1 # Copyright 2010-2014 Free Software Foundation, Inc.
3 # This program is free software; you can redistribute it and/or modify
4 # it under the terms of the GNU General Public License as published by
5 # the Free Software Foundation; either version 3 of the License, or
6 # (at your option) any later version.
8 # This program is distributed in the hope that it will be useful,
9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 # GNU General Public License for more details.
13 # You should have received a copy of the GNU General Public License
14 # along with this program. If not, see <http://www.gnu.org/licenses/>.
16 # Return true if the target supports DWARF-2 and uses gas.
17 # For now pick a sampling of likely targets.
18 proc dwarf2_support {} {
19 if {[istarget *-*-linux*]
20 || [istarget *-*-gnu*]
21 || [istarget *-*-elf*]
22 || [istarget *-*-openbsd*]
23 || [istarget arm*-*-eabi*]
24 || [istarget arm*-*-symbianelf*]
25 || [istarget powerpc-*-eabi*]} {
32 # Build an executable from a fission-based .S file.
33 # This handles the extra work of splitting the .o into non-dwo and dwo
34 # pieces, making sure the .dwo is available if we're using cc-with-tweaks.sh
35 # to build a .dwp file.
36 # The arguments and results are the same as for build_executable.
38 # Current restrictions:
39 # - only supports one source file
40 # - cannot be run on remote hosts
42 proc build_executable_from_fission_assembler { testname executable sources options } {
43 verbose -log "build_executable_from_fission_assembler $testname $executable $sources $options"
44 if { [llength $sources] != 1 } {
45 error "Only one source file supported."
48 error "Remote hosts are not supported."
52 set source_file ${srcdir}/${subdir}/${sources}
53 set root_name [file rootname [file tail $source_file]]
54 set output_base [standard_output_file $root_name]
55 set object_file ${output_base}.o
56 set dwo_file ${output_base}.dwo
57 set object_options "object $options"
58 set objcopy [gdb_find_objcopy]
60 set result [gdb_compile $source_file $object_file object $options]
61 if { "$result" != "" } {
65 set command "$objcopy --extract-dwo $object_file $dwo_file"
66 verbose -log "Executing $command"
67 set result [catch "exec $command" output]
68 verbose -log "objcopy --extract-dwo output: $output"
73 set command "$objcopy --strip-dwo $object_file"
74 verbose -log "Executing $command"
75 set result [catch "exec $command" output]
76 verbose -log "objcopy --strip-dwo output: $output"
81 set result [gdb_compile $object_file $executable executable {nodebug}]
82 if { "$result" != "" } {
89 # Return a list of expressions about function FUNC's address and length.
90 # The first expression is the address of function FUNC, and the second
91 # one is FUNC's length. SRC is the source file having function FUNC.
92 # An internal label ${func}_label must be defined inside FUNC:
96 # asm ("main_label: .globl main_label");
100 # This label is needed to compute the start address of function FUNC.
101 # If the compiler is gcc, we can do the following to get function start
102 # and end address too:
104 # asm ("func_start: .globl func_start");
105 # static void func (void) {}
106 # asm ("func_end: .globl func_end");
108 # however, this isn't portable, because other compilers, such as clang,
109 # may not guarantee the order of global asms and function. The code
112 # asm ("func_start: .globl func_start");
113 # asm ("func_end: .globl func_end");
114 # static void func (void) {}
117 proc function_range { func src } {
118 global decimal gdb_prompt
120 set exe [standard_temp_file func_addr[pid].x]
122 gdb_compile $src $exe executable {debug}
128 # Compute the label offset, and we can get the function start address
129 # by "${func}_label - $func_label_offset".
130 set func_label_offset ""
131 set test "p ${func}_label - ${func}"
132 gdb_test_multiple $test $test {
133 -re ".* = ($decimal)\r\n$gdb_prompt $" {
134 set func_label_offset $expect_out(1,string)
138 # Compute the function length.
