From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/config/xtensa/linux-unwind.h | 97 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 gcc/config/xtensa/linux-unwind.h (limited to 'gcc/config/xtensa/linux-unwind.h') diff --git a/gcc/config/xtensa/linux-unwind.h b/gcc/config/xtensa/linux-unwind.h new file mode 100644 index 000000000..245649728 --- /dev/null +++ b/gcc/config/xtensa/linux-unwind.h @@ -0,0 +1,97 @@ +/* DWARF2 EH unwinding support for Xtensa. + Copyright (C) 2008, 2009, 2012 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 +. */ + +/* Do code reading to identify a signal frame, and set the frame + state data appropriately. See unwind-dw2-xtensa.c for the structs. + Don't use this at all if inhibit_libc is used. */ + +#ifndef inhibit_libc + +#include +#include + +/* Encoded bytes for Xtensa instructions: + movi a2, __NR_rt_sigreturn + syscall + entry (first byte only) + Some of the bytes are endian-dependent. */ + +#define MOVI_BYTE0 0x22 +#define MOVI_BYTE2 225 /* __NR_rt_sigreturn */ +#define SYSC_BYTE0 0 +#define SYSC_BYTE2 0 + +#ifdef __XTENSA_EB__ +#define MOVI_BYTE1 0x0a +#define SYSC_BYTE1 0x05 +#define ENTRY_BYTE 0x6c +#else +#define MOVI_BYTE1 0xa0 +#define SYSC_BYTE1 0x50 +#define ENTRY_BYTE 0x36 +#endif + +#define MD_FALLBACK_FRAME_STATE_FOR xtensa_fallback_frame_state + +static _Unwind_Reason_Code +xtensa_fallback_frame_state (struct _Unwind_Context *context, + _Unwind_FrameState *fs) +{ + unsigned char *pc = context->ra; + struct sigcontext *sc; + + struct rt_sigframe { + siginfo_t info; + struct ucontext uc; + } *rt_; + + /* movi a2, __NR_rt_sigreturn; syscall */ + if (pc[0] != MOVI_BYTE0 + || pc[1] != MOVI_BYTE1 + || pc[2] != MOVI_BYTE2 + || pc[3] != SYSC_BYTE0 + || pc[4] != SYSC_BYTE1 + || pc[5] != SYSC_BYTE2) + return _URC_END_OF_STACK; + + rt_ = context->sp; + sc = &rt_->uc.uc_mcontext; + fs->signal_regs = (_Unwind_Word *) sc->sc_a; + + /* If the signal arrived just before an ENTRY instruction, find the return + address and pretend the signal arrived before executing the CALL. */ + if (*(unsigned char *) sc->sc_pc == ENTRY_BYTE) + { + unsigned callinc = (sc->sc_ps >> 16) & 3; + fs->signal_ra = ((sc->sc_a[callinc << 2] & XTENSA_RA_FIELD_MASK) + | context->ra_high_bits) - 3; + } + else + fs->signal_ra = sc->sc_pc; + + fs->signal_frame = 1; + return _URC_NO_REASON; +} + +#endif /* ifdef inhibit_libc */ -- cgit v1.2.3