This is the major rename patch that prior patches have built towards.
The DPValue class is being renamed to DbgVariableRecord, which reflects
the updated terminology for the "final" implementation of the RemoveDI
feature. This is a pure string substitution + clang-format patch. The
only manual component of this patch was determining where to perform
these string substitutions: `DPValue` and `DPV` are almost exclusively
used for DbgRecords, *except* for:
- llvm/lib/target, where 'DP' is used to mean double-precision, and so
appears as part of .td files and in variable names. NB: There is a
single existing use of `DPValue` here that refers to debug info, which
I've manually updated.
- llvm/tools/gold, where 'LDPV' is used as a prefix for symbol
visibility enums.
Outside of these places, I've applied several basic string
substitutions, with the intent that they only affect DbgRecord-related
identifiers; I've checked them as I went through to verify this, with
reasonable confidence that there are no unintended changes that slipped
through the cracks. The substitutions applied are all case-sensitive,
and are applied in the order shown:
```
DPValue -> DbgVariableRecord
DPVal -> DbgVarRec
DPV -> DVR
```
Following the previous rename patches, it should be the case that there
are no instances of any of these strings that are meant to refer to the
general case of DbgRecords, or anything other than the DPValue class.
The idea behind this patch is therefore that pure string substitution is
correct in all cases as long as these assumptions hold.
Ensure that when a constant value dies, all ValueAsMetadata uses of that
constant in a DebugValueUser will be replaced with a PoisonValue instead
of a nullptr. This has little visible effect currently, as any nullptr metadata
uses in a DebugValueUser would be converted to an empty MDNode in
the end anyway, but this patch adds an assert that would be triggered by
two existing tests without the functional component of this patch:
llvm/test/Transforms/Inline/delete-function-with-metadata-use.ll
llvm/test/DebugInfo/X86/array2.ll
Add an `-allow-incomplete-ir` flag to the IR parser, which allows
reading IR with missing declarations. This is intended to produce a
best-effort interpretation of the IR, along the same lines of what we
would manually do when taking, for example, a function from
`-print-after-all` output and fixing it up to be valid IR.
This patch only supports dropping references to undeclared metadata,
either by dropping metadata attachments from instructions/functions, or
by dropping calls to certain intrinsics (like debug intrinsics). I will
implement support for inserting missing function/global declarations in
a followup patch.
We don't have real use lists for metadata, so the approach here is to
iterate over the whole IR and identify metadata that needs to be
dropped. This does not support all possible cases, but should handle
anything that's relevant for the function-only IR use case.
`ValueAsMetadata::handleRAUW` is a mechanism to replace all metadata
referring to one value by a different value.
Relax an assert that used to enforce the old and new value to have the
same type.
This seems to be a sanity plausibility assert only, as the
implementation actually supports mismatching types.
This is motivated by a downstream mechanism where we use poison
ValueAsMetadata values to annotate pointee types of opaque pointer
function arguments.
When replacing one type with a different one to work around DXIL vs LLVM
incompatibilities, we need to update type annotations, and handleRAUW is
more efficient than creating new MD nodes.
This patch is a necessary step to allowing the new non-intrinsic debug
info to replace llvm.dbg.assign intrinsics. DIAssignIDs must be able to
look up the debug assigns that refer to them, and this patch makes them
always be considered "replaceable", allowing us to track and replace uses
for non-temporary instances.
This is a small patch attempting to fix an error with a prior patch which
caused buildbot failures on certain targets; for example:
https://lab.llvm.org/buildbot/#/builders/127/builds/60931
The compile error comes from std::distance not having an overload for a
std::array iterator and a raw pointer; this patch converts the iterator
to a pointer to resolve this.
Fixes d499df02
This implements the DbgAssignIntrinsic class as a variant of DPValues -
unfortunately this involves increasing the size of the `DebugValueUser`
storage by 3x, but this is necessary to enable assigns to be
represented, and can be offset in a future patch by splitting DPValue
into subclasses such that each variant can store only the fields it
needs. This patch does not actually create DPVAssigns in any case;
future patches will handle this variant in all cases where generic
DPValue handling does not. This patch also does not implement tracking
support for DIAssignIDs, which is necessary to find DPVAssigns that
reference a given DIAssignID; that is added in a subsequent patch.
The order of dbg.value intrinsics appearing in the output can affect the
order of tables in DWARF sections. This means that DPValues, our
dbg.value replacement, needs to obey the same ordering rules. For
dbg.values returned by findDbgUsers it's reverse order of creation (due
to how they're put on use-lists). Produce that order from findDbgUsers
for DPValues.
