tm.texi (MD_UNWIND_SUPPORT): Document.

	* doc/tm.texi (MD_UNWIND_SUPPORT): Document.
	(MD_FALLBACK_FRAME_STATE_FOR): Update.
	* unwind-dw2.c (MD_UNWIND_SUPPORT): #include if defined.
	(uw_frame_state_for): Adjust MD_FALLBACK_FRAME_STATE_FOR invocation.
	(MD_FROB_UPDATE_CONTEXT): Remove default.
	(uw_update_context_1): Instead #ifdef invocation.
	* config/ia64/unwind-ia64.c (MD_UNWIND_SUPPORT): #include if defined.
	(uw_frame_state_for): Adjust MD_FALLBACK_FRAME_STATE_FOR invocation.
	* config/alpha/gnu.h (MD_FALLBACK_FRAME_STATE_FOR): Don't undef.
	(MD_UNWIND_SUPPORT): Undefine this instead.
	* config/i386/gnu.h: Likewise.
	* config/alpha/linux-unwind.h: New file, macro converted to
	function, extracted from..
	* config/alpha/linux.h (MD_FALLBACK_FRAME_STATE_FOR): ..this.
	(MD_UNWIND_SUPPORT): Define.
	* config/alpha/vms-unwind.h, config/alpha/vms.h: Likewise.
	* config/i386/linux-unwind.h, config/i386/linux.h,
	config/i386/linux64.h: Likewise.
	* config/ia64/linux-unwind.h, config/ia64/linux.h: Likewise.
	MD_HANDLE_UNWABI too.
	* config/mips/linux-unwind.h, config/mips/linux.h: Likewise.
	* config/pa/linux-unwind.h, config/pa/pa32-linux.h: Likewise.
	* config/rs6000/darwin-unwind.h, config/rs6000/darwin.h: Likewise.
	* config/s390/linux-unwind.h, config/s390/linux.h: Likewise.
	* config/sparc/linux-unwind.h, config/sparc/linux.h,
	config/sparc/linux64.h: Likewise.
	* config/sh/linux-unwind.h, config/sh/linux.h: Likewise, but merge
	SH_FALLBACK_FRAME_FLOAT_STATE into sh_fallback_frame_state.
	* config/rs6000/linux-unwind.h, config/rs6000/linux.h,
	config/rs6000/linux64.h: Likewise.  Split out get_sigcontext
	function.  Use ARG_POINTER_REGNUM for 32-bit temp reg too.

From-SVN: r87167

1 files changed, 131 insertions, 0 deletions

diff --git a/gcc/config/s390/linux-unwind.h b/gcc/config/s390/linux-unwind.h
new file mode 100644
index 00000000000..3713f1821a9
--- /dev/null
+++ b/gcc/config/s390/linux-unwind.h
@@ -0,0 +1,131 @@
+/* DWARF2 EH unwinding support for S/390 Linux.
+   Copyright (C) 2004 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.
+
+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, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA.  */
+
+/* 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)
+{
+  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 = NULL;
+
+  /* svc $__NR_sigreturn or svc $__NR_rt_sigreturn  */
+  if (pc[0] != 0x0a || (pc[1] != 119 && pc[1] != 173))
+    return _URC_END_OF_STACK;
+
+  /* New-style RT frame:
+     retcode + alignment (8 bytes)
+     siginfo (128 bytes)
+     ucontext (contains sigregs)  */
+  if (context->ra == context->cfa)
+    {
+      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);
+    }
+
+  /* Old-style RT frame and all non-RT frames:
+     old signal mask (8 bytes)
+     pointer to sigregs  */
+  else
+    {
+      regs = *(sigregs_ **)(context->cfa + 8);
+
+      /* Recent kernels store the signal number immediately after
+	 the sigregs; old kernels have the return trampoline at
+	 this location.  */
+      if ((void *)(regs + 1) != context->ra)
+	signo = (int *)(regs + 1);
+    }
+
+  new_cfa = regs->gprs[15] + 16*sizeof(long) + 32;
+  fs->cfa_how = CFA_REG_OFFSET;
+  fs->cfa_reg = 15;
+  fs->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)&regs->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)&regs->fprs[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)&regs->psw_addr - new_cfa;
+  fs->retaddr_column = 32;
+
+  /* If we got a SIGSEGV or a SIGBUS, the PSW address points *to*
+     the faulting instruction, not after it.  This causes the logic
+     in unwind-dw2.c that decrements the RA to determine the correct
+     CFI region to get confused.  To fix that, we *increment* the RA
+     here in that case.  Note that we cannot modify the RA in place,
+     and the frame state wants a *pointer*, not a value; thus we put
+     the modified RA value into the unused register 33 slot of FS and
+     have the register 32 save address point to that slot.
+
+     Unfortunately, for regular signals on old kernels, we don't know
+     the signal number.  We default to not fiddling with the RA;
+     that can fail in rare cases.  Upgrade your kernel.  */
+
+  if (signo && (*signo == 11 || *signo == 7))
+    {
+      fs->regs.reg[33].loc.exp =
+	(unsigned char *)regs->psw_addr + 1;
+      fs->regs.reg[32].loc.offset =
+	(long)&fs->regs.reg[33].loc.exp - new_cfa;
+    }
+
+  return _URC_NO_REASON;
+}