Commit Graph

770 Commits

Author SHA1 Message Date
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Duncan P. N. Exon Smith 134cb5d30f BitcodeWriter: WorkList => Worklist, NFC
I have no idea how I chose two different spellings in the space of a
couple of weeks, but now I can't remember what to use where.  Choose
"Worklist".

llvm-svn: 266582
2016-04-18 01:24:58 +00:00
Mehdi Amini 2d28f7aa07 ThinLTO: Make aliases explicit in the summary
To be able to work accurately on the reference graph when taking
decision about internalizing, promoting, renaming, etc. We need
to have the alias information explicit.

Differential Revision: http://reviews.llvm.org/D18836

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266517
2016-04-16 06:56:44 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Mehdi Amini b5b289339b Revert "Make aliases explicit in the summary"
Inadvertently commited...

This reverts commit e618ec93786d99df2ddf280ad2d5e02f5516cecf.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266215
2016-04-13 17:20:07 +00:00
Mehdi Amini ce744a95fd Make aliases explicit in the summary
Summary:
To be able to work accurately on the reference graph when taking decision
about internalizing, promoting, renaming, etc. We need to have the alias
information explicit.

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18836

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266214
2016-04-13 17:18:42 +00:00
George Burgess IV 278199f615 Add the allocsize attribute to LLVM.
`allocsize` is a function attribute that allows users to request that
LLVM treat arbitrary functions as allocation functions.

This patch makes LLVM accept the `allocsize` attribute, and makes
`@llvm.objectsize` recognize said attribute.

The review for this was split into two patches for ease of reviewing:
D18974 and D14933. As promised on the revisions, I'm landing both
patches as a single commit.

Differential Revision: http://reviews.llvm.org/D14933

llvm-svn: 266032
2016-04-12 01:05:35 +00:00
Teresa Johnson 6f6fa36244 [ThinLTO] BitcodeWriter still requires Analysis library
This should fix bot failure:
http://bb.pgr.jp/builders/i686-mingw32-RA-on-linux/builds/9873

The bitcode writer unfortunately still needs the Analysis library, as it
replaces old dependence on BFI etc with dependence on new
ModuleSummaryAnalysis pass.

llvm-svn: 265945
2016-04-11 14:59:07 +00:00
Teresa Johnson 2d5487cf44 [ThinLTO] Move summary computation from BitcodeWriter to new pass
Summary:
This is the first step in also serializing the index out to LLVM
assembly.

The per-module summary written to bitcode is moved out of the bitcode
writer and to a new analysis pass (ModuleSummaryIndexWrapperPass).
The pass itself uses a new builder class to compute index, and the
builder class is used directly in places where we don't have a pass
manager (e.g. llvm-as).

Because we are computing summaries outside of the bitcode writer, we no
longer can use value ids created by the bitcode writer's
ValueEnumerator. This required changing the reference graph edge type
to use a new ValueInfo class holding a union between a GUID (combined
index) and Value* (permodule index). The Value* are converted to the
appropriate value ID during bitcode writing.

Also, this enables removal of the BitWriter library's dependence on the
Analysis library that was previously required for the summary computation.

Reviewers: joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18763

llvm-svn: 265941
2016-04-11 13:58:45 +00:00
Mehdi Amini f9e4576e08 Plumb the option to emit the `ModuleHash` in the bitcode through the bitcode writer APIs
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265907
2016-04-10 21:07:19 +00:00
Mehdi Amini 4a9a1816cb Rename parameter I to Index for WriteCombinedGlobalValueSummary() (NFC)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265729
2016-04-07 21:49:31 +00:00
Dmitry Polukhin a1feff7024 [GCC] Attribute ifunc support in llvm
This patch add support for GCC attribute((ifunc("resolver"))) for
targets that use ELF as object file format. In general ifunc is a
special kind of function alias with type @gnu_indirect_function. Patch
for Clang http://reviews.llvm.org/D15524

Differential Revision: http://reviews.llvm.org/D15525

llvm-svn: 265667
2016-04-07 12:32:19 +00:00
JF Bastien 800f87a871 NFC: make AtomicOrdering an enum class
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.

The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).

This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.

As a follow-up I'll add:
  bool operator<(AtomicOrdering, AtomicOrdering) = delete;
  bool operator>(AtomicOrdering, AtomicOrdering) = delete;
  bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
  bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.

Reviewers: jyknight, reames

Subscribers: jyknight, llvm-commits

Differential Revision: http://reviews.llvm.org/D18775

llvm-svn: 265602
2016-04-06 21:19:33 +00:00
Duncan P. N. Exon Smith 1de3c7e790 IR: Introduce ConstantAggregate, NFC
Add a common parent class for ConstantArray, ConstantVector, and
ConstantStruct called ConstantAggregate.  These are the aggregate
subclasses of Constant that take operands.

This is mainly a cleanup, adding common `isa` target and removing
duplicated code.  However, it also simplifies caching which constants
point transitively at `GlobalValue` (a possible future direction).

llvm-svn: 265466
2016-04-05 21:10:45 +00:00
Mehdi Amini 8958c40430 Rename FunctionIndex into GlobalValueIndex to reflect the recent changes (NFC)
The index used to contain only Function, but now contains GlobalValue
in general.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265230
2016-04-02 17:29:47 +00:00
Duncan P. N. Exon Smith 520f8542ff Bitcode: Try to emit metadata in function blocks
Whenever metadata is only referenced by a single function, emit the
metadata just in that function block.  This should improve lazy-loading
by reducing the amount of metadata in the global block.

For now, this should catch all DILocations, and anything else that
happens to be referenced only by a single function.

It's also a first step toward a couple of possible future directions
(which this commit does *not* implement):

 1. Some debug info metadata is only referenced from compile units and
    individual functions.  If we can drop the link from the compile
    unit, this optimization will get more powerful.

 2. Any uniqued metadata that isn't referenced globally can in theory be
    emitted in every function block that references it (trading off
    bitcode size and full-parse time vs. lazy-load time).

Note: this assumes the new BitcodeReader error checking from r265223.
The metadata stored in function blocks gets purged after parsing each
function, which means unresolved forward references will get lost.
Since all the global metadata should have already been resolved by the
time we get to the function metadata blocks we just need to check for
that case.  (If for some reason we need to handle bitcode that fails the
checks in r265223, the fix is to store about-to-be-dropped unresolved
nodes in MetadataList::shrinkTo until they can be handled succesfully by
a future call to MetadataList::tryToResolveCycles.)

llvm-svn: 265226
2016-04-02 15:22:57 +00:00
Duncan P. N. Exon Smith 0b76b723f4 Fix doxygen comments from r265224, NFC
llvm-svn: 265225
2016-04-02 15:16:56 +00:00
Duncan P. N. Exon Smith 9342911f31 BitcodeWriter: Further unify function metadata, NFC
Further unify the handling of function-local metadata with global
metadata, by exposing the same interface in ValueEnumerator.  Both
contexts use the same accessors:

  - getMDStrings(): get the strings for this block.
  - getNonMDStrings(): get the non-strings for this block.

