This patch implements the .debug_rnglists section. We are able to
produce the .debug_rnglists section by the following syntax.
```
debug_rnglists:
- Format: DWARF32 ## Optional
Length: 0x1234 ## Optional
Version: 5 ## Optional
AddressSize: 0x08 ## Optional
SegmentSelectorSize: 0x00 ## Optional
OffsetEntryCount: 2 ## Optional
Offsets: [1, 2] ## Optional
Lists:
- Entries:
- Operator: DW_RLE_base_address
Values: [ 0x1234 ]
```
The generated .debug_rnglists is verified by llvm-dwarfdump, except for
the operator DW_RLE_startx_endx, since llvm-dwarfdump doesn't support
it.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D83624
This rewrites the mips-abiflags.test to stop using recompiled objects,
adds testing for all missed bits and also adds two missing enum values
to lib/ObjectYAML, which are used in the new test.
Differential revision: https://reviews.llvm.org/D83954
This patch helps add support for emitting the .debug_str_offsets section
to yaml2elf.
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D83853
When setting the NoHeaders to false,
the e_shnum field wasn't set correctly.
This patch fixes this bug.
Differential revision: https://reviews.llvm.org/D83941
In D83482 we agreed to name e_* fields that are used for overriding
values (like e_phoff) as EPh* (e.g. EPhOff).
Currently we have a set of e_sh* fields that are named inconsistently
with this rule. This patch renames all of them.
Differential revision: https://reviews.llvm.org/D83766
Imagine we have an YAML description for some object and we want to
produce 2 outputs: with and without the section header.
A natural way to do it would look like:
```
--- !ELF
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
Type: ET_REL
Machine: EM_X86_64
Sections:
...
SectionHeaderTable:
NoHeaders: [[NOHEADERS]]
```
But currently, we do not distinguish between no `NoHeaders` key case
and `NoHeaders == false`. Because of this we can't simply specify
`NOHEADERS = false`, as tool starts to complain.
With this patch the behavior changed. When we have:
```
SectionHeaderTable:
NoHeaders: false
```
it is the same as we have no `SectionHeaderTable` at all.
(`NoHeaders` key still can't be used with `Sections/Excluded` keys)
Differential revision: https://reviews.llvm.org/D83672
This patch adds support for emitting value forms of DW_FORM_strx,
DW_FORM_addrx, DW_FORM_loclistx and DW_FORM_rnglistx.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D83749
This adds `EPhOff`, `EPhEntSize` and `EPhNum` keys.
Will be useful for creating broken objects for testing llvm-readelf.
Differential revision: https://reviews.llvm.org/D83482
Functions in DWARFYML::FixupVisitor are declared as
virtual functions in its base class DWARFYAML::Visitor.
We should use the mordern "override" keyword instead
of "virtual" for virtual functions in subclasses for
better safety.
Besides, the visibility is changed from private to
protected to make it consistent with
DWARFYAML::FixupVisitor class and DWARFYAML::Visitor
class.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D83452
This patch helps add support for emitting the .debug_gnu_pubnames and .debug_gnu_pubtypes sections.
The .debug_gnu_pub* sections is verified by llvm-dwarfdump.
Known issues:
- Doesn't support emitting multiple pub-tables.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82367
This patch helps add the missing context `IsGNUStyle`. Before this patch, yaml2obj cannot parse the YAML description of 'debug_gnu_pubnames' and 'debug_gnu_pubtypes' correctly due to the missing context.
In other words, if we have
```
DWARF:
debug_gnu_pubtypes:
Length:
TotalLength: 0x1234
Version: 2
UnitOffset: 0x1234
UnitSize: 0x4321
Entries:
- DieOffset: 0x12345678
Name: abc
Descriptor: 0x00 ## Descriptor can never be mapped into Entry.Descriptor
```
yaml2obj will complain that "error: unknown key 'Descriptor'".
This patch helps resolve this problem.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82435
The abbreviations for a given compilation unit end with an entry
consisting of a 0 byte for the abbreviation code.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82933
'InitialLength' is replaced with 'Format' (DWARF32 by default) and 'Length' in this patch.
Besides, test cases for DWARFv4 and DWARFv5, DWARF32 and DWARF64 is
added.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82622
Before this patch, the diagnostic message is printed to `errs()` directly, which makes it difficult to use `FailedWithMessage()` in unit testing.
In this patch, we add a custom error handler for YAMLParser, which helps collect diagnostic messages and make it easy to use `FailedWithMessage()` to check error messages.
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D82630
This patch helps teach yaml2obj emit correct DWARF64 unit header of the .debug_info section.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82621
The 'Descriptor' field of .debug_gnu_pubnames and .debug_gnu_pubtypes
section should be 1-byte rather than 4-byte. This patch helps resolve
this issue.
This patch helps add support for emitting the .debug_pubnames section to yaml2elf.
Known issues:
- Current implementation doesn't support emitting multiple sets of entries.
- Doesn't support DWARF64.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82296
This patch helps add support for error handling in `DWARFYAML::emitDebugInfo()`.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82275
Before this patch, we use `(uint32_t)AbbrCode - (uint32_t)FirstAbbrCode` to index the abbreviation. It's impossible for we to use the preceeding abbreviation of the previous one (e.g., if the previous DIE's `AbbrCode` is 2, we are unable to use the abbreviation with index 1). In this patch, we use `AbbrCode` to index the abbreviation directly.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D82173
This patch helps add support for emitting the .debug_info section to yaml2elf.
Reviewed By: jhenderson, grimar, MaskRay
Differential Revision: https://reviews.llvm.org/D82073
This patch enables yaml2elf emit the .debug_abbrev section.
The generated .debug_abbrev is verified using `llvm-dwarfdump`.
