blob: 3bb9bdbd3d4940c5369874e1891b1b440d91b5c6 [file] [log] [blame]
# Copyright 2010-2021 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/>.
# Return true if the target supports DWARF-2 and uses gas.
# For now pick a sampling of likely targets.
proc dwarf2_support {} {
if {[istarget *-*-linux*]
|| [istarget *-*-gnu*]
|| [istarget *-*-elf*]
|| [istarget *-*-openbsd*]
|| [istarget arm*-*-eabi*]
|| [istarget powerpc-*-eabi*]} {
return 1
}
return 0
}
# Use 'objcopy --extract-dwo to extract DWO information from
# OBJECT_FILE and place it into DWO_FILE.
#
# Return 0 on success, otherwise, return -1.
proc extract_dwo_information { object_file dwo_file } {
set objcopy [gdb_find_objcopy]
set command "$objcopy --extract-dwo $object_file $dwo_file"
verbose -log "Executing $command"
set result [catch "exec $command" output]
verbose -log "objcopy --extract-dwo output: $output"
if { $result == 1 } {
return -1
}
return 0
}
# Use 'objcopy --strip-dwo to remove DWO information from
# FILENAME.
#
# Return 0 on success, otherwise, return -1.
proc strip_dwo_information { filename } {
set objcopy [gdb_find_objcopy]
set command "$objcopy --strip-dwo $filename"
verbose -log "Executing $command"
set result [catch "exec $command" output]
verbose -log "objcopy --strip-dwo output: $output"
if { $result == 1 } {
return -1
}
return 0
}
# Build an executable, with the debug information split out into a
# separate .dwo file.
#
# This function is based on build_executable_from_specs in
# lib/gdb.exp, but with threading support, and rust support removed.
#
# TESTNAME is the name of the test; this is passed to 'untested' if
# something fails.
#
# EXECUTABLE is the executable to create, this can be an absolute
# path, or a relative path, in which case the EXECUTABLE will be
# created in the standard output directory.
#
# OPTIONS is passed to the final link, using gdb_compile. If OPTIONS
# contains any option that indicates threads is required, of if the
# option rust is included, then this function will return failure.
#
# ARGS is a series of lists. Each list is a spec for one source file
# that will be compiled to make EXECUTABLE. Each spec in ARGS has the
# form:
# [ SOURCE OPTIONS ]
# or:
# [ SOURCE OPTIONS OBJFILE ]
#
# Where SOURCE is the path to the source file to compile. This can be
# absolute, or relative to the standard global ${subdir}/${srcdir}/
# path.
#
# OPTIONS are the options to use when compiling SOURCE into an object
# file.
#
# OBJFILE is optional, if present this is the name of the object file
# to create for SOURCE. If this is not provided then a suitable name
# will be auto-generated.
#
# If OPTIONS contains the option 'split-dwo' then the debug
# information is extracted from the object file created by compiling
# SOURCE and placed into a file with a dwo extension. The name of
# this file is generated based on the name of the object file that was
# created (with the .o replaced with .dwo).
proc build_executable_and_dwo_files { testname executable options args } {
global subdir
global srcdir
if { ! [regexp "^/" "$executable"] } then {
set binfile [standard_output_file $executable]
} else {
set binfile $executable
}
set info_options ""
if { [lsearch -exact $options "c++"] >= 0 } {
set info_options "c++"
}
if [get_compiler_info ${info_options}] {
return -1
}
set func gdb_compile
if {[lsearch -regexp $options \
{^(pthreads|shlib|shlib_pthreads|openmp)$}] != -1} {
# Currently don't support compiling thread based tests here.
# If this is required then look to build_executable_from_specs
# for inspiration.
return -1
}
if {[lsearch -exact $options rust] != -1} {
# Currently don't support compiling rust tests here. If this
# is required then look to build_executable_from_specs for
# inspiration.
return -1
}
# Must be run on local host due to use of objcopy.
if [is_remote host] {
return -1
}
set objects {}
set i 0
foreach spec $args {
if {[llength $spec] < 2} {
error "invalid spec length"
return -1
}
verbose -log "APB: SPEC: $spec"
set s [lindex $spec 0]
set local_options [lindex $spec 1]
if { ! [regexp "^/" "$s"] } then {
set s "$srcdir/$subdir/$s"
}
if {[llength $spec] > 2} {
set objfile [lindex $spec 2]
} else {
set objfile "${binfile}${i}.o"
incr i
}
if { [$func "${s}" "${objfile}" object $local_options] != "" } {
untested $testname
return -1
}
lappend objects "$objfile"
if {[lsearch -exact $local_options "split-dwo"] >= 0} {
# Split out the DWO file.
set dwo_file "[file rootname ${objfile}].dwo"
if { [extract_dwo_information $objfile $dwo_file] == -1 } {
untested $testname
return -1
}
if { [strip_dwo_information $objfile] == -1 } {
untested $testname
return -1
}
}
}
verbose -log "APB: OBJECTS = $objects"
set ret [$func $objects "${binfile}" executable $options]
if { $ret != "" } {
untested $testname
return -1
}
return 0
}
# Return a list of expressions about function FUNC's address and length.
# The first expression is the address of function FUNC, and the second
# one is FUNC's length. SRC is the source file having function FUNC.
# An internal label ${func}_label must be defined inside FUNC:
#
# int main (void)
# {
# asm ("main_label: .globl main_label");
# return 0;
# }
#
# This label is needed to compute the start address of function FUNC.
# If the compiler is gcc, we can do the following to get function start
# and end address too:
#
# asm ("func_start: .globl func_start");
# static void func (void) {}
# asm ("func_end: .globl func_end");
#
# however, this isn't portable, because other compilers, such as clang,
# may not guarantee the order of global asms and function. The code
# becomes:
#
# asm ("func_start: .globl func_start");
# asm ("func_end: .globl func_end");
# static void func (void) {}
#
proc function_range { func src {options {debug}} } {
global decimal gdb_prompt
set exe [standard_temp_file func_addr[pid].x]
gdb_compile $src $exe executable $options
gdb_exit
gdb_start
gdb_load "$exe"
# Compute the label offset, and we can get the function start address
# by "${func}_label - $func_label_offset".
set func_label_offset ""
set test "p ${func}_label - ${func}"
gdb_test_multiple $test $test {
-re ".* = ($decimal)\r\n$gdb_prompt $" {
set func_label_offset $expect_out(1,string)
}
}
# Compute the function length.
global hex
set func_length ""
set test "disassemble $func"
gdb_test_multiple $test $test {
-re ".*$hex <\\+($decimal)>:\[^\r\n\]+\r\nEnd of assembler dump\.\r\n$gdb_prompt $" {
set func_length $expect_out(1,string)
}
}
# Compute the size of the last instruction.
if { $func_length == 0 } then {
set func_pattern "$func"
} else {
set func_pattern "$func\\+$func_length"
}
set test "x/2i $func+$func_length"
gdb_test_multiple $test $test {
-re ".*($hex) <$func_pattern>:\[^\r\n\]+\r\n\[ \]+($hex).*\.\r\n$gdb_prompt $" {
set start $expect_out(1,string)
set end $expect_out(2,string)
set func_length [expr $func_length + $end - $start]
}
}
gdb_exit
return [list "${func}_label - $func_label_offset" $func_length]
}
# Extract the start, length, and end for function called NAME and
# create suitable variables in the callers scope.
proc get_func_info { name {options {debug}} } {
global srcdir subdir srcfile
upvar 1 "${name}_start" func_start
upvar 1 "${name}_len" func_len
upvar 1 "${name}_end" func_end
lassign [function_range ${name} \
[list ${srcdir}/${subdir}/$srcfile] \
${options}] \
func_start func_len
set func_end "$func_start + $func_len"
