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Commit Graph

614 Commits

Author SHA1 Message Date
Sanjay Patel
21f1293d28 [DAG] add helper to bind memop chains; NFCI
This step is just intended to reduce code duplication rather than change any functionality.

A follow-up would be to replace PPCTargetLowering::spliceIntoChain() usage with this new helper.

Differential Revision: https://reviews.llvm.org/D33649

llvm-svn: 305192
2017-06-12 14:41:48 +00:00
Simon Pilgrim
18db4739a5 [DAG] Move SelectionDAG::isCommutativeBinOp to TargetLowering.
This will allow commutation of target-specific DAG nodes in future patches

Differential Revision: https://reviews.llvm.org/D33882

llvm-svn: 304911
2017-06-07 14:05:04 +00:00
Chandler Carruth
eb66b33867 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Eugene Zelenko
1fc3a501cc [CodeGen] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 304621
2017-06-03 00:22:41 +00:00
Andrew Kaylor
6f9f9c2fbe Add constrained intrinsics for some libm-equivalent operations
Differential revision: https://reviews.llvm.org/D32319

llvm-svn: 303922
2017-05-25 21:31:00 +00:00
Ahmed Bougacha
d74b69039b [CodeGen] Don't require AA in SDAGISel at -O0.
Before r247167, the pass manager builder controlled which AA
implementations were used, exporting them all in the AliasAnalysis
analysis group.

Now, AAResultsWrapperPass always uses BasicAA, but still uses other AA
implementations if made available in the pass pipeline.

But regardless, SDAGISel is required at O0, and really doesn't need to
be doing fancy optimizations based on useful AA results.

Don't require AA at CodeGenOpt::None, and only use it otherwise.

This does have a functional impact (and one testcase is pessimized
because we can't reuse a load).  But I think that's desirable no matter
what.

Note that this alone doesn't result in less DT computations: TwoAddress
was previously able to reuse the DT we computed for SDAG.  That will be
fixed separately.

Differential Revision: https://reviews.llvm.org/D32766

llvm-svn: 302611
2017-05-10 00:39:30 +00:00
Serge Pavlov
b8ce9ec478 Add extra operand to CALLSEQ_START to keep frame part set up previously
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to  CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.

This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.

The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
  affects all targets that use frame pseudo instructions and touched many
  files although the changes are uniform.
- Access to frame properties are implemented using special instructions
  rather than calls getOperand(N).getImm(). For X86 and ARM such
  replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
  instruction. These involve proper instruction initialization and
  methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
  frame parts initialized inside frame instruction pair and outside it.

The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.

Differential Revision: https://reviews.llvm.org/D32394

llvm-svn: 302527
2017-05-09 13:35:13 +00:00
Simon Pilgrim
9d13cd153b [SelectionDAG] Improve support for promotion of <1 x fX> floating point argument types (PR31088)
PR31088 demonstrated that we were assuming that only integers require promotion from <1 x iX> types, when in fact float types may require it as well - in this case half floats.

This patch adds support for extension/truncation for both integer and float types.

Differential Revision: https://reviews.llvm.org/D32391

llvm-svn: 301910
2017-05-02 10:33:08 +00:00
Amara Emerson
7b62022bef Generalize the specialized flag-carrying SDNodes by moving flags into SDNode.
This removes BinaryWithFlagsSDNode, and flags are now all passed by value.

Differential Revision: https://reviews.llvm.org/D32527

llvm-svn: 301803
2017-05-01 15:17:51 +00:00
Craig Topper
af680f3cea [SelectionDAG] Use KnownBits struct in DAG's computeKnownBits and simplifyDemandedBits
This patch replaces the separate APInts for KnownZero/KnownOne with a single KnownBits struct. This is similar to what was done to ValueTracking's version recently.

This is largely a mechanical transformation from KnownZero to Known.Zero.

Differential Revision: https://reviews.llvm.org/D32569

llvm-svn: 301620
2017-04-28 05:31:46 +00:00
Simon Pilgrim
699907d518 [SelectionDAG] Added getBuildVector(ArrayRef<SDUse>) helper.
llvm-svn: 301322
2017-04-25 16:41:28 +00:00
Simon Pilgrim
026e8c9b44 [DAGCombiner] Add vector demanded elements support to ComputeNumSignBits
Currently ComputeNumSignBits returns the minimum number of sign bits for all elements of vector data, when we may only be interested in one/some of the elements.

This patch adds a DemandedElts argument that allows us to specify the elements we actually care about. The original ComputeNumSignBits implementation calls with a DemandedElts demanding all elements to match current behaviour. Scalar types set this to 1.