Known issues that will be addressed later:
- Current implementation doesn't support generating multiple abbreviation tables in one .debug_abbrev section.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D81820
This patch helps change the return type of `writeVariableSizedInteger()` from `void` to `Error`.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81915
This adds 4 new reloc types.
A lot of code that previously assumed any memory or offset values could be contained in a uint32_t (and often truncated results from functions returning 64-bit values) have been upgraded to uint64_t. This is not comprehensive: it is only the values that come in contact with the new relocation values and their dependents.
A new tablegen mapping was added to automatically upgrade loads/stores in the assembler, which otherwise has no way to select for these instructions (since they are indentical other than for the offset immediate). It follows a similar technique to https://reviews.llvm.org/D53307
Differential Revision: https://reviews.llvm.org/D81704
We have an issue currently. The following YAML piece just ignores the `Excluded` key.
```
SectionHeaderTable:
Sections: []
Excluded:
- Name: .foo
```
Currently the meaning is: exclude the whole table.
The code checks that the `Sections` key is empty and doesn't catch/check
invalid/duplicated/missed `Excluded` entries.
Also there is no way to exclude all sections except the first null section,
because `Sections: []` currently just excludes the whole the sections header table.
To fix it, I suggest a change of the behavior.
1) A new `NoHeaders` key is added. It provides an explicit syntax to drop the whole table.
2) The meaning of the following is changed:
```
SectionHeaderTable:
Sections: []
Excluded:
- Name: .foo
```
Assuming there are 2 sections in the object (a null section and `.foo`), with this patch it
means: exclude the `.foo` section, keep the null section. The null section is an implicit
section and I think it is reasonable to make "Sections: []" to mean it is implicitly added.
It will be consistent with the global "Sections" tag that is used to describe sections.
3) `SectionHeaderTable->Sections` is now optional. No `Sections` is the same as
`Sections: []` (I think it avoids a confusion).
4) Using of `NoHeaders` together with `Sections`/`Excluded` is not allowed.
5) It is possible to use the `Excluded` key without the `Sections` key now (in this case
`Excluded` must contain all sections).
6) `SectionHeaderTable:` or `SectionHeaderTable: []` is not allowed.
7) When the `SectionHeaderTable` key is present, we still require all sections to be
present in `Sections` and `Excluded` lists. No changes here, we are still strict.
Differential revision: https://reviews.llvm.org/D81655
This patch adds a new field `bool Is64bit` in `DWARFYAML::Data` to indicate the address size of target. It's helpful for inferring the `AddrSize` in some DWARF sections.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D81709
This teaches yaml2obj to allocate file space for a no-bits section
when there is a non-nobits section in the same segment that follows it.
It was discussed in D78005 thread and matches GNU linkers and LLD behavior.
Differential revision: https://reviews.llvm.org/D80629
Before this patch, we have to calculate the offset for the current range list entry. This patch helps make the "Offset" field optional.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81220
The `debug_info_offset`(`CuOffset`) should be 64-bit width rather than 32-bit width in DWARF64 .debug_aranges section. This patch helps resolve it.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81528
Multiple times we faced an issue of huge outputs due to unexpected behavior
or incorrect test cases. The last one was https://reviews.llvm.org/D80629#2073066.
This patch limits the output to 10 Mb for ELF and introduces the --max-size to change this
limit.
I've tried to keep the implementation non-intrusive.
The current logic we have is that we prepare section content in a buffer first and write
it to the output later. This patch checks the available limit on each writing attempt to this buffer
and stops writing when the limit is reached and raises the internal error flag.
Later, this flag is is checked before the actual writing to a file happens and
an error is reported.
Differential revision: https://reviews.llvm.org/D81258
This patch enables yaml2elf emit the .debug_line section.
Test cases for emitting the dwarf64 .debug_line section and opcodes will be added later.
Known issues:
- We should replace `InitialLength` with `Format` and `Length`
- Currently implementation of the .debug_line section only fully supports DWARFv2, some header fields in DWARFv4 and DWARFv5 is missing, e.g., `header_length` in DWARFv4, `address_size` and `segment_selector_size` in DWARFv5.
- Some opcodes relies on the .debug_info section, we should warn user about it.
These issues will be addressed in a follow-up patch.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D81450
This patch helps make yaml2obj emit an error message when we try to assign an invalid offset to the entry of the 'debug_ranges' section.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81357
This patch intends to be an NFC-patch. Test cases will be added in a follow-up patch.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D81356
This patch addresses the comment in [D80972](https://reviews.llvm.org/D80972#inline-744217).
Before this patch, the initial length field of .debug_aranges section should be declared as:
```
## 32-bit DWARF
debug_aranges:
- Length:
TotalLength: 0x20
Version: 2
...
## 64-bit DWARF
debug_aranges:
- Length:
TotalLength: 0xffffffff
TotalLength64: 0x20
Version: 2
...
```
After this patch:
```
## 32-bit DWARF
debug_aranges:
- [[Format: DWARF32]] ## Optional
Length: 0x20
Version: 2
...
## 64-bit DWARF
debug_aranges:
- Format: DWARF64
Length: 0x20
Version: 2
```
Current implementation of generating DWARF64 .debug_aranges section is buggy. A follow-up patch will improve it and add test cases for DWARF64.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81063
This implements a new "Excluded" key that can be used
to exclude entries from section header:
```
SectionHeaderTable:
Sections:
...
Excluded:
- Name: .foo
```
Differential revision: https://reviews.llvm.org/D81005
This patch helps infer the endianness of DWARF sections from `FileHeader`.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D81051
This patch enables yaml2obj to emit the .debug_aranges section in ELFYAML.
Known issues:
- The current implementation of `debug_aranges` doesn't support emitting `segment` in the `(segment, address, length)` tuple. I will fix it in a follow-up patch.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D80972
This teaches yaml2obj to allocate file space for a no-bits section
when there is a non-nobits section in the same segment that follows it.