}
# A DWARF assembler.
#
# All the variables in this namespace are private to the
# implementation. Also, any procedure whose name starts with "_" is
# private as well. Do not use these.
#
# Exported functions are documented at their definition.
#
# In addition to the hand-written functions documented below, this
# module automatically generates a function for each DWARF tag. For
# most tags, two forms are made: a full name, and one with the
# "DW_TAG_" prefix stripped. For example, you can use either
# 'DW_TAG_compile_unit' or 'compile_unit' interchangeably.
#
# There are two exceptions to this rule: DW_TAG_variable and
# DW_TAG_namespace. For these, the full name must always be used,
# as the short name conflicts with Tcl builtins. (Should future
# versions of Tcl or DWARF add more conflicts, this list will grow.
# If you want to be safe you should always use the full names.)
#
# Each tag procedure is defined like:
#
# proc DW_TAG_mumble {{attrs {}} {children {}}} { ... }
#
# ATTRS is an optional list of attributes.
# It is run through 'subst' in the caller's context before processing.
#
# Each attribute in the list has one of two forms:
# 1. { NAME VALUE }
# 2. { NAME VALUE FORM }
#
# In each case, NAME is the attribute's name.
# This can either be the full name, like 'DW_AT_name', or a shortened
# name, like 'name'. These are fully equivalent.
#
# Besides DWARF standard attributes, assembler supports 'macro' attribute
# which will be substituted by one or more standard or macro attributes.
# supported macro attributes are:
#
# - MACRO_AT_range { FUNC }
# It is substituted by DW_AT_low_pc and DW_AT_high_pc with the start and
# end address of function FUNC in file $srcdir/$subdir/$srcfile.
#
# - MACRO_AT_func { FUNC }
# It is substituted by DW_AT_name with FUNC and MACRO_AT_range.
#
# If FORM is given, it should name a DW_FORM_ constant.
# This can either be the short form, like 'DW_FORM_addr', or a
# shortened version, like 'addr'. If the form is given, VALUE
# is its value; see below. In some cases, additional processing
# is done; for example, DW_FORM_strp manages the .debug_str
# section automatically.
#
# If FORM is 'SPECIAL_expr', then VALUE is treated as a location
# expression. The effective form is then DW_FORM_block or DW_FORM_exprloc
# for DWARF version >= 4, and VALUE is passed to the (internal)
# '_location' proc to be translated.
# This proc implements a miniature DW_OP_ assembler.
#
# If FORM is not given, it is guessed:
# * If VALUE starts with the "@" character, the rest of VALUE is
# looked up as a DWARF constant, and DW_FORM_sdata is used. For
# example, '@DW_LANG_c89' could be used.
# * If VALUE starts with the ":" character, then it is a label
# reference. The rest of VALUE is taken to be the name of a label,
# and DW_FORM_ref4 is used. See 'new_label' and 'define_label'.
# * If VALUE starts with the "%" character, then it is a label
# reference too, but DW_FORM_ref_addr is used.
# * Otherwise, if the attribute name has a default form (f.i. DW_FORM_addr for
# DW_AT_low_pc), then that one is used.
# * Otherwise, an error is reported. Either specify a form explicitly, or
# add a default for the the attribute name in _default_form.
#
# CHILDREN is just Tcl code that can be used to define child DIEs. It
# is evaluated in the caller's context.
#
# Currently this code is missing nice support for CFA handling, and
# probably other things as well.
namespace eval Dwarf {
# True if the module has been initialized.
variable _initialized 0
# Constants from dwarf2.h.
variable _constants
# DW_AT short names.
variable _AT
# DW_FORM short names.
variable _FORM
# DW_OP short names.
variable _OP
# The current output file.
variable _output_file
# Note: The _cu_ values here also apply to type units (TUs).
# Think of a TU as a special kind of CU.
# Current CU count.
variable _cu_count
# The current CU's base label.
variable _cu_label
# The current CU's version.
variable _cu_version
# The current CU's address size.
variable _cu_addr_size
# The current CU's offset size.
variable _cu_offset_size
# Label generation number.
variable _label_num
# The deferred output array. The index is the section name; the
# contents hold the data for that section.
variable _deferred_output
# If empty, we should write directly to the output file.
# Otherwise, this is the name of a section to write to.
variable _defer
# The abbrev section. Typically .debug_abbrev but can be .debug_abbrev.dwo
# for Fission.
variable _abbrev_section
# The next available abbrev number in the current CU's abbrev
# table.
variable _abbrev_num
# The string table for this assembly. The key is the string; the
# value is the label for that string.
variable _strings
# Current .debug_line unit count.
variable _line_count
# Whether a file_name entry was seen.
variable _line_saw_file
# Whether a line table program has been seen.
variable _line_saw_program
# A Label for line table header generation.
variable _line_header_end_label
# The address size for debug ranges section.
variable _debug_ranges_64_bit
# The index into the .debug_addr section (used for fission
# generation).
variable _debug_addr_index
# Flag, true if the current CU is contains fission information,
# otherwise false.
variable _cu_is_fission
proc _process_one_constant {name value} {
variable _constants
variable _AT
variable _FORM
variable _OP
set _constants($name) $value
if {![regexp "^DW_(\[A-Z\]+)_(\[A-Za-z0-9_\]+)$" $name \
ignore prefix name2]} {
error "non-matching name: $name"
}
if {$name2 == "lo_user" || $name2 == "hi_user"} {
return
}
# We only try to shorten some very common things.
# FIXME: CFA?
switch -exact -- $prefix {
TAG {
# Create two procedures for the tag. These call
# _handle_DW_TAG with the full tag name baked in; this
# does all the actual work.
proc $name {{attrs {}} {children {}}} \
"_handle_DW_TAG $name \$attrs \$children"
# Filter out ones that are known to clash.
if {$name2 == "variable" || $name2 == "namespace"} {
set name2 "tag_$name2"
}
if {[info commands $name2] != {}} {
error "duplicate proc name: from $name"
}
proc $name2 {{attrs {}} {children {}}} \
"_handle_DW_TAG $name \$attrs \$children"
}
AT {
set _AT($name2) $name
}
FORM {
set _FORM($name2) $name
}
OP {
set _OP($name2) $name
}
default {
return
}
}
}
proc _read_constants {} {
global srcdir hex decimal
# DWARF name-matching regexp.
set dwrx "DW_\[a-zA-Z0-9_\]+"
# Whitespace regexp.
set ws "\[ \t\]+"
set fd [open [file join $srcdir .. .. include dwarf2.h]]
while {![eof $fd]} {
set line [gets $fd]
if {[regexp -- "^${ws}($dwrx)${ws}=${ws}($hex|$decimal),?$" \
$line ignore name value ignore2]} {
_process_one_constant $name $value
}
}
close $fd
set fd [open [file join $srcdir .. .. include dwarf2.def]]
while {![eof $fd]} {
set line [gets $fd]
if {[regexp -- \
"^DW_\[A-Z_\]+${ws}\\(($dwrx),${ws}($hex|$decimal)\\)$" \
$line ignore name value ignore2]} {
_process_one_constant $name $value
}
}
close $fd
}
proc _quote {string} {
# FIXME
return "\"${string}\\0\""
}
proc _nz_quote {string} {
# For now, no quoting is done.
return "\"${string}\""
}
proc _handle_DW_FORM {form value} {
switch -exact -- $form {
DW_FORM_string {
_op .ascii [_quote $value]
}
DW_FORM_flag_present {
# We don't need to emit anything.
}
DW_FORM_data4 -
DW_FORM_ref4 {
_op .4byte $value
}
DW_FORM_ref_addr {
variable _cu_offset_size
variable _cu_version
variable _cu_addr_size
if {$_cu_version == 2} {
set size $_cu_addr_size
} else {
set size $_cu_offset_size
}
_op .${size}byte $value
}
DW_FORM_GNU_ref_alt -
DW_FORM_GNU_strp_alt -
DW_FORM_sec_offset {
variable _cu_offset_size
_op .${_cu_offset_size}byte $value
}
DW_FORM_ref1 -
DW_FORM_flag -
DW_FORM_data1 {
_op .byte $value
}
DW_FORM_sdata {
_op .sleb128 $value
}
DW_FORM_ref_udata -
DW_FORM_udata -
DW_FORM_loclistx -
DW_FORM_rnglistx {
_op .uleb128 $value
}
DW_FORM_addr {
variable _cu_addr_size
_op .${_cu_addr_size}byte $value
}
DW_FORM_GNU_addr_index {
variable _debug_addr_index
variable _cu_addr_size
_op .uleb128 ${_debug_addr_index}
incr _debug_addr_index
_defer_output .debug_addr {
_op .${_cu_addr_size}byte $value
}
}
DW_FORM_data2 -
DW_FORM_ref2 {
_op .2byte $value
}
DW_FORM_data8 -
DW_FORM_ref8 -
DW_FORM_ref_sig8 {
_op .8byte $value
}
DW_FORM_data16 {
_op .8byte $value
}
DW_FORM_strp {
variable _strings
variable _cu_offset_size
if {![info exists _strings($value)]} {
set _strings($value) [new_label strp]
_defer_output .debug_str {
define_label $_strings($value)
_op .ascii [_quote $value]
}
}
_op .${_cu_offset_size}byte $_strings($value) "strp: $value"
}
SPECIAL_expr {
variable _cu_version
variable _cu_addr_size
variable _cu_offset_size
set l1 [new_label "expr_start"]
set l2 [new_label "expr_end"]
_op .uleb128 "$l2 - $l1" "expression"
define_label $l1
_location $value $_cu_version $_cu_addr_size $_cu_offset_size
define_label $l2
}
DW_FORM_block1 {
set len [string length $value]
if {$len > 255} {
error "DW_FORM_block1 length too long"
}
_op .byte $len
_op .ascii [_nz_quote $value]
}
DW_FORM_block2 -
DW_FORM_block4 -
DW_FORM_block -
DW_FORM_ref2 -
DW_FORM_indirect -
DW_FORM_exprloc -
DW_FORM_strx -
DW_FORM_strx1 -
DW_FORM_strx2 -
DW_FORM_strx3 -
DW_FORM_strx4 -
DW_FORM_GNU_str_index -
default {
error "unhandled form $form"