A future commit will start adding strings to the function-block.

llvm-svn: 265224
2016-04-02 15:09:42 +00:00
Mehdi Amini 1e5fddda3d Reverts r265219.
Unintentionally commited... time to call the day off!

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265221
2016-04-02 05:35:03 +00:00
Mehdi Amini 5921a3ae66 wip
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265219
2016-04-02 05:34:14 +00:00
Mehdi Amini ad5741b075 Create a typedef GlobalValue::GUID for uint64_t and RAUW (NFC)
Summary: This should make the code more readable, especially all the map declarations.

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18721

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265215
2016-04-02 05:07:53 +00:00
Manman Ren 9bfd0d03e9 Swift Calling Convention: add swifterror attribute.
A ``swifterror`` attribute can be applied to a function parameter or an
AllocaInst.

This commit does not include any target-specific change. The target-specific
optimization will come as a follow-up patch.

Differential Revision: http://reviews.llvm.org/D18092

llvm-svn: 265189
2016-04-01 21:41:15 +00:00
Mehdi Amini d7ad221c16 Add a module Hash in the bitcode and the combined index, implementing a kind of "build-id"
This is intended to be used for ThinLTO incremental build.

Differential Revision: http://reviews.llvm.org/D18213

This is a recommit of r265095 after fixing the Windows issues.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265111
2016-04-01 05:33:11 +00:00
Mehdi Amini 85fb9e058e Revert "Add support for computing SHA1 in LLVM"
This reverts commit r265096, r265095, and r265094.
Windows build is broken, and the validation does not pass.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265102
2016-04-01 03:03:21 +00:00
Mehdi Amini 4c2ed3337d Add a module Hash in the bitcode and the combined index, implementing a kind of "build-id"
This is intended to be used for ThinLTO incremental build.

Differential Revision: http://reviews.llvm.org/D18213

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265095
2016-04-01 01:30:06 +00:00
Manman Ren f46262e0b7 Swift Calling Convention: add swiftself attribute.
Differential Revision: http://reviews.llvm.org/D17866

llvm-svn: 264754
2016-03-29 17:37:21 +00:00
Duncan P. N. Exon Smith 544e4f97b3 BitcodeWriter: Replace dead code with an assertion, NFC
The caller of ValueEnumerator::EnumerateOperandType never sends in
metadata.  Assert that, and remove the unnecessary logic.

llvm-svn: 264558
2016-03-28 00:03:12 +00:00
Duncan P. N. Exon Smith b42fa2e5c6 BitcodeWriter: Reuse writeMetadataRecords, NFC
Change writeFunctionMetadata to call writeMetadataRecords.  For now
there's no functionality change, but makes it easy to serialize other
types of metadata in the function block in the future.

llvm-svn: 264557
2016-03-27 23:59:32 +00:00
Duncan P. N. Exon Smith cffd8cb9dc BitcodeWriter: Rename some functions for consistency, NFC
To match writeMetadataRecords, writeNamedMetadata and
writeMetadataStrings, change:

    WriteModuleMetadata        => writeModuleMetadata
    WriteFunctionLocalMetadata => writeFunctionMetadata
    Write##CLASS               => write##CLASS

The only major change is "FunctionLocal" => "Function".  The point is to
be less specific, in preparation for emitting normal metadata records
inside function metadata blocks (currently we only emit
`LocalAsMetadata` there).

llvm-svn: 264556
2016-03-27 23:56:04 +00:00
Duncan P. N. Exon Smith 80d153f6aa BitcodeWriter: Split out writeMetadataRecords, NFC
Besides being a nice cleanup, this is preparation for reusing the code
in function metadata blocks.

llvm-svn: 264555
2016-03-27 23:53:30 +00:00
Duncan P. N. Exon Smith 5465f0adc4 BitcodeWriter: Restructure WriteFunctionLocalMetadata, NFC
Use an early return to simplify logic.

llvm-svn: 264554
2016-03-27 23:38:36 +00:00
Duncan P. N. Exon Smith 2766e4d488 BitcodeWriter: Simplify tracking of function-local metadata, NFC
We don't really need a separate vector here; instead, point at a range
inside the main MDs array.  This matches how r264551 references the
ranges of strings and non-strings.

llvm-svn: 264552
2016-03-27 23:22:31 +00:00
Duncan P. N. Exon Smith 6565a0d4b2 Reapply ~"Bitcode: Collect all MDString records into a single blob"
Spiritually reapply commit r264409 (reverted in r264410), albeit with a
bit of a redesign.

Firstly, avoid splitting the big blob into multiple chunks of strings.

r264409 imposed an arbitrary limit to avoid a massive allocation on the
shared 'Record' SmallVector.  The bug with that commit only reproduced
when there were more than "chunk-size" strings.  A test for this would
have been useless long-term, since we're liable to adjust the chunk-size
in the future.

Thus, eliminate the motivation for chunk-ing by storing the string sizes
in the blob.  Here's the layout:

    vbr6: # of strings
    vbr6: offset-to-blob
    blob:
       [vbr6]: string lengths
       [char]: concatenated strings

Secondly, make the output of llvm-bcanalyzer readable.

I noticed when debugging r264409 that llvm-bcanalyzer was outputting a
massive blob all in one line.  Past a small number, the strings were
impossible to split in my head, and the lines were way too long.  This
version adds support in llvm-bcanalyzer for pretty-printing.

    <STRINGS abbrevid=4 op0=3 op1=9/> num-strings = 3 {
      'abc'
      'def'
      'ghi'
    }

From the original commit:

Inspired by Mehdi's similar patch, http://reviews.llvm.org/D18342, this
should (a) slightly reduce bitcode size, since there is less record
overhead, and (b) greatly improve reading speed, since blobs are super
cheap to deserialize.

llvm-svn: 264551
2016-03-27 23:17:54 +00:00
Mehdi Amini 385cf28829 Rename ModuleSummaryIndex::modPathStringEntries() into modulePaths()
It now return the map instead of an iterator.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 264489
2016-03-26 03:35:38 +00:00
Teresa Johnson aae2610042 [ThinLTO] Rename edges() to calls() for clarity (NFC)
Helps distinguish from refs() which iterates over non-call references.

llvm-svn: 264445
2016-03-25 18:59:13 +00:00
Duncan P. N. Exon Smith fc8110041f Revert "Bitcode: Collect all MDString records into a single blob"
This reverts commit r264409 since it failed to bootstrap:
http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto_build/8302/

llvm-svn: 264410
2016-03-25 15:22:27 +00:00
Duncan P. N. Exon Smith fdbf0a5af8 Bitcode: Collect all MDString records into a single blob
Optimize output of MDStrings in bitcode.  This emits them in big blocks
(currently 1024) in a pair of records:
  - BULK_STRING_SIZES: the sizes of the strings in the block, and
  - BULK_STRING_DATA: a single blob, which is the concatenation of all
    the strings.

Inspired by Mehdi's similar patch, http://reviews.llvm.org/D18342, this
should (a) slightly reduce bitcode size, since there is less record
overhead, and (b) greatly improve reading speed, since blobs are super
cheap to deserialize.