141 set test "disassemble $func"
142 gdb_test_multiple $test $test {
143 -re ".*$hex <\\+($decimal)>:\[^\r\n\]+\r\nEnd of assembler dump\.\r\n$gdb_prompt $" {
144 set func_length $expect_out(1,string)
148 # Compute the size of the last instruction.
149 set test "x/2i $func+$func_length"
150 gdb_test_multiple $test $test {
151 -re ".*($hex) <$func\\+$func_length>:\[^\r\n\]+\r\n\[ \]+($hex).*\.\r\n$gdb_prompt $" {
152 set start $expect_out(1,string)
153 set end $expect_out(2,string)
155 set func_length [expr $func_length + $end - $start]
159 return [list "${func}_label - $func_label_offset" $func_length]
164 # All the variables in this namespace are private to the
165 # implementation. Also, any procedure whose name starts with "_" is
166 # private as well. Do not use these.
168 # Exported functions are documented at their definition.
170 # In addition to the hand-written functions documented below, this
171 # module automatically generates a function for each DWARF tag. For
172 # most tags, two forms are made: a full name, and one with the
173 # "DW_TAG_" prefix stripped. For example, you can use either
174 # 'DW_TAG_compile_unit' or 'compile_unit' interchangeably.
176 # There are two exceptions to this rule: DW_TAG_variable and
177 # DW_TAG_namespace. For these, the full name must always be used,
178 # as the short name conflicts with Tcl builtins. (Should future
179 # versions of Tcl or DWARF add more conflicts, this list will grow.
180 # If you want to be safe you should always use the full names.)
182 # Each tag procedure is defined like:
184 # proc DW_TAG_mumble {{attrs {}} {children {}}} { ... }
186 # ATTRS is an optional list of attributes.
187 # It is run through 'subst' in the caller's context before processing.
189 # Each attribute in the list has one of two forms:
191 # 2. { NAME VALUE FORM }
193 # In each case, NAME is the attribute's name.
194 # This can either be the full name, like 'DW_AT_name', or a shortened
195 # name, like 'name'. These are fully equivalent.
197 # Besides DWARF standard attributes, assembler supports 'macro' attribute
198 # which will be substituted by one or more standard or macro attributes.
199 # supported macro attributes are:
201 # - MACRO_AT_range { FUNC FILE }
202 # It is substituted by DW_AT_low_pc and DW_AT_high_pc with the start and
203 # end address of function FUNC in file FILE.
205 # - MACRO_AT_func { FUNC FILE }
206 # It is substituted by DW_AT_name with FUNC and MACRO_AT_range.
208 # If FORM is given, it should name a DW_FORM_ constant.
209 # This can either be the short form, like 'DW_FORM_addr', or a
210 # shortened version, like 'addr'. If the form is given, VALUE
211 # is its value; see below. In some cases, additional processing
212 # is done; for example, DW_FORM_strp manages the .debug_str
213 # section automatically.
215 # If FORM is 'SPECIAL_expr', then VALUE is treated as a location
216 # expression. The effective form is then DW_FORM_block, and VALUE
217 # is passed to the (internal) '_location' proc to be translated.
218 # This proc implements a miniature DW_OP_ assembler.
220 # If FORM is not given, it is guessed:
221 # * If VALUE starts with the "@" character, the rest of VALUE is
222 # looked up as a DWARF constant, and DW_FORM_sdata is used. For
223 # example, '@DW_LANG_c89' could be used.
224 # * If VALUE starts with the ":" character, then it is a label
225 # reference. The rest of VALUE is taken to be the name of a label,
226 # and DW_FORM_ref4 is used. See 'new_label' and 'define_label'.
227 # * Otherwise, VALUE is taken to be a string and DW_FORM_string is
229 # More form-guessing functionality may be added.
231 # CHILDREN is just Tcl code that can be used to define child DIEs. It
232 # is evaluated in the caller's context.
234 # Currently this code is missing nice support for CFA handling, and
235 # probably other things as well.
237 namespace eval Dwarf {
238 # True if the module has been initialized.
