105 lines
3.3 KiB
C
105 lines
3.3 KiB
C
/* DWARF2 EH unwinding support for Alpha Linux.
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Copyright (C) 2004-2021 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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GCC is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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Under Section 7 of GPL version 3, you are granted additional
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permissions described in the GCC Runtime Library Exception, version
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3.1, as published by the Free Software Foundation.
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You should have received a copy of the GNU General Public License and
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a copy of the GCC Runtime Library Exception along with this program;
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see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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<http://www.gnu.org/licenses/>. */
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#ifndef inhibit_libc
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/* Do code reading to identify a signal frame, and set the frame
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state data appropriately. See unwind-dw2.c for the structs. */
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#include <signal.h>
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#include <sys/ucontext.h>
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#define MD_FALLBACK_FRAME_STATE_FOR alpha_fallback_frame_state
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static _Unwind_Reason_Code
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alpha_fallback_frame_state (struct _Unwind_Context *context,
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_Unwind_FrameState *fs)
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{
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unsigned int *pc = context->ra;
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struct sigcontext *sc;
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long new_cfa;
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int i;
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if (pc[0] != 0x47fe0410 /* mov $30,$16 */
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|| pc[2] != 0x00000083) /* callsys */
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return _URC_END_OF_STACK;
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if (context->cfa == 0)
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return _URC_END_OF_STACK;
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if (pc[1] == 0x201f0067) /* lda $0,NR_sigreturn */
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sc = context->cfa;
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else if (pc[1] == 0x201f015f) /* lda $0,NR_rt_sigreturn */
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{
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struct rt_sigframe {
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siginfo_t info;
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ucontext_t uc;
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} *rt_ = context->cfa;
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/* The void * cast is necessary to avoid an aliasing warning.
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The aliasing warning is correct, but should not be a problem
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because it does not alias anything. */
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sc = (struct sigcontext *) (void *) &rt_->uc.uc_mcontext;
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}
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else
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return _URC_END_OF_STACK;
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new_cfa = sc->sc_regs[30];
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fs->regs.cfa_how = CFA_REG_OFFSET;
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fs->regs.cfa_reg = 30;
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fs->regs.cfa_offset = new_cfa - (long) context->cfa;
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for (i = 0; i < 30; ++i)
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{
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fs->regs.reg[i].how = REG_SAVED_OFFSET;
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fs->regs.reg[i].loc.offset
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= (long) &sc->sc_regs[i] - new_cfa;
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}
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for (i = 0; i < 31; ++i)
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{
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fs->regs.reg[i+32].how = REG_SAVED_OFFSET;
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fs->regs.reg[i+32].loc.offset
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= (long) &sc->sc_fpregs[i] - new_cfa;
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}
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fs->regs.reg[64].how = REG_SAVED_OFFSET;
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fs->regs.reg[64].loc.offset = (long)&sc->sc_pc - new_cfa;
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fs->retaddr_column = 64;
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fs->signal_frame = 1;
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return _URC_NO_REASON;
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}
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#define MD_FROB_UPDATE_CONTEXT alpha_frob_update_context
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/* Fix up for signal handlers that don't have S flag set. */
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static void
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alpha_frob_update_context (struct _Unwind_Context *context,
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_Unwind_FrameState *fs ATTRIBUTE_UNUSED)
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{
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unsigned int *pc = context->ra;
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if (pc[0] == 0x47fe0410 /* mov $30,$16 */
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&& pc[2] == 0x00000083 /* callsys */
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&& (pc[1] == 0x201f0067 /* lda $0,NR_sigreturn */
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|| pc[1] == 0x201f015f)) /* lda $0,NR_rt_sigreturn */
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_Unwind_SetSignalFrame (context, 1);
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}
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#endif
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