Commit Graph

34712 Commits

Author SHA1 Message Date
Sam McCall 4bb7883d09 [Support] Add a UniqueStringSaver: like StringSaver, but deduplicating.
Summary: Clarify contract of StringSaver (it null-terminates, callers rely on it).

Reviewers: hokein

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49596

llvm-svn: 337677
2018-07-23 10:44:40 +00:00
Xin Tong 023e25ad14 [ORE] Move loop invariant ORE checks outside the PM loop.
Summary:
This takes 22ms out of ~20s compiling sqlite3.c because we call it
for every unit of compilation and every pass.

Reviewers: paquette, anemet

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D49586

llvm-svn: 337654
2018-07-22 05:27:41 +00:00
Chen Zheng 69bb064539 [InstrSimplify] fold sdiv if two operands are negated and non-overflow
Differential Revision: https://reviews.llvm.org/D49382

llvm-svn: 337642
2018-07-21 12:27:54 +00:00
Aaron Smith 23c2d1c15a [DebugInfo] Add a new DI flag to record if a C++ record is a trivial type
Summary:
This flag is used when emitting debug info and is needed to initialize subprogram and member function attributes (function options) for Codeview. These function options are used to create an accurate compiler type for UDT symbols (class/struct/union) from PDBs.

It is not easy to determine if a C++ record is trivial or not based on the current DICompositeType flags and other accessible debug information from Codeview. For example, without this flag the metadata for a non-trivial C++ record with user-defined ctor and a trivial one with a defaulted ctor are the same.

    struct S { S(); }
    struct S { S() = default; }

This change introduces a new DI flag and corresponding clang::CXXRecordDecl::isTrivial method to set the flag in the frontend.

Reviewers: rnk, zturner, llvm-commits, dblaikie, aleksandr.urakov, deadalnix

Reviewed By: rnk

Subscribers: asmith, probinson, aprantl, JDevlieghere

Differential Revision: https://reviews.llvm.org/D45122

llvm-svn: 337641
2018-07-21 05:42:13 +00:00
Lang Hames 960246dbee [ORC] Re-apply r336760 with fixes.
llvm-svn: 337637
2018-07-21 00:12:05 +00:00
Lang Hames a48d108353 Re-apply r337595 with fix for LLVM_ENABLE_THREADS=Off.
llvm-svn: 337626
2018-07-20 22:22:19 +00:00
Martin Storsjo a6ffc9c8df [COFF] Adjust how we flag weak externals
This fixes PR36096.

Originally based on a patch by Martell Malone.

Differential Revision: https://reviews.llvm.org/D44357

llvm-svn: 337613
2018-07-20 20:48:29 +00:00
Reid Kleckner 7ed83591c2 Revert r337595 "[ORC] Add new symbol lookup methods to ExecutionSessionBase in preparation for"
Breaks the build with LLVM_ENABLE_THREADS=OFF.

llvm-svn: 337608
2018-07-20 20:20:45 +00:00
Lang Hames 732d116a96 [ORC] Add new symbol lookup methods to ExecutionSessionBase in preparation for
deprecating SymbolResolver and AsynchronousSymbolQuery.

Both lookup overloads take a VSO search order to perform the lookup. The first
overload is non-blocking and takes OnResolved and OnReady callbacks. The second
is blocking, takes a boolean flag to indicate whether to wait until all symbols
are ready, and returns a SymbolMap. Both overloads take a RegisterDependencies
function to register symbol dependencies (if any) on the query.

llvm-svn: 337595
2018-07-20 18:31:53 +00:00
Lang Hames d4df0f1733 [ORC] Simplify VSO::lookupFlags to return the flags map.
This discards the unresolved symbols set and returns the flags map directly
(rather than mutating it via the first argument).