I've got a few IR files where the order of dbg.values flips, but it's a
fragile test -- ultimately it needs the number of times a DPValue is
handled by findDbgValues to be odd.
This reverts commit 0fd5dc94380d5fe666dc6c603b4bb782cef743e7.
The original commit removed DIArgLists from being in an MDNode map, but did
not insert a new `delete` in the LLVMContextImpl destructor. This
reapply adds that call to delete, preventing a memory leak.
This patch changes the `DIArgList` class's inheritance from `MDNode` to
`Metadata, ReplaceableMetadataImpl`, and ensures that it is always
unique, i.e. a distinct DIArgList should never be produced.
This should not result in any changes to IR or bitcode parsing and
printing, as the format for DIArgList is unchanged, and the order in which it
appears should also be identical. As a minor note, this patch also fixes
a gap in the verifier, where the ValueAsMetadata operands to a DIArgList
would not be visited.
This reverts commit 957efa4ce4f0391147cec62746e997226ee2b836.
Original commit message below -- in this follow up, I've shifted
un-necessary inclusions of DebugProgramInstruction.h into being forward
declarations (fixes clang-compile time I hope), and a memory leak in the
DebugInfoTest.cpp IR unittests.
I also tracked a compile-time regression in D154080, more explanation
there, but the result of which is hiding some of the changes behind the
EXPERIMENTAL_DEBUGINFO_ITERATORS compile-time flag. This is tested by the
"new-debug-iterators" buildbot.
[DebugInfo][RemoveDIs] Add prototype storage classes for "new" debug-info
This patch adds a variety of classes needed to record variable location
debug-info without using the existing intrinsic approach, see the rationale
at [0].
The two added files and corresponding unit tests are the majority of the
plumbing required for this, but at this point isn't accessible from the
rest of LLVM as we need to stage it into the repo gently. An overview is
that classes are added for recording variable information attached to Real
(TM) instructions, in the form of DPValues and DPMarker objects. The
metadata-uses of DPValues is plumbed into the metadata hierachy, and a
field added to class Instruction, which are all stimulated in the unit
tests. The next few patches in this series add utilities to convert to/from
this new debug-info format and add instruction/block utilities to have
debug-info automatically updated in the background when various operations
occur.
This patch was reviewed in Phab in D153990 and D154080, I've squashed them
together into this commit as there are dependencies between the two
patches, and there's little profit in landing them separately.
[0] https://discourse.llvm.org/t/rfc-instruction-api-changes-needed-to-eliminate-debug-intrinsics-from-ir/68939
And some intervening fixups. There are two remaining problems:
* A memory leak via https://lab.llvm.org/buildbot/#/builders/236/builds/7120/steps/10/logs/stdio
* A performance slowdown with -g where I'm not completely sure what the cause it
These might be fairly straightforwards to fix, but it's the end of the day
hear, so I figure I'll clear the buildbots til tomorrow.
This reverts commit 7d77bbef4ad9230f6f427649373fe46a668aa909.
This reverts commit 9026f35afe6ffdc5e55b6615efcbd36f25b11558.
This reverts commit d97b2b389a0e511c65af6845119eb08b8a2cb473.
This patch adds a variety of classes needed to record variable location
debug-info without using the existing intrinsic approach, see the rationale
at [0].
The two added files and corresponding unit tests are the majority of the
plumbing required for this, but at this point isn't accessible from the
rest of LLVM as we need to stage it into the repo gently. An overview is
that classes are added for recording variable information attached to Real
(TM) instructions, in the form of DPValues and DPMarker objects. The
metadata-uses of DPValues is plumbed into the metadata hierachy, and a
field added to class Instruction, which are all stimulated in the unit
tests. The next few patches in this series add utilities to convert to/from
this new debug-info format and add instruction/block utilities to have
debug-info automatically updated in the background when various operations
occur.
This patch was reviewed in Phab in D153990 and D154080, I've squashed them
together into this commit as there are dependencies between the two
patches, and there's little profit in landing them separately.
[0] https://discourse.llvm.org/t/rfc-instruction-api-changes-needed-to-eliminate-debug-intrinsics-from-ir/68939
Optimize metadata query code:
- Avoid `DenseMap::operator[]` in situations where it is known that the
key exists in the map. Instead use `DenseMap::at()`/
`DenseMap::find()->second`. This avoids code-bloat and bad inlining
decisions for the unused insertion/growing code in `operator[]`.
- Avoid a redundant `Value::hasMetadata()` check.
- Move the `KindID == LLVMContext::MD_dbg` case to
`Instruction::getMetadata` and check it first assuming that it can be
constant folded after inlining in many situations.
