From: Mark Wielaard Date: Fri, 18 May 2018 22:46:02 +0000 (+0200) Subject: libdw: Handle GNU DebugFission split ranges. X-Git-Tag: elfutils-0.171~27 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=144b73c49acf3ed894e4635aedb9b0d1208ade2e;p=thirdparty%2Felfutils.git libdw: Handle GNU DebugFission split ranges. GNU DebugFission split dwarf handles DW_FORM_sec_offset specially for attributes that point to ranges. The .debug_ranges section is not in the .dwo file, but in the main/skeleton object file. The sec_offset is not relocated (in the ELF file), but is an offset against the skeleton DIE DW_AT_GNU_ranges_base attribute. dwarf_formudata is changed so it still looks like a normal offset ptr into the .debug_ranges section. dwarf_ranges is adapted to look for the .debug_ranges in the main object file. dwarf_highpc and dwarf_lowpc now handle the highpc and lowpc attributes being inherited for the split unit DIE from the skeleton. A new testcase is added to iterate over all ranges in a split GNU DebugFission file. Signed-off-by: Mark Wielaard --- diff --git a/libdw/ChangeLog b/libdw/ChangeLog index ab9675e47..4db0f5c1a 100644 --- a/libdw/ChangeLog +++ b/libdw/ChangeLog @@ -1,3 +1,15 @@ +2018-05-18 Mark Wielaard + + * dwarf_formudata.c (__libdw_formptr): Handle the special case + of IDX_debug_ranges for DW_UT_split_compile with version < 5. + * dwarf_highpc.c (dwarf_highpc): Use dwarf_lowpc, check for + split compile cudie. + * dwarf_lowpc.c (dwarf_lowpc): Check for split compile cudie. + * dwarf_ranges.c (dwarf_ranges): Switch cu and sectiondata for + split compile units. + * libdwP.h (struct Dwarf_CU): Add ranges_base field. + (__libdw_cu_ranges_base): New static inline function. + 2018-05-18 Mark Wielaard * libdw_findcu.c (__libdw_intern_next_unit): Init files to NULL. diff --git a/libdw/dwarf_formudata.c b/libdw/dwarf_formudata.c index 19d34f8e7..316ad8655 100644 --- a/libdw/dwarf_formudata.c +++ b/libdw/dwarf_formudata.c @@ -43,6 +43,17 @@ __libdw_formptr (Dwarf_Attribute *attr, int sec_index, return NULL; const Elf_Data *d = attr->cu->dbg->sectiondata[sec_index]; + Dwarf_CU *skel = NULL; /* See below, needed for GNU DebugFission. */ + if (unlikely (d == NULL + && sec_index == IDX_debug_ranges + && attr->cu->version < 5 + && attr->cu->unit_type == DW_UT_split_compile)) + { + skel = __libdw_find_split_unit (attr->cu); + if (skel != NULL) + d = skel->dbg->sectiondata[IDX_debug_ranges]; + } + if (unlikely (d == NULL)) { __libdw_seterrno (err_nodata); @@ -52,10 +63,41 @@ __libdw_formptr (Dwarf_Attribute *attr, int sec_index, Dwarf_Word offset; if (attr->form == DW_FORM_sec_offset) { - if (__libdw_read_offset (attr->cu->dbg, attr->cu->dbg, - cu_sec_idx (attr->cu), attr->valp, - attr->cu->offset_size, &offset, sec_index, 0)) - return NULL; + /* GNU DebugFission is slightly odd. It uses DW_FORM_sec_offset + in split units, but they are really (unrelocated) offsets + from the skeleton DW_AT_GNU_ranges_base (which is only used + for the split unit, not the skeleton ranges itself, see also + DW_AT_rnglists_base, which is used