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-rw-r--r--gas/config/tc-tic6x.c997
1 files changed, 996 insertions, 1 deletions
diff --git a/gas/config/tc-tic6x.c b/gas/config/tc-tic6x.c
index 15ce88a..73bea63 100644
--- a/gas/config/tc-tic6x.c
+++ b/gas/config/tc-tic6x.c
@@ -23,6 +23,7 @@
#include "as.h"
#include "dwarf2dbg.h"
+#include "dw2gencfi.h"
#include "safe-ctype.h"
#include "subsegs.h"
#include "opcode/tic6x.h"
@@ -34,6 +35,8 @@
#define TRUNC(X) ((valueT) (X) & 0xffffffffU)
#define SEXT(X) ((TRUNC (X) ^ 0x80000000U) - 0x80000000U)
+#define streq(a, b) (strcmp (a, b) == 0)
+
/* Stuff for .scomm symbols. */
static segT sbss_section;
static asection scom_section;
@@ -162,6 +165,49 @@ static const tic6x_arch_table tic6x_arches[] =
| TIC6X_INSN_C674X) }
};
+/* Caller saved register encodings. The standard frame layout uses this
+ order, starting from the highest address. There must be
+ TIC6X_NUM_UNWIND_REGS values. */
+enum
+{
+ UNWIND_A15,
+ UNWIND_B15,
+ UNWIND_B14,
+ UNWIND_B13,
+ UNWIND_B12,
+ UNWIND_B11,
+ UNWIND_B10,
+ UNWIND_B3,
+ UNWIND_A14,
+ UNWIND_A13,
+ UNWIND_A12,
+ UNWIND_A11,
+ UNWIND_A10
+};
+
+static void tic6x_output_unwinding (bfd_boolean need_extab);
+
+/* Return the frame unwind state for the current function, allocating
+ as necessary. */
+
+static tic6x_unwind_info *tic6x_get_unwind (void)
+{
+ tic6x_unwind_info *unwind;
+
+ unwind = seg_info (now_seg)->tc_segment_info_data.unwind;
+ if (unwind)
+ return unwind;
+
+ unwind = seg_info (now_seg)->tc_segment_info_data.text_unwind;
+ if (unwind)
+ return unwind;
+
+ unwind = (tic6x_unwind_info *)xmalloc (sizeof (tic6x_unwind_info));
+ seg_info (now_seg)->tc_segment_info_data.unwind = unwind;
+ memset (unwind, 0, sizeof (*unwind));
+ return unwind;
+}
+
/* Update the selected architecture based on ARCH, giving an error if
ARCH is an invalid value. Does not call tic6x_update_features; the
caller must do that if necessary. */
@@ -325,9 +371,123 @@ tic6x_after_parse_args (void)
tic6x_update_features ();
}
-/* Parse a .arch directive. */
+/* Parse a .cantunwind directive. */
+static void
+s_tic6x_cantunwind (int ignored ATTRIBUTE_UNUSED)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ /* GCC sometimes spits out superfluous .cantunwind directives, so ignore
+ them. */
+ if (unwind->data_bytes == 0)
+ return;
+
+ if (unwind->data_bytes != -1)
+ {
+ as_bad (_("unexpected .cantunwind directive"));
+ return;
+ }
+
+ demand_empty_rest_of_line ();
+
+ if (unwind->personality_routine || unwind->personality_index != -1)
+ as_bad (_("personality routine specified for cantunwind frame"));
+
+ unwind->personality_index = -2;
+}
+
+/* Parse a .handlerdata directive. */
+static void
+s_tic6x_handlerdata (int ignored ATTRIBUTE_UNUSED)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ if (!unwind->saved_seg)
+ {
+ as_bad (_("unexpected .handlerdata directive"));
+ return;
+ }
+
+ if (unwind->table_entry || unwind->personality_index == -2)
+ {
+ as_bad (_("duplicate .handlerdata directive"));
+ return;
+ }
+
+ if (unwind->personality_index == -1 && unwind->personality_routine == NULL)
+ {
+ as_bad (_("personality routine required before .handlerdata directive"));
+ return;
+ }
+
+ tic6x_output_unwinding (TRUE);
+}
+
+/* Parse a .endp directive. */
+static void
+s_tic6x_endp (int ignored ATTRIBUTE_UNUSED)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ if (unwind->data_bytes != 0)
+ {
+ /* Output a .exidx entry if we have not already done so.
