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authorobrien <obrien@FreeBSD.org>1999-08-26 09:30:50 +0000
committerobrien <obrien@FreeBSD.org>1999-08-26 09:30:50 +0000
commit0bedf4fb30066e5e1d4342a1d3914dae7d37cba7 (patch)
tree68d8110b41afd0ebbf39167b1a4918eea667a7c5 /contrib/gcc/frame.c
parentd4db5fb866b7ad5216abd5047774a3973b9901a9 (diff)
downloadFreeBSD-src-0bedf4fb30066e5e1d4342a1d3914dae7d37cba7.zip
FreeBSD-src-0bedf4fb30066e5e1d4342a1d3914dae7d37cba7.tar.gz
Virgin import of gcc from EGCS 1.1.2
Diffstat (limited to 'contrib/gcc/frame.c')
-rw-r--r--contrib/gcc/frame.c815
1 files changed, 815 insertions, 0 deletions
diff --git a/contrib/gcc/frame.c b/contrib/gcc/frame.c
new file mode 100644
index 0000000..4b62759
--- /dev/null
+++ b/contrib/gcc/frame.c
@@ -0,0 +1,815 @@
+/* Subroutines needed for unwinding stack frames for exception handling. */
+/* Compile this one with gcc. */
+/* Copyright (C) 1997 Free Software Foundation, Inc.
+ Contributed by Jason Merrill <jason@cygnus.com>.
+
+This file is part of GNU CC.
+
+GNU CC 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.
+
+GNU CC 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 GNU CC; see the file COPYING. If not, write to
+the Free Software Foundation, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
+
+/* As a special exception, if you link this library with other files,
+ some of which are compiled with GCC, to produce an executable,
+ this library does not by itself cause the resulting executable
+ to be covered by the GNU General Public License.
+ This exception does not however invalidate any other reasons why
+ the executable file might be covered by the GNU General Public License. */
+
+/* It is incorrect to include config.h here, because this file is being
+ compiled for the target, and hence definitions concerning only the host
+ do not apply. */
+
+#include "tconfig.h"
+
+/* We disable this when inhibit_libc, so that gcc can still be built without
+ needing header files first. */
+/* ??? This is not a good solution, since prototypes may be required in
+ some cases for correct code. See also libgcc2.c. */
+#ifndef inhibit_libc
+/* fixproto guarantees these system headers exist. */
+#include <stdlib.h>
+#include <unistd.h>
+#endif
+
+#include "defaults.h"
+
+#ifdef DWARF2_UNWIND_INFO
+#include "gansidecl.h"
+#include "dwarf2.h"
+#include <stddef.h>
+#include "frame.h"
+#include "gthr.h"
+
+#ifdef __GTHREAD_MUTEX_INIT
+static __gthread_mutex_t object_mutex = __GTHREAD_MUTEX_INIT;
+#else
+static __gthread_mutex_t object_mutex;
+#endif
+
+/* Don't use `fancy_abort' here even if config.h says to use it. */
+#ifdef abort
+#undef abort
+#endif
+
+/* Some types used by the DWARF 2 spec. */
+
+typedef int sword __attribute__ ((mode (SI)));
+typedef unsigned int uword __attribute__ ((mode (SI)));
+typedef unsigned int uaddr __attribute__ ((mode (pointer)));
+typedef int saddr __attribute__ ((mode (pointer)));
+typedef unsigned char ubyte;
+
+/* The first few fields of a CIE. The CIE_id field is 0 for a CIE,
+ to distinguish it from a valid FDE. FDEs are aligned to an addressing
+ unit boundary, but the fields within are unaligned. */
+
+struct dwarf_cie {
+ uword length;
+ sword CIE_id;
+ ubyte version;
+ char augmentation[0];
+} __attribute__ ((packed, aligned (__alignof__ (void *))));
+
