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Commit Graph

23974 Commits

Author SHA1 Message Date
Rafael Espindola
d2efd01e25 Use named temporaries for directional labels.
Directional labels can show up in symbol tables (and we have a llvm-mc test for
that). Given that, we need to make sure they are named.

With that out of the way, use setUseNamesOnTempLabels in llvm-mc so that it
too benefits from the memory saving.

llvm-svn: 239914
2015-06-17 16:26:47 +00:00
James Y Knight
8fdb2dc157 Tweak wording of alignment static_assert messages.
llvm-svn: 239907
2015-06-17 13:53:12 +00:00
Igor Breger
545927df8a AVX-512: cvtusi2ss/d intrinsics.
Change builtin function name and signature ( add third parameter - rounding mode ).
Added tests for intrinsics.

Differential Revision: http://reviews.llvm.org/D10473

llvm-svn: 239888
2015-06-17 07:23:57 +00:00
Chandler Carruth
aa98916d54 [PM/AA] Remove the UnknownSize static member from AliasAnalysis.
This is now living in MemoryLocation, which is what it pertains to. It
is also an enum there rather than a static data member which is left
never defined.

llvm-svn: 239886
2015-06-17 07:21:38 +00:00
Chandler Carruth
cc1aae13e7 [PM/AA] Remove the Location typedef from the AliasAnalysis class now
that it is its own entity in the form of MemoryLocation, and update all
the callers.

This is an entirely mechanical change. References to "Location" within
AA subclases become "MemoryLocation", and elsewhere
"AliasAnalysis::Location" becomes "MemoryLocation". Hope that helps
out-of-tree folks update.

llvm-svn: 239885
2015-06-17 07:18:54 +00:00
Chandler Carruth
6ac32c5879 [PM/AA] Split the location computation out of getArgLocation so the
virtual interface on AliasAnalysis only deals with ModRef information.

This interface was both computing memory locations by using TLI and
other tricks to estimate the size of memory referenced by an operand,
and computing ModRef information through similar investigations. This
change narrows the scope of the virtual interface on AliasAnalysis
slightly.

Note that all of this code could live in BasicAA, and be done with
a single investigation of the argument, if it weren't for the fact that
the generic code in AliasAnalysis::getModRefBehavior for a callsite
calls into the virtual aspect of (now) getArgModRefInfo. But this
patch's arrangement seems a not terrible way to go for now.

The other interesting wrinkle is how we could reasonably extend LLVM
with support for custom memory location sizes and mod/ref behavior for
library routines. After discussions with Hal on the review, the
conclusion is that this would be best done by fleshing out the much
desired support for extensions to TLI, and support these types of
queries in that interface where we would likely be doing other library
API recognition and analysis.

Differential Revision: http://reviews.llvm.org/D10259

llvm-svn: 239884
2015-06-17 07:12:40 +00:00
James Y Knight
f3c63ab09b Fix alignment issues in LLVM.
Adds static_asserts to ensure alignment of concatenated objects is
correct, and fixes them where they are not.

Also changes the definition of AlignOf to use constexpr, except on
MSVC, to avoid enum comparison warnings from GCC.

(There's not too much of this in llvm itself, most of the fun is in
clang).

This seems to make LLVM actually work without Bus Error on 32bit
sparc.

Differential Revision: http://reviews.llvm.org/D10271

llvm-svn: 239872
2015-06-17 01:21:20 +00:00
Rafael Espindola
ac851b9af7 Use std::unique_ptr to manage the DataStreamer in bitcode parsing.
We were already deleting it, this just makes it explicit.

llvm-svn: 239867
2015-06-16 23:29:49 +00:00
Rafael Espindola
5c0ce7ad5b Rename and improve emitSectionOffset.
Different object formats represent references from dwarf in different ways.

ELF uses a relocation to the referenced point (except for .dwo) and
COFF/MachO use the offset of the referenced point inside its section.

This patch renames emitSectionOffset because

* It doesn't produce an offset on ELF.
* It changes behavior depending on how DWARF is represented, so adding
dwarf to its name is probably a good thing.

