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Re: [RFA/DWARF] constant class of DW_AT_high_pc is offset for version >=4 only.
- From: Joel Brobecker <brobecker at adacore dot com>
- To: gdb-patches at sourceware dot org
- Date: Tue, 18 Feb 2014 14:30:00 +0100
- Subject: Re: [RFA/DWARF] constant class of DW_AT_high_pc is offset for version >=4 only.
- Authentication-results: sourceware.org; auth=none
- References: <1392478818-30320-1-git-send-email-brobecker at adacore dot com>
Hello,
Testing reveals that the test failed on some platforms:
(gdb) b world
Breakpoint 1 at 0x4005c4
Upon investigating it, it turns out that we were accessing the value
of the attribute using:
high = DW_ADDR (attr_high);
This is not correct, since DW_ADDR assumes the attribute's form
is an address, whereas the test was using a data form, which means
we should have been using DW_UNSND. On some platforms, DW_ADDR
happens to work, but that's only pure luck related to the two
components being stored within the same union. But on ppc-linux,
the attribute value was stored in the DW_UNSND component, and
reading it back using DW_ADDR returned zero/garbage.
In addition to revealing a bug in my patch, this revealed a slightly
more general issue, which is the assumption that address attributes
are always encoded using address forms. So, I amended my patch to
read addresses in a way that takes the attribute's form into account.
Apart from increasing the number of edits, all mostly mechanical,
I find that it simplified the handling for DW_AT_high_pc quite
a bit, thanks to the introduction of a function getting the attribute
value.
Changes compared to the previous version:
1. The introduction of attr_value_as_address, to be used
in place of DW_ADDR when dealing with address attributes.
I left a few uses of this macro in the situations where
we actually know that the form is an address form.
2. Instead of duplicating everywhere the conditions for
non-address forms in the handling of DW_AT_high_pc
attributes, I used the attr_form_is_constant function
instead. It's not stricly the same, but I think it is
closer to the DWARF reference.
3. Some very minor modifications of the assembly files in our
testcase to make it compilable on a larger number of targets:
Removing some of the extra parameters for the .section
pseudo-op, as well as using .2byte instead of .value.
4. In our testcase, I also adjusted the DW_AT_low_pc attributes
to be encoded using DW_FORM_data4, to be consistent with
the DW_AT_high_pc attributes, as well as to test reading
of that attribute in constant form.
gdb/ChangeLog:
* dwarf2read.c (attr_value_as_address): New function.
(dwarf2_find_base_address, read_call_site_scope): Use
attr_value_as_address in place of DW_ADDR.
(dwarf2_get_pc_bounds): Use attr_value_as_address to get
the low and high addresses. Slight rework of the handling
of the high pc being a constant form, and limit it to
DWARF verson 4 or higher.
(dwarf2_record_block_ranges): Likewise.
(read_partial_die): Likewise.
(new_symbol_full): Use attr_value_as_address in place of DW_ADDR.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S: New file.
* gdb.dwarf2/dw2-abs-hi-pc-hello.c: New file.
* gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S: New file.
* gdb.dwarf2/dw2-abs-hi-pc-world.c: New file.
* gdb.dwarf2/dw2-abs-hi-pc.c: New file.
* gdb.dwarf2/dw2-abs-hi-pc.exp: New file.
Tested on x86_64-linux. The testcase was also testing on ppc-linux,
where it was failing prior to the second iteration of this patch.
OK to commit?
Thanks,
--
Joel
>From 228e0cc1973bae4d1cc3c80582f4bf8acc71b482 Mon Sep 17 00:00:00 2001
From: Joel Brobecker <brobecker@adacore.com>
Date: Sat, 15 Feb 2014 19:09:58 +0400
Subject: [PATCH] DWARF: Read constant-class addresses correctly
Starting with DWARF version 4, the description of the DW_AT_high_pc
attribute was amended to say:
if it is of class constant, the value is an unsigned integer offset
which when added to the low PC gives the address of the first
location past the last instruction associated with the entity.
A change was made in Apr 27th, 2012 to reflect that change:
| commit 91da14142c0171e58a91ad58a32fd010b700e761
| Author: Mark Wielaard <mjw@redhat.com>
| Date: Fri Apr 27 18:55:19 2012 +0000
|
| * dwarf2read.c (dwarf2_get_pc_bounds): Check DW_AT_high_pc form to
| see whether it is an address or a constant offset from DW_AT_low_pc.
| (dwarf2_record_block_ranges): Likewise.
| (read_partial_die): Likewise.
