From 0224619f6085908935f689b87e1ac4e460bb1e71 Mon Sep 17 00:00:00 2001 From: Jan Kratochvil Date: Mon, 20 Feb 2017 20:53:22 +0100 Subject: [PATCH] DWARF-5: DW_FORM_data16 DWARF-5 has new form DW_FORM_data16. The problem is that GDB cannot pass 16-byte constant as a constant value as that would require GDB to use GCC extension __int128. Formerly such data was coded as DW_FORM_block* so GDB still decodes DW_FORM_data16 like DW_FORM_block*. gdb/ChangeLog 2017-02-20 Jan Kratochvil * dwarf2read.c (skip_one_die, read_attribute_value) (dwarf2_const_value_attr, dump_die_shallow) (dwarf2_get_attr_constant_value, dwarf2_fetch_constant_bytes) (skip_form_bytes, attr_form_is_constant): Handle DW_FORM_data16. gdb/testsuite/ChangeLog 2017-02-20 Jan Kratochvil * gdb.dwarf2/formdata16.c: New file. * gdb.dwarf2/formdata16.exp: New file. * lib/dwarf.exp (Dwarf): Add DW_FORM_data16. --- gdb/ChangeLog | 7 +++ gdb/dwarf2read.c | 25 +++++++- gdb/testsuite/ChangeLog | 6 ++ gdb/testsuite/gdb.dwarf2/formdata16.c | 22 +++++++ gdb/testsuite/gdb.dwarf2/formdata16.exp | 77 +++++++++++++++++++++++++ gdb/testsuite/lib/dwarf.exp | 4 ++ 6 files changed, 140 insertions(+), 1 deletion(-) create mode 100644 gdb/testsuite/gdb.dwarf2/formdata16.c create mode 100644 gdb/testsuite/gdb.dwarf2/formdata16.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 83fcd10df6..2de892a05f 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2017-02-20 Jan Kratochvil + + * dwarf2read.c (skip_one_die, read_attribute_value) + (dwarf2_const_value_attr, dump_die_shallow) + (dwarf2_get_attr_constant_value, dwarf2_fetch_constant_bytes) + (skip_form_bytes, attr_form_is_constant): Handle DW_FORM_data16. + 2017-02-20 Jan Kratochvil * dwarf2read.c (read_file_scope): Rename DW_MACRO_GNU_*. diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index c7a2e73c11..ae7d3f2474 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -7414,6 +7414,9 @@ skip_one_die (const struct die_reader_specs *reader, const gdb_byte *info_ptr, case DW_FORM_ref_sig8: info_ptr += 8; break; + case DW_FORM_data16: + info_ptr += 16; + break; case DW_FORM_string: read_direct_string (abfd, info_ptr, &bytes_read); info_ptr += bytes_read; @@ -16554,6 +16557,13 @@ read_attribute_value (const struct die_reader_specs *reader, DW_UNSND (attr) = read_8_bytes (abfd, info_ptr); info_ptr += 8; break; + case DW_FORM_data16: + blk = dwarf_alloc_block (cu); + blk->size = 16; + blk->data = read_n_bytes (abfd, info_ptr, 16); + info_ptr += 16; + DW_BLOCK (attr) = blk; + break; case DW_FORM_sec_offset: DW_UNSND (attr) = read_offset (abfd, info_ptr, &cu->header, &bytes_read); info_ptr += bytes_read; @@ -19297,6 +19307,7 @@ dwarf2_const_value_attr (const struct attribute *attr, struct type *type, case DW_FORM_block4: case DW_FORM_block: case DW_FORM_exprloc: + case DW_FORM_data16: blk = DW_BLOCK (attr); if (TYPE_LENGTH (type) != blk->size) dwarf2_const_value_length_mismatch_complaint (name, blk->size, @@ -20251,6 +20262,9 @@ dump_die_shallow (struct ui_file *f, int indent, struct die_info *die) fprintf_unfiltered (f, "expression: size %s", pulongest (DW_BLOCK (&die->attrs[i])->size)); break; + case DW_FORM_data16: + fprintf_unfiltered (f, "constant of 16 bytes"); + break; case DW_FORM_ref_addr: fprintf_unfiltered (f, "ref address: "); fputs_filtered (hex_string (DW_UNSND (&die->attrs[i])), f); @@ -20412,6 +20426,7 @@ dwarf2_get_attr_constant_value (const struct attribute *attr, int default_value) return DW_UNSND (attr); else { + /* For DW_FORM_data16 see attr_form_is_constant. */ complaint (&symfile_complaints, _("Attribute value is not a constant (%s)"), dwarf_form_name (attr->form)); @@ -20695,6 +20710,7 @@ dwarf2_fetch_constant_bytes (sect_offset offset, case