The motivation for this change is a regression triggered by
e3cf80c5c1fe55efd8216575ccadea0ab087e79c which could attributed to the
compiler inlining the insertion part of `DenseMap::operator[]` in more
cases while unbeknownst to a compiler (without PGO) that code is never
used in this context. This change improves performance and eliminates
difference before and after that change in my measurements.
Currently if the MD_Annotation node containd a string node when we add a
string tuple node the string will not be preserved. This change fixes
that issue.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D152448
This patch adds a new method setNoSanitizeMetadata() for Instruction, and use it in SanitizerMetadata and SanitizerCoverage.
Reviewed By: nickdesaulniers, MaskRay
Differential Revision: https://reviews.llvm.org/D150632
Annotation metadata supports adding singular annotation strings to annotation block. This patch adds the ability to insert a tuple of strings into the metadata array.
The idea here is that each tuple of strings represents a piece of information that can be all related. It makes it easier to parse through related metadata information given it will be contained in one tuple.
For example in remarks any pass that implements annotation remarks can have different type of remarks and pass additional information for each.
The original behaviour of annotation remarks is preserved here and we can mix tuple annotations and single annotations for the same instruction.
Reviewed By: paquette
Differential Revision: https://reviews.llvm.org/D148328
This patch replaces the uses of PointerUnion.is function by llvm::isa,
PointerUnion.get function by llvm::cast, and PointerUnion.dyn_cast by
llvm::dyn_cast_if_present. This is according to the FIXME in
the definition of the class PointerUnion.
This patch does not remove them as they are being used in other
subprojects.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D148449
The function name was misleading - the expectation set both by the name
and by other members of Function (like isDeclaration or isIntrinsic)
would be that the function somehow would "be" "debug info for
profiling". But that's not the case - the property indicates (as the
comment over the declaration also explains) whether debug info should be
emitted (for profiling).
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
The Assignment Tracking debug-info feature is outlined in this RFC:
https://discourse.llvm.org/t/
rfc-assignment-tracking-a-better-way-of-specifying-variable-locations-in-ir
A DIAssignID attachment is debug metadata, so don't drop it.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D133292
Previously reverted in 41f5a0004e442ae71c8e754fdadb4bd1e172fb2d. Fold in
D133576 previously reverted in d29d5ffb6332569e85d5eda5130603bbd8664635.
---
The Assignment Tracking debug-info feature is outlined in this RFC:
https://discourse.llvm.org/t/
rfc-assignment-tracking-a-better-way-of-specifying-variable-locations-in-ir
Overview
It's possible to find intrinsics linked to an instruction by looking at the
MetadataAsValue uses of the attached DIAssignID. That covers instruction ->
intrinsic(s) lookup. Add a global DIAssignID -> instruction(s) map which gives
us the ability to perform intrinsic -> instruction(s) lookup. Add plumbing to
keep the map up to date through optimisations and add utility functions
including two that perform those lookups. Finally, add a unittest.
Details
In llvm/lib/IR/LLVMContextImpl.h add AssignmentIDToInstrs which maps DIAssignID
* attachments to Instruction *s. Because the DIAssignID * is the key we can't
use a TrackingMDNodeRef for it, and therefore cannot easily update the mapping
when a temporary DIAssignID is replaced.
Temporary DIAssignID's are only used in IR parsing to deal with metadata
forward references. Update llvm/lib/AsmParser/LLParser.cpp to avoid using
temporary DIAssignID's for attachments.
In llvm/lib/IR/Metadata.cpp add Instruction::updateDIAssignIDMapping which is
called to remove or add an entry (or both) to AssignmentIDToInstrs. Call this
from Instruction::setMetadata and add a call to setMetadata in Intruction's
dtor that explicitly unsets the DIAssignID so that the mappging gets updated.
In llvm/lib/IR/DebugInfo.cpp and DebugInfo.h add utility functions:
getAssignmentInsts(const DbgAssignIntrinsic *DAI)
getAssignmentMarkers(const Instruction *Inst)
RAUW(DIAssignID *Old, DIAssignID *New)
deleteAll(Function *F)
deleteAssignmentMarkers(const Instruction *Inst)
These core utils are tested in llvm/unittests/IR/DebugInfoTest.cpp.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D132224
This reverts commit 171f7024cc82e8702abebdedb699d37b50574be7.
