Commit Graph

114 Commits

Author SHA1 Message Date
James Henderson 1da62b51a5 [DebugInfo] Print version in error message in decimal
Also remove some test duplication and add a test case that shows the
maximum version is rejected (this also shows that the value in the error
message is actually in decimal, and not just missing an 0x prefix).

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D74403
2020-02-12 14:49:22 +00:00
Sterling Augustine 417375d785 Allow retrieving source files relative to the compilation directory.
Summary:
Dwarf stores source-file names the three parts:
<compilation_directory><include_directory><filename>

Prior to this change, the code only allowed retrieving either all
three as the absolute path, or just the filename.  But many
compile-command lines--especially those in hermetic build systems
don't specify an absolute path, nor just the filename, but rather the
path relative to the compilation directory. This features allows
retrieving them in that style.

Add tests for path printing styles.

Modify createBasicPrologue to handle include directories.

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73383
2020-02-11 11:46:20 -08:00
Alexey Lapshin cc9b4fb6c9 [Debuginfo][NFC] Rename error handling functions using the same pattern.
Summary:
That patch is extracted from https://reviews.llvm.org/D74308.
Currently there are two patterns to name error handling functions:
using "Callback" and "Handler". This patch uses "Handler" for all
usage places.

Reviewers: jhenderson, dblaikie, probinson, aprantl

Reviewed By: jhenderson, dblaikie

Subscribers: hiraditya, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D74354
2020-02-11 14:50:53 +03:00
Bill Wendling c55cf4afa9 Revert "Remove redundant "std::move"s in return statements"
The build failed with

  error: call to deleted constructor of 'llvm::Error'

errors.

This reverts commit 1c2241a793.
2020-02-10 07:07:40 -08:00
James Henderson b1c7bfe6da [DebugInfo] Reject line tables of version > 5
If a debug line section with version of greater than 5 is encountered,
prior to this change the parser would accept it and treat it as version
5. This might work to some extent, but then it might not at all, as it
really depends on the format of the unspecified future version, which
will be different (otherwise there would be no point in changing the
version number). Any information we could provide has a good chance of
being invalid, so we should just refuse to parse such tables.

Reviewed by: dblaikie, MaskRay

Differential Revision: https://reviews.llvm.org/D74204
2020-02-10 14:43:10 +00:00
Bill Wendling 1c2241a793 Remove redundant "std::move"s in return statements 2020-02-10 06:39:44 -08:00
James Henderson 021f531786 [DebugInfo] Fix DebugLine::Prologue::getLength
The function a) returned 32-bits when in DWARF64, the PrologueLength
field is 64-bits in size, and b) didn't work for DWARF version 5.

Also deleted some related dead code. With this deletion, getLength is
itself dead, but another change is about to make use of it.

Reviewed by: probinson

Differential Revision: https://reviews.llvm.org/D73626
2020-01-30 09:35:50 +00:00
Sterling Augustine 0758ac4e0c Handle non-absolute include dirs properly for both dwarf4 and dwarf5.
Summary:
Add test case for the same. This test case will also serve as a
starting point for later symbolizer tests.

Reviewers: dblaikie, jdoerfert

Subscribers: hiraditya, llvm-commits, jhenderson

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73583
2020-01-29 10:51:51 -08:00
James Henderson 7116e431c0 [DebugInfo] Make most debug line prologue errors non-fatal to parsing
Many of the debug line prologue errors are not inherently fatal. In most
cases, we can make reasonable assumptions and carry on. This patch does
exactly that. In the case of length problems, the approach of "assume
stated length is correct" is taken which means the offset might need
adjusting.

This is a relanding of b94191fe, fixing an LLD test and the LLDB build.

Reviewed by: dblaikie, labath

Differential Revision: https://reviews.llvm.org/D72158
2020-01-29 10:23:41 +00:00
Benjamin Kramer adcd026838 Make llvm::StringRef to std::string conversions explicit.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.

This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.

This doesn't actually modify StringRef yet, I'll do that in a follow-up.
2020-01-28 23:25:25 +01:00
James Henderson 5c05165984 Revert "[DebugInfo] Make most debug line prologue errors non-fatal to parsing"
This reverts commit b94191fecd.

