[RFA/commit] DWARF: Add support for DW_TAG_constant DIEs
Joel Brobecker
brobecker@adacore.com
Thu Sep 16 21:31:00 GMT 2010
Hello,
The GNAT compiler is starting to email DW_TAG_constant dies, so
I needed to add support for this type of tags. It turned out to
be a relatively easy task.
I could have tweaked the psymbol processing to have the block of
code that handles variables also handle constants. But I decided
against it, because I felt that it made the code more complicated
that it needed to, making the handling for variables a little more
complicated (in short, I had to add an code != DW_TAG_constant to
avoid the DIE from being skipped).
Does this look reasonable?
gdb/ChangeLog:
* dwarf2read.c (scan_partial_symbols): Add handling of
DW_TAG_constant DIEs.
(add_partial_symbol, load_partial_dies, new_symbol): Likewise.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-const.S, gdb.dwarf2/dw2-const.exp: New files.
Tested on x86_64-linux. No regression.
Thanks,
--
Joel
---
gdb/dwarf2read.c | 18 +++
gdb/testsuite/gdb.dwarf2/dw2-const.S | 224 ++++++++++++++++++++++++++++++++
gdb/testsuite/gdb.dwarf2/dw2-const.exp | 46 +++++++
3 files changed, 288 insertions(+), 0 deletions(-)
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-const.S
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-const.exp
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 470a3f5..153d8ea 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3467,6 +3467,7 @@ scan_partial_symbols (struct partial_die_info *first_die, CORE_ADDR *lowpc,
case DW_TAG_subprogram:
add_partial_subprogram (pdi, lowpc, highpc, need_pc, cu);
break;
+ case DW_TAG_constant:
case DW_TAG_variable:
case DW_TAG_typedef:
case DW_TAG_union_type:
@@ -3691,6 +3692,20 @@ add_partial_symbol (struct partial_die_info *pdi, struct dwarf2_cu *cu)
cu->language, objfile);
}
break;
+ case DW_TAG_constant:
+ {
+ struct psymbol_allocation_list *list;
+
+ if (pdi->is_external)
+ list = &objfile->global_psymbols;
+ else
+ list = &objfile->global_psymbols;
+ psym = add_psymbol_to_list (actual_name, strlen (actual_name),
+ built_actual_name, VAR_DOMAIN, LOC_STATIC,
+ list, 0, 0, cu->language, objfile);
+
+ }
+ break;
case DW_TAG_variable:
if (pdi->locdesc)
addr = decode_locdesc (pdi->locdesc, cu);
@@ -8568,6 +8583,7 @@ load_partial_dies (bfd *abfd, gdb_byte *buffer, gdb_byte *info_ptr,
static members). */
if (!load_all
&& !is_type_tag_for_partial (abbrev->tag)
+ && abbrev->tag != DW_TAG_constant
&& abbrev->tag != DW_TAG_enumerator
&& abbrev->tag != DW_TAG_subprogram
&& abbrev->tag != DW_TAG_lexical_block
@@ -8678,6 +8694,7 @@ load_partial_dies (bfd *abfd, gdb_byte *buffer, gdb_byte *info_ptr,
unit with load_all_dies set. */
if (load_all
+ || abbrev->tag == DW_TAG_constant
|| abbrev->tag == DW_TAG_subprogram
|| abbrev->tag == DW_TAG_variable
|| abbrev->tag == DW_TAG_namespace
@@ -10584,6 +10601,7 @@ new_symbol_full (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
case DW_TAG_template_value_param:
suppress_add = 1;
/* Fall through. */
+ case DW_TAG_constant:
case DW_TAG_variable:
case DW_TAG_member:
/* Compilation with minimal debug info may result in variables
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-const.S b/gdb/testsuite/gdb.dwarf2/dw2-const.S
new file mode 100644
index 0000000..f5c64f9
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-const.S
@@ -0,0 +1,224 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2010 Free Software Foundation, Inc.