+ Then switch back to the text section. */
+ if (!unwind->table_entry)
+ tic6x_output_unwinding (FALSE);
+
+ subseg_set (unwind->saved_seg, unwind->saved_subseg);
+ }
+
+ unwind->saved_seg = NULL;
+ unwind->table_entry = NULL;
+ unwind->data_bytes = 0;
+}
+
+/* Parse a .personalityindex directive. */
+static void
+s_tic6x_personalityindex (int ignored ATTRIBUTE_UNUSED)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+ expressionS exp;
+
+ if (unwind->personality_routine || unwind->personality_index != -1)
+ as_bad (_("duplicate .personalityindex directive"));
+
+ expression (&exp);
+
+ if (exp.X_op != O_constant
+ || exp.X_add_number < 0 || exp.X_add_number > 15)
+ {
+ as_bad (_("bad personality routine number"));
+ ignore_rest_of_line ();
+ return;
+ }
+
+ unwind->personality_index = exp.X_add_number;
+
+ demand_empty_rest_of_line ();
+}
static void
+s_tic6x_personality (int ignored ATTRIBUTE_UNUSED)
+{
+ char *name, *p, c;
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ if (unwind->personality_routine || unwind->personality_index != -1)
+ as_bad (_("duplicate .personality directive"));
+
+ name = input_line_pointer;
+ c = get_symbol_end ();
+ p = input_line_pointer;
+ unwind->personality_routine = symbol_find_or_make (name);
+ *p = c;
+ demand_empty_rest_of_line ();
+}
+
+/* Parse a .arch directive. */
+static void
s_tic6x_arch (int ignored ATTRIBUTE_UNUSED)
{
char c;
@@ -574,6 +734,11 @@ const pseudo_typeS md_pseudo_table[] =
{ "scomm", s_tic6x_scomm, 0 },
{ "word", cons, 4 },
{ "ehtype", s_tic6x_ehtype, 0 },
+ { "endp", s_tic6x_endp, 0 },
+ { "handlerdata", s_tic6x_handlerdata, 0 },
+ { "personalityindex", s_tic6x_personalityindex, 0 },
+ { "personality", s_tic6x_personality, 0 },
+ { "cantunwind", s_tic6x_cantunwind, 0 },
{ 0, 0, 0 }
};
@@ -1843,6 +2008,9 @@ tic6x_fix_adjustable (fixS *fixP)
case BFD_RELOC_C6000_EHTYPE:
return 0;
+ case BFD_RELOC_C6000_PREL31:
+ return 0;
+
default:
return 1;
}
@@ -3806,6 +3974,11 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
}
break;
+ case BFD_RELOC_C6000_PREL31:
+ /* Force output to the object file. */
+ fixP->fx_done = 0;
+ break;
+
default:
abort ();
}
@@ -4267,3 +4440,825 @@ tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixp)
return reloc;
}
+
+/* Convert REGNAME to a DWARF-2 register number. */
+
+int
+tic6x_regname_to_dw2regnum (char *regname)
+{
+ bfd_boolean reg_ok;
+ tic6x_register reg;
+ char *rq = regname;
+
+ reg_ok = tic6x_parse_register (&rq, &reg);
+
+ if (!reg_ok)
+ return -1;
+
+ switch (reg.side)
+ {
+ case 1: /* A regs. */
+ if (reg.num < 16)
+ return reg.num;
+ else if (reg.num < 32)
+ return (reg.num - 16) + 37;
+ else
+ return -1;
+
+ case 2: /* B regs. */
+ if (reg.num < 16)
+ return reg.num + 16;
+ else if (reg.num < 32)
+ return (reg.num - 16) + 53;
+ else
+ return -1;
+
+ default:
+ return -1;
+ }
+}
+
+/* Initialize the DWARF-2 unwind information for this procedure. */
+
+void
+tic6x_frame_initial_instructions (void)
+{
+ /* CFA is initial stack pointer (B15). */
+ cfi_add_CFA_def_cfa (31, 0);
+}
+