The patch also adds an option to force the use of offsets.That avoids
funny looking code like

  if (!UseOffsets)
    Asm->emitSectionOffset....

It was correct, but read as if the ! was inverted.

llvm-svn: 239866
2015-06-16 23:22:02 +00:00
Tyler Nowicki
a672c833b7 Refactor RecurrenceInstDesc
Moved RecurrenceInstDesc into RecurrenceDescriptor to simplify the namespaces.

llvm-svn: 239862
2015-06-16 22:59:45 +00:00
Rafael Espindola
980b007510 Return a unique_ptr from getLazyBitcodeModule and parseBitcodeFile. NFC.
llvm-svn: 239858
2015-06-16 22:27:55 +00:00
Philip Reames
fc6ddd62bf Reapply 239795 - [InstCombine] Propagate non-null facts to call parameters
The original change broke clang side tests.  I will be submitting those momentarily.  This change includes post commit feedback on the original change from from Pete Cooper.

Original Submission comments:
If a parameter to a function is known non-null, use the existing parameter attributes to record that fact at the call site. This has no optimization benefit by itself - that I know of - but is an enabling change for http://reviews.llvm.org/D9129.

Differential Revision: http://reviews.llvm.org/D9132

llvm-svn: 239849
2015-06-16 20:24:25 +00:00
Diego Novillo
8e90e86295 Fix PR 23525 - Separate header mass propagation in irregular loops.
Summary:
When propagating mass through irregular loops, the mass flowing through
each loop header may not be equal. This was causing wrong frequencies
to be computed for irregular loop headers.

Fixed by keeping track of masses flowing through each of the headers in
an irregular loop. To do this, we now keep track of per-header backedge
weights. After the loop mass is distributed through the loop, the
backedge weights are used to re-distribute the loop mass to the loop
headers.

Since each backedge will have a mass proportional to the different
branch weights, the loop headers will end up with a more approximate
weight distribution (as opposed to the current distribution that assumes
that every loop header is the same).

Reviewers: dexonsmith

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10348

llvm-svn: 239843
2015-06-16 19:10:58 +00:00
Matthias Braun
c47ad67935 TargetRegisterInfo: Make the concept of imprecise lane masks explicit
LaneMasks as given by getSubRegIndexLaneMask() have a limited number of
of bits, so for targets with more than 31 disjunct subregister there may
be cases where:

   getSubReg(Reg,A) does not overlap getSubReg(Reg,B)

but we still have

   (getSubRegIndexLaneMask(A) & getSubRegIndexLaneMask(B)) != 0.

I had hoped to keep this an implementation detail of the tablegen but as
my next commit shows we can avoid unnecessary imp-defs operands if we
know that the lane masks in use are precise.

This is in preparation to http://reviews.llvm.org/D10470.

llvm-svn: 239837
2015-06-16 18:22:26 +00:00
Tyler Nowicki
0f2cf63b01 Rename Reduction variables/structures to Recurrence.
A reduction is a special kind of recurrence. In the loop vectorizer we currently
identify basic reductions. Future patches will extend this to identifying basic
recurrences.

llvm-svn: 239835
2015-06-16 18:07:34 +00:00
Sanjay Patel
ace9860241 propagate IR-level fast-math-flags to DAG nodes, disabled by default
This is an updated version of the patch that was checked in at:
http://reviews.llvm.org/rL237046

but subsequently reverted because it exposed a bug in the DAG Combiner:
http://reviews.llvm.org/D9893

This time, there's an enablement flag ("EnableFMFInDAG") around the code in
SelectionDAGBuilder where we copy the set of FP optimization flags from IR
instructions to DAG nodes. So, in theory, there should be no functional change
from this patch as-is, but it will allow testing with the added functionality
to proceed via "-enable-fmf-dag" passed to llc.