239 variable _initialized 0
241 # Constants from dwarf2.h.
245 # DW_FORM short names.
250 # The current output file.
251 variable _output_file
253 # Note: The _cu_ values here also apply to type units (TUs).
254 # Think of a TU as a special kind of CU.
259 # The current CU's base label.
262 # The current CU's version.
265 # The current CU's address size.
266 variable _cu_addr_size
267 # The current CU's offset size.
268 variable _cu_offset_size
270 # Label generation number.
273 # The deferred output array. The index is the section name; the
274 # contents hold the data for that section.
275 variable _deferred_output
277 # If empty, we should write directly to the output file.
278 # Otherwise, this is the name of a section to write to.
281 # The abbrev section. Typically .debug_abbrev but can be .debug_abbrev.dwo
283 variable _abbrev_section
285 # The next available abbrev number in the current CU's abbrev
289 # The string table for this assembly. The key is the string; the
290 # value is the label for that string.
293 proc _process_one_constant {name value} {
299 set _constants($name) $value
301 if {![regexp "^DW_(\[A-Z\]+)_(\[A-Za-z0-9_\]+)$" $name \
302 ignore prefix name2]} {
303 error "non-matching name: $name"
306 if {$name2 == "lo_user" || $name2 == "hi_user"} {
310 # We only try to shorten some very common things.
312 switch -exact -- $prefix {
314 # Create two procedures for the tag. These call
315 # _handle_DW_TAG with the full tag name baked in; this
316 # does all the actual work.
317 proc $name {{attrs {}} {children {}}} \
318 "_handle_DW_TAG $name \$attrs \$children"
320 # Filter out ones that are known to clash.
321 if {$name2 == "variable" || $name2 == "namespace"} {
322 set name2 "tag_$name2"
325 if {[info commands $name2] != {}} {
326 error "duplicate proc name: from $name"
329 proc $name2 {{attrs {}} {children {}}} \
330 "_handle_DW_TAG $name \$attrs \$children"
334 set _AT($name2) $name
338 set _FORM($name2) $name
342 set _OP($name2) $name
351 proc _read_constants {} {
352 global srcdir hex decimal
355 # DWARF name-matching regexp.
356 set dwrx "DW_\[a-zA-Z0-9_\]+"
360 set fd [open [file join $srcdir .. .. include dwarf2.h]]
363 if {[regexp -- "^${ws}($dwrx)${ws}=${ws}($hex|$decimal),?$" \
364 $line ignore name value ignore2]} {
365 _process_one_constant $name $value
370 set fd [open [file join $srcdir .. .. include dwarf2.def]]
374 "^DW_\[A-Z_\]+${ws}\\(($dwrx),${ws}($hex|$decimal)\\)$" \
375 $line ignore name value ignore2]} {
376 _process_one_constant $name $value
381 set _constants(SPECIAL_expr) $_constants(DW_FORM_block)
384 proc _quote {string} {
386 return "\"${string}\\0\""
389 proc _nz_quote {string} {
390 # For now, no quoting is done.
391 return "\"${string}\""
394 proc _handle_DW_FORM {form value} {
395 switch -exact -- $form {
397 _op .ascii [_quote $value]
400 DW_FORM_flag_present {
401 # We don't need to emit anything.
410 variable _cu_offset_size
412 variable _cu_addr_size
414 if {$_cu_version == 2} {
415 set size $_cu_addr_size
417 set size $_cu_offset_size
420 _op .${size}byte $value
439 variable _cu_addr_size
441 _op .${_cu_addr_size}byte $value
457 variable _cu_offset_size
459 if {![info exists _strings($value)]} {
460 set _strings($value) [new_label strp]
461 _defer_output .debug_string {
462 define_label $_strings($value)
463 _op .ascii [_quote $value]
467 _op .${_cu_offset_size}byte $_strings($value) "strp: $value"
471 set l1 [new_label "expr_start"]
472 set l2 [new_label "expr_end"]
473 _op .uleb128 "$l2 - $l1" "expression"
480 set len [string length $value]
482 error "DW_FORM_block1 length too long"
485 _op .ascii [_nz_quote $value]
498 DW_FORM_GNU_addr_index -
499 DW_FORM_GNU_str_index -
500 DW_FORM_GNU_ref_alt -
501 DW_FORM_GNU_strp_alt -
504 error "unhandled form $form"
509 proc _guess_form {value varname} {
510 upvar $varname new_value
512 switch -exact -- [string range $value 0 0] {
514 # Constant reference.