I needed to add support for blobs to streaming input to get the test
suite passing.
  - StreamingMemoryObject::getPointer reads ahead and returns the
    address of the blob.
  - To avoid a possible reallocation of StreamingMemoryObject::Bytes,
    BitstreamCursor::readRecord needs to move the call to JumpToEnd
    forward so that getPointer is the last bitstream operation.

llvm-svn: 264409
2016-03-25 14:40:18 +00:00
Duncan P. N. Exon Smith bdde9e1f21 Bitcode: Use std::stable_partition for reproducible builds
Caught by inspection while working on partitioning metadata.  It's nice
to produce the same bitcode if you run the compiler twice.

llvm-svn: 264381
2016-03-25 02:20:28 +00:00
Duncan P. N. Exon Smith 68f5624356 Bitcode: Stop using MODULE_CODE_METADATA_VALUES
The motivation for MODULE_CODE_METADATA_VALUES was to enable an
-flto=thin scheme where:

 1. First, one function is cherry-picked from a bitcode file.
 2. Later, another function is cherry-picked.
 3. Later, ...
 4. Finally, the metadata needed by all the previous functions is
    loaded.

This was abandoned in favour of:

 1. Calculate the superset of functions needed from a Module.
 2. Link all functions at once.

Delayed metadata reading no longer serves a purpose.  It also adds
a few complication, since we can't count on metadata being properly
parsed when exiting the BitcodeReader.  After discussing with Teresa, we
agreed to remove it.

The code that depended on this was removed/updated in r264326.

llvm-svn: 264378
2016-03-25 01:29:50 +00:00
Duncan P. N. Exon Smith a5e25a5563 BitcodeWriter: Move abbreviation for GenericDINode; almost NFC
Simplify ValueEnumerator and WriteModuleMetadata by shifting the logic
for the METADATA_GENERIC_DEBUG abbreviation into WriteGenericDINode.
(This is just like r264302, but for GenericDINode.)

The only change is that the abbreviation is emitted later in the
bitcode, just before the first `GenericDINode` record.  This shouldn't
be observable though.

llvm-svn: 264303
2016-03-24 16:30:18 +00:00
Duncan P. N. Exon Smith 625fda2714 BitcodeWriter: Move abbreviation for DILocation; almost NFC
Simplify ValueEnumerator and WriteModuleMetadata by shifting the logic
for the METADATA_LOCATION abbreviation into WriteDILocation.

The only change is that the abbreviation is emitted later in the
bitcode, just before the first `DILocation` record.  This shouldn't be
observable though.

llvm-svn: 264302
2016-03-24 16:25:51 +00:00
Duncan P. N. Exon Smith f8ecdf5284 BitcodeWriter: Split out named metadata; almost NFC
Split writeNamedMetadata out of WriteModuleMetadata to write named
metadata, and createNamedMetadataAbbrev for the abbreviation.

There should be no effective functionality change, although the layout
of the bitcode will change.  Previously, the abbreviation was emitted at
the top of the block, but now it is delayed until immediately before the
named metadata records are emitted.

llvm-svn: 264301
2016-03-24 16:16:08 +00:00
Duncan P. N. Exon Smith 0b7243ee38 Bitcode: Module* -> Module&, NFC
llvm-svn: 264299
2016-03-24 16:01:46 +00:00
Easwaran Raman 12b79aa0f1 Add getBlockProfileCount method to BlockFrequencyInfo
Differential Revision: http://reviews.llvm.org/D18233

llvm-svn: 264179
2016-03-23 18:18:26 +00:00
Teresa Johnson 1396809b17 [ThinLTO] Record all global variable defs in the summary
Record all variable defs with a summary record to aid in building a
complete reference graph and locating constant variable defs to import.

llvm-svn: 263576
2016-03-15 19:35:45 +00:00
Teresa Johnson 2794f71575 BitcodeWriter dyn_cast cleanup for r263275 (NFC)
Address review suggestions from dblaikie: change a few dyn_cast to cast
and fold a cast into if condition.

llvm-svn: 263526
2016-03-15 02:41:29 +00:00
Teresa Johnson 26ab5772b0 [ThinLTO] Renaming of function index to module summary index (NFC)
(Resubmitting after fixing missing file issue)

With the changes in r263275, there are now more than just functions in
the summary. Completed the renaming of data structures (started in
r263275) to reflect the wider scope. In particular, changed the
FunctionIndex* data structures to ModuleIndex*, and renamed related
variables and comments. Also renamed the files to reflect the changes.

A companion clang patch will immediately succeed this patch to reflect
this renaming.

llvm-svn: 263513
2016-03-15 00:04:37 +00:00
Teresa Johnson cec0cae313 Revert "[ThinLTO] Renaming of function index to module summary index (NFC)"
This reverts commit r263490. Missed a file.

llvm-svn: 263493
2016-03-14 21:18:10 +00:00
Teresa Johnson 892920b358 [ThinLTO] Renaming of function index to module summary index (NFC)
With the changes in r263275, there are now more than just functions in
the summary. Completed the renaming of data structures (started in
r263275) to reflect the wider scope. In particular, changed the
FunctionIndex* data structures to ModuleIndex*, and renamed related
variables and comments. Also renamed the files to reflect the changes.

A companion clang patch will immediately succeed this patch to reflect
this renaming.

llvm-svn: 263490
2016-03-14 21:05:56 +00:00
David Majnemer 90a021fb02 [Bitcode] Make writeComdats less strange
It had a weird artificial limitation on the write side: the comdat name
couldn't be bigger than 2**16.  However, the reader had no such
limitation.  Make the reader and the writer agree.

llvm-svn: 263377
2016-03-13 08:01:03 +00:00
Teresa Johnson 76a1c1d0ba [ThinLTO] Support for reference graph in per-module and combined summary.
Summary:
This patch adds support for including a full reference graph including
call graph edges and other GV references in the summary.

The reference graph edges can be used to make importing decisions
without materializing any source modules, can be used in the plugin
to make file staging decisions for distributed build systems, and is
expected to have other uses.

The call graph edges are recorded in each function summary in the
bitcode via a list of <CalleeValueIds, StaticCount> tuples when no PGO
data exists, or <CalleeValueId, StaticCount, ProfileCount> pairs when
there is PGO, where the ValueId can be mapped to the function GUID via
the ValueSymbolTable. In the function index in memory, the call graph
edges reference the target via the CalleeGUID instead of the
CalleeValueId.

The reference graph edges are recorded in each summary record with a
list of referenced value IDs, which can be mapped to value GUID via the
ValueSymbolTable.

Addtionally, a new summary record type is added to record references
from global variable initializers. A number of bitcode records and data
structures have been renamed to reflect the newly expanded scope of the
summary beyond functions. More cleanup will follow.

Reviewers: joker.eph, davidxl

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D17212

llvm-svn: 263275
2016-03-11 18:52:24 +00:00
Mehdi Amini 83efea89e8 Bitcode writer: fix a typo, using getName() instead of getSourceFileName()
When emitting the source filename, the encoding of the string
was checked against the name instead of the filename.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 261019
2016-02-16 22:07:03 +00:00
Teresa Johnson e1164de5d0 Restore "[ThinLTO] Use MD5 hash in function index." with fix
This restores commit r260408, along with a fix for a bot failure.