Unfortunately, this new interpretation is now used regardless of
the CU's DWARF version. It turns out that one of WindRiver's compilers
(FTR: Diabdata 4.4) is generating DWARF version 2 info with
DW_AT_high_pc attributes using the data4 form. Because of that,
we miscompute all high PCs incorrectly. This leads to a lot of
symtabs having overlapping ranges, which in turn causes havoc
in pc-to-symtab-and-line translations.
One visible effect is when inserting a breakpoint on a given function:
(gdb) b world
Breakpoint 1 at 0x4005c4
The source location of the breakpoint is missing. The output should be:
(gdb) b world
Breakpoint 1 at 0x4005c8: file dw2-rel-hi-pc-world.c, line 24.
What happens in this case is that the pc-to-SAL translation first
starts be trying to find the symtab associated to our PC using
each symtab's ranges. Because of the high_pc miscomputation,
many symtabs end up matching, and the heuristic trying to select
the most probable one unfortunately returns one that is unrelated
(it really had no change in this case to do any better). Once we
have the wrong symtab, the start searching the associated linetable,
where the addresses are correct, thus finding no match, and therefore
no SAL.
More generally, this issue revealed that GDB makes the implicit
assumption that all address attributes are always encoded using
an address form (because we use the DW_ADDR macro to access the
attribute value, regardless of its form).
This patch introduces a new function "attr_value_as_address" which
uses the correct accessor for getting the value of a given attribute.
It then adjust the code throughout this unit to use this function
instead of assuming that addresses always have the DW_FORM_addr
format. In particular, this allows us to handle attributes such
as DW_AT_low_pc and DW_AT_entry_pc correctly when using constant
forms.
It also fixes the original issue of miscomputing the high_pc
by limiting the new interpretation of constant form DW_AT_high_pc
attributes to units using DWARF version 4 or later.
gdb/ChangeLog:
* dwarf2read.c (attr_value_as_address): New function.
(dwarf2_find_base_address, read_call_site_scope): Use
attr_value_as_address in place of DW_ADDR.
(dwarf2_get_pc_bounds): Use attr_value_as_address to get
the low and high addresses. Slight rework of the handling
of the high pc being a constant form, and limit it to
DWARF verson 4 or higher.
(dwarf2_record_block_ranges): Likewise.
(read_partial_die): Likewise.
(new_symbol_full): Use attr_value_as_address in place of DW_ADDR.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S: New file.
* gdb.dwarf2/dw2-abs-hi-pc-hello.c: New file.
* gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S: New file.
* gdb.dwarf2/dw2-abs-hi-pc-world.c: New file.
* gdb.dwarf2/dw2-abs-hi-pc.c: New file.
* gdb.dwarf2/dw2-abs-hi-pc.exp: New file.
Tested on x86_64-linux.
---
gdb/dwarf2read.c | 62 +++++----
gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S | 151 +++++++++++++++++++++
gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c | 28 ++++
gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S | 151 +++++++++++++++++++++
gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c | 28 ++++
gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.c | 28 ++++
gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp | 36 +++++
7 files changed, 456 insertions(+), 28 deletions(-)
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.c
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 54c538a..999765b 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -1939,6 +1939,22 @@ byte_swap (offset_type value)
#define MAYBE_SWAP(V) (V)
#endif /* WORDS_BIGENDIAN */
+/* Read the given attribute value as an address, taking the attribute's
+ form into account. */