The change broke both an LLD test and the LLDB build.
2020-01-28 11:49:30 +00:00
James Henderson b94191fecd [DebugInfo] Make most debug line prologue errors non-fatal to parsing
Many of the debug line prologue errors are not inherently fatal. In most
cases, we can make reasonable assumptions and carry on. This patch does
exactly that. In the case of length problems, the approach of "the
claimed length is correct" is taken to be consistent with other
instances such as the SectionParser, which ignores the read length.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72158
2020-01-28 11:29:50 +00:00
James Henderson f1be770ff6 [DebugInfo] Make incorrect debug line extended opcode length non-fatal
It is possible to try to keep parsing a debug line program even when the
length of an extended opcode does not match what is expected for that
opcode. This patch changes what was previously a fatal error to be
non-fatal. The parser now continues by assuming the the claimed length
is correct, even if it means moving the offset backwards.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72155
2020-01-27 15:32:41 +00:00
Hubert Tong 63b428e386 DWARFDebugLine.cpp: Format unknown line number standard opcodes
Summary:
This patch implements `formatv()` formatting for `dwarf::LineNumberOps`
and makes use of it for the `llvm-dwarfdump --debug-line` dump.

Previously, unknown line number standard opcodes would lead to undefined
behaviour. The code would attempt to format the data pointer of an empty
`StringRef` (a null pointer) using `%s`. According to the description
for `format()`, use of that interface carries the "risk of `printf`".
Passing a null pointer in place of an array to a C library function
results in undefined behaviour.

Reviewers: jhenderson, daltenty, stevewan

Reviewed By: jhenderson

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72369
2020-01-15 10:45:50 -05:00
Hubert Tong aca3e70d2b DWARFDebugLine.cpp: Restore LF line endings
rG7e02406f6cf180a8c89ce64665660e7cc9dbc23e switched the file to CRLF
line endings.
2020-01-14 21:23:39 -05:00
James Henderson 07804f75a6 [DebugInfo] Make debug line address size mismatch non-fatal to parsing
Reasonable assumptions can be made when a parsed address length does not
match the expected length, so there's no need for this to be fatal.

Reviewed by: ikudrin

Differential Revision: https://reviews.llvm.org/D72154
2020-01-13 16:27:05 +00:00
James Henderson 7e02406f6c [DebugInfo][NFC] Remove unused variable/fix variable naming
Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D72159
2020-01-10 15:00:56 +00:00
James Henderson 6e3ca962fa [DebugInfo] Improve error message text
Unlike most of our errors in the debug line parser, the "no end of
sequence" message was missing any reference to which line table it
refererred to. This change adds the offset to this message.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D72443
2020-01-10 14:59:58 +00:00
James Henderson 216796f234 [DebugInfo] Fix infinite loop caused by reading past debug_line end
If the claimed unit length of a debug line program is such that the line
table would finish past the end of the .debug_line section, an infinite
loop occurs because the data extractor will continue to "read" zeroes
without changing the offset. This previously didn't hit an error because
the line table program handles a series of zeroes as a bad extended
opcode.

This patch fixes the inifinite loop and adds a warning if the program
doesn't fit in the available data.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D72279
2020-01-07 10:22:35 +00:00
James Henderson d68904f957 [NFC] Fix trivial typos in comments
Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D72143

Patch by Kazuaki Ishizaki.
2020-01-06 10:50:26 +00:00
Jonas Devlieghere c75aac42a6 [DWARF] Don't assume optional always has a value.
When getting the file name form the line table prologue we assume that a
valid string form value can always be extracted as a string. If you look
at the implementation of DWARFormValue this is not necessarily true. I
hit this assertion from LLDB when I create a "dummy" DWARFContext that
was missing the string section.
2020-01-03 09:53:44 -08:00
James Henderson 418cd8216b [DebugInfo] Remove redundant checks for past-the-end of prologue
The V5 directory and filename tables had checks in to make sure we
hadn't read past the end of the line table prologue. Since previous
changes to the data extractor class ensure we never read past the end,
these checks are now redundant, so this patch removes them.

There is still a check to show that the whole prologue remains within
the prologue length.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71768
2020-01-03 12:35:32 +00:00
James Henderson bd402fc3f3 [DebugInfo][NFC] Use function_ref consistently in debug line parsing
This patch fixes an inconsistency where we were using std::function in
some places and function_ref in others to pass around the error handling
callback.

Reviewed by: MaskRay

Differential Revision: https://reviews.llvm.org/D71762
2020-01-02 18:01:54 +00:00
James Henderson 60cb33c9b8 [DebugInfo] Fix verbose printing of rows added via DW_LNE_end_sequence
The debug line verbose printing was printing the wrong values for rows
added via DW_LNE_end_sequence, because the row was being printed AFTER
its state had been reset following it being appended to the line table.
This patch fixes this issue by printing the row before appending it.

