Commit Graph

122 Commits

Author SHA1 Message Date
Owen Anderson
bd84bdb2be Move the name pointer out of Value into a map that lives on the
LLVMContext.  Production builds of clang do not set names on most
Value's, so this is wasted space on almost all subclasses of Value.
This reduces the size of all Value subclasses by 8 bytes on 64 bit
hosts.

The one tricky part of this change is averting compile time regression
by keeping Value::hasName() fast.  This required stealing bits out of
NumOperands.

With this change, peak memory usage on verify-uselistorder-nodbg.lto.bc
is decreased by approximately 2.3% (~3MB absolute on my machine).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238791 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-01 22:24:01 +00:00
Duncan P. N. Exon Smith
eb79bb6e61 IR: Add Function metadata attachments
Add IR support for `Metadata` attachments.  Assembly and bitcode support
will follow shortly, but for now we just have unit tests.  This is part
of PR23340.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235783 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-24 21:51:02 +00:00
Duncan P. N. Exon Smith
223d9cfd30 IR: Extract set logic from Instruction attachments, NFC
Extract the set logic for metadata attachments from `Instruction` so it
can be reused for `Function` (PR23340).

This data structure makes a `SmallVector<>` look (a little) like a map,
just doing the bare minimum to support the `Instruction` (and soon,
`Function`) metadata API.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235769 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-24 20:36:25 +00:00
Duncan P. N. Exon Smith
9cd7a4b72d IR: Use remove_if for Instruction::dropUnknownMetadata()
Technically the operations are different -- the old logic moved items
from the back into the opened-up slots, instead of the usual
`remove_if()` logic of a slow and a fast iterator -- but unless a
profile tells us otherwise I prefer the simpler logic here.  Regardless,
there shouldn't be an observable function change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235767 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-24 20:23:44 +00:00
Duncan P. N. Exon Smith
d8c574a5a4 IR: Remove MDMapTy and MDPairTy typedefs, NFC
Remove some typedefs in preparation for factoring out attachment logic
from `Instruction`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235764 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-24 20:19:13 +00:00
Duncan P. N. Exon Smith
4eae7e061e IR: Rename LLVMContextImpl::MetadataStore to InstructionMetadata
Rename `MetadataStore` to the more explicit `InstructionMetadata`.  This
will make room for `FunctionMetadata` (start of PR23340).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235763 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-24 20:16:42 +00:00
Duncan P. N. Exon Smith
f067a68207 IR: Enable uniquing callbacks during MDNode::replaceWithUniqued()
Uniqued nodes have more complete registration with
`ReplaceableMetadataImpl` so that they can update themselves when
operands change.  Fix a bug where `MDNode::replaceWithUniqued()` wasn't
enabling these callbacks.

The two most obvious ways missing callbacks causes problems is that
auto-resolution fails and re-uniquing (on changed operands) just doesn't
happen.  I've added tests for both -- in both cases, I confirmed that
the final check was failing before the fix.

rdar://problem/20365935

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233751 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-31 20:50:50 +00:00
Duncan P. N. Exon Smith
39acf8f243 IR: Use the new DebugLoc API, NFC
Update lib/IR and lib/Bitcode to use the new `DebugLoc` API.  Added an
explicit conversion to `bool` (avoiding a conversion to `MDLocation`),
since a couple of these use cases need to handle broken code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233585 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-30 19:40:05 +00:00
Duncan P. N. Exon Smith
027898a77a IR: Add MDNode::replaceWithPermanent()
Add new API for converting temporaries that may self-reference.
Self-referencing nodes are not allowed to be uniqued, so sending them
into `replaceWithUniqued()` is dangerous (and this commit adds
assertions that prevent it).

`replaceWithPermanent()` has similar semantics to `get()` followed by
calls to `replaceOperandWith()`.  In particular, if there's a
self-reference, it returns a distinct node; otherwise, it returns a
uniqued one.  Like `replaceWithUniqued()` and `replaceWithDistinct()`
(well, it calls out to them) it mutates the temporary node in place if
possible, only calling `replaceAllUsesWith()` on a uniquing collision.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228726 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-10 19:13:46 +00:00
Benjamin Kramer
15307c3eb2 Metadata: Use <algorithm> to simplify code. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228550 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-08 21:56:09 +00:00
Bjorn Steinbrink
61a16d2a16 Correctly combine alias.scope metadata by a union instead of intersecting
Summary:
The alias.scope metadata represents sets of things an instruction might
alias with. When generically combining the metadata from two
instructions the result must be the union of the original sets, because
the new instruction might alias with anything any of the original
instructions aliased with.

