diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 31e9c5cc848392b7f7ab545c616ee1208fd82e2f..46f33600eef12bdcbc14d78cda7fb45b8346ac50 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,41 @@
+2004-06-28  Geoffrey Keating  <geoffk@apple.com>
+	    Andreas Tobler  <a.tobler@schweiz.ch>
+
+	PR 15813
+	* dwarf2out.c (reg_save): Output DW_CFA_same_value when a
+	register is saved in itself.
+	(initial_return_save): If the return address is a register,
+	it's already there, don't bother to mention it in the CFI.
+	(struct queued_reg_save): Add field saved_reg.
+	(struct reg_saved_in_data): New.
+	(regs_saved_in_regs): New.
+	(num_regs_saved_in_regs): New.
+	(queue_reg_save): Add extra parameter to specify register saved
+	in register.  Remove duplicate entries from queue.  Add comment
+	for function.
+	(flush_queued_reg_saves): Handle registers saved in registers.
+	Update regs_saved_in_regs.  Add comment for function.
+	(clobbers_queued_reg_save): Add comment for function.  Allow
+	for regs_saved_in_regs.
+	(reg_saved_in): New.
+	(dwarf2out_frame_debug_expr): Handle saving registers in other
+	registers.
+	(dwarf2out_frame_debug): Reset regs_saved_in_regs.
+	* unwind-dw2.c (execute_cfa_program): Correct handling of
+	DW_CFA_same_value.  Add FIXME comment about incorrect implementation
+	of DW_CFA_restore_extended.
+	* config/rs6000/rs6000.c (rs6000_emit_prologue): Let
+	dwarf2out_frame_debug_expr see instructions that save registers
+	in other registers or save those other registers in memory.
+
+	* unwind-dw2.c (DWARF_FRAME_REGISTERS): Move to unwind-dw2.h.
+	(_Unwind_FrameState): Likewise.
+	* unwind-dw2.h: New.
+	* Makefile.in (LIB2ADDEHDEP): Add unwind-dw2.h.
+	* config/rs6000/darwin-fallback.c: New file.
+	* config/rs6000/darwin.h (MD_FALLBACK_FRAME_STATE_FOR): Define.
+	* config/rs6000/t-darwin (LIB2FUNCS_EXTRA): Add darwin-fallback.o.
+
 2004-07-01  Alan Modra  <amodra@bigpond.net.au>
 
 	* config/rs6000/rs6000.c (rs6000_mixed_function_arg): Rewrite.
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index aebfc5fd7b4b9f42b2b3c8f0d3f2b5e222c85023..41e84117857cdc4fe07bcb62c0acec50de0a6c74 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -528,7 +528,7 @@ CRTSTUFF_CFLAGS = -O2 $(GCC_CFLAGS) $(INCLUDES) $(MULTILIB_CFLAGS) -g0 \
 # Additional sources to handle exceptions; overridden by targets as needed.
 LIB2ADDEH = $(srcdir)/unwind-dw2.c $(srcdir)/unwind-dw2-fde.c \
    $(srcdir)/unwind-sjlj.c $(srcdir)/gthr-gnat.c $(srcdir)/unwind-c.c
-LIB2ADDEHDEP = unwind.inc unwind-dw2-fde.h
+LIB2ADDEHDEP = unwind.inc unwind-dw2-fde.h unwind-dw2.h
 