The unresolved symbols result made it easy to chain lookupFlags calls, but such
chaining should be rare to non-existant (especially now that symbol resolvers
are being deprecated) so the simpler method signature is preferable.

llvm-svn: 337594
2018-07-20 18:31:52 +00:00
Lang Hames fd0c1e7169 [ORC] Replace SymbolResolvers in the new ORC layers with search orders on VSOs.
A search order is a list of VSOs to be searched linearly to find symbols. Each
VSO now has a search order that will be used when fixing up definitions in that
VSO. Each VSO's search order defaults to just that VSO itself.

This is a first step towards removing symbol resolvers from ORC altogether. In
practice symbol resolvers tended to be used to implement a search order anyway,
sometimes with additional programatic generation of symbols. Now that VSOs
support programmatic generation of definitions via fallback generators, search
orders provide a cleaner way to achieve the desired effect (while removing a lot
of boilerplate).

llvm-svn: 337593
2018-07-20 18:31:50 +00:00
Zachary Turner a219bae1b7 Fix linker failure with Any.
This is due to a difference in MS ABI which is why I didn't see
it locally.  The included fix should work on all compilers.

llvm-svn: 337588
2018-07-20 17:50:53 +00:00
Zachary Turner f435a7eada Add a Microsoft Demangler.
This adds initial support for a demangling library (LLVMDemangle)
and tool (llvm-undname) for demangling Microsoft names.  This
doesn't cover 100% of cases and there are some known limitations
which I intend to address in followup patches, at least until such
time that we have (near) 100% test coverage matching up with all
of the test cases in clang/test/CodeGenCXX/mangle-ms-*.

Differential Revision: https://reviews.llvm.org/D49552

llvm-svn: 337584
2018-07-20 17:27:48 +00:00
Philip Pfaffe 2628620b62 [Any] Fix a typo: didn't use the correct argument
llvm-svn: 337583
2018-07-20 17:24:11 +00:00
Alina Sbirlea 20c2962585 [MemorySSA] Add API to update MemoryPhis, following CFG changes.
Summary:
When splitting predecessors in BasicBlockUtils, we create a new block as an immediate predecessor of the original BB, then we connect a given set of predecessors to the new block.
The API in this patch will be used to update MemoryPhis for this CFG change.
If all predecessors are being moved, we move the MemoryPhi directly. Otherwise we create a new MemoryPhi in the NewBB and populate its incoming values, while deleting them from BB's Phi.
[Split from D45299 for easier review]

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D49156

llvm-svn: 337581
2018-07-20 17:13:05 +00:00
Zachary Turner 862439c7cb Change bool_constant to integral_constant.
bool_constant is C++17.

llvm-svn: 337576
2018-07-20 16:51:55 +00:00
Zachary Turner bf443b9181 Add llvm::Any.
This is analogous to std::any which is only available in C++17.

Differential Revision: https://reviews.llvm.org/D48807

llvm-svn: 337573
2018-07-20 16:39:32 +00:00
Pavel Labath 7f7e60694e DwarfDebug: Reduce duplication in addAccel*** methods
Summary:
Each of the four methods had a dozen lines and was doing almost exactly
the same thing: get the appropriate accelerator table kind and insert an
entry into it. I move this common logic to a helper function and make
these methods delegate to it.

This came up in the context of D49493, where I've needed to make adding
a string to a string pool slightly more complicated, and it seemed to
make sense to do it in one place instead of five.

To make this work I've needed to unify the interface of the AccelTable
data types, as some used to store DIE& and others DIE*. I chose to unify
to a reference as that's what the caller uses.

This technically isn't NFC, because it changes the StringPool used for
apple tables in the DWO case (now it uses the main file like DWARF v5
instead of the DWO file). However, that shouldn't matter, as DWO is not
a thing on apple targets (clang frontend simply ignores -gsplit-dwarf).

Reviewers: JDevlieghere, aprantl, probinson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D49542

llvm-svn: 337562
2018-07-20 15:24:13 +00:00
Duncan P. N. Exon Smith c03b04d533 Reapply "ADT: Shrink size of SmallVector by 8B on 64-bit platforms"
I'm optimistically reverting commit r337511, effectively reapplying
r337504 *without* changes.