517 set new_value $_constants([string range $value 1 end])
526 set new_value "[string range $value 1 end] - $_cu_label"
532 return DW_FORM_string
537 # Map NAME to its canonical form.
538 proc _map_name {name ary} {
541 if {[info exists ${ary}($name)]} {
542 set name [set ${ary}($name)]
548 proc _handle_attribute { attr_name attr_value attr_form } {
549 variable _abbrev_section
552 _handle_DW_FORM $attr_form $attr_value
554 _defer_output $_abbrev_section {
555 _op .uleb128 $_constants($attr_name) $attr_name
556 _op .uleb128 $_constants($attr_form) $attr_form
560 # Handle macro attribute MACRO_AT_range.
562 proc _handle_macro_at_range { attr_value } {
563 if {[llength $attr_value] != 2} {
564 error "usage: MACRO_AT_range { func file }"
567 set func [lindex $attr_value 0]
568 set src [lindex $attr_value 1]
569 set result [function_range $func $src]
571 _handle_attribute DW_AT_low_pc [lindex $result 0] \
573 _handle_attribute DW_AT_high_pc \
574 "[lindex $result 0] + [lindex $result 1]" DW_FORM_addr
577 # Handle macro attribute MACRO_AT_func.
579 proc _handle_macro_at_func { attr_value } {
580 if {[llength $attr_value] != 2} {
581 error "usage: MACRO_AT_func { func file }"
583 _handle_attribute DW_AT_name [lindex $attr_value 0] DW_FORM_string
584 _handle_macro_at_range $attr_value
587 proc _handle_DW_TAG {tag_name {attrs {}} {children {}}} {
588 variable _abbrev_section
592 set has_children [expr {[string length $children] > 0}]
593 set my_abbrev [incr _abbrev_num]
595 # We somewhat wastefully emit a new abbrev entry for each tag.
596 # There's no reason for this other than laziness.
597 _defer_output $_abbrev_section {
598 _op .uleb128 $my_abbrev "Abbrev start"
599 _op .uleb128 $_constants($tag_name) $tag_name
600 _op .byte $has_children "has_children"
603 _op .uleb128 $my_abbrev "Abbrev ($tag_name)"
605 foreach attr $attrs {
606 set attr_name [_map_name [lindex $attr 0] _AT]
607 set attr_value [uplevel 2 [list subst [lindex $attr 1]]]
609 if { [string equal "MACRO_AT_func" $attr_name] } {
610 _handle_macro_at_func $attr_value
611 } elseif { [string equal "MACRO_AT_range" $attr_name] } {
612 _handle_macro_at_range $attr_value
614 if {[llength $attr] > 2} {
615 set attr_form [lindex $attr 2]
617 set attr_form [_guess_form $attr_value attr_value]
619 set attr_form [_map_name $attr_form _FORM]
621 _handle_attribute $attr_name $attr_value $attr_form
625 _defer_output $_abbrev_section {
627 _op .byte 0x0 Terminator
628 _op .byte 0x0 Terminator
634 # Terminate children.
635 _op .byte 0x0 "Terminate children"
639 proc _emit {string} {
640 variable _output_file
642 variable _deferred_output
645 puts $_output_file $string
647 append _deferred_output($_defer) ${string}\n
651 proc _section {name {flags ""} {type ""}} {
652 if {$flags == "" && $type == ""} {
653 _emit " .section $name"
654 } elseif {$type == ""} {
655 _emit " .section $name, \"$flags\""
657 _emit " .section $name, \"$flags\", %$type"
661 # SECTION_SPEC is a list of arguments to _section.
