X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=gcc%2Fconfig%2Fpa%2Flinux-unwind.h;fp=gcc%2Fconfig%2Fpa%2Flinux-unwind.h;h=733f772c1c77c559ddb848b9d08771d82ebc6c34;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git

diff --git a/gcc/config/pa/linux-unwind.h b/gcc/config/pa/linux-unwind.h
new file mode 100644
index 00000000..733f772c
--- /dev/null
+++ b/gcc/config/pa/linux-unwind.h
@@ -0,0 +1,140 @@
+/* DWARF2 EH unwinding support for PA Linux.
+   Copyright (C) 2004, 2005, 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/>.  */
+
+
+/* Do code reading to identify a signal frame, and set the frame
+   state data appropriately.  See unwind-dw2.c for the structs.  */
+
+/* Don't use this if inhibit_libc is set.
+   The build for this target will fail trying to include missing headers. */
+#ifndef inhibit_libc
+#include <signal.h>
+#include <sys/ucontext.h>
+
+/* Unfortunately, because of various bugs and changes to the kernel,
+   we have several cases to deal with.
+
+   In 2.4, the signal trampoline is 4 words, and (CONTEXT)->ra should
+   point directly at the beginning of the trampoline and struct rt_sigframe.
+
+   In <= 2.6.5-rc2-pa3, the signal trampoline is 9 words, and 
+   (CONTEXT)->ra points at the 4th word in the trampoline structure.  This 
+   is wrong, it should point at the 5th word.  This is fixed in 2.6.5-rc2-pa4.
+
+   To detect these cases, we first take (CONTEXT)->ra, align it to 64-bytes
+   to get the beginning of the signal frame, and then check offsets 0, 4
+   and 5 to see if we found the beginning of the trampoline.  This will
+   tell us how to locate the sigcontext structure.
+
+   Note that with a 2.4 64-bit kernel, the signal context is not properly
+   passed back to userspace so the unwind will not work correctly.  */
+
+#define MD_FALLBACK_FRAME_STATE_FOR pa32_fallback_frame_state
+
+static _Unwind_Reason_Code
+pa32_fallback_frame_state (struct _Unwind_Context *context,
+			   _Unwind_FrameState *fs)
+{
+  unsigned long sp = (unsigned long)context->ra & ~63;
+  unsigned int *pc = (unsigned int *)sp;
+  unsigned long off;
+  _Unwind_Ptr new_cfa;
+  int i;
+  struct sigcontext *sc;
+  struct rt_sigframe {
+    struct siginfo info;
+    struct ucontext uc;
+  } *frame;
+
+  /* rt_sigreturn trampoline:
+     3419000x ldi 0, %r25 or ldi 1, %r25   (x = 0 or 2)
+     3414015a ldi __NR_rt_sigreturn, %r20
+     e4008200 be,l 0x100(%sr2, %r0), %sr0, %r31
+     08000240 nop  */
+
+  if (pc[0] == 0x34190000 || pc[0] == 0x34190002)
+    off = 4*4;
+  else if (pc[4] == 0x34190000 || pc[4] == 0x34190002)
+    {
+      pc += 4;
+      off = 10 * 4;
+    }
+  else if (pc[5] == 0x34190000 || pc[5] == 0x34190002)
+    {
+      pc += 5;
+      off = 10 * 4;
+    }
+  else
+    {
+      /* We may have to unwind through an alternate signal stack.
+	 We assume that the alignment of the alternate signal stack
+	 is BIGGEST_ALIGNMENT (i.e., that it has been allocated using
+	 malloc).  As a result, we can't distinguish trampolines
+	 used prior to 2.6.5-rc2-pa4.  However after 2.6.5-rc2-pa4,
+	 the return address of a signal trampoline will be on an odd
+	 word boundary and we can then determine the frame offset.  */
+      sp = (unsigned long)context->ra;
+      pc = (unsigned int *)sp;
+      if ((pc[0] == 0x34190000 || pc[0] == 0x34190002) && (sp & 4))
+	off = 5 * 4;
+      else
+	return _URC_END_OF_STACK;
+    }
+
+  if (pc[1] != 0x3414015a
+      || pc[2] != 0xe4008200
+      || pc[3] != 0x08000240)
+    return _URC_END_OF_STACK;
+
+  frame = (struct rt_sigframe *)(sp + off);
+  sc = &frame->uc.uc_mcontext;
+
+  new_cfa = sc->sc_gr[30];
+  fs->regs.cfa_how = CFA_REG_OFFSET;
+  fs->regs.cfa_reg = 30;
+  fs->regs.cfa_offset = new_cfa - (long) context->cfa;
+  for (i = 1; i <= 31; i++)
+    {
+      fs->regs.reg[i].how = REG_SAVED_OFFSET;
+      fs->regs.reg[i].loc.offset = (long)&sc->sc_gr[i] - new_cfa;
+    }
+  for (i = 4; i <= 31; i++)
+    {
+      /* FP regs have left and right halves */
+      fs->regs.reg[2*i+24].how = REG_SAVED_OFFSET;
+      fs->regs.reg[2*i+24].loc.offset
+	= (long)&sc->sc_fr[i] - new_cfa;
+      fs->regs.reg[2*i+24+1].how = REG_SAVED_OFFSET;
+      fs->regs.reg[2*i+24+1].loc.offset
+	= (long)&sc->sc_fr[i] + 4 - new_cfa;
+    }
+  fs->regs.reg[88].how = REG_SAVED_OFFSET;
+  fs->regs.reg[88].loc.offset = (long) &sc->sc_sar - new_cfa;
+  fs->regs.reg[DWARF_ALT_FRAME_RETURN_COLUMN].how = REG_SAVED_OFFSET;
+  fs->regs.reg[DWARF_ALT_FRAME_RETURN_COLUMN].loc.offset
+    = (long) &sc->sc_iaoq[0] - new_cfa;
+  fs->retaddr_column = DWARF_ALT_FRAME_RETURN_COLUMN;
+  return _URC_NO_REASON;
+}
+#endif /* inhibit_libc */