The failing bots that had `SmallVector` in the backtrace recovered after
the unrelated commit r337508.  The backtraces looked bogus anyway, with
`SmallVector::size()` calling (e.g.) `ConstantArray::get()`.

Here's the original commit message:

    ADT: Shrink size of SmallVector by 8B on 64-bit platforms

    Represent size and capacity directly as unsigned and calculate
    `end()` using `begin() + size()`.

    This limits the maximum size/capacity of a vector to UINT32_MAX.

    https://reviews.llvm.org/D48518

llvm-svn: 337514
2018-07-20 00:44:58 +00:00
Duncan P. N. Exon Smith 42f20f3c55 Revert "ADT: Shrink size of SmallVector by 8B on 64-bit platforms"
This reverts commit r337504 while I investigate a TSan bot failure that
seems related:

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/26526

    #8 0x000055581f2895d8 (/b/sanitizer-x86_64-linux-autoconf/build/tsan_debug_build/bin/clang-7+0x1eb45d8)
    #9 0x000055581f294323 llvm::ConstantAggrKeyType<llvm::ConstantArray>::create(llvm::ArrayType*) const /b/sanitizer-x86_64-linux-autoconf/build/llvm/lib/IR/ConstantsContext.h:409:0
    #10 0x000055581f294323 llvm::ConstantUniqueMap<llvm::ConstantArray>::create(llvm::ArrayType*, llvm::ConstantAggrKeyType<llvm::ConstantArray>, std::pair<unsigned int, std::pair<llvm::ArrayType*, llvm::ConstantAggrKeyType<llvm::ConstantArray> > >&) /b/sanitizer-x86_64-linux-autoconf/build/llvm/lib/IR/ConstantsContext.h:635:0
    #11 0x000055581f294323 llvm::ConstantUniqueMap<llvm::ConstantArray>::getOrCreate(llvm::ArrayType*, llvm::ConstantAggrKeyType<llvm::ConstantArray>) /b/sanitizer-x86_64-linux-autoconf/build/llvm/lib/IR/ConstantsContext.h:654:0
    #12 0x000055581f2944cb llvm::ConstantArray::get(llvm::ArrayType*, llvm::ArrayRef<llvm::Constant*>) /b/sanitizer-x86_64-linux-autoconf/build/llvm/lib/IR/Constants.cpp:964:0
    #13 0x000055581fa27e19 llvm::SmallVectorBase::size() const /b/sanitizer-x86_64-linux-autoconf/build/llvm/include/llvm/ADT/SmallVector.h:53:0
    #14 0x000055581fa27e19 llvm::SmallVectorImpl<llvm::Constant*>::resize(unsigned long) /b/sanitizer-x86_64-linux-autoconf/build/llvm/include/llvm/ADT/SmallVector.h:347:0
    #15 0x000055581fa27e19 (anonymous namespace)::EmitArrayConstant(clang::CodeGen::CodeGenModule&, clang::ConstantArrayType const*, llvm::Type*, unsigned int, llvm::SmallVectorImpl<llvm::Constant*>&, llvm::Constant*) /b/sanitizer-x86_64-linux-autoconf/build/llvm/tools/clang/lib/CodeGen/CGExprConstant.cpp:669:0

llvm-svn: 337511
2018-07-20 00:09:56 +00:00
Duncan P. N. Exon Smith 6acb8cee05 ADT: Shrink size of SmallVector by 8B on 64-bit platforms
Representing size and capacity directly as unsigned and calculate
`end()` using `begin() + size()`.

This limits the maximum size/capacity of a vector to UINT32_MAX.

https://reviews.llvm.org/D48518

llvm-svn: 337504
2018-07-19 22:29:47 +00:00
Reid Kleckner 056904599b Work around bug in mingw-w64 GCC 8.1.0
This particular version of GCC seems to break bitfields when a method
appears between two bitfield members.