+
+static CORE_ADDR
+attr_value_as_address (struct attribute *attr)
+{
+ CORE_ADDR addr;
+
+ if (attr->form != DW_FORM_addr && attr->form != DW_FORM_GNU_addr_index)
+ addr = DW_UNSND (attr);
+ else
+ addr = DW_ADDR (attr);
+
+ return addr;
+}
+
/* The suffix for an index file. */
#define INDEX_SUFFIX ".gdb-index"
@@ -4201,7 +4217,7 @@ dwarf2_find_base_address (struct die_info *die, struct dwarf2_cu *cu)
attr = dwarf2_attr (die, DW_AT_entry_pc, cu);
if (attr)
{
- cu->base_address = DW_ADDR (attr);
+ cu->base_address = attr_value_as_address (attr);
cu->base_known = 1;
}
else
@@ -4209,7 +4225,7 @@ dwarf2_find_base_address (struct die_info *die, struct dwarf2_cu *cu)
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr)
{
- cu->base_address = DW_ADDR (attr);
+ cu->base_address = attr_value_as_address (attr);
cu->base_known = 1;
}
}
@@ -11233,7 +11249,7 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
die->offset.sect_off, objfile_name (objfile));
return;
}
- pc = DW_ADDR (attr) + baseaddr;
+ pc = attr_value_as_address (attr) + baseaddr;
if (cu->call_site_htab == NULL)
cu->call_site_htab = htab_create_alloc_ex (16, core_addr_hash, core_addr_eq,
@@ -11674,12 +11690,10 @@ dwarf2_get_pc_bounds (struct die_info *die, CORE_ADDR *lowpc,
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr)
{
- low = DW_ADDR (attr);
- if (attr_high->form == DW_FORM_addr
- || attr_high->form == DW_FORM_GNU_addr_index)
- high = DW_ADDR (attr_high);
- else
- high = low + DW_UNSND (attr_high);
+ low = attr_value_as_address (attr);
+ high = attr_value_as_address (attr_high);
+ if (cu->header.version >= 4 && attr_form_is_constant (attr_high))
+ high += low;
}
else
/* Found high w/o low attribute. */
@@ -11845,13 +11859,11 @@ dwarf2_record_block_ranges (struct die_info *die, struct block *block,
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr)
{
- CORE_ADDR low = DW_ADDR (attr);
- CORE_ADDR high;
- if (attr_high->form == DW_FORM_addr
- || attr_high->form == DW_FORM_GNU_addr_index)
- high = DW_ADDR (attr_high);
- else
- high = low + DW_UNSND (attr_high);
+ CORE_ADDR low = attr_value_as_address (attr);
+ CORE_ADDR high = attr_value_as_address (attr_high);
+
+ if (cu->header.version >= 4 && attr_form_is_constant (attr_high))
+ high += low;
record_block_range (block, baseaddr + low, baseaddr + high - 1);
}
@@ -15240,18 +15252,13 @@ read_partial_die (const struct die_reader_specs *reader,
break;
case DW_AT_low_pc:
has_low_pc_attr = 1;
- part_die->lowpc = DW_ADDR (&attr);
+ part_die->lowpc = attr_value_as_address (&attr);
break;
case DW_AT_high_pc:
has_high_pc_attr = 1;
- if (attr.form == DW_FORM_addr
- || attr.form == DW_FORM_GNU_addr_index)
- part_die->highpc = DW_ADDR (&attr);
- else
- {
- high_pc_relative = 1;
- part_die->highpc = DW_UNSND (&attr);
- }
+ part_die->highpc = attr_value_as_address (&attr);
+ if (cu->header.version >= 4 && attr_form_is_constant (&attr))
+ high_pc_relative = 1;
break;
case DW_AT_location:
/* Support the .debug_loc offsets. */
@@ -17464,9 +17471,8 @@ new_symbol_full (struct die_info *die, struct type *type, struct dwarf2_cu *cu,
case DW_TAG_label:
attr = dwarf2_attr (die, DW_AT_low_pc, cu);
if (attr)
- {
- SYMBOL_VALUE_ADDRESS (sym) = DW_ADDR (attr) + baseaddr;
- }
+ SYMBOL_VALUE_ADDRESS (sym)
+ = attr_value_as_address (attr) + baseaddr;
SYMBOL_TYPE (sym) = objfile_type (objfile)->builtin_core_addr;
SYMBOL_DOMAIN (sym) = LABEL_DOMAIN;
SYMBOL_ACLASS_INDEX (sym) = LOC_LABEL;
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S
new file mode 100644
index 0000000..03f9442
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S
@@ -0,0 +1,151 @@
+/* Copyright 2014 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/>. */
+
+ .section .debug_info
+ .4byte .Ledebug_info0 - .Lsdebug_info0 /* Length of Compilation Unit Info */
