349 lines
10 KiB
C
349 lines
10 KiB
C
/* DWARF2 EH unwinding support for PowerPC and PowerPC64 Linux.
|
|
Copyright (C) 2004, 2005, 2006 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 2, or (at your
|
|
option) any later version.
|
|
|
|
In addition to the permissions in the GNU General Public License,
|
|
the Free Software Foundation gives you unlimited permission to link
|
|
the compiled version of this file with other programs, and to
|
|
distribute those programs without any restriction coming from the
|
|
use of this file. (The General Public License restrictions do
|
|
apply in other respects; for example, they cover modification of
|
|
the file, and distribution when not linked into another program.)
|
|
|
|
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.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GCC; see the file COPYING. If not, write to the
|
|
Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
|
|
MA 02110-1301, USA. */
|
|
|
|
/* This file defines our own versions of various kernel and user
|
|
structs, so that system headers are not needed, which otherwise
|
|
can make bootstrapping a new toolchain difficult. Do not use
|
|
these structs elsewhere; Many fields are missing, particularly
|
|
from the end of the structures. */
|
|
|
|
struct gcc_vregs
|
|
{
|
|
__attribute__ ((vector_size (16))) int vr[32];
|
|
#ifdef __powerpc64__
|
|
unsigned int pad1[3];
|
|
unsigned int vscr;
|
|
unsigned int vsave;
|
|
unsigned int pad2[3];
|
|
#else
|
|
unsigned int vsave;
|
|
unsigned int pad[2];
|
|
unsigned int vscr;
|
|
#endif
|
|
};
|
|
|
|
struct gcc_regs
|
|
{
|
|
unsigned long gpr[32];
|
|
unsigned long nip;
|
|
unsigned long msr;
|
|
unsigned long orig_gpr3;
|
|
unsigned long ctr;
|
|
unsigned long link;
|
|
unsigned long xer;
|
|
unsigned long ccr;
|
|
unsigned long softe;
|
|
unsigned long trap;
|
|
unsigned long dar;
|
|
unsigned long dsisr;
|
|
unsigned long result;
|
|
unsigned long pad1[4];
|
|
double fpr[32];
|
|
unsigned int pad2;
|
|
unsigned int fpscr;
|
|
#ifdef __powerpc64__
|
|
struct gcc_vregs *vp;
|
|
#else
|
|
unsigned int pad3[2];
|
|
#endif
|
|
struct gcc_vregs vregs;
|
|
};
|
|
|
|
struct gcc_ucontext
|
|
{
|
|
#ifdef __powerpc64__
|
|
unsigned long pad[28];
|
|
#else
|
|
unsigned long pad[12];
|
|
#endif
|
|
struct gcc_regs *regs;
|
|
struct gcc_regs rsave;
|
|
};
|
|
|
|
#ifdef __powerpc64__
|
|
|
|
enum { SIGNAL_FRAMESIZE = 128 };
|
|
|
|
/* If PC is at a sigreturn trampoline, return a pointer to the
|
|
regs. Otherwise return NULL. */
|
|
|
|
static struct gcc_regs *
|
|
get_regs (struct _Unwind_Context *context)
|
|
{
|
|
const unsigned char *pc = context->ra;
|
|
|
|
/* addi r1, r1, 128; li r0, 0x0077; sc (sigreturn) */
|
|
/* addi r1, r1, 128; li r0, 0x00AC; sc (rt_sigreturn) */
|
|
if (*(unsigned int *) (pc + 0) != 0x38210000 + SIGNAL_FRAMESIZE
|
|
|| *(unsigned int *) (pc + 8) != 0x44000002)
|
|
return NULL;
|
|
if (*(unsigned int *) (pc + 4) == 0x38000077)
|
|
{
|
|
struct sigframe {
|
|
char gap[SIGNAL_FRAMESIZE];
|
|
unsigned long pad[7];
|
|
struct gcc_regs *regs;
|
|
} *frame = (struct sigframe *) context->cfa;
|
|
return frame->regs;
|
|
}
|
|
else if (*(unsigned int *) (pc + 4) == 0x380000AC)
|
|
{
|
|
/* This works for 2.4 kernels, but not for 2.6 kernels with vdso
|
|
because pc isn't pointing into the stack. Can be removed when
|
|
no one is running 2.4.19 or 2.4.20, the first two ppc64
|
|
kernels released. */
|