I've only added support for BUILD_VECTOR and EXTRACT_VECTOR_ELT so far, all others will default to demanding all elements but can be updated in due course.

Followup to D25691.

Differential Revision: https://reviews.llvm.org/D31311

llvm-svn: 299219
2017-03-31 13:54:09 +00:00
Ahmed Bougacha
6e6c156614 [CodeGen] Pass SDAG an ORE, and replace FastISel stats with remarks.
In the long-term, we want to replace statistics with something
finer-grained that lets us gather per-function data.
Remarks are that replacement.

Create an ORE instance in SelectionDAGISel, and pass it to
SelectionDAG.

SelectionDAG was used so that we can emit remarks from all
SelectionDAG-related code, including TargetLowering and DAGCombiner.
This isn't used in the current patch but Adam tells me he's interested
for the fp-contract combines.

Use the ORE instance to emit FastISel failures as remarks (instead of
the mix of dbgs() dumps and statistics that we currently have).

Eventually, we want to have an API that tells us whether remarks are
enabled (http://llvm.org/PR32352) so that we don't emit expensive
remarks (in this case, dumping IR) when it's not needed.  For now, use
'isEnabled' as a crude replacement.

This does mean that the replacement for '-fast-isel-verbose' is now
'-pass-remarks-missed=isel'.  Additionally, clang users also need to
enable remark diagnostics, using '-Rpass-missed=isel'.

This also removes '-fast-isel-verbose2': there are no static statistics
that we want to only enable in asserts builds, so we can always use
the remarks regardless of the build type.

Differential Revision: https://reviews.llvm.org/D31405

llvm-svn: 299093
2017-03-30 17:49:58 +00:00
Sanjay Patel
de78e1aaa3 [DAG] vector div/rem with any zero element in divisor is undef
This is the backend counterpart to:
https://reviews.llvm.org/rL297390
https://reviews.llvm.org/rL297409
and follow-up to:
https://reviews.llvm.org/rL297384

It surprised me that we need to duplicate the check in FoldConstantArithmetic and FoldConstantVectorArithmetic, 
but one or the other doesn't catch all of the test cases. There is an existing code comment about merging those 
someday.

Differential Revision: https://reviews.llvm.org/D30826

llvm-svn: 297762
2017-03-14 18:06:28 +00:00
Sanjay Patel
f14bbf566d [DAG] add convenience function to get -1 constant; NFCI
llvm-svn: 296004
2017-02-23 19:02:33 +00:00
Amaury Sechet
cc55016d9e [DAGCombiner] Make DAGCombiner smarter about overflow
Summary: Leverage it to transform addc into add.

Reviewers: mkuper, spatel, RKSimon, zvi

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29524

llvm-svn: 294187
2017-02-06 14:54:49 +00:00
Benjamin Kramer
5fd769f791 Apply clang-tidy's performance-unnecessary-value-param to LLVM.
With some minor manual fixes for using function_ref instead of
std::function. No functional change intended.

llvm-svn: 291904
2017-01-13 14:39:03 +00:00
Matt Arsenault
bc8f9b01ec Remove unused CONVERT_RNDSAT intrinsics
llvm-svn: 291607
2017-01-10 22:38:02 +00:00
Matt Arsenault
7363b816c7 DAG: Add helper for testing constant values
There are helpers for testing for constant or constant build_vector,
and for splat ConstantFP vectors, but not for a constantfp or
non-splat ConstantFP vector.

llvm-svn: 290317
2016-12-22 04:39:45 +00:00
Elena Demikhovsky
1759608f50 Added a template for building target specific memory node in DAG.
I added API for creation a target specific memory node in DAG. Today, all memory nodes are common for all targets and their constructors are located in SelectionDAG.cpp.
There are some cases in X86 where we need to create a special node - truncation-with-saturation store, float-to-half-store. 
In the current patch I added truncation-with-saturation nodes and I'm using them for intrinsics. In the future I plan to implement DAG lowering for truncation-with-saturation pattern.

Differential Revision: https://reviews.llvm.org/D27899

llvm-svn: 290250
2016-12-21 10:43:36 +00:00
Joel Jones
5b76390d23 Fix name typo in SelectonDAG
llvm-svn: 289969
2016-12-16 18:22:54 +00:00
Stephan Bergmann
aba15d97df Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Simon Pilgrim
483654e906 [DAGCombiner] (REAPPLIED) Add vector demanded elements support to computeKnownBits
Currently computeKnownBits returns the common known zero/one bits for all elements of vector data, when we may only be interested in one/some of the elements.