+/* The first few fields of an FDE. */
+
+struct dwarf_fde {
+ uword length;
+ sword CIE_delta;
+ void* pc_begin;
+ uaddr pc_range;
+} __attribute__ ((packed, aligned (__alignof__ (void *))));
+
+typedef struct dwarf_fde fde;
+
+/* Objects to be searched for frame unwind info. */
+
+static struct object *objects;
+
+/* The information we care about from a CIE. */
+
+struct cie_info {
+ char *augmentation;
+ void *eh_ptr;
+ int code_align;
+ int data_align;
+ unsigned ra_regno;
+};
+
+/* The current unwind state, plus a saved copy for DW_CFA_remember_state. */
+
+struct frame_state_internal
+{
+ struct frame_state s;
+ struct frame_state_internal *saved_state;
+};
+
+/* Decode the unsigned LEB128 constant at BUF into the variable pointed to
+ by R, and return the new value of BUF. */
+
+static void *
+decode_uleb128 (unsigned char *buf, unsigned *r)
+{
+ unsigned shift = 0;
+ unsigned result = 0;
+
+ while (1)
+ {
+ unsigned byte = *buf++;
+ result |= (byte & 0x7f) << shift;
+ if ((byte & 0x80) == 0)
+ break;
+ shift += 7;
+ }
+ *r = result;
+ return buf;
+}
+
+/* Decode the signed LEB128 constant at BUF into the variable pointed to
+ by R, and return the new value of BUF. */
+
+static void *
+decode_sleb128 (unsigned char *buf, int *r)
+{
+ unsigned shift = 0;
+ unsigned result = 0;
+ unsigned byte;
+
+ while (1)
+ {
+ byte = *buf++;
+ result |= (byte & 0x7f) << shift;
+ shift += 7;
+ if ((byte & 0x80) == 0)
+ break;
+ }
+ if (shift < (sizeof (*r) * 8) && (byte & 0x40) != 0)
+ result |= - (1 << shift);
+
+ *r = result;
+ return buf;
+}
+
+/* Read unaligned data from the instruction buffer. */
+
+union unaligned {
+ void *p;
+ unsigned b2 __attribute__ ((mode (HI)));
+ unsigned b4 __attribute__ ((mode (SI)));
+ unsigned b8 __attribute__ ((mode (DI)));
+} __attribute__ ((packed));
+static inline void *
+read_pointer (void *p)
+{ union unaligned *up = p; return up->p; }
+static inline unsigned
+read_1byte (void *p)
+{ return *(unsigned char *)p; }
+static inline unsigned
+read_2byte (void *p)
+{ union unaligned *up = p; return up->b2; }
+static inline unsigned
+read_4byte (void *p)
+{ union unaligned *up = p; return up->b4; }
+static inline unsigned long
+read_8byte (void *p)
+{ union unaligned *up = p; return up->b8; }
+
+/* Ordering function for FDEs. Functions can't overlap, so we just compare
+ their starting addresses. */
+
+static inline saddr
+fde_compare (fde *x, fde *y)
+{
+ return (saddr)x->pc_begin - (saddr)y->pc_begin;
+}
+
+/* Return the address of the FDE after P. */
+
+static inline fde *
+next_fde (fde *p)
+{
+ return (fde *)(((char *)p) + p->length + sizeof (p->length));
+}
+
+/* Sorting an array of FDEs by address.
+ (Ideally we would have the linker sort the FDEs so we don't have to do
+ it at run time. But the linkers are not yet prepared for this.) */
+
+/* This is a special mix of insertion sort and heap sort, optimized for
+ the data sets that actually occur. They look like
+ 101 102 103 127 128 105 108 110 190 111 115 119 125 160 126 129 130.
+ I.e. a linearly increasing sequence (coming from functions in the text
+ section), with additionally a few unordered elements (coming from functions
+ in gnu_linkonce sections) whose values are higher than the values in the
+ surrounding linear sequence (but not necessarily higher than the values
+ at the end of the linear sequence!).