 # nm flags to list global symbols in libgcc object files.
 SHLIB_NM_FLAGS = -pg
diff --git a/gcc/config/rs6000/darwin-fallback.c b/gcc/config/rs6000/darwin-fallback.c
new file mode 100644
index 0000000000000000000000000000000000000000..f7756fbac843a845d8a82e72e087abd5316b1e22
--- /dev/null
+++ b/gcc/config/rs6000/darwin-fallback.c
@@ -0,0 +1,432 @@
+/* Fallback frame-state unwinder for Darwin.
+   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.
+
+   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 into combinations with other programs,
+   and to distribute those combinations 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 a combined
+   executable.)
+
+   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.  */
+
+#include "tconfig.h"
+#include "tsystem.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "dwarf2.h"
+#include "unwind.h"
+#include "unwind-dw2.h"
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <ucontext.h>
+
+typedef unsigned long reg_unit;
+
+/* Place in GPRS the parameters to the first 'sc' instruction that would
+   have been executed if we were returning from this CONTEXT, or
+   return false if an unexpected instruction is encountered.  */
+
+static bool
+interpret_libc (reg_unit gprs[32], struct _Unwind_Context *context)
+{
+  uint32_t *pc = (uint32_t *)_Unwind_GetIP (context);
+  uint32_t cr;
+  reg_unit lr = (reg_unit) pc;
+  reg_unit ctr = 0;
+  uint32_t *invalid_address = NULL;
+
+  int i;
+
+  for (i = 0; i < 13; i++)
+    gprs[i] = 1;
+  gprs[1] = _Unwind_GetCFA (context);
+  for (; i < 32; i++)
+    gprs[i] = _Unwind_GetGR (context, i);
+  cr = _Unwind_GetGR (context, CR2_REGNO);
+
+  /* For each supported Libc, we have to track the code flow
+     all the way back into the kernel.
+  
+     This code is believed to support all released Libc/Libsystem builds since
+     Jaguar 6C115, including all the security updates.  To be precise,
+
+     Libc	Libsystem	Build(s)
+     262~1	60~37		6C115
+     262~1	60.2~4		6D52
+     262~1	61~3		6F21-6F22
+     262~1	63~24		6G30-6G37
+     262~1	63~32		6I34-6I35
+     262~1	63~64		6L29-6L60
+     262.4.1~1	63~84		6L123-6R172
+     
+     320~1	71~101		7B85-7D28
+     320~1	71~266		7F54-7F56
+     320~1	71~288		7F112
+     320~1	71~289		7F113
+     320.1.3~1	71.1.1~29	7H60-7H105
+     320.1.3~1	71.1.1~30	7H110-7H113
+     320.1.3~1	71.1.1~31	7H114
+     
+     That's a big table!  It would be insane to try to keep track of
+     every little detail, so we just read the code itself and do what
+     it would do.
+  */
+
+  for (;;)
+    {
+      uint32_t ins = *pc++;
+      
+      if ((ins & 0xFC000003) == 0x48000000)  /* b instruction */
+	{
+	  pc += ((((int32_t) ins & 0x3FFFFFC) ^ 0x2000000) - 0x2000004) / 4;
+	  continue;
+	}
+      if ((ins & 0xFC600000) == 0x2C000000)  /* cmpwi */
+	{
+	  int32_t val1 = (int16_t) ins;
+	  int32_t val2 = gprs[ins >> 16 & 0x1F];
+	  /* Only beq and bne instructions are supported, so we only
+	     need to set the EQ bit.  */
+	  uint32_t mask = 0xF << ((ins >> 21 & 0x1C) ^ 0x1C);
+	  if (val1 == val2)
+	    cr |= mask;
+	  else
+	    cr &= ~mask;
+	  continue;
+	}
+      if ((ins & 0xFEC38003) == 0x40820000)  /* forwards beq/bne */
+	{
+	  if ((cr >> ((ins >> 16 & 0x1F) ^ 0x1F) & 1) == (ins >> 24 & 1))
+	    pc += (ins & 0x7FFC) / 4 - 1;
+	  continue;
+	}
+      if ((ins & 0xFC0007FF) == 0x7C000378) /* or, including mr */
+	{
+	  gprs [ins >> 16 & 0x1F] = (gprs [ins >> 11 & 0x1F] 
+				     | gprs [ins >> 21 & 0x1F]);
+	  continue;
+	}
+      if (ins >> 26 == 0x0E)  /* addi, including li */
+	{
+	  reg_unit src = (ins >> 16 & 0x1F) == 0 ? 0 : gprs [ins >> 16 & 0x1F];
+	  gprs [ins >> 21 & 0x1F] = src + (int16_t) ins;
+	  continue;
+	}
+      if (ins >> 26 == 0x0F)  /* addis, including lis */
+	{
+	  reg_unit src = (ins >> 16 & 0x1F) == 0 ? 0 : gprs [ins >> 16 & 0x1F];
+	  gprs [ins >> 21 & 0x1F] = src + ((int16_t) ins << 16);
+	  continue;
+	}
+      if (ins >> 26 == 0x20)  /* lwz */
+	{
+	  reg_unit src = (ins >> 16 & 0x1F) == 0 ? 0 : gprs [ins >> 16 & 0x1F];
+	  uint32_t *p = (uint32_t *)(src + (int16_t) ins);
+	  if (p == invalid_address)
+	    return false;
+	  gprs [ins >> 21 & 0x1F] = *p;
+	  continue;
+	}
+      if (ins >> 26 == 0x21)  /* lwzu */
+	{
+	  uint32_t *p = (uint32_t *)(gprs [ins >> 16 & 0x1F] += (int16_t) ins);
+	  if (p == invalid_address)
+	    return false;
+	  gprs [ins >> 21 & 0x1F] = *p;
+	  continue;
+	}
+      if (ins >> 26 == 0x24)  /* stw */
+	/* What we hope this is doing is '--in_sigtramp'.  We don't want
+	   to actually store to memory, so just make a note of the
+	   address and refuse to load from it.  */
+	{
+	  reg_unit src = (ins >> 16 & 0x1F) == 0 ? 0 : gprs [ins >> 16 & 0x1F];
+	  uint32_t *p = (uint32_t *)(src + (int16_t) ins);
+	  if (p == NULL || invalid_address != NULL)
+	    return false;
+	  invalid_address = p;
+	  continue;
+	}
+      if (ins >> 26 == 0x2E) /* lmw */
+	{
+	  reg_unit src = (ins >> 16 & 0x1F) == 0 ? 0 : gprs [ins >> 16 & 0x1F];
+	  uint32_t *p = (uint32_t *)(src + (int16_t) ins);
+	  int i;
+
+	  for (i = (ins >> 21 & 0x1F); i < 32; i++)
+	    {
+	      if (p == invalid_address)
+		return false;
+	      gprs[i] = *p++;
+	    }
+	  continue;
+	}
+      if ((ins & 0xFC1FFFFF) == 0x7c0803a6)  /* mtlr */
+	{
+	  lr = gprs [ins >> 21 & 0x1F];
+	  continue;
+	}
+      if ((ins & 0xFC1FFFFF) == 0x7c0802a6)  /* mflr */
+	{
+	  gprs [ins >> 21 & 0x1F] = lr;
+	  continue;
+	}
+      if ((ins & 0xFC1FFFFF) == 0x7c0903a6)  /* mtctr */
+	{
+	  ctr = gprs [ins >> 21 & 0x1F];
+	  continue;
+	}
+      /* The PowerPC User's Manual says that bit 11 of the mtcrf
+	 instruction is reserved and should be set to zero, but it
+	 looks like the Darwin assembler doesn't do that... */
+      if ((ins & 0xFC000FFF) == 0x7c000120) /* mtcrf */
+	{
+	  int i;
+	  uint32_t mask = 0;
+	  for (i = 0; i < 8; i++)
+	    mask |= ((-(ins >> (12 + i) & 1)) & 0xF) << 4 * i;
+	  cr = (cr & ~mask) | (gprs [ins >> 21 & 0x1F] & mask);
+	  continue;
+	}
+      if (ins == 0x429f0005)  /* bcl- 20,4*cr7+so,.+4, loads pc into LR */
+	{
+	  lr = (reg_unit) pc;
+	  continue;
+	}
+      if (ins == 0x4e800420) /* bctr */
+	{
+	  pc = (uint32_t *) ctr;
+	  continue;
+	}
+      if (ins == 0x44000002) /* sc */
+	return true;
+
+      return false;
+    }
+}
+
+/* These defines are from the kernel's bsd/dev/ppc/unix_signal.c.  */
+#define UC_TRAD                 1
+#define UC_TRAD_VEC             6
+#define UC_TRAD64               20
+#define UC_TRAD64_VEC           25
+#define UC_FLAVOR               30
+#define UC_FLAVOR_VEC           35
+#define UC_FLAVOR64             40
+#define UC_FLAVOR64_VEC         45
+#define UC_DUAL                 50
+#define UC_DUAL_VEC             55
+
+/* These are based on /usr/include/ppc/ucontext.h and