This patch adds a DemandedElts argument that allows us to specify the elements we actually care about. The original computeKnownBits implementation calls with a DemandedElts demanding all elements to match current behaviour. Scalar types set this to 1.

The approach was found to be easier than trying to add a per-element known bits solution, for a similar usefulness given the combines where computeKnownBits is typically used.

I've only added support for a few opcodes so far (the ones that have proven straightforward to test), all others will default to demanding all elements but can be updated in due course.

DemandedElts support could similarly be added to computeKnownBitsForTargetNode in a future commit.

This looked like this had caused compile time regressions on some buildbots (and was reverted in rL285381), but appears to have just been a harmless bystander!

Differential Revision: https://reviews.llvm.org/D25691

llvm-svn: 285494
2016-10-29 11:29:39 +00:00
Juergen Ributzka
81c0bcfdd7 Revert "[DAGCombiner] Add vector demanded elements support to computeKnownBits"
This seems to have increased LTO compile time bejond 2x of previous builds.
See http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto/10676/

llvm-svn: 285381
2016-10-28 04:01:12 +00:00
Simon Pilgrim
e1bf270f66 [DAGCombiner] Add vector demanded elements support to computeKnownBits
Currently computeKnownBits returns the common known zero/one bits for all elements of vector data, when we may only be interested in one/some of the elements.

This patch adds a DemandedElts argument that allows us to specify the elements we actually care about. The original computeKnownBits implementation calls with a DemandedElts demanding all elements to match current behaviour. Scalar types set this to 1.

The approach was found to be easier than trying to add a per-element known bits solution, for a similar usefulness given the combines where computeKnownBits is typically used.

I've only added support for a few opcodes so far (the ones that have proven straightforward to test), all others will default to demanding all elements but can be updated in due course.

DemandedElts support could similarly be added to computeKnownBitsForTargetNode in a future commit.

Differential Revision: https://reviews.llvm.org/D25691

llvm-svn: 285296
2016-10-27 14:29:28 +00:00
Benjamin Kramer
7999e6045a Retire llvm::alignOf in favor of C++11 alignof.
No functionality change intended.

llvm-svn: 284733
2016-10-20 15:02:18 +00:00
Konstantin Zhuravlyov
1aefc15a1a [MachineMemOperand] Move synchronization scope and atomic orderings from SDNode to MachineMemOperand, and remove redundant getAtomic* member functions from SelectionDAG.
Differential Revision: https://reviews.llvm.org/D24577

llvm-svn: 284312
2016-10-15 22:01:18 +00:00
Elena Demikhovsky
d561a4f25b DAG: Setting Masked-Expand-Load as a variant of Masked-Load node
Masked-expand-load node represents load operation that loads a variable amount of elements from memory according to amount of "true" bits in the mask and expands the loaded elements according to their position in the mask vector.
Right now, the node is used in intrinsics for VEXPAND* instructions. 
The work is done towards implementation of masked.expandload and masked.compressstore intrinsics.

Differential Revision: https://reviews.llvm.org/D25322

llvm-svn: 283694
2016-10-09 10:48:52 +00:00
Vedant Kumar
3ccb460d6b Delete some dead code in SelectionDAG (NFC)
Differential Revision: https://reviews.llvm.org/D24435

llvm-svn: 283505
2016-10-06 22:53:43 +00:00
Ayman Musa
a9677386d1 [X86][avx512] Fix bug in masked compress store.
Differential Revision: https://reviews.llvm.org/D23984

llvm-svn: 282381
2016-09-26 06:22:08 +00:00
Duncan P. N. Exon Smith
0410d4f82c ADT: Never allocate nodes in iplist<> and ilist<>
Remove createNode() and any API that depending on it, and add
HasCreateNode to the list of checks for HasObsoleteCustomizations.  Now
an ilist *never* allocates (this was already true for iplist).

This factors out all the differences between iplist and ilist.  I'll aim
to rename both to "owning_ilist" eventually, to call out the interesting
(not exactly intrusive) ownership semantics.  In the meantime, I've left
both names around to reduce code churn.

One of the deleted APIs is the ilist copy constructor.  I've lifted up
and tested iplist::cloneFrom (ala simple_ilist::cloneFrom) as a
replacement.

Users of ilist<> and iplist<> that want the list to allocate nodes have
a few options:
- use std::list;
- use AllocatorList or BumpPtrList (or build a similarly trivial list);
- use cloneFrom (which is explicit at the call site); or
- allocate at the call site.