+ The worst-case total run time is O(N) + O(n log (n)), where N is the
+ total number of FDEs and n is the number of erratic ones. */
+
+typedef struct fde_vector
+{
+ fde **array;
+ size_t count;
+} fde_vector;
+
+typedef struct fde_accumulator
+{
+ fde_vector linear;
+ fde_vector erratic;
+} fde_accumulator;
+
+static inline void
+start_fde_sort (fde_accumulator *accu, size_t count)
+{
+ accu->linear.array = (fde **) malloc (sizeof (fde *) * count);
+ accu->erratic.array = (fde **) malloc (sizeof (fde *) * count);
+ accu->linear.count = 0;
+ accu->erratic.count = 0;
+}
+
+static inline void
+fde_insert (fde_accumulator *accu, fde *this_fde)
+{
+ accu->linear.array[accu->linear.count++] = this_fde;
+}
+
+/* Split LINEAR into a linear sequence with low values and an erratic
+ sequence with high values, put the linear one (of longest possible
+ length) into LINEAR and the erratic one into ERRATIC. This is O(N). */
+static inline void
+fde_split (fde_vector *linear, fde_vector *erratic)
+{
+ size_t count = linear->count;
+ size_t linear_max = (size_t) -1;
+ size_t previous_max[count];
+ size_t i, j;
+
+ for (i = 0; i < count; i++)
+ {
+ for (j = linear_max;
+ j != (size_t) -1
+ && fde_compare (linear->array[i], linear->array[j]) < 0;
+ j = previous_max[j])
+ {
+ erratic->array[erratic->count++] = linear->array[j];
+ linear->array[j] = (fde *) NULL;
+ }
+ previous_max[i] = j;
+ linear_max = i;
+ }
+
+ for (i = 0, j = 0; i < count; i++)
+ if (linear->array[i] != (fde *) NULL)
+ linear->array[j++] = linear->array[i];
+ linear->count = j;
+}
+
+/* This is O(n log(n)). BSD/OS defines heapsort in stdlib.h, so we must
+ use a name that does not conflict. */
+static inline void
+frame_heapsort (fde_vector *erratic)
+{
+ /* For a description of this algorithm, see:
+ Samuel P. Harbison, Guy L. Steele Jr.: C, a reference manual, 2nd ed.,
+ p. 60-61. */
+ fde ** a = erratic->array;
+ /* A portion of the array is called a "heap" if for all i>=0:
+ If i and 2i+1 are valid indices, then a[i] >= a[2i+1].
+ If i and 2i+2 are valid indices, then a[i] >= a[2i+2]. */
+#define SWAP(x,y) do { fde * tmp = x; x = y; y = tmp; } while (0)
+ size_t n = erratic->count;
+ size_t m = n;
+ size_t i;
+
+ while (m > 0)
+ {
+ /* Invariant: a[m..n-1] is a heap. */
+ m--;
+ for (i = m; 2*i+1 < n; )
+ {
+ if (2*i+2 < n
+ && fde_compare (a[2*i+2], a[2*i+1]) > 0
+ && fde_compare (a[2*i+2], a[i]) > 0)
+ {
+ SWAP (a[i], a[2*i+2]);
+ i = 2*i+2;
+ }
+ else if (fde_compare (a[2*i+1], a[i]) > 0)
+ {
+ SWAP (a[i], a[2*i+1]);
+ i = 2*i+1;
+ }
+ else
+ break;
+ }
+ }
+ while (n > 1)
+ {
+ /* Invariant: a[0..n-1] is a heap. */
+ n--;
+ SWAP (a[0], a[n]);
+ for (i = 0; 2*i+1 < n; )
+ {
+ if (2*i+2 < n
+ && fde_compare (a[2*i+2], a[2*i+1]) > 0
+ && fde_compare (a[2*i+2], a[i]) > 0)
+ {
+ SWAP (a[i], a[2*i+2]);
+ i = 2*i+2;
+ }
+ else if (fde_compare (a[2*i+1], a[i]) > 0)
+ {
+ SWAP (a[i], a[2*i+1]);
+ i = 2*i+1;
+ }
+ else
+ break;
+ }
+ }
+#undef SWAP
+}
+
+/* Merge V1 and V2, both sorted, and put the result into V1. */
+static void
+fde_merge (fde_vector *v1, const fde_vector *v2)
+{
+ size_t i1, i2;
+ fde * fde2;
+
+ i2 = v2->count;
+ if (i2 > 0)
+ {
+ i1 = v1->count;
+ do {
+ i2--;
+ fde2 = v2->array[i2];
+ while (i1 > 0 && fde_compare (v1->array[i1-1], fde2) > 0)
+ {
+ v1->array[i1+i2] = v1->array[i1-1];
+ i1--;
+ }
+ v1->array[i1+i2] = fde2;
+ } while (i2 > 0);
+ v1->count += v2->count;
+ }
+}
+
+static fde **
+end_fde_sort (fde_accumulator *accu, size_t count)
+{
+ if (accu->linear.count != count)
+ abort ();
+ fde_split (&accu->linear, &accu->erratic);
+ if (accu->linear.count + accu->erratic.count != count)