}
}
}
proc _guess_form {value varname} {
upvar $varname new_value
switch -exact -- [string range $value 0 0] {
@ {
# Constant reference.
variable _constants
set new_value $_constants([string range $value 1 end])
# Just the simplest.
return DW_FORM_sdata
}
: {
# Label reference.
variable _cu_label
set new_value "[string range $value 1 end] - $_cu_label"
return DW_FORM_ref4
}
% {
# Label reference, an offset from .debug_info.
set new_value "[string range $value 1 end]"
return DW_FORM_ref_addr
}
default {
return ""
}
}
}
proc _default_form { attr } {
switch -exact -- $attr {
DW_AT_low_pc {
return DW_FORM_addr
}
DW_AT_producer -
DW_AT_comp_dir -
DW_AT_linkage_name -
DW_AT_MIPS_linkage_name -
DW_AT_name {
return DW_FORM_string
}
DW_AT_GNU_addr_base {
return DW_FORM_sec_offset
}
}
return ""
}
# Map NAME to its canonical form.
proc _map_name {name ary} {
variable $ary
if {[info exists ${ary}($name)]} {
set name [set ${ary}($name)]
}
return $name
}
proc _handle_attribute { attr_name attr_value attr_form } {
variable _abbrev_section
variable _constants
variable _cu_version
_handle_DW_FORM $attr_form $attr_value
_defer_output $_abbrev_section {
if { $attr_form eq "SPECIAL_expr" } {
if { $_cu_version < 4 } {
set attr_form_comment "DW_FORM_block"
} else {
set attr_form_comment "DW_FORM_exprloc"
}
} else {
set attr_form_comment $attr_form
}
_op .uleb128 $_constants($attr_name) $attr_name
_op .uleb128 $_constants($attr_form) $attr_form_comment
}
}
# Handle macro attribute MACRO_AT_range.
proc _handle_macro_at_range { attr_value } {
variable _cu_is_fission
if {[llength $attr_value] != 1} {
error "usage: MACRO_AT_range { func }"
}
set func [lindex $attr_value 0]
global srcdir subdir srcfile
set src ${srcdir}/${subdir}/${srcfile}
set result [function_range $func $src]
set form DW_FORM_addr
if { $_cu_is_fission } {
set form DW_FORM_GNU_addr_index
}
_handle_attribute DW_AT_low_pc [lindex $result 0] $form
_handle_attribute DW_AT_high_pc \
"[lindex $result 0] + [lindex $result 1]" $form
}
# Handle macro attribute MACRO_AT_func.
proc _handle_macro_at_func { attr_value } {
if {[llength $attr_value] != 1} {
error "usage: MACRO_AT_func { func file }"
}
_handle_attribute DW_AT_name [lindex $attr_value 0] DW_FORM_string
_handle_macro_at_range $attr_value
}
proc _handle_DW_TAG {tag_name {attrs {}} {children {}}} {
variable _abbrev_section
variable _abbrev_num
variable _constants
set has_children [expr {[string length $children] > 0}]
set my_abbrev [incr _abbrev_num]
# We somewhat wastefully emit a new abbrev entry for each tag.
# There's no reason for this other than laziness.
_defer_output $_abbrev_section {
_op .uleb128 $my_abbrev "Abbrev start"
_op .uleb128 $_constants($tag_name) $tag_name
_op .byte $has_children "has_children"
}
_op .uleb128 $my_abbrev "Abbrev ($tag_name)"
foreach attr $attrs {
set attr_name [_map_name [lindex $attr 0] _AT]
# When the length of ATTR is greater than 2, the last
# element of the list must be a form. The second through
# the penultimate elements are joined together and
# evaluated using subst. This allows constructs such as
# [gdb_target_symbol foo] to be used.
if {[llength $attr] > 2} {
set attr_value [uplevel 2 [list subst [join [lrange $attr 1 end-1]]]]
} else {
set attr_value [uplevel 2 [list subst [lindex $attr 1]]]
}
if { [string equal "MACRO_AT_func" $attr_name] } {
_handle_macro_at_func $attr_value
} elseif { [string equal "MACRO_AT_range" $attr_name] } {
_handle_macro_at_range $attr_value
} else {
if {[llength $attr] > 2} {
set attr_form [uplevel 2 [list subst [lindex $attr end]]]
if { [string index $attr_value 0] == ":" } {
# It is a label, get its value.
_guess_form $attr_value attr_value
}
} else {
set attr_form [_guess_form $attr_value attr_value]
if { $attr_form eq "" } {
set attr_form [_default_form $attr_name]
}
if { $attr_form eq "" } {
error "No form for $attr_name $attr_value"
}
}
set attr_form [_map_name $attr_form _FORM]
_handle_attribute $attr_name $attr_value $attr_form
}
}
_defer_output $_abbrev_section {
# Terminator.
_op .byte 0x0 "DW_AT - Terminator"
_op .byte 0x0 "DW_FORM - Terminator"
}
if {$has_children} {
uplevel 2 $children
# Terminate children.
_op .byte 0x0 "Terminate children"
}
}
proc _emit {string} {
variable _output_file
variable _defer
variable _deferred_output
if {$_defer == ""} {
puts $_output_file $string
} else {
append _deferred_output($_defer) ${string}\n
}
}
proc _section {name {flags ""} {type ""}} {
if {$flags == "" && $type == ""} {
_emit " .section $name"
} elseif {$type == ""} {
_emit " .section $name, \"$flags\""
} else {
_emit " .section $name, \"$flags\", %$type"
}
}
# SECTION_SPEC is a list of arguments to _section.
proc _defer_output {section_spec body} {
variable _defer
variable _deferred_output
set old_defer $_defer
set _defer [lindex $section_spec 0]
if {![info exists _deferred_output($_defer)]} {
set _deferred_output($_defer) ""
eval _section $section_spec
}
uplevel $body
set _defer $old_defer
}
proc _defer_to_string {body} {
variable _defer
variable _deferred_output
set old_defer $_defer
set _defer temp
set _deferred_output($_defer) ""
uplevel $body
set result $_deferred_output($_defer)
unset _deferred_output($_defer)
set _defer $old_defer
return $result
}
proc _write_deferred_output {} {
variable _output_file
variable _deferred_output
foreach section [array names _deferred_output] {
# The data already has a newline.
puts -nonewline $_output_file $_deferred_output($section)
}
# Save some memory.
unset _deferred_output
}
proc _op {name value {comment ""}} {
set text " ${name} ${value}"
if {$comment != ""} {
# Try to make stuff line up nicely.
while {[string length $text] < 40} {
append text " "
}
append text "/* ${comment} */"
}
_emit $text
}
proc _compute_label {name} {
return ".L${name}"
}
# Return a name suitable for use as a label. If BASE_NAME is
# specified, it is incorporated into the label name; this is to
# make debugging the generated assembler easier. If BASE_NAME is
# not specified a generic default is used. This proc does not
# define the label; see 'define_label'. 'new_label' attempts to
# ensure that label names are unique.
proc new_label {{base_name label}} {
variable _label_num
return [_compute_label ${base_name}[incr _label_num]]
}
# Define a label named NAME. Ordinarily, NAME comes from a call
# to 'new_label', but this is not required.
proc define_label {name} {
_emit "${name}:"