+/* Start an exception table entry. If idx is nonzero this is an index table
+ entry. */
+
+static void
+tic6x_start_unwind_section (const segT text_seg, int idx)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+ const char * text_name;
+ const char * prefix;
+ const char * prefix_once;
+ const char * group_name;
+ size_t prefix_len;
+ size_t text_len;
+ char * sec_name;
+ size_t sec_name_len;
+ int type;
+ int flags;
+ int linkonce;
+
+ if (idx)
+ {
+ prefix = ELF_STRING_C6000_unwind;
+ prefix_once = ELF_STRING_C6000_unwind_once;
+ type = SHT_C6000_UNWIND;
+ }
+ else
+ {
+ prefix = ELF_STRING_C6000_unwind_info;
+ prefix_once = ELF_STRING_C6000_unwind_info_once;
+ type = SHT_PROGBITS;
+ }
+
+ text_name = segment_name (text_seg);
+ if (streq (text_name, ".text"))
+ text_name = "";
+
+ if (strncmp (text_name, ".gnu.linkonce.t.",
+ strlen (".gnu.linkonce.t.")) == 0)
+ {
+ prefix = prefix_once;
+ text_name += strlen (".gnu.linkonce.t.");
+ }
+
+ prefix_len = strlen (prefix);
+ text_len = strlen (text_name);
+ sec_name_len = prefix_len + text_len;
+ sec_name = (char *) xmalloc (sec_name_len + 1);
+ memcpy (sec_name, prefix, prefix_len);
+ memcpy (sec_name + prefix_len, text_name, text_len);
+ sec_name[prefix_len + text_len] = '\0';
+
+ flags = SHF_ALLOC;
+ linkonce = 0;
+ group_name = 0;
+
+ /* Handle COMDAT group. */
+ if (prefix != prefix_once && (text_seg->flags & SEC_LINK_ONCE) != 0)
+ {
+ group_name = elf_group_name (text_seg);
+ if (group_name == NULL)
+ {
+ as_bad (_("group section `%s' has no group signature"),
+ segment_name (text_seg));
+ ignore_rest_of_line ();
+ return;
+ }
+ flags |= SHF_GROUP;
+ linkonce = 1;
+ }
+
+ obj_elf_change_section (sec_name, type, flags, 0, group_name, linkonce, 0);
+
+ /* Set the section link for index tables. */
+ if (idx)
+ elf_linked_to_section (now_seg) = text_seg;
+
+ seg_info (now_seg)->tc_segment_info_data.text_unwind = unwind;
+}
+
+
+static const int
+tic6x_unwind_frame_regs[TIC6X_NUM_UNWIND_REGS] =
+/* A15 B15 B14 B13 B12 B11 B10 B3 A14 A13 A12 A11 A10. */
+ { 15, 31, 30, 29, 28, 27, 26, 19, 14, 13, 12, 11, 10 };
+
+/* Register save offsets for __c6xabi_push_rts. */
+static const int
+tic6x_pop_rts_offset_little[TIC6X_NUM_UNWIND_REGS] =
+/* A15 B15 B14 B13 B12 B11 B10 B3 A14 A13 A12 A11 A10. */
+ { -1, 1, 0, -3, -4, -7, -8,-11, -2, -5, -6, -9,-10};
+
+static const int
+tic6x_pop_rts_offset_big[TIC6X_NUM_UNWIND_REGS] =
+/* A15 B15 B14 B13 B12 B11 B10 B3 A14 A13 A12 A11 A10. */
+ { -2, 1, 0, -4, -3, -8, -7,-12, -1, -6, -5,-10, -9};
+
+/* Map from dwarf register number to unwind frame register number. */
+static int
+tic6x_unwind_reg_from_dwarf (int dwarf)
+{
+ int reg;
+
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ if (tic6x_unwind_frame_regs[reg] == dwarf)
+ return reg;
+ }
+
+ return -1;
+}
+
+/* Unwinding bytecode definitions. */
+#define UNWIND_OP_ADD_SP 0x00
+#define UNWIND_OP_ADD_SP2 0xd2
+#define UNWIND_OP2_POP 0x8000
+#define UNWIND_OP2_POP_COMPACT 0xa000
+#define UNWIND_OP_POP_REG 0xc0
+#define UNWIND_OP_MV_FP 0xd0
+#define UNWIND_OP_POP_RTS 0xd1
+#define UNWIND_OP_RET 0xe0
+