+
+ This program 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 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* Dummy function to provide debug information for. */
+
+ .text
+.Lbegin_text1:
+ .globl func_cu1
+ .type func_cu1, %function
+func_cu1:
+.Lbegin_func_cu1:
+ .int 0
+.Lend_func_cu1:
+ .size func_cu1, .-func_cu1
+.Lend_text1:
+
+/* Debug information */
+
+ .section .debug_info
+.Lcu1_begin:
+ /* CU header */
+ .4byte .Lcu1_end - .Lcu1_start /* Length of Compilation Unit */
+.Lcu1_start:
+ .2byte 2 /* DWARF Version */
+ .4byte .Labbrev1_begin /* Offset into abbrev section */
+ .byte 4 /* Pointer size */
+
+ /* CU die */
+ .uleb128 1 /* Abbrev: DW_TAG_compile_unit */
+ .4byte .Lline1_begin /* DW_AT_stmt_list */
+ .4byte .Lend_text1 /* DW_AT_high_pc */
+ .4byte .Lbegin_text1 /* DW_AT_low_pc */
+ .ascii "file1.txt\0" /* DW_AT_name */
+ .ascii "GNU C 3.3.3\0" /* DW_AT_producer */
+ .byte 1 /* DW_AT_language (C) */
+
+ .uleb128 0x8 /* Abbrev: DW_TAG_constant */
+ .ascii "twelve\0" /* DW_AT_name */
+ .4byte .Ltype_const-.Lcu1_begin /* DW_AT_type */
+ .byte 0xc /* DW_AT_const_value */
+
+.Ltype_const:
+ .uleb128 0x9 /* Abbrev: DW_TAG_const_type */
+ .long .Ltype_int-.Lcu1_begin /* DW_AT_type */
+
+ /* func_cu1 */
+ .uleb128 2 /* Abbrev: DW_TAG_subprogram */
+ .byte 1 /* DW_AT_external */
+ .byte 1 /* DW_AT_decl_file */
+ .byte 2 /* DW_AT_decl_line */
+ .ascii "func_cu1\0" /* DW_AT_name */
+ .4byte .Ltype_int-.Lcu1_begin /* DW_AT_type */
+ .4byte .Lbegin_func_cu1 /* DW_AT_low_pc */
+ .4byte .Lend_func_cu1 /* DW_AT_high_pc */
+ .byte 1 /* DW_AT_frame_base: length */
+ .byte 0x55 /* DW_AT_frame_base: DW_OP_reg5 */
+
+.Ltype_int:
+ .uleb128 3 /* Abbrev: DW_TAG_base_type */
+ .ascii "int\0" /* DW_AT_name */
+ .byte 4 /* DW_AT_byte_size */
+ .byte 5 /* DW_AT_encoding */
+
+ .byte 0 /* End of children of CU */
+
+.Lcu1_end:
+
+/* Abbrev table */
+ .section .debug_abbrev
+.Labbrev1_begin:
+ .uleb128 1 /* Abbrev code */
+ .uleb128 0x11 /* DW_TAG_compile_unit */
+ .byte 1 /* has_children */
+ .uleb128 0x10 /* DW_AT_stmt_list */
+ .uleb128 0x6 /* DW_FORM_data4 */
+ .uleb128 0x12 /* DW_AT_high_pc */
+ .uleb128 0x1 /* DW_FORM_addr */
+ .uleb128 0x11 /* DW_AT_low_pc */
+ .uleb128 0x1 /* DW_FORM_addr */
+ .uleb128 0x3 /* DW_AT_name */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0x25 /* DW_AT_producer */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0x13 /* DW_AT_language */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .uleb128 2 /* Abbrev code */
+ .uleb128 0x2e /* DW_TAG_subprogram */
+ .byte 0 /* has_children */
+ .uleb128 0x3f /* DW_AT_external */
+ .uleb128 0xc /* DW_FORM_flag */
+ .uleb128 0x3a /* DW_AT_decl_file */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .uleb128 0x3b /* DW_AT_decl_line */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .uleb128 0x3 /* DW_AT_name */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0x49 /* DW_AT_type */
+ .uleb128 0x13 /* DW_FORM_ref4 */
+ .uleb128 0x11 /* DW_AT_low_pc */
+ .uleb128 0x1 /* DW_FORM_addr */
+ .uleb128 0x12 /* DW_AT_high_pc */
+ .uleb128 0x1 /* DW_FORM_addr */
+ .uleb128 0x40 /* DW_AT_frame_base */
+ .uleb128 0xa /* DW_FORM_block1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .uleb128 3 /* Abbrev code */
+ .uleb128 0x24 /* DW_TAG_base_type */
