Commit Graph

2387 Commits

Author SHA1 Message Date
Rafael Espindola e9f0784acc Add a CachedHash structure.
A DenseMap doesn't store the hashes, so it needs to recompute them when
the table is resized.

In some applications the hashing cost is noticeable. That is the case
for example in lld for symbol names (StringRef).

This patch adds a templated structure that can wraps any value that can
go in a DenseMap and caches the hash.

llvm-svn: 266981
2016-04-21 12:16:21 +00:00
Duncan P. N. Exon Smith 9738602869 IR: Enable debug info type ODR uniquing for forward decls
Add a new method, DICompositeType::buildODRType, that will create or
mutate the DICompositeType for a given ODR identifier, and use it in
LLParser and BitcodeReader instead of DICompositeType::getODRType.

The logic is as follows:

  - If there's no node, create one with the given arguments.
  - Else, if the current node is a forward declaration and the new
    arguments would create a definition, mutate the node to match the
    new arguments.
  - Else, return the old node.

This adds a missing feature supported by the current DITypeIdentifierMap
(which I'm slowly making redudant).  The only remaining difference is
that the DITypeIdentifierMap has a "the-last-one-wins" rule, whereas
DICompositeType::buildODRType has a "the-first-one-wins" rule.

For now I'm leaving behind DICompositeType::getODRType since it has
obvious, low-level semantics that are convenient for unit testing.

llvm-svn: 266786
2016-04-19 18:00:19 +00:00
Lang Hames 79e096dbaf [Orc] Add pthread dependence to the RPCUtilsTest unit test.
llvm-svn: 266766
2016-04-19 17:13:52 +00:00
Duncan P. N. Exon Smith 1561709d57 IR: LLVMContextTest => DebugTypeODRUniquingTest, NFC
The second test in this file is actually testing DICompositeType API,
not LLVMContext API (after r266742 moved it to a higher level).  This
really doesn't make sense in an LLVMContextTest.  Rename the tests
before adding more.

llvm-svn: 266764
2016-04-19 17:11:06 +00:00
Duncan P. N. Exon Smith 0b0271ef97 IR: getOrInsertODRUniquedType => DICompositeType::getODRType, NFC
Lift the API for debug info ODR type uniquing up a layer.  Instead of
clients managing the map directly on the LLVMContext, add a static
method to DICompositeType called getODRType and handle the map in the
background.  Also adds DICompositeType::getODRTypeIfExists, so far just
for convenience in the unit tests.

This simplifies the logic in LLParser and BitcodeReader.  Because of
argument spam there are actually a few more lines of code now; I'll see
if I come up with a reasonable way to clean that up.

llvm-svn: 266742
2016-04-19 14:55:09 +00:00
Duncan P. N. Exon Smith 86f1bf98dc IR: Require DICompositeType for ODR uniquing type map
Tighten up the API for debug info ODR type uniquing in LLVMContext.  The
only reason to allow other DIType subclasses is to make the unit tests
prettier :/.

llvm-svn: 266737
2016-04-19 14:42:55 +00:00
Lang Hames de33d5901d [Orc] Disable RPC callST unit test until the S390 failures encountered during
http://lab.llvm.org:8011/builders/clang-s390x-linux/builds/3459 can be
debugged/fixed.

llvm-svn: 266717
2016-04-19 06:01:51 +00:00
Duncan P. N. Exon Smith ed8fdb2a0e IR: Rename API for enabling ODR uniquing of DITypes, NFC
As per David's review, rename everything in the new API for ODR type
uniquing of debug info.

    ensureDITypeMap  => enableDebugTypeODRUniquing
    destroyDITypeMap => disableDebugTypeODRUniquing
    hasDITypeMap     => isODRUniquingDebugTypes

llvm-svn: 266713
2016-04-19 04:55:25 +00:00
Lang Hames 679c436c95 [Orc] Tidy up some of the RPC primitives, add a unit-test for the callST
(synchronous call) primitive.

llvm-svn: 266711
2016-04-19 04:43:09 +00:00
Lang Hames 3fde652e18 [Orc] Re-commit r266581 with fixes for MSVC, and format cleanups.
Fixes:

(1) Removes constexpr (unsupported in MSVC)
(2) Move constructors (remove explicitly defaulted ones)
(3) <future> - Add warning suppression for MSVC.

llvm-svn: 266663
2016-04-18 19:55:43 +00:00
Igor Kudrin 1c14dc4c5a Reapply "[Coverage] Prevent detection of false instantiations in case of macro expansion."
The root of the problem was that findMainViewFileID(File, Function)
could return some ID for any given file, even though that file
was not the main file for that function.