The bot failure was caused by dereferencing a unique_ptr in the same
call instruction parameter list where it was passed via std::move.
Apparently due to luck this was not exposed when I built the compiler
with clang, only with gcc.

llvm-svn: 260442
2016-02-10 21:55:02 +00:00
Teresa Johnson 89f38fb5cc Revert "[ThinLTO] Use MD5 hash in function index." due to bot failure
This reverts commit r260408. Bot failure that I need to investigate.

llvm-svn: 260412
2016-02-10 19:11:15 +00:00
Teresa Johnson 0919a84071 [ThinLTO] Use MD5 hash in function index.
Summary:
This patch uses the lower 64-bits of the MD5 hash of a function name as
a GUID in the function index, instead of storing function names. Any
local functions are first given a global name by prepending the original
source file name. This is the same naming scheme and GUID used by PGO in
the indexed profile format.

This change has a couple of benefits. The primary benefit is size
reduction in the combined index file, for example 483.xalancbmk's
combined index file was reduced by around 70%. It should also result in
memory savings for the index file in memory, as the in-memory map is
also indexed by the hash instead of the string.

Second, this enables integration with indirect call promotion, since the
indirect call profile targets are recorded using the same global naming
convention and hash. This will enable the function importer to easily
locate function summaries for indirect call profile targets to enable
their import and subsequent promotion.

The original source file name is recorded in the bitcode in a new
module-level record for use in the ThinLTO backend pipeline.

Reviewers: davidxl, joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D17028

llvm-svn: 260408
2016-02-10 18:57:54 +00:00
Teresa Johnson 79d4e2f3a5 Fix VST_CODE_* bitcode id comments (NFC)
llvm-svn: 260382
2016-02-10 15:02:51 +00:00
Teresa Johnson 5e22e4461d [ThinLTO] Include linkage type in function summary
Summary:
Adds the linkage type to both the per-module and combined function
summaries, which subsumes the current islocal bit. This will eventually
be used to optimized linkage types based on global summary-based
analysis.

Reviewers: joker.eph

Subscribers: joker.eph, davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D16943

llvm-svn: 259993
2016-02-06 16:07:35 +00:00
Teresa Johnson 2d9da4dc50 [ThinLTO] Ensure function summary output order is stable
Iterate over the function list instead of a DenseMap of Function pointers
when emitting the function summary into the module.

This fixes PR26419.

llvm-svn: 259398
2016-02-01 20:16:35 +00:00
Yaron Keren eb2a25467e Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith r259192 post commit comment.
clang part in r259232, this is the LLVM part of the patch.

llvm-svn: 259240
2016-01-29 20:50:44 +00:00
Akira Hatanaka 4f472a8867 [llvm-bcanalyzer] Dump bitcode wrapper header
This patch enables llvm-bcanalyzer to print the bitcode wrapper header
if the file has one, which is needed to test the changes made in
r258627 (bitcode-wrapper-header-armv7m.ll is the test case for r258627).

Differential Revision: http://reviews.llvm.org/D16642

llvm-svn: 259162
2016-01-29 05:55:09 +00:00
Benjamin Kramer 391be792f2 One more batch of self-containing headers.
llvm-svn: 258974
2016-01-27 19:29:56 +00:00
Benjamin Kramer 45275a4d3c Make more headers self-contained.
A lot of this comes from the new complete type requirement of DenseMap.

llvm-svn: 258956
2016-01-27 18:03:37 +00:00
Chris Bieneman e49730d4ba Remove autoconf support
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html

"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi

Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark

Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D16471

llvm-svn: 258861
2016-01-26 21:29:08 +00:00
Akira Hatanaka 1235d280d8 [Bitcode] Insert the darwin wrapper at the beginning of a file when the
target is macho.

It looks like the check for macho was accidentally dropped in r132959.

I don't have a test case, but I'll add one if anyone knows how this can
be tested.

llvm-svn: 258627
2016-01-23 16:02:10 +00:00
Chris Ray b541a3488f NFC Test Commit whitespace change in a comment
Changed whitespace so comments line up.

llvm-svn: 258151
2016-01-19 18:01:20 +00:00
Justin Bogner a43eacbf9e Bitcode: Fix reading and writing of ConstantDataVectors of halfs
In r254991 I allowed ConstantDataVectors to contain elements of
HalfTy, but I missed updating the bitcode reader and writer to handle
this, so now we crash if we try to emit bitcode on programs that have
constant vectors of half.

This fixes the issue and adds test coverage for reading and writing
constant sequences in bitcode.

llvm-svn: 256982
2016-01-06 22:31:32 +00:00
Teresa Johnson 61b406ec75 Rename MDValue* to Metadata* (NFC)
Renamed MDValue* to Metadata*, and MDValueToValIDMap to MetadataToIDs,
as per review for r255909.

llvm-svn: 256593
2015-12-29 23:00:22 +00:00
Vedant Kumar 3a63fb316c Re-reapply "[IR] Move optional data in llvm::Function into a hungoff uselist"
Make personality functions, prefix data, and prologue data hungoff
operands of Function.

This is based on the email thread "[RFC] Clean up the way we store
optional Function data" on llvm-dev.

Thanks to sanjoyd, majnemer, rnk, loladiro, and dexonsmith for feedback!

Includes a fix to scrub value subclass data in dropAllReferences. Does not
use binary literals.

Differential Revision: http://reviews.llvm.org/D13829

llvm-svn: 256095
2015-12-19 08:52:49 +00:00
Vedant Kumar 44dd9871e8 Revert "Reapply "[IR] Move optional data in llvm::Function into a hungoff uselist""
This reverts commit r256093.

This broke lld-x86_64-win7 because of -Werror,-Wc++1y-extensions.

llvm-svn: 256094
2015-12-19 08:48:43 +00:00
Vedant Kumar d481752e68 Reapply "[IR] Move optional data in llvm::Function into a hungoff uselist"
Make personality functions, prefix data, and prologue data hungoff
operands of Function.

This is based on the email thread "[RFC] Clean up the way we store
optional Function data" on llvm-dev.

Thanks to sanjoyd, majnemer, rnk, loladiro, and dexonsmith for feedback!

Includes a fix to scrub value subclass data in dropAllReferences.

Differential Revision: http://reviews.llvm.org/D13829

llvm-svn: 256093
2015-12-19 08:29:51 +00:00
Vedant Kumar e069c4b6d1 Revert "[IR] Move optional data in llvm::Function into a hungoff uselist"
This reverts commit r256090.

This broke llvm-clang-lld-x86_64-debian-fast.

llvm-svn: 256091
2015-12-19 07:30:44 +00:00
Vedant Kumar be7525d4fa [IR] Move optional data in llvm::Function into a hungoff uselist
Make personality functions, prefix data, and prologue data hungoff
operands of Function.

This is based on the email thread "[RFC] Clean up the way we store
optional Function data" on llvm-dev.

Thanks to sanjoyd, majnemer, rnk, loladiro, and dexonsmith for feedback!