Reverting this patch because it causes a cyclic dependency in the module build
https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/48197/consoleFull#-69937453049ba4694-19c4-4d7e-bec5-911270d8a58c
In file included from <module-includes>:1:
/Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/include/llvm/IR/Argument.h:18:10: fatal error: cyclic dependency in module 'LLVM_IR': LLVM_IR -> LLVM_intrinsic_gen -> LLVM_IR
^
While building module 'LLVM_MC' imported from /Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/lib/MC/MCAsmInfoCOFF.cpp:14:
While building module 'LLVM_IR' imported from /Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/include/llvm/MC/MCPseudoProbe.h:57:
In file included from <module-includes>:12:
/Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/include/llvm/IR/DebugInfo.h:24:10: fatal error: could not build module 'LLVM_intrinsic_gen'
~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
While building module 'LLVM_MC' imported from /Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/lib/MC/MCAsmInfoCOFF.cpp:14:
In file included from <module-includes>:15:
In file included from /Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/include/llvm/MC/MCContext.h:23:
/Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/include/llvm/MC/MCPseudoProbe.h:57:10: fatal error: could not build module 'LLVM_IR'
~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
/Users/buildslave/jenkins/workspace/lldb-cmake/llvm-project/llvm/lib/MC/MCAsmInfoCOFF.cpp:14:10: fatal error: could not build module 'LLVM_MC'
~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
4 errors generated.
The Assignment Tracking debug-info feature is outlined in this RFC:
https://discourse.llvm.org/t/
rfc-assignment-tracking-a-better-way-of-specifying-variable-locations-in-ir
Overview
It's possible to find intrinsics linked to an instruction by looking at the
MetadataAsValue uses of the attached DIAssignID. That covers instruction ->
intrinsic(s) lookup. Add a global DIAssignID -> instruction(s) map which gives
us the ability to perform intrinsic -> instruction(s) lookup. Add plumbing to
keep the map up to date through optimisations and add utility functions
including two that perform those lookups. Finally, add a unittest.
Details
In llvm/lib/IR/LLVMContextImpl.h add AssignmentIDToInstrs which maps DIAssignID
* attachments to Instruction *s. Because the DIAssignID * is the key we can't
use a TrackingMDNodeRef for it, and therefore cannot easily update the mapping
when a temporary DIAssignID is replaced.
Temporary DIAssignID's are only used in IR parsing to deal with metadata
forward references. Update llvm/lib/AsmParser/LLParser.cpp to avoid using
temporary DIAssignID's for attachments.
In llvm/lib/IR/Metadata.cpp add Instruction::updateDIAssignIDMapping which is
called to remove or add an entry (or both) to AssignmentIDToInstrs. Call this
from Instruction::setMetadata and add a call to setMetadata in Intruction's
dtor that explicitly unsets the DIAssignID so that the mappging gets updated.
In llvm/lib/IR/DebugInfo.cpp and DebugInfo.h add utility functions:
getAssignmentInsts(const DbgAssignIntrinsic *DAI)
getAssignmentMarkers(const Instruction *Inst)
RAUW(DIAssignID *Old, DIAssignID *New)
deleteAll(Function *F)
These core utils are tested in llvm/unittests/IR/DebugInfoTest.cpp.
Reviewed By: jmorse
Differential Revision: https://reviews.llvm.org/D132224
In this patch we replace common code patterns with the use of utility
functions for dealing with profiling metadata. There should be no change
in functionality, as the existing checks should be preserved in all
cases.
Reviewed By: bogner, davidxl
Differential Revision: https://reviews.llvm.org/D128860
In this patch we replace common code patterns with the use of utility
functions for dealing with profiling metadata. There should be no change
in functionality, as the existing checks should be preserved in all
cases.
Reviewed By: bogner, davidxl
Differential Revision: https://reviews.llvm.org/D128860
The goal of this change is fixing most of compile time slowdown seen after a630ea3003 commit on lencod and sqlite3 benchmarks.
There are 3 improvements included in this patch:
1. In getNumOperands when possible get value directly from SmallNumOps.
2. Inline getLargePtr by moving its definition to header.
3. In TBAAStructTypeNode::getField get all operands once instead taking operands in loop one after one.
Differential Revision: https://reviews.llvm.org/D129468
Fixed a bug with double destruction of operands and corrected a test issue.
Note that this patch leads to a slight increase in compile time (I measured
about .3%) and a slight increase in memory usage. The increased memory usage
should be offset once resizing is used to a larger extent.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D125998
A change to the allocation characteristics of MDNodes, introducing the ability
to add operands one at a time. This functionality is restricted to MDTuples.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D125998
This patch is refactoring the allocation, initialization and deletion
of MDNodes. It is intended as a preparatory patch for the upcoming
addition of dynamic resizability of MDNodes. It is fundamentally NFC,
but removes the necessity for suppressing the memory sanitizer for
MDNode's operator delete.
