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-rw-r--r--gas/dw2gencfi.c721
1 files changed, 721 insertions, 0 deletions
diff --git a/gas/dw2gencfi.c b/gas/dw2gencfi.c
new file mode 100644
index 00000000000..f83610b3765
--- /dev/null
+++ b/gas/dw2gencfi.c
@@ -0,0 +1,721 @@
+/* dw2gencfi.c - Support for generating Dwarf2 CFI information.
+ Copyright 2003 Free Software Foundation, Inc.
+ Contributed by Michal Ludvig <mludvig@suse.cz>
+
+ This file is part of GAS, the GNU Assembler.
+
+ GAS 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.
+
+ GAS 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 GAS; see the file COPYING. If not, write to the Free
+ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+ 02111-1307, USA. */
+
+#include <errno.h>
+#include "as.h"
+#include "dw2gencfi.h"
+
+/* Current target config. */
+static struct cfi_config current_config;
+
+/* This is the main entry point to the CFI machinery. */
+static void dot_cfi (int arg);
+
+const pseudo_typeS cfi_pseudo_table[] =
+ {
+ { "cfi_verbose", dot_cfi, CFI_verbose },
+ { "cfi_startproc", dot_cfi, CFI_startproc },
+ { "cfi_endproc", dot_cfi, CFI_endproc },
+ { "cfi_def_cfa", dot_cfi, CFA_def_cfa },
+ { "cfi_def_cfa_register", dot_cfi, CFA_def_cfa_register },
+ { "cfi_def_cfa_offset", dot_cfi, CFA_def_cfa_offset },
+ { "cfi_adjust_cfa_offset", dot_cfi, CFI_adjust_cfa_offset },
+ { "cfi_offset", dot_cfi, CFA_offset },
+ { NULL, NULL, 0 }
+ };
+
+static const char *
+cfi_insn_str (enum cfi_insn insn)
+{
+ switch (insn)
+ {
+ case CFA_nop:
+ return "CFA_nop";
+ case CFA_set_loc:
+ return "CFA_set_loc";
+ case CFA_advance_loc1:
+ return "CFA_advance_loc1";
+ case CFA_advance_loc2:
+ return "CFA_advance_loc2";
+ case CFA_advance_loc4:
+ return "CFA_advance_loc4";
+ case CFA_offset_extended:
+ return "CFA_offset_extended";
+ case CFA_resotre_extended:
+ return "CFA_resotre_extended";
+ case CFA_undefined:
+ return "CFA_undefined";
+ case CFA_same_value:
+ return "CFA_same_value";
+ case CFA_register:
+ return "CFA_register";
+ case CFA_remember_state:
+ return "CFA_remember_state";
+ case CFA_restore_state:
+ return "CFA_restore_state";
+ case CFA_def_cfa:
+ return "CFA_def_cfa";
+ case CFA_def_cfa_register:
+ return "CFA_def_cfa_register";
+ case CFA_def_cfa_offset:
+ return "CFA_def_cfa_offset";
+ case CFA_advance_loc:
+ return "CFA_advance_loc";
+ case CFA_offset:
+ return "CFA_offset";
+ case CFA_restore:
+ return "CFA_restore";
+ default:
+ break;
+ }
+
+ return "CFA_unknown";
+}
+
+struct cfi_data
+{
+ enum cfi_insn insn;
+ long param[2];
+ struct cfi_data *next;
+};
+
+struct cfi_info
+{
+ addressT start_address;
+ addressT end_address;
+ addressT last_address;
+ const char *labelname;
+ struct cfi_data *data;
+ struct cfi_info *next;
+};
+
+static struct cfi_info *cfi_info;
+
+static struct cfi_data *
+alloc_cfi_data (void)
+{
+ return (struct cfi_data *) xcalloc (sizeof (struct cfi_info), 1);
+}
+
+static struct cfi_info *
+alloc_cfi_info (void)
+{
+ return (struct cfi_info *) xcalloc (sizeof (struct cfi_info), 1);
+}
+
+/* Parse arguments. */
+static int
+cfi_parse_arg (long *param, int resolvereg)
+{
+ char *name, c, *p;
+ long value;
+ int retval = -1;
+ int nchars;
+
+ assert (param != NULL);
+ SKIP_WHITESPACE ();
+
+ if (sscanf (input_line_pointer, "%li%n", &value, &nchars) >= 1)
+ {
+ input_line_pointer += nchars;
+ retval = 1;
+ }
+ else if (resolvereg && (is_name_beginner (*input_line_pointer)))
+ {
+ name = input_line_pointer;
+ c = get_symbol_end ();
+ p = input_line_pointer;
+
+ if ((value = tc_regname_to_dw2regnum (name)) >= 0)
+ retval = 1;
+
+ *p = c;
+ }
+ else
+ as_bad (resolvereg ?