Reviewers: dblaikie, MaskRay

Differential Revision: https://reviews.llvm.org/D71664
2019-12-19 12:54:04 +00:00
James Henderson 5666b70fd0 [DebugInfo] Only print a single blank line after an empty line table
Commit 84a9756 added an extra blank line at the end of any line table.
However, a blank line is also printed after the line table header, which
meant that two blank lines in a row were being printed after a header,
if there were no rows. This patch defers the post-header blank line
printing until it has been determined that there are rows to print.

Reviewed by: dblaikie

Differential Revision: https://reviews.llvm.org/D71540
2019-12-17 12:04:09 +00:00
James Henderson 84a9756a72 [llvm-dwarfdump] Add blank line after printing line table
This helps delineate it in the output from later tables or other output.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D71344
2019-12-12 14:06:10 +00:00
James Henderson 2f8155023a [DebugInfo] Fix printing of DW_LNS_set_isa
The Isa register is a uint8_t, but at least on Windows this is
internally an unsigned char, which meant that prior to this patch it got
formatted as an ASCII character, rather than a decimal number. This
patch fixes this by casting it to a uint64_t before printing. I did it
this way instead of using a uint8_t formatter because a) it is simpler,
and b) it allows us to change the internal type of Isa in the future
without this code breaking.

I also took the opportunity to test the printing of the other standard
opcodes.

Reviewed by: probinson

Differential Revision: https://reviews.llvm.org/D71274
2019-12-11 13:38:41 +00:00
Jonas Devlieghere de0ce98abe [DebugLine] Don't try to guess the path style
In r368879 I made an attempt to guess the path style from the files in
the line table. After some consideration I now think this is a poor
idea. This patch undoes that behavior and instead adds an optional
argument to specify the path style. This allows us to make that decision
elsewhere where we have more information. In case of LLDB based on the
Unit.

llvm-svn: 369072
2019-08-15 23:53:15 +00:00
Jonas Devlieghere c0a9b1edca [DebugLine] Improve path handling.
After switching over LLDB's line table parser to libDebugInfo, we
noticed two regressions on the Windows bot. The problem is that when
obtaining a file from the line table prologue, we append paths without
specifying a path style. This leads to incorrect results on Windows for
debug info containing Posix paths:

  0x0000000000201000: /tmp\b.c, is_start_of_statement = TRUE

This patch is an attempt to fix that by guessing the path style whenever
possible.

Differential revision: https://reviews.llvm.org/D66227

llvm-svn: 368879
2019-08-14 17:00:10 +00:00
Igor Kudrin f26a70a5e7 Switch LLVM to use 64-bit offsets (2/5)
This updates all libraries and tools in LLVM Core to use 64-bit offsets
which directly or indirectly come to DataExtractor.

Differential Revision: https://reviews.llvm.org/D65638

llvm-svn: 368014
2019-08-06 10:49:40 +00:00
Igor Kudrin 3daefb0744 [DWARF][NFC] Add constants for reserved values of an initial length field.
Differential Revision: https://reviews.llvm.org/D65039

llvm-svn: 366887
2019-07-24 11:34:29 +00:00
Jonas Devlieghere f8552e67e9 [DWARF] Use 32-bit format specifier for offset
This should fix PR42730.

llvm-svn: 366859
2019-07-23 22:34:21 +00:00
Jonas Devlieghere 0e7ba06e82 [DWARF] Add more error handling to debug line parser.
This patch exnteds the error handling in the debug line parser to get
rid of the existing MD5 assertion. I want to reuse the debug line parser
from LLVM in LLDB where we cannot crash on invalid input.

Differential revision: https://reviews.llvm.org/D64544

llvm-svn: 366762
2019-07-22 23:23:34 +00:00
Alex Bradbury 44deaf7e54 [DWARF][RISCV] Add support for RISC-V relocations needed for debug info
When code relaxation is enabled many RISC-V fixups are not resolved but
instead relocations are emitted. This happens even for DWARF debug
sections. Therefore, to properly support the parsing of DWARF debug info
we need to be able to resolve RISC-V relocations. This patch adds:

* Support for RISC-V relocations in RelocationResolver
* DWARF support for two relocations per object file offset
* DWARF changes to support relocations in more DIE fields

The two relocations per offset change is needed because some RISC-V
relocations (used for label differences) come in pairs.

