diff options
| author | Max Filippov <jcmvbkbc@gmail.com> | 2018-01-16 10:43:31 -0800 |
|---|---|---|
| committer | Waldemar Brodkorb <wbx@uclibc-ng.org> | 2018-01-21 11:48:00 +0000 |
| commit | 4020e24ba18e66eb8a29a0cf81d599104dfd7aa2 (patch) | |
| tree | eed66b46e47c3b04a634322df5eaeb78b71ff004 | |
| parent | b08d5b5caca499902844099ab6ddf016a7ec8e3d (diff) | |
xtensa: fix _dl_tlsdesc_dynamic
There are multiple errors in _dl_tlsdesc_dynamic:
- the reference C implementation should return pointer to the
thread-local variable, not offset from the thread pointer, because the
xtensa ABI expects TLSDESC_FN to return pointer to the TLS variable;
- addx8 used for indexing into dtv has its second and third registers in
wrong order, the index must be multiplied by 8, not the base;
- the same addx8 uses wrong base: instead of dtv it adds the offset to
the threadptr;
- the return value in the fast path is calculated as
td->tlsinfo.ti_offset - __builtin_thread_pointer, not what was
intended;
- both fast and slow paths should not subtract __builtin_thread_pointer
from the result.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
| -rw-r--r-- | ldso/ldso/xtensa/dl-tlsdesc.S | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/ldso/ldso/xtensa/dl-tlsdesc.S b/ldso/ldso/xtensa/dl-tlsdesc.S index 6f417f61a..426f2180b 100644 --- a/ldso/ldso/xtensa/dl-tlsdesc.S +++ b/ldso/ldso/xtensa/dl-tlsdesc.S @@ -39,7 +39,7 @@ END (_dl_tlsdesc_return) The assembly code that follows is a rendition of the following C code, hand-optimized a little bit. - ptrdiff_t + void * _dl_tlsdesc_dynamic(struct tlsdesc_dynamic_arg *td) { dtv_t *dtv = (dtv_t *)THREAD_DTV(); @@ -47,8 +47,8 @@ END (_dl_tlsdesc_return) && dtv[td->tlsinfo.ti_module].pointer.val != TLS_DTV_UNALLOCATED) return dtv[td->tlsinfo.ti_module].pointer.val - + td->tlsinfo.ti_offset - __builtin_thread_pointer(); - return __tls_get_addr (&td->tlsinfo) - __builtin_thread_pointer(); + + td->tlsinfo.ti_offset; + return __tls_get_addr (&td->tlsinfo); } */ @@ -65,33 +65,30 @@ HIDDEN_ENTRY (_dl_tlsdesc_dynamic) /* && dtv[td->tlsinfo.ti_module].pointer.val != TLS_DTV_UNALLOCATED) */ l32i a6, a2, TLSDESC_MODID - addx8 a6, a3, a6 + addx8 a6, a6, a4 l32i a6, a6, 0 beqi a6, -1, .Lslow /* return dtv[td->tlsinfo.ti_module].pointer.val - + td->tlsinfo.ti_offset - __builtin_thread_pointer(); */ - l32i a6, a2, TLSDESC_MODOFF - sub a2, a6, a3 + + td->tlsinfo.ti_offset; */ + l32i a5, a2, TLSDESC_MODOFF + add a2, a6, a5 abi_ret - /* return __tls_get_addr (&td->tlsinfo) - __builtin_thread_pointer(); */ + /* return __tls_get_addr (&td->tlsinfo); */ .Lslow: #if defined(__XTENSA_WINDOWED_ABI__) mov a6, a2 movi a4, __tls_get_addr callx4 a4 - sub a2, a6, a3 + mov a2, a6 retw #elif defined(__XTENSA_CALL0_ABI__) addi a1, a1, -16 s32i a0, a1, 0 - s32i a3, a1, 4 movi a0, __tls_get_addr callx0 a0 - l32i a3, a1, 4 l32i a0, a1, 0 - sub a2, a2, a3 addi a1, a1, 16 ret #else |