It was discussed in D78005 thread and matches GNU linkers and LLD behavior.
Differential revision: https://reviews.llvm.org/D80629
This patch helps make the `PubSection` optional in the DWARF structure.
Reviewed By: jhenderson, aprantl
Differential Revision: https://reviews.llvm.org/D80722
With the "SectionHeaderTable" it is now possible to reorder
entries in the section header table.
It also allows to stop emitting the table.
Differential revision: https://reviews.llvm.org/D80002
Summary:
Define ELF binary code for VE and modify code where should use this new code.
Depends on D79544.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D79545
Each `ELFYAML::ProgramHeader` currently contains a list of section names
included. We are trying to map them to Fill/Sections very late,
though we can create such mapping early, in `initProgramHeaders`.
The benefit is that with such change it is possible to access mapped
chunks earlier (for example during writing section content) and have
simpler code.
Differential revision: https://reviews.llvm.org/D80520
This change does not affect the produced binary.
In this patch I assign a technical suffix to each section/fill
(i.e. chunk) name when it is empty. It allows to simplify the code
slightly and improve error messages reported.
In the code we have the section to index mapping, SN2I, which is
globally used. With this change we can use it to map "empty"
names to indexes now, what is helpful.
Differential revision: https://reviews.llvm.org/D79984
For describing section/symbol names we can use unique suffixes,
e.g:
```
- Name: '.foo [1]`
- Name: '.foo [2]`
```
It can be a problem (see https://reviews.llvm.org/D79984#inline-734829),
because `[]` are sometimes used to describe a macros:
```
- Name: "[[a0]]"
```
Seems the better approach is to use something else, like "()".
This patch does it and refactors the code related.
Differential revision: https://reviews.llvm.org/D80123
Currently there is no good way to set a physical offset for a section:
* We have the `ShOffset` that allows to override the `sh_offset`, but
it does not affect the real data written.
* We can use a `Filler` to create an artificial gap, but it is more like a hack
rather than a proper solution for this problem.
This patch adds the `Offset` property which allows setting physical
offsets for sections.
It also generalizes the code, so that we set sh_offset field in one place
Differential revision: https://reviews.llvm.org/D78927
Summary: This allows DIEs with DW_AT_ranges to be encoded and decoded _and_ actually have their address ranges be included instead of having DW_AT_ranges with a section offset value for a section that doesn't exist.
Reviewers: labath, aprantl, JDevlieghere, dblaikie, probinson
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D78782
This accounts for a large portion of the memory allocations in LLD.
This DebugSubsectionRecordBuilder object can be stored directly in
C13Builders, it mostly wraps other subsections.
Remove the container kind field from the object. It is always the same
for all elements in the vector, and we can pass it in during writing.
Currently we have computations of `p_filesz` and `p_memsz` mixed together
with the use of a loop over fragments. After recent changes it is possible to
avoid using a loop for the computation of `p_filesz`, since we know that fragments
are sorted by their file offsets.
The main benefit of this change is that splits the computation of `p_filesz`
and `p_memsz` what is simpler and allows us to fix the computation of the
`p_memsz` independently (D78005 shows the issue that we have currently).
Differential revision: https://reviews.llvm.org/D78628
It allows to simplify the current code and also
might help for the code around.
It is also consistent with what we do for another headers,
e.g. section headers, elf file header etc.
Differential revision: https://reviews.llvm.org/D78627
Add support for relocations for MachO to ObjectYAML / yaml2obj / obj2yaml.
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D77844
The `Offset` field is used to set the file offset of a program header.
In a normal object it should not be greater than the minimal offset
of sections included into segment.
This patch adds a check for that and adds tests.
Differential revision: https://reviews.llvm.org/D78304
This validates that sections listed for a segment in the YAML
declaration are ordered by their file offsets.
It might help to simplify the file size computation, but also
is useful by itself as helps to avoid issues in test cases and
to maintain their readability.
Differential revision: https://reviews.llvm.org/D78361
Leverage ARM ELF build attribute section to create ELF attribute section
for RISC-V. Extract the common part of parsing logic for this section
into ELFAttributeParser.[cpp|h] and ELFAttributes.[cpp|h].
Differential Revision: https://reviews.llvm.org/D74023
This patch makes `Relocation::Addend` to be `ELFYAML::YAMLIntUInt` and not `int64_t`.
`ELFYAML::YAMLIntUInt` it is a new type and it has the following benefits/features:
1) For an 64-bit object any hex/decimal addends
in the range [INT64_MIN, UINT64_MAX] is accepted.
2) For an 32-bit object any hex/decimal addends
in range [INT32_MIN, UINT32_MAX] is accepted.
3) Negative hex numbers like -0xffffffff are not accepted.
4) It is printed as decimal. I.e. obj2yaml will print
something like "Addend: 125", this matches the current behavior.
This fixes all FIXMEs in `relocation-addend.yaml`.
Differential revision: https://reviews.llvm.org/D75527
`PAddr` corresponds to `p_paddr` of a program header, which is the segment's physical
address for systems in which physical addressing is relevant. `p_paddr` is often equal
to `p_vaddr`, which is the virtual address of a segment.
This patch changes the default for `PAddr` from 0 to a value of `VAddr`.
Differential revision: https://reviews.llvm.org/D76131
Currently `yaml2obj` require `Offset` field in a relocation description.
There are many cases when `Offset` is insignificant in a context of a test case.
Making `Offset` optional allows to simplify our test cases.
This is what this patch does.
Also, with this patch `obj2yaml` does not dump a zero offset of a relocation.
Differential revision: https://reviews.llvm.org/D75608
I've noticed that it is not convenient to create YAMLs from
binaries (using obj2yaml) that have to be test cases for obj2yaml
later (after applying yaml2obj).
The problem, for example is that obj2yaml emits "DynamicSymbols:"
key instead of .dynsym. It also does not create .dynstr.