662 proc _defer_output {section_spec body} {
664 variable _deferred_output
666 set old_defer $_defer
667 set _defer [lindex $section_spec 0]
669 if {![info exists _deferred_output($_defer)]} {
670 set _deferred_output($_defer) ""
671 eval _section $section_spec
676 set _defer $old_defer
679 proc _defer_to_string {body} {
681 variable _deferred_output
683 set old_defer $_defer
686 set _deferred_output($_defer) ""
690 set result $_deferred_output($_defer)
691 unset _deferred_output($_defer)
693 set _defer $old_defer
697 proc _write_deferred_output {} {
698 variable _output_file
699 variable _deferred_output
701 foreach section [array names _deferred_output] {
702 # The data already has a newline.
703 puts -nonewline $_output_file $_deferred_output($section)
707 unset _deferred_output
710 proc _op {name value {comment ""}} {
711 set text " ${name} ${value}"
712 if {$comment != ""} {
713 # Try to make stuff line up nicely.
714 while {[string length $text] < 40} {
717 append text "/* ${comment} */"
722 proc _compute_label {name} {
726 # Return a name suitable for use as a label. If BASE_NAME is
727 # specified, it is incorporated into the label name; this is to
728 # make debugging the generated assembler easier. If BASE_NAME is
729 # not specified a generic default is used. This proc does not
730 # define the label; see 'define_label'. 'new_label' attempts to
731 # ensure that label names are unique.
732 proc new_label {{base_name label}} {
735 return [_compute_label ${base_name}[incr _label_num]]
738 # Define a label named NAME. Ordinarily, NAME comes from a call
739 # to 'new_label', but this is not required.
740 proc define_label {name} {
744 # Declare a global label. This is typically used to refer to
745 # labels defined in other files, for example a function defined in
753 # A higher-level interface to label handling.
755 # ARGS is a list of label descriptors. Each one is either a
756 # single element, or a list of two elements -- a name and some
757 # text. For each descriptor, 'new_label' is invoked. If the list
758 # form is used, the second element in the list is passed as an
759 # argument. The label name is used to define a variable in the
760 # enclosing scope; this can be used to refer to the label later.
761 # The label name is also used to define a new proc whose name is
762 # the label name plus a trailing ":". This proc takes a body as
763 # an argument and can be used to define the label at that point;
764 # then the body, if any, is evaluated in the caller's context.
768 # declare_labels int_label
769 # something { ... $int_label } ;# refer to the label
770 # int_label: constant { ... } ;# define the label
771 proc declare_labels {args} {
773 set name [lindex $arg 0]
774 set text [lindex $arg 1]
776 upvar $name label_var
778 set label_var [new_label]
780 set label_var [new_label $text]
783 proc ${name}: {args} [format {
790 # This is a miniature assembler for location expressions. It is
791 # suitable for use in the attributes to a DIE. Its output is
792 # prefixed with "=" to make it automatically use DW_FORM_block.
793 # BODY is split by lines, and each line is taken to be a list.
794 # (FIXME should use 'info complete' here.)
795 # Each list's first element is the opcode, either short or long
796 # forms are accepted.
797 # FIXME argument handling
799 proc _location {body} {
802 variable _cu_addr_size
803 variable _cu_offset_size
805 foreach line [split $body \n] {
806 if {[lindex $line 0] == ""} {
809 set opcode [_map_name [lindex $line 0] _OP]
810 _op .byte $_constants($opcode) $opcode
812 switch -exact -- $opcode {
814 _op .${_cu_addr_size}byte [lindex $line 1]
819 _op .byte [lindex $line 1]
824 _op .2byte [lindex $line 1]
829 _op .4byte [lindex $line 1]
834 _op .8byte [lindex $line 1]
838 _op .uleb128 [lindex $line 1]
841 _op .sleb128 [lindex $line 1]
845 _op .uleb128 [lindex $line 1]
849 _op .uleb128 [lindex $line 1]
853 _op .uleb128 [lindex $line 1]
854 _op .uleb128 [lindex $line 2]
857 DW_OP_GNU_implicit_pointer {
858 if {[llength $line] != 3} {
859 error "usage: DW_OP_GNU_implicit_pointer LABEL OFFSET"
862 # Here label is a section offset.
