Commit Graph

94 Commits

Author SHA1 Message Date
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
Ali Tamur fdce82a814 Revert "[llvm] Prevent duplicate files in debug line header in dwarf 5."
This reverts commit 312ab05887.

My commit broke the build; I will revert and find out what happened.

llvm-svn: 356951
2019-03-25 21:09:07 +00:00
Ali Tamur 312ab05887 [llvm] Prevent duplicate files in debug line header in dwarf 5.
Summary:

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.

Reviewers: dblaikie, probinson, aprantl, espindola

Reviewed By: probinson

Subscribers: emaste, jvesely, nhaehnle, aprantl, javed.absar, arichardson, hiraditya, MaskRay, rupprecht, jdoerfert, llvm-commits

Tags: #llvm, #debug-info

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

llvm-svn: 356941
2019-03-25 20:08:00 +00:00
Mircea Trofin 2c3ab66539 [llvm] Skip over empty line table entries.
Summary:
This is similar to how addr2line handles consecutive entries with the
same address - pick the last one.

Reviewers: dblaikie, friss, JDevlieghere

Reviewed By: dblaikie

Subscribers: eugenis, vitalybuka, echristo, JDevlieghere, probinson, aprantl, hiraditya, rupprecht, jdoerfert, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D58952

llvm-svn: 356265
2019-03-15 15:00:12 +00:00
Evgeniy Stepanov 6e64a14804 Revert "[llvm] Skip over empty line table entries."
This reverts commit r355972.
See the discussion at https://reviews.llvm.org/D58952.

llvm-svn: 356001
2019-03-13 01:37:58 +00:00
Mircea Trofin 0c29402eb4 [llvm] Skip over empty line table entries.
Summary:
This is similar to how addr2line handles consecutive entries with the
same address - pick the last one.

Reviewers: dblaikie, friss, JDevlieghere

Reviewed By: dblaikie

Subscribers: ormris, echristo, JDevlieghere, probinson, aprantl, hiraditya, rupprecht, jdoerfert, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D58952

llvm-svn: 355972
2019-03-12 20:48:45 +00:00
Vlad Tsyrklevich 53a9f1d367 Revert "[DWARFFormValue] Cleanup DWARFFormValue interface. (2/2) (NFC)"
This reverts commit r355233, it was causing UBSan failures.

llvm-svn: 355255
2019-03-02 01:10:00 +00:00
Jonas Devlieghere 2dc2baa8cc [DWARFFormValue] Cleanup DWARFFormValue interface. (2/2) (NFC)
Continues the work started in r354941. Changes (all but one) uses of the
extractValue to static createFromData.

llvm-svn: 355233
2019-03-01 22:14:24 +00:00
Alexey Lapshin 77fc1f6049 [DebugInfo] add SectionedAddress to DebugInfo interfaces.
That patch is the fix for https://bugs.llvm.org/show_bug.cgi?id=40703
   "wrong line number info for obj file compiled with -ffunction-sections"
   bug. The problem happened with only .o files. If object file contains
   several .text sections then line number information showed incorrectly.
   The reason for this is that DwarfLineTable could not detect section which
   corresponds to specified address(because address is the local to the
   section). And as the result it could not select proper sequence in the
   line table. The fix is to pass SectionIndex with the address. So that it
   would be possible to differentiate addresses from various sections. With
   this fix llvm-objdump shows correct line numbers for disassembled code.

   Differential review: https://reviews.llvm.org/D58194

llvm-svn: 354972
2019-02-27 13:17:36 +00:00
Jonas Devlieghere bb111152b7 [DWARFFormValue] Cleanup DWARFFormValue interface. (NFC)
DWARFFormValues can be created from a data extractor or by passing its
value directly. Until now this was done by member functions that
modified an existing object's internal state. This patch replaces a
subset of these methods with static method that return a new
DWARFFormValue.

llvm-svn: 354941
2019-02-27 00:58:09 +00:00
James Henderson b6b5b1a592 [DebugInfo]Print correct value for special opcode address increment
The wrong variable was being used when printing the address increment in
verbose output of .debug_line. This patch fixes this.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D57693

llvm-svn: 353288
2019-02-06 10:31:50 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Fangrui Song 0cac726a00 llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...)
Summary: The convenience wrapper in STLExtras is available since rL342102.

Reviewers: dblaikie, javed.absar, JDevlieghere, andreadb

Subscribers: MatzeB, sanjoy, arsenm, dschuff, mehdi_amini, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, javed.absar, gbedwell, jrtc27, mgrang, atanasyan, steven_wu, george.burgess.iv, dexonsmith, kristina, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D52573

llvm-svn: 343163
2018-09-27 02:13:45 +00:00
Victor Leschuk cf1f714d3b [DWARF] Unify warning callbacks. NFC.
Both DWARFDebugLine and DWARFDebugAddr used the same callback mechanism
for handling recoverable errors. They both implemented similar warn() function
to be used as such callbacks.

In this revision we get rid of code duplication and move this warn() function
to DWARFContext as DWARFContext::dumpWarning().