+   /usr/include/mach/ppc/thread_status.h, but rewritten to be more
+   convenient, to compile on Jaguar, and to work around Radar 3712064
+   on Panther, which is that the 'es' field of 'struct mcontext64' has
+   the wrong type (doh!).  */
+
+struct gcc_mcontext64 {
+  uint64_t dar;
+  uint32_t dsisr;
+  uint32_t exception;
+  uint32_t padding1[4];
+  uint64_t srr0;
+  uint64_t srr1;
+  uint32_t gpr[32][2];
+  uint32_t cr;
+  uint32_t xer[2];  /* These are arrays because the original structure has them misaligned.  */
+  uint32_t lr[2];
+  uint32_t ctr[2];
+  uint32_t vrsave;
+  ppc_float_state_t fs;
+  ppc_vector_state_t vs;
+};
+
+#define UC_FLAVOR_SIZE \
+  (sizeof (struct mcontext) - sizeof (ppc_vector_state_t))
+
+#define UC_FLAVOR_VEC_SIZE (sizeof (struct mcontext))
+
+#define UC_FLAVOR64_SIZE \
+  (sizeof (struct gcc_mcontext64) - sizeof (ppc_vector_state_t))
+
+#define UC_FLAVOR64_VEC_SIZE (sizeof (struct gcc_mcontext64))
+
+/* Given GPRS as input to a 'sc' instruction, and OLD_CFA, update FS
+   to represent the execution of a signal return; or, if not a signal
+   return, return false.  */
+
+static bool
+handle_syscall (_Unwind_FrameState *fs, const reg_unit gprs[32],
+		_Unwind_Ptr old_cfa)
+{
+  struct ucontext *uctx;
+  bool is_64, is_vector;
+  ppc_float_state_t *float_state;
+  ppc_vector_state_t *vector_state;
+  _Unwind_Ptr new_cfa;
+  int i;
+  static _Unwind_Ptr return_addr;
+  
+  /* Yay!  We're in a Libc that we understand, and it's made a
+     system call.  It'll be one of two kinds: either a Jaguar-style
+     SYS_sigreturn, or a Panther-style 'syscall' call with 184, which 
+     is also SYS_sigreturn.  */
+  
+  if (gprs[0] == 0x67 /* SYS_SIGRETURN */)
+    {
+      uctx = (struct ucontext *) gprs[3];
+      is_vector = (uctx->uc_mcsize == UC_FLAVOR64_VEC_SIZE
+		   || uctx->uc_mcsize == UC_FLAVOR_VEC_SIZE);
+      is_64 = (uctx->uc_mcsize == UC_FLAVOR64_VEC_SIZE
+	       || uctx->uc_mcsize == UC_FLAVOR64_SIZE);
+    }
+  else if (gprs[0] == 0 && gprs[3] == 184)
+    {
+      int ctxstyle = gprs[5];
+      uctx = (struct ucontext *) gprs[4];
+      is_vector = (ctxstyle == UC_FLAVOR_VEC || ctxstyle == UC_FLAVOR64_VEC
+		   || ctxstyle == UC_TRAD_VEC || ctxstyle == UC_TRAD64_VEC);
+      is_64 = (ctxstyle == UC_FLAVOR64_VEC || ctxstyle == UC_TRAD64_VEC
+	       || ctxstyle == UC_FLAVOR64 || ctxstyle == UC_TRAD64);
+    }
+  else
+    return false;
+
+#define set_offset(r, addr)					\
+  (fs->regs.reg[r].how = REG_SAVED_OFFSET,			\
+   fs->regs.reg[r].loc.offset = (_Unwind_Ptr)(addr) - new_cfa)
+
+  /* Restore even the registers that are not call-saved, since they
+     might be being used in the prologue to save other registers,
+     for instance GPR0 is sometimes used to save LR.  */
+
+  /* Handle the GPRs, and produce the information needed to do the rest.  */
+  if (is_64)
+    {
+      /* The context is 64-bit, but it doesn't carry any extra information
+	 for us because only the low 32 bits of the registers are
+	 call-saved.  */
+      struct gcc_mcontext64 *m64 = (struct gcc_mcontext64 *)uctx->uc_mcontext;
+      int i;
+
+      float_state = &m64->fs;
+      vector_state = &m64->vs;
+
+      new_cfa = m64->gpr[1][1];
+      
+      set_offset (CR2_REGNO, &m64->cr);
+      for (i = 0; i < 32; i++)
+	set_offset (i, m64->gpr[i] + 1);
+      set_offset (XER_REGNO, m64->xer + 1);
+      set_offset (LINK_REGISTER_REGNUM, m64->lr + 1);
+      set_offset (COUNT_REGISTER_REGNUM, m64->ctr + 1);
+      if (is_vector)
+	set_offset (VRSAVE_REGNO, &m64->vrsave);
+      
+      /* Sometimes, srr0 points to the instruction that caused the exception,
+	 and sometimes to the next instruction to be executed; we want
+	 the latter.  */
+      if (m64->exception == 3 || m64->exception == 4
+	  || m64->exception == 6
+	  || (m64->exception == 7 && !(m64->srr1 & 0x10000)))
+	return_addr = m64->srr0 + 4;
+      else
+	return_addr = m64->srr0;
+    }
+  else
+    {
+      struct mcontext *m = uctx->uc_mcontext;
+      int i;
+
+      float_state = &m->fs;
+      vector_state = &m->vs;
+      
+      new_cfa = m->ss.r1;
+
+      set_offset (CR2_REGNO, &m->ss.cr);
+      for (i = 0; i < 32; i++)
+	set_offset (i, &m->ss.r0 + i);
+      set_offset (XER_REGNO, &m->ss.xer);
+      set_offset (LINK_REGISTER_REGNUM, &m->ss.lr);
+      set_offset (COUNT_REGISTER_REGNUM, &m->ss.ctr);
+
+      if (is_vector)
+	set_offset (VRSAVE_REGNO, &m->ss.vrsave);
+
+      /* Sometimes, srr0 points to the instruction that caused the exception,
+	 and sometimes to the next instruction to be executed; we want
+	 the latter.  */
+      if (m->es.exception == 3 || m->es.exception == 4
+	  || m->es.exception == 6
+	  || (m->es.exception == 7 && !(m->ss.srr1 & 0x10000)))
+	return_addr = m->ss.srr0 + 4;
+      else
+	return_addr = m->ss.srr0;
+    }
+
+  fs->cfa_how = CFA_REG_OFFSET;
+  fs->cfa_reg = STACK_POINTER_REGNUM;
+  fs->cfa_offset = new_cfa - old_cfa;;
+  
+  /* The choice of column for the return address is somewhat tricky.
+     Fortunately, the actual choice is private to this file, and
+     the space it's reserved from is the GCC register space, not the
+     DWARF2 numbering.  So any free element of the right size is an OK
+     choice.  Thus: */
+  fs->retaddr_column = ARG_POINTER_REGNUM;
+  /* FIXME: this should really be done using a DWARF2 location expression,
+     not using a static variable.  In fact, this entire file should
+     be implemented in DWARF2 expressions.  */
+  set_offset (ARG_POINTER_REGNUM, &return_addr);
+
+  for (i = 0; i < 32; i++)
+    set_offset (32 + i, float_state->fpregs + i);
+  set_offset (SPEFSCR_REGNO, &float_state->fpscr);
+  
+  if (is_vector)
+    {
+      for (i = 0; i < 32; i++)
+	set_offset (FIRST_ALTIVEC_REGNO + i, vector_state->save_vr + i);
+      set_offset (VSCR_REGNO, vector_state->save_vscr);
+    }
+
+  return true;
+}
+
+/* This is also prototyped in rs6000/darwin.h, inside the
+   MD_FALLBACK_FRAME_STATE_FOR macro.  */
+extern bool _Unwind_fallback_frame_state_for (struct _Unwind_Context *context,
+					      _Unwind_FrameState *fs);
+
+/* Implement the MD_FALLBACK_FRAME_STATE_FOR macro,
+   returning true iff the frame was a sigreturn() frame that we
+   can understand.  */
+
+bool
+_Unwind_fallback_frame_state_for (struct _Unwind_Context *context,
+				  _Unwind_FrameState *fs)
+{
+  reg_unit gprs[32];
+
+  if (!interpret_libc (gprs, context))
+    return false;
+  return handle_syscall (fs, gprs, _Unwind_GetCFA (context));
+}
diff --git a/gcc/config/rs6000/darwin.h b/gcc/config/rs6000/darwin.h
index b5c9b8701008af07ab8c4eef67122503e831bf57..ae65eb26851e91455747de5b2e4e8fb1bc6d9ec5 100644
--- a/gcc/config/rs6000/darwin.h
+++ b/gcc/config/rs6000/darwin.h
@@ -327,3 +327,17 @@ do {									\
 #undef REGISTER_TARGET_PRAGMAS
 #define REGISTER_TARGET_PRAGMAS DARWIN_REGISTER_TARGET_PRAGMAS
 
