from rpython.rtyper.lltypesystem import lltype, rffi
from rpython.translator.tool.cbuild import ExternalCompilationInfo
from rpython.jit.backend.x86.arch import WORD

SEGMENT_FS = '\x64'
SEGMENT_GS = '\x65'

if WORD == 4:
    SEGMENT_TL = SEGMENT_GS
    _instruction = "movl %%gs:0, %0"
else:
    SEGMENT_TL = SEGMENT_FS
    _instruction = "movq %%fs:0, %0"

eci = ExternalCompilationInfo(post_include_bits=['''
#define RPY_STM_JIT  1
static long pypy__threadlocal_base(void)
{
    /* XXX ONLY LINUX WITH GCC/CLANG FOR NOW XXX */
    long result;
    asm("%s" : "=r"(result));
    return result;
}
static long pypy__get_errno_tl(void)
{
    return ((long)&errno) - pypy__threadlocal_base();
}
''' % _instruction])


threadlocal_base = rffi.llexternal(
    'pypy__threadlocal_base',
    [], lltype.Signed,
    compilation_info=eci,
    _nowrapper=True,
    ) #transactionsafe=True)

get_errno_tl = rffi.llexternal(
    'pypy__get_errno_tl',
    [], lltype.Signed,
    compilation_info=eci,
    _nowrapper=True,
    ) #transactionsafe=True)