Commit Graph

241 Commits

Author SHA1 Message Date
Teresa Johnson 1493ad9c24 Fix PR25101 - Handle anonymous functions without VST entries
Summary:
The change to use the VST function entries for lazy deserialization did
not handle the case of anonymous functions without aliases. In that case
we must fall back to scanning the function blocks as there is no VST
entry.

Reviewers: dexonsmith, joker.eph, davidxl

Subscribers: tstellarAMD, llvm-commits

Differential Revision: http://reviews.llvm.org/D13596

llvm-svn: 249947
2015-10-10 14:18:36 +00:00
Filipe Cabecinhas b70fd8719e Make sure the CastInst is valid before trying to create it
Bug found with afl-fuzz.

llvm-svn: 249396
2015-10-06 12:37:54 +00:00
Teresa Johnson 403a787e03 Support for function summary index bitcode sections and files.
Summary:
The bitcode format is described in this document:
  https://drive.google.com/file/d/0B036uwnWM6RWdnBLakxmeDdOeXc/view
For more info on ThinLTO see:
  https://sites.google.com/site/llvmthinlto

The first customer is ThinLTO, however the data structures are designed
and named more generally based on prior feedback. There are a few
comments regarding how certain interfaces are used by ThinLTO, and the
options added here to gold currently have ThinLTO-specific names as the
behavior they provoke is currently ThinLTO-specific.

This patch includes support for generating per-module function indexes,
the combined index file via the gold plugin, and several tests
(more are included with the associated clang patch D11908).

Reviewers: dexonsmith, davidxl, joker.eph

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13107

llvm-svn: 249270
2015-10-04 14:33:43 +00:00
Sanjoy Das b513a9fa4f [Bitcode][Asm] Teach LLVM to read and write operand bundles.
Summary:
This also adds the first set of tests for operand bundles.

The optimizer has not been audited to ensure that it does the right
thing with operand bundles.

Depends on D12456.

Reviewers: reames, chandlerc, majnemer, dexonsmith, kmod, JosephTremoulet, rnk, bogner

Subscribers: maksfb, llvm-commits

Differential Revision: http://reviews.llvm.org/D12457

llvm-svn: 248551
2015-09-24 23:34:52 +00:00
Teresa Johnson ff642b9b84 Restore "Function bitcode index in Value Symbol Table and lazy reading support"
This reverts commit r247898 (which reverted r247894).

Patch fixed to address two issues exposed by buildbots:
- unused variable warning in NDEBUG mode
- std::initializer_list lifetime issue causing test failures

Original Summary:
Support for including the function bitcode indices in the Value Symbol
Table. This requires writing the VST after the function blocks, which in
turn requires a new VST forward declaration record encoding the offset of
the full VST (which is backpatched to contain the offset after the VST
is written).

This patch also enables the lazy function reader to use the new function
indices out of the VST. This support will be used by ThinLTO as well, which
will be in a follow on patch. Backwards compatibility with older bitcode
files is maintained.

A new test is also included.

The bitcode format (used for the lazy reader as well as the upcoming
ThinLTO patches) came out of discussions with Duncan and others and is
described here:
https://drive.google.com/file/d/0B036uwnWM6RWdnBLakxmeDdOeXc/view

Reviewers: dexonsmith, davidxl, joker.eph

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12536

llvm-svn: 247927
2015-09-17 20:12:00 +00:00
Teresa Johnson 2e98d57ad4 Revert "Function bitcode index in Value Symbol Table and lazy reading support"
Temporarily revert to fix some buildbot issues. One is a minor issue
with a variable unused in NDEBUG mode. More concerning are some test
failures on win7 that I need to dig into.

This reverts commit 4e66a74543459832cfd571db42b4543580ae1d1d.

llvm-svn: 247898
2015-09-17 16:19:10 +00:00
Teresa Johnson b77b1f8a0c Function bitcode index in Value Symbol Table and lazy reading support
Summary:
Support for including the function bitcode indices in the Value Symbol
Table. This requires writing the VST after the function blocks, which in
turn requires a new VST forward declaration record encoding the offset of
the full VST (which is backpatched to contain the offset after the VST
is written).