Reviewers: lhames, jhenderson, aprantl, probinson, dblaikie, JDevlieghere

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D51033

llvm-svn: 340528
2018-08-23 12:43:33 +00:00
Victor Leschuk cba595da82 [DWARF] Refactor DWARF classes to use unified error reporting. NFC.
DWARF-related classes in lib/DebugInfo/DWARF contained 
duplicating code for creating StringError instances, like:

template <typename... Ts>
static Error createError(char const *Fmt, const Ts &... Vals) {
  std::string Buffer;
  raw_string_ostream Stream(Buffer);
  Stream << format(Fmt, Vals...);
  return make_error<StringError>(Stream.str(), inconvertibleErrorCode());
}

Similar function was placed in Support lib in https://reviews.llvm.org/D49824

This revision makes DWARF classes use this function
instead of their local implementation of it.

Reviewers: aprantl, dblaikie, probinson, wolfgangp, JDevlieghere, jhenderson

Reviewed By: JDevlieghere, jhenderson

Differential Revision: https://reviews.llvm.org/D49964

llvm-svn: 340163
2018-08-20 09:59:08 +00:00
Paul Robinson 7f33094486 [DebugInfo/DWARF] [2/4] Type units no longer in a std::deque. NFC
This is patch 2 of 4 NFC refactorings to handle type units and compile
units more consistently and with less concern about the object-file
section that they came from.

Patch 2 takes the existing std::deque<DWARFUnitSection> for type units
and makes it a simple DWARFUnitSection, simplifying the handling of
type units and making it more consistent with compile units.

Differential Revision: https://reviews.llvm.org/D49742

llvm-svn: 338629
2018-08-01 20:46:46 +00:00
James Henderson 004b729ed1 [DWARF] Refactor callback usage for .debug_line error handling
Change the "recoverable" error callback to take an Error instaed of a
string.

Reviewed by: JDevlieghere

Differential Revision: https://reviews.llvm.org/D46831

llvm-svn: 332845
2018-05-21 15:30:54 +00:00
James Henderson 11a9de74c9 Fix signed/unsigned comparison warning and print format
The print format was causing at least 2 unit-test failures from r331971.

The signed/unsigned comparison warnings only appeared to affect two lines but
it was unclear whether it might just pop up on other lines, so I have been
explicit in all the literals in the tests.

There were other bot unit-test failures that I am still investigating.

llvm-svn: 331978
2018-05-10 12:15:43 +00:00
James Henderson a3acf99e59 [DWARF] Rework debug line parsing to use llvm::Error and callbacks
Reviewed by: dblaikie, JDevlieghere, espindola

Differential Revision: https://reviews.llvm.org/D44560

Summary:
The .debug_line parser previously reported errors by printing to stderr and
return false. This is not particularly helpful for clients of the library code,
as it prevents them from handling the errors in a manner based on the calling
context. This change switches to using llvm::Error and callbacks to indicate
what problems were detected during parsing, and has updated clients to handle
the errors in a location-specific manner. In general, this means that they
continue to do the same thing to external users. Below, I have outlined what
the known behaviour changes are, relating to this change.

There are two levels of "errors" in the new error mechanism, to broadly
distinguish between different fail states of the parser, since not every
failure will prevent parsing of the unit, or of subsequent unit. Malformed
table errors that prevent reading the remainder of the table (reported by
returning them) and other minor issues representing problems with parsing that
do not prevent attempting to continue reading the table (reported by calling a
specified callback funciton). The only example of this currently is when the
last sequence of a unit is unterminated. However, I think it would be good to
change the handling of unrecognised opcodes to report as minor issues as well,
rather than just printing to the stream if --verbose is used (this would be a
subsequent change however).

I have substantially extended the DwarfGenerator to be able to handle
custom-crafted .debug_line sections, allowing for comprehensive unit-testing
of the parser code. For now, I am just adding unit tests to cover the basic
error reporting, and positive cases, and do not currently intend to test every
part of the parser, although the framework should be sufficient to do so at a
later point.

Known behaviour changes:
  - The dump function in DWARFContext now does not attempt to read subsequent
  tables when searching for a specific offset, if the unit length field of a
  table before the specified offset is a reserved value.
  - getOrParseLineTable now returns a useful Error if an invalid offset is
  encountered, rather than simply a nullptr.
  - The parse functions no longer use `WithColor::warning` directly to report
  errors, allowing LLD to call its own warning function.
  - The existing parse error messages have been updated to not specifically
  include "warning" in their message, allowing consumers to determine what
  severity the problem is.
  - If the line table version field appears to have a value less than 2, an
  informative error is returned, instead of just false.
  - If the line table unit length field uses a reserved value, an informative
  error is returned, instead of just false.
  - Dumping of .debug_line.dwo sections is now implemented the same as regular
  .debug_line sections.
  - Verbose dumping of .debug_line[.dwo] sections now prints the prologue, if
  there is a prologue error, just like non-verbose dumping.

As a helper for the generator code, I have re-added emitInt64 to the
AsmPrinter code. This previously existed, but was removed way back in r100296,
presumably because it was dead at the time.

This change also requires a change to LLD, which will be committed separately.

llvm-svn: 331971
2018-05-10 10:51:33 +00:00
Andrew Ng 7a2fa74ab0 [DebugInfo] Use WithColor for more debug line warnings
Updated two more debug line related warnings to use WithColor. This was
necessary to ensure consistent output order of the warnings on Windows
for debug line tests.

Differential Revision: https://reviews.llvm.org/D45871

llvm-svn: 330440
2018-04-20 15:29:47 +00:00
Jonas Devlieghere 84e99265d6 [DebugInfo] Use WithColor to print errors/warnings
Use the convenience methods from WithColor to consistently print errors
and warnings in libDebugInfo.

llvm-svn: 330092
2018-04-14 22:07:23 +00:00