+/* Maximum stack adjustment for __c6xabi_unwind_cpp_pr3/4 */
+#define MAX_COMPACT_SP_OFFSET (0x7f << 3)
+
+static void
+tic6x_flush_unwind_word (valueT data)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+ char *ptr;
+
+ /* Create EXTAB entry if it does not exist. */
+ if (unwind->table_entry == NULL)
+ {
+ tic6x_start_unwind_section (unwind->saved_seg, 0);
+ frag_align (2, 0, 0);
+ record_alignment (now_seg, 2);
+ unwind->table_entry = expr_build_dot ();
+ ptr = frag_more (4);
+ unwind->frag_start = ptr;
+ }
+ else
+ {
+ /* Append additional word of data. */
+ ptr = frag_more (4);
+ }
+
+ md_number_to_chars (ptr, data, 4);
+}
+
+/* Add a single byte of unwinding data. */
+
+static void
+tic6x_unwind_byte (int byte)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ unwind->data_bytes++;
+ /* Only flush the first word after we know multiple words are required. */
+ if (unwind->data_bytes == 5)
+ {
+ if (unwind->personality_index == -1)
+ {
+ /* At this point we know we are too big for pr0. */
+ unwind->personality_index = 1;
+ tic6x_flush_unwind_word (0x81000000 | ((unwind->data >> 8) & 0xffff));
+ unwind->data = ((unwind->data & 0xff) << 8) | byte;
+ unwind->data_bytes++;
+ }
+ else
+ {
+ tic6x_flush_unwind_word (unwind->data);
+ unwind->data = byte;
+ }
+ }
+ else
+ {
+ unwind->data = (unwind->data << 8) | byte;
+ if ((unwind->data_bytes & 3) == 0 && unwind->data_bytes > 4)
+ {
+ tic6x_flush_unwind_word (unwind->data);
+ unwind->data = 0;
+ }
+ }
+}
+
+/* Add a two-byte unwinding opcode. */
+static void
+tic6x_unwind_2byte (int bytes)
+{
+ tic6x_unwind_byte (bytes >> 8);
+ tic6x_unwind_byte (bytes & 0xff);
+}
+
+static void
+tic6x_unwind_uleb (offsetT offset)
+{
+ while (offset > 0x7f)
+ {
+ tic6x_unwind_byte ((offset & 0x7f) | 0x80);
+ offset >>= 7;
+ }
+ tic6x_unwind_byte (offset);
+}
+
+void
+tic6x_cfi_startproc (void)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ unwind->personality_index = -1;
+ unwind->personality_routine = NULL;
+ if (unwind->table_entry)
+ as_bad (_("missing .endp before .cfi_startproc"));
+
+ unwind->table_entry = NULL;
+ unwind->data_bytes = -1;
+}
+
+static void
+tic6x_output_exidx_entry (void)
+{
+ char *ptr;
+ long where;
+ unsigned int marked_pr_dependency;
+ segT old_seg;
+ subsegT old_subseg;
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+
+ old_seg = now_seg;
+ old_subseg = now_subseg;
+
+ /* Add index table entry. This is two words. */
+ tic6x_start_unwind_section (unwind->saved_seg, 1);
+ frag_align (2, 0, 0);
+ record_alignment (now_seg, 2);
+
+ ptr = frag_more (8);
+ where = frag_now_fix () - 8;
+
+ /* Self relative offset of the function start. */
+ fix_new (frag_now, where, 4, unwind->function_start, 0, 1,
+ BFD_RELOC_C6000_PREL31);
+
+ /* Indicate dependency on ABI-defined personality routines to the
+ linker, if it hasn't been done already. */
+ marked_pr_dependency
+ = seg_info (now_seg)->tc_segment_info_data.marked_pr_dependency;
+ if (unwind->personality_index >= 0 && unwind->personality_index < 5
+ && !(marked_pr_dependency & (1 << unwind->personality_index)))
+ {