+ _("can't convert argument to a register number") :
+ _("can't convert argument to an integer"));
+
+ if (retval > 0)
+ *param = value;
+
+ SKIP_WHITESPACE ();
+ if (*input_line_pointer == ',')
+ {
+ input_line_pointer++;
+ SKIP_WHITESPACE ();
+ }
+
+ return retval;
+}
+
+static int
+cfi_parse_reg (long *param)
+{
+ return cfi_parse_arg (param, 1);
+}
+
+static int
+cfi_parse_const (long *param)
+{
+ return cfi_parse_arg (param, 0);
+}
+
+void
+cfi_add_insn (enum cfi_insn insn, long param0, long param1)
+{
+ struct cfi_data *data_ptr;
+
+ if (!cfi_info->data)
+ {
+ cfi_info->data = alloc_cfi_data ();
+ data_ptr = cfi_info->data;
+ }
+ else
+ {
+ data_ptr = cfi_info->data;
+
+ while (data_ptr && data_ptr->next)
+ data_ptr = data_ptr->next;
+
+ data_ptr->next = alloc_cfi_data ();
+
+ data_ptr = data_ptr->next;
+ }
+
+ data_ptr->insn = insn;
+ data_ptr->param[0] = param0;
+ data_ptr->param[1] = param1;
+}
+
+static void
+cfi_advance_loc (void)
+{
+ addressT curr_address = frag_now_fix ();
+ if (cfi_info->last_address == curr_address)
+ return;
+ cfi_add_insn (CFA_advance_loc,
+ (long) (curr_address - cfi_info->last_address), 0);
+ cfi_info->last_address = curr_address;
+}
+
+static long
+get_current_offset (struct cfi_info *info)
+{
+ long current_offset = 0;
+ struct cfi_data *data = info->data;
+
+ current_offset = 0;
+ while (data)
+ {
+ if (data->insn == CFA_def_cfa)
+ current_offset = data->param[1];
+ else if (data->insn == CFA_def_cfa_offset)
+ current_offset = data->param[0];
+ data = data->next;
+ }
+
+ return current_offset;
+}
+
+static void
+cfi_make_insn (int arg)
+{
+ long param[2] = { 0, 0 };
+
+ if (!cfi_info)
+ {
+ as_bad (_("CFI instruction used without previous .cfi_startproc"));
+ return;
+ }
+
+ cfi_advance_loc ();
+
+ switch (arg)
+ {
+ /* Instructions that take two arguments (register, integer). */
+ case CFA_offset:
+ case CFA_def_cfa:
+ if (cfi_parse_reg (&param[0]) < 0)
+ {
+ as_bad (_("first argument to %s is not a register"),
+ cfi_insn_str (arg));
+ return;
+ }
+ if (cfi_parse_const (&param[1]) < 0)
+ {
+ as_bad (_("second argument to %s is not a number"),
+ cfi_insn_str (arg));
+ return;
+ }
+ break;
+
+ /* Instructions that take one register argument. */
+ case CFA_def_cfa_register:
+ if (cfi_parse_reg (&param[0]) < 0)
+ {
+ as_bad (_("argument to %s is not a register"), cfi_insn_str (arg));
+ return;
+ }
+ break;
+
+ /* Instructions that take one integer argument. */
+ case CFA_def_cfa_offset:
+ if (cfi_parse_const (&param[0]) < 0)
+ {
+ as_bad (_("argument to %s is not a number"), cfi_insn_str (arg));
+ return;
+ }
+ break;
+
+ /* Special handling for pseudo-instruction. */
+ case CFI_adjust_cfa_offset:
+ if (cfi_parse_const (&param[0]) < 0)
+ {
+ as_bad (_("argument to %s is not a number"),
+ ".cfi_adjust_cfa_offset");
+ return;
+ }
+ param[0] += get_current_offset (cfi_info);
+ arg = CFA_def_cfa_offset;
+ break;
+
+ default:
+ as_bad (_("unknown CFI instruction %d (%s)"), arg, cfi_insn_str (arg));
+ return;
+ }
+ cfi_add_insn (arg, param[0], param[1]);
+}
+
+static symbolS *
+cfi_get_label (void)
+{
+ char symname[40], *symbase=".Llbl_cfi";
+ symbolS *symbolP;
+ unsigned int i = 0;
+
+ snprintf (symname, sizeof (symname), "%s_0x%lx",
+ symbase, (long) frag_now_fix ());
