diff options
Diffstat (limited to 'sysdeps/sparc/sparc64/dl-machine.h')
| -rw-r--r-- | sysdeps/sparc/sparc64/dl-machine.h | 42 |
1 files changed, 30 insertions, 12 deletions
diff --git a/sysdeps/sparc/sparc64/dl-machine.h b/sysdeps/sparc/sparc64/dl-machine.h index b4785c74cc..c420bbdf86 100644 --- a/sysdeps/sparc/sparc64/dl-machine.h +++ b/sysdeps/sparc/sparc64/dl-machine.h @@ -49,19 +49,37 @@ elf_machine_dynamic (void) static inline Elf64_Addr elf_machine_load_address (void) { - register Elf64_Addr elf_pic_register __asm__("%l7"); - Elf64_Addr pc, la; - - /* Utilize the fact that a local .got entry will be partially - initialized at startup awaiting its RELATIVE fixup. */ - - __asm("sethi %%hi(.Load_address), %1\n" - ".Load_address:\n\t" - "rd %%pc, %0\n\t" - "or %1, %%lo(.Load_address), %1\n\t" - : "=r"(pc), "=r"(la)); + register Elf64_Addr *elf_pic_register __asm__("%l7"); - return pc - *(Elf64_Addr *)(elf_pic_register + la); + /* We used to utilize the fact that a local .got entry will + be partially initialized at startup awaiting its RELATIVE + fixup: + + Elf64_Addr pc, la; + + __asm("sethi %%hi(.Load_address), %1\n" + ".Load_address:\n\t" + "rd %%pc, %0\n\t" + "or %1, %%lo(.Load_address), %1\n\t" + : "=r"(pc), "=r"(la)); + + return pc - *(Elf64_Addr *)(elf_pic_register + la); + + Unfortunately as binutils tries to work around Solaris + dynamic linker bug which resolves R_SPARC_RELATIVE as X += B + A + instead of X = B + A this does not work any longer, since ld + clears it. + + The following method relies on the fact that sparcv9 ABI maximal + page length is 1MB and all ELF segments on sparc64 are aligned + to 1MB. Also, it relies on _DYNAMIC coming after _GLOBAL_OFFSET_TABLE_ + and assumes that they both fit into the first 1MB of the RW segment. + This should be true for some time unless ld.so grows too much, at the + moment the whole stripped ld.so is 128KB and only smaller part of that + is in the RW segment. */ + + return ((Elf64_Addr)elf_pic_register - *elf_pic_register + 0xfffff) + & ~0xfffffUL; } /* We have 4 cases to handle. And we code different code sequences |