See r280573, r281177, r281181, and r281182 for examples of what to do if
you're updating out-of-tree code.

llvm-svn: 281184
2016-09-11 23:43:43 +00:00
Vedant Kumar
26dd41655c Remove dead code in the SelectionDAG headers (NFC)
I tested this with "ninja check-llvm-codegen" on a Release build with
all architectures enabled, and again with a Debug build on x86.

Found with llvm-cov.

Differential Revision: https://reviews.llvm.org/D24433

llvm-svn: 281120
2016-09-10 00:05:19 +00:00
Duncan P. N. Exon Smith
9df0e64f25 ADT: Split ilist_node_traits into alloc and callback, NFC
Many lists want to override only allocation semantics, or callbacks for
iplist.  Split these up to prevent code duplication.
- Specialize ilist_alloc_traits to change the implementations of
  deleteNode() and createNode().
- One common desire is to do nothing deleteNode() and disable
  createNode().  Specialize ilist_alloc_traits to inherit from
  ilist_noalloc_traits for that behaviour.
- Specialize ilist_callback_traits to use the addNodeToList(),
  removeNodeFromList(), and transferNodesFromList() callbacks.

As a drive-by, add some coverage to the callback-related unit tests.

llvm-svn: 280128
2016-08-30 18:40:47 +00:00
Justin Lebar
75ed28e4bb [SelectionDAG] Use a union of bitfield structs for SDNode::SubclassData.
Summary:
This greatly simplifies our handling of SDNode::SubclassData.

NFC, hopefully.  :)

See discussion in D23035 for discussion about the design API of these
bitfields.

Reviewers: chandlerc

Subscribers: llvm-commits, rnk

Differential Revision: https://reviews.llvm.org/D23036

llvm-svn: 279537
2016-08-23 17:18:11 +00:00
Duncan P. N. Exon Smith
68b6058de5 ADT: Remove ilist_*sentinel_traits, NFC
Remove all the dead code around ilist_*sentinel_traits.  This is a
follow-up to gutting them as part of r279314 (originally r278974),
staged to prevent broken builds in sub-projects.

Uses were removed from clang in r279457 and lld in r279458.

llvm-svn: 279473
2016-08-22 20:51:00 +00:00
Tim Shen
823bde34b3 [GraphTraits] Make nodes_iterator dereference to NodeType*/NodeRef
Currently nodes_iterator may dereference to a NodeType* or a NodeType&. Make them all dereference to NodeType*, which is NodeRef later.

Differential Revision: https://reviews.llvm.org/D23704
Differential Revision: https://reviews.llvm.org/D23705

llvm-svn: 279326
2016-08-19 21:20:13 +00:00
Duncan P. N. Exon Smith
2e8f72520b ADT: Share code for embedded sentinel traits, NFC
Share code for the (mostly problematic) embedded sentinel traits.
- Move the LLVM_NO_SANITIZE("object-size") attribute to
  ilist_half_embedded_sentinel_traits and ilist_embedded_sentinel_traits
  (previously it spread throughout the code duplication).
- Add an ilist_full_embedded_sentinel_traits which has no UB (but has
  the downside of storing the complete node).
- Replace all the custom sentinel traits in LLVM with a declaration of
  ilist_sentinel_traits that inherits from one of the embedded sentinel
  traits classes.

There are still custom sentinel traits in other LLVM subprojects.  I'll
remove those in a follow-up.

Nothing at all should be changing here, this is just rearranging code.
Note that the final goal here is to remove the sentinel traits
altogether, settling on the memory layout of
ilist_half_embedded_sentinel_traits without the UB.  This intermediate
step moves the logic into ilist.h.

llvm-svn: 278513
2016-08-12 15:00:55 +00:00
Justin Lebar
4964e23787 [SelectionDAG] Get rid of bool parameters in SelectionDAG::getLoad, getStore, and friends.
Summary:
Instead, we take a single flags arg (a bitset).

Also add a default 0 alignment, and change the order of arguments so the
alignment comes before the flags.

This greatly simplifies many callsites, and fixes a bug in
AMDGPUISelLowering, wherein the order of the args to getLoad was
inverted.  It also greatly simplifies the process of adding another flag
to getLoad.