+ while ((symbolP = symbol_find (symname)))
+ {
+ if ((S_GET_VALUE (symbolP) == frag_now_fix ())
+ && (S_GET_SEGMENT (symbolP) == now_seg))
+ {
+ return symbolP;
+ }
+ snprintf (symname, sizeof (symname), "%s_0x%lx_%u",
+ symbase, (long) frag_now_fix (), i++);
+ }
+ symbolP = (symbolS *) local_symbol_make (symname, now_seg,
+ (valueT) frag_now_fix (),
+ frag_now);
+ return symbolP;
+}
+
+static void
+dot_cfi_startproc (void)
+{
+ if (cfi_info)
+ {
+ as_bad (_("previous CFI entry not closed (missing .cfi_endproc)"));
+ return;
+ }
+
+ cfi_info = alloc_cfi_info ();
+
+ cfi_info->start_address = frag_now_fix ();
+ cfi_info->last_address = cfi_info->start_address;
+ cfi_info->labelname = S_GET_NAME (cfi_get_label ());
+
+#ifdef tc_cfi_frame_initial_instructions
+ tc_cfi_frame_initial_instructions ();
+#endif
+}
+
+#define cfi_is_advance_insn(insn) \
+ ((insn >= CFA_set_loc && insn <= CFA_advance_loc4) \
+ || insn == CFA_advance_loc)
+
+enum data_types
+ {
+ t_ascii = 0,
+ t_byte = 1,
+ t_half = 2,
+ t_long = 4,
+ t_quad = 8,
+ t_uleb128 = 0x10,
+ t_sleb128 = 0x11
+ };
+
+/* Output CFI instructions to the file. */
+
+static int
+output_data (char **p, unsigned long *size, enum data_types type, long value)
+{
+ char *ptr = *p;
+ unsigned int ret_size;
+
+ switch (type)
+ {
+ case t_byte:
+ ret_size = 1;
+ break;
+ case t_half:
+ ret_size = 2;
+ break;
+ case t_long:
+ ret_size = 4;
+ break;
+ case t_quad:
+ case t_uleb128:
+ case t_sleb128:
+ ret_size = 8;
+ break;
+ default:
+ as_warn (_("unknown type %d"), type);
+ return 0;
+ }
+
+ if (*size < ret_size)
+ {
+ as_bad (_("output_data buffer is too small"));
+ return 0;
+ }
+
+ switch (type)
+ {
+ case t_byte:
+ *ptr = (char) value;
+ if (verbose)
+ printf ("\t.byte\t0x%x\n", (unsigned char) *ptr);
+ break;
+ case t_half:
+ *(short *) ptr = (short) value & 0xFFFF;
+ if (verbose)
+ printf ("\t.half\t0x%x\n", (unsigned short) *ptr);
+ break;
+ case t_long:
+ *(int *) ptr = (int) value & 0xFFFFFFFF;
+ if (verbose)
+ printf ("\t.long\t0x%x\n", (unsigned int) *ptr);
+ break;
+ case t_quad:
+ *(long long *) ptr = (long long) value & 0xFFFFFFFF;
+ if (verbose)
+ printf ("\t.quad\t0x%x\n", (unsigned int) *ptr);
+ break;
+ case t_uleb128:
+ case t_sleb128:
+ ret_size = output_leb128 (ptr, value, type == t_sleb128);
+ if (verbose)
+ printf ("\t.%s\t0x%lx\n",
+ type == t_sleb128 ? "sleb128" : "uleb128",
+ value);
+ break;
+ default:
+ as_warn ("unknown type %d", type);
+ return 0;
+ }
+
+ *size -= ret_size;
+ *p += ret_size;
+
+ return ret_size;
+}
+
+static int
+cfi_output_insn (struct cfi_data *data, char **buf, unsigned long *buf_size)
+{
+ char **pbuf = buf, *orig_buf = *buf;
+ unsigned long size;
+
+ if (!data || !buf)
+ as_fatal (_("cfi_output_insn called with NULL pointer"));
+
+ switch (data->insn)
+ {
+ case CFA_advance_loc:
+ if (verbose)
+ printf ("\t# %s(%ld)\n", cfi_insn_str (data->insn),
+ data->param[0]);
+ if (data->param[0] <= 0x3F)
+ {
+ output_data (pbuf, buf_size, t_byte, CFA_advance_loc +
+ (data->param[0] / current_config.code_align));
+ }
+ else if (data->param[0] <= 0xFF)
+ {
+ output_data (pbuf, buf_size, t_byte, CFA_advance_loc1);
+ output_data (pbuf, buf_size, t_byte,
+ data->param[0] / current_config.code_align);
+ }
