--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/config/rs6000/linux-unwind.h	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,358 @@
+/* DWARF2 EH unwinding support for PowerPC and PowerPC64 Linux.
+   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 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/>.  */
+
+#define R_LR		65
+#define R_CR2		70
+#define R_VR0		77
+#define R_VRSAVE	109
+#define R_VSCR		110
+
+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 (*(const unsigned int *) (pc + 4) != 0x44000002)
+    return NULL;
+  if (*(const unsigned int *) (pc + 0) == 0x38007777
+      || *(const 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 (*(const unsigned int *) (pc + 0) == 0x38006666
+	   || *(const 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->regs.cfa_how = CFA_REG_OFFSET;
+  fs->regs.cfa_reg = STACK_POINTER_REGNUM;
+  fs->regs.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) &regs->gpr[i] - new_cfa;
+      }
+
+  fs->regs.reg[R_CR2].how = REG_SAVED_OFFSET;
+  /* CR? regs are always 32-bit and PPC is big-endian, so in 64-bit
+     libgcc loc.offset needs to point to the low 32 bits of regs->ccr.  */
+  fs->regs.reg[R_CR2].loc.offset = (long) &regs->ccr - new_cfa
+				   + sizeof (long) - 4;
+
+  fs->regs.reg[R_LR].how = REG_SAVED_OFFSET;
+  fs->regs.reg[R_LR].loc.offset = (long) &regs->link - new_cfa;
+
+  fs->regs.reg[ARG_POINTER_REGNUM].how = REG_SAVED_OFFSET;
+  fs->regs.reg[ARG_POINTER_REGNUM].loc.offset = (long) &regs->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) &regs->fpr[i] - new_cfa;
+      }
+
+  /* If we have a VMX unit...  */
+  if (hwcap & 0x10000000)
+    {
+      struct gcc_vregs *vregs;
+#ifdef __powerpc64__
+      vregs = regs->vp;
+#else
+      vregs = &regs->vregs;
+#endif
+      if (regs->msr & (1 << 25))
+	{
+	  for (i = 0; i < 32; i++)
+	    {
+	      fs->regs.reg[i + R_VR0].how = REG_SAVED_OFFSET;
+	      fs->regs.reg[i + R_VR0].loc.offset
+		= (long) &vregs->vr[i] - new_cfa;
+	    }
+
+	  fs->regs.reg[R_VSCR].how = REG_SAVED_OFFSET;
+	  fs->regs.reg[R_VSCR].loc.offset = (long) &vregs->vscr - new_cfa;
+	}
+
+      fs->regs.reg[R_VRSAVE].how = REG_SAVED_OFFSET;
+      fs->regs.reg[R_VRSAVE].loc.offset = (long) &vregs->vsave - new_cfa;
+    }
+
+  /* If we have SPE register high-parts... we check at compile-time to
+     avoid expanding the code for all other PowerPC.  */
+#ifdef __SPE__
+  for (i = 0; i < 32; i++)
+    {
+      fs->regs.reg[i + FIRST_PSEUDO_REGISTER - 1].how = REG_SAVED_OFFSET;
+      fs->regs.reg[i + FIRST_PSEUDO_REGISTER - 1].loc.offset
+	= (long) &regs->vregs - new_cfa + 4 * i;
+    }
+#endif
+
+  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, R_LR);
+      if (insn && *insn == 0xE8410028)
+	_Unwind_SetGRPtr (context, 2, context->cfa + 40);
+    }
+#endif
+}