+.Lsdebug_info0:
+ .2byte 0x2 /* DWARF version number */
+ .4byte .Ldebug_abbrev0 /* Offset Into Abbrev. Section */
+ .byte 0x4 /* Pointer Size (in bytes) */
+ .uleb128 0x1 /* (DIE (0xb) DW_TAG_compile_unit) */
+ .ascii "GNU C 4.7.4 20140206 for GNAT Pro 7.3.0w (20140206)\0"
+ .byte 0x1 /* DW_AT_language */
+ .ascii "dw2-abs-hi-pc-hello.c\0" /* DW_AT_name */
+ .ascii "/tmp\0" /* DW_AT_comp_dir */
+ .4byte .hello_start /* DW_AT_low_pc */
+ .4byte .hello_end /* DW_AT_high_pc */
+ .4byte .Ldebug_line0 /* DW_AT_stmt_list */
+ .uleb128 0x2 /* (DIE (0x2d) DW_TAG_subprogram) */
+ .byte 0x1 /* DW_AT_external */
+ .ascii "hello\0"
+ .byte 0x1 /* DW_AT_decl_file (hello.c) */
+ .byte 0x13 /* DW_AT_decl_line */
+ .byte 0x1 /* DW_AT_prototyped */
+ .4byte .hello_start /* DW_AT_low_pc */
+ .4byte .hello_end /* DW_AT_high_pc */
+ .byte 0 /* end of children of DIE 0xb */
+.Ledebug_info0:
+
+ .section .debug_abbrev
+.Ldebug_abbrev0:
+ .uleb128 0x1 /* (abbrev code) */
+ .uleb128 0x11 /* (TAG: DW_TAG_compile_unit) */
+ .byte 0x1 /* DW_children_yes */
+ .uleb128 0x25 /* (DW_AT_producer) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x13 /* (DW_AT_language) */
+ .uleb128 0xb /* (DW_FORM_data1) */
+ .uleb128 0x3 /* (DW_AT_name) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x1b /* (DW_AT_comp_dir) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x11 /* (DW_AT_low_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .uleb128 0x12 /* (DW_AT_high_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .uleb128 0x10 /* (DW_AT_stmt_list) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .byte 0
+ .byte 0
+ .uleb128 0x2 /* (abbrev code) */
+ .uleb128 0x2e /* (TAG: DW_TAG_subprogram) */
+ .byte 0 /* DW_children_no */
+ .uleb128 0x3f /* (DW_AT_external) */
+ .uleb128 0xc /* (DW_FORM_flag) */
+ .uleb128 0x3 /* (DW_AT_name) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x3a /* (DW_AT_decl_file) */
+ .uleb128 0xb /* (DW_FORM_data1) */
+ .uleb128 0x3b /* (DW_AT_decl_line) */
+ .uleb128 0xb /* (DW_FORM_data1) */
+ .uleb128 0x27 /* (DW_AT_prototyped) */
+ .uleb128 0xc /* (DW_FORM_flag) */
+ .uleb128 0x11 /* (DW_AT_low_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .uleb128 0x12 /* (DW_AT_high_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .byte 0
+ .byte 0
+ .byte 0
+
+ .section .debug_line
+.Ldebug_line0:
+ .4byte LELT-LSLT /* Length of Source Line Info */
+LSLT:
+ .2byte 0x2 /* DWARF Version */
+ .4byte LELTP-LASLTP /* Prolog Length */
+LASLTP:
+ .byte 0x1 /* Minimum Instruction Length */
+ .byte 0x1 /* Default is_stmt_start flag */
+ .byte 0x1 /* Line Base Value (Special Opcodes) */
+ .byte 0x1 /* Line Range Value (Special Opcodes) */
+ .byte 0xd /* Special Opcode Base */
+ .byte 0 /* opcode: 0x1 has 0 args */
+ .byte 0x1 /* opcode: 0x2 has 1 args */
+ .byte 0x1 /* opcode: 0x3 has 1 args */
+ .byte 0x1 /* opcode: 0x4 has 1 args */
+ .byte 0x1 /* opcode: 0x5 has 1 args */
+ .byte 0 /* opcode: 0x6 has 0 args */
+ .byte 0 /* opcode: 0x7 has 0 args */
+ .byte 0 /* opcode: 0x8 has 0 args */
+ .byte 0x1 /* opcode: 0x9 has 1 args */
+ .byte 0 /* opcode: 0xa has 0 args */
+ .byte 0 /* opcode: 0xb has 0 args */
+ .byte 0x1 /* opcode: 0xc has 1 args */
+ .byte 0 /* End directory table */
+ .ascii "dw2-abs-hi-pc-hello.c\0" /* File Entry: 0x1 */
+ .uleb128 0
+ .uleb128 0
+ .uleb128 0
+ .byte 0 /* End file name table */
+LELTP:
+ .byte 0 /* set address to .hello_start */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .hello_start
+ .byte 0x3 /* DW_LNS_advance_line */
+ .sleb128 22 /* ... to 23 */
+ .byte 0x5 /* column 0 */
+ .uleb128 0 /* 0 */
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 0 /* set address to .hello0 */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .hello0