+ else if (data->param[0] <= 0xFFFF)
+ {
+ output_data (pbuf, buf_size, t_byte, CFA_advance_loc2);
+ output_data (pbuf, buf_size, t_half,
+ data->param[0] / current_config.code_align);
+ }
+ else
+ {
+ output_data (pbuf, buf_size, t_byte, CFA_advance_loc4);
+ output_data (pbuf, buf_size, t_long,
+ data->param[0] / current_config.code_align);
+ }
+ break;
+
+ case CFA_def_cfa:
+ if (verbose)
+ printf ("\t# CFA_def_cfa(%ld,%ld)\n", data->param[0], data->param[1]);
+ output_data (pbuf, buf_size, t_byte, CFA_def_cfa);
+ output_data (pbuf, buf_size, t_uleb128, data->param[0]);
+ output_data (pbuf, buf_size, t_uleb128, data->param[1]);
+ break;
+
+ case CFA_def_cfa_register:
+ case CFA_def_cfa_offset:
+ if (verbose)
+ printf ("\t# %s(%ld)\n", cfi_insn_str (data->insn),
+ data->param[0]);
+ output_data (pbuf, buf_size, t_byte, data->insn);
+ output_data (pbuf, buf_size, t_uleb128, data->param[0]);
+ break;
+
+ case CFA_offset:
+ if (verbose)
+ printf ("\t# %s(%ld,%ld)\n", cfi_insn_str (data->insn),
+ data->param[0], data->param[1]);
+
+ /* Check whether to use CFA_offset or CFA_offset_extended. */
+ if (data->param[0] <= 0x3F)
+ output_data (pbuf, buf_size, t_byte, CFA_offset + data->param[0]);
+ else
+ {
+ output_data (pbuf, buf_size, t_byte, CFA_offset_extended);
+ output_data (pbuf, buf_size, t_uleb128, data->param[0]);
+ }
+ output_data (pbuf, buf_size, t_uleb128,
+ data->param[1] / current_config.data_align);
+ break;
+
+ case CFA_nop:
+ if (verbose)
+ printf ("\t# CFA_nop\n");
+ output_data (pbuf, buf_size, t_byte, CFA_nop);
+ break;
+
+ default:
+ as_warn ("CFA_unknown[%d](%ld,%ld)", data->insn,
+ data->param[0], data->param[1]);
+ }
+ size = *pbuf - orig_buf;
+ *buf = *pbuf;
+ *buf_size -= size;
+ return size;
+}
+
+static void
+dot_cfi_endproc (void)
+{
+ struct cfi_data *data_ptr;
+ char *cie_buf, *fde_buf, *pbuf, *where;
+ unsigned long buf_size, cie_size, fde_size, last_cie_offset;
+ unsigned long fde_initloc_offset, fde_len_offset;
+ void *saved_seg, *cfi_seg;
+
+ if (! cfi_info)
+ {
+ as_bad (_(".cfi_endproc without corresponding .cfi_startproc"));
+ return;
+ }
+ cfi_info->end_address = frag_now_fix ();
+
+ /* Open .eh_frame section. */
+ saved_seg = now_seg;
+ cfi_seg = subseg_new (".eh_frame", 0);
+ bfd_set_section_flags (stdoutput, cfi_seg,
+ SEC_ALLOC | SEC_LOAD | SEC_RELOC | SEC_DATA);
+ subseg_set (cfi_seg, 0);
+
+ /* Build CIE. */
+ cie_buf = xcalloc (1024, 1);
+ /* Skip space for CIE length. */
+ pbuf = cie_buf + 4;
+ buf_size = 1020;
+
+ if (verbose)
+ printf ("# CIE *****\n");
+
+ /* CIE id. */
+ output_data (&pbuf, &buf_size, t_long, 0x0);
+ /* Version. */
+ output_data (&pbuf, &buf_size, t_byte, 1);
+ /* Augmentation. */
+ output_data (&pbuf, &buf_size, t_byte, 0);
+ /* Code alignment. */
+ output_data (&pbuf, &buf_size, t_uleb128, current_config.code_align);
+ /* Data alignment. */
+ output_data (&pbuf, &buf_size, t_sleb128, current_config.data_align);
+ /* Return address column. */
+ output_data (&pbuf, &buf_size, t_byte, current_config.ra_column);
+
+ /* Build CFI instructions. */
+ data_ptr = cfi_info->data;
+ while (data_ptr && !cfi_is_advance_insn (data_ptr->insn))
+ {
+ cfi_output_insn (data_ptr, &pbuf, &buf_size);
+ data_ptr = data_ptr->next;
+ }
+