Relocations can also be emitted for DWARF fields where relocations were
not yet evaluated. Adding relocation support for some of these fields is
essencial. On the other hand, LLVM currently emits RISC-V relocations
for fixups that could be safely evaluated, since they can never be
affected by code relaxations. This patch also adds relocation support
for the fields affected by those extraneous relocations (the DWARF unit
entry Length, and the DWARF debug line entry TotalLength and
PrologueLength), for testing purposes.

Differential Revision: https://reviews.llvm.org/D62062
Patch by Luís Marques.

llvm-svn: 366402
2019-07-18 05:22:55 +00:00
Igor Kudrin f48bc01812 [DWARF] Fix the reserved values for unit length in DWARFDebugLine.
The DWARF3 documentation had inconsistency concerning the reserved range
for unit length values. The issue was fixed in DWARF4.

Differential Revision: https://reviews.llvm.org/D64622

llvm-svn: 366190
2019-07-16 07:01:08 +00:00
Igor Kudrin 74c350af21 [DWARF] Fix an incorrect format specifier.
This adjusts the format specifier because PCOffset is uint16_t.

Differential Revision: https://reviews.llvm.org/D64620

llvm-svn: 366189
2019-07-16 06:56:10 +00:00
Jonas Devlieghere ca16d280f7 Re-land "[DebugInfo] Move function from line table to the prologue (NFC)"
In LLDB, when parsing type units, we don't need to parse the whole line
table. Instead, we only need to parse the "support files" from the line
table prologue.

To make that possible, this patch moves the respective functions from
the LineTable into the Prologue. Because I don't think users of the
LineTable should have to know that these files come from the Prologue,

I've left the original methods in place, and made them redirect to the
LineTable.

Differential revision: https://reviews.llvm.org/D64774

llvm-svn: 366164
2019-07-16 01:21:25 +00:00
Jonas Devlieghere 01ee172e9e Revert "[DebugInfo] Move function from line table to the prologue (NFC)"
This broke LLD, which I didn't have enabled.

llvm-svn: 366160
2019-07-16 00:59:04 +00:00
Jonas Devlieghere 509903e887 [DebugInfo] Move function from line table to the prologue (NFC)
In LLDB, when parsing type units, we don't need to parse the whole line
table. Instead, we only need to parse the "support files" from the line
table prologue.

To make that possible, this patch moves the respective functions from
the LineTable into the Prologue. Because I don't think users of the
LineTable should have to know that these files come from the Prologue,

I've left the original methods in place, and made them redirect to the
LineTable.

Differential revision: https://reviews.llvm.org/D64774

llvm-svn: 366158
2019-07-16 00:37:17 +00:00
Fangrui Song 7e55672b22 DWARF v5: fix directory index in the line table
Summary:
Prior to DWARF v5, a directory index of 0 represents DW_AT_comp_dir.

In DWARF v5, the index starts with 0 and Entry.DirIdx is the index into
Prologue.IncludeDirectories.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D61253

llvm-svn: 360015
2019-05-06 08:03:46 +00:00
Fangrui Song cc1fec31d9 [DWARF] Delete a redundant check in getFileNameByIndex()
llvm-svn: 359422
2019-04-29 08:15:13 +00:00
Fangrui Song 3153764c88 s/Dwarf 5/DWARF v5/ NFC
llvm-svn: 359307
2019-04-26 13:41:19 +00:00
Ali Tamur 783d84bb39 [llvm] Prevent duplicate files in debug line header in dwarf 5: another attempt
Another attempt to land the changes in debug line header to prevent duplicate
files in Dwarf 5. I rolled back my previous commit because of a mistake in
generating the object file in a test. Meanwhile, I addressed some offline
comments and changed the implementation; the largest difference is that
MCDwarfLineTableHeader does not keep DwarfVersion but gets it as a parameter. I
also merged the patch to fix two lld tests that will strt to fail into this
patch.

Original Commit:

https://reviews.llvm.org/D59515

Original Message:
Motivation: In previous dwarf versions, file name indexes started from 1, and
the primary source file was not explicit. Dwarf 5 standard (6.2.4) prescribes
the primary source file to be explicitly given an entry with an index number 0.