+#ifdef IN_LIBGCC2
+#include <stdbool.h>
+#endif
+
+#define MD_FALLBACK_FRAME_STATE_FOR(CONTEXT, FS, SUCCESS)		\
+  {									\
+    extern bool _Unwind_fallback_frame_state_for			\
+      (struct _Unwind_Context *context, _Unwind_FrameState *fs);	\
+									\
+    if (_Unwind_fallback_frame_state_for (CONTEXT, FS))			\
+      goto SUCCESS;							\
+  }
+
+#define HAS_MD_FALLBACK_FRAME_STATE_FOR 1
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 5b7cd3f1723bc7c373cb921585a6503d0ff7018e..47c9bed2e7d123f93e6884cc6afbad10b5069e61 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -12298,14 +12298,31 @@ rs6000_emit_prologue (void)
 
   /* If we use the link register, get it into r0.  */
   if (info->lr_save_p)
-    emit_move_insn (gen_rtx_REG (Pmode, 0),
-		    gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM));
+    {
+      insn = emit_move_insn (gen_rtx_REG (Pmode, 0),
+			     gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM));
+      RTX_FRAME_RELATED_P (insn) = 1;
+    }
 
   /* If we need to save CR, put it into r12.  */
   if (info->cr_save_p && frame_reg_rtx != frame_ptr_rtx)
     {
+      rtx set;
+      
       cr_save_rtx = gen_rtx_REG (SImode, 12);
-      emit_insn (gen_movesi_from_cr (cr_save_rtx));
+      insn = emit_insn (gen_movesi_from_cr (cr_save_rtx));
+      RTX_FRAME_RELATED_P (insn) = 1;
+      /* Now, there's no way that dwarf2out_frame_debug_expr is going
+	 to understand '(unspec:SI [(reg:CC 68) ...] UNSPEC_MOVESI_FROM_CR)'.
+	 But that's OK.  All we have to do is specify that _one_ condition
+	 code register is saved in this stack slot.  The thrower's epilogue
+	 will then restore all the call-saved registers.
+	 We use CR2_REGNO (70) to be compatible with gcc-2.95 on Linux.  */
+      set = gen_rtx_SET (VOIDmode, cr_save_rtx,
+			 gen_rtx_REG (SImode, CR2_REGNO));
+      REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR,
+					    set,
+					    REG_NOTES (insn));
     }
 
   /* Do any required saving of fpr's.  If only one or two to save, do
@@ -12484,7 +12501,7 @@ rs6000_emit_prologue (void)
       
       insn = emit_move_insn (mem, reg);
       rs6000_frame_related (insn, frame_ptr_rtx, info->total_size, 
-			    reg, gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM));
+			    NULL_RTX, NULL_RTX);
     }
 
   /* Save CR if we use any that must be preserved.  */
@@ -12493,6 +12510,8 @@ rs6000_emit_prologue (void)
       rtx addr = gen_rtx_PLUS (Pmode, frame_reg_rtx,
 			       GEN_INT (info->cr_save_offset + sp_offset));
       rtx mem = gen_rtx_MEM (SImode, addr);
+      /* See the large comment above about why CR2_REGNO is used.  */
+      rtx magic_eh_cr_reg = gen_rtx_REG (SImode, CR2_REGNO);
 
       set_mem_alias_set (mem, rs6000_sr_alias_set);
 
@@ -12500,19 +12519,21 @@ rs6000_emit_prologue (void)
 	 that it's free.  */
       if (REGNO (frame_reg_rtx) == 12)
 	{
+	  rtx set;
+
 	  cr_save_rtx = gen_rtx_REG (SImode, 0);
-	  emit_insn (gen_movesi_from_cr (cr_save_rtx));
+	  insn = emit_insn (gen_movesi_from_cr (cr_save_rtx));
+	  RTX_FRAME_RELATED_P (insn) = 1;
+	  set = gen_rtx_SET (VOIDmode, cr_save_rtx, magic_eh_cr_reg);
+	  REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR,
+						set,
+						REG_NOTES (insn));
+	  
 	}
       insn = emit_move_insn (mem, cr_save_rtx);
 
-      /* Now, there's no way that dwarf2out_frame_debug_expr is going
-	 to understand '(unspec:SI [(reg:CC 68) ...] UNSPEC_MOVESI_FROM_CR)'.
-	 But that's OK.  All we have to do is specify that _one_ condition
-	 code register is saved in this stack slot.  The thrower's epilogue
-	 will then restore all the call-saved registers.
-	 We use CR2_REGNO (70) to be compatible with gcc-2.95 on Linux.  */
       rs6000_frame_related (insn, frame_ptr_rtx, info->total_size, 
-			    cr_save_rtx, gen_rtx_REG (SImode, CR2_REGNO));
+			    NULL_RTX, NULL_RTX);
     }
 
   /* Update stack and set back pointer unless this is V.4, 
@@ -12546,9 +12567,16 @@ rs6000_emit_prologue (void)
     if (save_LR_around_toc_setup)
       {
 	rtx lr = gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM);
-	rs6000_maybe_dead (emit_move_insn (frame_ptr_rtx, lr));
+
+	insn = emit_move_insn (frame_ptr_rtx, lr);
+	rs6000_maybe_dead (insn);
+	RTX_FRAME_RELATED_P (insn) = 1;
+
 	rs6000_emit_load_toc_table (TRUE);
-	rs6000_maybe_dead (emit_move_insn (lr, frame_ptr_rtx));
+
+	insn = emit_move_insn (lr, frame_ptr_rtx);
+	rs6000_maybe_dead (insn);
+	RTX_FRAME_RELATED_P (insn) = 1;
       }
     else
       rs6000_emit_load_toc_table (TRUE);
@@ -12558,15 +12586,16 @@ rs6000_emit_prologue (void)
   if (DEFAULT_ABI == ABI_DARWIN
       && flag_pic && current_function_uses_pic_offset_table)
     {
-      rtx dest = gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM);
+      rtx lr = gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM);
       const char *picbase = machopic_function_base_name ();
       rtx src = gen_rtx_SYMBOL_REF (Pmode, picbase);
 
-      rs6000_maybe_dead (emit_insn (gen_load_macho_picbase (dest, src)));
+      rs6000_maybe_dead (emit_insn (gen_load_macho_picbase (lr, src)));
 
-      rs6000_maybe_dead (
-	emit_move_insn (gen_rtx_REG (Pmode, RS6000_PIC_OFFSET_TABLE_REGNUM),
-			gen_rtx_REG (Pmode, LINK_REGISTER_REGNUM)));
+      insn = emit_move_insn (gen_rtx_REG (Pmode, 
+					  RS6000_PIC_OFFSET_TABLE_REGNUM),
+			     lr);
+      rs6000_maybe_dead (insn);
     }
 #endif
 }
diff --git a/gcc/config/rs6000/t-darwin b/gcc/config/rs6000/t-darwin
index 3302176c93d52ad62bdbabf0965d83ddd718c9d7..f38adb92a33f6a470ccdd55c35fcadddcaae741c 100644
--- a/gcc/config/rs6000/t-darwin
+++ b/gcc/config/rs6000/t-darwin
@@ -1,6 +1,6 @@
-# Add trampoline and long double support to libgcc.
 LIB2FUNCS_EXTRA = $(srcdir)/config/rs6000/darwin-tramp.asm \
-	$(srcdir)/config/rs6000/darwin-ldouble.c
+	$(srcdir)/config/rs6000/darwin-ldouble.c \
+	$(srcdir)/config/rs6000/darwin-fallback.c
 