Reviewers: hfinkel

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D7490

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228525 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-08 17:07:14 +00:00
Duncan P. N. Exon Smith
ca8d3bf8af IR: Split out DebugInfoMetadata.h, NFC
Move debug-info-centred `Metadata` subclasses into their own
header/source file.  A couple of private template functions are needed
from both `Metadata.cpp` and `DebugInfoMetadata.cpp`, so I've moved them
to `lib/IR/MetadataImpl.h`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227835 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 18:53:21 +00:00
Duncan P. N. Exon Smith
0784a4dabb Fix some file headers, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227826 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-02 18:20:15 +00:00
Duncan P. N. Exon Smith
a791aea5ae IR: Change GenericDwarfNode::getHeader() to StringRef
Simplify the API to use a `StringRef` directly rather than exposing the
`MDString` bits underneath.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226876 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 23:10:55 +00:00
Duncan P. N. Exon Smith
cee1699e9f IR: DwarfNode => DebugNode, NFC
These things are potentially used for non-DWARF data (see the discussion
in PR22235), so take the `Dwarf` out of the name.  Since the new name
gives fewer clues, update the doxygen to properly describe what they
are.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226874 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 22:47:44 +00:00
Duncan P. N. Exon Smith
003346177c IR: Update references to temporaries before deleting
During `MDNode::deleteTemporary()`, call `replaceAllUsesWith(nullptr)`
to update all tracking references to `nullptr`.

This fixes PR22280, where inverted destruction order between tracking
references and the temporaries themselves caused a use-after-free in
`LLParser`.

An alternative fix would be to add an assertion that there are no users,
and continue to fix inverted destruction order in clients (like
`LLParser`), but instead I decided to make getting-teardown-right easy.
(If someone disagrees let me know.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226866 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 21:36:45 +00:00
Duncan P. N. Exon Smith
749d6fbf7e IR: Move MDNode clone() methods from ValueMapper to MDNode, NFC
Now that the clone methods used by `MapMetadata()` don't do any
remapping (and return a temporary), they make more sense as member
functions on `MDNode` (and subclasses).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226541 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-20 02:56:57 +00:00
Duncan P. N. Exon Smith
62475afaf2 IR: Canonicalize GenericDwarfNode empty headers to null
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226532 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-20 00:58:46 +00:00
Duncan P. N. Exon Smith
c10ef2df5c IR: Detect whether to call recalculateHash() via SFINAE, NFC
Rather than relying on updating switch statements correctly, detect
whether `setHash()` exists in the subclass.  If so, call
`recalculateHash()` and `setHash(0)` appropriately.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226531 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-20 00:57:33 +00:00
Duncan P. N. Exon Smith
0a9f921686 IR: Introduce GenericDwarfNode
As part of PR22235, introduce `DwarfNode` and `GenericDwarfNode`.  The
former is a metadata node with a DWARF tag.  The latter matches our
current (generic) schema of a header with string (and stringified
integer) data and an arbitrary number of operands.

This doesn't move it into place yet; that change will require a large
number of testcase updates.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226529 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-20 00:01:43 +00:00
Duncan P. N. Exon Smith
0d7ab29889 IR: Cleanup MDNode field use, NFC
Swap usage of `SubclassData32` and `MDNodeSubclassData`, and rename
`MDNodeSubclassData` to `NumUnresolved`.  Small drive-by cleanup to
`countUnresolvedOperands()` since otherwise the name clash with local
vars named `NumUnresolved` would be confusing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226523 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 23:18:34 +00:00
Duncan P. N. Exon Smith
c062fbe4ca IR: Move replaceWithUniqued(), etc., to source file, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226522 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 23:17:09 +00:00
Duncan P. N. Exon Smith
898c48822f IR: Cleanup MDNode::MDNode(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226521 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 23:15:21 +00:00
Duncan P. N. Exon Smith
b0617860b5 IR: Merge UniquableMDNode back into MDNode, NFC
As pointed out in r226501, the distinction between `MDNode` and
`UniquableMDNode` is confusing.  When we need subclasses of `MDNode`
that don't use all its functionality it might make sense to break it
apart again, but until then this makes the code clearer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226520 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 23:13:14 +00:00
Duncan P. N. Exon Smith
fce53dd939 IR: Extract MDNodeOpsKey, NFC
Make the MDTuple operand hashing logic reusable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226519 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 22:53:18 +00:00
Duncan P. N. Exon Smith
ce8f144e00 IR: Simplify uniquifyImpl(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226518 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 22:52:07 +00:00
Duncan P. N. Exon Smith
668bd8ccfe IR: Simplify erasing from uniquing store, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226517 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 22:47:08 +00:00
Duncan P. N. Exon Smith
37c7ccc40c IR: Allow temporary nodes to become uniqued or distinct
Add `MDNode::replaceWithUniqued()` and `MDNode::replaceWithDistinct()`,
which mutate temporary nodes to become uniqued or distinct.  On uniquing
collisions, the unique version is returned and the node is deleted.

