dwarf2.h (enum dwarf_call_frame_info): Add DW_CFA_def_cfa_expression.

        * dwarf2.h (enum dwarf_call_frame_info): Add
        DW_CFA_def_cfa_expression.
        * dwarf2out.c (union dw_cfi_oprnd_struct): Add a pointer to a
        dw_loc_descr_struct entry.
        (struct cfa_loc): New structure to track a CFA location.
        (lookup_cfa): Take a cfa_loc parameter instead of a reg and an offset.
        (lookup_cfa_1): Take a cfa_loc parameter instead of a reg and an
        offset, plus handle DW_CFA_def_cfa_expression.
        (def_cfa_1): Use to be dwarf2out_def_cfa, only now it uses a
        cfa_loc record.
        (dwarf2out_def_cfa): Entry point maintained for compatability.
        (dwarf_cfi_name): Add DW_CFA_def_cfa_expression.
        (cfa_reg, cfa_offset): Replace with cfa_loc record 'cfa'.
        (cfa_store_reg, cfa_store_offset): Replace with cfa_loc 'cfa_store'.
        (initial_return_save, dwarf2out_stack_adjust): Use cfa.reg, not
        cfa_reg.
        (dwarf2out_frame_debug_expr): Use new cfa_loc records. Recognize rtl
        sequences for the new DW_CFA_def_cfa_expression record.
        (dwarf2out_frame_debug): Use new variables/fields.A
        (output_cfi): Handle DW_CFA_def_cfa_expression.
        (output_cfa_loc): New function to generate a CFI record for
        DW_CFA_def_cfa_expression.
        (get_cfa_from_loc_descr): New function to get a cfa_loc record from
        a dw_loc_descr sequeunce.
        (build_loc_descr): Build a dw_loc_descr from a cfa_loc record.
        (dwarf_stack_op_name, new_loc_descr, add_loc_descr, size_of_loc_descr,
        size_of_locs, output_loc_operands, output_loc_sequence): Move into
        unwind info section.
        * frame.h (frame_state): Add base_offset and indirect fields.
        * frame-dwarf2.c (decode_stack_op): New function to interpret a
        dw_loc_descr operation.
        (execute_cfa_insn): Add support for DW_CFA_def_cfa_expression.
        (struct frame_state): Add base offset and indirect fields.
        * libgcc2.c (next_stack_level): Support indirect loading for CFA.

From-SVN: r34717

1 files changed, 116 insertions, 0 deletions

diff --git a/gcc/frame-dwarf2.c b/gcc/frame-dwarf2.c
index fb2e9fb..52db16f5 100644
--- a/gcc/frame-dwarf2.c
+++ b/gcc/frame-dwarf2.c
@@ -466,6 +466,108 @@ extract_cie_info (fde *f, struct cie_info *c)
   return p;
 }
 
+/* Decode a DW_OP stack operation.  */
+
+static void *
+decode_stack_op (unsigned char *buf, struct frame_state *state)
+{
+  enum dwarf_location_atom op;
+  int offset;
+
+  op = *buf++;
+  switch (op)
+    {
+    case DW_OP_reg0:
+    case DW_OP_reg1:
+    case DW_OP_reg2:
+    case DW_OP_reg3:
+    case DW_OP_reg4:
+    case DW_OP_reg5:
+    case DW_OP_reg6:
+    case DW_OP_reg7:
+    case DW_OP_reg8:
+    case DW_OP_reg9:
+    case DW_OP_reg10:
+    case DW_OP_reg11:
+    case DW_OP_reg12:
+    case DW_OP_reg13:
+    case DW_OP_reg14:
+    case DW_OP_reg15:
+    case DW_OP_reg16:
+    case DW_OP_reg17:
+    case DW_OP_reg18:
+    case DW_OP_reg19:
+    case DW_OP_reg20:
+    case DW_OP_reg21:
+    case DW_OP_reg22:
+    case DW_OP_reg23:
+    case DW_OP_reg24:
+    case DW_OP_reg25:
+    case DW_OP_reg26:
+    case DW_OP_reg27:
+    case DW_OP_reg28:
+    case DW_OP_reg29:
+    case DW_OP_reg30:
+    case DW_OP_reg31:
+      state->cfa_reg = op - DW_OP_reg0;
+      break;
+    case DW_OP_regx:
+      buf = decode_sleb128 (buf, &offset);
+      state->cfa_reg = offset;
+    case DW_OP_breg0:
+    case DW_OP_breg1:
+    case DW_OP_breg2:
+    case DW_OP_breg3:
+    case DW_OP_breg4:
+    case DW_OP_breg5:
+    case DW_OP_breg6:
+    case DW_OP_breg7:
+    case DW_OP_breg8:
+    case DW_OP_breg9:
+    case DW_OP_breg10:
+    case DW_OP_breg11:
+    case DW_OP_breg12:
+    case DW_OP_breg13:
+    case DW_OP_breg14:
+    case DW_OP_breg15:
+    case DW_OP_breg16:
+    case DW_OP_breg17:
+    case DW_OP_breg18:
+    case DW_OP_breg19:
+    case DW_OP_breg20:
+    case DW_OP_breg21:
+    case DW_OP_breg22:
+    case DW_OP_breg23:
+    case DW_OP_breg24:
+    case DW_OP_breg25:
+    case DW_OP_breg26:
+    case DW_OP_breg27:
+    case DW_OP_breg28:
+    case DW_OP_breg29:
+    case DW_OP_breg30:
+    case DW_OP_breg31:
+      state->cfa_reg = op - DW_OP_breg0;
+      buf = decode_sleb128 (buf, &offset);
+      state->base_offset = offset;
+      break;
+    case DW_OP_bregx:
+      buf = decode_sleb128 (buf, &offset);
+      state->cfa_reg = offset;
+      buf = decode_sleb128 (buf, &offset);
+      state->base_offset = offset;
+      break;
+    case DW_OP_deref:
+      state->indirect = 1;
+      break;
+    case DW_OP_plus_uconst:
+      buf = decode_uleb128 (buf, &offset);
+      state->cfa_offset = offset;
+      break;
+    default:
+      abort ();
+    }
+  return buf;
+}
 /* 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
@@ -567,6 +669,20 @@ execute_cfa_insn (void *p, struct frame_state_internal *state,
       p = decode_uleb128 (p, &offset);
       state->s.cfa_offset = offset;
       break;
+    case DW_CFA_def_cfa_expression:
+      {
+	void *end;
+	state->s.cfa_reg = 0;
+	state->s.cfa_offset = 0;
+	state->s.base_offset = 0;
+	state->s.indirect = 0;
+
+	p = decode_uleb128 (p, &offset);
+	end = p + offset;
+	while (p < end)
+	  p = decode_stack_op (p, &(state->s));
+	break;
+      }
       
     case DW_CFA_remember_state:
       {