 LIB2FUNCS_STATIC_EXTRA = \
 	$(srcdir)/config/rs6000/darwin-fpsave.asm  \
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 17b4c2060c0f8d79d439bb13e3084fc7a428ef60..8549c7d453c46ac81de046b5d9d2f755ab776d1f 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -359,7 +359,6 @@ static HOST_WIDE_INT stack_adjust_offset (rtx);
 static void output_cfi (dw_cfi_ref, dw_fde_ref, int);
 static void output_call_frame_info (int);
 static void dwarf2out_stack_adjust (rtx);
-static void queue_reg_save (const char *, rtx, HOST_WIDE_INT);
 static void flush_queued_reg_saves (void);
 static bool clobbers_queued_reg_save (rtx);
 static void dwarf2out_frame_debug_expr (rtx, const char *);
@@ -843,8 +842,7 @@ reg_save (const char *label, unsigned int reg, unsigned int sreg, HOST_WIDE_INT
       cfi->dw_cfi_oprnd2.dw_cfi_offset = offset;
     }
   else if (sreg == reg)
-    /* We could emit a DW_CFA_same_value in this case, but don't bother.  */
-    return;
+    cfi->dw_cfi_opc = DW_CFA_same_value;
   else
     {
       cfi->dw_cfi_opc = DW_CFA_register;
@@ -974,7 +972,8 @@ initial_return_save (rtx rtl)
       abort ();
     }
 
-  reg_save (NULL, DWARF_FRAME_RETURN_COLUMN, reg, offset - cfa.offset);
+  if (reg != DWARF_FRAME_RETURN_COLUMN)
+    reg_save (NULL, DWARF_FRAME_RETURN_COLUMN, reg, offset - cfa.offset);
 }
 
 /* Given a SET, calculate the amount of stack adjustment it
@@ -1144,53 +1143,134 @@ struct queued_reg_save GTY(())
   struct queued_reg_save *next;
   rtx reg;
   HOST_WIDE_INT cfa_offset;
+  rtx saved_reg;
 };
 
 static GTY(()) struct queued_reg_save *queued_reg_saves;
 
+/* The caller's ORIG_REG is saved in SAVED_IN_REG.  */
+struct reg_saved_in_data GTY(()) {
+  rtx orig_reg;
+  rtx saved_in_reg;
+};
+
+/* A list of registers saved in other registers.
+   The list intentionally has a small maximum capacity of 4; if your
+   port needs more than that, you might consider implementing a
+   more efficient data structure.  */
+static GTY(()) struct reg_saved_in_data regs_saved_in_regs[4];
+static GTY(()) size_t num_regs_saved_in_regs;
+  
 #if defined (DWARF2_DEBUGGING_INFO) || defined (DWARF2_UNWIND_INFO)
 static const char *last_reg_save_label;
 
+/* Add an entry to QUEUED_REG_SAVES saying that REG is now saved at
+   SREG, or if SREG is NULL then it is saved at OFFSET to the CFA.  */
+
 static void
-queue_reg_save (const char *label, rtx reg, HOST_WIDE_INT offset)
+queue_reg_save (const char *label, rtx reg, rtx sreg, HOST_WIDE_INT offset)
 {
-  struct queued_reg_save *q = ggc_alloc (sizeof (*q));
+  struct queued_reg_save *q;
+
+  /* Duplicates waste space, but it's also necessary to remove them
+     for correctness, since the queue gets output in reverse
+     order.  */
+  for (q = queued_reg_saves; q != NULL; q = q->next)
+    if (REGNO (q->reg) == REGNO (reg))
+      break;
+
+  if (q == NULL)
+    {
+      q = ggc_alloc (sizeof (*q));
+      q->next = queued_reg_saves;
+      queued_reg_saves = q;
+    }
 
-  q->next = queued_reg_saves;
   q->reg = reg;
   q->cfa_offset = offset;
-  queued_reg_saves = q;
+  q->saved_reg = sreg;
 
   last_reg_save_label = label;
 }
 
+/* Output all the entries in QUEUED_REG_SAVES.  */
+
 static void
 flush_queued_reg_saves (void)
 {
-  struct queued_reg_save *q, *next;
+  struct queued_reg_save *q;
 
-  for (q = queued_reg_saves; q; q = next)
+  for (q = queued_reg_saves; q; q = q->next)
     {
-      dwarf2out_reg_save (last_reg_save_label, REGNO (q->reg), q->cfa_offset);
-      next = q->next;
+      size_t i;
+      for (i = 0; i < num_regs_saved_in_regs; i++)
+	if (REGNO (regs_saved_in_regs[i].orig_reg) == REGNO (q->reg))
+	  break;
+      if (q->saved_reg && i == num_regs_saved_in_regs)
+	{
+	  if (i == ARRAY_SIZE (regs_saved_in_regs))
+	    abort ();
+	  num_regs_saved_in_regs++;
+	}
+      if (i != num_regs_saved_in_regs)
+	{
+	  regs_saved_in_regs[i].orig_reg = q->reg;
+	  regs_saved_in_regs[i].saved_in_reg = q->saved_reg;
+	}
+
+      reg_save (last_reg_save_label, REGNO (q->reg), 
+		q->saved_reg ? REGNO (q->saved_reg) : -1U, q->cfa_offset);
     }
 
   queued_reg_saves = NULL;
   last_reg_save_label = NULL;
 }
 
+/* Does INSN clobber any register which QUEUED_REG_SAVES lists a saved
+   location for?  Or, does it clobber a register which we've previously
+   said that some other register is saved in, and for which we now
+   have a new location for?  */
+
 static bool
 clobbers_queued_reg_save (rtx insn)
 {
   struct queued_reg_save *q;
 
   for (q = queued_reg_saves; q; q = q->next)
-    if (modified_in_p (q->reg, insn))
-      return true;
+    {
+      size_t i;
+      if (modified_in_p (q->reg, insn))
+	return true;
+      for (i = 0; i < num_regs_saved_in_regs; i++)
+	if (REGNO (q->reg) == REGNO (regs_saved_in_regs[i].orig_reg)
+	    && modified_in_p (regs_saved_in_regs[i].saved_in_reg, insn))
+	  return true;
+    }
 
   return false;
 }
 
+/* What register, if any, is currently saved in REG?  */
+
+static rtx
+reg_saved_in (rtx reg)
+{
+  unsigned int regn = REGNO (reg);
+  size_t i;
+  struct queued_reg_save *q;
+  
+  for (q = queued_reg_saves; q; q = q->next)
+    if (q->saved_reg && regn == REGNO (q->saved_reg))
+      return q->reg;
+
+  for (i = 0; i < num_regs_saved_in_regs; i++)
+    if (regs_saved_in_regs[i].saved_in_reg
+	&& regn == REGNO (regs_saved_in_regs[i].saved_in_reg))
+      return regs_saved_in_regs[i].orig_reg;
+
+  return NULL_RTX;
+}
+
 
 /* A temporary register holding an integral value used in adjusting SP
    or setting up the store_reg.  The "offset" field holds the integer
@@ -1199,8 +1279,8 @@ static dw_cfa_location cfa_temp;
 
 /* Record call frame debugging information for an expression EXPR,
    which either sets SP or FP (adjusting how we calculate the frame
-   address) or saves a register to the stack.  LABEL indicates the
-   address of EXPR.
+   address) or saves a register to the stack or another register.
+   LABEL indicates the address of EXPR.
 