This patch adds the minimum plumbing necessary to use IR-level
fast-math-flags (FMF) in the backend without actually using
them for anything yet. This is a follow-on to:
http://reviews.llvm.org/rL235997

Differential Revision: http://reviews.llvm.org/D10403

llvm-svn: 239828
2015-06-16 16:25:43 +00:00
Daniel Sanders
df4e26d91a Replace string GNU Triples with llvm::Triple in TargetMachine::getTargetTriple(). NFC.
Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10381

llvm-svn: 239815
2015-06-16 13:15:50 +00:00
Daniel Sanders
4f36d138c9 Recommit r239721: Replace string GNU Triples with llvm::Triple in InitMCObjectFileInfo. NFC.
Summary:
This affects other tools so the previous C++ API has been retained as a
deprecated function for the moment. Clang has been updated with a trivial
patch (not covered by the pre-commit review) to avoid breaking -Werror builds.
Other in-tree tools will be fixed with similar patches.

This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

The first time this was committed it accidentally fixed an inconsistency in
triples in llvm-mc and this caused a failure. This inconsistency was fixed in
r239808.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10366

llvm-svn: 239812
2015-06-16 12:18:07 +00:00
Asaf Badouh
9879449284 [AVX512] add integer min/max intrinsics support.
review:
http://reviews.llvm.org/D10439

llvm-svn: 239806
2015-06-16 08:39:27 +00:00
Craig Topper
b603d53f5d [TableGen] Remove unused method declaration. NFC
llvm-svn: 239801
2015-06-16 05:44:06 +00:00
Philip Reames
2aad4769d2 Revert 239795
I forgot to update some clang test cases.  I'll fix and resubmit tomorrow.

llvm-svn: 239800
2015-06-16 01:20:53 +00:00
Philip Reames
54716a6f5b [InstCombine] Propagate non-null facts to call parameters
If a parameter to a function is known non-null, use the existing parameter attributes to record that fact at the call site. This has no optimization benefit by itself - that I know of - but is an enabling change for http://reviews.llvm.org/D9129.

Differential Revision: http://reviews.llvm.org/D9132

llvm-svn: 239795
2015-06-16 00:43:54 +00:00
Duncan P. N. Exon Smith
df64c4d514 modules: Mark CodeGen/DIEValues.def as a textual inclusion
Mark CodeGen/DIEValues.def as a textual inclusion to fix the
`LLVM_ENABLE_MODULES` build.

llvm-svn: 239794
2015-06-16 00:43:52 +00:00
Alex Lorenz
0686df9bd6 MIR Serialization: Print and parse simple machine function attributes.
This commit serializes the simple, scalar attributes from the 
'MachineFunction' class.

Reviewers: Duncan P. N. Exon Smith

Differential Revision: http://reviews.llvm.org/D10449

llvm-svn: 239790
2015-06-16 00:10:47 +00:00
Adrian Prantl
5862854484 Debug Info IR: Switch DIObjCProperty to use DITypeRef.
This is a prerequisite for turning on ODR type uniquing for ObjC++.

rdar://problem/21377883

llvm-svn: 239780
2015-06-15 23:18:03 +00:00
Peter Collingbourne
cb037f41a1 Add safestack attribute to LLVMAttribute enum and Go bindings. Correct
constants in commented-out part of LLVMAttribute enum. Add tests that verify
that the safestack attribute is only allowed as a function attribute.

llvm-svn: 239772
2015-06-15 22:16:51 +00:00
Peter Collingbourne
ea9bf98c05 Protection against stack-based memory corruption errors using SafeStack
This patch adds the safe stack instrumentation pass to LLVM, which separates
the program stack into a safe stack, which stores return addresses, register
spills, and local variables that are statically verified to be accessed
in a safe way, and the unsafe stack, which stores everything else. Such
separation makes it much harder for an attacker to corrupt objects on the
safe stack, including function pointers stored in spilled registers and
return addresses. You can find more information about the safe stack, as
well as other parts of or control-flow hijack protection technique in our
OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
and our project website (http://levee.epfl.ch).

The overhead of our implementation of the safe stack is very close to zero
(0.01% on the Phoronix benchmarks). This is lower than the overhead of
stack cookies, which are supported by LLVM and are commonly used today,
yet the security guarantees of the safe stack are strictly stronger than
stack cookies. In some cases, the safe stack improves performance due to
better cache locality.