Differential Revision: http://reviews.llvm.org/D13829

llvm-svn: 256090
2015-12-19 07:08:56 +00:00
Vaivaswatha Nagaraj fb3f4907c0 Add InaccessibleMemOnly and inaccessibleMemOrArgMemOnly attributes
Summary:
This patch introduces two new function attributes 

InaccessibleMemOnly: This attribute indicates that the function may only access memory that is not accessible by the program/IR being compiled. This is a weaker form of ReadNone.
inaccessibleMemOrArgMemOnly: This attribute indicates that the function may only access memory that is either not accessible by the program/IR being compiled, or is pointed to by its pointer arguments. This is a weaker form of  ArgMemOnly

Test cases have been updated. This revision uses this (d001932f3a) as reference.

Reviewers: jmolloy, hfinkel

Subscribers: reames, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D15499

llvm-svn: 255778
2015-12-16 16:16:19 +00:00
Sanjay Patel fa54acedd1 add fast-math-flags to 'call' instructions (PR21290)
This patch adds optional fast-math-flags (the same that apply to fmul/fadd/fsub/fdiv/frem/fcmp)
to call instructions in IR. Follow-up patches would use these flags in LibCallSimplifier, add 
support to clang, and extend FMF to the DAG for calls.

Motivating example:

%y = fmul fast float %x, %x
%z = tail call float @sqrtf(float %y)

We'd like to be able to optimize sqrt(x*x) into fabs(x). We do this today using a function-wide
attribute for unsafe-math, but we really want to trigger on the instructions themselves:

%z = tail call fast float @sqrtf(float %y)

because in an LTO build it's possible that calls with fast semantics have been inlined into a
function with non-fast semantics.

The code changes and tests are based on the recent commits that added "notail":
http://reviews.llvm.org/rL252368

and added FMF to fcmp:
http://reviews.llvm.org/rL241901

Differential Revision: http://reviews.llvm.org/D14707

llvm-svn: 255555
2015-12-14 21:59:03 +00:00
David Majnemer bbfc7219ef [IR] Remove terminatepad
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function.  This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.

Depends on D15478.

Differential Revision: http://reviews.llvm.org/D15479

llvm-svn: 255522
2015-12-14 18:34:23 +00:00
David Majnemer 8a1c45d6e8 [IR] Reformulate LLVM's EH funclet IR
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
  but they are difficult to explain to others, even to seasoned LLVM
  experts.
- catchendpad and cleanupendpad are optimization barriers.  They cannot
  be split and force all potentially throwing call-sites to be invokes.
  This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
  It is unsplittable, starts a funclet, and has control flow to other
  funclets.
- The nesting relationship between funclets is currently a property of
  control flow edges.  Because of this, we are forced to carefully
  analyze the flow graph to see if there might potentially exist illegal
  nesting among funclets.  While we have logic to clone funclets when
  they are illegally nested, it would be nicer if we had a
  representation which forbade them upfront.

Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
  flow, just a bunch of simple operands;  catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
  the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
  the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad.  Their presence can be inferred
  implicitly using coloring information.

N.B.  The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for.  An expert should take a
look to make sure the results are reasonable.

Reviewers: rnk, JosephTremoulet, andrew.w.kaylor

Differential Revision: http://reviews.llvm.org/D15139

llvm-svn: 255422
2015-12-12 05:38:55 +00:00
Amjad Aboud a9bcf16ebc Macro debug info support in LLVM IR
Introduced DIMacro and DIMacroFile debug info metadata in the LLVM IR to support macros.

Differential Revision: http://reviews.llvm.org/D14687

llvm-svn: 255245
2015-12-10 12:56:35 +00:00
Teresa Johnson d4d3dfd8ef [ThinLTO] Add MODULE_CODE_METADATA_VALUES record
Summary:
This is split out from the ThinLTO metadata mapping patch
http://reviews.llvm.org/D14752.

To avoid needing to parse the module level metadata during function
importing, a new module-level record is added which holds the
number of module-level metadata values. This is required because
metadata value ids are assigned implicitly during parsing, and the
function-level metadata ids start after the module-level metadata ids.

I made a change to this version of the code compared to D14752
in order to add more consistent and thorough assertion checking of the
new record value. We now unconditionally use the record value to
initialize the MDValueList size, and handle it the same in parseMetadata
for all module level metadata cases (lazy loading or not).

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D14825

llvm-svn: 253668
2015-11-20 14:51:27 +00:00
Teresa Johnson 12545075f0 Use a different block id for block of metadata kind records
Summary:
There are currently two blocks with the METADATA_BLOCK id at module
scope. The first has the module-level metadata values (consisting of
some combination of METADATA_* record codes except for METADATA_KIND).
The second consists only of METADATA_KIND records. The latter is used
only in the METADATA_ATTACHMENT block within function blocks (for
metadata attached to instructions).

For ThinLTO we want to delay the parsing of module level metadata
until all functions have been imported from that module (there is some
bookkeeping used to suture it up when we read it during a post-pass).
However, we do need the METADATA_KIND records when parsing the function
body during importing, since those kinds are used as described above.

To simplify identification and parsing of just the block containing
the metadata kinds, use a different block id (METADATA_KIND_BLOCK_ID).
Support older bitcode without the new block id as well.

Reviewers: dexonsmith, joker.eph

Subscribers: davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14654

llvm-svn: 253154
2015-11-15 02:00:09 +00:00
Sanjay Patel 225d65f1e6 use range-based for loop; NFCI
llvm-svn: 253048
2015-11-13 16:21:23 +00:00
Sanjoy Das b9ca6dcc6b [OperandBundles] Identify operand bundles with both their names and IDs
No code uses this functionality yet.  This change just exposes
information / structure that was already present.

llvm-svn: 252644
2015-11-10 20:13:15 +00:00
Akira Hatanaka 97cb397132 [Bitcode] Add enums for call instruction markers and flags. NFC.
This commit adds enums in LLVMBitCodes.h to improve readability and
maintainability. This is a follow-up to r252368 which was discussed
here:

http://reviews.llvm.org/D12923

llvm-svn: 252395
2015-11-07 02:48:49 +00:00
Sanjoy Das 54c3ca694a [OperandBundles] Rename accessor, NFC
Rename getOperandBundle to getOperandBundleAt since that's more obvious.

llvm-svn: 252388
2015-11-07 01:56:04 +00:00
Akira Hatanaka 5cfcce12eb Add 'notail' marker for call instructions.
This marker prevents optimization passes from adding 'tail' or
'musttail' markers to a call. Is is used to prevent tail call
optimization from being performed on the call.

rdar://problem/22667622

Differential Revision: http://reviews.llvm.org/D12923

llvm-svn: 252368
2015-11-06 23:55:38 +00:00
James Molloy e6f87ca812 Add a new attribute: norecurse
This attribute allows the compiler to assume that the function never recurses into itself, either directly or indirectly (transitively). This can be used among other things to demote global variables to locals.

llvm-svn: 252282
2015-11-06 10:32:53 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.

This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.

Since this is an IR change, a bitcode upgrade has been provided.

Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.

Differential Revision: http://reviews.llvm.org/D14265

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Mehdi Amini ba19c6eed8 Fix Abbrev emission in WriteIdentificationBlock
This Abbrev was not emitted and basically unused, just leacking there.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 252110
2015-11-05 00:25:03 +00:00
Teresa Johnson f72278f051 Clang format a few prior patches (NFC)
I had clang formatted my earlier patches using the wrong style.
Reformatted with the LLVM style.

llvm-svn: 251812
2015-11-02 18:02:11 +00:00
Mehdi Amini 5d303285b9 Add an (optional) identification block in the bitcode
Processing bitcode from a different LLVM version can lead to
unexpected behavior. The LLVM project guarantees autoupdating
bitcode from a previous minor revision for the same major, but
can't make any promise when reading bitcode generated from a
either a non-released LLVM, a vendor toolchain, or a "future"
LLVM release. This patch aims at being more user-friendly and
allows a bitcode produce to emit an optional block at the
beginning of the bitcode that will contains an opaque string
intended to describe the bitcode producer information. The
bitcode reader will dump this information alongside any error it
reports.

The optional block also includes an "epoch" number, monotonically
increasing when incompatible changes are made to the bitcode. The
reader will reject bitcode whose epoch is different from the one
expected.

Differential Revision: http://reviews.llvm.org/D13666

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 251325
2015-10-26 18:37:00 +00:00
Teresa Johnson 3da931f87a Pass FunctionInfoIndex by reference to WriteFunctionSummaryToFile (NFC)
Implemented suggestion by dblakie in review for r250704.

llvm-svn: 250723
2015-10-19 19:06:06 +00:00
Duncan P. N. Exon Smith 584af871cc BitcodeWriter: Stop using implicit ilist iterator conversion, NFC
Now LLVMBitWriter compiles without implicit ilist iterator conversions.

In these cases, the cleanest thing was to switch to range-based for
loops.  Since there wasn't much noise I converted sub-loops and parent
loops as a drive-by.

llvm-svn: 250144
2015-10-13 03:26:19 +00:00
Teresa Johnson ca6b64ff04 Fix combined function index abbrev (NFC)
Removed an unused abbrev op in the VST_CODE_COMBINED_FNENTRY abbrev.

I noticed while writing/testing an array string dumper for
llvm-bcanalyze that the combined function's VST entry abbrevs contained
an old field that I am not using. Everything was working fine since the
bitcode writer and reader were in sync on how the record fields were
actually being set up and interpreted.

llvm-svn: 249691
2015-10-08 13:52:56 +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
David Blaikie 6a51dbdb3c [opaque pointer types] Add an explicit pointee type to alias records in the IR
Since aliases actually use and verify their explicit type already, no
further invalid testing is required here. The
invalid.test:ALIAS-TYPE-MISMATCH case catches errors due to emitting a
non-pointee type in the new format or a non-pointer type in the old
format.

llvm-svn: 247952
2015-09-17 22:18:59 +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
Teresa Johnson c01e4cbccc Refactor string encoding checks in BitcodeWriter (NFC)
llvm-svn: 247891
2015-09-17 14:37:35 +00:00
Joseph Tremoulet 9ce71f76b9 [WinEH] Add cleanupendpad instruction
Summary:
Add a `cleanupendpad` instruction, used to mark exceptional exits out of
cleanups (for languages/targets that can abort a cleanup with another
exception).  The `cleanupendpad` instruction is similar to the `catchendpad`
instruction in that it is an EH pad which is the target of unwind edges in
the handler and which itself has an unwind edge to the next EH action.
The `cleanupendpad` instruction, similar to `cleanupret` has a `cleanuppad`
argument indicating which cleanup it exits.  The unwind successors of a
`cleanuppad`'s `cleanupendpad`s must agree with each other and with its
`cleanupret`s.

Update WinEHPrepare (and docs/tests) to accomodate `cleanupendpad`.

Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12433

llvm-svn: 246751
2015-09-03 09:09:43 +00:00
Joseph Tremoulet 8220bcc570 [WinEH] Require token linkage in EH pad/ret signatures
Summary:
WinEHPrepare is going to require that cleanuppad and catchpad produce values
of token type which are consumed by any cleanupret or catchret exiting the
pad.  This change updates the signatures of those operators to require/enforce
that the type produced by the pads is token type and that the rets have an
appropriate argument.

The catchpad argument of a `CatchReturnInst` must be a `CatchPadInst` (and
similarly for `CleanupReturnInst`/`CleanupPadInst`).  To accommodate that
restriction, this change adds a notion of an operator constraint to both
LLParser and BitcodeReader, allowing appropriate sentinels to be constructed
for forward references and appropriate error messages to be emitted for
illegal inputs.

Also add a verifier rule (noted in LangRef) that a catchpad with a catchpad
predecessor must have no other predecessors; this ensures that WinEHPrepare
will see the expected linear relationship between sibling catches on the
same try.

Lastly, remove some superfluous/vestigial casts from instruction operand
setters operating on BasicBlocks.

Reviewers: rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12108

llvm-svn: 245797
2015-08-23 00:26:33 +00:00
David Majnemer 0bc0eef71c [IR] Give catchret an optional 'return value' operand
Some personality routines require funclet exit points to be clearly
marked, this is done by producing a token at the funclet pad and
consuming it at the corresponding ret instruction.  CleanupReturnInst
already had a spot for this operand but CatchReturnInst did not.
Other personality routines don't need to use this which is why it has
been made optional.

llvm-svn: 245149
2015-08-15 02:46:08 +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
Yaron Keren 001e2e4228 Rangify for loop, NFC.
llvm-svn: 244434
2015-08-10 07:04:29 +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
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
David Majnemer 654e130b6e New EH representation for MSVC compatibility
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Differential Revision: http://reviews.llvm.org/D11097

llvm-svn: 243766
2015-07-31 17:58:14 +00:00
Bob Wilson 043ee65ef3 Reserve some constant values for the Swift calling convention.
Swift has a custom calling convention that also requires some new flags
on arguments and one new attribute on alloca instructions. This patch
does not include the implementation of that calling convention - that
will be provided as part of the open-source release of Swift; this only
reserves the bitcode constant values so that they are not used for
other purposes.

llvm-svn: 243379
2015-07-28 04:05:45 +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
David Majnemer db82d2f338 Revert the new EH instructions
This reverts commits r241888-r241891, I didn't mean to commit them.

llvm-svn: 241893
2015-07-10 07:15:17 +00:00
David Majnemer ae2ffc8a8c New EH representation for MSVC compatibility
Summary:
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Reviewers: rnk, JosephTremoulet, reames, nlewycky, rjmccall

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11041

llvm-svn: 241888
2015-07-10 07:00:44 +00:00
Adrian Prantl ab1243fe6c Add a DIModule metadata node to the IR.
It is meant to be used to record modules @imported by the current
compile unit, so a debugger an import the same modules to replicate this
environment before dropping into the expression evaluator.