in DWARF5 for both, but + points to the offsets index). So it isn't really a formptr, + but an offset + base calculation. */ + if (unlikely (skel != NULL)) + { + Elf_Data *data = attr->cu->dbg->sectiondata[cu_sec_idx (attr->cu)]; + const unsigned char *datap = attr->valp; + size_t size = attr->cu->offset_size; + if (unlikely (data == NULL + || datap < (const unsigned char *) data->d_buf + || data->d_size < size + || ((size_t) (datap + - (const unsigned char *) data->d_buf) + > data->d_size - size))) + goto invalid; + + if (size == 4) + offset = read_4ubyte_unaligned (attr->cu->dbg, datap); + else + offset = read_8ubyte_unaligned (attr->cu->dbg, datap); + + offset += __libdw_cu_ranges_base (skel); + } + else + { + if (__libdw_read_offset (attr->cu->dbg, attr->cu->dbg, + cu_sec_idx (attr->cu), attr->valp, + attr->cu->offset_size, &offset, + sec_index, 0)) + return NULL; + } } else if (attr->cu->version > 3) goto invalid; diff --git a/libdw/dwarf_highpc.c b/libdw/dwarf_highpc.c index 207025450..1baffa7ef 100644 --- a/libdw/dwarf_highpc.c +++ b/libdw/dwarf_highpc.c @@ -1,7 +1,6 @@ /* Return high PC attribute of DIE. - Copyright (C) 2003, 2005, 2012 Red Hat, Inc. + Copyright (C) 2003, 2005, 2012, 2018 Red Hat, Inc. This file is part of elfutils. - Written by Ulrich Drepper , 2003. This file is free software; you can redistribute it and/or modify it under the terms of either @@ -39,8 +38,14 @@ int dwarf_highpc (Dwarf_Die *die, Dwarf_Addr *return_addr) { Dwarf_Attribute attr_high_mem; - Dwarf_Attribute *attr_high = INTUSE(dwarf_attr) (die, DW_AT_high_pc, - &attr_high_mem); + Dwarf_Attribute *attr_high; + /* Split compile DIEs inherit high_pc from their skeleton DIE. */ + if (is_cudie (die) && die->cu->unit_type == DW_UT_split_compile) + attr_high = INTUSE(dwarf_attr_integrate) (die, DW_AT_high_pc, + &attr_high_mem); + else + attr_high = INTUSE(dwarf_attr) (die, DW_AT_high_pc, &attr_high_mem); + if (attr_high == NULL) return -1; @@ -48,10 +53,7 @@ dwarf_highpc (Dwarf_Die *die, Dwarf_Addr *return_addr) return INTUSE(dwarf_formaddr) (attr_high, return_addr); /* DWARF 4 allows high_pc to be a constant offset from low_pc. */ - Dwarf_Attribute attr_low_mem; - if (INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (die, DW_AT_low_pc, - &attr_low_mem), - return_addr) == 0) + if (INTUSE(dwarf_lowpc) (die, return_addr) == 0) { Dwarf_Word uval; if (INTUSE(dwarf_formudata) (attr_high, &uval) == 0) diff --git a/libdw/dwarf_lowpc.c b/libdw/dwarf_lowpc.c index b3be2b0eb..4d743a724 100644 --- a/libdw/dwarf_lowpc.c +++ b/libdw/dwarf_lowpc.c @@ -1,7 +1,6 @@ /* Return low PC attribute of DIE. - Copyright (C) 2003, 2005 Red Hat, Inc. + Copyright (C) 2003, 2005, 2018 Red Hat, Inc. This file is part of elfutils. - Written by Ulrich Drepper , 2003. This file is free software; you can redistribute it and/or modify it under the terms of either @@ -38,10 +37,12 @@ int dwarf_lowpc (Dwarf_Die *die, Dwarf_Addr *return_addr) { - Dwarf_Attribute attr_mem; - - return INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (die, DW_AT_low_pc, - &attr_mem), - return_addr); + Dwarf_Attribute