+ static const char *const name[] =
+ {
+ "__c6xabi_unwind_cpp_pr0",
+ "__c6xabi_unwind_cpp_pr1",
+ "__c6xabi_unwind_cpp_pr2",
+ "__c6xabi_unwind_cpp_pr3",
+ "__c6xabi_unwind_cpp_pr4"
+ };
+ symbolS *pr = symbol_find_or_make (name[unwind->personality_index]);
+ fix_new (frag_now, where, 0, pr, 0, 1, BFD_RELOC_NONE);
+ seg_info (now_seg)->tc_segment_info_data.marked_pr_dependency
+ |= 1 << unwind->personality_index;
+ }
+
+ if (unwind->table_entry)
+ {
+ /* Self relative offset of the table entry. */
+ fix_new (frag_now, where + 4, 4, unwind->table_entry, 0, 1,
+ BFD_RELOC_C6000_PREL31);
+ }
+ else
+ {
+ /* Inline exception table entry. */
+ md_number_to_chars (ptr + 4, unwind->data, 4);
+ }
+
+ /* Restore the original section. */
+ subseg_set (old_seg, old_subseg);
+}
+
+static void
+tic6x_output_unwinding (bfd_boolean need_extab)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+ unsigned safe_mask = unwind->safe_mask;
+ unsigned compact_mask = unwind->compact_mask;
+ unsigned reg_saved_mask = unwind->reg_saved_mask;
+ offsetT cfa_offset = unwind->cfa_offset;
+ long where;
+ int reg;
+
+ if (unwind->personality_index == -2)
+ {
+ /* Function can not be unwound. */
+ unwind->data = 1;
+ tic6x_output_exidx_entry ();
+ return;
+ }
+
+ if (unwind->personality_index == -1 && unwind->personality_routine == NULL)
+ {
+ /* Auto-select a personality routine if none specified. */
+ if (reg_saved_mask || cfa_offset >= MAX_COMPACT_SP_OFFSET)
+ unwind->personality_index = -1;
+ else if (safe_mask)
+ unwind->personality_index = 3;
+ else
+ unwind->personality_index = 4;
+ }
+
+ /* Calculate unwinding opcodes, and emit to EXTAB if necessary. */
+ unwind->table_entry = NULL;
+ if (unwind->personality_index == 3 || unwind->personality_index == 4)
+ {
+ if (cfa_offset >= MAX_COMPACT_SP_OFFSET)
+ {
+ as_bad (_("stack pointer offset too large for personality routine"));
+ return;
+ }
+ if (reg_saved_mask
+ || (unwind->personality_index == 3 && compact_mask != 0)
+ || (unwind->personality_index == 4 && safe_mask != 0))
+ {
+ as_bad (_("stack frame layout does not match personality routine"));
+ return;
+ }
+
+ unwind->data = (1u << 31) | (unwind->personality_index << 24);
+ if (unwind->cfa_reg == 15)
+ unwind->data |= 0x7f << 17;
+ else
+ unwind->data |= cfa_offset << (17 - 3);
+
+ if (unwind->personality_index == 3)
+ unwind->data |= safe_mask << 4;
+ else
+ unwind->data |= compact_mask << 4;
+ unwind->data |= unwind->return_reg;
+ unwind->data_bytes = 4;
+ }
+ else
+ {
+ if (unwind->personality_routine)
+ {
+ unwind->data = 0;
+ unwind->data_bytes = 5;
+ tic6x_flush_unwind_word (0);
+ /* First word is personality routine. */
+ where = frag_now_fix () - 4;
+ fix_new (frag_now, where, 4, unwind->personality_routine, 0, 1,
+ BFD_RELOC_C6000_PREL31);
+ }
+ else if (unwind->personality_index > 0)
+ {
+ unwind->data = 0x8000 | (unwind->personality_index << 8);
+ unwind->data_bytes = 2;
+ }
+ else /* pr0 or undecided */
+ {
+ unwind->data = 0x80;
+ unwind->data_bytes = 1;
+ }
+
+ if (unwind->return_reg != UNWIND_B3)
+ {
+ tic6x_unwind_byte (UNWIND_OP_RET | unwind->return_reg);
