mirrors/binutils-gdb
1
0
Fork 0
mirror of https://sourceware.org/git/binutils-gdb.git synced 2024-11-26 19:44:11 +08:00
Code Issues Actions Packages Projects Releases Wiki Activity

PR32387 ppc64 TLS optimization bug with -fno-plt code

Browse Source 
The inline plt code emitted by gcc is incompatible with the
linker/ld.so --tls-get-addr-optimize scheme.  This is the runtime
optimisation where the first call to __tls_get_addr results in
__tls_get_addr updating the tls_index pair, then the special linker
stub using that to short-circuit second and subsequent calls for a
given tls symbol.  Enabled by default when the linker sees
__tls_get_addr_opt is preseent, and enabled in ld.so when DT_PPC64_OPT
has PPC64_OPT_TLS set.  Note that this is distinct from link-time tls
optimisation.

	PR 32387
	* elf64-ppc.c (ppc64_elf_check_relocs): Disable tls_get_addr_opt
	on detecting inline plt calls to __tls_get_addr.
This commit is contained in:
Alan Modra 2024-11-26 08:24:19 +10:30
parent ed732554ca
commit 1686dc7079
1 changed files with 9 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
bfd/elf64-ppc.c
View File

@ -4915,6 +4915,15 @@ ppc64_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
tls_type = 0;
switch (r_type)
{
case R_PPC64_PLTSEQ:
case R_PPC64_PLTSEQ_NOTOC:
/* Inline plt call code emitted by gcc doesn't support
modifying the tls_index words to short-circuit
__tls_get_addr calls. See PR32387. */
if (h != NULL && (h == tga || h == dottga))
htab->params->tls_get_addr_opt = 0;
break;
case R_PPC64_TLSGD:
case R_PPC64_TLSLD:
/* These special tls relocs tie a call to __tls_get_addr with