And when a YAML document without explicitly defined .dynsym/.dynstr
is given to yaml2obj, we have issues:
1) These sections are placed after non-allocatable sections (I've fixed it in D74756).
2) They have VA == 0. User needs create descriptions for such sections explicitly manually
to set a VA.
This patch addresses (2). I suggest to let yaml2obj assign virtual addresses by itself.
It makes an output binary to be much closer to "normal" ELF.
(It is still possible to use "Address: 0x0" for a section to get the original behavior
if it is needed)
Differential revision: https://reviews.llvm.org/D74764
.dynsym and .dynstr are allocatable and therefore normally are placed
before non-allocatable .strtab, .shstrtab, .symtab sections.
But we are placing them after currently what creates a mix of
alloc/non-alloc sections and does not look normal.
Differential revision: https://reviews.llvm.org/D74756
Previously the description allowed to describe symbols with use of
`Name` and `Index` keys. This patch removes them and now it is still
possible to use either names or symbol indexes, but the code is simpler
and the format is slightly different.
Such a change will be useful for another patches, e.g:
https://reviews.llvm.org/D73788#inline-671077
Differential revision: https://reviews.llvm.org/D73888
We are missing ability to override the sh_entsize field for
SHT_REL[A] sections. It would be useful for writing test cases.
Differential revision: https://reviews.llvm.org/D73621
Note: this is a reland with a trivial 2 lines fix in ELFState<ELFT>::writeSectionContent.
It adds a check similar to ones we already have for other sections to fix the case revealed
by bots, like http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/60744.
The encoded sequence of Elf*_Relr entries in a SHT_RELR section looks
like [ AAAAAAAA BBBBBBB1 BBBBBBB1 ... AAAAAAAA BBBBBB1 ... ]
i.e. start with an address, followed by any number of bitmaps. The address
entry encodes 1 relocation. The subsequent bitmap entries encode up to 63(31)
relocations each, at subsequent offsets following the last address entry.
More information is here:
https://github.com/llvm-mirror/llvm/blob/master/lib/Object/ELF.cpp#L272
This patch adds a support for these sections.
Differential revision: https://reviews.llvm.org/D71872
The encoded sequence of Elf*_Relr entries in a SHT_RELR section looks
like [ AAAAAAAA BBBBBBB1 BBBBBBB1 ... AAAAAAAA BBBBBB1 ... ]
i.e. start with an address, followed by any number of bitmaps. The address
entry encodes 1 relocation. The subsequent bitmap entries encode up to 63(31)
relocations each, at subsequent offsets following the last address entry.
More information is here:
https://github.com/llvm-mirror/llvm/blob/master/lib/Object/ELF.cpp#L272
This patch adds a support for these sections.
Differential revision: https://reviews.llvm.org/D71872
There was no way to set an unsupported or unknown OS ABI.
With this patch it is possible to use any numeric value.
Differential revision: https://reviews.llvm.org/D71765
Currently we have the `Flags` property that allows to
set flags for a section. The problem is that it does not
allow us to set an arbitrary value, because of bit fields
validation under the hood. An arbitrary values can be used
to test specific broken cases.
We probably do not want to relax the validation, so this
patch adds a `ShSize` property that allows to
override the `sh_size`. It is inline with others `Sh*` properties
we have already.
Differential revision: https://reviews.llvm.org/D71411
The PT_GNU_PROPERTY is generated by a linker to describe the
.note.gnu.property section. The Linux kernel uses this program header to
locate the .note.gnu.property section.
It is described in "The Linux gABI extension"
Include support for llvm-readelf, llvm-readobj and the yaml reader and
writers.
Differential Revision: https://reviews.llvm.org/D70959
We already have Symbols property to list regular symbols and
it is currently Optional<>. This patch makes DynamicSymbols to be optional
too. With this there is no need to define a dummy symbol anymore to trigger
creation of the .dynsym and it is now possible to define an empty .dynsym using
just the following line:
DynamicSymbols: []
(it is important to have when you do not want to have dynamic symbols,
but want to have a .dynsym)
Now the code is consistent and it helped to fix a bug: previously we
did not report an error when both Content/Size and an empty
Symbols/DynamicSymbols list were specified.
Differential revision: https://reviews.llvm.org/D70956
This section contains strings specifying libraries to be added to the link by the linker.
The strings are encoded as standard null-terminated UTF-8 strings.
This patch adds a way to describe and dump SHT_LLVM_DEPENDENT_LIBRARIES sections.
I introduced a new YAMLFlowString type here. That used to teach obj2yaml to dump
them like:
```
Libraries: [ foo, bar ]
```
instead of the following (if StringRef would be used):
```
Libraries:
- foo
- bar
```
Differential revision: https://reviews.llvm.org/D70598
Summary:
Most libraries are defined in the lib/ directory but there are also a
few libraries defined in tools/ e.g. libLLVM, libLTO. I'm defining
"Component Libraries" as libraries defined in lib/ that may be included in
libLLVM.so. Explicitly marking the libraries in lib/ as component
libraries allows us to remove some fragile checks that attempt to
differentiate between lib/ libraries and tools/ libraires:
1. In tools/llvm-shlib, because
llvm_map_components_to_libnames(LIB_NAMES "all") returned a list of
all libraries defined in the whole project, there was custom code
needed to filter out libraries defined in tools/, none of which should
be included in libLLVM.so. This code assumed that any library
defined as static was from lib/ and everything else should be
excluded.
With this change, llvm_map_components_to_libnames(LIB_NAMES, "all")
only returns libraries that have been added to the LLVM_COMPONENT_LIBS
global cmake property, so this custom filtering logic can be removed.
Doing this also fixes the build with BUILD_SHARED_LIBS=ON
and LLVM_BUILD_LLVM_DYLIB=ON.