DIModule is a sibling to DINamespace and behaves quite similarly.
In addition to the name of the module it also records the module
configuration details that are necessary to uniquely identify the module.
This includes the configuration macros (e.g., -DNDEBUG), the include path
where the module.map file is to be found, and the isysroot.

The idea is that the backend will turn this into a DW_TAG_module.

http://reviews.llvm.org/D9614
rdar://problem/20965932

llvm-svn: 241017
2015-06-29 23:03:47 +00:00
Pete Cooper 125ad17fed Use foreach loop over constant operands. NFC.
A number of places had explicit loops over Constant::operands().
Just use foreach loops where possible.

llvm-svn: 240694
2015-06-25 20:51:38 +00:00
Alexander Kornienko f00654e31b Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Alexander Kornienko 70bc5f1398 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
Benjamin Kramer 5014f40fa6 [Bitcode] Replace hand-coded little endian handling with Endian.h functions.
No functional change intended.

llvm-svn: 239944
2015-06-17 20:55:30 +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
Duncan P. N. Exon Smith 51149d5589 modules: Add explicit dependency on intrinsics_gen
`LLVM_ENABLE_MODULES` builds sometimes fail because `Intrinsics.td`
needs to regenerate `Instrinsics.h` before anyone can include anything
from the LLVM_IR module.  Represent the dependency explicitly to prevent
that.

llvm-svn: 239796
2015-06-16 00:44:12 +00:00
Peter Collingbourne 82437bf7a5 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
Yaron Keren 4c20debe3c Rangify several for loops in ValueEnumerator constructor.
llvm-svn: 239636
2015-06-12 20:18:20 +00:00
Owen Anderson 85fa7d5037 Add initial support for the convergent attribute.
llvm-svn: 238264
2015-05-26 23:48:40 +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
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
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120
2015-04-29 16:38:44 +00:00
David Blaikie bdb4910202 [opaque pointer type] Encode the allocated type of an alloca rather than its pointer result type.
llvm-svn: 235998
2015-04-28 16:51:01 +00:00
David Blaikie 2a661cd062 [opaque pointer type] Encode the pointee type in the bitcode for 'cmpxchg'
As a space optimization, this instruction would just encode the pointer
type of the first operand and use the knowledge that the second and
third operands would be of the pointee type of the first. When typed
pointers go away, this assumption will no longer be available - so
encode the type of the second operand explicitly and rely on that for
the third.

Test case added to demonstrate the backwards compatibility concern,
which only comes up when the definition of the second operand comes
after the use (hence the weird basic block sequence) - at which point
the type needs to be explicitly encoded in the bitcode and the record
length changes to accommodate this.

llvm-svn: 235966
2015-04-28 04:30:29 +00:00
David Blaikie 1a848da518 [opaque pointer type] encode the pointee type of global variables
Use a few extra bits in the const field (after widening it from a fixed
single bit) to stash the address space which is no longer provided by
the type (and an extra bit in there to specify that we're using that new
encoding).

llvm-svn: 235911
2015-04-27 19:58:56 +00:00
Duncan P. N. Exon Smith 3d4cd756b6 IR: Add assembly/bitcode support for function metadata attachments
Add serialization support for function metadata attachments (added in
r235783).  The syntax is:

    define @foo() !attach !0 {

Metadata attachments are only allowed on functions with bodies.  Since
they come before the `{`, they're not really part of the body; since
they require a body, they're not really part of the header.  In
`LLParser` I gave them a separate function called from `ParseDefine()`,
`ParseOptionalFunctionMetadata()`.

In bitcode, I'm using the same `METADATA_ATTACHMENT` record used by
instructions.  Instruction metadata attachments are included in a
special "attachment" block at the end of a `Function`.  The attachment
records are laid out like this:

    InstID (KindID MetadataID)+

Note that these records always have an odd number of fields.  The new
code takes advantage of this to recognize function attachments (which
don't need an instruction ID):

    (KindID MetadataID)+

This means we can use the same attachment block already used for
instructions.

This is part of PR23340.

llvm-svn: 235785
2015-04-24 22:04:41 +00:00
David Blaikie 5ea1f7b744 [opaque pointer type] bitcode: add explicit callee type to invoke instructions
llvm-svn: 235735
2015-04-24 18:06:06 +00:00
David Blaikie 612ddbfde0 [opaque pointer types] Serialize the value type for store instructions
Without pointee types the space optimization of storing only the pointer
type and not the value type won't be viable - so add the extra type
information that would be missing.

Storeatomic coming soon.

llvm-svn: 235474
2015-04-22 04:14:42 +00:00
David Blaikie 561a157233 [opaque pointer type] Serialize the type of an llvm::Function as a function type rather than a function pointer type
llvm-svn: 235200
2015-04-17 16:28:26 +00:00
David Blaikie dbe6e0f171 [opaque pointer type] Explicit pointee type for call instruction
Use an extra bit in the CCInfo to flag the newer version of the
instructiont hat includes the type explicitly.

Tested the newer error cases I added, but didn't add tests for the finer
granularity improvements to existing error paths.

llvm-svn: 235160
2015-04-17 06:40:14 +00:00
Sanjoy Das 31ea6d1590 [IR] Introduce a dereferenceable_or_null(N) attribute.
Summary:
If a pointer is marked as dereferenceable_or_null(N), LLVM assumes it
is either `null` or `dereferenceable(N)` or both.  This change only
introduces the attribute and adds a token test case for the `llvm-as`
/ `llvm-dis`.  It does not hook up other parts of the optimizer to
actually exploit the attribute -- those changes will come later.

For pointers in address space 0, `dereferenceable(N)` is now exactly
equivalent to `dereferenceable_or_null(N)` && `nonnull`.  For other
address spaces, `dereferenceable(N)` is potentially weaker than
`dereferenceable_or_null(N)` && `nonnull` (since we could have a null
`dereferenceable(N)` pointer).

The motivating case for this change is Java (and other managed
languages), where pointers are either `null` or dereferenceable up to
some usually known-at-compile-time constant offset.

Reviewers: rafael, hfinkel

Reviewed By: hfinkel

Subscribers: nicholas, llvm-commits

Differential Revision: http://reviews.llvm.org/D8650

llvm-svn: 235132
2015-04-16 20:29:50 +00:00
Duncan P. N. Exon Smith 62e0f454a0 DebugInfo: Remove 'inlinedAt:' field from MDLocalVariable
Remove 'inlinedAt:' from MDLocalVariable.  Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.

The 'inlinedAt:' field was used by the backend in two ways:

 1. To tell the backend whether and into what a variable was inlined.
 2. To create a unique id for each inlined variable.

Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).

This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.

If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.

llvm-svn: 235050
2015-04-15 22:29:27 +00:00
Duncan P. N. Exon Smith 8a7b84b4d0 uselistorder: Remove the global bits
Remove all the global bits to do with preserving use-list order by
moving the `cl::opt`s to the individual tools that want them.  There's a
minor functionality change to `libLTO`, in that you can't send in
`-preserve-bc-uselistorder=false`, but making that bit settable (if it's
worth doing) should be through explicit LTO API.