This patch ensures that the result of this function is conformed
with the result of findMainViewFileID(Function).

This commit reapplies r266436, which was reverted by r266458,
with the .covmapping file serialized in v1 format.

Differential Revision: http://reviews.llvm.org/D18787

llvm-svn: 266620
2016-04-18 15:36:30 +00:00
Eric Liu d09f15ea6f Revert "Replace the use of MaxFunctionCount module flag"
This reverts commit r266477.

This commit introduces cyclic dependency. This commit has "Analysis" depend on "ProfileData",
while "ProfileData" depends on "Object", which depends on "BitCode", which
depends on "Analysis".

llvm-svn: 266619
2016-04-18 15:31:11 +00:00
Nico Weber ca94d0ec0c Revert 266581 (and follow-up 266588), it doesn't build on Windows.
Three problems:
1. <future> can't be easily used.  If you must use it, see
   include/Support/ThreadPool.h for how.
2. constexpr problems, even after 266588.
3. Move assignment operators can't be defaulted in MSVC2013.

llvm-svn: 266615
2016-04-18 13:57:08 +00:00
Nico Weber dd2ca83795 Unbreak building unit tests on Windows after r266595.
llvm-svn: 266614
2016-04-18 13:54:50 +00:00
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
Lang Hames 236cea74df [ORC] Generalize the ORC RPC utils to support RPC function return values and
asynchronous call/handle. Also updates the ORC remote JIT API to use the new
scheme.

The previous version of the RPC tools only supported void functions, and
required the user to manually call a paired function to return results. This
patch replaces the Procedure typedef (which only supported void functions) with
the Function typedef which supports return values, e.g.:

  Function<FooId, int32_t(std::string)> Foo;

The RPC primitives and channel operations are also expanded. RPC channels must
support four new operations: startSendMessage, endSendMessage,
startRecieveMessage and endRecieveMessage, to handle channel locking. In
addition, serialization support for tuples to RPCChannels is added to enable
multiple return values.

The RPC primitives are expanded from callAppend, call, expect and handle, to:

appendCallAsync - Make an asynchronous call to the given function.

callAsync - The same as appendCallAsync, but calls send on the channel when
            done.

callSTHandling - Blocking call for single-threaded code. Wraps a call to
                 callAsync then waits on the result, using a user-supplied
                 handler to handle any callbacks from the remote.

callST - The same as callSTHandling, except that it doesn't handle
         callbacks - it expects the result to be the first return.

expect and handle - as before.

handleResponse - Handle a response from the remote.

waitForResult - Wait for the response with the given sequence number to arrive.

llvm-svn: 266581
2016-04-18 01:06:49 +00:00
Duncan P. N. Exon Smith 5ab2be094e IR: Use an explicit map for debug info type uniquing
Rather than relying on the structural equivalence of DICompositeType to
merge type definitions, use an explicit map on the LLVMContext that
LLParser and BitcodeReader consult when constructing new nodes.
Each non-forward-declaration DICompositeType with a non-empty
'identifier:' field is stored/loaded from the type map, and the first
definiton will "win".

This map is opt-in: clients that expect ODR types from different modules
to be merged must call LLVMContext::ensureDITypeMap.

  - Clients that just happen to load more than one Module in the same
    LLVMContext won't magically merge types.

  - Clients (like LTO) that want to continue to merge types based on ODR
    identifiers should opt-in immediately.

I have updated LTOCodeGenerator.cpp, the two "linking" spots in
gold-plugin.cpp, and llvm-link (unless -disable-debug-info-type-map) to
set this.

With this in place, it will be straightforward to remove the DITypeRef
concept (i.e., referencing types by their 'identifier:' string rather
than pointing at them directly).

llvm-svn: 266549
2016-04-17 03:58:21 +00:00
Mehdi Amini 47b292d3fd Remove some unneeded headers and replace some headers with forward class declarations (NFC)
Differential Revision: http://reviews.llvm.org/D19154

Patch by Eugene Kosov <claprix@yandex.ru>

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266524
2016-04-16 07:51:28 +00:00
Duncan P. N. Exon Smith a77d073305 ValueMapper: Stop memoizing ConstantAsMetadata
Stop memoizing ConstantAsMetadata in ValueMapper::mapMetadata.  Now we
have to recompute it, but these metadata aren't particularly common, and
it restricts the lifetime of the Metadata map unnecessarily.