+ abort ();
+ frame_heapsort (&accu->erratic);
+ fde_merge (&accu->linear, &accu->erratic);
+ free (accu->erratic.array);
+ return accu->linear.array;
+}
+
+static size_t
+count_fdes (fde *this_fde)
+{
+ size_t count;
+
+ for (count = 0; this_fde->length != 0; this_fde = next_fde (this_fde))
+ {
+ /* Skip CIEs and linked once FDE entries. */
+ if (this_fde->CIE_delta == 0 || this_fde->pc_begin == 0)
+ continue;
+
+ ++count;
+ }
+
+ return count;
+}
+
+static void
+add_fdes (fde *this_fde, fde_accumulator *accu, void **beg_ptr, void **end_ptr)
+{
+ void *pc_begin = *beg_ptr;
+ void *pc_end = *end_ptr;
+
+ for (; this_fde->length != 0; this_fde = next_fde (this_fde))
+ {
+ /* Skip CIEs and linked once FDE entries. */
+ if (this_fde->CIE_delta == 0 || this_fde->pc_begin == 0)
+ continue;
+
+ fde_insert (accu, this_fde);
+
+ if (this_fde->pc_begin < pc_begin)
+ pc_begin = this_fde->pc_begin;
+ if (this_fde->pc_begin + this_fde->pc_range > pc_end)
+ pc_end = this_fde->pc_begin + this_fde->pc_range;
+ }
+
+ *beg_ptr = pc_begin;
+ *end_ptr = pc_end;
+}
+
+/* Set up a sorted array of pointers to FDEs for a loaded object. We
+ count up the entries before allocating the array because it's likely to
+ be faster. */
+
+static void
+frame_init (struct object* ob)
+{
+ size_t count;
+ fde_accumulator accu;
+ void *pc_begin, *pc_end;
+
+ if (ob->fde_array)
+ {
+ fde **p = ob->fde_array;
+ for (count = 0; *p; ++p)
+ count += count_fdes (*p);
+ }
+ else
+ count = count_fdes (ob->fde_begin);
+
+ ob->count = count;
+
+ start_fde_sort (&accu, count);
+ pc_begin = (void*)(uaddr)-1;
+ pc_end = 0;
+
+ if (ob->fde_array)
+ {
+ fde **p = ob->fde_array;
+ for (; *p; ++p)
+ add_fdes (*p, &accu, &pc_begin, &pc_end);
+ }
+ else
+ add_fdes (ob->fde_begin, &accu, &pc_begin, &pc_end);
+
+ ob->fde_array = end_fde_sort (&accu, count);
+ ob->pc_begin = pc_begin;
+ ob->pc_end = pc_end;
+}
+
+/* Return a pointer to the FDE for the function containing PC. */
+
+static fde *
+find_fde (void *pc)
+{
+ struct object *ob;
+ size_t lo, hi;
+
+ __gthread_mutex_lock (&object_mutex);
+
+ for (ob = objects; ob; ob = ob->next)
+ {
+ if (ob->pc_begin == 0)
+ frame_init (ob);
+ if (pc >= ob->pc_begin && pc < ob->pc_end)
+ break;
+ }
+
+ __gthread_mutex_unlock (&object_mutex);
+
+ if (ob == 0)
+ return 0;
+
+ /* Standard binary search algorithm. */
+ for (lo = 0, hi = ob->count; lo < hi; )
+ {
+ size_t i = (lo + hi) / 2;
+ fde *f = ob->fde_array[i];
+
+ if (pc < f->pc_begin)
+ hi = i;
+ else if (pc >= f->pc_begin + f->pc_range)
+ lo = i + 1;
+ else
+ return f;
+ }
+
+ return 0;
+}
+
+static inline struct dwarf_cie *
+get_cie (fde *f)
+{
+ return ((void *)&f->CIE_delta) - f->CIE_delta;
+}
+
+/* Extract any interesting information from the CIE for the translation
+ unit F belongs to. */
+
+static void *
+extract_cie_info (fde *f, struct cie_info *c)
+{
+ void *p;
+ int i;
+
+ c->augmentation = get_cie (f)->augmentation;
+
+ if (strcmp (c->augmentation, "") != 0
+ && strcmp (c->augmentation, "eh") != 0
+ && c->augmentation[0] != 'z')
+ return 0;
+
+ p = c->augmentation + strlen (c->augmentation) + 1;
+
+ if (strcmp (c->augmentation, "eh") == 0)
+ {
+ c->eh_ptr = read_pointer (p);
+ p += sizeof (void *);
+ }
+ else
+ c->eh_ptr = 0;
+
+ p = decode_uleb128 (p, &c->code_align);
+ p = decode_sleb128 (p, &c->data_align);
+ c->ra_regno = *(unsigned char *)p++;
+
+ /* If the augmentation starts with 'z', we now see the length of the
+ augmentation fields. */
+ if (c->augmentation[0] == 'z')
+ {
+ p = decode_uleb128 (p, &i);
+ p += i;
+ }
+
+ return p;
+}
+
+/* Decode one instruction's worth of DWARF 2 call frame information.