As a drive-by fix, I removed some includes of `UseListOrder.h` that were
made unnecessary by recent commits.

llvm-svn: 234973
2015-04-15 03:14:06 +00:00
Duncan P. N. Exon Smith 679db3345c uselistorder: Pull bit through BitcodeWriterPass
Now the callers of `BitcodeWriterPass` decide whether or not to preserve
bitcode use-list order.

llvm-svn: 234959
2015-04-15 00:34:24 +00:00
Duncan P. N. Exon Smith a052ed6381 uselistorder: Pull the bit through WriteToBitcodFile()
Change the callers of `WriteToBitcodeFile()` to pass `true` or
`shouldPreserveBitcodeUseListOrder()` explicitly.  I left the callers
that want to send `false` alone.

I'll keep pushing the bit higher until hopefully I can delete the global
`cl::opt` entirely.

llvm-svn: 234957
2015-04-15 00:10:50 +00:00
Duncan P. N. Exon Smith 458593a457 uselistorder: Thread bit through ValueEnumerator
Canonicalize access to whether to preserve use-list order in bitcode on
a `bool` stored in `ValueEnumerator`.  Next step, expose this as a
`bool` through `WriteBitcodeToFile()`.

llvm-svn: 234956
2015-04-14 23:45:11 +00:00
Duncan P. N. Exon Smith 7ad0bd54d3 DebugInfo: Make MDSubprogram::getFunction() return Constant
Change `MDSubprogram::getFunction()` and
`MDGlobalVariable::getConstant()` to return a `Constant`.  Previously,
both returned `ConstantAsMetadata`.

llvm-svn: 234699
2015-04-11 20:27:40 +00:00
Duncan P. N. Exon Smith 1134473f51 IR: Remove MDTupleTypedArrayWrapper::operator MDTuple*()
Remove `MDTupleTypedArrayWrapper::operator MDTuple*()`, since it causes
ambiguity (at least in some [1] compilers [2]) when using indexes to
`MDTupleTypedArrayWrapper::operator[](unsigned)` that are convertible to
(but not the same as) `unsigned`.

[1]: http://lab.llvm.org:8011/builders/sanitizer-windows/builds/2308
[2]: http://lab.llvm.org:8011/builders/clang-cmake-mips/builds/4442

llvm-svn: 234326
2015-04-07 16:50:39 +00:00
Duncan P. N. Exon Smith 5dcf621c8a IR: Rename MDSubrange::getLo() to getLowerBound()
During initial review, the `lo:` field was renamed to `lowerBound:`.
Make the same change to the C++ API.

llvm-svn: 234267
2015-04-07 00:39:59 +00:00
Duncan P. N. Exon Smith ab659fb3d0 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.

llvm-svn: 233585
2015-03-30 19:40:05 +00:00
Duncan P. N. Exon Smith 1facf7a13d Bitcode: Reflow code to use early continues, NFC
llvm-svn: 233578
2015-03-30 18:29:18 +00:00
Duncan P. N. Exon Smith 79f8d11d5a AsmWriter: Assert on unresolved metadata nodes
Assert that `MDNode::isResolved()`.  While in theory the `Verifier`
should catch this, it doesn't descend into all debug info, and the
`DebugInfoVerifier` doesn't call into the `Verifier`.  Besides, this
helps to catch bugs when `-disable-verify=true`.

Note that I haven't come across a place where this fails with clang
today, so no testcase.

llvm-svn: 232442
2015-03-17 00:16:35 +00:00
David Blaikie b9263570a5 [opaque pointer type] Bitcode support for explicit type parameter on the gep operator
This happened to be fairly easy to support backwards compatibility based
on the number of operands (old format had an even number, new format has
one more operand so an odd number).

test/Bitcode/old-aliases.ll already appears to test old gep operators
(if I remove the backwards compatibility in the BitcodeReader, this and
another test fail) so I'm not adding extra test coverage here.

llvm-svn: 232216
2015-03-13 21:03:36 +00:00
David Blaikie b5b5efd2d1 [opaque pointer type] Bitcode support for explicit type parameter on GEP.
Like r230414, add bitcode support including backwards compatibility, for
an explicit type parameter to GEP.

At the suggestion of Duncan I tried coalescing the two older bitcodes into a
single new bitcode, though I did hit a wrinkle: I couldn't figure out how to
create an explicit abbreviation for a record with a variable number of
arguments (the indicies to the gep). This means the discriminator between
inbounds and non-inbounds gep is a full variable-length field I believe? Is my
understanding correct? Is there a way to create such an abbreviation? Should I
just use two bitcodes as before?

Reviewers: dexonsmith

Differential Revision: http://reviews.llvm.org/D7736

llvm-svn: 230415
2015-02-25 01:08:52 +00:00
David Blaikie 8503565eec [opaque pointer type] bitcode support for explicit type parameter to the load instruction
Summary:
I've taken my best guess at this, but I've cargo culted in places & so
explanations/corrections would be great.

This seems to pass all the tests (check-all, covering clang and llvm) so I
believe that pretty well exercises both the backwards compatibility and common
(same version) compatibility given the number of checked in bitcode files we
already have. Is that a reasonable approach to testing here? Would some more
explicit tests be desired?

1) is this the right way to do back-compat in this case (looking at the number
  of entries in the bitcode record to disambiguate between the old schema and
  the new?)

2) I don't quite understand the logarithm logic to choose the encoding type of
  the type parameter in the abbreviation description, but I found another
  instruction doing the same thing & it seems to work. Is that the right
  approach?

Reviewers: dexonsmith

Differential Revision: http://reviews.llvm.org/D7655

llvm-svn: 230414
2015-02-25 01:07:20 +00:00
David Blaikie 7b0281089e BitcodeWriter: Refactor common computation of bits required for a type index.
Suggested by Duncan. Happy to bikeshed the name, cache the result, etc.

llvm-svn: 230410
2015-02-25 00:51:52 +00:00
Duncan P. N. Exon Smith ad6eb127c9 Bitcode: Stop assuming non-null fields
When writing the bitcode serialization for the new debug info hierarchy,
I assumed two fields would never be null.

Drop that assumption, since it's brittle (and crashes the
`BitcodeWriter` if wrong), and is a check better left for the verifier
anyway.  (No need for a bitcode upgrade here, since the new hierarchy is
still not in place.)

The fields in question are `MDCompileUnit::getFile()` and
`MDDerivedType::getBaseType()`, the latter of which isn't null in
test/Transforms/Mem2Reg/ConvertDebugInfo2.ll (see !14, a pointer to
nothing).  While the testcase might have bitrotted, there's no reason
for the bitcode format to rely on non-null for metadata operands.

This also fixes a bug in `AsmWriter` where if the `file:` is null it
isn't emitted (caught by the double-round trip in the testcase I'm
adding) -- this is a required field in `LLParser`.

I'll circle back to ConvertDebugInfo2.  Once the specialized nodes are
in place, I'll be trying to turn the debug info verifier back on by
default (in the newer module pass form committed r206300) and throwing
more logic in there.  If the testcase has bitrotted (as opposed to me
not understanding the schema correctly) I'll fix it then.

llvm-svn: 229960
2015-02-20 03:17:58 +00:00