(The motivation is that I have a patch which uses a single Metadata map
for the lifetime of IRMover.  Mehdi profiled r266446 with the patch
applied and we saw a pretty big speedup in lib/Linker.)

llvm-svn: 266513
2016-04-16 03:39:44 +00:00
Davide Italiano 0d2ef01589 [DebugInfo] Correct the assertion introduced in r266509 + update test.
llvm-svn: 266512
2016-04-16 03:23:48 +00:00
Duncan P. N. Exon Smith 39423b0294 Reapply "ValueMapper: Eliminate cross-file co-recursion, NFC"
This reverts commit r266507, reapplying r266503 (and r266505
"ValueMapper: Use API from r266503 in unit tests, NFC") completely
unchanged.

I reverted because of a bot failure here:
  http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/16810/

However, looking more closely, the failure was from a host-compiler
crash (clang 3.7.1) when building:
  lib/CodeGen/AsmPrinter/CMakeFiles/LLVMAsmPrinter.dir/DwarfAccelTable.cpp.o

I didn't modify that file, or anything it includes, with that commit.

The next build (which hadn't picked up my revert) got past it:
  http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/16811/

I think this was just unfortunate timing.  I suppose the bot must be
flakey.

llvm-svn: 266510
2016-04-16 02:29:55 +00:00
Duncan P. N. Exon Smith 6fe1ff260b Revert "ValueMapper: Eliminate cross-file co-recursion, NFC"
This reverts commit r266503, in case it's the root cause of this bot
failure:

  http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/16810

I'm also reverting r266505 -- "ValueMapper: Use API from r266503 in unit
tests, NFC" -- since it's in the way.

llvm-svn: 266507
2016-04-16 02:05:33 +00:00
Duncan P. N. Exon Smith 190b232d73 ValueMapper: Use API from r266503 in unit tests, NFC
I'm not in a hurry to migrate all the users, but the unit tests at least
should use the new API.

llvm-svn: 266505
2016-04-16 01:40:24 +00:00
Easwaran Raman f53baca686 Replace the use of MaxFunctionCount module flag
Adds an interface to get ProfileSummary for a module and makes InlineCost use ProfileSummary to get max function count.

Differential Revision: http://reviews.llvm.org/D18622

llvm-svn: 266477
2016-04-15 21:39:58 +00:00
Igor Kudrin e880a06559 Revert "[Coverage] Prevent detection of false instantiations in case of macro expansion."
This reverts commit r266436 as it broke buildbot.

llvm-svn: 266458
2016-04-15 17:53:48 +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
Igor Kudrin 061d496c51 [Coverage] Prevent detection of false instantiations in case of macro expansion.
The root of the problem was that findMainViewFileID(File, Function)
could return some ID for any given file, even though that file
was not the main file for that function.

This patch ensures that the result of this function is conformed
with the result of findMainViewFileID(Function).

Differential Revision: http://reviews.llvm.org/D18787

llvm-svn: 266436
2016-04-15 14:56:50 +00:00
Igor Kudrin df5a831006 [Coverage] Add support for making test data for more than one function.
Differential Revision: http://reviews.llvm.org/D18758

llvm-svn: 266434
2016-04-15 14:46:31 +00:00
Hans Wennborg 40cfde3cb8 Option parser: class for consuming a joined arg in addition to all remaining args
llvm-svn: 266394
2016-04-15 00:23:30 +00:00
Hans Wennborg c940f097f4 OptionParsingTest.cpp: reorder EXPECT_EQs to put expectation on the left. NFC.
This provides for better error messages from the framework when the expected
and actual values don't match.

llvm-svn: 266393
2016-04-15 00:23:15 +00:00
Mehdi Amini 03b42e41bf Remove every uses of getGlobalContext() in LLVM (but the C API)
At the same time, fixes InstructionsTest::CastInst unittest: yes
you can leave the IR in an invalid state and exit when you don't
destroy the context (like the global one), no longer now.