Reviewers: dexonsmith
Differential Revision: https://reviews.llvm.org/D125489
Based on the output of include-what-you-use.
This is a big chunk of changes. It is very likely to break downstream code
unless they took a lot of care in avoiding hidden ehader dependencies, something
the LLVM codebase doesn't do that well :-/
I've tried to summarize the biggest change below:
- llvm/include/llvm-c/Core.h: no longer includes llvm-c/ErrorHandling.h
- llvm/IR/DIBuilder.h no longer includes llvm/IR/DebugInfo.h
- llvm/IR/IRBuilder.h no longer includes llvm/IR/IntrinsicInst.h
- llvm/IR/LLVMRemarkStreamer.h no longer includes llvm/Support/ToolOutputFile.h
- llvm/IR/LegacyPassManager.h no longer include llvm/Pass.h
- llvm/IR/Type.h no longer includes llvm/ADT/SmallPtrSet.h
- llvm/IR/PassManager.h no longer includes llvm/Pass.h nor llvm/Support/Debug.h
And the usual count of preprocessed lines:
$ clang++ -E -Iinclude -I../llvm/include ../llvm/lib/IR/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
before: 6400831
after: 6189948
200k lines less to process is no that bad ;-)
Discourse thread on the topic: https://llvm.discourse.group/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D118652
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:
* DIExpression can currently be parsed from IR or read from bitcode
as `distinct`, but this property is silently dropped when printing
to IR. This causes accepted IR to fail to round-trip. As DIExpression
appears inline at each use in the canonical form of IR, it cannot
actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
restricted to only appearing in contexts where there is no syntax for
`distinct`, but for consistency it is treated equivalently to
DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
along with adding general support for the inverse restriction I went
ahead and described this in Metadata.def and updated the parser to be
general. Future nodes which have this restriction can share this
support.
The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.
The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.
A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:
!named = !{!0}
!0 = !DIExpression()
Instead we would only accept the equivalent inlined version:
!named = !{!DIExpression()}
This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:
!named = !{!0}
; error: 'distinct' not allowed for !DIExpression()
!0 = distinct !DIExpression()
Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.
Reviewed By: StephenTozer, t-tye
Differential Revision: https://reviews.llvm.org/D104827
This reverts commit 8cd35ad854ab4458fd509447359066ea3578b494.
It breaks `TestMembersAndLocalsWithSameName.py` on GreenDragon and
Mikael Holmén points out in D104827 that bitcode files created with the
patch cannot be parsed with binaries built before it.
Add UNIQUED and DISTINCT properties in Metadata.def and use them to
implement restrictions on the `distinct` property of MDNodes:
* DIExpression can currently be parsed from IR or read from bitcode
as `distinct`, but this property is silently dropped when printing
to IR. This causes accepted IR to fail to round-trip. As DIExpression
appears inline at each use in the canonical form of IR, it cannot
actually be `distinct` anyway, as there is no syntax to describe it.
* Similarly, DIArgList is conceptually always uniqued. It is currently
restricted to only appearing in contexts where there is no syntax for
`distinct`, but for consistency it is treated equivalently to
DIExpression in this patch.
* DICompileUnit is already restricted to always being `distinct`, but
along with adding general support for the inverse restriction I went
ahead and described this in Metadata.def and updated the parser to be
general. Future nodes which have this restriction can share this
support.
The new UNIQUED property applies to DIExpression and DIArgList, and
forbids them to be `distinct`. It also implies they are canonically
printed inline at each use, rather than via MDNode ID.
The new DISTINCT property applies to DICompileUnit, and requires it to
be `distinct`.
A potential alternative change is to forbid the non-inline syntax for
DIExpression entirely, as is done with DIArgList implicitly by requiring
it appear in the context of a function. For example, we would forbid:
!named = !{!0}
!0 = !DIExpression()
Instead we would only accept the equivalent inlined version:
!named = !{!DIExpression()}
This essentially removes the ability to create a `distinct` DIExpression
by construction, as there is no syntax for `distinct` inline. If this
patch is accepted as-is, the result would be that the non-canonical
version is accepted, but the following would be an error and produce a diagnostic:
!named = !{!0}
; error: 'distinct' not allowed for !DIExpression()
!0 = distinct !DIExpression()
Also update some documentation to consistently use the inline syntax for
DIExpression, and to describe the restrictions on `distinct` for nodes
where applicable.
Reviewed By: StephenTozer, t-tye
Differential Revision: https://reviews.llvm.org/D104827