2. There was some code in llvm_add_library that assumed that
libraries defined in lib/ would not have LLVM_LINK_COMPONENTS or
ARG_LINK_COMPONENTS set. This is only true because libraries
defined lib lib/ use LLVMBuild.txt and don't set these values.
This code has been fixed now to check if the library has been
explicitly marked as a component library, which should now make it
easier to remove LLVMBuild at some point in the future.
I have tested this patch on Windows, MacOS and Linux with release builds
and the following combinations of CMake options:
- "" (No options)
- -DLLVM_BUILD_LLVM_DYLIB=ON
- -DLLVM_LINK_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_BUILD_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_LINK_LLVM_DYLIB=ON
Reviewers: beanz, smeenai, compnerd, phosek
Reviewed By: beanz
Subscribers: wuzish, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, mgorny, mehdi_amini, sbc100, jgravelle-google, hiraditya, aheejin, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, dang, Jim, lenary, s.egerton, pzheng, sameer.abuasal, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70179
This recommits 089c0f5814, which was
reverted due to failing tests on big endian machines. It includes a fix
which I believe (I don't have BE machine) should fix this issue. The fix
consists of correcting the invocation DWARFYAML::EmitDebugSections,
which was missing one (default) function arguments, and so didn't
actually force the little-endian mode.
The original commit message follows.
Summary:
This patch adds DWARFDie::getLocations, which returns the location
expressions for a given attribute (typically DW_AT_location). It handles
both "inline" locations and references to the external location list
sections (currently only of the DW_FORM_sec_offset type). It is
implemented on top of DWARFUnit::findLoclistFromOffset, which is also
added in this patch. I tried to make their signatures similar to the
equivalent range list functionality.
The actual location list interpretation logic is in
DWARFLocationTable::visitAbsoluteLocationList. This part is not
equivalent to the range list code, but this deviation is motivated by a
desire to reuse the same location list parsing code within lldb.
The functionality is tested via a c++ unit test of the DWARFDie API.
Reviewers: dblaikie, JDevlieghere, SouraVX
Subscribers: mgorny, hiraditya, cmtice, probinson, llvm-commits, aprantl
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70394
Summary:
This patch adds DWARFDie::getLocations, which returns the location
expressions for a given attribute (typically DW_AT_location). It handles
both "inline" locations and references to the external location list
sections (currently only of the DW_FORM_sec_offset type). It is
implemented on top of DWARFUnit::findLoclistFromOffset, which is also
added in this patch. I tried to make their signatures similar to the
equivalent range list functionality.
The actual location list interpretation logic is in
DWARFLocationTable::visitAbsoluteLocationList. This part is not
equivalent to the range list code, but this deviation is motivated by a
desire to reuse the same location list parsing code within lldb.
The functionality is tested via a c++ unit test of the DWARFDie API.
Reviewers: dblaikie, JDevlieghere, SouraVX
Subscribers: mgorny, hiraditya, cmtice, probinson, llvm-commits, aprantl
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70394
Summary:
The tool does not correctly handle COFF sections with extended relocation tables (with IMAGE_SCN_LNK_NRELOC_OVFL bit set), this patch fixes this problem.
But I have cheated a bit in the test (to make it smaller) because extended relocation table is supposed to be used when the number of relocations exceeds 65534. Otherwise the test size would be pretty big.
Reviewers: jhenderson, MaskRay, mstorsjo
Reviewed By: mstorsjo
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70251
SHT_LLVM_LINKER_OPTIONS section contains pairs of null-terminated strings.
This patch adds support for them.
Differential revision: https://reviews.llvm.org/D69895
Currently there is no way to describe the data that is not a part of an output section.
It can be a data used to align sections or to fill the gaps with something,
or another kind of custom data. In this patch I suggest a way to describe it. It looks like that:
```
Sections:
- Type: CustomFiller
Pattern: "CCDD"
Size: 4
- Name: .bar
Type: SHT_PROGBITS
Content: "FF"
```
I.e. I've added a kind of synthetic section with a synthetic type "CustomFiller".
In the code it is called a "SyntheticFiller", which is "a synthetic section which
might be used to write the custom data around regular output sections. It does
not present in the sections header table, but it might affect the output file size and
program headers produced. Think about it as about piece of data."
`SyntheticFiller` currently has a `Pattern` field and a `Size` field + an optional `Name`.
When written, `Size` of bytes in the output will be filled with a `Pattern`.
It is possible to reference a named filler it by name from the program headers description,
just like any other normal section.
Differential revision: https://reviews.llvm.org/D69709
Summary:
Rewrite one of the invalid macho test input file with YAML file. The
original invalid macho is breaking our internal test infrastusture
because it is too broken to be copy around.
Need to relax an assertion in the YAML/MachoEmitter to allow yaml2obj to
write an invalid object like this.
rdar://problem/56879982
Reviewers: beanz, mtrent
Reviewed By: beanz
Subscribers: hiraditya, jkorous, dexonsmith, ributzka, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69856
This is the "official" constant for arm64. We also have another constant
for arm64 (called BP_ARM64), which was used by breakpad while there was
no official constant for arm64 available.
The architecture enum contains two kinds of contstants: the "official" ones
defined by Microsoft, and unofficial constants added by breakpad to cover the
architectures not described by the first ones.
Up until now, there was no big need to differentiate between the two. However,
now that Microsoft has defined
https://docs.microsoft.com/en-us/windows/win32/api/sysinfoapi/ns-sysinfoapi-system_info
a constant for ARM64, we have a name clash.
This patch renames all breakpad-defined constants with to include the prefix
"BP_". This frees up the name "ARM64", which I'll re-introduce with the new
"official" value in a follow-up patch.
Reviewers: amccarth, clayborg
Subscribers: lldb-commits, llvm-commits
Differential Revision: https://reviews.llvm.org/D69285
Before this change .symtab section was required for SHT_REL[A] section
declarations. yaml2obj automatically defined it in case when YAML document
did not have it.