Reviewers: chandlerc, tstellarAMD

Subscribers: jholewinski, arsenm, jyknight, dsanders, nemanjai, llvm-commits

Differential Revision: http://reviews.llvm.org/D22249

llvm-svn: 275592
2016-07-15 18:27:10 +00:00
Sanjay Patel
6be59af417 fix documentation comments; NFC
llvm-svn: 275101
2016-07-11 20:50:39 +00:00
Craig Topper
0caa8a6b4a [CodeGen,Target] Remove the version of DAG.getVectorShuffle that takes a pointer to a mask array. Convert all callers to use the ArrayRef version. No functional change intended.
For the most part this simplifies all callers. There were two places in X86 that needed an explicit makeArrayRef to shorten a statically sized array.

llvm-svn: 274337
2016-07-01 06:54:47 +00:00
Nirav Dave
de9507c813 Preserve DebugInfo when replacing values in DAGCombiner
Recommiting after correcting over-eager Debug Value transfer fixing PR28270.

[DAG] Previously debug values would transfer debuginfo for the selected
start node for a replacement which allows for debug to be dropped.

Push debug value transfer to occur with node/value replacement in
SelectionDAG, remove now extraneous transfers of debug values.

This refixes PR9817 which was being incompletely checked in the
testsuite.

Reviewers: jyknight

Subscribers: dblaikie, llvm-commits

Differential Revision: http://reviews.llvm.org/D21037

llvm-svn: 273585
2016-06-23 17:52:57 +00:00
Peter Collingbourne
509ed7ea1b Revert r273456, "Preserve DebugInfo when replacing values in DAGCombiner" as it caused pr28270.
llvm-svn: 273518
2016-06-23 00:06:17 +00:00
Nirav Dave
4b5c6b61b9 Preserve DebugInfo when replacing values in DAGCombiner
Recommiting after fixing over-aggressive assertion

[DAG] Previously debug values would transfer debuginfo for the selected
start node for a replacement which allows for debug to be dropped.

Push debug value transfer to occur with node/value replacement in
SelectionDAG, remove now extraneous transfers of debug values.

This refixes PR9817 which was being incompletely checked in the
testsuite.

Reviewers: jyknight

Subscribers: dblaikie, llvm-commits

Differential Revision: http://reviews.llvm.org/D21037

llvm-svn: 273456
2016-06-22 19:03:26 +00:00
Benjamin Kramer
0d4a698a65 Apply another batch of fixes from clang-tidy's performance-unnecessary-value-param.
Contains some manual fixes. No functionality change intended.

llvm-svn: 273047
2016-06-17 20:41:14 +00:00
Nirav Dave
51f5fcb25e Revert "Preserve DebugInfo when replacing values in DAGCombiner"
Reverting due to assertion failure in
lib/CodeGen/SelectionDAG/InstrEmitter.cpp

This reverts commit r272792.

llvm-svn: 272799
2016-06-15 16:08:50 +00:00
Nirav Dave
e4e3dbf021 Preserve DebugInfo when replacing values in DAGCombiner
[DAG] Previously debug values would transfer debuginfo for the selected
start node for a replacement which allows for debug to be dropped.

Push debug value transfer to occur with node/value replacement in
SelectionDAG, remove now extraneous transfers of debug values.

This refixes PR9817 which was being incompletely checked in the
testsuite.

Reviewers: jyknight

Subscribers: dblaikie, llvm-commits

Differential Revision: http://reviews.llvm.org/D21037

llvm-svn: 272792
2016-06-15 14:50:08 +00:00
Benjamin Kramer
e80783f62f Pass DebugLoc and SDLoc by const ref.
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512
2016-06-12 15:39:02 +00:00
Justin Bogner
9dff21f0ab Re-apply "SDAG: Update ChainNodesMatched as nodes are deleted"
My first attempt at this had an overly aggressive assert - chain nodes
will only be removed, but we could hit the assert if a non-chain node
was CSE'd (NodeToMatch, for instance).

This reapplies r271706 by reverting r271713 and fixing an assert.

Original message:

Avoid relying on UB by looking into deleted nodes for a marker value.
Instead, update the list of chain nodes as we go.

llvm-svn: 271733
2016-06-03 20:47:40 +00:00
Justin Bogner
ad5fb47222 Revert "SDAG: Update ChainNodesMatched as nodes are deleted"
Seeing failures in CodeGen/Generic/icmp-illegal.ll on quite a few
bots.

This reverts r271706.

llvm-svn: 271713
2016-06-03 19:40:06 +00:00
Justin Bogner
21c0bc722b SDAG: Update ChainNodesMatched as nodes are deleted
Avoid relying on UB by looking into deleted nodes for a marker value.
Instead, update the list of chain nodes as we go.

llvm-svn: 271706
2016-06-03 18:50:11 +00:00