863 set label [lindex $line 1]
864 _op .${_cu_offset_size}byte $label
865 _op .sleb128 [lindex $line 2]
869 if {[llength $line] != 2} {
870 error "usage: DW_OP_deref_size SIZE"
873 _op .byte [lindex $line 1]
877 if {[llength $line] > 1} {
878 error "Unimplemented: operands in location for $opcode"
886 # OPTIONS is a list with an even number of elements containing
887 # option-name and option-value pairs.
888 # Current options are:
889 # is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
890 # default = 0 (32-bit)
891 # version n - DWARF version number to emit
893 # addr_size n - the size of addresses, 32, 64, or default
895 # fission 0|1 - boolean indicating if generating Fission debug info
897 # BODY is Tcl code that emits the DIEs which make up the body of
898 # the CU. It is evaluated in the caller's context.
899 proc cu {options body} {
901 variable _abbrev_section
905 variable _cu_addr_size
906 variable _cu_offset_size
908 # Establish the defaults.
911 set _cu_addr_size default
913 set section ".debug_info"
914 set _abbrev_section ".debug_abbrev"
916 foreach { name value } $options {
917 switch -exact -- $name {
918 is_64 { set is_64 $value }
919 version { set _cu_version $value }
920 addr_size { set _cu_addr_size $value }
921 fission { set fission $value }
922 default { error "unknown option $name" }
925 if {$_cu_addr_size == "default"} {
926 if {[is_64_target]} {
932 set _cu_offset_size [expr { $is_64 ? 8 : 4 }]
934 set section ".debug_info.dwo"
935 set _abbrev_section ".debug_abbrev.dwo"
940 set cu_num [incr _cu_count]
941 set my_abbrevs [_compute_label "abbrev${cu_num}_begin"]
944 set _cu_label [_compute_label "cu${cu_num}_begin"]
945 set start_label [_compute_label "cu${cu_num}_start"]
946 set end_label [_compute_label "cu${cu_num}_end"]
948 define_label $_cu_label
950 _op .4byte 0xffffffff
951 _op .8byte "$end_label - $start_label"
953 _op .4byte "$end_label - $start_label"
955 define_label $start_label
956 _op .2byte $_cu_version Version
957 _op .${_cu_offset_size}byte $my_abbrevs Abbrevs
958 _op .byte $_cu_addr_size "Pointer size"
960 _defer_output $_abbrev_section {
961 define_label $my_abbrevs
966 _defer_output $_abbrev_section {
967 # Emit the terminator.
968 _op .byte 0x0 Terminator
969 _op .byte 0x0 Terminator
972 define_label $end_label
976 # OPTIONS is a list with an even number of elements containing
977 # option-name and option-value pairs.
978 # Current options are:
979 # is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
980 # default = 0 (32-bit)
981 # version n - DWARF version number to emit
983 # addr_size n - the size of addresses, 32, 64, or default
985 # fission 0|1 - boolean indicating if generating Fission debug info
987 # SIGNATURE is the 64-bit signature of the type.
988 # TYPE_LABEL is the label of the type defined by this TU,
989 # or "" if there is no type (i.e., type stubs in Fission).
990 # BODY is Tcl code that emits the DIEs which make up the body of
991 # the TU. It is evaluated in the caller's context.
992 proc tu {options signature type_label body} {
994 variable _abbrev_section
998 variable _cu_addr_size
999 variable _cu_offset_size
1001 # Establish the defaults.