+ .byte 0x3 /* DW_LNS_advance_line */
+ .sleb128 1 /* ... to 24 */
+ .byte 0x5 /* column 0 */
+ .uleb128 0 /* 0 */
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 0 /* set address to .hello1 */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .hello1
+ .byte 0x3 /* DW_LNS_advance_line */
+ .sleb128 1 /* ... to 25 */
+ .byte 0x5 /* column 0 */
+ .uleb128 0 /* 0 */
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 0 /* set address to .hello_end */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .hello_end
+ .byte 0 /* end sequence */
+ .uleb128 0x1
+ .byte 0x1
+LELT:
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c
new file mode 100644
index 0000000..59c761d
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c
@@ -0,0 +1,28 @@
+/* Copyright 2014 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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/>. */
+
+extern int v;
+
+asm (".hello_start: .globl .hello_start\n");
+void
+hello (void)
+{
+asm (".hello0: .globl .hello0\n");
+ v++;
+asm (".hello1: .globl .hello1\n");
+}
+asm (".hello_end: .globl .hello_end\n");
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S
new file mode 100644
index 0000000..c3e89a6
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S
@@ -0,0 +1,151 @@
+/* Copyright 2014 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/>. */
+
+ .section .debug_info
+ .4byte .Ledebug_info0 - .Lsdebug_info0 /* Length of Compilation Unit Info */
+.Lsdebug_info0:
+ .2byte 0x2 /* DWARF version number */
+ .4byte .Ldebug_abbrev0 /* Offset Into Abbrev. Section */
+ .byte 0x4 /* Pointer Size (in bytes) */
+ .uleb128 0x1 /* (DIE (0xb) DW_TAG_compile_unit) */
+ .ascii "GNU C 4.7.4 20140206 for GNAT Pro 7.3.0w (20140206)\0"
+ .byte 0x1 /* DW_AT_language */
+ .ascii "dw2-abs-hi-pc-world.c\0" /* DW_AT_name */
+ .ascii "/tmp\0" /* DW_AT_comp_dir */
+ .4byte .world_start /* DW_AT_low_pc */
+ .4byte .world_end /* DW_AT_high_pc */
+ .4byte .Ldebug_line0 /* DW_AT_stmt_list */
+ .uleb128 0x2 /* (DIE (0x2d) DW_TAG_subprogram) */
+ .byte 0x1 /* DW_AT_external */
+ .ascii "world\0"
+ .byte 0x1 /* DW_AT_decl_file (world.c) */
+ .byte 0x13 /* DW_AT_decl_line */
+ .byte 0x1 /* DW_AT_prototyped */
+ .4byte .world_start /* DW_AT_low_pc */
+ .4byte .world_end /* DW_AT_high_pc */
+ .byte 0 /* end of children of DIE 0xb */
+.Ledebug_info0:
+
+ .section .debug_abbrev
+.Ldebug_abbrev0:
+ .uleb128 0x1 /* (abbrev code) */
+ .uleb128 0x11 /* (TAG: DW_TAG_compile_unit) */
+ .byte 0x1 /* DW_children_yes */
+ .uleb128 0x25 /* (DW_AT_producer) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x13 /* (DW_AT_language) */
+ .uleb128 0xb /* (DW_FORM_data1) */
+ .uleb128 0x3 /* (DW_AT_name) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x1b /* (DW_AT_comp_dir) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x11 /* (DW_AT_low_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .uleb128 0x12 /* (DW_AT_high_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .uleb128 0x10 /* (DW_AT_stmt_list) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .byte 0
+ .byte 0
+ .uleb128 0x2 /* (abbrev code) */
+ .uleb128 0x2e /* (TAG: DW_TAG_subprogram) */
+ .byte 0 /* DW_children_no */
+ .uleb128 0x3f /* (DW_AT_external) */
+ .uleb128 0xc /* (DW_FORM_flag) */
+ .uleb128 0x3 /* (DW_AT_name) */
+ .uleb128 0x8 /* (DW_FORM_string) */
+ .uleb128 0x3a /* (DW_AT_decl_file) */
+ .uleb128 0xb /* (DW_FORM_data1) */
+ .uleb128 0x3b /* (DW_AT_decl_line) */
+ .uleb128 0xb /* (DW_FORM_data1) */
+ .uleb128 0x27 /* (DW_AT_prototyped) */
+ .uleb128 0xc /* (DW_FORM_flag) */
+ .uleb128 0x11 /* (DW_AT_low_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .uleb128 0x12 /* (DW_AT_high_pc) */
+ .uleb128 0x6 /* (DW_FORM_data4) */
+ .byte 0
+ .byte 0