This patch also enables the lazy function reader to use the new function
indices out of the VST. This support will be used by ThinLTO as well, which
will be in a follow on patch. Backwards compatibility with older bitcode
files is maintained.

A new test is also included.

The bitcode format (used for the lazy reader as well as the upcoming
ThinLTO patches) came out of discussions with Duncan and others and is
described here:
https://drive.google.com/file/d/0B036uwnWM6RWdnBLakxmeDdOeXc/view

Reviewers: dexonsmith, davidxl, joker.eph

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12536

llvm-svn: 247894
2015-09-17 15:52:30 +00:00
Reid Kleckner 5dbee7baef [IR] Print the label operands of a catchpad like an invoke
The rest of the EH pads are fine, since they have at most one label and
take fewer operands for the personality.

Old catchpad vs. new:
  %5 = catchpad [i8* bitcast (i32 ()* @"\01?filt$0@0@main@@" to i8*)] to label %__except.ret.10 unwind label %catchendblock.9
-----
  %5 = catchpad [i8* bitcast (i32 ()* @"\01?filt$0@0@main@@" to i8*)]
          to label %__except.ret.10 unwind label %catchendblock.9

llvm-svn: 247433
2015-09-11 17:27:52 +00:00
David Blaikie 2f40830dde [opaque pointer type] Add textual IR support for explicit type parameter for global aliases
update.py:
import fileinput
import sys
import re

alias_match_prefix = r"(.*(?:=|:|^)\s*(?:external |)(?:(?:private|internal|linkonce|linkonce_odr|weak|weak_odr|common|appending|extern_weak|available_externally) )?(?:default |hidden |protected )?(?:dllimport |dllexport )?(?:unnamed_addr |)(?:thread_local(?:\([a-z]*\))? )?alias"
plain = re.compile(alias_match_prefix + r" (.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|addrspacecast|\[\[[a-zA-Z]|\{\{).*$)")
cast  = re.compile(alias_match_prefix + r") ((?:bitcast|inttoptr|addrspacecast)\s*\(.* to (.*?)(| addrspace\(\d+\) *)\*\)\s*(?:;.*)?$)")
gep   = re.compile(alias_match_prefix + r") ((?:getelementptr)\s*(?:inbounds)?\s*\((?P<type>.*), (?P=type)(?:\s*addrspace\(\d+\)\s*)?\* .*\)\s*(?:;.*)?$)")

def conv(line):
  m = re.match(cast, line)
  if m:
    return m.group(1) + " " + m.group(3) + ", " + m.group(2)
  m = re.match(gep, line)
  if m:
    return m.group(1) + " " + m.group(3) + ", " + m.group(2)
  m = re.match(plain, line)
  if m:
    return m.group(1) + ", " + m.group(2) + m.group(3) + "*" + m.group(4) + "\n"
  return line

for line in sys.stdin:
  sys.stdout.write(conv(line))

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

llvm-svn: 247378
2015-09-11 03:22:04 +00:00
Vedant Kumar 1abc48ee58 [Bitcode] Add xfail test for PR24755 (uselistorder)
This test stresses verify-uselistorder. PR24755 is caused by our
ignoring uses when they occur in the function personality slot, the
prologue data slot, or the prefix data slot.

llvm-svn: 247292
2015-09-10 16:02:24 +00:00
Vedant Kumar 9ebd49a4cf [Bitcode] Add compatibility tests for new instructions
Adds basic compatibility tests for the following instructions:

  catchpad, catchendpad, cleanuppad, cleanupendpad, terminatepad,
  cleanupret, catchret

llvm-svn: 247087
2015-09-08 22:33:23 +00:00
Vedant Kumar 52cd4eecac [Bitcode] Add compatibility test for llvm 3.7.0
This patch adds llvm-3.7 IR and generated bitcode for our compatibility
test (in accordance with the developer policy).

llvm-svn: 247031
2015-09-08 17:39:21 +00:00
Filipe Cabecinhas 984fefdd81 [BitcodeReader] Ensure we can read constant vector selects with an i1 condition
Summary:
Constant vectors weren't allowed to have an i1 condition in the
BitcodeReader. Make sure we have the same restrictions that are
documented, not more.