1004 set _cu_addr_size default
1006 set section ".debug_types"
1007 set _abbrev_section ".debug_abbrev"
1009 foreach { name value } $options {
1010 switch -exact -- $name {
1011 is_64 { set is_64 $value }
1012 version { set _cu_version $value }
1013 addr_size { set _cu_addr_size $value }
1014 fission { set fission $value }
1015 default { error "unknown option $name" }
1018 if {$_cu_addr_size == "default"} {
1019 if {[is_64_target]} {
1025 set _cu_offset_size [expr { $is_64 ? 8 : 4 }]
1027 set section ".debug_types.dwo"
1028 set _abbrev_section ".debug_abbrev.dwo"
1033 set cu_num [incr _cu_count]
1034 set my_abbrevs [_compute_label "abbrev${cu_num}_begin"]
1037 set _cu_label [_compute_label "cu${cu_num}_begin"]
1038 set start_label [_compute_label "cu${cu_num}_start"]
1039 set end_label [_compute_label "cu${cu_num}_end"]
1041 define_label $_cu_label
1043 _op .4byte 0xffffffff
1044 _op .8byte "$end_label - $start_label"
1046 _op .4byte "$end_label - $start_label"
1048 define_label $start_label
1049 _op .2byte $_cu_version Version
1050 _op .${_cu_offset_size}byte $my_abbrevs Abbrevs
1051 _op .byte $_cu_addr_size "Pointer size"
1052 _op .8byte $signature Signature
1053 if { $type_label != "" } {
1054 uplevel declare_labels $type_label
1055 upvar $type_label my_type_label
1057 _op .8byte "$my_type_label - $_cu_label"
1059 _op .4byte "$my_type_label - $_cu_label"
1069 _defer_output $_abbrev_section {
1070 define_label $my_abbrevs
1075 _defer_output $_abbrev_section {
1076 # Emit the terminator.
1077 _op .byte 0x0 Terminator
1078 _op .byte 0x0 Terminator
1081 define_label $end_label
1084 proc _empty_array {name} {
1085 upvar $name the_array
1087 catch {unset the_array}
1092 # Emit a .gnu_debugaltlink section with the given file name and
1093 # build-id. The buildid should be represented as a hexadecimal
1094 # string, like "ffeeddcc".
1095 proc gnu_debugaltlink {filename buildid} {
1096 _defer_output .gnu_debugaltlink {
1097 _op .ascii [_quote $filename]
1098 foreach {a b} [split $buildid {}] {
1104 proc _note {type name hexdata} {
1105 set namelen [expr [string length $name] + 1]
1110 _op .4byte [expr [string length $hexdata] / 2]
1114 _op .ascii [_quote $name]
1117 set total [expr {($namelen + (1 << $align) - 1) & (-1 << $align)}]
1118 for {set i $namelen} {$i < $total} {incr i} {
1122 foreach {a b} [split $hexdata {}] {
1127 # Emit a note section holding the given build-id.
1128 proc build_id {buildid} {
1129 _defer_output {.note.gnu.build-id a note} {
1130 # From elf/common.h.
1131 set NT_GNU_BUILD_ID 3
1133 _note $NT_GNU_BUILD_ID GNU $buildid
1137 # The top-level interface to the DWARF assembler.
1138 # FILENAME is the name of the file where the generated assembly
1140 # BODY is Tcl code to emit the assembly. It is evaluated via
1141 # "eval" -- not uplevel as you might expect, because it is
1142 # important to run the body in the Dwarf namespace.
1144 # A typical invocation is something like:
1145 # Dwarf::assemble $file {
1155 proc assemble {filename body} {
1156 variable _initialized
1157 variable _output_file
1158 variable _deferred_output
1164 if {!$_initialized} {
1169 set _output_file [open $filename w]
1171 _empty_array _deferred_output
1174 _empty_array _strings
1176 # Not "uplevel" here, because we want to evaluate in this
1177 # namespace. This is somewhat bad because it means we can't
1178 # readily refer to outer variables.
1181 _write_deferred_output
1183 catch {close $_output_file}