    This function encodes a state machine mapping rtxes to actions on
    cfa, cfa_store, and cfa_temp.reg.  We describe these rules so
@@ -1224,12 +1304,20 @@ static dw_cfa_location cfa_temp;
   RTX_FRAME_RELATED_P is set on an insn which modifies memory, it's a
   register save, and the register used to calculate the destination
   had better be the one we think we're using for this purpose.
+  It's also assumed that a copy from a call-saved register to another
+  register is saving that register if RTX_FRAME_RELATED_P is set on
+  that instruction.  If the copy is from a call-saved register to
+  the *same* register, that means that the register is now the same
+  value as in the caller.
 
   Except: If the register being saved is the CFA register, and the
   offset is nonzero, we are saving the CFA, so we assume we have to
   use DW_CFA_def_cfa_expression.  If the offset is 0, we assume that
   the intent is to save the value of SP from the previous frame.
 
+  In addition, if a register has previously been saved to a different
+  register, 
+
   Invariants / Summaries of Rules
 
   cfa	       current rule for calculating the CFA.  It usually
@@ -1380,29 +1468,42 @@ dwarf2out_frame_debug_expr (rtx expr, const char *label)
   src = SET_SRC (expr);
   dest = SET_DEST (expr);
 
+  if (GET_CODE (src) == REG)
+    {
+      rtx rsi = reg_saved_in (src);
+      if (rsi)
+	src = rsi;
+    }
+
   switch (GET_CODE (dest))
     {
     case REG:
-      /* Rule 1 */
-      /* Update the CFA rule wrt SP or FP.  Make sure src is
-	 relative to the current CFA register.  */
       switch (GET_CODE (src))
 	{
 	  /* Setting FP from SP.  */
 	case REG:
 	  if (cfa.reg == (unsigned) REGNO (src))
-	    /* OK.  */
-	    ;
+	    {
+	      /* Rule 1 */
+	      /* Update the CFA rule wrt SP or FP.  Make sure src is
+		 relative to the current CFA register. 
+
+		 We used to require that dest be either SP or FP, but the
+		 ARM copies SP to a temporary register, and from there to
+		 FP.  So we just rely on the backends to only set
+		 RTX_FRAME_RELATED_P on appropriate insns.  */
+	      cfa.reg = REGNO (dest);
+	      cfa_temp.reg = cfa.reg;
+	      cfa_temp.offset = cfa.offset;
+	    }
+	  else if (call_used_regs [REGNO (dest)] 
+		   && ! fixed_regs [REGNO (dest)])
+	    {
+	      /* Saving a register in a register.  */
+	      queue_reg_save (label, src, dest, 0);
+	    }
 	  else
 	    abort ();
-
-	  /* We used to require that dest be either SP or FP, but the
-	     ARM copies SP to a temporary register, and from there to
-	     FP.  So we just rely on the backends to only set
-	     RTX_FRAME_RELATED_P on appropriate insns.  */
-	  cfa.reg = REGNO (dest);
-	  cfa_temp.reg = cfa.reg;
-	  cfa_temp.offset = cfa.offset;
 	  break;
 
 	case PLUS:
@@ -1642,7 +1743,7 @@ dwarf2out_frame_debug_expr (rtx expr, const char *label)
 		 we're saving SP like any other register; this happens
 		 on the ARM.  */
 	      def_cfa_1 (label, &cfa);
-	      queue_reg_save (label, stack_pointer_rtx, offset);
+	      queue_reg_save (label, stack_pointer_rtx, NULL_RTX, offset);
 	      break;
 	    }
 	  else
@@ -1665,7 +1766,7 @@ dwarf2out_frame_debug_expr (rtx expr, const char *label)
 	}
 
       def_cfa_1 (label, &cfa);
-      queue_reg_save (label, src, offset);
+      queue_reg_save (label, src, NULL_RTX, offset);
       break;
 
     default:
@@ -1685,6 +1786,8 @@ dwarf2out_frame_debug (rtx insn)
 
   if (insn == NULL_RTX)
     {
+      size_t i;
+      
       /* Flush any queued register saves.  */
       flush_queued_reg_saves ();
 
@@ -1697,6 +1800,13 @@ dwarf2out_frame_debug (rtx insn)
       cfa_store = cfa;
       cfa_temp.reg = -1;
       cfa_temp.offset = 0;
+      
+      for (i = 0; i < num_regs_saved_in_regs; i++)
+	{
+	  regs_saved_in_regs[i].orig_reg = NULL_RTX;
+	  regs_saved_in_regs[i].saved_in_reg = NULL_RTX;
+	}
+      num_regs_saved_in_regs = 0;
       return;
     }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index b08ec7d199d21ed01403b84d2e3c892606db0b89..926c9cd8b7f9989b2c6c9f1053b1182fb7576cd1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,14 @@
+2004-06-26  Geoffrey Keating  <geoffk@apple.com>
+	    Andreas Tobler  <a.tobler@schweiz.ch>
+
+	* gcc.dg/cleanup-10.c: Run on all Linux platforms and powerpc-darwin.
+	Use SA_RESETHAND rather than SA_ONESHOT.  Trap SIGBUS as well
+	as SIGSEGV.
+	* gcc.dg/cleanup-11.c: Likewise.
+	* gcc.dg/cleanup-8.c: Likewise.
+	* gcc.dg/cleanup-9.c: Likewise.
+	* gcc.dg/cleanup-5.c: Run on all platforms.
+
 2004-06-30  Joseph S. Myers  <jsm@polyomino.org.uk>
 
 	* g++.dg/warn/nonnull1.C: New test.
diff --git a/gcc/testsuite/gcc.dg/cleanup-10.c b/gcc/testsuite/gcc.dg/cleanup-10.c
index 39923fdde15dc26f7d607402ca2d0807f29cc417..76470e615816b7d19df32cb87f1864fff8fd4fa2 100644
--- a/gcc/testsuite/gcc.dg/cleanup-10.c
+++ b/gcc/testsuite/gcc.dg/cleanup-10.c
@@ -1,4 +1,4 @@
-/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* mips*-*-linux* } } */
+/* { dg-do run { target *-*-linux* powerpc*-*-darwin* } } */
 /* { dg-options "-fasynchronous-unwind-tables -fexceptions -O2" } */
 /* Verify that cleanups work with exception handling through signal frames
    on alternate stack.  */
@@ -93,8 +93,9 @@ static int __attribute__((noinline)) fn1 ()
 
   sigemptyset (&s.sa_mask);
   s.sa_sigaction = fn4;
-  s.sa_flags = SA_ONESHOT | SA_ONSTACK;
+  s.sa_flags = SA_RESETHAND | SA_ONSTACK;
   sigaction (SIGSEGV, &s, NULL);
+  sigaction (SIGBUS, &s, NULL);
   fn2 ();
   return 0;
 }
diff --git a/gcc/testsuite/gcc.dg/cleanup-11.c b/gcc/testsuite/gcc.dg/cleanup-11.c
index 9c47f6cf6588eb71389a7f806ba5f8538a265983..4ad131f00ae893d10130cfba42447b9769656f6f 100644
--- a/gcc/testsuite/gcc.dg/cleanup-11.c
+++ b/gcc/testsuite/gcc.dg/cleanup-11.c
@@ -1,4 +1,4 @@
-/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* mips*-*-linux* } } */
+/* { dg-do run { target *-*-linux* powerpc*-*-darwin* } } */
 /* { dg-options "-fasynchronous-unwind-tables -fexceptions -O2" } */
 /* Verify that cleanups work with exception handling through realtime signal
    frames on alternate stack.  */
@@ -93,8 +93,9 @@ static int __attribute__((noinline)) fn1 ()
 