}
# A higher-level interface to label handling.
#
# ARGS is a list of label descriptors. Each one is either a
# single element, or a list of two elements -- a name and some
# text. For each descriptor, 'new_label' is invoked. If the list
# form is used, the second element in the list is passed as an
# argument. The label name is used to define a variable in the
# enclosing scope; this can be used to refer to the label later.
# The label name is also used to define a new proc whose name is
# the label name plus a trailing ":". This proc takes a body as
# an argument and can be used to define the label at that point;
# then the body, if any, is evaluated in the caller's context.
#
# For example:
#
# declare_labels int_label
# something { ... $int_label } ;# refer to the label
# int_label: constant { ... } ;# define the label
proc declare_labels {args} {
foreach arg $args {
set name [lindex $arg 0]
set text [lindex $arg 1]
if { $text == "" } {
set text $name
}
upvar $name label_var
set label_var [new_label $text]
proc ${name}: {args} [format {
define_label %s
uplevel $args
} $label_var]
}
}
# Assign elements from LINE to the elements of an array named
# "argvec" in the caller scope. The keys used are named in ARGS.
# If the wrong number of elements appear in LINE, error.
proc _get_args {line op args} {
if {[llength $line] != [llength $args] + 1} {
error "usage: $op [string toupper $args]"
}
upvar argvec argvec
foreach var $args value [lreplace $line 0 0] {
set argvec($var) $value
}
}
# This is a miniature assembler for location expressions. It is
# suitable for use in the attributes to a DIE. Its output is
# prefixed with "=" to make it automatically use DW_FORM_block.
#
# BODY is split by lines, and each line is taken to be a list.
#
# DWARF_VERSION is the DWARF version for the section where the location
# description is found.
#
# ADDR_SIZE is the length in bytes (4 or 8) of an address on the target
# machine (typically found in the header of the section where the location
# description is found).
#
# OFFSET_SIZE is the length in bytes (4 or 8) of an offset into a DWARF
# section. This typically depends on whether 32-bit or 64-bit DWARF is
# used, as indicated in the header of the section where the location
# description is found.
#
# (FIXME should use 'info complete' here.)
# Each list's first element is the opcode, either short or long
# forms are accepted.
# FIXME argument handling
# FIXME move docs
proc _location { body dwarf_version addr_size offset_size } {
variable _constants
foreach line [split $body \n] {
# Ignore blank lines, and allow embedded comments.
if {[lindex $line 0] == "" || [regexp -- {^[ \t]*#} $line]} {
continue
}
set opcode [_map_name [lindex $line 0] _OP]
_op .byte $_constants($opcode) $opcode
array unset argvec *
switch -exact -- $opcode {
DW_OP_addr {
_get_args $line $opcode size
_op .${addr_size}byte $argvec(size)
}
DW_OP_GNU_addr_index {
variable _debug_addr_index
variable _cu_addr_size
_op .uleb128 ${_debug_addr_index}
incr _debug_addr_index
_defer_output .debug_addr {
_op .${_cu_addr_size}byte [lindex $line 1]
}
}
DW_OP_regx {
_get_args $line $opcode register
_op .uleb128 $argvec(register)
}
DW_OP_pick -
DW_OP_const1u -
DW_OP_const1s {
_get_args $line $opcode const
_op .byte $argvec(const)
}
DW_OP_const2u -
DW_OP_const2s {
_get_args $line $opcode const
_op .2byte $argvec(const)
}
DW_OP_const4u -
DW_OP_const4s {
_get_args $line $opcode const
_op .4byte $argvec(const)
}
DW_OP_const8u -
DW_OP_const8s {
_get_args $line $opcode const
_op .8byte $argvec(const)
}
DW_OP_constu {
_get_args $line $opcode const
_op .uleb128 $argvec(const)
}
DW_OP_consts {
_get_args $line $opcode const
_op .sleb128 $argvec(const)
}
DW_OP_plus_uconst {
_get_args $line $opcode const
_op .uleb128 $argvec(const)
}
DW_OP_piece {
_get_args $line $opcode size
_op .uleb128 $argvec(size)
}
DW_OP_bit_piece {
_get_args $line $opcode size offset
_op .uleb128 $argvec(size)
_op .uleb128 $argvec(offset)
}
DW_OP_skip -
DW_OP_bra {
_get_args $line $opcode label
_op .2byte $argvec(label)
}
DW_OP_implicit_value {
set l1 [new_label "value_start"]
set l2 [new_label "value_end"]
_op .uleb128 "$l2 - $l1"
define_label $l1
foreach value [lrange $line 1 end] {
switch -regexp -- $value {
{^0x[[:xdigit:]]{1,2}$} {_op .byte $value}
{^0x[[:xdigit:]]{4}$} {_op .2byte $value}
{^0x[[:xdigit:]]{8}$} {_op .4byte $value}
{^0x[[:xdigit:]]{16}$} {_op .8byte $value}
default {
error "bad value '$value' in DW_OP_implicit_value"
}
}
}
define_label $l2
}
DW_OP_implicit_pointer -
DW_OP_GNU_implicit_pointer {
_get_args $line $opcode label offset
# Here label is a section offset.
if { $dwarf_version == 2 } {
_op .${addr_size}byte $argvec(label)
} else {
_op .${offset_size}byte $argvec(label)
}
_op .sleb128 $argvec(offset)
}
DW_OP_GNU_variable_value {
_get_args $line $opcode label
# Here label is a section offset.
if { $dwarf_version == 2 } {
_op .${addr_size}byte $argvec(label)
} else {
_op .${offset_size}byte $argvec(label)
}
}
DW_OP_deref_size {
_get_args $line $opcode size
_op .byte $argvec(size)
}
DW_OP_bregx {
_get_args $line $opcode register offset
_op .uleb128 $argvec(register)
_op .sleb128 $argvec(offset)
}
DW_OP_fbreg {
_get_args $line $opcode offset
_op .sleb128 $argvec(offset)
}
DW_OP_fbreg {
_op .sleb128 [lindex $line 1]
}
DW_OP_LLVM_offset_constu {
_op .uleb128 [lindex $line 1]
}
DW_OP_LLVM_extend {
_op .uleb128 [lindex $line 1]
_op .uleb128 [lindex $line 2]
}
DW_OP_LLVM_select_bit_piece {
_op .uleb128 [lindex $line 1]
_op .uleb128 [lindex $line 2]
}
default {
if {[llength $line] > 1} {
error "Unimplemented: operands in location for $opcode"
}
}
}
}
}
# Return a label that references the current position in the
# .debug_addr table. When a user is creating split DWARF they
# will define two CUs, the first will be the split DWARF content,
# and the second will be the non-split stub CU. The split DWARF
# CU fills in the .debug_addr section, but the non-split CU
# includes a reference to the start of the section. The label
# returned by this proc provides that reference.
proc debug_addr_label {} {
variable _debug_addr_index
set lbl [new_label "debug_addr_idx_${_debug_addr_index}_"]
_defer_output .debug_addr {
define_label $lbl
}
return $lbl
}
# Emit a DWARF CU.
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
# Current options are:
# is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
# default = 0 (32-bit)
# version n - DWARF version number to emit
# default = 4
# addr_size n - the size of addresses in bytes: 4, 8, or default
# default = default
# fission 0|1 - boolean indicating if generating Fission debug info
# default = 0
# label <label>
# - string indicating label to be defined at the start
# of the CU header.
# default = ""
# BODY is Tcl code that emits the DIEs which make up the body of
# the CU. It is evaluated in the caller's context.
proc cu {options body} {
variable _constants
variable _cu_count
variable _abbrev_section
variable _abbrev_num
variable _cu_label
variable _cu_version
variable _cu_addr_size
variable _cu_offset_size
variable _cu_is_fission
# Establish the defaults.
set is_64 0
set _cu_version 4
set _cu_addr_size default
set _cu_is_fission 0
set section ".debug_info"
set _abbrev_section ".debug_abbrev"
set label ""
foreach { name value } $options {
set value [uplevel 1 "subst \"$value\""]
switch -exact -- $name {
is_64 { set is_64 $value }
version { set _cu_version $value }
addr_size { set _cu_addr_size $value }
fission { set _cu_is_fission $value }
label { set label $value }
default { error "unknown option $name" }
}
}
if {$_cu_addr_size == "default"} {
if {[is_64_target]} {
set _cu_addr_size 8
} else {
set _cu_addr_size 4
}
}
set _cu_offset_size [expr { $is_64 ? 8 : 4 }]
if { $_cu_is_fission } {
set section ".debug_info.dwo"
set _abbrev_section ".debug_abbrev.dwo"
}
if {$_cu_version < 4} {
set _constants(SPECIAL_expr) $_constants(DW_FORM_block)
} else {
set _constants(SPECIAL_expr) $_constants(DW_FORM_exprloc)
}
_section $section
set cu_num [incr _cu_count]
set my_abbrevs [_compute_label "abbrev${cu_num}_begin"]
set _abbrev_num 1
set _cu_label [_compute_label "cu${cu_num}_begin"]
set start_label [_compute_label "cu${cu_num}_start"]
set end_label [_compute_label "cu${cu_num}_end"]
if { $label != "" } {
upvar $label my_label
set my_label $_cu_label
}
define_label $_cu_label
if {$is_64} {
_op .4byte 0xffffffff
_op .8byte "$end_label - $start_label"
} else {
_op .4byte "$end_label - $start_label"
}
define_label $start_label
_op .2byte $_cu_version Version
# The CU header for DWARF 4 and 5 are slightly different.
if { $_cu_version == 5 } {
_op .byte 0x1 "DW_UT_compile"
_op .byte $_cu_addr_size "Pointer size"
_op .${_cu_offset_size}byte $my_abbrevs Abbrevs
} else {
_op .${_cu_offset_size}byte $my_abbrevs Abbrevs
_op .byte $_cu_addr_size "Pointer size"