+ /* Align the whole data to current_config.eh_align. */
+ cie_size = pbuf - cie_buf;
+ cie_size += current_config.eh_align - cie_size % current_config.eh_align;
+
+ /* CIE length. */
+ pbuf = cie_buf;
+ output_data (&pbuf, &buf_size, t_long, cie_size - 4);
+
+ /* OK, we built the CIE. Let's write it to the file... */
+ last_cie_offset = frag_now_fix ();
+ where = (unsigned char *) frag_more (cie_size);
+ memcpy (where, cie_buf, cie_size);
+
+ /* Clean up. */
+ free (cie_buf);
+
+ /* Build the FDE... */
+ fde_buf = xcalloc (1024, 1);
+ pbuf = fde_buf;
+ buf_size = 1024;
+
+ if (verbose)
+ {
+ printf ("# FDE: start=0x%lx, end=0x%lx, delta=%d\n",
+ (long) cfi_info->start_address,
+ (long) cfi_info->end_address,
+ (int) (cfi_info->end_address - cfi_info->start_address));
+ }
+
+ /* FDE length (t_long, 4 bytes) - will be set later. */
+ fde_len_offset = pbuf - fde_buf;
+ pbuf += 4;
+ buf_size -= 4;
+
+ /* CIE pointer - offset from here. */
+ output_data (&pbuf, &buf_size, t_long, cie_size + 4);
+
+ /* FDE initial location - this must be set relocatable! */
+ fde_initloc_offset = pbuf - fde_buf;
+ output_data (&pbuf, &buf_size, current_config.addr_length,
+ cfi_info->start_address);
+
+ /* FDE address range. */
+ output_data (&pbuf, &buf_size, current_config.addr_length,
+ cfi_info->end_address - cfi_info->start_address);
+
+ while (data_ptr)
+ {
+ cfi_output_insn (data_ptr, &pbuf, &buf_size);
+ data_ptr = data_ptr->next;
+ }
+
+ fde_size = pbuf - fde_buf;
+ fde_size += current_config.eh_align - fde_size % current_config.eh_align;
+
+ /* Now we can set FDE length. */
+ pbuf = fde_buf + fde_len_offset;
+ buf_size = 4;
+ output_data (&pbuf, &buf_size, t_long, fde_size - 4);
+
+ /* Adjust initloc offset. */
+ fde_initloc_offset += frag_now_fix ();
+
+ /* Copy FDE to objfile. */
+ where = (unsigned char *) frag_more (fde_size);
+ memcpy (where, fde_buf, fde_size);
+
+ /* Set relocation for initial address. */
+ buf_size = current_config.addr_length;
+ expressionS exp;
+ memset (&exp, 0, sizeof (exp));
+ exp.X_op = O_symbol;
+ exp.X_add_symbol = symbol_find (cfi_info->labelname);
+ fix_new_exp (frag_now, fde_initloc_offset,
+ current_config.addr_length,
+ &exp, 0, current_config.reloc_type);
+
+ /* Clean up. */
+ free (fde_buf);
+
+ free (cfi_info);
+ cfi_info = NULL;
+
+ /* Restore previous segment. */
+ subseg_set (saved_seg, 0);
+}
+
+void
+dot_cfi (int arg)
+{
+ long param;
+
+ switch (arg)
+ {
+ case CFI_startproc:
+ dot_cfi_startproc ();
+ break;
+ case CFI_endproc:
+ dot_cfi_endproc ();
+ break;
+ case CFA_def_cfa:
+ case CFA_def_cfa_register:
+ case CFA_def_cfa_offset:
+ case CFA_offset:
+ case CFI_adjust_cfa_offset:
+ cfi_make_insn (arg);
+ break;
+ case CFI_verbose:
+ if (cfi_parse_const (&param) >= 0)
+ verbose = (int) param;
+ else
+ verbose = 1;
+ break;
+ default:
+ as_bad (_("unknown CFI code 0x%x (%s)"), arg, cfi_insn_str (arg));
+ break;
+ }
+ ignore_rest_of_line ();
+}
+
+void
+cfi_set_config (struct cfi_config *cfg)
+{
+ assert (cfg != NULL);
+ assert (cfg->addr_length > 0);
+
+ current_config = *cfg;
+}
+
+void
+cfi_finish (void)
+{
+ if (cfi_info)
+ as_bad (_("open CFI at the end of file; missing .cfi_endproc directive"));
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-15 12:47:53 +0000