The current implementation honors the specification by just duplicating the
main source file, once with index number 0, and later maybe with another
index number. While this is compliant with the letter of the standard, the
duplication causes problems for consumers of this information such as lldb.
(Some files are duplicated, where only some of them have a line table although
all refer to the same file)

With this change, dwarf 5 debug line section files always start from 0, and
the zeroth entry is not duplicated whenever possible. This requires different
handling of dwarf 4 and dwarf 5 during generation (e.g. when a function returns
an index zero for a file name, it signals an error in dwarf 4, but not in dwarf
5) However, I think the minor complication is worth it, because it enables all
consumers (lldb, gdb, dwarfdump, objdump, and so on) to treat all files in the
file name list homogenously.

llvm-svn: 358732
2019-04-19 02:26:56 +00:00
Fangrui Song 50a09670f0 [DWARF] Make DWARFDebugLine::ParsingState::RowNumber a local variable
llvm-svn: 358374
2019-04-15 07:40:30 +00:00
Fangrui Song 6a285dfe71 [DWARF] Set discriminator to 0 for DW_LNS_copy
Summary:
Make DW_LNS_copy set the discriminator register to 0, to conform to
DWARF 4 & 5: "Then it sets the discriminator register to 0, and sets the
basic_block, prologue_end and epilogue_begin registers to false."

Because all of DW_LNE_end_sequence, DN_LNS_copy, and special opcodes reset
discriminator to 0, we can move discriminator=0 to appendRowToMatrix.

Also, make DW_LNS_copy print before appending the row, as it is similar
to a address+=0,line+=0 special opcode, which prints before appending
the row.

Reviewers: dblaikie, probinson, aprantl

Reviewed By: dblaikie

Subscribers: danielcdh, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60364

llvm-svn: 358148
2019-04-11 02:02:44 +00:00
Fangrui Song b3be23d334 [DWARF] Simplify LineTable::findRowInSeq
We want the last row whose address is less than or equal to Address.
This can be computed as upper_bound - 1, which is simpler than
lower_bound followed by skipping equal rows in a loop.

Since FirstRow (LowPC) does not satisfy the predicate (OrderByAddress)
while LastRow-1 (HighPC) satisfies the predicate. We can decrease the
search range by two, i.e.

upper_bound [FirstRow,LastRow) = upper_bound [FirstRow+1,LastRow-1)

llvm-svn: 358053
2019-04-10 07:44:23 +00:00
Fangrui Song 9b22c469ca [DWARF] DWARFDebugLine: replace Sequence::orderByLowPC with orderByHighPC
In a sorted list of non-overlapping [LowPC,HighPC) ranges, locating an address with
upper_bound on HighPC is simpler than lower_bound on LowPC.

llvm-svn: 358012
2019-04-09 15:08:32 +00:00
Fangrui Song c4c8bcaeec [DWARF] DWARFDebugLine: delete unused parameter `Offset`
llvm-svn: 357866
2019-04-07 13:56:14 +00:00
Ali Tamur 02e96648d7 Revert "[llvm] Reapply "Prevent duplicate files in debug line header in dwarf 5.""
This reverts commit rL357020.

The commit broke the test llvm/test/tools/llvm-objdump/embedded-source.test
on some builds including clang-ppc64be-linux-multistage,
clang-s390x-linux, clang-with-lto-ubuntu, clang-x64-windows-msvc,
llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast (and others).

llvm-svn: 357026
2019-03-26 20:05:27 +00:00
Ali Tamur 2f5cd03a3f [llvm] Reapply "Prevent duplicate files in debug line header in dwarf 5."
Reapply rL356941 after regenerating the object file in the failing test
llvm/test/tools/llvm-objdump/embedded-source.test from source.

Original commit message:

[llvm] Prevent duplicate files in debug line header in dwarf 5.

Motivation: In previous dwarf versions, file name indexes started from 1, and
the primary source file was not explicit. Dwarf 5 standard (6.2.4) prescribes
the primary source file to be explicitly given an entry with an index number 0.

The current implementation honors the specification by just duplicating the
main source file, once with index number 0, and later maybe with another
index number. While this is compliant with the letter of the standard, the
duplication causes problems for consumers of this information such as lldb.
(Some files are duplicated, where only some of them have a line table although
all refer to the same file)

With this change, dwarf 5 debug line section files always start from 0, and
the zeroth entry is not duplicated whenever possible. This requires different
handling of dwarf 4 and dwarf 5 during generation (e.g. when a function returns
an index zero for a file name, it signals an error in dwarf 4, but not in dwarf 5)
However, I think the minor complication is worth it, because it enables all
consumers (lldb, gdb, dwarfdump, objdump, and so on) to treat all files in the
file name list homogenously.

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D59515

llvm-svn: 357018
2019-03-26 18:53:23 +00:00