This takes advantage of temporary nodes being folded back in, and should
let me clean up some awkward logic in `MapMetadata()`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226510 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 22:24:52 +00:00
Duncan P. N. Exon Smith
0927997ce8 IR: Split out countUnresolvedOperands(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226508 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 22:18:29 +00:00
Duncan P. N. Exon Smith
8ec0aee3b4 IR: Remove MDNodeFwdDecl
Remove `MDNodeFwdDecl` (as promised in r226481).  Aside from API
changes, there's no real functionality change here.
`MDNode::getTemporary()` now forwards to `MDTuple::getTemporary()`,
which returns a tuple with `isTemporary()` equal to true.

The main point is that we can now add temporaries of other `MDNode`
subclasses, needed for PR22235 (I introduced `MDNodeFwdDecl` in the
first place because I didn't recognize this need, and thought they were
only needed to handle forward references).

A few things left out of (or highlighted by) this commit:

  - I've had to remove the (few) uses of `std::unique_ptr<>` to deal
    with temporaries, since the destructor is no longer public.
    `getTemporary()` should probably return the equivalent of
    `std::unique_ptr<T, MDNode::deleteTemporary>`.
  - `MDLocation::getTemporary()` doesn't exist yet (worse, it actually
    does exist, but does the wrong thing: `MDNode::getTemporary()` is
    inherited and returns an `MDTuple`).
  - `MDNode` now only has one subclass, `UniquableMDNode`, and the
    distinction between them is actually somewhat confusing.

I'll fix those up next.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226501 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 20:36:39 +00:00
Duncan P. N. Exon Smith
e5afc6570f IR: Extract out and reuse storeImpl(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226499 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 20:18:13 +00:00
Duncan P. N. Exon Smith
1c588db19b IR: Extract out getUniqued(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226498 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 20:16:50 +00:00
Duncan P. N. Exon Smith
518025f8a1 IR: Reuse getImpl() for getDistinct(), NFC
Merge `getDistinct()`'s implementation with those of `get()` and
`getIfExists()` for both `MDTuple` and `MDLocation`.  This will make it
easier to scale to supporting temporaries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226497 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 20:14:15 +00:00
Duncan P. N. Exon Smith
e85df9e0a2 IR: Simplify MDNode::setOperand(), NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226492 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 19:29:25 +00:00
Duncan P. N. Exon Smith
e2644b68c1 IR: Simplify handleChangedOperand() fast path, NFC
Use `isUniqued()` instead of `isStoredDistinctInContext()`, and remove
an assertion that won't be valid once temporaries are merged back in.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226491 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 19:28:28 +00:00
Duncan P. N. Exon Smith
5cc26e0d4b IR: Remove direct comparisons against Metadata::Storage, NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226490 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 19:26:24 +00:00
Duncan P. N. Exon Smith
2c22f8dc09 IR: Assert that resolve() is only called on uniqued nodes, NFC
Add an assertion in `UniquableMDNode::resolve()` to prevent temporaries
from being resolved (once they're merged back in).  Needed to shuffle
order of `resolve()` and `storeDistinctInContext()` to prevent it from
firing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226489 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 19:25:33 +00:00
Duncan P. N. Exon Smith
c9a780aec5 IR: Unify code for MDNode::isResolved(), NFC
Unify the definitions of `MDNode::isResolved()` and
`UniquableMDNode::isResolved()`.  Previously, `UniquableMDNode` could
answer this question more efficiently, but now that RAUW support has
been unified with `MDNodeFwdDecl`, `MDNode` doesn't need any casts to
figure out the answer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226485 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 19:03:18 +00:00
Duncan P. N. Exon Smith
641414a6c0 IR: Store RAUW support and Context in the same pointer, NFC
Add an `LLVMContext &` to `ReplaceableMetadataImpl`, create a class that
either holds a reference to an `LLVMContext` or owns a
`ReplaceableMetadataImpl`, and use the new class in `MDNode`.

  - This saves a pointer in `UniquableMDNode` at the cost of a pointer
    in `ValueAsMetadata` (which didn't used to store the `LLVMContext`).
    There are far more of the former.
  - Unifies RAUW support between `MDNodeFwdDecl` (which is going away,
    see r226481) and `UniquableMDNode`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226484 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 19:02:06 +00:00
Duncan P. N. Exon Smith
1d72e18caa IR: Add isUniqued() and isTemporary()
Change `MDNode::isDistinct()` to only apply to 'distinct' nodes (not
temporaries), and introduce `MDNode::isUniqued()` and
`MDNode::isTemporary()` for the other two possibilities.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226482 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 18:45:35 +00:00
Duncan P. N. Exon Smith
5f50874b3d IR: Use an enum to describe Metadata storage, NFC
More clearly describe the type of storage used for `Metadata`.