+ }
+
+ if (unwind->cfa_reg == 15)
+ {
+ tic6x_unwind_byte (UNWIND_OP_MV_FP);
+ }
+ else if (cfa_offset != 0)
+ {
+ cfa_offset >>= 3;
+ if (cfa_offset > 0x80)
+ {
+ tic6x_unwind_byte (UNWIND_OP_ADD_SP2);
+ tic6x_unwind_uleb (cfa_offset - 0x81);
+ }
+ else if (cfa_offset > 0x40)
+ {
+ tic6x_unwind_byte (UNWIND_OP_ADD_SP | 0x3f);
+ tic6x_unwind_byte (UNWIND_OP_ADD_SP | (cfa_offset - 0x40));
+ }
+ else
+ {
+ tic6x_unwind_byte (UNWIND_OP_ADD_SP | (cfa_offset - 1));
+ }
+ }
+
+ if (safe_mask)
+ tic6x_unwind_2byte (UNWIND_OP2_POP | unwind->safe_mask);
+ else if (unwind->pop_rts)
+ tic6x_unwind_byte (UNWIND_OP_POP_RTS);
+ else if (compact_mask)
+ tic6x_unwind_2byte (UNWIND_OP2_POP_COMPACT | unwind->compact_mask);
+ else if (reg_saved_mask)
+ {
+ offsetT cur_offset;
+ int val;
+ int last_val;
+
+ tic6x_unwind_byte (UNWIND_OP_POP_REG | unwind->saved_reg_count);
+ last_val = 0;
+ for (cur_offset = 0; unwind->saved_reg_count > 0; cur_offset -= 4)
+ {
+ val = 0xf;
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ if (!unwind->reg_saved[reg])
+ continue;
+
+ if (unwind->reg_offset[reg] == cur_offset)
+ {
+ unwind->saved_reg_count--;
+ val = reg;
+ break;
+ }
+ }
+ if ((cur_offset & 4) == 4)
+ tic6x_unwind_byte ((last_val << 4) | val);
+ else
+ last_val = val;
+ }
+ if ((cur_offset & 4) == 4)
+ tic6x_unwind_byte ((last_val << 4) | 0xf);
+ }
+
+ /* Pad with RETURN opcodes. */
+ while ((unwind->data_bytes & 3) != 0)
+ tic6x_unwind_byte (UNWIND_OP_RET | UNWIND_B3);
+
+ if (unwind->personality_index == -1 && unwind->personality_routine == NULL)
+ unwind->personality_index = 0;
+ }
+
+ /* Force creation of an EXTAB entry if an LSDA is required. */
+ if (need_extab && !unwind->table_entry)
+ {
+ if (unwind->data_bytes != 4)
+ abort ();
+
+ tic6x_flush_unwind_word (unwind->data);
+ }
+ else if (unwind->table_entry && !need_extab)
+ {
+ /* Add an empty descriptor if there is no user-specified data. */
+ char *ptr = frag_more (4);
+ md_number_to_chars (ptr, 0, 4);
+ }
+
+ /* Fill in length of unwinding bytecode. */
+ if (unwind->table_entry)
+ {
+ valueT tmp;
+ if (unwind->data_bytes > 0x400)
+ as_bad (_("too many unwinding instructions"));
+
+ if (unwind->personality_index == -1)
+ {
+ tmp = md_chars_to_number (unwind->frag_start + 4, 4);
+ tmp |= ((unwind->data_bytes - 8) >> 2) << 24;
+ md_number_to_chars (unwind->frag_start + 4, tmp, 4);
+ }
+ else if (unwind->personality_index == 1 || unwind->personality_index == 2)
+ {
+ tmp = md_chars_to_number (unwind->frag_start, 4);
+ tmp |= ((unwind->data_bytes - 4) >> 2) << 16;
+ md_number_to_chars (unwind->frag_start, tmp, 4);
+ }
+ }
+ tic6x_output_exidx_entry ();
+}
+
+/* FIXME: This will get horribly confused if cfi directives are emitted for
+ function epilogue. */
+void
+tic6x_cfi_endproc (struct fde_entry *fde)
+{
+ tic6x_unwind_info *unwind = tic6x_get_unwind ();
+ struct cfi_insn_data *insn;
+ int reg;
+ unsigned safe_mask = 0;
+ unsigned compact_mask = 0;
+ unsigned reg_saved_mask = 0;
+ offsetT cfa_offset = 0;
+ offsetT save_offset = 0;
+
+ unwind->cfa_reg = 31;