Personally, I think it's nice to keep bitfields close together so that
it's easy to check how things are packed, so I moved the method after
SubClassData.

Fixes PR38168.

llvm-svn: 337495
2018-07-19 20:32:45 +00:00
Teresa Johnson 28023dbed7 [ThinLTO] Enable ThinLTO WholeProgramDevirt and LowerTypeTests in new PM
Summary:
Enable these passes for CFI and WPD in ThinLTO and LTO with the new pass
manager. Add a couple of tests for both PMs based on the clang tests
tools/clang/test/CodeGen/thinlto-distributed-cfi*.ll, but just test
through llvm-lto2 and not with distributed ThinLTO.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D49429

llvm-svn: 337461
2018-07-19 14:51:32 +00:00
Serge Guelton 7ca1269cd5 Use std::reference_wrapper instead of llvm::ReferenceStorage
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D49298

llvm-svn: 337444
2018-07-19 09:24:34 +00:00
Andrea Di Biagio cd8f627c37 [TargetInstPredicate] Add definition of CheckInvalidRegisterOperand.
This should have been part of r337378. I forgot to svn add it before committing
the change.

llvm-svn: 337380
2018-07-18 11:16:31 +00:00
Simon Pilgrim e2c615dca1 Fix -Wdocumentation warning. NFCI.
llvm-svn: 337368
2018-07-18 09:10:18 +00:00
Peter Collingbourne bd9d313d5c CodeGen: Add a target option for emitting .addrsig directives for all address-significant symbols.
Differential Revision: https://reviews.llvm.org/D48143

llvm-svn: 337331
2018-07-17 22:40:08 +00:00
Peter Collingbourne 3e22733698 MC: Implement support for new .addrsig and .addrsig_sym directives.
Part of the address-significance tables proposal:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123514.html

Differential Revision: https://reviews.llvm.org/D47744

llvm-svn: 337328
2018-07-17 22:17:18 +00:00
Zachary Turner 8a0efd0919 Add some helper functions to the demangle utility classes.
These are all methods that, while not currently used in the
Itanium demangler, are generally useful enough that it's
likely the itanium demangler could find a use for them.  More
importantly, they are all necessary for the Microsoft demangler
which is up and coming in a subsequent patch.  Rather than
combine these into a single monolithic patch, I think it makes
sense to commit this utility code first since it is very simple,
this way it won't detract from the substance of the MS demangler
patch.

llvm-svn: 337316
2018-07-17 19:42:29 +00:00
Florian Hahn 4a53bc63c2 Revert rL337292 due to another MSVC STL problem.
llvm-svn: 337303
2018-07-17 17:12:50 +00:00
Florian Hahn c491c2b955 Recommit r334887: [SmallSet] Add SmallSetIterator.
Spell out destructor, copy/move constructor and assignment operators for
MSVC STL, where set<T>::const_iterator is not trivially copy constructible.

llvm-svn: 337292
2018-07-17 15:24:19 +00:00
whitequark 7c4a074505 [LLVM-C] Add target triple normalization to the C API.
rL333307 was introduced to remove automatic target triple
normalization when calling sys::getDefaultTargetTriple(), arguing
that users of the latter already called Triple::normalize()
if necessary. However, users of the C API currently have no way of
doing target triple normalization.

This patch introduces an LLVMNormalizeTargetTriple function to
the C API which wraps Triple::normalize() and can be used on
the result of LLVMGetDefaultTargetTriple to achieve the same effect.

Differential Revision: https://reviews.llvm.org/D49414

Reviewed By: whitequark

llvm-svn: 337263
2018-07-17 10:57:39 +00:00
Sam Clegg cf2a9e28b1 [WebAssembly] Remove ELF file support.
This support was partial and temporary.  Now that we have
wasm object file support its no longer needed.