With this change it is now possible to produce an object that
has a relocation section, but has no symbol table.
It simplifies the code and also it is inline with how we handle Link fields
for another special sections.
Differential revision: https://reviews.llvm.org/D69260
Currently, when we do not specify "Info" field in a YAML description
for SHT_GROUP section, yaml2obj reports an error:
"error: unknown symbol referenced: '' by YAML section '.group1'"
Also, we do not link it with a symbol table by default,
though it is what we do for AddrsigSection, HashSection, RelocationSection.
(http://www.sco.com/developers/gabi/latest/ch4.sheader.html#sh_link)
The patch fixes missings mentioned.
Differential revision: https://reviews.llvm.org/D69299
SHT_NOTE is the section that consists of
namesz, descsz, type, name + padding, desc + padding data.
This patch teaches yaml2obj, obj2yaml to dump and parse them.
This patch implements the section how it is described here:
https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-18048.html
Which says: "For 64–bit objects and 32–bit objects, each entry is an array of 4-byte words in
the format of the target processor"
The official specification is different
http://www.sco.com/developers/gabi/latest/ch5.pheader.html#note_section
And says: "n 64-bit objects (files with e_ident[EI_CLASS] equal to ELFCLASS64), each entry is an array
of 8-byte words in the format of the target processor. In 32-bit objects (files with e_ident[EI_CLASS]
equal to ELFCLASS32), each entry is an array of 4-byte words in the format of the target processor"
Since LLVM uses the first, 32-bit way, this patch follows it.
Differential revision: https://reviews.llvm.org/D68983
This patch tries to resolve problems faced in D68943
and uses some of the code written by Konrad Wilhelm Kleine
in that patch.
Previously, yaml2obj tool always created a .symtab section.
This patch changes that. With it we only create it when
have a "Symbols:" tag in the YAML document or when
we need to create it because it is used by another section(s).
obj2yaml follows the new behavior and does not print "Symbols:"
anymore when there is no symbol table.
Differential revision: https://reviews.llvm.org/D69041
llvm-svn: 375361
Summary:
Also changes the wasm YAML format to reflect the possibility of having
multiple return types and to put the returns after the params for
consistency with the binary encoding.
Reviewers: aheejin, sbc100
Subscribers: dschuff, jgravelle-google, hiraditya, sunfish, arphaman, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69156
llvm-svn: 375283
Summary:
The implementation is fairly straight-forward and uses the same patterns
as the existing streams. The yaml form does not attempt to preserve the
data in the "gaps" that can be created by setting a larger-than-required
header or entry size in the stream header, because the existing consumer
(lldb) does not make use of the information in the gap in any way, and
attempting to preserve that would make the implementation more
complicated.
Reviewers: amccarth, jhenderson, clayborg
Subscribers: llvm-commits, lldb-commits, markmentovai, zturner, JosephTremoulet
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68645
llvm-svn: 374337
It allows using "Size" with or without "Content" in YAML descriptions of
SHT_LLVM_ADDRSIG sections.
Differential revision: https://reviews.llvm.org/D68334
llvm-svn: 373610
This is a follow-up for D68085 which allows using "Size"
tag together with "Content" tag or alone.
Differential revision: https://reviews.llvm.org/D68216
llvm-svn: 373473
Currently we can't use unique suffixes in section names to describe
stack sizes sections. E.g. '.stack_sizes [1]' will be treated as a regular section.
This happens because we recognize stack sizes section by name and
do not yet drop the suffix before the check.
The patch fixes it.
Differential revision: https://reviews.llvm.org/D68018
llvm-svn: 372853
It is a follow-up requested in the review comment
for D67757. Allows to use Content + Size or just Size
when describing .stack_sizes sections in YAML document
Differential revision: https://reviews.llvm.org/D67958
llvm-svn: 372845
.stack_sizes is a SHT_PROGBITS section that contains pairs of
<address (4/8 bytes), stack size (uleb128)>.
This patch teach tools to parse and dump it.
Differential revision: https://reviews.llvm.org/D67757
llvm-svn: 372762
Currently when e_machine is set to something that is not supported by YAML lib,
then tools fail with llvm_unreachable.
In this patch I allow them to handle relocations in this case.
It can be used to dump and create objects for broken or unsupported targets.
Differential revision: https://reviews.llvm.org/D67657
llvm-svn: 372377
We do not support them and fail with llvm_unreachable currently.
This is not the only target we do not support and also seems we are missing
the tests for those we have already. But I needed this one for another patch,
so posted it separatelly.
Relocation names are taken from llvm\include\llvm\BinaryFormat\ELFRelocs\PowerPC64.def
Differential revision: https://reviews.llvm.org/D67615
llvm-svn: 372109
Currently we only allow using a known named constants
for `Machine` field in YAML documents.
This patch allows using any numbers (valid or "unknown")
and adds test cases for current and new functionality.
With this it is possible to write a test cases for really unknown
EM_* targets.
Differential revision: https://reviews.llvm.org/D67652
llvm-svn: 372108
This is a continuation of the YAML library error reporting
refactoring/improvement and the idea by itself was mentioned
in the following thread:
https://reviews.llvm.org/D67182?id=218714#inline-603404
This performs a cleanup of all object emitters in the library.
It allows using the custom one provided by the caller.
One of the nice things is that each tool can now print its tool name,
e.g: "yaml2obj: error: <text>"
Also, the code became a bit simpler.
Differential revision: https://reviews.llvm.org/D67445
llvm-svn: 371865
The address difference between two sections in a PT_LOAD is a constant.
Consider a hypothetical case (pagesize can be very small, say, 4).