DW_FORM_block4: case DW_FORM_block: case DW_FORM_exprloc: + case DW_FORM_data16: result = DW_BLOCK (attr)->data; *len = DW_BLOCK (attr)->size; break; @@ -21603,6 +21619,10 @@ skip_form_bytes (bfd *abfd, const gdb_byte *bytes, const gdb_byte *buffer_end, bytes += 8; break; + case DW_FORM_data16: + bytes += 16; + break; + case DW_FORM_string: read_direct_string (abfd, bytes, &bytes_read); bytes += bytes_read; @@ -22266,7 +22286,10 @@ attr_form_is_section_offset (const struct attribute *attr) (lineptr, loclistptr, macptr or rangelistptr). The DWARF spec says that, if an attribute's can be either a constant or one of the section offset classes, DW_FORM_data4 and DW_FORM_data8 should be - taken as section offsets, not constants. */ + taken as section offsets, not constants. + + DW_FORM_data16 is not considered as dwarf2_get_attr_constant_value + cannot handle that. */ static int attr_form_is_constant (const struct attribute *attr) diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index e235c5f4f4..c18f1e6bbd 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2017-02-20 Jan Kratochvil + + * gdb.dwarf2/formdata16.c: New file. + * gdb.dwarf2/formdata16.exp: New file. + * lib/dwarf.exp (Dwarf): Add DW_FORM_data16. + 2017-02-20 Jan Kratochvil * gdb.arch/amd64-entry-value-param-dwarf5.S: New file. diff --git a/gdb/testsuite/gdb.dwarf2/formdata16.c b/gdb/testsuite/gdb.dwarf2/formdata16.c new file mode 100644 index 0000000000..956545fdbe --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/formdata16.c @@ -0,0 +1,22 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2017 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 . */ + +int +main () +{ + return 0; +} diff --git a/gdb/testsuite/gdb.dwarf2/formdata16.exp b/gdb/testsuite/gdb.dwarf2/formdata16.exp new file mode 100644 index 0000000000..bba2015e47 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/formdata16.exp @@ -0,0 +1,77 @@ +# Copyright 2017 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 . + +load_lib dwarf.exp + +# This test can only be run on targets which support DWARF-2 and use gas. +if {![dwarf2_support]} { + return 0 +} + +standard_testfile .c formdata16-dw.S + +# We need to know the endianess in order +# to write some of the debugging info we'd like to generate. +if [prepare_for_testing "failed to prepare for endianness test" ${testfile} ${srcfile}] { + return -1 +} + +set endianness "little" +set test "show endian" +gdb_test_multiple $test $test { + -re "(.* )(big|little)( endian.*)\r\n$gdb_prompt $" { + set endianness $expect_out(2,string) + pass "endianness" + } +} + +set high "0x123456789abcdef0" +set low "0x0fedcba987654321" +if { $endianness == "big" } { + set pair $high,$low +} else { + set pair $low,$high +} + +# Make some DWARF for the test. +set asm_file [standard_output_file $srcfile2] +Dwarf::assemble $asm_file { + global pair + + cu { addr_size 4 } { + compile_unit {} { + declare_labels int_label + + int_label: DW_TAG_base_type { + {DW_AT_byte_size 16 DW_FORM_udata} + {DW_AT_encoding @DW_ATE_unsigned} + {DW_AT_name "__uint128"} + } + + DW_TAG_variable { + {name xxx} + {type :$int_label} + {const_value $pair DW_FORM_data16} + } + } + } +} + +if { [prepare_for_testing "failed to prepare" ${testfile} \ + [list $srcfile $asm_file] {nodebug}] } { + return -1 +} + +gdb_test "p/x xxx" " = 0x123456789abcdef00fedcba987654321" diff --git a/gdb/testsuite/lib/dwarf.exp b/gdb/testsuite/lib/dwarf.exp index 149038c91e..1ccdc5dc1b 100644 --- a/gdb/testsuite/lib/dwarf.exp +++ b/gdb/testsuite/lib/dwarf.exp @@ -481,6 +481,10 @@ namespace eval Dwarf { _op .8byte $value } + DW_FORM_data16 { + _op .8byte $value + } + DW_FORM_strp { variable _strings variable _cu_offset_size