Our current implementation of the safe stack is stable and robust, we
used it to recompile multiple projects on Linux including Chromium, and
we also recompiled the entire FreeBSD user-space system and more than 100
packages. We ran unit tests on the FreeBSD system and many of the packages
and observed no errors caused by the safe stack. The safe stack is also fully
binary compatible with non-instrumented code and can be applied to parts of
a program selectively.

This patch is our implementation of the safe stack on top of LLVM. The
patches make the following changes:

- Add the safestack function attribute, similar to the ssp, sspstrong and
  sspreq attributes.

- Add the SafeStack instrumentation pass that applies the safe stack to all
  functions that have the safestack attribute. This pass moves all unsafe local
  variables to the unsafe stack with a separate stack pointer, whereas all
  safe variables remain on the regular stack that is managed by LLVM as usual.

- Invoke the pass as the last stage before code generation (at the same time
  the existing cookie-based stack protector pass is invoked).

- Add unit tests for the safe stack.

Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.

Differential Revision: http://reviews.llvm.org/D6094

llvm-svn: 239761
2015-06-15 21:07:11 +00:00
Alex Lorenz
2e08d769c3 MIR Serialization: Connect the machine function analysis pass to the MIR parser.
This commit connects the machine function analysis pass (which creates machine
functions) to the MIR parser, which will initialize the machine functions 
with the state from the MIR file and reconstruct the machine IR.

This commit introduces a new interface called 'MachineFunctionInitializer',
which can be used to provide custom initialization for the machine functions.

This commit also introduces a new diagnostic class called 
'DiagnosticInfoMIRParser' which is used for MIR parsing errors.
This commit modifies the default diagnostic handling in LLVMContext - now the
the diagnostics are printed directly into llvm::errs() so that the MIR parsing 
errors can be printed with colours.  

Reviewers: Justin Bogner

Differential Revision: http://reviews.llvm.org/D9928

llvm-svn: 239753
2015-06-15 20:30:22 +00:00
Sanjoy Das
a95063f8bb Unbreak the build from r239740.
Do not re-use an enum name as a field name.  Some bots don't like this.

llvm-svn: 239746
2015-06-15 19:29:44 +00:00
Sanjoy Das
cc16b02fd5 [CodeGen] Add a pass to fold null checks into nearby memory operations.
Summary:
This change adds an "ImplicitNullChecks" target dependent pass.  This
pass folds null checks into memory operation using the FAULTING_LOAD
pseudo-op introduced in previous patches.

Depends on D10197
Depends on D10199
Depends on D10200

Reviewers: reames, rnk, pgavlin, JosephTremoulet, atrick

Reviewed By: atrick

Subscribers: ab, JosephTremoulet, llvm-commits

Differential Revision: http://reviews.llvm.org/D10201

llvm-svn: 239743
2015-06-15 18:44:27 +00:00
Sanjoy Das
f1dab90647 [TargetInstrInfo] Add new hook: AnalyzeBranchPredicate.
Summary:
NFC: no one uses AnalyzeBranchPredicate yet.

Add TargetInstrInfo::AnalyzeBranchPredicate and implement for x86.  A
later change adding support for page-fault based implicit null checks
depends on this.

Reviewers: reames, ab, atrick

Reviewed By: atrick

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10200

llvm-svn: 239742
2015-06-15 18:44:21 +00:00
Sanjoy Das
ce0590cf7a [TargetInstrInfo] Rename getLdStBaseRegImmOfs and implement for x86.
Summary:

TargetInstrInfo::getLdStBaseRegImmOfs to
TargetInstrInfo::getMemOpBaseRegImmOfs and implement for x86.  The
implementation only handles a few easy cases now and will be made more
sophisticated in the future.

This is NFCI: the only user of `getLdStBaseRegImmOfs` (now
`getmemOpBaseRegImmOfs`) is `LoadClusterMotion` and `LoadClusterMotion`
is disabled for x86.

Reviewers: reames, ab, MatzeB, atrick

Reviewed By: MatzeB, atrick

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10199

llvm-svn: 239741
2015-06-15 18:44:14 +00:00
Sanjoy Das
b396b9e375 [CodeGen] Introduce a FAULTING_LOAD_OP pseudo-op.
Summary:
This instruction encodes a loading operation that may fault, and a label
to branch to if the load page-faults.  The locations of potentially
faulting loads and their "handler" destinations are recorded in a
FaultMap section, meant to be consumed by LLVM's clients.

