readelf: Handle v4 .debug_line format.

diff --git a/src/ChangeLog b/src/ChangeLog
index 3c8c33c..c406208 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2010-06-20  Roland McGrath  <roland@redhat.com>
+
+       * readelf.c (print_debug_line_section): Handle version 4 format.
+
 2010-06-14  Roland McGrath  <roland@redhat.com>
 
        * unstrip.c (copy_elided_sections): Make sure all sections' data have

diff --git a/src/readelf.c b/src/readelf.c
index 1d8da26..514eb00 100644 (file)
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -5559,6 +5559,9 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
       /* Next the minimum instruction length.  */
       uint_fast8_t minimum_instr_len = *linep++;
 
+      /* Next the maximum operations per instruction, in version 4 format.  */
+      uint_fast8_t max_ops_per_instr = version < 4 ? 1 : *linep++;
+
        /* Then the flag determining the default value of the is_stmt
           register.  */
       uint_fast8_t default_is_stmt = *linep++;
@@ -5579,6 +5582,7 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
                       " DWARF version:              %" PRIuFAST16 "\n"
                       " Prologue length:            %" PRIu64 "\n"
                       " Minimum instruction length: %" PRIuFAST8 "\n"
+                      " Maximum operations per instruction: %" PRIuFAST8 "\n"
                       " Initial value if '%s': %" PRIuFAST8 "\n"
                       " Line base:                  %" PRIdFAST8 "\n"
                       " Line range:                 %" PRIuFAST8 "\n"
@@ -5586,7 +5590,8 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
                       "\n"
                       "Opcodes:\n"),
              (uint64_t) unit_length, version, (uint64_t) header_length,
-             minimum_instr_len, "is_stmt", default_is_stmt, line_base,
+             minimum_instr_len, max_ops_per_instr,
+             "is_stmt", default_is_stmt, line_base,
              line_range, opcode_base);
 
       if (unlikely (linep + opcode_base - 1 >= lineendp))
@@ -5663,6 +5668,7 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
 
       puts (gettext ("\nLine number statements:"));
       Dwarf_Word address = 0;
+      unsigned int op_index = 0;
       size_t line = 1;
       uint_fast8_t is_stmt = default_is_stmt;
 
@@ -5694,6 +5700,20 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
            }
        }
 
+      /* Apply the "operation advance" from a special opcode
+        or DW_LNS_advance_pc (as per DWARF4 6.2.5.1).  */
+      unsigned int op_addr_advance;
+      bool show_op_index;
+      inline void advance_pc (unsigned int op_advance)
+      {
+       op_addr_advance = minimum_instr_len * ((op_index + op_advance)
+                                              / max_ops_per_instr);
+       address += op_advance;
+       show_op_index = (op_index > 0 ||
+                        (op_index + op_advance) % max_ops_per_instr > 0);
+       op_index = (op_index + op_advance) % max_ops_per_instr;
+      }
+
       while (linep < lineendp)
        {
          unsigned int u128;
@@ -5713,18 +5733,21 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
              */
              int line_increment = (line_base
                                    + (opcode - opcode_base) % line_range);
-             unsigned int address_increment = (minimum_instr_len
-                                               * ((opcode - opcode_base)
-                                                  / line_range));
 
              /* Perform the increments.  */
              line += line_increment;
-             address += address_increment;
+             advance_pc ((opcode - opcode_base) / line_range);
 
              char *a = format_dwarf_addr (dwflmod, 0, address);
-             printf (gettext ("\
+             if (show_op_index)
+               printf (gettext ("\
+ special opcode %u: address+%u = %s, op_index = %u, line%+d = %zu\n"),
+                       opcode, op_addr_advance, a, op_index,
+                       line_increment, line);
+             else
+               printf (gettext ("\
  special opcode %u: address+%u = %s, line%+d = %zu\n"),
-                     opcode, address_increment, a, line_increment, line);
+                       opcode, op_addr_advance, a, line_increment, line);
              free (a);
            }
          else if (opcode == 0)
@@ -5751,11 +5774,13 @@ print_debug_line_section (Dwfl_Module *dwflmod, Ebl *ebl,
 