```
.text sh_addralign=4
.text.hot sh_addralign=16
```
If we set p_align to 4, the PT_LOAD will be loaded at an address which
is a multiple of 4. The address of .text.hot is guaranteed to be a
multiple of 4, but not necessarily a multiple of 16.
This patch deletes the constraint
if (SHeader->sh_offset == PHeader.p_offset)
Reviewed By: grimar, jhenderson
Differential Revision: https://reviews.llvm.org/D67260
llvm-svn: 371501
This fixes a bug as well. When "FileSize:" (p_filesz) is specified and
different from the actual value, the following code probably should not
use PHeader.p_filesz:
if (SHeader->sh_offset == PHeader.p_offset + PHeader.p_filesz)
PHeader.p_memsz += SHeader->sh_size;
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D67256
llvm-svn: 371420
The aim of this patch is to refactor how we handle and report error.
I suggest to use the same approach we use in LLD: delayed error reporting.
For that I introduced 'HasError' flag which triggers when we report an error.
Now we do not exit instantly on any error. The benefits are:
1) There are no more 'exit(1)' calls in the library code.
2) Code was simplified significantly in a few places.
3) It is now possible to print multiple errors instead of only one.
Also, I changed the messages to be lower case and removed a full stop.
Differential revision: https://reviews.llvm.org/D67182
llvm-svn: 371380
`struct Elf*_Shdr` has a field `sh_offset`, named `ShOffset` in
llvm::ELFYAML::Section. Rename SHOffset (e_shoff) to SHOff to prevent confusion.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67254
llvm-svn: 371185
Summary: It says [[ http://www.sco.com/developers/gabi/latest/ch4.eheader.html | here ]] that if there are no program headers than e_phoff should be 0, but currently it is always set after the header. GNU's `readelf` (but not `llvm-readelf`) complains about this: `readelf: Warning: possibly corrupt ELF header - it has a non-zero program header offset, but no program headers`.
Reviewers: jhenderson, grimar, MaskRay, rupprecht
Reviewed By: jhenderson, grimar, MaskRay
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67054
llvm-svn: 371162
See http://lists.llvm.org/pipermail/llvm-dev/2019-February/130583.html
and D60242 for the lld partition feature.
This patch:
* Teaches yaml2obj to parse the 3 section types.
* Teaches llvm-readobj/llvm-readelf to dump the 3 section types.
There is no test for SHT_LLVM_DEPENDENT_LIBRARIES in llvm-readobj. Add
it as well.
Reviewed By: thakis
Differential Revision: https://reviews.llvm.org/D67228
llvm-svn: 371157
Linkers (ld.bfd/gold/lld) place the section header table at the very
end. This allows tools to strip it, which is optional in executable/shared objects.
In addition, if we add or section, the size of the section header table
will change. Placing the section header table in the end keeps section
offsets unchanged.
yaml2obj currently places the section header table immediately after the
program header. Follow what linkers do to make offset updating easier.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67221
llvm-svn: 371074
In D62809 I accidentally added "ELFState<ELFT> &State" as the
first parameter to two methods. There is no reason for having that.
I removed this argument and also moved finalizeStrings declaration to
remove an excessive 'private:' tag.
Differential revision: https://reviews.llvm.org/D67157
llvm-svn: 371033
Fix: added missing return "return 0;"
Original commit message:
This eliminates one of the error(1) call in this lib.
It is different from the others because happens on a fields mapping stage
and can be easily fixed.
Differential revision: https://reviews.llvm.org/D67150
llvm-svn: 371030
This eliminates one of the error(1) call in this lib.
It is different from the others because happens on a fields mapping stage
and can be easily fixed.
Differential revision: https://reviews.llvm.org/D67150
llvm-svn: 371023
PT_GNU_STACK is used in an llvm-objcopy test.
I plan to use PT_GNU_RELRO in a patch to improve nested segment
processing in llvm-objcopy (PR42963).
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67146
llvm-svn: 370857
This is in line with the previous changes which allowed to
override the sh_offset/sh_size and useful for writing test cases.
Differential revision: https://reviews.llvm.org/D66998
llvm-svn: 370633
Currenly we can encode the 'st_other' field of symbol using 3 fields.
'Visibility' is used to encode STV_* values.
'Other' is used to encode everything except the visibility, but it can't handle arbitrary values.
'StOther' is used to encode arbitrary values when 'Visibility'/'Other' are not helpfull enough.
'st_other' field is used to encode symbol visibility and platform-dependent
flags and values. Problem to encode it is that it consists of Visibility part (STV_* values)
which are enumeration values and the Other part, which is different and inconsistent.
For MIPS the Other part contains flags for all STO_MIPS_* values except STO_MIPS_MIPS16.
(Like comment in ELFDumper says: "Someones in their infinite wisdom decided to make
STO_MIPS_MIPS16 flag overlapped with other ST_MIPS_xxx flags."...)
And for PPC64 the Other part might actually encode any value.
This patch implements custom logic for handling the st_other and removes
'Visibility' and 'StOther' fields.
Here is an example of a new YAML style this patch allows:
- Name: foo
Other: [ 0x4 ]
- Name: bar
Other: [ STV_PROTECTED, 4 ]
- Name: zed
Other: [ STV_PROTECTED, STO_MIPS_OPTIONAL, 0xf8 ]
Differential revision: https://reviews.llvm.org/D66886
llvm-svn: 370472
Add an WASM_SYMBOL_NO_STRIP flag, so that __attribute__((used)) doesn't
need to imply exporting. When targeting Emscripten, have
WASM_SYMBOL_NO_STRIP imply exporting.
Differential Revision: https://reviews.llvm.org/D62542
llvm-svn: 370415
This allows us to produce broken binaries with local
symbols placed after global in '.dynsym'/'.symtab'
Also, simplifies the code.
Differential revision: https://reviews.llvm.org/D66799
llvm-svn: 370331
This relands this commit, I mistakenly reverted the original change
thinking it was the cause of the observed MSan failures but it was not.
llvm-svn: 370206
This is a follow up discussed in the comments of D66583.