Reviewers: nlewycky, rafael, kschimpf

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12440

llvm-svn: 246459
2015-08-31 18:00:30 +00:00
Duncan P. N. Exon Smith 814b8e91c7 DI: Require subprogram definitions to be distinct
As a follow-up to r246098, require `DISubprogram` definitions
(`isDefinition: true`) to be 'distinct'.  Specifically, add an assembler
check, a verifier check, and bitcode upgrading logic to combat testcase
bitrot after the `DIBuilder` change.

While working on the testcases, I realized that
test/Linker/subprogram-linkonce-weak-odr.ll isn't relevant anymore.  Its
purpose was to check for a corner case in PR22792 where two subprogram
definitions match exactly and share the same metadata node.  The new
verifier check, requiring that subprogram definitions are 'distinct',
precludes that possibility.

I updated almost all the IR with the following script:

    git grep -l -E -e '= !DISubprogram\(.* isDefinition: true' |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's/= \(!DISubprogram(.*, isDefinition: true\)/= distinct \1/'

Likely some variant of would work for out-of-tree testcases.

llvm-svn: 246327
2015-08-28 20:26:49 +00:00
Vedant Kumar 06f0678010 [test] Testing write access to llvm
llvm-svn: 245074
2015-08-14 17:42:50 +00:00
David Majnemer b611e3f50e [IR] Add token types
This introduces the basic functionality to support "token types".
The motivation stems from the need to perform operations on a Value
whose provenance cannot be obscured.

There are several applications for such a type but my immediate
motivation stems from WinEH.  Our personality routine enforces a
single-entry - single-exit regime for cleanups.  After several rounds of
optimizations, we may be left with a terminator whose "cleanup-entry
block" is not entirely clear because control flow has merged two
cleanups together.  We have experimented with using labels as operands
inside of instructions which are not terminators to indicate where we
came from but found that LLVM does not expect such exotic uses of
BasicBlocks.

Instead, we can use this new type to clearly associate the "entry point"
and "exit point" of our cleanup.  This is done by having the cleanuppad
yield a Token and consuming it at the cleanupret.
The token type makes it impossible to obscure or otherwise hide the
Value, making it trivial to track the relationship between the two
points.

What is the burden to the optimizer?  Well, it turns out we have already
paid down this cost by accepting that there are certain calls that we
are not permitted to duplicate, optimizations have to watch out for
such instructions anyway.  There are additional places in the optimizer
that we will probably have to update but early examination has given me
the impression that this will not be heroic.

Differential Revision: http://reviews.llvm.org/D11861

llvm-svn: 245029
2015-08-14 05:09:07 +00:00
Igor Laevsky 30143aee11 Emit argmemonly attribute for intrinsics.
Differential Revision: http://reviews.llvm.org/D11352

llvm-svn: 244920
2015-08-13 17:40:04 +00:00
Sean Silva c2b70bf999 [compatibility.ll] Cover explicitly named comdats.
Patch by Vedant Kumar! <vsk@apple.com>

llvm-svn: 244284
2015-08-06 22:04:21 +00:00
Derek Schuff b4c1c28c6e Fix testing for end of stream in bitstream reader.
This fixes a bug found while working on the bitcode reader. In
particular, the method BitstreamReader::AtEndOfStream doesn't always
behave correctly when processing a data streamer. The method
fillCurWord doesn't properly set CurWord/BitsInCurWord if the data
streamer was already at eof, but GetBytes had not yet set the
ObjectSize field of the streaming memory object.

This patch fixes this problem, and provides a test to show that
this problem has been fixed.

Patch by Karl Schimpf.