                  /* Reset the registers we care about.  */
                  address = 0;
+                 op_index = 0;
                  line = 1;
                  is_stmt = default_is_stmt;
                  break;
 
                case DW_LNE_set_address:
+                 op_index = 0;
                  if (address_size == 4)
                    address = read_4ubyte_unaligned_inc (dbg, linep);
                  else
@@ -5790,6 +5815,15 @@ define new file: dir=%u, mtime=%" PRIu64 ", length=%" PRIu64 ", name=%s\n"),
                  }
                  break;
 
+               case DW_LNE_set_discriminator:
+                 /* Takes one ULEB128 parameter, the discriminator.  */
+                 if (unlikely (standard_opcode_lengths[opcode] != 1))
+                   goto invalid_unit;
+
+                 get_uleb128 (u128, linep);
+                 printf (gettext (" set discriminator to %u\n"), u128);
+                 break;
+
                default:
                  /* Unknown, ignore it.  */
                  puts (gettext ("unknown opcode"));
@@ -5797,7 +5831,7 @@ define new file: dir=%u, mtime=%" PRIu64 ", length=%" PRIu64 ", name=%s\n"),
                  break;
                }
            }
-         else if (opcode <= DW_LNS_set_epilogue_begin)
+         else if (opcode <= DW_LNS_set_isa)
            {
              /* This is a known standard opcode.  */
              switch (opcode)
@@ -5811,11 +5845,16 @@ define new file: dir=%u, mtime=%" PRIu64 ", length=%" PRIu64 ", name=%s\n"),
                  /* Takes one uleb128 parameter which is added to the
                     address.  */
                  get_uleb128 (u128, linep);
-                 address += minimum_instr_len * u128;
+                 advance_pc (u128);
                  {
                    char *a = format_dwarf_addr (dwflmod, 0, address);
-                   printf (gettext ("advance address by %u to %s\n"),
-                           u128, a);
+                   if (show_op_index)
+                     printf (gettext ("\
+advance address by %u to %s, op_index to %u\n"),
+                             op_addr_advance, a, op_index);
+                   else
+                     printf (gettext ("advance address by %u to %s\n"),
+                             op_addr_advance, a);
                    free (a);
                  }
                  break;
@@ -5861,13 +5900,17 @@ define new file: dir=%u, mtime=%" PRIu64 ", length=%" PRIu64 ", name=%s\n"),
 
                case DW_LNS_const_add_pc:
                  /* Takes no argument.  */
-                 u128 = (minimum_instr_len
-                         * ((255 - opcode_base) / line_range));
-                 address += u128;
+                 advance_pc ((255 - opcode_base) / line_range);
                  {
                    char *a = format_dwarf_addr (dwflmod, 0, address);
-                   printf (gettext ("advance address by constant %u to %s\n"),
-                           u128, a);
+                   if (show_op_index)
+                     printf (gettext ("\
+advance address by constant %u to %s, op_index to %u\n"),
+                             op_addr_advance, a, op_index);
+                   else
+                     printf (gettext ("\
+advance address by constant %u to %s\n"),
+                             op_addr_advance, a);
                    free (a);
                  }
                  break;
@@ -5880,6 +5923,7 @@ define new file: dir=%u, mtime=%" PRIu64 ", length=%" PRIu64 ", name=%s\n"),
 
                  u128 = read_2ubyte_unaligned_inc (dbg, linep);
                  address += u128;
+                 op_index = 0;
                  {
                    char *a = format_dwarf_addr (dwflmod, 0, address);
                    printf (gettext ("\
@@ -5898,6 +5942,14 @@ advance address by fixed value %u to %s\n"),
                  /* Takes no argument.  */
                  puts (gettext (" set epilogue begin flag"));
                  break;
+
+               case DW_LNS_set_isa:
+                 /* Takes one uleb128 parameter which is stored in isa.  */
+                 if (unlikely (standard_opcode_lengths[opcode] != 1))
+                   goto invalid_unit;
+
+                 printf (gettext (" set isa to %u\n"), u128);
+                 break;
                }
            }
          else