133 lines
4.1 KiB
C
133 lines
4.1 KiB
C
/* DWARF2 EH unwinding support for S/390 Linux.
|
|
Copyright (C) 2004-2020 Free Software Foundation, Inc.
|
|
|
|
This file is part of GCC.
|
|
|
|
GCC is free software; you can redistribute it and/or modify it under
|
|
the terms of the GNU General Public License as published by the Free
|
|
Software Foundation; either version 3, or (at your option) any later
|
|
version.
|
|
|
|
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
for more details.
|
|
|
|
Under Section 7 of GPL version 3, you are granted additional
|
|
permissions described in the GCC Runtime Library Exception, version
|
|
3.1, as published by the Free Software Foundation.
|
|
|
|
You should have received a copy of the GNU General Public License and
|
|
a copy of the GCC Runtime Library Exception along with this program;
|
|
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* Do code reading to identify a signal frame, and set the frame
|
|
state data appropriately. See unwind-dw2.c for the structs. */
|
|
|
|
#define MD_FALLBACK_FRAME_STATE_FOR s390_fallback_frame_state
|
|
|
|
static _Unwind_Reason_Code
|
|
s390_fallback_frame_state (struct _Unwind_Context *context,
|
|
_Unwind_FrameState *fs)
|
|
{
|
|
static const unsigned char dwarf_to_fpr_map[16] =
|
|
{ 0, 2, 4, 6, 1, 3, 5, 7, 8, 10, 12, 14, 9, 11, 13, 15 };
|
|
unsigned char *pc = context->ra;
|
|
long new_cfa;
|
|
int i;
|
|
|
|
typedef struct
|
|
{
|
|
unsigned long psw_mask;
|
|
unsigned long psw_addr;
|
|
unsigned long gprs[16];
|
|
unsigned int acrs[16];
|
|
unsigned int fpc;
|
|
unsigned int __pad;
|
|
double fprs[16];
|
|
} __attribute__ ((__aligned__ (8))) sigregs_;
|
|
|
|
sigregs_ *regs;
|
|
int *signo;
|
|
|
|
/* svc $__NR_sigreturn or svc $__NR_rt_sigreturn */
|
|
if (pc[0] != 0x0a || (pc[1] != 119 && pc[1] != 173))
|
|
return _URC_END_OF_STACK;
|
|
|
|
/* Legacy frames:
|
|
old signal mask (8 bytes)
|
|
pointer to sigregs (8 bytes) - points always to next location
|
|
sigregs
|
|
retcode
|
|
This frame layout was used on kernels < 2.6.9 for non-RT frames,
|
|
and on kernels < 2.4.13 for RT frames as well. Note that we need
|
|
to look at RA to detect this layout -- this means that if you use
|
|
sa_restorer to install a different signal restorer on a legacy
|
|
kernel, unwinding from signal frames will not work. */
|
|
if (context->ra == context->cfa + 16 + sizeof (sigregs_))
|
|
{
|
|
regs = (sigregs_ *)(context->cfa + 16);
|
|
signo = NULL;
|
|
}
|
|
|
|
/* New-style RT frame:
|
|
retcode + alignment (8 bytes)
|
|
siginfo (128 bytes)
|
|
ucontext (contains sigregs) */
|
|
else if (pc[1] == 173 /* __NR_rt_sigreturn */)
|
|
{
|
|
struct ucontext_
|
|
{
|
|
unsigned long uc_flags;
|
|
struct ucontext_ *uc_link;
|
|
unsigned long uc_stack[3];
|
|
sigregs_ uc_mcontext;
|
|
} *uc = context->cfa + 8 + 128;
|
|
|
|
regs = &uc->uc_mcontext;
|
|
signo = context->cfa + sizeof(long);
|
|
}
|
|
|
|
/* New-style non-RT frame:
|
|
old signal mask (8 bytes)
|
|
pointer to sigregs (followed by signal number) */
|
|
else
|
|
{
|
|
regs = *(sigregs_ **)(context->cfa + 8);
|
|
signo = (int *)(regs + 1);
|
|
}
|
|
|
|
new_cfa = regs->gprs[15] + 16*sizeof(long) + 32;
|
|
fs->regs.cfa_how = CFA_REG_OFFSET;
|
|
fs->regs.cfa_reg = 15;
|
|
fs->regs.cfa_offset =
|
|
new_cfa - (long) context->cfa + 16*sizeof(long) + 32;
|
|
|
|
for (i = 0; i < 16; i++)
|
|
{
|
|
fs->regs.reg[i].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[i].loc.offset =
|
|
(long)®s->gprs[i] - new_cfa;
|
|
}
|
|
for (i = 0; i < 16; i++)
|
|
{
|
|
fs->regs.reg[16+i].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[16+i].loc.offset =
|
|
(long)®s->fprs[dwarf_to_fpr_map[i]] - new_cfa;
|
|
}
|
|
|
|
/* Load return addr from PSW into dummy register 32. */
|
|
|
|
fs->regs.reg[32].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[32].loc.offset = (long)®s->psw_addr - new_cfa;
|
|
fs->retaddr_column = 32;
|
|
/* SIGILL, SIGFPE and SIGTRAP are delivered with psw_addr
|
|
after the faulting instruction rather than before it.
|
|
Don't set FS->signal_frame in that case. */
|
|
if (!signo || (*signo != 4 && *signo != 5 && *signo != 8))
|
|
fs->signal_frame = 1;
|
|
|
|
return _URC_NO_REASON;
|
|
}
|