+ unwind->return_reg = UNWIND_B3;
+ unwind->saved_reg_count = 0;
+ unwind->pop_rts = FALSE;
+
+ unwind->saved_seg = now_seg;
+ unwind->saved_subseg = now_subseg;
+
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ unwind->reg_saved[reg] = FALSE;
+
+ /* Scan FDE instructions to build up stack frame layout. */
+ for (insn = fde->data; insn; insn = insn->next)
+ {
+ switch (insn->insn)
+ {
+ case DW_CFA_advance_loc:
+ break;
+
+ case DW_CFA_def_cfa:
+ unwind->cfa_reg = insn->u.ri.reg;
+ cfa_offset = insn->u.ri.offset;
+ break;
+
+ case DW_CFA_def_cfa_register:
+ unwind->cfa_reg = insn->u.r;
+ break;
+
+ case DW_CFA_def_cfa_offset:
+ cfa_offset = insn->u.i;
+ break;
+
+ case DW_CFA_undefined:
+ case DW_CFA_same_value:
+ reg = tic6x_unwind_reg_from_dwarf (insn->u.r);
+ if (reg >= 0)
+ unwind->reg_saved[reg] = FALSE;
+ break;
+
+ case DW_CFA_offset:
+ reg = tic6x_unwind_reg_from_dwarf (insn->u.ri.reg);
+ if (reg < 0)
+ {
+ as_bad (_("unable to generate unwinding opcode for reg %d"),
+ insn->u.ri.reg);
+ return;
+ }
+ unwind->reg_saved[reg] = TRUE;
+ unwind->reg_offset[reg] = insn->u.ri.offset;
+ if (insn->u.ri.reg == UNWIND_B3)
+ unwind->return_reg = UNWIND_B3;
+ break;
+
+ case DW_CFA_register:
+ if (insn->u.rr.reg1 != 19)
+ {
+ as_bad (_("unable to generate unwinding opcode for reg %d"),
+ insn->u.rr.reg1);
+ return;
+ }
+
+ reg = tic6x_unwind_reg_from_dwarf (insn->u.rr.reg2);
+ if (reg < 0)
+ {
+ as_bad (_("unable to generate unwinding opcode for reg %d"),
+ insn->u.rr.reg2);
+ return;
+ }
+
+ unwind->return_reg = reg;
+ unwind->reg_saved[UNWIND_B3] = FALSE;
+ if (unwind->reg_saved[reg])
+ {
+ as_bad (_("unable to restore return address from "
+ "previously restored reg"));
+ return;
+ }
+ break;
+
+ case DW_CFA_restore:
+ case DW_CFA_remember_state:
+ case DW_CFA_restore_state:
+ case DW_CFA_GNU_window_save:
+ case CFI_escape:
+ case CFI_val_encoded_addr:
+ as_bad (_("unhandled CFA insn for unwinding (%d)"), insn->insn);
+ break;
+
+ default:
+ abort ();
+ }
+ }
+
+ if (unwind->cfa_reg != 15 && unwind->cfa_reg != 31)
+ {
+ as_bad (_("unable to generate unwinding opcode for frame pointer reg %d"),
+ unwind->cfa_reg);
+ return;
+ }
+
+ if (unwind->cfa_reg == 15)
+ {
+ if (cfa_offset != 0)
+ {
+ as_bad (_("unable to generate unwinding opcode for "
+ "frame pointer offset"));
+ return;
+ }
+ }
+ else
+ {
+ if ((cfa_offset & 7) != 0)
+ {
+ as_bad (_("unwound stack pointer not doubleword aligned"));
+ return;
+ }
+ }
+
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ if (unwind->reg_saved[reg])
+ reg_saved_mask |= 1 << (TIC6X_NUM_UNWIND_REGS - (reg + 1));
+ }
+
+ /* Check for standard "safe debug" frame layout */
+ if (reg_saved_mask)
+ {
+ save_offset = 0;
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ if (!unwind->reg_saved[reg])
+ continue;
+
+ if (target_big_endian
+ && reg < TIC6X_NUM_UNWIND_REGS - 1
+ && unwind->reg_saved[reg + 1]
+ && tic6x_unwind_frame_regs[reg]
+ == tic6x_unwind_frame_regs[reg + 1] + 1
+ && (tic6x_unwind_frame_regs[reg] & 1) == 1
+ && (save_offset & 4) == 4)
+ {
+ /* Swapped pair */