|
struct rt_sigframe_24 {
|
|
int tramp[6];
|
|
void *pinfo;
|
|
struct gcc_ucontext *puc;
|
|
} *frame24 = (struct rt_sigframe_24 *) pc;
|
|
|
|
/* Test for magic value in *puc of vdso. */
|
|
if ((long) frame24->puc != -21 * 8)
|
|
return frame24->puc->regs;
|
|
else
|
|
{
|
|
/* This works for 2.4.21 and later kernels. */
|
|
struct rt_sigframe {
|
|
char gap[SIGNAL_FRAMESIZE];
|
|
struct gcc_ucontext uc;
|
|
unsigned long pad[2];
|
|
int tramp[6];
|
|
void *pinfo;
|
|
struct gcc_ucontext *puc;
|
|
} *frame = (struct rt_sigframe *) context->cfa;
|
|
return frame->uc.regs;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
#else /* !__powerpc64__ */
|
|
|
|
enum { SIGNAL_FRAMESIZE = 64 };
|
|
|
|
static struct gcc_regs *
|
|
get_regs (struct _Unwind_Context *context)
|
|
{
|
|
const unsigned char *pc = context->ra;
|
|
|
|
/* li r0, 0x7777; sc (sigreturn old) */
|
|
/* li r0, 0x0077; sc (sigreturn new) */
|
|
/* li r0, 0x6666; sc (rt_sigreturn old) */
|
|
/* li r0, 0x00AC; sc (rt_sigreturn new) */
|
|
if (*(unsigned int *) (pc + 4) != 0x44000002)
|
|
return NULL;
|
|
if (*(unsigned int *) (pc + 0) == 0x38007777
|
|
|| *(unsigned int *) (pc + 0) == 0x38000077)
|
|
{
|
|
struct sigframe {
|
|
char gap[SIGNAL_FRAMESIZE];
|
|
unsigned long pad[7];
|
|
struct gcc_regs *regs;
|
|
} *frame = (struct sigframe *) context->cfa;
|
|
return frame->regs;
|
|
}
|
|
else if (*(unsigned int *) (pc + 0) == 0x38006666
|
|
|| *(unsigned int *) (pc + 0) == 0x380000AC)
|
|
{
|
|
struct rt_sigframe {
|
|
char gap[SIGNAL_FRAMESIZE + 16];
|
|
char siginfo[128];
|
|
struct gcc_ucontext uc;
|
|
} *frame = (struct rt_sigframe *) context->cfa;
|
|
return frame->uc.regs;
|
|
}
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
/* Find an entry in the process auxiliary vector. The canonical way to
|
|
test for VMX is to look at AT_HWCAP. */
|
|
|
|
static long
|
|
ppc_linux_aux_vector (long which)
|
|
{
|
|
/* __libc_stack_end holds the original stack passed to a process. */
|
|
extern long *__libc_stack_end;
|
|
long argc;
|
|
char **argv;
|
|
char **envp;
|
|
struct auxv
|
|
{
|
|
long a_type;
|
|
long a_val;
|
|
} *auxp;
|
|
|
|
/* The Linux kernel puts argc first on the stack. */
|
|
argc = __libc_stack_end[0];
|
|
/* Followed by argv, NULL terminated. */
|
|
argv = (char **) __libc_stack_end + 1;
|
|
/* Followed by environment string pointers, NULL terminated. */
|
|
envp = argv + argc + 1;
|
|
while (*envp++)
|
|
continue;
|
|
/* Followed by the aux vector, zero terminated. */
|
|
for (auxp = (struct auxv *) envp; auxp->a_type != 0; ++auxp)
|
|
if (auxp->a_type == which)
|
|
return auxp->a_val;
|
|
return 0;
|
|
}
|
|
|
|
/* 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 ppc_fallback_frame_state
|
|
|
|
static _Unwind_Reason_Code
|
|
ppc_fallback_frame_state (struct _Unwind_Context *context,
|
|
_Unwind_FrameState *fs)
|
|
{
|
|
static long hwcap = 0;
|
|
struct gcc_regs *regs = get_regs (context);
|
|
long new_cfa;
|
|
int i;
|
|
|
|
if (regs == NULL)
|
|
return _URC_END_OF_STACK;
|
|
|
|
new_cfa = regs->gpr[STACK_POINTER_REGNUM];
|
|
fs->cfa_how = CFA_REG_OFFSET;
|
|
fs->cfa_reg = STACK_POINTER_REGNUM;
|
|
fs->cfa_offset = new_cfa - (long) context->cfa;
|
|
|
|
for (i = 0; i < 32; i++)
|
|
if (i != STACK_POINTER_REGNUM)
|
|
{
|
|
fs->regs.reg[i].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[i].loc.offset = (long) ®s->gpr[i] - new_cfa;
|
|
}
|
|
|
|