  - `Uniqued`: uniqued, stored in the context.
  - `Distinct`: distinct, stored in the context.
  - `Temporary`: not owned by anyone.

This is the first in a series of commits to fix a design problem with
`MDNodeFwdDecl` that I need to solve for PR22235.  While `MDNodeFwdDecl`
works well as a forward declaration, we use `MDNode::getTemporary()` for
more than forward declarations -- we also need to create early versions
of nodes (with fields not filled in) that we'll fill out later (see
`DIBuilder::finalize()` and `CGDebugInfo::finalize()` for examples).
This was a blind spot I had when I introduced `MDNodeFwdDecl` (which
David Blaikie (indirectly) highlighted in an unrelated review [1]).

[1]: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20150112/252381.html

In general, we need `MDTuple::getTemporary()` to give a temporary tuple
(like `MDNodeFwdDecl`), `MDLocation::getTemporary()` to give a temporary
location, and (the problem at hand) `GenericDebugMDNode::getTemporary()`
to give a temporary generic debug node.

So I need to fold the idea of "temporary" nodes back into
`UniquableMDNode`.  (More commits to follow as I refactor.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226481 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 18:36:18 +00:00
Duncan P. N. Exon Smith
fb7514fccb IR: Allow 16-bits for column info
Raise the limit for column information from 8 bits to 16 bits.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226291 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-16 17:33:08 +00:00
Duncan P. N. Exon Smith
9e4a11f46c IR: Fix a use-after-free in RAUW
Happened pretty commonly during `LLVMContext` teardown when `clang -g`
hit an error.  This fixes the use-after-free.  Next I'll clean up
teardown so that it's not RAUW'ing when metadata-tracked values are
deleted (only really causes a problem if the graph is mid-construction
when teardown starts, but it's still unnecessary work).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226029 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 19:56:10 +00:00
Duncan P. N. Exon Smith
d640962656 IR: Add MDLocation class
Add a new subclass of `UniquableMDNode`, `MDLocation`.  This will be the
IR version of `DebugLoc` and `DILocation`.  The goal is to rename this
to `DILocation` once the IR classes supersede the `DI`-prefixed
wrappers.

This isn't used anywhere yet.  Part of PR21433.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225824 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 20:44:56 +00:00
Duncan P. N. Exon Smith
698be08c84 IR: Remove an invalid assertion when replacing resolved operands
This adds back the testcase from r225738, and adds to it.  Looks like we
need both sides for now (the assertion was incorrect both ways, and
although it seemed reasonable (when written correctly) it wasn't
particularly important).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225745 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 00:46:34 +00:00
Duncan P. N. Exon Smith
47952358ce Revert "IR: Fix an inverted assertion when replacing resolved operands"
This reverts commit r225738.  Maybe the assertion is just plain wrong,
but this version fails on WAY more bots.  I'll make sure both ways work
in a follow-up but I want to get bots green in the meantime.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225742 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 00:34:21 +00:00
Duncan P. N. Exon Smith
4fef722974 IR: Fix an inverted assertion when replacing resolved operands
Add a unit test, since this bug was only exposed by clang tests.  Thanks
to Rafael for tracking this down!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225738 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 00:10:38 +00:00
Duncan P. N. Exon Smith
343bb3e252 IR: Prepare for a new UniquableMDNode subclass, NFC
Add generic dispatch for the parts of `UniquableMDNode` that cast to
`MDTuple`.  This makes adding other subclasses (like PR21433's
`MDLocation`) easier.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225697 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 20:56:33 +00:00
Duncan P. N. Exon Smith
d1ec4f037d IR: Stop erasing MDNodes from uniquing sets during teardown
Stop erasing `MDNode`s from the uniquing sets in `LLVMContextImpl`
during teardown (in particular, during
`UniquableMDNode::~UniquableMDNode()`).  Although it's currently
feasible, there isn't any clear benefit and it may not be feasible for
other subclasses (which don't explicitly store the lookup hash).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225696 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 20:50:25 +00:00
Duncan P. N. Exon Smith
c88b471b9d IR: Move creation logic to MDNodeFwdDecl, NFC
Same as with `MDTuple`, factor out a `friend MDNode` by moving creation
logic to the concrete subclass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225690 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 20:21:37 +00:00