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| author | Alan Modra <amodra@gmail.com> | 2015-01-29 11:09:55 +1030 |
|---|---|---|
| committer | Alan Modra <amodra@gmail.com> | 2015-01-29 13:13:02 +1030 |
| commit | b86ac8e3a5a3117696b1760003b8e09ed13f1de9 (patch) | |
| tree | 62ef24abc3d0ef13113729ea6f1ae626e556e4af /ld/testsuite/ld-powerpc/tlsld32.s | |
| parent | 912ae7dd0fa4658133d4fb77954a57c8548c37d6 (diff) | |
| download | gdb-b86ac8e3a5a3117696b1760003b8e09ed13f1de9.zip gdb-b86ac8e3a5a3117696b1760003b8e09ed13f1de9.tar.gz gdb-b86ac8e3a5a3117696b1760003b8e09ed13f1de9.tar.bz2 | |
Correct PowerPC64 local-dynamic TLS linker optimization
The linker hardcoded r3 into a local-dynamic to local-exec TLS
optimization sequence. This is normally the case since r3 is required
as a parameter to (the optimized out) __tls_get_addr call. However,
it is possible for a compiler, LLVM in this case, to set up the
parameter value in another register then copy it to r3 before the
call.
When fixing this problem, I noticed that ppc32 had another bug when
optimizing away one of the TLS insns to a nop.
The patch also tidies a mask used by global-dynamic to initial-exec
TLS optimization, to just select the fields needed. Leaving the
offset in the instruction wasn't a bug since it will be overwritten
anyway.
bfd/
* elf64-ppc.c (ppc64_elf_relocate_section): Correct GOT_TLSLD
optimization. Tidy mask for GOT_TLSGD optimization.
* elf32-ppc.c (ppc_elf_relocate_section): Likewise. Correct
location of nop zapping high insn too.
ld/testsuite/
* ld-powerpc/tlsld.d, * ld-powerpc/tlsld.s: New test.
* ld-powerpc/tlsld32.d, * ld-powerpc/tlsld32.s: New test.
* ld-powerpc/powerpc.exp: Run them. Move tocvar and tocnovar.
Diffstat (limited to 'ld/testsuite/ld-powerpc/tlsld32.s')
| -rw-r--r-- | ld/testsuite/ld-powerpc/tlsld32.s | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/ld/testsuite/ld-powerpc/tlsld32.s b/ld/testsuite/ld-powerpc/tlsld32.s new file mode 100644 index 0000000..f5561d4 --- /dev/null +++ b/ld/testsuite/ld-powerpc/tlsld32.s @@ -0,0 +1,43 @@ + .text + .globl _start +_start: + addis 3,31,PrettyStackTraceHead@got@tlsld@ha + addi 29,3,PrettyStackTraceHead@got@tlsld@l + mr 3,29 + bl __tls_get_addr(PrettyStackTraceHead@tlsld) + addis 3,3,PrettyStackTraceHead@dtprel@ha + lwz 3,PrettyStackTraceHead@dtprel@l(3) + nop + nop + + addi 29,31,PrettyStackTraceHead@got@tlsld + mr 3,29 + bl __tls_get_addr(PrettyStackTraceHead@tlsld) + lwz 3,PrettyStackTraceHead@dtprel(3) + nop + nop + nop + nop + + addis 3,31,PrettyStackTraceHead@got@tlsgd@ha + addi 29,3,PrettyStackTraceHead@got@tlsgd@l + mr 3,29 + bl __tls_get_addr(PrettyStackTraceHead@tlsgd) + lwz 3,0(3) + nop + nop + nop + + addi 29,31,PrettyStackTraceHead@got@tlsgd + mr 3,29 + bl __tls_get_addr(PrettyStackTraceHead@tlsgd) + lwz 3,0(3) + nop + nop + nop + nop + + .section ".tbss","awT",@nobits + .align 2 +PrettyStackTraceHead: + .space 4 |