attr_mem, *attr; + /* Split compile DIEs inherit low_pc from their skeleton DIE. */ + if (is_cudie (die) && die->cu->unit_type == DW_UT_split_compile) + attr = INTUSE(dwarf_attr_integrate) (die, DW_AT_low_pc, &attr_mem); + else + attr = INTUSE(dwarf_attr) (die, DW_AT_low_pc, &attr_mem); + return INTUSE(dwarf_formaddr) (attr, return_addr); } INTDEF(dwarf_lowpc) diff --git a/libdw/dwarf_ranges.c b/libdw/dwarf_ranges.c index dbcfa2d48..b0450cf30 100644 --- a/libdw/dwarf_ranges.c +++ b/libdw/dwarf_ranges.c @@ -122,7 +122,17 @@ dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, /* We have to look for a noncontiguous range. */ size_t secidx = IDX_debug_ranges; - const Elf_Data *d = die->cu->dbg->sectiondata[secidx]; + Dwarf_CU *cu = die->cu; + const Elf_Data *d = cu->dbg->sectiondata[secidx]; + if (d == NULL && cu->unit_type == DW_UT_split_compile) + { + Dwarf_CU *skel = __libdw_find_split_unit (cu); + if (skel != NULL) + { + cu = skel; + d = cu->dbg->sectiondata[secidx]; + } + } const unsigned char *readp; const unsigned char *readendp; @@ -131,6 +141,10 @@ dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, Dwarf_Attribute attr_mem; Dwarf_Attribute *attr = INTUSE(dwarf_attr) (die, DW_AT_ranges, &attr_mem); + if (attr == NULL + && is_cudie (die) + && die->cu->unit_type == DW_UT_split_compile) + attr = INTUSE(dwarf_attr_integrate) (die, DW_AT_ranges, &attr_mem); if (attr == NULL) /* No PC attributes in this DIE at all, so an empty range list. */ return 0; @@ -144,7 +158,7 @@ dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, } else { - if (__libdw_offset_in_section (die->cu->dbg, + if (__libdw_offset_in_section (cu->dbg, secidx, offset, 1)) return -1; } @@ -156,9 +170,9 @@ dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, Dwarf_Addr end; next: - switch (__libdw_read_begin_end_pair_inc (die->cu->dbg, secidx, + switch (__libdw_read_begin_end_pair_inc (cu->dbg, secidx, &readp, readendp, - die->cu->address_size, + cu->address_size, &begin, &end, basep)) { case 0: diff --git a/libdw/libdwP.h b/libdw/libdwP.h index f73900575..2b5b5eadb 100644 --- a/libdw/libdwP.h +++ b/libdw/libdwP.h @@ -352,6 +352,11 @@ struct Dwarf_CU Don't access directly, call __libdw_cu_str_off_base. */ Dwarf_Off str_off_base; + /* The offset into the .debug_ranges section to use for GNU + DebugFission split units. Don't access directly, call + __libdw_cu_ranges_base. */ + Dwarf_Off ranges_base; + /* Memory boundaries of this CU. */ void *startp; void *endp; @@ -1055,6 +1060,27 @@ static inline Dwarf_Off __libdw_cu_str_off_base (Dwarf_CU *cu) } +static inline Dwarf_Off +__libdw_cu_ranges_base (Dwarf_CU *cu) +{ + if (cu->ranges_base == (Dwarf_Off) -1) + { + Dwarf_Off offset = 0; + Dwarf_Die cu_die = CUDIE(cu); + Dwarf_Attribute attr; + if (dwarf_attr (&cu_die, DW_AT_GNU_ranges_base, &attr) != NULL) + { + Dwarf_Word off; + if (dwarf_formudata (&attr, &off) == 0) + offset = off; + } + cu->ranges_base = offset; + } + + return cu->ranges_base; +} + + /* Helper function to set debugdir field in Dwarf, used from