+ Used by __frame_state_for. Takes pointers P to the instruction to
+ decode, STATE to the current register unwind information, INFO to the
+ current CIE information, and PC to the current PC value. Returns a
+ pointer to the next instruction. */
+
+static void *
+execute_cfa_insn (void *p, struct frame_state_internal *state,
+ struct cie_info *info, void **pc)
+{
+ unsigned insn = *(unsigned char *)p++;
+ unsigned reg;
+ int offset;
+
+ if (insn & DW_CFA_advance_loc)
+ *pc += ((insn & 0x3f) * info->code_align);
+ else if (insn & DW_CFA_offset)
+ {
+ reg = (insn & 0x3f);
+ p = decode_uleb128 (p, &offset);
+ offset *= info->data_align;
+ state->s.saved[reg] = REG_SAVED_OFFSET;
+ state->s.reg_or_offset[reg] = offset;
+ }
+ else if (insn & DW_CFA_restore)
+ {
+ reg = (insn & 0x3f);
+ state->s.saved[reg] = REG_UNSAVED;
+ }
+ else switch (insn)
+ {
+ case DW_CFA_set_loc:
+ *pc = read_pointer (p);
+ p += sizeof (void *);
+ break;
+ case DW_CFA_advance_loc1:
+ *pc += read_1byte (p);
+ p += 1;
+ break;
+ case DW_CFA_advance_loc2:
+ *pc += read_2byte (p);
+ p += 2;
+ break;
+ case DW_CFA_advance_loc4:
+ *pc += read_4byte (p);
+ p += 4;
+ break;
+
+ case DW_CFA_offset_extended:
+ p = decode_uleb128 (p, &reg);
+ p = decode_uleb128 (p, &offset);
+ offset *= info->data_align;
+ state->s.saved[reg] = REG_SAVED_OFFSET;
+ state->s.reg_or_offset[reg] = offset;
+ break;
+ case DW_CFA_restore_extended:
+ p = decode_uleb128 (p, &reg);
+ state->s.saved[reg] = REG_UNSAVED;
+ break;
+
+ case DW_CFA_undefined:
+ case DW_CFA_same_value:
+ case DW_CFA_nop:
+ break;
+
+ case DW_CFA_register:
+ {
+ unsigned reg2;
+ p = decode_uleb128 (p, &reg);
+ p = decode_uleb128 (p, &reg2);
+ state->s.saved[reg] = REG_SAVED_REG;
+ state->s.reg_or_offset[reg] = reg2;
+ }
+ break;
+
+ case DW_CFA_def_cfa:
+ p = decode_uleb128 (p, &reg);
+ p = decode_uleb128 (p, &offset);
+ state->s.cfa_reg = reg;
+ state->s.cfa_offset = offset;
+ break;
+ case DW_CFA_def_cfa_register:
+ p = decode_uleb128 (p, &reg);
+ state->s.cfa_reg = reg;
+ break;
+ case DW_CFA_def_cfa_offset:
+ p = decode_uleb128 (p, &offset);
+ state->s.cfa_offset = offset;
+ break;
+
+ case DW_CFA_remember_state:
+ {
+ struct frame_state_internal *save =
+ (struct frame_state_internal *)
+ malloc (sizeof (struct frame_state_internal));
+ memcpy (save, state, sizeof (struct frame_state_internal));
+ state->saved_state = save;
+ }
+ break;
+ case DW_CFA_restore_state:
+ {
+ struct frame_state_internal *save = state->saved_state;
+ memcpy (state, save, sizeof (struct frame_state_internal));
+ free (save);
+ }
+ break;
+
+ /* FIXME: Hardcoded for SPARC register window configuration. */
+ case DW_CFA_GNU_window_save:
+ for (reg = 16; reg < 32; ++reg)
+ {
+ state->s.saved[reg] = REG_SAVED_OFFSET;
+ state->s.reg_or_offset[reg] = (reg - 16) * sizeof (void *);
+ }
+ break;
+
+ case DW_CFA_GNU_args_size:
+ p = decode_uleb128 (p, &offset);
+ state->s.args_size = offset;
+ break;
+
+ default:
+ abort ();
+ }
+ return p;
+}
+
+/* Called from crtbegin.o to register the unwind info for an object. */