This is the first part of http://reviews.llvm.org/D19094

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266379
2016-04-14 21:59:01 +00:00
Igor Kudrin e4034e3637 [Coverage] Update testing methods to support more than two files
Differential Revision: http://reviews.llvm.org/D18757

llvm-svn: 266289
2016-04-14 10:43:37 +00:00
Duncan P. N. Exon Smith 11f60fd65a ValueMapper: Resolve cycles on the new nodes
Fix a major bug from r265456.  Although it's now much rarer, ValueMapper
sometimes has to duplicate cycles.  The
might-transitively-reference-a-temporary counts don't decrement on their
own when there are cycles, and you need to call MDNode::resolveCycles to
fix it.

r265456 was checking the input nodes to see if they were unresolved.
This is useless; they should never be unresolved.  Instead we should
check the output nodes and resolve cycles on them.

llvm-svn: 266258
2016-04-13 22:54:01 +00:00
Davide Italiano 236e7444dd [DebugInfo] Optimize memory layout of DISubprogram.
A DISubprogram on x86_64 was 48 bytes. During an LTO build we
end up allocating *a lot* of these (see Duncan's numbers on
llvm-dev and/or my numbers in the review link).
This change reduces the size to 40 bytes, with a nice effect
on peak memory usage when LTO'ing clang.
There are more classes in the hierarchy which can be compacted
so more patches will come. DISubprogram was the biggest offender
in my profiling, anyway.

Differential Revision:  http://reviews.llvm.org/D18918

llvm-svn: 266241
2016-04-13 20:17:42 +00:00
Matt Arsenault c394357430 APInt: Add overload of isMask
This mimics the version in MathExtras.h which isn't testing for a
specific mask size.

llvm-svn: 266101
2016-04-12 18:17:23 +00:00
Xinliang David Li 06d6ce227d Fix asan test failure
llvm-svn: 265891
2016-04-10 05:31:29 +00:00
Xinliang David Li 284644838f [PGO] Fix deserialize bug
Raw function pointer collected by value
profile data may be from external functions
that are not instrumented. They won't have
mapping data to be used by the deserializer.
Force the value to be 0 in this case.

llvm-svn: 265890
2016-04-10 03:32:02 +00:00
Xinliang David Li a3e0d45bfd Clean up test case
llvm-svn: 265887
2016-04-10 02:35:53 +00:00
Duncan P. N. Exon Smith 69341e6abc ValueMapper: Don't memoize metadata when RF_NoModuleLevelChanges
Prevent the Metadata side-table in ValueMap from growing unnecessarily
when RF_NoModuleLevelChanges.  As a drive-by, make ValueMap::hasMD,
which apparently had no users until I used it here for testing, actually
compile.

llvm-svn: 265828
2016-04-08 18:49:36 +00:00
Duncan P. N. Exon Smith e05ff7c1a7 ValueMapper: Stop memoizing MDStrings
Stop adding MDString to the Metadata section of the ValueMap in
MapMetadata.  It blows up the size of the map for no benefit, since we
can always return quickly anyway.

There is a potential follow-up that I don't think I'll push on right
away, but maybe someone else is interested:  stop checking for a
pre-mapped MDString, and move the `isa<MDString>()` checks in
Mapper::mapSimpleMetadata and MDNodeMapper::getMappedOp in front of the
`VM.getMappedMD()` calls.  While this would preclude explicitly
remapping MDStrings it would probably be a little faster.

llvm-svn: 265827
2016-04-08 18:47:02 +00:00
Duncan P. N. Exon Smith 4ec55f8ab6 Reapply "ValueMapper: Treat LocalAsMetadata more like function-local Values"
This reverts commit r265765, reapplying r265759 after changing a call from
LocalAsMetadata::get to ValueAsMetadata::get (and adding a unit test).  When a
local value is mapped to a constant (like "i32 %a" => "i32 7"), the new debug
intrinsic operand may no longer be pointing at a local.

    http://lab.llvm.org:8080/green/job/clang-stage1-configure-RA_build/19020/

The previous coommit message follows:

--

This is a partial re-commit -- maybe more of a re-implementation -- of
r265631 (reverted in r265637).