dwarf_begin_elf and libdwfl process_file. */ char * __libdw_debugdir (int fd); diff --git a/tests/ChangeLog b/tests/ChangeLog index 0370fbc66..a021a0191 100644 --- a/tests/ChangeLog +++ b/tests/ChangeLog @@ -1,3 +1,17 @@ +2018-05-18 Mark Wielaard + + * tests/Makefiles.am (check_PROGRAMS): Add all-dwarf-ranges. + (TESTS): Add run-all-dwarf-ranges.sh. + (EXTRA_DIST): Add run-all-dwarf-ranges.sh, + testfilesplitranges4.debug.bz2, testfile-ranges-hello.dwo.bz2 + and testfile-ranges-world.dwo.bz2. + (all_dwarf_ranges_LDADD): New variable. + * all-dwarf-ranges.c: New test program. + * run-all-dwarf-ranges: New test runner. + * testfile-ranges-hello.dwo.bz2: New test file. + * testfile-ranges-world.dwo.bz2: Likewise. + * testfilesplitranges4.debug.bz2: Likewise. + 2018-05-18 Mark Wielaard * run-get-files.sh: Add testcases for testfile-splitdwarf-4, diff --git a/tests/Makefile.am b/tests/Makefile.am index 05a5441b1..08d846495 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -56,7 +56,8 @@ check_PROGRAMS = arextract arsymtest newfile saridx scnnames sectiondump \ elfshphehdr elfstrmerge dwelfgnucompressed elfgetchdr \ elfgetzdata elfputzdata zstrptr emptyfile vendorelf \ fillfile dwarf_default_lower_bound dwarf-die-addr-die \ - get-units-invalid get-units-split attr-integrate-skel + get-units-invalid get-units-split attr-integrate-skel \ + all-dwarf-ranges asm_TESTS = asm-tst1 asm-tst2 asm-tst3 asm-tst4 asm-tst5 \ asm-tst6 asm-tst7 asm-tst8 asm-tst9 @@ -141,7 +142,8 @@ TESTS = run-arextract.sh run-arsymtest.sh run-ar.sh newfile test-nlist \ emptyfile vendorelf fillfile dwarf_default_lower_bound \ run-dwarf-die-addr-die.sh \ run-get-units-invalid.sh run-get-units-split.sh \ - run-attr-integrate-skel.sh + run-attr-integrate-skel.sh \ + run-all-dwarf-ranges.sh if !BIARCH export ELFUTILS_DISABLE_BIARCH = 1 @@ -366,7 +368,9 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \ testfile-hello4.dwo.bz2 testfile-hello5.dwo.bz2 \ testfile-splitdwarf-4.bz2 testfile-splitdwarf-5.bz2 \ testfile-world5.dwo.bz2 testfile-world4.dwo.bz2 \ - run-attr-integrate-skel.sh + run-attr-integrate-skel.sh \ + run-all-dwarf-ranges.sh testfilesplitranges4.debug.bz2 \ + testfile-ranges-hello.dwo.bz2 testfile-ranges-world.dwo.bz2 if USE_VALGRIND valgrind_cmd='valgrind -q --leak-check=full --error-exitcode=1' @@ -528,6 +532,7 @@ dwarf_die_addr_die_LDADD = $(libdw) get_units_invalid_LDADD = $(libdw) get_units_split_LDADD = $(libdw) attr_integrate_skel_LDADD = $(libdw) +all_dwarf_ranges_LDADD = $(libdw) # We want to test the libelf header against the system elf.h header. # Don't include any -I CPPFLAGS. diff --git a/tests/all-dwarf-ranges.c b/tests/all-dwarf-ranges.c new file mode 100644 index 000000000..4331a05b1 --- /dev/null +++ b/tests/all-dwarf-ranges.c @@ -0,0 +1,90 @@ +/* Test program for dwarf_ranges + Copyright (C) 2015, 2018 Red Hat, Inc. + This file is part of elfutils. + + This file 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. + + elfutils 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 . */ + +#include +#include