Differential Revision: https://reviews.llvm.org/D48744

llvm-svn: 337222
2018-07-16 23:09:29 +00:00
Sanjay Patel c71adc8040 [Intrinsics] define funnel shift IR intrinsics + DAG builder support
As discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2018-May/123292.html
http://lists.llvm.org/pipermail/llvm-dev/2018-July/124400.html

We want to add rotate intrinsics because the IR expansion of that pattern is 4+ instructions, 
and we can lose pieces of the pattern before it gets to the backend. Generalizing the operation 
by allowing 2 different input values (plus the 3rd shift/rotate amount) gives us a "funnel shift" 
operation which may also be a single hardware instruction.

Initially, I thought we needed to define new DAG nodes for these ops, and I spent time working 
on that (much larger patch), but then I concluded that we don't need it. At least as a first 
step, we have all of the backend support necessary to match these ops...because it was required. 
And shepherding these through the IR optimizer is the primary concern, so the IR intrinsics are 
likely all that we'll ever need.

There was also a question about converting the intrinsics to the existing ROTL/ROTR DAG nodes
(along with improving the oversized shift documentation). Again, I don't think that's strictly 
necessary (as the test results here prove). That can be an efficiency improvement as a small 
follow-up patch.

So all we're left with is documentation, definition of the IR intrinsics, and DAG builder support. 

Differential Revision: https://reviews.llvm.org/D49242

llvm-svn: 337221
2018-07-16 22:59:31 +00:00
Fangrui Song cb0bab86b3 [CodeGen] Fix inconsistent declaration parameter name
llvm-svn: 337200
2018-07-16 18:51:40 +00:00
Teresa Johnson d68935c5ac Restore "[ThinLTO] Ensure we always select the same function copy to import"
This reverts commit r337081, therefore restoring r337050 (and fix in
r337059), with test fix for bot failure described after the original
description below.

In order to always import the same copy of a linkonce function,
even when encountering it with different thresholds (a higher one then a
lower one), keep track of the summary we decided to import.
This ensures that the backend only gets a single definition to import
for each GUID, so that it doesn't need to choose one.

Move the largest threshold the GUID was considered for import into the
current module out of the ImportMap (which is part of a larger map
maintained across the whole index), and into a new map just maintained
for the current module we are computing imports for. This saves some
memory since we no longer have the thresholds maintained across the
whole index (and throughout the in-process backends when doing a normal
non-distributed ThinLTO build), at the cost of some additional
information being maintained for each invocation of ComputeImportForModule
(the selected summary pointer for each import).

There is an additional map lookup for each callee being considered for
importing, however, this was able to subsume a map lookup in the
Worklist iteration that invokes computeImportForFunction. We also are
able to avoid calling selectCallee if we already failed to import at the
same or higher threshold.

I compared the run time and peak memory for the SPEC2006 471.omnetpp
benchmark (running in-process ThinLTO backends), as well as for a large
internal benchmark with a distributed ThinLTO build (so just looking at
the thin link time/memory). Across a number of runs with and without
this change there was no significant change in the time and memory.

(I tried a few other variations of the change but they also didn't
improve time or peak memory).

The new commit removes a test that no longer makes sense
(Transforms/FunctionImport/hotness_based_import2.ll), as exposed by the
reverse-iteration bot. The test depends on the order of processing the
summary call edges, and actually depended on the old problematic
behavior of selecting more than one summary for a given GUID when
encountered with different thresholds. There was no guarantee even
before that we would eventually pick the linkonce copy with the hottest
call edges, it just happened to work with the test and the old code, and
there was no guarantee that we would end up importing the selected
version of the copy that had the hottest call edges (since the backend
would effectively import only one of the selected copies).

Reviewers: davidxl

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D48670

llvm-svn: 337184
2018-07-16 15:30:27 +00:00
Roman Lebedev de506632aa [X86][AArch64][DAGCombine] Unfold 'check for [no] signed truncation' pattern
Summary:

[[ https://bugs.llvm.org/show_bug.cgi?id=38149 | PR38149 ]]

As discussed in https://reviews.llvm.org/D49179#1158957 and later,
the IR for 'check for [no] signed truncation' pattern can be improved:
https://rise4fun.com/Alive/gBf
^ that pattern will be produced by Implicit Integer Truncation sanitizer,
https://reviews.llvm.org/D48958 https://bugs.llvm.org/show_bug.cgi?id=21530
in signed case, therefore it is probably a good idea to improve it.