}
_defer_output $_abbrev_section {
define_label $my_abbrevs
}
uplevel $body
_defer_output $_abbrev_section {
# Emit the terminator.
_op .byte 0x0 "Abbrev end - Terminator"
}
define_label $end_label
}
# Emit a DWARF TU.
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
# Current options are:
# is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
# default = 0 (32-bit)
# version n - DWARF version number to emit
# default = 4
# addr_size n - the size of addresses in bytes: 4, 8, or default
# default = default
# fission 0|1 - boolean indicating if generating Fission debug info
# default = 0
# SIGNATURE is the 64-bit signature of the type.
# TYPE_LABEL is the label of the type defined by this TU,
# or "" if there is no type (i.e., type stubs in Fission).
# BODY is Tcl code that emits the DIEs which make up the body of
# the TU. It is evaluated in the caller's context.
proc tu {options signature type_label body} {
variable _cu_count
variable _abbrev_section
variable _abbrev_num
variable _cu_label
variable _cu_version
variable _cu_addr_size
variable _cu_offset_size
variable _cu_is_fission
# Establish the defaults.
set is_64 0
set _cu_version 4
set _cu_addr_size default
set _cu_is_fission 0
set section ".debug_types"
set _abbrev_section ".debug_abbrev"
foreach { name value } $options {
switch -exact -- $name {
is_64 { set is_64 $value }
version { set _cu_version $value }
addr_size { set _cu_addr_size $value }
fission { set _cu_is_fission $value }
default { error "unknown option $name" }
}
}
if {$_cu_addr_size == "default"} {
if {[is_64_target]} {
set _cu_addr_size 8
} else {
set _cu_addr_size 4
}
}
set _cu_offset_size [expr { $is_64 ? 8 : 4 }]
if { $_cu_is_fission } {
set section ".debug_types.dwo"
set _abbrev_section ".debug_abbrev.dwo"
}
_section $section
set cu_num [incr _cu_count]
set my_abbrevs [_compute_label "abbrev${cu_num}_begin"]
set _abbrev_num 1
set _cu_label [_compute_label "cu${cu_num}_begin"]
set start_label [_compute_label "cu${cu_num}_start"]
set end_label [_compute_label "cu${cu_num}_end"]
define_label $_cu_label
if {$is_64} {
_op .4byte 0xffffffff
_op .8byte "$end_label - $start_label"
} else {
_op .4byte "$end_label - $start_label"
}
define_label $start_label
_op .2byte $_cu_version Version
_op .${_cu_offset_size}byte $my_abbrevs Abbrevs
_op .byte $_cu_addr_size "Pointer size"
_op .8byte $signature Signature
if { $type_label != "" } {
uplevel declare_labels $type_label
upvar $type_label my_type_label
if {$is_64} {
_op .8byte "$my_type_label - $_cu_label"
} else {
_op .4byte "$my_type_label - $_cu_label"
}
} else {
if {$is_64} {
_op .8byte 0
} else {
_op .4byte 0
}
}
_defer_output $_abbrev_section {
define_label $my_abbrevs
}
uplevel $body
_defer_output $_abbrev_section {
# Emit the terminator.
_op .byte 0x0 "Abbrev end - Terminator"
}
define_label $end_label
}
# Emit a DWARF .debug_ranges unit.
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
# Current options are:
# is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
# default = 0 (32-bit)
#
# BODY is Tcl code that emits the content of the .debug_ranges
# unit, it is evaluated in the caller's context.
proc ranges {options body} {
variable _debug_ranges_64_bit
foreach { name value } $options {
switch -exact -- $name {
is_64 { set _debug_ranges_64_bit [subst $value] }
default { error "unknown option $name" }
}
}
set section ".debug_ranges"
_section $section
proc sequence { body } {
variable _debug_ranges_64_bit
# Emit the sequence of addresses.
proc base { addr } {
variable _debug_ranges_64_bit
if { $_debug_ranges_64_bit } then {
_op .8byte 0xffffffffffffffff "Base Marker"
_op .8byte $addr "Base Address"
} else {
_op .4byte 0xffffffff "Base Marker"
_op .4byte $addr "Base Address"
}
}
proc range { start end } {
variable _debug_ranges_64_bit
if { $_debug_ranges_64_bit } then {
_op .8byte $start "Start Address"
_op .8byte $end "End Address"
} else {
_op .4byte $start "Start Address"
_op .4byte $end "End Address"
}
}
uplevel $body
# End of the sequence.
if { $_debug_ranges_64_bit } then {
_op .8byte 0x0 "End of Sequence Marker (Part 1)"
_op .8byte 0x0 "End of Sequence Marker (Part 2)"
} else {
_op .4byte 0x0 "End of Sequence Marker (Part 1)"
_op .4byte 0x0 "End of Sequence Marker (Part 2)"
}
}
uplevel $body
}
# Emit a DWARF .debug_rnglists section.
#
# The target address size is based on the current target's address size.
#
# BODY must be Tcl code that emits the content of the section. It is
# evaluated in the caller's context.
#
# The `is-64 true|false` options tells whether to use 64-bit DWARF instead
# of 32-bit DWARF. The default is 32-bit.
proc rnglists { options body } {
variable _debug_rnglists_addr_size
variable _debug_rnglists_offset_size
variable _debug_rnglists_is_64_dwarf
parse_options {{"is-64" "false"}}
if [is_64_target] {
set _debug_rnglists_addr_size 8
} else {
set _debug_rnglists_addr_size 4
}
if { ${is-64} } {
set _debug_rnglists_offset_size 8
set _debug_rnglists_is_64_dwarf true
} else {
set _debug_rnglists_offset_size 4
set _debug_rnglists_is_64_dwarf false
}
_section ".debug_rnglists"
# Count of tables in the section.
variable _debug_rnglists_table_count 0
# Compute the label name for list at index LIST_IDX, for the current
# table.
proc _compute_list_label { list_idx } {
variable _debug_rnglists_table_count
return ".Lrnglists_table_${_debug_rnglists_table_count}_list_${list_idx}"