+ if (save_offset != unwind->reg_offset[reg + 1]
+ || save_offset - 4 != unwind->reg_offset[reg])
+ break;
+ save_offset -= 8;
+ reg++;
+ }
+ else
+ {
+ if (save_offset != unwind->reg_offset[reg])
+ break;
+ save_offset -= 4;
+ }
+ }
+ if (reg == TIC6X_NUM_UNWIND_REGS)
+ {
+ safe_mask = reg_saved_mask;
+ reg_saved_mask = 0;
+ }
+ }
+
+ /* Check for compact frame layout. */
+ if (reg_saved_mask)
+ {
+ save_offset = 0;
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ int reg2;
+
+ if (!unwind->reg_saved[reg])
+ continue;
+
+ if (reg < TIC6X_NUM_UNWIND_REGS - 1)
+ {
+ reg2 = reg + 1;
+
+ if (!unwind->reg_saved[reg2]
+ || tic6x_unwind_frame_regs[reg]
+ != tic6x_unwind_frame_regs[reg2] + 1
+ || (tic6x_unwind_frame_regs[reg2] & 1) != 0
+ || save_offset == 0)
+ reg2 = -1;
+ }
+ else
+ reg2 = -1;
+
+ if (reg2 >= 0)
+ {
+ int high_offset;
+ if (target_big_endian)
+ high_offset = 4; /* lower address = positive stack offset. */
+ else
+ high_offset = 0;
+
+ if (save_offset + 4 - high_offset != unwind->reg_offset[reg]
+ || save_offset + high_offset != unwind->reg_offset[reg2])
+ {
+ break;
+ }
+ reg++;
+ }
+ else
+ {
+ if (save_offset != unwind->reg_offset[reg])
+ break;
+ }
+ save_offset -= 8;
+ }
+
+ if (reg == TIC6X_NUM_UNWIND_REGS)
+ {
+ compact_mask = reg_saved_mask;
+ reg_saved_mask = 0;
+ }
+ }
+
+ /* Check for __c6xabi_pop_rts format */
+ if (reg_saved_mask == 0x17ff)
+ {
+ const int *pop_rts_offset = target_big_endian
+ ? tic6x_pop_rts_offset_big
+ : tic6x_pop_rts_offset_little;
+
+ save_offset = 0;
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ if (reg == UNWIND_B15)
+ continue;
+
+ if (unwind->reg_offset[reg] != pop_rts_offset[reg] * 4)
+ break;
+ }
+
+ if (reg == TIC6X_NUM_UNWIND_REGS)
+ {
+ unwind->pop_rts = TRUE;
+ reg_saved_mask = 0;
+ }
+ }
+ /* If all else fails then describe the frame manually. */
+ if (reg_saved_mask)
+ {
+ save_offset = 0;
+
+ for (reg = 0; reg < TIC6X_NUM_UNWIND_REGS; reg++)
+ {
+ if (!unwind->reg_saved[reg])
+ continue;
+
+ unwind->saved_reg_count++;
+ /* Encoding uses 4 bits per word, so size of unwinding opcode data
+ limits the save area size. The exact cap will be figured out
+ later due to overflow, the 0x800 here is just a quick sanity
+ check to weed out obviously excessive offsets. */
+ if (unwind->reg_offset[reg] > 0 || unwind->reg_offset[reg] < -0x800
+ || (unwind->reg_offset[reg] & 3) != 0)
+ {
+ as_bad (_("stack frame layout too complex for unwinder"));
+ return;
+ }
+
+ if (unwind->reg_offset[reg] < save_offset)
+ save_offset = unwind->reg_offset[reg] - 4;
+ }
+ }
+
+ /* Align to 8-byte boundary (stack grows towards negative offsets). */
+ save_offset &= ~7;
+
+ if (unwind->cfa_reg == 31 && !reg_saved_mask)
+ {
+ cfa_offset += save_offset;
+ if (cfa_offset < 0)
+ {
+ as_bad (_("unwound frame has negative size"));
+ return;
+ }
+ }
+
+ unwind->safe_mask = safe_mask;
+ unwind->compact_mask = compact_mask;
+ unwind->reg_saved_mask = reg_saved_mask;
+ unwind->cfa_offset = cfa_offset;
+ unwind->function_start = fde->start_address;
+}
generated by cgit v1.1 at 2024-11-24 16:36:40 +0000