diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/alpha/rt_sigaction.S | 54 |
2 files changed, 30 insertions, 29 deletions
@@ -1,3 +1,8 @@ +2004-01-15 Richard Henderson <rth@redhat.com> + + * sysdeps/unix/sysv/linux/alpha/rt_sigaction.S: Prefix stubs with + __syscall_, move nop inside, adjust users by +4. + 2004-01-14 Steven Munroe <sjmunroe@us.ibm.com> * include/libc-symbols.h [HAVE_ASM_GLOBAL_DOT_NAME] diff --git a/sysdeps/unix/sysv/linux/alpha/rt_sigaction.S b/sysdeps/unix/sysv/linux/alpha/rt_sigaction.S index aad988b..e27949f 100644 --- a/sysdeps/unix/sysv/linux/alpha/rt_sigaction.S +++ b/sysdeps/unix/sysv/linux/alpha/rt_sigaction.S @@ -26,7 +26,6 @@ This just about halves signal delivery time. */ -#ifdef __NR_rt_sigaction .text ENTRY(__syscall_rt_sigaction) @@ -42,12 +41,20 @@ ENTRY(__syscall_rt_sigaction) beq a1, 0f ldl t0, 8(a1) # sa_flags - ldah a4, sigreturn(gp) !gprelhigh - ldah t1, rt_sigreturn(gp) !gprelhigh - lda a4, sigreturn(a4) !gprellow - lda t1, rt_sigreturn(t1) !gprellow - and t0, 0x00000040, t0 # SA_SIGINFO + + /* The unwinder will subtract one from the return address when + attempting to find the call instruction that led us here. + Since we didn't get here via a normal call, if we do nothing + we would pick up the wrong symbol and the wrong FDE. Account + for this by adding a nop to the start of the function and + then skipping it here by adding 4. */ + ldah a4, __syscall_sigreturn+4(gp) !gprelhigh + ldah t1, __syscall_rt_sigreturn+4(gp) !gprelhigh + lda a4, __syscall_sigreturn+4(a4) !gprellow + lda t1, __syscall_rt_sigreturn+4(t1) !gprellow + and t0, 0x40, t0 # SA_SIGINFO cmovne t0, t1, a4 + 0: ldi v0, __NR_rt_sigaction callsys bne a3, SYSCALL_ERROR_LABEL @@ -57,10 +64,10 @@ PSEUDO_END(__syscall_rt_sigaction) /* To enable unwinding through the signal frame without special hackery elsewhere, describe the entire struct sigcontext with unwind info. - Note that we begin the unwind info one instruction before the start - of the function; the unwinder will subtract one from the return address - attempting to find the call instruction that led us here, since we - didn't get here via a normal call. */ + + In order to minimize the size of the encoding, we set the CFA to the + end of the sigcontext, which makes all of the registers have small + negative offsets from that. */ .macro SIGCONTEXT_REGS_I base, from=0 cfi_offset (\from, \base + (4 + \from) * 8) @@ -91,34 +98,23 @@ PSEUDO_END(__syscall_rt_sigaction) cfi_startproc cfi_return_column (64) SIGCONTEXT_REGS -648 + cfi_def_cfa_offset (648) +__syscall_sigreturn: nop -sigreturn: mov sp, a0 ldi v0, __NR_sigreturn callsys - cfi_endproc - .size sigreturn, .-sigreturn - .type sigreturn, @function + .size __syscall_sigreturn, .-__syscall_sigreturn + .type __syscall_sigreturn, @function - cfi_startproc - cfi_return_column (64) - SIGCONTEXT_REGS -648 cfi_def_cfa_offset (176 + 648) +__syscall_rt_sigreturn: nop -rt_sigreturn: mov sp,a0 ldi v0,__NR_rt_sigreturn callsys - cfi_endproc - .size rt_sigreturn, .-rt_sigreturn - .type rt_sigreturn, @function + .size __syscall_rt_sigreturn, .-__syscall_rt_sigreturn + .type __syscall_rt_sigreturn, @function -#else -ENTRY(__syscall_rt_sigaction) - ldgp $29,0($27) - .prologue 1 - ldi $0,ENOSYS - SYSCALL_ERROR_HANDLER -END(__syscall_rt_sigaction) -#endif + cfi_endproc |