
assert(handle !in _handleToDSO);
_handleToDSO[handle] = pdso;
!pthread_mutex_unlock(&_handleToDSOMutex) || assert(0);
}
void unsetDSOForHandle(DSO* pdso, void* handle)
{
!pthread_mutex_lock(&_handleToDSOMutex) || assert(0);
assert(_handleToDSO[handle] == pdso);
_handleToDSO.remove(handle);
!pthread_mutex_unlock(&_handleToDSOMutex) || assert(0);
}
void getDependencies(in ref dl_phdr_info info, ref Array!(DSO*) deps)
{
// get the entries of the .dynamic section
ElfW!"Dyn"[] dyns;
foreach (ref phdr; info.dlpi_phdr[0 .. info.dlpi_phnum])
{
if (phdr.p_type == PT_DYNAMIC)
{
auto p = cast(ElfW!"Dyn"*)(info.dlpi_addr + (phdr.p_vaddr & ~(size_t.sizeof - 1)));
dyns = p[0 .. phdr.p_memsz / ElfW!"Dyn".sizeof];
break;
}
}
// find the string table which contains the sonames
const(char)* strtab;
foreach (dyn; dyns)
{
if (dyn.d_tag == DT_STRTAB)
{
version (linux)
strtab = cast(const(char)*)dyn.d_un.d_ptr;
else version (FreeBSD)
strtab = cast(const(char)*)(info.dlpi_addr + dyn.d_un.d_ptr); // relocate
else
static assert(0, "unimplemented");
break;
}
}
foreach (dyn; dyns)
{
immutable tag = dyn.d_tag;
if (!(tag == DT_NEEDED || tag == DT_AUXILIARY || tag == DT_FILTER))
continue;
// soname of the dependency
auto name = strtab + dyn.d_un.d_val;
// get handle without loading the library
auto handle = handleForName(name);
// the runtime linker has already loaded all dependencies
if (handle is null) assert(0);
// if it's a D library
if (auto pdso = dsoForHandle(handle))
deps.insertBack(pdso); // append it to the dependencies
}
}
void* handleForName(const char* name)
{
auto handle = .dlopen(name, RTLD_NOLOAD | RTLD_LAZY);
if (handle !is null) .dlclose(handle); // drop reference count
return handle;
}
}
///////////////////////////////////////////////////////////////////////////////
// Elf program header iteration
///////////////////////////////////////////////////////////////////////////////
/************
* Scan segments in Linux dl_phdr_info struct and store
* the TLS and writeable data segments in *pdso.
*/
void scanSegments(in ref dl_phdr_info info, DSO* pdso)
{
foreach (ref phdr; info.dlpi_phdr[0 .. info.dlpi_phnum])
{
switch (phdr.p_type)
{
case PT_LOAD:
if (phdr.p_flags & PF_W) // writeable data segment
{
auto beg = cast(void*)(info.dlpi_addr + (phdr.p_vaddr & ~(size_t.sizeof - 1)));
pdso._gcRanges.insertBack(beg[0 .. phdr.p_memsz]);
}
version (Shared) if (phdr.p_flags & PF_X) // code segment
{
auto beg = cast(void*)(info.dlpi_addr + (phdr.p_vaddr & ~(size_t.sizeof - 1)));
pdso._codeSegments.insertBack(beg[0 .. phdr.p_memsz]);
}
break;
case PT_TLS: // TLS segment
assert(!pdso._tlsSize); // is unique per DSO
pdso._tlsMod = info.dlpi_tls_modid;
pdso._tlsSize = phdr.p_memsz;
break;
default:
break;
}
}
}
/**************************
* Input:
* result where the output is to be written; dl_phdr_info is a Linux struct
* Returns:
* true if found, and *result is filled in
* References:
* http://linux.die.net/man/3/dl_iterate_phdr
*/
version (linux) bool findDSOInfoForAddr(in void* addr, dl_phdr_info* result=null) nothrow @nogc
{
static struct DG { const(void)* addr; dl_phdr_info* result; }
extern(C) int callback(dl_phdr_info* info, size_t sz, void* arg) nothrow @nogc
{
auto p = cast(DG*)arg;
if (findSegmentForAddr(*info, p.addr))
{
if (p.result !is null) *p.result = *info;
return 1; // break;
}
return 0; // continue iteration
}
auto dg = DG(addr, result);
/* Linux function that walks through the list of an application's shared objects and
* calls 'callback' once for each object, until either all shared objects
* have been processed or 'callback' returns a nonzero value.
*/
return dl_iterate_phdr(&callback, &dg) != 0;
}
else version (FreeBSD) bool findDSOInfoForAddr(in void* addr, dl_phdr_info* result=null) nothrow @nogc
{
return !!_rtld_addr_phdr(addr, result);
}
/*********************************
* Determine if 'addr' lies within shared object 'info'.
* If so, return true and fill in 'result' with the corresponding ELF program header.