}
with_override Dwarf::table Dwarf::_rnglists_table {
uplevel $body
}
}
# Generate one rnglists table (header + offset array + range lists).
#
# This proc is meant to be used within proc rnglists' body. It is made
# available as `table` while inside proc rnglists' body.
#
# BODY must be Tcl code that emits the content of the table. It may call
# the LIST_ procedure to generate rnglists. It is evaluated in the
# caller's context.
#
# The `post-header-label` option can be used to define a label just after
# the header of the table. This is the label that a DW_AT_rnglists_base
# attribute will usually refer to.
#
# The `with-offset-array true|false` option can be used to control whether
# the headers of the location list tables have an array of offset. The
# default is true.
proc _rnglists_table { options body } {
variable _debug_rnglists_table_count
variable _debug_rnglists_addr_size
variable _debug_rnglists_offset_size
variable _debug_rnglists_is_64_dwarf
parse_options {
{post-header-label ""}
{with-offset-array true}
}
# Count of lists in the table.
variable _debug_rnglists_list_count 0
# Generate the lists ops first, because we need to know how many
# lists there are to generate the header and offset table.
set lists_ops [_defer_to_string {
with_override Dwarf::list_ Dwarf::_rnglists_list {
uplevel $body
}
}]
set post_unit_len_label \
[_compute_label "rnglists_table_${_debug_rnglists_table_count}_post_unit_len"]
set post_header_label \
[_compute_label "rnglists_table_${_debug_rnglists_table_count}_post_header"]
set table_end_label \
[_compute_label "rnglists_table_${_debug_rnglists_table_count}_end"]
# Emit the table header.
if { $_debug_rnglists_is_64_dwarf } {
_op .4byte 0xffffffff "unit length 1/2"
_op .8byte "$table_end_label - $post_unit_len_label" "unit length 2/2"
} else {
_op .4byte "$table_end_label - $post_unit_len_label" "unit length"
}
define_label $post_unit_len_label
_op .2byte 5 "dwarf version"
_op .byte $_debug_rnglists_addr_size "address size"
_op .byte 0 "segment selector size"
if { ${with-offset-array} } {
_op .4byte "$_debug_rnglists_list_count" "offset entry count"
} else {
_op .4byte 0 "offset entry count"
}
define_label $post_header_label
# Define the user post-header label, if provided.
if { ${post-header-label} != "" } {
define_label ${post-header-label}
}
# Emit the offset array.
if { ${with-offset-array} } {
for {set list_idx 0} {$list_idx < $_debug_rnglists_list_count} {incr list_idx} {
set list_label [_compute_list_label $list_idx]
_op .${_debug_rnglists_offset_size}byte "$list_label - $post_header_label" "offset of list $list_idx"
}
}
# Emit the actual list data.
_emit "$lists_ops"
define_label $table_end_label
incr _debug_rnglists_table_count
}
# Generate one rnglists range list.
#
# This proc is meant to be used within proc _rnglists_table's body. It is
# made available as `list_` while inside proc _rnglists_table's body.
#
# BODY may call the various procs defined below to generate list entries.
# They correspond to the range list entry kinds described in section 2.17.3
# of the DWARF 5 spec.
#
# To define a label pointing to the beginning of the list, use the
# conventional way of declaring and defining labels:
#
# declare_labels the_list
#
# the_list: list_ { ... }
proc _rnglists_list { body } {
variable _debug_rnglists_list_count
# Define a label for this list. It is used to build the offset
# array later.
set list_label [_compute_list_label $_debug_rnglists_list_count]
define_label $list_label
with_override Dwarf::start_end Dwarf::_rnglists_start_end {
uplevel $body
}
# Emit end of list.
_op .byte 0x00 "DW_RLE_end_of_list"
incr _debug_rnglists_list_count
}
# Emit a rnglists DW_RLE_start_end entry.
#
# This proc is meant to be used within proc _rnglists_list's body. It is
# made available as `start_end` while inside proc _rnglists_list's body.
proc _rnglists_start_end { start end } {
variable _debug_rnglists_addr_size
_op .byte 0x06 "DW_RLE_start_end"
_op .${_debug_rnglists_addr_size}byte $start "start"
_op .${_debug_rnglists_addr_size}byte $end "end"
}
# Emit a DWARF .debug_loclists section.
#
# The target address size is based on the current target's address size.
#
# BODY must be Tcl code that emits the content of the section. It is
# evaluated in the caller's context.
#
# The `is-64 true|false` options tells whether to use 64-bit DWARF instead
# of 32-bit DWARF. The default is 32-bit.
proc loclists { options body } {
variable _debug_loclists_addr_size
variable _debug_loclists_offset_size
variable _debug_loclists_is_64_dwarf
parse_options {{"is-64" "false"}}
if [is_64_target] {
set _debug_loclists_addr_size 8
} else {
set _debug_loclists_addr_size 4
}
if { ${is-64} } {
set _debug_loclists_offset_size 8
set _debug_loclists_is_64_dwarf true
} else {
set _debug_loclists_offset_size 4
set _debug_loclists_is_64_dwarf false
}
_section ".debug_loclists"
# Count of tables in the section.
variable _debug_loclists_table_count 0
# Compute the label name for list at index LIST_IDX, for the current
# table.
proc _compute_list_label { list_idx } {
variable _debug_loclists_table_count
return ".Lloclists_table_${_debug_loclists_table_count}_list_${list_idx}"
}
with_override Dwarf::table Dwarf::_loclists_table {
uplevel $body
}
}
# Generate one loclists table (header + offset array + location lists).
#
# This proc is meant to be used within proc loclists' body. It is made
# available as `table` while inside proc rnglists' body.
#
# BODY must be Tcl code that emits the content of the table. It may call
# the LIST_ procedure to generate rnglists. It is evaluated in the
# caller's context.
#
# The `post-header-label` option can be used to define a label just after
# the header of the table. This is the label that a DW_AT_loclists_base
# attribute will usually refer to.
#
# The `with-offset-array true|false` option can be used to control
# whether the headers of the location list tables have an array of
# offset. The default is true.
proc _loclists_table { options body } {
variable _debug_loclists_table_count
variable _debug_loclists_addr_size
variable _debug_loclists_offset_size
variable _debug_loclists_is_64_dwarf
parse_options {
{post-header-label ""}
{with-offset-array true}
}
# Count of lists in the table.
variable _debug_loclists_list_count 0
# Generate the lists ops first, because we need to know how many
# lists there are to generate the header and offset table.
set lists_ops [_defer_to_string {
with_override Dwarf::list_ Dwarf::_loclists_list {
uplevel $body
}
}]
set post_unit_len_label \
[_compute_label "loclists_table_${_debug_loclists_table_count}_post_unit_len"]
set post_header_label \
[_compute_label "loclists_table_${_debug_loclists_table_count}_post_header"]
set table_end_label \
[_compute_label "loclists_table_${_debug_loclists_table_count}_end"]
# Emit the table header.
if { $_debug_loclists_is_64_dwarf } {
_op .4byte 0xffffffff "unit length 1/2"
_op .8byte "$table_end_label - $post_unit_len_label" "unit length 2/2"
} else {
_op .4byte "$table_end_label - $post_unit_len_label" "unit length"
}
define_label $post_unit_len_label
_op .2byte 5 "DWARF version"
_op .byte $_debug_loclists_addr_size "address size"
_op .byte 0 "segment selector size"
if { ${with-offset-array} } {
_op .4byte "$_debug_loclists_list_count" "offset entry count"
} else {
_op .4byte 0 "offset entry count"
}
define_label $post_header_label
# Define the user post-header label, if provided.
if { ${post-header-label} != "" } {
define_label ${post-header-label}
}
# Emit the offset array.
if { ${with-offset-array} } {
for {set list_idx 0} {$list_idx < $_debug_loclists_list_count} {incr list_idx} {
set list_label [_compute_list_label $list_idx]
_op .${_debug_loclists_offset_size}byte "$list_label - $post_header_label" "offset of list $list_idx"
}
}
# Emit the actual list data.
_emit "$lists_ops"
define_label $table_end_label
incr _debug_loclists_table_count
}
# Generate one loclists location list.
#
# This proc is meant to be used within proc _loclists_table's body. It is
# made available as `list_` while inside proc _loclists_table's body.
#
# BODY may call the various procs defined below to generate list
# entries. They correspond to the location list entry kinds
# described in section 2.6.2 of the DWARF 5 spec.
#
# To define a label pointing to the beginning of the list, use
# the conventional way of declaring and defining labels:
#
# declare_labels the_list
#
# the_list: list_ {
# ...
# }
proc _loclists_list { body } {
variable _debug_loclists_list_count
# Count the location descriptions in this list.
variable _debug_loclists_locdesc_count 0
# Define a label for this list. It is used to build the offset
# array later.
set list_label [_compute_list_label $_debug_loclists_list_count]
define_label $list_label
with_override Dwarf::start_length Dwarf::_loclists_start_length {
with_override Dwarf::start_end Dwarf::_loclists_start_end {
uplevel $body
}}
# Emit end of list.
_op .byte 0x00 "DW_LLE_end_of_list"
incr _debug_loclists_list_count
}
# Emit a DW_LLE_start_length entry.
#
# This proc is meant to be used within proc _loclists_list's body. It is
# made available as `start_length` while inside proc _loclists_list's body.
proc _loclists_start_length { start length locdesc } {
variable _debug_loclists_is_64_dwarf
variable _debug_loclists_addr_size
variable _debug_loclists_offset_size
variable _debug_loclists_table_count
variable _debug_loclists_list_count
variable _debug_loclists_locdesc_count
set locdesc [uplevel [list subst $locdesc]]
_op .byte 0x08 "DW_LLE_start_length"