Currently, if for example, we have both StOther and Other set in YAML document for a symbol,
then yaml2obj reports an "unknown key 'Other'" error.
It happens because 'mapOptional()' is never called for 'Other/Visibility' in this case,
leaving those unhandled.
This message does not describe the reason of the error well. This patch fixes it.
Differential revision: https://reviews.llvm.org/D66642
llvm-svn: 370032
st_other field of a symbol usually contains its visibility.
Other bits are usually 0, though some targets, like
MIPS can set them using the named bit field values.
Problem is that there is no way to set an arbitrary value now,
though that might be useful for our test cases.
In this patch I introduced a way to set st_other to any numeric
value using the new StOther field.
I added a test and simplified the existent one to show the effect/benefit
Differential revision: https://reviews.llvm.org/D66583
llvm-svn: 369742
This fixes https://bugs.llvm.org/show_bug.cgi?id=40337.
Previously, it was always assumed that relocations referenced symbols in the static symbol table.
Now, if the Link field references a section called ".dynsym" it will look up these symbols
in the dynamic symbol table.
This patch is heavily based on D59097 by James Henderson
Differential revision: https://reviews.llvm.org/D66532
llvm-svn: 369645
Summary:
The code for serializing minidumps was living in MinidumpYAML.cpp
so that it would be accessible from unit tests. While this had its
advantages, it was also unfortunate because it broke symmetry with all
other yaml2obj serializers.
Fortunately, nowadays all of yaml2obj is a library, so we don't need to
do anything special. This patch improves the code consistency by moving
the serialization code to MinidumpEmitter.cpp to match the style used in
other backends. It also removes the writeAsBinary entry point in favor
of the more general convertYAML interface.
This patch is just massaging the code a bit. There shouldn't be any
functional change here.
Reviewers: jhenderson, abrachet
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66474
llvm-svn: 369517
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
llvm-svn: 369013
In some cases a symbol might have section index == SHN_XINDEX.
This is an escape value indicating that the actual section header index
is too large to fit in the containing field.
Then the SHT_SYMTAB_SHNDX section is used. It contains the 32bit values
that stores section indexes.
ELF gABI says that there can be multiple SHT_SYMTAB_SHNDX sections,
i.e. for example one for .symtab and one for .dynsym
(1) https://groups.google.com/forum/#!topic/generic-abi/-XJAV5d8PRg
(2) DT_SYMTAB_SHNDX: http://www.sco.com/developers/gabi/latest/ch5.dynamic.html
In this patch I am only supporting a single SHT_SYMTAB_SHNDX associated
with a .symtab. This is a more or less common case which is used a few tests I saw in LLVM.
I decided not to create the SHT_SYMTAB_SHNDX section as "implicit",
but implement is like a kind of regular section for now.
i.e. tools do not recreate this section or its content, like they do for
symbol table sections, for example. That should allow to write all kind of
possible broken test cases for our needs and keep the output closer to requested.
Differential revision: https://reviews.llvm.org/D65446
llvm-svn: 368272
There is no way to set broken sh_size field currently
for sections. It can be usefull for writing the
test cases.
Differential revision: https://reviews.llvm.org/D64401
llvm-svn: 365766
Some of our test cases are using objects which
has sections with a broken sh_offset field.
There was no way to set it from YAML until this patch.
Differential revision: https://reviews.llvm.org/D63879
llvm-svn: 364898
This allows setting different values for e_shentsize, e_shoff, e_shnum
and e_shstrndx fields and is useful for producing broken inputs for various
test cases.
Differential revision: https://reviews.llvm.org/D63771
llvm-svn: 364517
Summary:
The directive defines a symbol as an group/local memory (LDS) symbol.
LDS symbols behave similar to common symbols for the purposes of ELF,
using the processor-specific SHN_AMDGPU_LDS as section index.
It is the linker and/or runtime loader's job to "instantiate" LDS symbols
and resolve relocations that reference them.
It is not possible to initialize LDS memory (not even zero-initialize
as for .bss).
We want to be able to link together objects -- starting with relocatable
objects, but possible expanding to shared objects in the future -- that
access LDS memory in a flexible way.
LDS memory is in an address space that is entirely separate from the
address space that contains the program image (code and normal data),
so having program segments for it doesn't really make sense.
Furthermore, we want to be able to compile multiple kernels in a
compilation unit which have disjoint use of LDS memory. In that case,
we may want to place LDS symbols differently for different kernels
to save memory (LDS memory is very limited and physically private to
each kernel invocation), so we can't simply place LDS symbols in a
.lds section.
Hence this solution where LDS symbols always stay undefined.
Change-Id: I08cbc37a7c0c32f53f7b6123aa0afc91dbc1748f
Reviewers: arsenm, rampitec, t-tye, b-sumner, jsjodin
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, rupprecht, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61493
llvm-svn: 364296
With this patch we get ability to set any flags we want
for implicit sections defined in YAML.
Differential revision: https://reviews.llvm.org/D63136
llvm-svn: 363367
This is a follow-up for D62809.
Content and Size fields should be optional as was discussed in comments
of the D62809's thread. With that, we can describe a specific string table and
symbol table sections in a more correct way and also show appropriate errors.
The patch adds lots of test cases where the behavior is described in details.
Differential revision: https://reviews.llvm.org/D62957
llvm-svn: 362931
In glibc, DT_PPC_GOT indicates that PowerPC32 Secure PLT ABI is used.
I plan to use it in D62464.
DT_PPC_OPT currently indicates if a TLSDESC inspired TLS optimization is
enabled.
Reviewed By: grimar, jhenderson, rupprecht
Differential Revision: https://reviews.llvm.org/D62851
llvm-svn: 362569
Xing GUO