But the IR-optimal patter does not lower efficiently, so we want to undo it..

This handles the simple pattern.
There is a second pattern with predicate and constants inverted.

NOTE: we do not check uses here. we always do the transform.

Reviewers: spatel, craig.topper, RKSimon, javed.absar

Reviewed By: spatel

Subscribers: kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D49266

llvm-svn: 337166
2018-07-16 12:44:10 +00:00
Jonas Devlieghere 98062cb396 [AccelTable] Provide DWARF5AccelTableStaticData for dsymutil.
For dsymutil we want to store offsets in the accelerator table entries
rather than DIE pointers. In addition, we need a way to communicate
which CU a DIE belongs to. This patch provides support for both of these
issues.

Differential revision: https://reviews.llvm.org/D49102

llvm-svn: 337158
2018-07-16 10:52:27 +00:00
Alexandros Lamprineas f854ce84c4 [MemorySSAUpdater] Remove deleted trivial Phis from active workset
Bug fix for PR37808. The regression test is a reduced version of the
original reproducer attached to the bug report. As stated in the report,
the problem was that InsertedPHIs was keeping dangling pointers to
deleted Memory-Phis. MemoryPhis are created eagerly and sometimes get
zapped shortly afterwards. I've used WeakVH instead of an expensive
removal operation from the active workset.

Differential Revision: https://reviews.llvm.org/D48372

llvm-svn: 337149
2018-07-16 07:51:27 +00:00
Michael J. Spencer 7bb2767fba Recommit r335794 "Add support for generating a call graph profile from Branch Frequency Info." with fix for removed functions.
llvm-svn: 337140
2018-07-16 00:28:24 +00:00
Andrea Di Biagio ff630c2cdc [llvm-mca][BtVer2] teach how to identify false dependencies on partially written
registers.

The goal of this patch is to improve the throughput analysis in llvm-mca for the
case where instructions perform partial register writes.

On x86, partial register writes are quite difficult to model, mainly because
different processors tend to implement different register merging schemes in
hardware.

When the code contains partial register writes, the IPC (instructions per
cycles) estimated by llvm-mca tends to diverge quite significantly from the
observed IPC (using perf).

Modern AMD processors (at least, from Bulldozer onwards) don't rename partial
registers. Quoting Agner Fog's microarchitecture.pdf:
" The processor always keeps the different parts of an integer register together.
For example, AL and AH are not treated as independent by the out-of-order
execution mechanism. An instruction that writes to part of a register will
therefore have a false dependence on any previous write to the same register or
any part of it."

This patch is a first important step towards improving the analysis of partial
register updates. It changes the semantic of RegisterFile descriptors in
tablegen, and teaches llvm-mca how to identify false dependences in the presence
of partial register writes (for more details: see the new code comments in
include/Target/TargetSchedule.h - class RegisterFile).

This patch doesn't address the case where a write to a part of a register is
followed by a read from the whole register.  On Intel chips, high8 registers
(AH/BH/CH/DH)) can be stored in separate physical registers. However, a later
(dirty) read of the full register (example: AX/EAX) triggers a merge uOp, which
adds extra latency (and potentially affects the pipe usage).
This is a very interesting article on the subject with a very informative answer
from Peter Cordes:
https://stackoverflow.com/questions/45660139/how-exactly-do-partial-registers-on-haswell-skylake-perform-writing-al-seems-to

In future, the definition of RegisterFile can be extended with extra information
that may be used to identify delays caused by merge opcodes triggered by a dirty
read of a partial write.