+ .byte 0
+
+ .section .debug_line
+.Ldebug_line0:
+ .4byte LELT-LSLT /* Length of Source Line Info */
+LSLT:
+ .2byte 0x2 /* DWARF Version */
+ .4byte LELTP-LASLTP /* Prolog Length */
+LASLTP:
+ .byte 0x1 /* Minimum Instruction Length */
+ .byte 0x1 /* Default is_stmt_start flag */
+ .byte 0x1 /* Line Base Value (Special Opcodes) */
+ .byte 0x1 /* Line Range Value (Special Opcodes) */
+ .byte 0xd /* Special Opcode Base */
+ .byte 0 /* opcode: 0x1 has 0 args */
+ .byte 0x1 /* opcode: 0x2 has 1 args */
+ .byte 0x1 /* opcode: 0x3 has 1 args */
+ .byte 0x1 /* opcode: 0x4 has 1 args */
+ .byte 0x1 /* opcode: 0x5 has 1 args */
+ .byte 0 /* opcode: 0x6 has 0 args */
+ .byte 0 /* opcode: 0x7 has 0 args */
+ .byte 0 /* opcode: 0x8 has 0 args */
+ .byte 0x1 /* opcode: 0x9 has 1 args */
+ .byte 0 /* opcode: 0xa has 0 args */
+ .byte 0 /* opcode: 0xb has 0 args */
+ .byte 0x1 /* opcode: 0xc has 1 args */
+ .byte 0 /* End directory table */
+ .ascii "dw2-abs-hi-pc-world.c\0" /* File Entry: 0x1 */
+ .uleb128 0
+ .uleb128 0
+ .uleb128 0
+ .byte 0 /* End file name table */
+LELTP:
+ .byte 0 /* set address to .world_start */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .world_start
+ .byte 0x3 /* DW_LNS_advance_line */
+ .sleb128 22 /* ... to 23 */
+ .byte 0x5 /* column 0 */
+ .uleb128 0 /* 0 */
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 0 /* set address to .world0 */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .world0
+ .byte 0x3 /* DW_LNS_advance_line */
+ .sleb128 1 /* ... to 24 */
+ .byte 0x5 /* column 0 */
+ .uleb128 0 /* 0 */
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 0 /* set address to .world1 */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .world1
+ .byte 0x3 /* DW_LNS_advance_line */
+ .sleb128 1 /* ... to 25 */
+ .byte 0x5 /* column 0 */
+ .uleb128 0 /* 0 */
+ .byte 1 /* DW_LNS_copy */
+
+ .byte 0 /* set address to .world_end */
+ .uleb128 0x5
+ .byte 0x2
+ .4byte .world_end
+ .byte 0 /* end sequence */
+ .uleb128 0x1
+ .byte 0x1
+LELT:
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c
new file mode 100644
index 0000000..04f17bd
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c
@@ -0,0 +1,28 @@
+/* Copyright 2014 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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/>. */
+
+extern int v;
+
+asm (".world_start: .globl .world_start\n");
+void
+world (void)
+{
+asm (".world0: .globl .world0\n");
+ v++;
+asm (".world1: .globl .world1\n");
+}
+asm (".world_end: .globl .world_end\n");
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.c b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.c
new file mode 100644
index 0000000..95773a2
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.c
@@ -0,0 +1,28 @@
+/* Copyright 2014 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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/>. */
+
+extern void hello (void);
+extern void world (void);
+
+int v;
+
+int
+main (void)
+{
+ hello ();
+ world ();
+}
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp
new file mode 100644
index 0000000..79f1556
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp
@@ -0,0 +1,36 @@
+# Copyright 2014 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/>.
+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
+set executable ${testfile}
+
+if {[build_executable ${testfile}.exp ${executable} "${testfile}.c ${testfile}-hello-dbg.S ${testfile}-hello.c ${testfile}-world-dbg.S ${testfile}-world.c"] == -1} {
+ return -1
+}
+
+clean_restart $executable
+
+gdb_test "break hello" \
+ "Breakpoint $decimal at $hex: file .*dw2-abs-hi-pc-hello\\.c, line 24\\."
+
+
+gdb_test "break world" \
+ "Breakpoint $decimal at $hex: file .*dw2-abs-hi-pc-world\\.c, line 24\\."
--
1.8.3.2