# Start and end of the address range.
_op .${_debug_loclists_addr_size}byte $start "start"
_op .uleb128 $length "length"
# Length of location description.
set locdesc_start_label ".Lloclists_table_${_debug_loclists_table_count}_list_${_debug_loclists_list_count}_locdesc_${_debug_loclists_locdesc_count}_start"
set locdesc_end_label ".Lloclists_table_${_debug_loclists_table_count}_list_${_debug_loclists_list_count}_locdesc_${_debug_loclists_locdesc_count}_end"
_op .uleb128 "$locdesc_end_label - $locdesc_start_label" "locdesc length"
define_label $locdesc_start_label
set dwarf_version 5
_location $locdesc $dwarf_version $_debug_loclists_addr_size $_debug_loclists_offset_size
define_label $locdesc_end_label
incr _debug_loclists_locdesc_count
}
# Emit a DW_LLE_start_end entry.
#
# This proc is meant to be used within proc _loclists_list's body. It is
# made available as `start_end` while inside proc _loclists_list's body.
proc _loclists_start_end { start end locdesc } {
variable _debug_loclists_is_64_dwarf
variable _debug_loclists_addr_size
variable _debug_loclists_offset_size
variable _debug_loclists_table_count
variable _debug_loclists_list_count
variable _debug_loclists_locdesc_count
set locdesc [uplevel [list subst $locdesc]]
_op .byte 0x07 "DW_LLE_start_end"
# Start and end of the address range.
_op .${_debug_loclists_addr_size}byte $start "start"
_op .${_debug_loclists_addr_size}byte $end "end"
# Length of location description.
set locdesc_start_label ".Lloclists_table_${_debug_loclists_table_count}_list_${_debug_loclists_list_count}_locdesc_${_debug_loclists_locdesc_count}_start"
set locdesc_end_label ".Lloclists_table_${_debug_loclists_table_count}_list_${_debug_loclists_list_count}_locdesc_${_debug_loclists_locdesc_count}_end"
_op .uleb128 "$locdesc_end_label - $locdesc_start_label" "locdesc length"
define_label $locdesc_start_label
set dwarf_version 5
_location $locdesc $dwarf_version $_debug_loclists_addr_size $_debug_loclists_offset_size
define_label $locdesc_end_label
incr _debug_loclists_locdesc_count
}
# Emit a DWARF .debug_line unit.
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
# Current options are:
# is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
# default = 0 (32-bit)
# version n - DWARF version number to emit
# default = 4
# addr_size n - the size of addresses in bytes: 4, 8, or default
# default = default
#
# LABEL is the label of the current unit (which is probably
# referenced by a DW_AT_stmt_list), or "" if there is no such
# label.
#
# BODY is Tcl code that emits the parts which make up the body of
# the line unit. It is evaluated in the caller's context. The
# following commands are available for the BODY section:
#
# include_dir "dirname" -- adds a new include directory
#
# file_name "file.c" idx -- adds a new file name. IDX is a
# 1-based index referencing an include directory or 0 for
# current directory.
proc lines {options label body} {
variable _line_count
variable _line_saw_file
variable _line_saw_program
variable _line_header_end_label
# Establish the defaults.
set is_64 0
set _unit_version 4
set _unit_addr_size default
set _line_saw_program 0
set _line_saw_file 0
set _default_is_stmt 1
foreach { name value } $options {
switch -exact -- $name {
is_64 { set is_64 $value }
version { set _unit_version $value }
addr_size { set _unit_addr_size $value }
default_is_stmt { set _default_is_stmt $value }
default { error "unknown option $name" }
}
}
if {$_unit_addr_size == "default"} {
if {[is_64_target]} {
set _unit_addr_size 8
} else {
set _unit_addr_size 4
}
}
set unit_num [incr _line_count]
set section ".debug_line"
_section $section
if { "$label" != "" } {
# Define the user-provided label at this point.
$label:
}
set unit_len_label [_compute_label "line${_line_count}_start"]
set unit_end_label [_compute_label "line${_line_count}_end"]
set header_len_label [_compute_label "line${_line_count}_header_start"]
set _line_header_end_label [_compute_label "line${_line_count}_header_end"]
if {$is_64} {
_op .4byte 0xffffffff
_op .8byte "$unit_end_label - $unit_len_label" "unit_length"
} else {
_op .4byte "$unit_end_label - $unit_len_label" "unit_length"
}
define_label $unit_len_label
_op .2byte $_unit_version version
if {$is_64} {
_op .8byte "$_line_header_end_label - $header_len_label" "header_length"
} else {
_op .4byte "$_line_header_end_label - $header_len_label" "header_length"
}
define_label $header_len_label
_op .byte 1 "minimum_instruction_length"
_op .byte $_default_is_stmt "default_is_stmt"
_op .byte 1 "line_base"
_op .byte 1 "line_range"
_op .byte 10 "opcode_base"
# The standard_opcode_lengths table. The number of arguments
# for each of the standard opcodes. Generating 9 entries here
# matches the use of 10 in the opcode_base above. These 9
# entries match the 9 standard opcodes for DWARF2, making use
# of only 9 should be fine, even if we are generating DWARF3
# or DWARF4.
_op .byte 0 "standard opcode 1"
_op .byte 1 "standard opcode 2"
_op .byte 1 "standard opcode 3"
_op .byte 1 "standard opcode 4"
_op .byte 1 "standard opcode 5"
_op .byte 0 "standard opcode 6"
_op .byte 0 "standard opcode 7"
_op .byte 0 "standard opcode 8"
_op .byte 1 "standard opcode 9"
proc include_dir {dirname} {
_op .ascii [_quote $dirname]
}
proc file_name {filename diridx} {
variable _line_saw_file
if "! $_line_saw_file" {
# Terminate the dir list.
_op .byte 0 "Terminator."
set _line_saw_file 1
}
_op .ascii [_quote $filename]
_op .sleb128 $diridx
_op .sleb128 0 "mtime"
_op .sleb128 0 "length"
}
proc program {statements} {
variable _line_saw_program
variable _line_header_end_label
variable _line
set _line 1
if "! $_line_saw_program" {
# Terminate the file list.
_op .byte 0 "Terminator."
define_label $_line_header_end_label
set _line_saw_program 1
}
proc DW_LNE_set_address {addr} {
_op .byte 0
set start [new_label "set_address_start"]
set end [new_label "set_address_end"]
_op .uleb128 "${end} - ${start}"
define_label ${start}
_op .byte 2
if {[is_64_target]} {
_op .8byte ${addr}
} else {
_op .4byte ${addr}
}
define_label ${end}
}
proc DW_LNE_end_sequence {} {
variable _line
_op .byte 0
_op .uleb128 1
_op .byte 1
set _line 1
}
proc DW_LNE_user { len opcode } {
set DW_LNE_lo_usr 0x80
set DW_LNE_hi_usr 0xff
if { $DW_LNE_lo_usr <= $opcode
&& $opcode <= $DW_LNE_hi_usr } {
_op .byte 0
_op .uleb128 $len
_op .byte $opcode
for {set i 1} {$i < $len} {incr i} {
_op .byte 0
}
} else {
error "unknown vendor specific extended opcode: $opcode"
}
}
proc DW_LNS_copy {} {
_op .byte 1
}
proc DW_LNS_negate_stmt {} {
_op .byte 6
}
proc DW_LNS_advance_pc {offset} {
_op .byte 2
_op .uleb128 ${offset}
}
proc DW_LNS_advance_line {offset} {
variable _line
_op .byte 3
_op .sleb128 ${offset}
set _line [expr $_line + $offset]
}
# A pseudo line number program instruction, that can be used instead
# of DW_LNS_advance_line. Rather than writing:
# {DW_LNS_advance_line [expr $line1 - 1]}
# {DW_LNS_advance_line [expr $line2 - $line1]}
# {DW_LNS_advance_line [expr $line3 - $line2]}
# we can just write:
# {line $line1}
# {line $line2}
# {line $line3}
proc line {line} {
variable _line
set offset [expr $line - $_line]
DW_LNS_advance_line $offset
}
proc DW_LNS_set_file {num} {
_op .byte 4
_op .sleb128 ${num}
}
foreach statement $statements {
uplevel 1 $statement
}
}
uplevel $body
rename include_dir ""
rename file_name ""
# Terminate dir list if we saw no files.
if "! $_line_saw_file" {
_op .byte 0 "Terminator."