ELFUTILS_HEADER(dw) +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static void +ranges_die (Dwarf_Die *die) +{ + Dwarf_Addr base, start, end; + int ranges = dwarf_ranges (die, 0, &base, &start, &end); + if (ranges < 0) + puts (dwarf_errmsg (-1)); + else if (ranges > 0) + { + printf ("die: %s (%x)\n", dwarf_diename (die) ?: "", + dwarf_tag (die)); + for (ptrdiff_t off = 0; + (off = dwarf_ranges (die, off, &base, &start, &end)); ) + if (off == -1) + { + puts (dwarf_errmsg (-1)); + break; + } + else + printf (" %"PRIx64"..%"PRIx64"\n", start, end); + printf ("\n"); + } +} + +static void +walk_tree (Dwarf_Die *dwarf_die) +{ + Dwarf_Die die = *dwarf_die; + do + { + Dwarf_Die child; + ranges_die (&die); + if (dwarf_child (&die, &child) == 0) + walk_tree (&child); + } + while (dwarf_siblingof (&die, &die) == 0); +} + +int +main (int argc, char *argv[]) +{ + assert (argc >= 2); + const char *name = argv[1]; + + int fd = open (name, O_RDONLY); + Dwarf *dbg = dwarf_begin (fd, DWARF_C_READ); + + Dwarf_CU *cu = NULL; + Dwarf_Die cudie, subdie; + uint8_t unit_type; + while (dwarf_get_units (dbg, cu, &cu, NULL, + &unit_type, &cudie, &subdie) == 0) + { + Dwarf_Die die = (unit_type == DW_UT_skeleton + ? subdie : cudie); + walk_tree (&die); + } + dwarf_end (dbg); + + return 0; +} diff --git a/tests/run-all-dwarf-ranges.sh b/tests/run-all-dwarf-ranges.sh new file mode 100755 index 000000000..0bd641b08 --- /dev/null +++ b/tests/run-all-dwarf-ranges.sh @@ -0,0 +1,49 @@ +#! /bin/sh +# Copyright (C) 2018 Red Hat, Inc. +# This file is part of elfutils. +# +# This file 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. +# +# elfutils 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 . + +. $srcdir/test-subr.sh + +# See run-dwarf-ranges.sh +# Compiled with: +# gcc -c -O2 -o testfile-ranges-hello.o -gsplit-dwarf -gdwarf-4 hello.c +# gcc -c -O2 -o testfile-ranges-world.o -gsplit-dwarf -gdwarf-4 world.c +# gcc -o testfilesplitranges4 -O2 \ +# testfile-ranges-hello.o testfile-ranges-world.o +# eu-strip -f testfilesplitranges4.debug testfilesplitranges4 + +testfiles testfilesplitranges4.debug +testfiles testfile-ranges-hello.dwo testfile-ranges-world.dwo + +testrun_compare ${abs_builddir}/all-dwarf-ranges testfilesplitranges4.debug <<\EOF +die: hello.c (11) + 4004e0..4004ff + 4003e0..4003f7 + +die: world.c (11) + 400500..400567 + +die: happy (1d) + 8009e0..8009ff + 8008e0..8008f7 + +die: sad (1d) + 400530..400534 + 400535..40053f + +EOF + +exit 0 diff --git a/tests/testfile-ranges-hello.dwo.bz2 b/tests/testfile-ranges-hello.dwo.bz2 new file mode 100644 index 000000000..fac246728 Binary files /dev/null and b/tests/testfile-ranges-hello.dwo.bz2 differ diff --git a/tests/testfile-ranges-world.dwo.bz2 b/tests/testfile-ranges-world.dwo.bz2 new file mode 100644 index 000000000..27ad06d56 Binary files /dev/null and b/tests/testfile-ranges-world.dwo.bz2 differ diff --git a/tests/testfilesplitranges4.debug.bz2 b/tests/testfilesplitranges4.debug.bz2 new file mode 100755 index 000000000..df8e3ac48 Binary files /dev/null and b/tests/testfilesplitranges4.debug.bz2 differ