*/
bool findSegmentForAddr(in ref dl_phdr_info info, in void* addr, ElfW!"Phdr"* result=null) nothrow @nogc
{
if (addr < cast(void*)info.dlpi_addr) // less than base address of object means quick reject
return false;
foreach (ref phdr; info.dlpi_phdr[0 .. info.dlpi_phnum])
{
auto beg = cast(void*)(info.dlpi_addr + (phdr.p_vaddr & ~(size_t.sizeof - 1)));
if (cast(size_t)(addr - beg) < phdr.p_memsz)
{
if (result !is null) *result = phdr;
return true;
}
}
return false;
}
version (linux) import core.sys.linux.errno : program_invocation_name;
// should be in core.sys.freebsd.stdlib
version (FreeBSD) extern(C) const(char)* getprogname() nothrow @nogc;
@property const(char)* progname() nothrow @nogc
{
version (linux) return program_invocation_name;
version (FreeBSD) return getprogname();
}
nothrow
const(char)[] dsoName(const char* dlpi_name)
{
// the main executable doesn't have a name in its dlpi_name field
const char* p = dlpi_name[0] != 0 ? dlpi_name : progname;
return p[0 .. strlen(p)];
}
extern(C)
{
void* rt_get_bss_start() @nogc nothrow;
void* rt_get_end() @nogc nothrow;
}
nothrow
void checkModuleCollisions(in ref dl_phdr_info info, in immutable(ModuleInfo)*[] modules)
in { assert(modules.length); }
body
{
immutable(ModuleInfo)* conflicting;
auto bss_start = rt_get_bss_start();
immutable bss_size = rt_get_end() - bss_start;
assert(bss_size >= 0);
foreach (m; modules)
{
auto addr = cast(const(void*))m;
if (cast(size_t)(addr - bss_start) < cast(size_t)bss_size)
{
// Module is in .bss of the exe because it was copy relocated
}
else if (!findSegmentForAddr(info, addr))
{
// Module is in another DSO
conflicting = m;
break;
}
}
if (conflicting !is null)
{
dl_phdr_info other=void;
findDSOInfoForAddr(conflicting, &other) || assert(0);
auto modname = conflicting.name;
auto loading = dsoName(info.dlpi_name);
auto existing = dsoName(other.dlpi_name);
fprintf(stderr, "Fatal Error while loading '%.*s':\n\tThe module '%.*s' is already defined in '%.*s'.\n",
cast(int)loading.length, loading.ptr,
cast(int)modname.length, modname.ptr,
cast(int)existing.length, existing.ptr);
assert(0);
}
}
/**************************
* Input:
* addr an internal address of a DSO
* Returns:
* the dlopen handle for that DSO or null if addr is not within a loaded DSO
*/
version (Shared) void* handleForAddr(void* addr)
{
Dl_info info = void;
if (dladdr(addr, &info) != 0)
return handleForName(info.dli_fname);
return null;
}
///////////////////////////////////////////////////////////////////////////////
// TLS module helper
///////////////////////////////////////////////////////////////////////////////
/*
* Returns: the TLS memory range for a given module and the calling
* thread or null if that module has no TLS.
*
* Note: This will cause the TLS memory to be eagerly allocated.
*/
struct tls_index
{
size_t ti_module;
size_t ti_offset;
}
extern(C) void* __tls_get_addr(tls_index* ti);
/* The dynamic thread vector (DTV) pointers may point 0x8000 past the start of
* each TLS block. This is at least true for PowerPC and Mips platforms.
* See: https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/powerpc/dl-tls.h;h=f7cf6f96ebfb505abfd2f02be0ad0e833107c0cd;hb=HEAD#l34
* https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/mips/dl-tls.h;h=93a6dc050cb144b9f68b96fb3199c60f5b1fcd18;hb=HEAD#l32
*/
version(X86)
enum TLS_DTV_OFFSET = 0x;
else version(X86_64)
enum TLS_DTV_OFFSET = 0x;
else version(ARM)
enum TLS_DTV_OFFSET = 0x;
else version(AArch64)
enum TLS_DTV_OFFSET = 0x;
else version(SPARC)
enum TLS_DTV_OFFSET = 0x;
else version(SPARC64)
enum TLS_DTV_OFFSET = 0x;
else version(PPC)
enum TLS_DTV_OFFSET = 0x8000;
else version(PPC64)
enum TLS_DTV_OFFSET = 0x8000;
else version(MIPS)
enum TLS_DTV_OFFSET = 0x8000;
else version(MIPS64)
enum TLS_DTV_OFFSET = 0x8000;
else
static assert( false, "Platform not supported." );
void[] getTLSRange(size_t mod, size_t sz)
{
if (mod == 0)
return null;
// base offset
auto ti = tls_index(mod, 0);
return (__tls_get_addr(&ti)-TLS_DTV_OFFSET)[0 .. sz];
}
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