diff options
Diffstat (limited to 'sysdeps/alpha/dl-machine.h')
-rw-r--r-- | sysdeps/alpha/dl-machine.h | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/sysdeps/alpha/dl-machine.h b/sysdeps/alpha/dl-machine.h index 7a51df5..49d6830 100644 --- a/sysdeps/alpha/dl-machine.h +++ b/sysdeps/alpha/dl-machine.h @@ -86,7 +86,7 @@ elf_machine_load_address (void) /* Set up the loaded object described by L so its unrelocated PLT entries will jump to the on-demand fixup code in dl-runtime.c. */ -static inline void +static inline int elf_machine_runtime_setup (struct link_map *l, int lazy) { Elf64_Addr plt; @@ -104,7 +104,13 @@ elf_machine_runtime_setup (struct link_map *l, int lazy) /* Identify this shared object */ *(Elf64_Addr *)(plt + 24) = (Elf64_Addr) l; + + /* If the first instruction of the plt entry is not + "br $28, plt0", we cannot do lazy relocation. */ + lazy = (*(unsigned *)(plt + 32) == 0xc39ffff7); } + + return lazy; } /* This code is used in dl-runtime.c to call the `fixup' function @@ -145,9 +151,11 @@ _dl_runtime_resolve: .prologue 1 /* Set up the arguments for _dl_runtime_resolve. */ /* $16 = link_map out of plt0 */ + /* $17 = offset of reloc entry = ($28 - $27 - 20) /12 * 24 */ + subq $28, $27, $17 ldq $16, 8($27) - /* $17 = offset of reloc entry */ - mov $28, $17 + subq $17, 20, $17 + addq $17, $17, $17 /* Do the fixup */ bsr $26, fixup..ng /* Move the destination address into position. */ @@ -290,14 +298,18 @@ elf_alpha_fix_plt(struct link_map *l, lo = (short)hi; hi = (hi - lo) >> 16; - /* Emit "ldah $27,H($27)" */ - plte[0] = 0x277b0000 | (hi & 0xffff); - /* Emit "lda $27,L($27)" */ plte[1] = 0x237b0000 | (lo & 0xffff); /* Emit "br $31,function" */ plte[2] = 0xc3e00000 | (edisp & 0x1fffff); + + /* Think about thread-safety -- the previous instructions must be + committed to memory before the first is overwritten. */ + __asm__ __volatile__("wmb" : : : "memory"); + + /* Emit "ldah $27,H($27)" */ + plte[0] = 0x277b0000 | (hi & 0xffff); } else { @@ -310,14 +322,18 @@ elf_alpha_fix_plt(struct link_map *l, lo = (short)hi; hi = (hi - lo) >> 16; - /* Emit "ldah $27,H($27)" */ - plte[0] = 0x277b0000 | (hi & 0xffff); - /* Emit "ldq $27,L($27)" */ plte[1] = 0xa77b0000 | (lo & 0xffff); /* Emit "jmp $31,($27)" */ plte[2] = 0x6bfb0000; + + /* Think about thread-safety -- the previous instructions must be + committed to memory before the first is overwritten. */ + __asm__ __volatile__("wmb" : : : "memory"); + + /* Emit "ldah $27,H($27)" */ + plte[0] = 0x277b0000 | (hi & 0xffff); } /* At this point, if we've been doing runtime resolution, Icache is dirty. |