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[m68k 08/13] unwind support for signal handler
- From: zippel at linux-m68k dot org
- To: gcc-patches at gcc dot gnu dot org
- Date: Tue, 30 Jan 2007 12:26:23 +0100
- Subject: [m68k 08/13] unwind support for signal handler
- References: <20070130112615.782382000@linux-m68k.org>
Hi,
This adds support for unwinding through linux signal trampolines.
2007-01-30 Roman Zippel <zippel@linux-m68k.org>
* config/m68k/linux.h (MD_UNWIND_SUPPORT): Define.
* config/m68k/linux-unwind.h: New file.
---
gcc/config/m68k/linux-unwind.h | 153 +++++++++++++++++++++++++++++++++++++++++
gcc/config/m68k/linux.h | 2
2 files changed, 155 insertions(+)
Index: egcs/gcc/config/m68k/linux-unwind.h
===================================================================
--- /dev/null
+++ egcs/gcc/config/m68k/linux-unwind.h
@@ -0,0 +1,153 @@
+/* DWARF2 EH unwinding support for Linux/m68k.
+ Copyright (C) 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. */
+
+/* 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 at all if inhibit_libc is used. */
+
+#ifndef inhibit_libc
+
+#include <signal.h>
+
+/* <sys/ucontext.h> is unfortunaly broken right now */
+struct uw_ucontext {
+ unsigned long uc_flags;
+ struct ucontext *uc_link;
+ stack_t uc_stack;
+ mcontext_t uc_mcontext;
+ unsigned long uc_filler[80];
+ __sigset_t uc_sigmask;
+};
+
+#define MD_FALLBACK_FRAME_STATE_FOR m68k_fallback_frame_state
+
+#ifdef __mcoldfire__
+#define M68K_FP_SIZE 8
+#else
+#define M68K_FP_SIZE 12
+#endif
+
+static _Unwind_Reason_Code
+m68k_fallback_frame_state (struct _Unwind_Context *context,
+ _Unwind_FrameState *fs)
+{
+ unsigned short *pc = context->ra;
+ long cfa;
+
+ /* moveq #__NR_sigreturn,%d0; trap #0 */
+ if (pc[0] == 0x7077 && pc[1] == 0x4e40)
+ {
+ struct sigcontext *sc;
+
+ /* Context is passed as the 3rd argument. */
+ sc = *(struct sigcontext **) (context->cfa + 8);
+
+ cfa = sc->sc_usp;
+ fs->regs.cfa_how = CFA_REG_OFFSET;
+ fs->regs.cfa_reg = 15;
+ fs->regs.cfa_offset = cfa - (long) context->cfa;
+
+ fs->regs.reg[0].how = REG_SAVED_OFFSET;
+ fs->regs.reg[0].loc.offset = (long) &sc->sc_d0 - cfa;
+ fs->regs.reg[1].how = REG_SAVED_OFFSET;
+ fs->regs.reg[1].loc.offset = (long) &sc->sc_d1 - cfa;
+ fs->regs.reg[8].how = REG_SAVED_OFFSET;
+ fs->regs.reg[8].loc.offset = (long) &sc->sc_a0 - cfa;
+ fs->regs.reg[9].how = REG_SAVED_OFFSET;
+ fs->regs.reg[9].loc.offset = (long) &sc->sc_a1 - cfa;
+
+ fs->regs.reg[24].how = REG_SAVED_OFFSET;
+ fs->regs.reg[24].loc.offset = (long) &sc->sc_pc - cfa;
+
+ if (*(int *) sc->sc_fpstate)
+ {
+ int *fpregs = (int *) sc->sc_fpregs;
+
+ fs->regs.reg[16].how = REG_SAVED_OFFSET;
+ fs->regs.reg[16].loc.offset = (long) &fpregs[0] - cfa;
+ fs->regs.reg[17].how = REG_SAVED_OFFSET;
+ fs->regs.reg[17].loc.offset = (long) &fpregs[M68K_FP_SIZE/4] - cfa;
+ }
+ }
+#ifdef __mcoldfire__
+ /* move.l #__NR_rt_sigreturn,%d0; trap #0 */
+ else if (pc[0] == 0x203c && pc[1] == 0x0000 &&
+ pc[2] == 0x00ad && pc[3] == 0x4e40)
+#else
+ /* moveq #~__NR_rt_sigreturn,%d0; not.b %d0; trap #0 */
+ else if (pc[0] == 0x7052 && pc[1] == 0x4600 && pc[2] == 0x4e40)
+#endif
+ {
+ struct uw_ucontext *uc;
+ greg_t *gregs;
+ int i;
+
+ /* Context is passed as the 3rd argument. */
+ uc = *(struct uw_ucontext **) (context->cfa + 8);
+
+ gregs = uc->uc_mcontext.gregs;
+ cfa = gregs[15];
+ fs->regs.cfa_how = CFA_REG_OFFSET;
+ fs->regs.cfa_reg = 15;
+ fs->regs.cfa_offset = cfa - (long) context->cfa;
+
+ /* register %d0-%d7/%a0-%a6 */
+ for (i = 0; i <= 14; i++)
+ {
+ fs->regs.reg[i].how = REG_SAVED_OFFSET;
+ fs->regs.reg[i].loc.offset = (long) &gregs[i] - cfa;
+ }
+
+ /* return address */
+ fs->regs.reg[24].how = REG_SAVED_OFFSET;
+ fs->regs.reg[24].loc.offset = (long) &gregs[16] - cfa;
+
+#define uc_fpstate uc_filler[0]
+
+ if (uc->uc_fpstate)
+ {
+ long fpregs = (long) uc->uc_mcontext.fpregs.f_fpregs;
+
+ /* register %fp0-%fp7 */
+ for (i = 16; i <= 23; i++)
+ {
+ fs->regs.reg[i].how = REG_SAVED_OFFSET;
+ fs->regs.reg[i].loc.offset = fpregs - cfa;
+ fpregs += M68K_FP_SIZE;
+ }
+ }
+ }
+ else
+ return _URC_END_OF_STACK;
+
+ fs->retaddr_column = 24;
+ fs->signal_frame = 1;
+
+ return _URC_NO_REASON;
+}
+#endif /* ifdef inhibit_libc */
Index: egcs/gcc/config/m68k/linux.h
===================================================================
--- egcs.orig/gcc/config/m68k/linux.h
+++ egcs/gcc/config/m68k/linux.h
@@ -229,3 +229,5 @@ Boston, MA 02110-1301, USA. */
}
#define TARGET_ASM_FILE_END file_end_indicate_exec_stack
+
+#define MD_UNWIND_SUPPORT "config/m68k/linux-unwind.h"
--