Differential Revision: https://reviews.llvm.org/D49196

llvm-svn: 337123
2018-07-15 11:01:38 +00:00
Teresa Johnson b78c5d0602 Revert "[ThinLTO] Ensure we always select the same function copy to import"
This reverts commits r337050 and r337059. Caused failure in
reverse-iteration bot that needs more investigation.

llvm-svn: 337081
2018-07-14 01:45:49 +00:00
Vedant Kumar d37e078d39 Fix comments which mixed up 'before' and 'after', NFC
llvm-svn: 337061
2018-07-13 22:39:31 +00:00
Vedant Kumar 47f2844c76 Clarify wording of a doxygen comment, NFC
llvm-svn: 337060
2018-07-13 22:39:29 +00:00
Teresa Johnson d94c0594d9 [ThinLTO] Ensure we always select the same function copy to import
In order to always import the same copy of a linkonce function,
even when encountering it with different thresholds (a higher one then a
lower one), keep track of the summary we decided to import.
This ensures that the backend only gets a single definition to import
for each GUID, so that it doesn't need to choose one.

Move the largest threshold the GUID was considered for import into the
current module out of the ImportMap (which is part of a larger map
maintained across the whole index), and into a new map just maintained
for the current module we are computing imports for. This saves some
memory since we no longer have the thresholds maintained across the
whole index (and throughout the in-process backends when doing a normal
non-distributed ThinLTO build), at the cost of some additional
information being maintained for each invocation of ComputeImportForModule
(the selected summary pointer for each import).

There is an additional map lookup for each callee being considered for
importing, however, this was able to subsume a map lookup in the
Worklist iteration that invokes computeImportForFunction. We also are
able to avoid calling selectCallee if we already failed to import at the
same or higher threshold.

I compared the run time and peak memory for the SPEC2006 471.omnetpp
benchmark (running in-process ThinLTO backends), as well as for a large
internal benchmark with a distributed ThinLTO build (so just looking at
the thin link time/memory). Across a number of runs with and without
this change there was no significant change in the time and memory.

(I tried a few other variations of the change but they also didn't
improve time or peak memory).

Reviewers: davidxl

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D48670

llvm-svn: 337050
2018-07-13 21:35:51 +00:00
Vlad Tsyrklevich cd1559366d [LowerTypeTests] Limit when icall jumptable entries are emitted
Summary:
Currently LowerTypeTests emits jumptable entries for all live external
and address-taken functions; however, we could limit the number of
functions that we emit entries for significantly.

For Cross-DSO CFI, we continue to emit jumptable entries for all
exported definitions.  In the non-Cross-DSO CFI case, we only need to
emit jumptable entries for live functions that are address-taken in live
functions. This ignores exported functions and functions that are only
address taken in dead functions. This change uses ThinLTO summary data
(now emitted for all modules during ThinLTO builds) to determine
address-taken and liveness info.

The logic for emitting jumptable entries is more conservative in the
regular LTO case because we don't have summary data in the case of
monolithic LTO builds; however, once summaries are emitted for all LTO
builds we can unify the Thin/monolithic LTO logic to only use summaries
to determine the liveness of address taking functions.

This change is a partial fix for PR37474. It reduces the build size for
nacl_helper by ~2-3%, the reduction is due to nacl_helper compiling in
lots of unused code and unused functions that are address taken in dead
functions no longer being being considered live due to emitted jumptable
references. The reduction for chromium is ~0.1-0.2%.

Reviewers: pcc, eugenis, javed.absar

Reviewed By: pcc

Subscribers: aheejin, dexonsmith, dschuff, mehdi_amini, eraman, steven_wu, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D47652

llvm-svn: 337038
2018-07-13 19:57:39 +00:00
Jonas Devlieghere 327e7a1608 [dwarfdump] Add pretty printer for accelerator table based on Atom.
For instance, When dumping .apple_types, the second atom represents the
DW_TAG. In addition to printing the raw value, we now also pretty print
the value if the ATOM tells us how.

llvm-svn: 337026
2018-07-13 17:21:51 +00:00
Evgeniy Stepanov ca8c2f7638 Revert "CallGraphSCCPass: iterate over all functions."
This reverts commit r336419: use-after-free on CallGraph::FunctionMap elements
due to the use of a stale iterator in CGPassManager::runOnModule.

