| Message ID | 1545167083-16764-18-git-send-email-vgupta@synopsys.com |
|---|---|
| State | New |
| Headers | show |
| Series | glibc port to ARC processors | expand |
On Dez 18 2018, Vineet Gupta <vineet.gupta1@synopsys.com> wrote: > diff --git a/sysdeps/unix/sysv/linux/arc/setcontext.S b/sysdeps/unix/sysv/linux/arc/setcontext.S > index 3f503c661d95..6ec2ec0ddc79 100644 > --- a/sysdeps/unix/sysv/linux/arc/setcontext.S > +++ b/sysdeps/unix/sysv/linux/arc/setcontext.S > @@ -79,6 +79,8 @@ weak_alias(__setcontext, setcontext) > > ENTRY(__startcontext) > > + cfi_register (blink, r15) > + You should precede that with a dummy .cfi_label (see sysdeps/riscv/start.S) to force the CFI into the FDE instead of the CIE. Also, can you use cfi_undefined instead? Andreas.
On 12/18/18 2:36 PM, Andreas Schwab wrote: >> ENTRY(__startcontext) >> >> + cfi_register (blink, r15) >> + > You should precede that with a dummy .cfi_label (see > sysdeps/riscv/start.S) to force the CFI into the FDE instead of the > CIE. Also, can you use cfi_undefined instead? Yes that works as well. ENTRY (__startcontext) - cfi_register (blink, r15) + .cfi_label .Ldummy + cfi_undefined (blink) 00035e14 <__startcontext>: 35e14: jl [r13] 35e18: mov r0,r14 35e1c: breq.nt r0,0,8 ;35e24 <__startcontext+0x10> 35e20: bl -168 ;35d78 <setcontext> 35e24: b -38248 ;2c8bc <exit> New ---- 0000058c 00000010 00000590 FDE cie=00000000 pc=00035e14..00035e28 DW_CFA_undefined: r31 DW_CFA_nop Old ---- 00035df4 <__startcontext>: 35df4: jl [r13] 35df8: mov r0,r14 35dfc: breq.nt r0,0,8 ;35e04 <__startcontext+0x10> 35e00: bl -168 ;35d58 <setcontext> 35e04: b -38248 ;2c89c <exit> 0000058c 00000014 00000000 CIE Version: 1 Augmentation: "zR" Code alignment factor: 1 Data alignment factor: -4 Return address column: 31 Augmentation data: 1b DW_CFA_def_cfa: r28 ofs 0 DW_CFA_register: r31 in r15 DW_CFA_nop 000005a4 00000010 0000001c FDE cie=0000058c pc=00035df4..00035e08 DW_CFA_nop DW_CFA_nop DW_CFA_nop
diff --git a/ChangeLog b/ChangeLog index d3a979a9236b..39ff298b0091 100644 --- a/ChangeLog +++ b/ChangeLog @@ -110,6 +110,8 @@ * sysdeps/arc/entry.h: Add ENTRY_POINT define check. * sysdeps/arc/crti.S: add .hidden annotations. * sysdeps/unix/sysv/linux/arc/ipc_priv.h: New file. + * sysdeps/unix/sysv/linux/arc/makecontext.c: clear r15. + * sysdeps/unix/sysv/linux/arc/setcontext.S: set blink from r15. 2018-12-17 Joseph Myers <joseph@codesourcery.com> diff --git a/sysdeps/unix/sysv/linux/arc/makecontext.c b/sysdeps/unix/sysv/linux/arc/makecontext.c index 7018bed9d64a..8d233f83da7e 100644 --- a/sysdeps/unix/sysv/linux/arc/makecontext.c +++ b/sysdeps/unix/sysv/linux/arc/makecontext.c @@ -45,6 +45,7 @@ __makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...) */ ucp->uc_mcontext.callee.r13 = (unsigned long) func; ucp->uc_mcontext.callee.r14 = (unsigned long) ucp->uc_link; + ucp->uc_mcontext.callee.r15 = 0; r = &ucp->uc_mcontext.scratch.r0; diff --git a/sysdeps/unix/sysv/linux/arc/setcontext.S b/sysdeps/unix/sysv/linux/arc/setcontext.S index 3f503c661d95..6ec2ec0ddc79 100644 --- a/sysdeps/unix/sysv/linux/arc/setcontext.S +++ b/sysdeps/unix/sysv/linux/arc/setcontext.S @@ -79,6 +79,8 @@ weak_alias(__setcontext, setcontext) ENTRY(__startcontext) + cfi_register (blink, r15) + /* call user @func, loaded in r13 by setcontext() */ jl [r13]
Terminate the unwinding by telling unwinder to fetch return address (BLINK) from r15 which has been set apriori to 0. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> --- ChangeLog | 2 ++ sysdeps/unix/sysv/linux/arc/makecontext.c | 1 + sysdeps/unix/sysv/linux/arc/setcontext.S | 2 ++ 3 files changed, 5 insertions(+)