+ .byte 0 /* has_children */
+ .uleb128 0x3 /* DW_AT_name */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0xb /* DW_AT_byte_size */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .uleb128 0x3e /* DW_AT_encoding */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .uleb128 0x8 /* abbrev code */
+ .uleb128 0x27 /* TAG: DW_TAG_constant */
+ .byte 0x0 /* DW_children_no */
+ .uleb128 0x3 /* DW_AT_name */
+ .uleb128 0x8 /* DW_FORM_string */
+ .uleb128 0x49 /* DW_AT_type */
+ .uleb128 0x13 /* DW_FORM_ref4 */
+ .uleb128 0x1c /* DW_AT_const_value */
+ .uleb128 0xb /* DW_FORM_data1 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .uleb128 0x9 /* abbrev code */
+ .uleb128 0x26 /* TAG: DW_TAG_const_type */
+ .byte 0x0 /* DW_children_no */
+ .uleb128 0x49 /* DW_AT_type */
+ .uleb128 0x13 /* DW_FORM_ref4 */
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+ .byte 0x0 /* Terminator */
+ .byte 0x0 /* Terminator */
+
+/* Line table */
+ .section .debug_line
+.Lline1_begin:
+ .4byte .Lline1_end - .Lline1_start /* Initial length */
+.Lline1_start:
+ .2byte 2 /* Version */
+ .4byte .Lline1_lines - .Lline1_hdr /* header_length */
+.Lline1_hdr:
+ .byte 1 /* Minimum insn length */
+ .byte 1 /* default_is_stmt */
+ .byte 1 /* line_base */
+ .byte 1 /* line_range */
+ .byte 0x10 /* opcode_base */
+
+ /* Standard lengths */
+ .byte 0
+ .byte 1
+ .byte 1
+ .byte 1
+ .byte 1
+ .byte 0
+ .byte 0
+ .byte 0
+ .byte 1
+ .byte 0
+ .byte 0
+ .byte 1
+ .byte 0
+ .byte 0
+ .byte 0
+
+ /* Include directories */
+ .byte 0
+
+ /* File names */
+ .ascii "file1.txt\0"
+ .uleb128 0
+ .uleb128 0
+ .uleb128 0
+
+ .byte 0
+
+.Lline1_lines:
+ .byte 0 /* DW_LNE_set_address */
+ .uleb128 5
+ .byte 2
+ .4byte .Lbegin_func_cu1
+
+ .byte 3 /* DW_LNS_advance_line */
+ .sleb128 3 /* ... to 4 */
+
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 1 /* DW_LNS_copy (second time as an end-of-prologue marker) */
+
+ .byte 0 /* DW_LNE_set_address */
+ .uleb128 5
+ .byte 2
+ .4byte .Lend_func_cu1
+
+ .byte 0 /* DW_LNE_end_of_sequence */
+ .uleb128 1
+ .byte 1
+
+.Lline1_end:
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-const.exp b/gdb/testsuite/gdb.dwarf2/dw2-const.exp
new file mode 100644
index 0000000..d7bf46f
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-const.exp
@@ -0,0 +1,46 @@
+# Copyright 2010 Free Software Foundation, Inc.
+
+# This program 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 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+# For now pick a sampling of likely targets.
+if {![istarget *-*-linux*]
+ && ![istarget *-*-gnu*]
+ && ![istarget *-*-elf*]
+ && ![istarget *-*-openbsd*]
+ && ![istarget arm-*-eabi*]
+ && ![istarget powerpc-*-eabi*]} {
+ return 0
+}
+
+set testfile "dw2-const"
+set srcfile ${testfile}.S
+set binfile ${objdir}/${subdir}/${testfile}.x
+
+if { [gdb_compile "${srcdir}/${subdir}/main.c" "main.o" object {debug}] != "" } {
+ return -1
+}
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${testfile}.o" object {nodebug}] != "" } {
+ return -1
+}
+
+if { [gdb_compile "${testfile}.o main.o" "${binfile}" executable {debug}] != "" } {
+ return -1
+}
+
+clean_restart ${testfile}.x
+
+gdb_test "print twelve" "= 12"
+
--
1.7.1
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