Differential Revision: http://reviews.llvm.org/D11391

llvm-svn: 243890
2015-08-03 18:01:50 +00:00
Duncan P. N. Exon Smith 55ca964e94 DI: Disallow uniquable DICompileUnits
Since r241097, `DIBuilder` has only created distinct `DICompileUnit`s.
The backend is liable to start relying on that (if it hasn't already),
so make uniquable `DICompileUnit`s illegal and automatically upgrade old
bitcode.  This is a nice cleanup, since we can remove an unnecessary
`DenseSet` (and the associated uniquing info) from `LLVMContextImpl`.

Almost all the testcases were updated with this script:

    git grep -e '= !DICompileUnit' -l -- test |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's,= !DICompileUnit,= distinct !DICompileUnit,'

I imagine something similar should work for out-of-tree testcases.

llvm-svn: 243885
2015-08-03 17:26:41 +00:00
Artur Pilipenko 17376c4e02 Currently string attributes on function arguments/return values can be generated using LLVM API. However they are not supported in parser. So, the following scenario will fail:
* generate function with string attribute using API,
* dump it in LL format,
* try to parse.
Add parser support for string attributes to fix the issue.

Reviewed By: reames, hfinkel

Differential Revision: http://reviews.llvm.org/D11058

llvm-svn: 243877
2015-08-03 14:31:49 +00:00
Duncan P. N. Exon Smith 375fa1381d IR: Add a broad bitcode compatibility test
Successive versions of LLVM should retain the ability to parse bitcode
generated by old releases of the compiler.  This adds a bitcode format
compatibility test, which is intended to provide good (albeit not
entirely exhaustive) coverage of the current LangRef.

This also includes compatibility tests for LLVM 3.6.  After every 3.X.0
release, the compatibility.ll file from the 3.X branch should be copied
to compatibility-3.X.ll on trunk, and the 3.X.0 release used to generate
a corresponding bitcode file.

Patch by Vedant Kumar!

llvm-svn: 243779
2015-07-31 20:44:32 +00:00
Duncan P. N. Exon Smith ed013cd221 DI: Remove DW_TAG_arg_variable and DW_TAG_auto_variable
Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags,
using `DW_TAG_variable` in their place Stop exposing the `tag:` field at
all in the assembly format for `DILocalVariable`.

Most of the testcase updates were generated by the following sed script:

    find test/ -name "*.ll" -o -name "*.mir" |
    xargs grep -l 'DILocalVariable' |
    xargs sed -i '' \
      -e 's/tag: DW_TAG_arg_variable, //' \
      -e 's/tag: DW_TAG_auto_variable, //'

There were only a handful of tests in `test/Assembly` that I needed to
update by hand.

(Note: a follow-up could change `DILocalVariable::DILocalVariable()` to
set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable`
(as appropriate), instead of having that logic magically in the backend
in `DbgVariable`.  I've added a FIXME to that effect.)

llvm-svn: 243774
2015-07-31 18:58:39 +00:00
Igor Laevsky 39d662f7ba Add argmemonly attribute.
This change adds new attribute called "argmemonly". Function marked with this attribute can only access memory through it's argument pointers. This attribute directly corresponds to the "OnlyAccessesArgumentPointees" ModRef behaviour in alias analysis.

Differential Revision: http://reviews.llvm.org/D10398

llvm-svn: 241979
2015-07-11 10:30:36 +00:00
James Molloy 88eb535b2d Add support for fast-math flags to the FCmp instruction.
FCmp behaves a lot like a floating-point binary operator in many ways,
and can benefit from fast-math information. Flags such as nsz and nnan
can affect if this fcmp (in combination with a select) can be treated
as a fminnum/fmaxnum operation.