Nothing generates FAULTING_LOAD_OP instructions yet, but they will be
used in a future change.

The documentation (FaultMaps.rst) needs improvement and I will update
this diff with a more expanded version shortly.

Depends on D10196

Reviewers: rnk, reames, AndyAyers, ab, atrick, pgavlin

Reviewed By: atrick, pgavlin

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10197

llvm-svn: 239740
2015-06-15 18:44:08 +00:00
Rafael Espindola
22f581acc4 Avoid a "always true" warning from gcc.
llvm-svn: 239729
2015-06-15 14:49:41 +00:00
Daniel Sanders
52648be0df Revert r239721 - Replace string GNU Triples with llvm::Triple in InitMCObjectFileInfo. NFC.
It appears to cause sparc-little-endian.s to assert on Windows and Darwin.

llvm-svn: 239724
2015-06-15 10:34:38 +00:00
Daniel Sanders
15d01ae3f0 Replace string GNU Triples with llvm::Triple in InitMCObjectFileInfo. NFC.
Summary:
This affects other tools so the previous C++ API has been retained as a
deprecated function for the moment. Clang has been updated with a trivial
patch (not covered by the pre-commit review) to avoid breaking -Werror builds.
Other in-tree tools will be fixed with similar trivial patches.

This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rengolin

Reviewed By: rengolin

Subscribers: llvm-commits, rengolin

Differential Revision: http://reviews.llvm.org/D10366

llvm-svn: 239721
2015-06-15 09:19:41 +00:00
Rui Ueyama
04b2667fd9 [Support][Endian] Define |= and &= for u{big,little}{16,32,64}_t.
llvm-svn: 239716
2015-06-15 03:00:15 +00:00
Igor Breger
f163333815 AVX-512: Implemented cvtsi2ss/d cvtusi2ss/d instructions with round control for KNL.
Added intrinsics for cvtsi2ss/d instructions.
Added tests for intrinsics and encoding.

Differential Revision: http://reviews.llvm.org/D10430

llvm-svn: 239694
2015-06-14 12:44:55 +00:00
Benjamin Kramer
3dd5c1fd9a [ExecutionEngine] ArrayRefize argument passing.
No functionality change intended.

llvm-svn: 239687
2015-06-13 19:50:29 +00:00
Rafael Espindola
3e9c3a2ef1 Bring in a BumpPtrStringSaver from lld and simplify the interface.
StringSaver now always saves to a BumpPtrAllocator.

The only reason for having the virtual saveImpl is so lld can have a
thread safe version.

The reason for the distinct BumpPtrStringSaver class is to avoid the
virtual destructor.

llvm-svn: 239669
2015-06-13 12:49:52 +00:00
Matthias Braun
729d1d707d Rename TargetSubtargetInfo::enablePostMachineScheduler() to enablePostRAScheduler()
r213101 changed the behaviour of this method to not only affect the
PostMachineScheduler scheduler but also the PostRAScheduler scheduler,
renaming should make this fact clear. Also document that the preferred
way is to specify this in the scheduling model instead of overriding
this method.

Differential Revision: http://reviews.llvm.org/D10427

llvm-svn: 239659
2015-06-13 03:42:16 +00:00
Matthias Braun
e311841a60 MachineLICM: Use TargetSchedModel instead of just itineraries
This will use Itinieraries if available, but will also work if just a
MCSchedModel is available.

Differential Revision: http://reviews.llvm.org/D10428

llvm-svn: 239658
2015-06-13 03:42:11 +00:00
Lang Hames
b65a8d97e2 [Orc] Tidy up the CompileOnDemand layer based on commit review from dblaikie.
NFC.

llvm-svn: 239642
2015-06-12 22:22:50 +00:00
Lang Hames
920fcbb99b [Orc] Fix a bug in the CompileOnDemand layer where stub decls were not cloned
into partitions. Also, add an option to clone stub definitions (not just decls)
into partitions: these definitions could be inlined in some places to avoid the
overhead of calling via the stub.