   sigemptyset (&s.sa_mask);
   s.sa_sigaction = fn4;
-  s.sa_flags = SA_ONESHOT | SA_ONSTACK | SA_SIGINFO;
+  s.sa_flags = SA_RESETHAND | SA_ONSTACK | SA_SIGINFO;
   sigaction (SIGSEGV, &s, NULL);
+  sigaction (SIGBUS, &s, NULL);
   fn2 ();
   return 0;
 }
diff --git a/gcc/testsuite/gcc.dg/cleanup-5.c b/gcc/testsuite/gcc.dg/cleanup-5.c
index 4b8468aa7335c22e76caae5041116c6f67edd5c0..f5306db47526af3822f13f03b49097edc3a02c74 100644
--- a/gcc/testsuite/gcc.dg/cleanup-5.c
+++ b/gcc/testsuite/gcc.dg/cleanup-5.c
@@ -1,4 +1,4 @@
-/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* mips*-*-linux* } } */
+/* { dg-do run } */
 /* { dg-options "-fexceptions" } */
 /* Verify that cleanups work with exception handling.  */
 
diff --git a/gcc/testsuite/gcc.dg/cleanup-8.c b/gcc/testsuite/gcc.dg/cleanup-8.c
index 91e387ce799e51642b71c8c64d89edc4af942b6d..b802d25ead179b4939f46ac50517c20dc786ffa7 100644
--- a/gcc/testsuite/gcc.dg/cleanup-8.c
+++ b/gcc/testsuite/gcc.dg/cleanup-8.c
@@ -1,4 +1,4 @@
-/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* } } */
+/* { dg-do run { target *-*-linux* powerpc*-*-darwin* } } */
 /* { dg-options "-fasynchronous-unwind-tables -fexceptions -O2" } */
 /* Verify that cleanups work with exception handling through signal
    frames.  */
@@ -78,6 +78,7 @@ static int __attribute__((noinline)) fn2 ()
 static int __attribute__((noinline)) fn1 ()
 {
   signal (SIGSEGV, fn4);
+  signal (SIGBUS, fn4);
   fn2 ();
   return 0;
 }
diff --git a/gcc/testsuite/gcc.dg/cleanup-9.c b/gcc/testsuite/gcc.dg/cleanup-9.c
index 29048d2f78ae156e47799b4ac5cfd07f424a5f64..2381e955e44d1a39130cf417efd347a3ea8355a4 100644
--- a/gcc/testsuite/gcc.dg/cleanup-9.c
+++ b/gcc/testsuite/gcc.dg/cleanup-9.c
@@ -1,4 +1,4 @@
-/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* mips*-*-linux* } } */
+/* { dg-do run { target *-*-linux* powerpc*-*-darwin* } } */
 /* { dg-options "-fasynchronous-unwind-tables -fexceptions -O2" } */
 /* Verify that cleanups work with exception handling through realtime
    signal frames.  */
@@ -80,8 +80,9 @@ static int __attribute__((noinline)) fn1 ()
   struct sigaction s;
   sigemptyset (&s.sa_mask);
   s.sa_sigaction = fn4;
-  s.sa_flags = SA_ONESHOT | SA_SIGINFO;
+  s.sa_flags = SA_RESETHAND | SA_SIGINFO;
   sigaction (SIGSEGV, &s, NULL);
+  sigaction (SIGBUS, &s, NULL);
   fn2 ();
   return 0;
 }
diff --git a/gcc/unwind-dw2.c b/gcc/unwind-dw2.c
index b99b7007a00ccd9c96b2fa9d2587158b45d06898..11b94b123d0f72d4b20d5708e5c1e817c6cb4b70 100644
--- a/gcc/unwind-dw2.c
+++ b/gcc/unwind-dw2.c
@@ -40,7 +40,7 @@
 #include "unwind-pe.h"
 #include "unwind-dw2-fde.h"
 #include "gthr.h"
-
+#include "unwind-dw2.h"
 
 #ifndef __USING_SJLJ_EXCEPTIONS__
 
@@ -51,12 +51,6 @@
 #define STACK_GROWS_DOWNWARD 1
 #endif
 
-/* A target can override (perhaps for backward compatibility) how
-   many dwarf2 columns are unwound.  */
-#ifndef DWARF_FRAME_REGISTERS
-#define DWARF_FRAME_REGISTERS FIRST_PSEUDO_REGISTER
-#endif
-
 /* Dwarf frame registers used for pre gcc 3.0 compiled glibc.  */
 #ifndef PRE_GCC3_DWARF_FRAME_REGISTERS
 #define PRE_GCC3_DWARF_FRAME_REGISTERS DWARF_FRAME_REGISTERS
@@ -87,58 +81,6 @@ struct _Unwind_Context
 /* Byte size of every register managed by these routines.  */
 static unsigned char dwarf_reg_size_table[DWARF_FRAME_REGISTERS+1];
 
-
-/* The result of interpreting the frame unwind info for a frame.
-   This is all symbolic at this point, as none of the values can
-   be resolved until the target pc is located.  */
-typedef struct
-{
-  /* Each register save state can be described in terms of a CFA slot,
-     another register, or a location expression.  */
-  struct frame_state_reg_info
-  {
-    struct {
-      union {
-	_Unwind_Word reg;
-	_Unwind_Sword offset;
-	const unsigned char *exp;
-      } loc;
-      enum {
-	REG_UNSAVED,
-	REG_SAVED_OFFSET,
-	REG_SAVED_REG,
-	REG_SAVED_EXP
-      } how;
-    } reg[DWARF_FRAME_REGISTERS+1];
-
-    /* Used to implement DW_CFA_remember_state.  */
-    struct frame_state_reg_info *prev;
-  } regs;
-
-  /* The CFA can be described in terms of a reg+offset or a
-     location expression.  */
-  _Unwind_Sword cfa_offset;
-  _Unwind_Word cfa_reg;
-  const unsigned char *cfa_exp;
-  enum {
-    CFA_UNSET,
-    CFA_REG_OFFSET,
-    CFA_EXP
-  } cfa_how;
-
-  /* The PC described by the current frame state.  */
-  void *pc;
-
-  /* The information we care about from the CIE/FDE.  */
-  _Unwind_Personality_Fn personality;
-  _Unwind_Sword data_align;
-  _Unwind_Word code_align;
-  _Unwind_Word retaddr_column;
-  unsigned char fde_encoding;
-  unsigned char lsda_encoding;
-  unsigned char saw_z;
-  void *eh_ptr;
-} _Unwind_FrameState;
 