+
+void
+__register_frame_info (void *begin, struct object *ob)
+{
+ ob->fde_begin = begin;
+
+ ob->pc_begin = ob->pc_end = 0;
+ ob->fde_array = 0;
+ ob->count = 0;
+
+ __gthread_mutex_lock (&object_mutex);
+
+ ob->next = objects;
+ objects = ob;
+
+ __gthread_mutex_unlock (&object_mutex);
+}
+
+void
+__register_frame (void *begin)
+{
+ struct object *ob = (struct object *) malloc (sizeof (struct object));
+ __register_frame_info (begin, ob);
+}
+
+/* Similar, but BEGIN is actually a pointer to a table of unwind entries
+ for different translation units. Called from the file generated by
+ collect2. */
+
+void
+__register_frame_info_table (void *begin, struct object *ob)
+{
+ ob->fde_begin = begin;
+ ob->fde_array = begin;
+
+ ob->pc_begin = ob->pc_end = 0;
+ ob->count = 0;
+
+ __gthread_mutex_lock (&object_mutex);
+
+ ob->next = objects;
+ objects = ob;
+
+ __gthread_mutex_unlock (&object_mutex);
+}
+
+void
+__register_frame_table (void *begin)
+{
+ struct object *ob = (struct object *) malloc (sizeof (struct object));
+ __register_frame_info_table (begin, ob);
+}
+
+/* Called from crtbegin.o to deregister the unwind info for an object. */
+
+void *
+__deregister_frame_info (void *begin)
+{
+ struct object **p;
+
+ __gthread_mutex_lock (&object_mutex);
+
+ p = &objects;
+ while (*p)
+ {
+ if ((*p)->fde_begin == begin)
+ {
+ struct object *ob = *p;
+ *p = (*p)->next;
+
+ /* If we've run init_frame for this object, free the FDE array. */
+ if (ob->pc_begin)
+ free (ob->fde_array);
+
+ __gthread_mutex_unlock (&object_mutex);
+ return (void *) ob;
+ }
+ p = &((*p)->next);
+ }
+
+ __gthread_mutex_unlock (&object_mutex);
+ abort ();
+}
+
+void
+__deregister_frame (void *begin)
+{
+ free (__deregister_frame_info (begin));
+}
+
+/* Called from __throw to find the registers to restore for a given
+ PC_TARGET. The caller should allocate a local variable of `struct
+ frame_state' (declared in frame.h) and pass its address to STATE_IN. */
+
+struct frame_state *
+__frame_state_for (void *pc_target, struct frame_state *state_in)
+{
+ fde *f;
+ void *insn, *end, *pc;
+ struct cie_info info;
+ struct frame_state_internal state;
+
+ f = find_fde (pc_target);
+ if (f == 0)
+ return 0;
+
+ insn = extract_cie_info (f, &info);
+ if (insn == 0)
+ return 0;
+
+ memset (&state, 0, sizeof (state));
+ state.s.retaddr_column = info.ra_regno;
+ state.s.eh_ptr = info.eh_ptr;
+
+ /* First decode all the insns in the CIE. */
+ end = next_fde ((fde*) get_cie (f));
+ while (insn < end)
+ insn = execute_cfa_insn (insn, &state, &info, 0);
+
+ insn = ((fde *)f) + 1;
+
+ if (info.augmentation[0] == 'z')
+ {
+ int i;
+ insn = decode_uleb128 (insn, &i);
+ insn += i;
+ }
+
+ /* Then the insns in the FDE up to our target PC. */
+ end = next_fde (f);
+ pc = f->pc_begin;
+ while (insn < end && pc <= pc_target)
+ insn = execute_cfa_insn (insn, &state, &info, &pc);
+
+ memcpy (state_in, &state.s, sizeof (state.s));
+ return state_in;
+}
+#endif /* DWARF2_UNWIND_INFO */
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