Found by inspection - no test case yet, although I plan to add a unit test for
this once the CompileOnDemand layer refactoring settles down.

llvm-svn: 239640
2015-06-12 21:31:15 +00:00
Douglas Katzman
be1678072c Add 'shave' processor name to Triple
Based on ArchType, Clang's driver can select a non-Clang compiler.
String parsing in Clang would have sufficed if it were only that,
however this change anticipates true llvm support.

Differential Revision: http://reviews.llvm.org/D10413

llvm-svn: 239631
2015-06-12 18:31:38 +00:00
Pete Cooper
de09767442 Remove unnecessary MCExpr.h include from MCSymbol.h
MCSymbol.h already forwards declares MCExpr and only uses MCExpr* so doesn't
need to include the header.

llvm-svn: 239626
2015-06-12 18:07:34 +00:00
Pete Cooper
2d7cfed081 Remove a bunch of inline keywords from User. NFC.
This came up in the patch review for http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20150608/281362.html.

llvm-svn: 239624
2015-06-12 17:48:21 +00:00
Pete Cooper
a9c553dd18 Move OperandList to be allocated prior to User for hung off subclasses.
For hung off uses, we need a Use* to tell use where the operands are.
This was User::OperandList but we want to remove that to save space
of all subclasses which aren't making use of 'hung off uses'.

Hung off uses now allocate their own 'OperandList' Use* in the
User::new which they call.

getOperandList() now uses the hung off uses bit to work out where the
Use* for the OperandList lives.  If a User has hung off uses, then this
bit tells them to go back a single Use* from the User* and use that
value as the OperandList.

If a User has no hung off uses, then we get the first operand by
subtracting (NumOperands * sizeof(Use)) from the User this pointer.

This saves a pointer from User and all subclasses.  Given the average
size of a subclass of User is 112 or 128 bytes, this saves around 7% of space
With malloc tending to align to 16-bytes the real saving is typically more like 3.5%.

On 'opt -O2 verify-uselistorder.lto.bc', peak memory usage prior to this change
is 149MB and after is 143MB so the savings are around 2.5% of peak.

Looking at some passes which allocate many Instructions and Values, parseIR drops
from 54.25MB to 52.21MB while the Inliner calls to Instruction::clone() drops
from 28.20MB to 27.05MB.

Reviewed by Duncan Exon Smith.

llvm-svn: 239623
2015-06-12 17:48:18 +00:00
Pete Cooper
fe53a1ccb4 Added a version of User::new for hung off uses.
There are now 2 versions of User::new.  The first takes a size_t and is the current
implementation for subclasses which need 0 or more Use's allocated for their operands.

The new version takes no extra arguments to say that this subclass needs 'hung off uses'.
The HungOffUses bool is now set in this version of User::new and we can assert in
allocHungOffUses that we are allowed to have hung off uses.
This ensures we call the correct version of User::new for subclasses which need hung off uses.

A future commit will then allocate space for a single Use* which will be used
in place of User::OperandList once that field has been removed.

Reviewed by Duncan Exon Smith.

llvm-svn: 239622
2015-06-12 17:48:14 +00:00
Pete Cooper
eeab7b6f62 Rename NumOperands to make it clear its managed by the User. NFC.
This is to try make it very clear that subclasses shouldn't be changing
the value directly.  Now that OperandList for normal instructions is computed
using the NumOperands, its critical that the NumOperands is accurate or we
could compute the wrong offset to the first operand.

I looked over all places which update NumOperands and they are all safe.
Hung off use User's don't use NumOperands to compute the OperandList so they
are safe to continue to manipulate it.  The only other User which changed it
was GlobalVariable which has an optional init list but always allocated space
for a single Use.  It was correctly setting NumOperands to 1 before setting an
initializer, and setting it to 0 after clearing the init list, so the order was safe.

Added some comments to that code to make sure that this isn't changed in future
without being aware of this constraint.

Reviewed by Duncan Exon Smith.

llvm-svn: 239621
2015-06-12 17:48:10 +00:00