This adds backwards-compatible bitcode support, IR parsing and writing,
LangRef changes and IRBuilder changes. I'll need to audit InstSimplify
and InstCombine in a followup to find places where flags should be
copied.

llvm-svn: 241901
2015-07-10 12:52:00 +00:00
Rafael Espindola 4e7212177f Fix for PR23310: llvm-dis crashes when trying to upgrade an intrinsic.
When trying to upgrade @llvm.x86.sse2.psrl.dq while parsing a module,
BitcodeReader adds the function to its worklist twice, resulting in a
crash when accessing it the second time.

This patch replaces the worklist vector by a map.

Patch by Philip Pfaffe.

llvm-svn: 241281
2015-07-02 16:22:40 +00:00
David Majnemer 7fddeccb8b Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00
Rafael Espindola c6afe0d4e9 Improve handling of end of file in the bitcode reader.
Before this patch the bitcode reader would read a module from a file
that contained in order:

* Any number of non MODULE_BLOCK sub blocks.
* One MODULE_BLOCK
* Any number of non MODULE_BLOCK sub blocks.
* 4 '\n' characters to handle OS X's ranlib.

Since we support lazy reading of modules, any information that is relevant
for the module has to be in the MODULE_BLOCK or before it. We don't gain
anything from checking what is after.

This patch then changes the reader to stop once the MODULE_BLOCK has been
successfully parsed.

This avoids the ugly special case for .bc files in an archive and makes it
easier to embed bitcode files.

llvm-svn: 239845
2015-06-16 20:03:39 +00:00
Rafael Espindola 35f6faed67 Add a test for padded bitcode files.
llvm-svn: 239829
2015-06-16 16:36:15 +00:00
Filipe Cabecinhas da86b6d409 [BitcodeReader] Diagnose type mismatches with aliases
Bug found with AFL fuzz.

llvm-svn: 238895
2015-06-03 01:30:13 +00:00
Filipe Cabecinhas 7b3995885d [Bitcode] Minimize the test to not conflict with others
Source for the test:
@bloom = global <3 x i32> <i32 0, i32 1, i32 42>

Plus bit twiddling to set the vector numelts to 0 (in the bc file).

llvm-svn: 238894
2015-06-03 01:30:08 +00:00
Filipe Cabecinhas 8e42190d20 [BitcodeReader] Check vector size before trying to create a VectorType
Bug found with AFL fuzz

llvm-svn: 238891
2015-06-03 00:05:30 +00:00
Filipe Cabecinhas 14e686774d [BitcodeReader] Change an assert to a call to a call to Error()
It's reachable from user input.

Bug found with AFL fuzz.

llvm-svn: 238633
2015-05-30 00:17:20 +00:00
Filipe Cabecinhas 6a92a3fe34 [BitcodeReader] Change assert to report_fatal_error
It can be triggered by user input.

Bug found with AFL fuzz.

llvm-svn: 238272
2015-05-27 01:05:40 +00:00
Filipe Cabecinhas 8cd99e9a5a [BitstreamReader] Make sure the Array operand type is an encoding
Bug found with AFL fuzz.

llvm-svn: 238269
2015-05-27 00:48:43 +00:00
Filipe Cabecinhas bc6a909384 [BitcodeReader] Make sure abbrev records have at least one operand (record code)
Bug found with AFL fuzz.

llvm-svn: 238265
2015-05-26 23:52:21 +00:00
Owen Anderson 85fa7d5037 Add initial support for the convergent attribute.
llvm-svn: 238264
2015-05-26 23:48:40 +00:00
Filipe Cabecinhas 0eb8a59a67 [BitcodeReader] Sanity check on Comdat ID
Shouldn't be an assert, since user input can trigger it.

Bug found with AFL fuzz.

llvm-svn: 238261
2015-05-26 23:00:56 +00:00
Adrian Prantl 1f599f9f65 IR / debug info: Add a DWOId field to DICompileUnit,
so DWARF skeleton CUs can be expression in IR. A skeleton CU is a
(typically empty) DW_TAG_compile_unit that has a DW_AT_(GNU)_dwo_name and
a DW_AT_(GNU)_dwo_id attribute. It is used to refer to external debug info.