The iterator may be invalidated if a pass removes a function, ex.:
  llvm::LegacyInlinerBase::inlineCalls
  inlineCallsImpl
  llvm::CallGraph::removeFunctionFromModule

llvm-svn: 337018
2018-07-13 16:32:31 +00:00
Joel Galenson 06e7e5798f [cfi-verify] Support AArch64.
This patch adds support for AArch64 to cfi-verify.

This required three changes to cfi-verify.  First, it generalizes checking if an instruction is a trap by adding a new isTrap flag to TableGen (and defining it for x86 and AArch64).  Second, the code that ensures that the operand register is not clobbered between the CFI check and the indirect call needs to allow a single dereference (in x86 this happens as part of the jump instruction).  Third, we needed to ensure that return instructions are not counted as indirect branches.  Technically, returns are indirect branches and can be covered by CFI, but LLVM's forward-edge CFI does not protect them, and x86 does not consider them, so we keep that behavior.

In addition, we had to improve AArch64's code to evaluate the branch target of a MCInst to handle calls where the destination is not the first operand (which it often is not).

Differential Revision: https://reviews.llvm.org/D48836

llvm-svn: 337007
2018-07-13 15:19:33 +00:00
Ulrich Weigand c48aefb63b [TableGen] Support multi-alternative pattern fragments
A TableGen instruction record usually contains a DAG pattern that will
describe the SelectionDAG operation that can be implemented by this
instruction. However, there will be cases where several different DAG
patterns can all be implemented by the same instruction. The way to
represent this today is to write additional patterns in the Pattern
(or usually Pat) class that map those extra DAG patterns to the
instruction. This usually also works fine.

However, I've noticed cases where the current setup seems to require
quite a bit of extra (and duplicated) text in the target .td files.
For example, in the SystemZ back-end, there are quite a number of
instructions that can implement an "add-with-overflow" operation.
The same instructions also need to be used to implement just plain
addition (simply ignoring the extra overflow output). The current
solution requires creating extra Pat pattern for every instruction,
duplicating the information about which particular add operands
map best to which particular instruction.

This patch enhances TableGen to support a new PatFrags class, which
can be used to encapsulate multiple alternative patterns that may
all match to the same instruction.  It operates the same way as the
existing PatFrag class, except that it accepts a list of DAG patterns
to match instead of just a single one.  As an example, we can now define
a PatFrags to match either an "add-with-overflow" or a regular add
operation:

  def z_sadd : PatFrags<(ops node:$src1, node:$src2),
                        [(z_saddo node:$src1, node:$src2),
                         (add node:$src1, node:$src2)]>;

and then use this in the add instruction pattern:

  defm AR : BinaryRRAndK<"ar", 0x1A, 0xB9F8, z_sadd, GR32, GR32>;

These SystemZ target changes are implemented here as well.


Note that PatFrag is now defined as a subclass of PatFrags, which
means that some users of internals of PatFrag need to be updated.
(E.g. instead of using PatFrag.Fragment you now need to use
!head(PatFrag.Fragments).)


The implementation is based on the following main ideas:
- InlinePatternFragments may now replace each original pattern
  with several result patterns, not just one.
- parseInstructionPattern delays calling InlinePatternFragments
  and InferAllTypes.  Instead, it extracts a single DAG match
  pattern from the main instruction pattern.
- Processing of the DAG match pattern part of the main instruction
  pattern now shares most code with processing match patterns from
  the Pattern class.
- Direct use of main instruction patterns in InferFromPattern and
  EmitResultInstructionAsOperand is removed; everything now operates
  solely on DAG match patterns.


Reviewed by: hfinkel

Differential Revision: https://reviews.llvm.org/D48545

llvm-svn: 336999
2018-07-13 13:18:00 +00:00