 /* Read unaligned data from the instruction buffer.  */
 
@@ -866,12 +808,15 @@ execute_cfa_program (const unsigned char *insn_ptr,
 
 	case DW_CFA_restore_extended:
 	  insn_ptr = read_uleb128 (insn_ptr, &reg);
+	  /* FIXME, this is wrong; the CIE might have said that the
+	     register was saved somewhere.  */
 	  fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNSAVED;
 	  break;
 
 	case DW_CFA_undefined:
 	case DW_CFA_same_value:
 	  insn_ptr = read_uleb128 (insn_ptr, &reg);
+	  fs->regs.reg[DWARF_REG_TO_UNWIND_COLUMN(reg)].how = REG_UNSAVED;
 	  break;
 
 	case DW_CFA_nop:
diff --git a/gcc/unwind-dw2.h b/gcc/unwind-dw2.h
new file mode 100644
index 0000000000000000000000000000000000000000..77563e7441488a6a13508e59b391252256a4d4e8
--- /dev/null
+++ b/gcc/unwind-dw2.h
@@ -0,0 +1,88 @@
+/* DWARF2 frame unwind data structure.
+   Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
+   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 into combinations with other programs,
+   and to distribute those combinations 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 a combined
+   executable.)
+
+   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.  */
+
+/* A target can override (perhaps for backward compatibility) how
+   many dwarf2 columns are unwound.  */
+#ifndef DWARF_FRAME_REGISTERS
+#define DWARF_FRAME_REGISTERS FIRST_PSEUDO_REGISTER
+#endif
+
+/* The result of interpreting the frame unwind info for a frame.
+   This is all symbolic at this point, as none of the values can
+   be resolved until the target pc is located.  */
+typedef struct
+{
+  /* Each register save state can be described in terms of a CFA slot,
+     another register, or a location expression.  */
+  struct frame_state_reg_info
+  {
+    struct {
+      union {
+	_Unwind_Word reg;
+	_Unwind_Sword offset;
+	const unsigned char *exp;
+      } loc;
+      enum {
+	REG_UNSAVED,
+	REG_SAVED_OFFSET,
+	REG_SAVED_REG,
+	REG_SAVED_EXP
+      } how;
+    } reg[DWARF_FRAME_REGISTERS+1];
+
+    /* Used to implement DW_CFA_remember_state.  */
+    struct frame_state_reg_info *prev;
+  } regs;
+
+  /* The CFA can be described in terms of a reg+offset or a
+     location expression.  */
+  _Unwind_Sword cfa_offset;
+  _Unwind_Word cfa_reg;
+  const unsigned char *cfa_exp;
+  enum {
+    CFA_UNSET,
+    CFA_REG_OFFSET,
+    CFA_EXP
+  } cfa_how;
+
+  /* The PC described by the current frame state.  */
+  void *pc;
+
+  /* The information we care about from the CIE/FDE.  */
+  _Unwind_Personality_Fn personality;
+  _Unwind_Sword data_align;
+  _Unwind_Word code_align;
+  _Unwind_Word retaddr_column;
+  unsigned char fde_encoding;
+  unsigned char lsda_encoding;
+  unsigned char saw_z;
+  void *eh_ptr;
+} _Unwind_FrameState;
+
diff --git a/libjava/ChangeLog b/libjava/ChangeLog
index 7d43c4878b8d7653d6933b7f7645eed1a24ccb5a..8df39520d91a019fc6f048da4506b56488f4ee57 100644
--- a/libjava/ChangeLog
+++ b/libjava/ChangeLog
@@ -1,3 +1,12 @@
+2004-06-26  Geoffrey Keating  <geoffk@apple.com>
+	    Andreas Tobler  <a.tobler@schweiz.ch>
+
+	* configure.host (powerpc-*-darwin*): New case, define
+	can_unwind_signal.
+	* configure.in (*-*-darwin*): New case, point to darwin-signal.h.
+	* configure: Regenerate.
+	* include/darwin-signal.h: New.
+
 2004-06-30  Jerry Quinn  <jlquinn@optonline.net>
 
 	* java/beans/Statement.java (doExecute): Fix formatting.
diff --git a/libjava/configure b/libjava/configure
index baf065d97a1237cb0aef58fa9fa44c20b4f52c5b..463bd0b085a6edc0d620c4d3e02a7984a908392c 100755
--- a/libjava/configure
+++ b/libjava/configure
@@ -8553,6 +8553,9 @@ case "${host}" in
  mips*-*-linux*)
     SIGNAL_HANDLER=include/mips-signal.h
     ;;
+ *-*-darwin*)
+    SIGNAL_HANDLER=include/darwin-signal.h
+    ;;
  *)
     SIGNAL_HANDLER=include/default-signal.h
     ;;
diff --git a/libjava/configure.host b/libjava/configure.host
index c021d13abedb6d00a14d95af224b8abd0782400d..d008df1d00108d7c78881c1b680c9f5daad2ac61 100644
--- a/libjava/configure.host
+++ b/libjava/configure.host
@@ -232,10 +232,10 @@ EOF
 	    ;;
 	esac
 	;;
-  *-*-darwin*)
+  powerpc*-*-darwin*)
 	enable_hash_synchronization_default=no
 	slow_pthread_self=
-	can_unwind_signal=no
+	can_unwind_signal=yes
 	;;
   *-*-freebsd*)
 	slow_pthread_self=
diff --git a/libjava/configure.in b/libjava/configure.in
index c763b7525f1154a17f1f3ccb1b9a6981a0a3a61f..2eff8f95d6d5921ffded1c0fff376d9f603710d8 100644
--- a/libjava/configure.in
+++ b/libjava/configure.in
@@ -1205,6 +1205,9 @@ case "${host}" in
  mips*-*-linux*)
     SIGNAL_HANDLER=include/mips-signal.h
     ;;
+ *-*-darwin*)
+    SIGNAL_HANDLER=include/darwin-signal.h
+    ;;
  *)
     SIGNAL_HANDLER=include/default-signal.h
     ;;
diff --git a/libjava/include/darwin-signal.h b/libjava/include/darwin-signal.h
new file mode 100644
index 0000000000000000000000000000000000000000..5003e211c241387e38c533f70ae102c586c09492
--- /dev/null
+++ b/libjava/include/darwin-signal.h
@@ -0,0 +1,51 @@
+/* darwin-signal.h - Catch runtime signals and turn them into exceptions,
+   on a Darwin system.  */
+
+/* Copyright (C) 2004  Free Software Foundation
+
+   This file is part of libgcj.
+
+This software is copyrighted work licensed under the terms of the
+Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
+details.  */
+
+/* This file is really more of a specification.  The rest of the system
+   should be arranged so that this Just Works.  */
+
+#ifndef JAVA_SIGNAL_H
+# define JAVA_SIGNAL_H 1
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <signal.h>
+
+typedef void (* SIG_PF)(int);
+
+# define HANDLE_SEGV 1
+# undef HANDLE_FPE
+
+# define SIGNAL_HANDLER(_name)					\
+  static void _name (int _dummy __attribute__ ((unused)))
+
+# define MAKE_THROW_FRAME(_exception)
+
+# define INIT_SEGV				\
+  do {						\
+      struct sigaction sa;			\
+      sa.sa_handler = catch_segv;		\
+      sigemptyset (&sa.sa_mask);		\
+      sa.sa_flags = SA_NODEFER;			\
+      sigaction (SIGBUS, &sa, NULL);		\
+      sigaction (SIGSEGV, &sa, NULL);		\
+    } while (0)
+
+# define INIT_FPE				\
+  do {						\
+      struct sigaction sa;			\
+      sa.sa_handler = catch_fpe;		\
+      sigemptyset (&sa.sa_mask);		\
+      sa.sa_flags = SA_NODEFER;			\
+      sigaction (SIGFPE, &sa, NULL);		\
+    } while (0)
+
+#endif /* JAVA_SIGNAL_H */