This is a prerequisite for clang module debugging as discussed in
http://lists.cs.uiuc.edu/pipermail/cfe-dev/2014-November/040076.html.
In order to refer to external types stored in split DWARF (dwo) objects,
such as clang modules, we need to emit skeleton CUs, which identify the
dwarf object (i.e., the clang module) by filename (the SplitDebugFilename)
and a hash value, the dwo_id.

This patch only contains the IR changes. The idea is that a CUs with a
non-zero dwo_id field will be emitted together with a DW_AT_GNU_dwo_name
and DW_AT_GNU_dwo_id attribute.

http://reviews.llvm.org/D9488
rdar://problem/20091852

llvm-svn: 237949
2015-05-21 20:37:30 +00:00
Filipe Cabecinhas fc93be21ea Change a reachable unreachable to a fatal error.
Summary:
Also tagged a FIXME comment, and added information about why it breaks.

Bug found using AFL fuzz.

Reviewers: rafael, craig.topper

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9729

llvm-svn: 237709
2015-05-19 18:18:10 +00:00
Filipe Cabecinhas 32af542194 [BitcodeReader] Error out if we read an invalid function argument type
Bug found with AFL fuzz.

llvm-svn: 237650
2015-05-19 01:21:06 +00:00
Filipe Cabecinhas f3fa99c48e [BitcodeReader] It's a malformed block if CodeLenWidth is too big
Bug found with AFL fuzz.

llvm-svn: 237646
2015-05-19 00:34:17 +00:00
Filipe Cabecinhas 4708a02a78 [BitcodeReader] Make sure the type of the inserted value matches the type of the aggregate at those indices
Bug found with AFL-fuzz.

llvm-svn: 237628
2015-05-18 22:27:11 +00:00
Filipe Cabecinhas 11bb8495f6 Extract the load/store type verification to a separate function.
Summary:
Added isLoadableOrStorableType to PointerType.

We were doing some checks in some places, occasionally assert()ing instead
of telling the caller. With this patch, I'm putting all type checking in
the same place for load/store type instructions, and verifying the same
thing every time.

I also added a check for load/store of a function type.

Applied extracted check to Load, Store, and Cmpxcg.

I don't have exhaustive tests for all of these, but all Error() calls in
TypeCheckLoadStoreInst are being tested (in invalid.test).

Reviewers: dblaikie, rafael

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9785

llvm-svn: 237619
2015-05-18 21:48:55 +00:00
Filipe Cabecinhas 1c299d05e6 [BitcodeReader] Don't allow INSERTVAL/EXTRACTVAL with 0 indices
This would trigger an assertion later.

Bug found with AFL fuzz.

llvm-svn: 237494
2015-05-16 00:33:12 +00:00
Duncan P. N. Exon Smith 538ef562bd Bitcode: Set LastDL after writing DebugLocs
Somehow I dropped this in r233585, and we haven't had `DEBUG_LOC_AGAIN`
records since.  Add it back.  Also tests that the output assembly looks
okay.

Fixes PR23436.

llvm-svn: 236661
2015-05-06 22:51:12 +00:00
Filipe Cabecinhas f8a16a952d Don't overflow GCTable
Summary: Bug found with AFL fuzz.

Reviewers: rafael, dexonsmith

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9361

llvm-svn: 236200
2015-04-30 04:09:41 +00:00
Filipe Cabecinhas 9a19e56306 Make sure Op->getType() is a PointerType before we cast<> it.
Bug found with AFL fuzz.

llvm-svn: 236193
2015-04-30 01:13:31 +00:00
Filipe Cabecinhas bad0779f63 Make sure we don't resize(0) when we get a fwdref with Idx == UINT_MAX
Make it an error instead.

Bug found with AFL fuzz.

llvm-svn: 236190
2015-04-30 00:52:42 +00:00
Filipe Cabecinhas d8a1bcd0ad Check that we have a valid PointerType element type before calling get()
Same as r236073 but for PointerType.

Bug found with AFL fuzz.

llvm-svn: 236079
2015-04-29 02:27:28 +00:00