fs->regs.reg[CR2_REGNO].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[CR2_REGNO].loc.offset = (long) ®s->ccr - new_cfa;
|
|
|
|
fs->regs.reg[LINK_REGISTER_REGNUM].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[LINK_REGISTER_REGNUM].loc.offset = (long) ®s->link - new_cfa;
|
|
|
|
fs->regs.reg[ARG_POINTER_REGNUM].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[ARG_POINTER_REGNUM].loc.offset = (long) ®s->nip - new_cfa;
|
|
fs->retaddr_column = ARG_POINTER_REGNUM;
|
|
fs->signal_frame = 1;
|
|
|
|
if (hwcap == 0)
|
|
{
|
|
hwcap = ppc_linux_aux_vector (16);
|
|
/* These will already be set if we found AT_HWCAP. A nonzero
|
|
value stops us looking again if for some reason we couldn't
|
|
find AT_HWCAP. */
|
|
#ifdef __powerpc64__
|
|
hwcap |= 0xc0000000;
|
|
#else
|
|
hwcap |= 0x80000000;
|
|
#endif
|
|
}
|
|
|
|
/* If we have a FPU... */
|
|
if (hwcap & 0x08000000)
|
|
for (i = 0; i < 32; i++)
|
|
{
|
|
fs->regs.reg[i + 32].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[i + 32].loc.offset = (long) ®s->fpr[i] - new_cfa;
|
|
}
|
|
|
|
/* If we have a VMX unit... */
|
|
if (hwcap & 0x10000000)
|
|
{
|
|
struct gcc_vregs *vregs;
|
|
#ifdef __powerpc64__
|
|
vregs = regs->vp;
|
|
#else
|
|
vregs = ®s->vregs;
|
|
#endif
|
|
if (regs->msr & (1 << 25))
|
|
{
|
|
for (i = 0; i < 32; i++)
|
|
{
|
|
fs->regs.reg[i + FIRST_ALTIVEC_REGNO].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[i + FIRST_ALTIVEC_REGNO].loc.offset
|
|
= (long) &vregs[i] - new_cfa;
|
|
}
|
|
|
|
fs->regs.reg[VSCR_REGNO].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[VSCR_REGNO].loc.offset = (long) &vregs->vscr - new_cfa;
|
|
}
|
|
|
|
fs->regs.reg[VRSAVE_REGNO].how = REG_SAVED_OFFSET;
|
|
fs->regs.reg[VRSAVE_REGNO].loc.offset = (long) &vregs->vsave - new_cfa;
|
|
}
|
|
|
|
return _URC_NO_REASON;
|
|
}
|
|
|
|
#define MD_FROB_UPDATE_CONTEXT frob_update_context
|
|
|
|
static void
|
|
frob_update_context (struct _Unwind_Context *context, _Unwind_FrameState *fs ATTRIBUTE_UNUSED)
|
|
{
|
|
const unsigned int *pc = (const unsigned int *) context->ra;
|
|
|
|
/* Fix up for 2.6.12 - 2.6.16 Linux kernels that have vDSO, but don't
|
|
have S flag in it. */
|
|
#ifdef __powerpc64__
|
|
/* addi r1, r1, 128; li r0, 0x0077; sc (sigreturn) */
|
|
/* addi r1, r1, 128; li r0, 0x00AC; sc (rt_sigreturn) */
|
|
if (pc[0] == 0x38210000 + SIGNAL_FRAMESIZE
|
|
&& (pc[1] == 0x38000077 || pc[1] == 0x380000AC)
|
|
&& pc[2] == 0x44000002)
|
|
_Unwind_SetSignalFrame (context, 1);
|
|
#else
|
|
/* li r0, 0x7777; sc (sigreturn old) */
|
|
/* li r0, 0x0077; sc (sigreturn new) */
|
|
/* li r0, 0x6666; sc (rt_sigreturn old) */
|
|
/* li r0, 0x00AC; sc (rt_sigreturn new) */
|
|
if ((pc[0] == 0x38007777 || pc[0] == 0x38000077
|
|
|| pc[0] == 0x38006666 || pc[0] == 0x380000AC)
|
|
&& pc[1] == 0x44000002)
|
|
_Unwind_SetSignalFrame (context, 1);
|
|
#endif
|
|
|
|
#ifdef __powerpc64__
|
|
if (fs->regs.reg[2].how == REG_UNSAVED)
|
|
{
|
|
/* If the current unwind info (FS) does not contain explicit info
|
|
saving R2, then we have to do a minor amount of code reading to
|
|
figure out if it was saved. The big problem here is that the
|
|
code that does the save/restore is generated by the linker, so
|
|
we have no good way to determine at compile time what to do. */
|
|
unsigned int *insn
|
|
= (unsigned int *) _Unwind_GetGR (context, LINK_REGISTER_REGNUM);
|
|
if (*insn == 0xE8410028)
|
|
_Unwind_SetGRPtr (context, 2, context->cfa + 40);
|
|
}
|
|
#endif
|
|
}
|