}
# Terminate the file list.
if "! $_line_saw_program" {
_op .byte 0 "Terminator."
define_label $_line_header_end_label
}
define_label $unit_end_label
}
# Emit a DWARF .debug_aranges entry.
proc arange { options arange_start arange_length } {
parse_options {
{ comment "" }
{ seg_sel "" }
}
if { $comment != "" } {
# Wrap
set comment " ($comment)"
}
if { $seg_sel != "" } {
variable _seg_size
if { $_seg_size == 8 } {
set seg_op .8byte
} elseif { $_seg_size == 4 } {
set seg_op .4byte
} else {
error \
"Don't know how to handle segment selector size $_seg_size"
}
_op $seg_op $seg_sel "Address range segment selector$comment"
}
variable _addr_size
if { $_addr_size == 8 } {
set addr_op .8byte
} elseif { $_addr_size == 4 } {
set addr_op .4byte
}
_op $addr_op $arange_start "Address range start$comment"
_op $addr_op $arange_length "Address range length$comment"
}
# Emit a DWARF .debug_aranges unit.
#
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
# Current options are:
# is_64 0|1 - boolean indicating if you want to emit 64-bit DWARF
# default = 0 (32-bit)
# cu_is_64 0|1 - boolean indicating if LABEL refers to a 64-bit DWARF CU
# default = 0 (32-bit)
# section_version n
# - section version number to emit
# default = 2
# seg_size n - the size of the adress selector in bytes: 0, 4, or 8
# default = 0
#
# LABEL is the label of the corresponding CU.
#
# BODY is Tcl code that emits the parts which make up the body of
# the aranges unit. It is evaluated in the caller's context. The
# following commands are available for the BODY section:
#
# arange [-c <comment>] [<segment selector>] <start> <length>
# -- adds an address range.
proc aranges { options label body } {
variable _addr_size
variable _seg_size
# Handle options.
parse_options {
{ is_64 0 }
{ cu_is_64 0 }
{ section_version 2 }
{ seg_size 0 }
}
set _seg_size $seg_size
if { [is_64_target] } {
set _addr_size 8
} else {
set _addr_size 4
}
# Switch to .debug_aranges section.
_section .debug_aranges
# Keep track of offset from start of section entry to determine
# padding amount.
set offset 0
# Initial length.
declare_labels aranges_start aranges_end
set length "$aranges_end - $aranges_start"
set comment "Length"
if { $is_64 } {
_op .4byte 0xffffffff
_op .8byte $length $comment
incr offset 12
} else {
_op .4byte $length $comment
incr offset 4
}
# Start label.
aranges_start:
# Section version.
_op .2byte $section_version "Section version"
incr offset 2
# Offset into .debug_info.
upvar $label my_label
if { $cu_is_64 } {
_op .8byte $my_label "Offset into .debug_info"
incr offset 8
} else {
_op .4byte $my_label "Offset into .debug_info"
incr offset 4
}
# Address size.
_op .byte $_addr_size "Address size"
incr offset
# Segment selector size.
_op .byte $_seg_size "Segment selector size"
incr offset
# Padding.
set tuple_size [expr 2 * $_addr_size + $_seg_size]
while { 1 } {
if { [expr $offset % $tuple_size] == 0 } {
break
}
_op .byte 0 "Pad to $tuple_size byte boundary"
incr offset
}
# Range tuples.
uplevel $body
# Terminator tuple.
set comment "Terminator"
if { $_seg_size == 0 } {
arange {comment $comment} 0 0
} else {
arange {comment $comment seg_sel 0} 0 0
}
# End label.
aranges_end:
}
# Emit a .debug_loc entry.
proc _loc_entry { start end location_description } {
# Determine how to emit addresses.
variable _addr_size
if { $_addr_size == 8 } {
set addr_op .8byte
} elseif { $_addr_size == 4 } {
set addr_op .4byte
}
# Emit start and end address.
_op $addr_op $start "Start address"
_op $addr_op $end "End address"
declare_labels location_description_start
declare_labels location_description_end
# Emit length of location description.
set len "$location_description_end - $location_description_start"
_op .2byte $len "Location description length"
# Tag start of location description.
define_label $location_description_start
# Emit location description.
variable _cu_version
variable _cu_offset_size
_location $location_description $_cu_version $_addr_size \
$_cu_offset_size
# Tag end of location description.
define_label $location_description_end
}
# Emit a DWARF .debug_loc contribution.
#
# OPTIONS is a list with an even number of elements containing
# option-name and option-value pairs.
# Current options are:
# cu_is_64 0|1 - boolean indicating if references from location
# descriptions refer to a 64-bit DWARF CU.
# default = 0 (32-bit)
# cu_version n - section version of DWARF CU referenced from location
# descriptions.
# default = 4
#
# BODY is Tcl code that emits the parts which make up the body of
# the debug_loc contribution. It is evaluated in the caller's context.
# The following command is available for the BODY section:
#
# entry <start> <end> <location description>
# -- emit a .debug_loc entry
proc loc { options body } {
# Handle options.
parse_options {
{ cu_version 4 }
{ cu_is_64 0 }
}
# Export for use in BODY.
variable _addr_size
if { [is_64_target] } {
set _addr_size 8
} else {
set _addr_size 4
}
variable _cu_version
set _cu_version $cu_version
variable _cu_offset_size
if { $cu_is_64 == 1 } {
set _cu_offset_size 8
} else {
set _cu_offset_size 4
}
# Switch to .debug_loc section.
_section .debug_loc
# Introduce command 'entry'.
with_override Dwarf::entry Dwarf::_loc_entry {
# Emit entries.
uplevel $body
}
# Determine how to emit addresses.
if { $_addr_size == 8 } {
set addr_op .8byte
} elseif { $_addr_size == 4 } {
set addr_op .4byte
}
# Emit <End of list>.
set comment "<End of list>"
_op $addr_op 0 "$comment (Part 1/2)"
_op $addr_op 0 "$comment (Part 2/2)"
}
proc _empty_array {name} {
upvar $name the_array
catch {unset the_array}
set the_array(_) {}
unset the_array(_)
}
# Emit a .gnu_debugaltlink section with the given file name and
# build-id. The buildid should be represented as a hexadecimal
# string, like "ffeeddcc".
proc gnu_debugaltlink {filename buildid} {
_defer_output .gnu_debugaltlink {
_op .ascii [_quote $filename]
foreach {a b} [split $buildid {}] {
_op .byte 0x$a$b
}
}
}
proc _note {type name hexdata} {
set namelen [expr [string length $name] + 1]
# Name size.
_op .4byte $namelen
# Data size.
_op .4byte [expr [string length $hexdata] / 2]
# Type.
_op .4byte $type
# The name.
_op .ascii [_quote $name]
# Alignment.
set align 2
set total [expr {($namelen + (1 << $align) - 1) & -(1 << $align)}]
for {set i $namelen} {$i < $total} {incr i} {
_op .byte 0
}
# The data.
foreach {a b} [split $hexdata {}] {
_op .byte 0x$a$b
}
}
# Emit a note section holding the given build-id.
proc build_id {buildid} {
_defer_output {.note.gnu.build-id a note} {
# From elf/common.h.
set NT_GNU_BUILD_ID 3
_note $NT_GNU_BUILD_ID GNU $buildid
}
}
# Emit a dummy CU.
proc dummy_cu {} {
# Generate a CU with default options and empty body.
cu {label dummy_cu} {
}
# Generate an .debug_aranges entry for the dummy CU.
aranges {} dummy_cu {
}
}
# The top-level interface to the DWARF assembler.
# FILENAME is the name of the file where the generated assembly
# code is written.
# BODY is Tcl code to emit the assembly. It is evaluated via
# "eval" -- not uplevel as you might expect, because it is
# important to run the body in the Dwarf namespace.
#
# A typical invocation is something like:
# Dwarf::assemble $file {
# cu 0 2 8 {
# compile_unit {
# ...
# }
# }
# cu 0 2 8 {
# ...
# }
# }
proc assemble {filename body} {
variable _initialized
variable _output_file
variable _deferred_output
variable _defer
variable _label_num
variable _strings
variable _cu_count
variable _line_count
variable _line_saw_file
variable _line_saw_program
variable _line_header_end_label
variable _debug_ranges_64_bit
variable _debug_addr_index
if {!$_initialized} {
_read_constants
set _initialized 1
}
set _output_file [open $filename w]
set _cu_count -1
_empty_array _deferred_output
set _defer ""
set _label_num 0
_empty_array _strings
set _line_count 0
set _line_saw_file 0
set _line_saw_program 0
set _debug_ranges_64_bit [is_64_target]
set _debug_addr_index 0
# Dummy CU at the start to ensure that the first CU in $body is not
# the first in .debug_info.
dummy_cu
# Not "uplevel" here, because we want to evaluate in this
# namespace. This is somewhat bad because it means we can't
# readily refer to outer variables.
eval $body
# Dummy CU at the end to ensure that the last CU in $body is not
# the last in .debug_info.
dummy_cu
_write_deferred_output
catch {close $_output_file}
set _output_file {}
}
}