This makes RF_IgnoreMissingLocals behave (almost) consistently between
the Value and the Metadata hierarchy.  In particular:

  - MapValue returns nullptr or "metadata !{}" for missing locals in
    MetadataAsValue/LocalAsMetadata bridging paris, depending on
    the RF_IgnoreMissingLocals flag.

  - MapValue doesn't memoize LocalAsMetadata-related results.

  - MapMetadata no longer deals with LocalAsMetadata or
    RF_IgnoreMissingLocals at all.  (This wasn't in r265631 at all, but
    I realized during testing it would make the patch simpler with no
    loss of generality.)

r265631 went too far, making both functions universally ignore
RF_IgnoreMissingLocals.  This broke building (e.g.) compiler-rt.
Reassociate (and possibly other passes) don't currently maintain
dominates-use invariants for metadata operands, resulting in IR like
this:

    define void @foo(i32 %arg) {
      call void @llvm.some.intrinsic(metadata i32 %x)
      %x = add i32 1, i32 %arg
    }

If the inliner chooses to inline @foo into another function, then
RemapInstruction will call `MapValue(metadata i32 %x)` and assert that
the return is not nullptr.

I've filed PR27273 to add a Verifier check and fix the underlying
problem in the optimization passes.

As a workaround, return `!{}` instead of nullptr for unmapped
LocalAsMetadata when RF_IgnoreMissingLocals is unset.  Otherwise, match
the behaviour of r265631.

Original commit message:

    ValueMapper: Make LocalAsMetadata match function-local Values

    Start treating LocalAsMetadata similarly to function-local members of
    the Value hierarchy in MapValue and MapMetadata.

      - Don't memoize them.
      - Return nullptr if they are missing.

    This also cleans up ConstantAsMetadata to stop listening to the
    RF_IgnoreMissingLocals flag.

llvm-svn: 265768
2016-04-08 03:13:22 +00:00
Duncan P. N. Exon Smith 805873148a Revert "ValueMapper: Treat LocalAsMetadata more like function-local Values"
This reverts commit r265759, since even this limited version breaks some
bots:
  http://lab.llvm.org:8011/builders/clang-ppc64be-linux/builds/3311
  http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/17696

This also reverts r265761 "ValueMapper: Unduplicate
RF_NoModuleLevelChanges check, NFC", since I had trouble separating it
from r265759.

llvm-svn: 265765
2016-04-08 00:56:21 +00:00
Duncan P. N. Exon Smith 267185ec92 ValueMapper: Treat LocalAsMetadata more like function-local Values
This is a partial re-commit -- maybe more of a re-implementation -- of
r265631 (reverted in r265637).

This makes RF_IgnoreMissingLocals behave (almost) consistently between
the Value and the Metadata hierarchy.  In particular:

  - MapValue returns nullptr or "metadata !{}" for missing locals in
    MetadataAsValue/LocalAsMetadata bridging paris, depending on
    the RF_IgnoreMissingLocals flag.

  - MapValue doesn't memoize LocalAsMetadata-related results.

  - MapMetadata no longer deals with LocalAsMetadata or
    RF_IgnoreMissingLocals at all.  (This wasn't in r265631 at all, but
    I realized during testing it would make the patch simpler with no
    loss of generality.)

r265631 went too far, making both functions universally ignore
RF_IgnoreMissingLocals.  This broke building (e.g.) compiler-rt.
Reassociate (and possibly other passes) don't currently maintain
dominates-use invariants for metadata operands, resulting in IR like
this:

    define void @foo(i32 %arg) {
      call void @llvm.some.intrinsic(metadata i32 %x)
      %x = add i32 1, i32 %arg
    }

If the inliner chooses to inline @foo into another function, then
RemapInstruction will call `MapValue(metadata i32 %x)` and assert that
the return is not nullptr.

I've filed PR27273 to add a Verifier check and fix the underlying
problem in the optimization passes.

As a workaround, return `!{}` instead of nullptr for unmapped
LocalAsMetadata when RF_IgnoreMissingLocals is unset.  Otherwise, match
the behaviour of r265631.

Original commit message:

    ValueMapper: Make LocalAsMetadata match function-local Values

    Start treating LocalAsMetadata similarly to function-local members of
    the Value hierarchy in MapValue and MapMetadata.

      - Don't memoize them.
      - Return nullptr if they are missing.

    This also cleans up ConstantAsMetadata to stop listening to the
    RF_IgnoreMissingLocals flag.

llvm-svn: 265759
2016-04-08 00:33:44 +00:00
Duncan P. N. Exon Smith 45601e867d Revert "ValueMapper: Make LocalAsMetadata match function-local Values"
This reverts commit r265631, since it caused bot failures:
http://lab.llvm.org:8011/builders/clang-ppc64be-linux/builds/3256
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-42vma/builds/7272

Looks like something is depending on the old behaviour.  I'll try to
track it down and recommit.

llvm-svn: 265637
2016-04-07 02:10:50 +00:00
Duncan P. N. Exon Smith fdccad925c ValueMapper: Allow RF_IgnoreMissingLocals and RF_NullMapMissingGlobalValues
Remove the assertion that disallowed the combination, since
RF_IgnoreMissingLocals should have no effect on globals.  As it happens,
RF_NullMapMissingGlobalValues asserted in MapValue(Constant*,...), so I
also changed a cast to a cast_or_null to get my test passing.

llvm-svn: 265633
2016-04-07 01:22:45 +00:00
Duncan P. N. Exon Smith c1e4070708 ValueMapper: Make LocalAsMetadata match function-local Values
Start treating LocalAsMetadata similarly to function-local members of
the Value hierarchy in MapValue and MapMetadata.

  - Don't memoize them.
  - Return nullptr if they are missing.

This also cleans up ConstantAsMetadata to stop listening to the
RF_IgnoreMissingLocals flag.

llvm-svn: 265631
2016-04-07 01:08:39 +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 bdfc984679 IRMover: Steal arguments when moving functions, NFC
Instead of copying arguments from the source function to the
destination, steal them.  This has a few advantages.

  - The ValueMap doesn't need to be seeded with (or cleared of)
    Arguments.

  - Often the destination function won't have created any arguments yet,
    so this avoids malloc traffic.

  - Argument names don't need to be copied.

Because argument lists are lazy, this required a new
Function::stealArgumentListFrom helper.

llvm-svn: 265519
2016-04-06 06:38:15 +00:00
Duncan P. N. Exon Smith 91d3cfed78 Revert "Fix Clang-tidy modernize-deprecated-headers warnings in remaining files; other minor fixes."
This reverts commit r265454 since it broke the build.  E.g.:

  http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-incremental_build/22413/

llvm-svn: 265459
2016-04-05 20:45:04 +00:00
Duncan P. N. Exon Smith ea7df770ae ValueMapper: Rewrite Mapper::mapMetadata without recursion
This commit completely rewrites Mapper::mapMetadata (the implementation
of llvm::MapMetadata) using an iterative algorithm.  The guts of the new
algorithm are in MDNodeMapper::map, the entry function in a new class.

Previously, Mapper::mapMetadata performed a recursive exploration of the
graph with eager "just in case there's a reason" malloc traffic.

The new algorithm has these benefits:

  - New nodes and temporaries are not created eagerly.
  - Uniquing cycles are not duplicated (see new unit test).
  - No recursion.

Given a node to map, it does this:

 1. Use a worklist to perform a post-order traversal of the transitively
    referenced unmapped nodes.

 2. Track which nodes will change operands, and which will have new
    addresses in the mapped scheme.  Propagate the changes through the
    POT until fixed point, to pick up uniquing cycles that need to
    change.

 3. Map all the distinct nodes without touching their operands.  If
    RF_MoveDistinctMetadata, they get mapped to themselves; otherwise,
    they get mapped to clones.

 4. Map the uniqued nodes (bottom-up), lazily creating temporaries for
    forward references as needed.

 5. Remap the operands of the distinct nodes.

Mehdi helped me out by profiling this with -flto=thin.  On his workload
(importing/etc. for opt.cpp), MapMetadata sped up by 15%, contributed
about 50% less to persistent memory, and made about 100x fewer calls to
malloc.  The speedup is less than I'd hoped.  The profile mainly blames
DenseMap lookups; perhaps there's a way to reduce them (e.g., by
disallowing remapping of MDString).

It would be nice to break the strange remaining recursion on the Value
side: MapValue => materializeInitFor => RemapInstruction => MapValue.  I
think we could do this by having materializeInitFor return a worklist of
things to be remapped.

llvm-svn: 265456
2016-04-05 20:23:21 +00:00