Commit Graph

25 Commits

Author SHA1 Message Date
George Burgess IV 2a84e4ab12 [MemorySSA] Remove redundant assert; NFC
The `if (!Def && !Use) return nullptr;` right above this assert sort of
defeats the purpose.

llvm-svn: 329632
2018-04-09 22:45:14 +00:00
Zhaoshi Zheng a5531f287a [MemorySSA] Fix spelling errors in MemorySSA.cpp. NFC
llvm-svn: 329230
2018-04-04 21:08:11 +00:00
Mandeep Singh Grang 97bcade70f [Analysis] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer D44363 for a list of all the required patches.

Reviewers: sanjoy, dexonsmith, hfinkel, RKSimon

Reviewed By: dexonsmith

Subscribers: david2050, llvm-commits

Differential Revision: https://reviews.llvm.org/D44944

llvm-svn: 328925
2018-04-01 01:46:51 +00:00
George Burgess IV af0b06f4fd [MemorySSA] Turn an assert into a condition
Eli pointed out that variadic functions are totally a thing, so this
assert is incorrect.

No test-case is provided, since the only way this assert fires is if a
specific DenseMap falls back to doing `isEqual` checks, and that seems
fairly brittle (and requires a pyramid of growing
`call void (i8, ...) @varargs(i8 0)`).

llvm-svn: 328755
2018-03-29 03:12:03 +00:00
George Burgess IV 3588fd4865 [MemorySSA] Consider callsite args for hashing and equality.
We use a `DenseMap<MemoryLocOrCall, MemlocStackInfo>` to keep track of
prior work when optimizing uses in MemorySSA. Because we weren't
accounting for callsite arguments in either the hash code or equality
tests for `MemoryLocOrCall`s, we optimized uses too aggressively in
some rare cases.

Fix by Daniel Berlin.

Should fix PR36883.

llvm-svn: 328748
2018-03-29 00:54:39 +00:00
George Burgess IV 44477c61a0 [MemorySSA] Fix comment + remove redundant dyn_casts; NFC
StartingAccess is already a MemoryUseOrDef.

llvm-svn: 327235
2018-03-11 04:16:12 +00:00
Alina Sbirlea d90c9f4a3c Expose must/may alias info in MemorySSA.
Summary:
Building MemorySSA gathers alias information for Defs/Uses.
Store and expose this information when optimizing uses (when building MemorySSA),
and when optimizing defs or updating uses (getClobberingMemoryAccess).
Current patch does not propagate alias information through MemoryPhis.

Reviewers: gbiv, dberlin

Subscribers: Prazek, sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D38569

llvm-svn: 327035
2018-03-08 18:03:14 +00:00
George Burgess IV 612cf21ec7 [MemorySSA] Call the correct dtors
It appears that there were many cases where we were directly (through
templates) calling the dtor of MemoryAccess, which is conceptually an
abstract class.

This hasn't been a problem, since the data members of all of the
subclasses of MemoryAccess have been POD. I'm planning on changing that.
:)

llvm-svn: 326175
2018-02-27 06:43:19 +00:00
George Burgess IV 6f49f4a951 [MemorySSA] Remove a redundant dyn_cast.
StartingAccess is a MemoryUseOrDef. No need to check again.

llvm-svn: 326000
2018-02-24 00:15:21 +00:00
George Burgess IV 68ac941780 [MemorySSA] Fix a cache invalidation bug with removed accesses
I suspect there's a deeper issue here, but we probably shouldn't be
using INVALID_MEMORYSSA_ID as liveOnEntry's ID anyway.

llvm-svn: 325971
2018-02-23 23:07:18 +00:00
Alina Sbirlea ca741a87f2 [MemorySSA] Allow reordering of loads that alias in the presence of volatile loads.
Summary:
Make MemorySSA allow reordering of two loads that may alias, when one is volatile.
This makes MemorySSA less conservative and behaving the same as the AliasSetTracker.
For more context, see D16875.

LLVM language reference: "The optimizers must not change the number of volatile operations or change their order of execution relative to other volatile operations. The optimizers may change the order of volatile operations relative to non-volatile operations. This is not Java’s “volatile” and has no cross-thread synchronization behavior."

Reviewers: george.burgess.iv, dberlin

Subscribers: sanjoy, reames, hfinkel, llvm-commits, Prazek

Differential Revision: https://reviews.llvm.org/D41525

llvm-svn: 321382
2017-12-22 19:54:03 +00:00
Alina Sbirlea 63d2250a42 Modify ModRefInfo values using static inline method abstractions [NFC].
Summary:
The aim is to make ModRefInfo checks and changes more intuitive
and less error prone using inline methods that abstract the bit operations.

Ideally ModRefInfo would become an enum class, but that change will require
a wider set of changes into FunctionModRefBehavior.

Reviewers: sanjoy, george.burgess.iv, dberlin, hfinkel

Subscribers: nlopes, llvm-commits

Differential Revision: https://reviews.llvm.org/D40749

llvm-svn: 319821
2017-12-05 20:12:23 +00:00
Hans Wennborg 70e22d121d Fix r318786
llvm-svn: 318787
2017-11-21 18:00:01 +00:00
Nuno Lopes 5c122882ed removed unused private method decl. NFC
llvm-svn: 318786
2017-11-21 17:53:19 +00:00
Aaron Ballman 615eb47035 Reverting r315590; it did not include changes for llvm-tblgen, which is causing link errors for several people.
Error LNK2019 unresolved external symbol "public: void __cdecl `anonymous namespace'::MatchableInfo::dump(void)const " (?dump@MatchableInfo@?A0xf4f1c304@@QEBAXXZ) referenced in function "public: void __cdecl `anonymous namespace'::AsmMatcherEmitter::run(class llvm::raw_ostream &)" (?run@AsmMatcherEmitter@?A0xf4f1c304@@QEAAXAEAVraw_ostream@llvm@@@Z) llvm-tblgen D:\llvm\2017\utils\TableGen\AsmMatcherEmitter.obj 1

llvm-svn: 315854
2017-10-15 14:32:27 +00:00
Don Hinton 3e0199f7eb [dump] Remove NDEBUG from test to enable dump methods [NFC]
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.

Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.

Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.

Differential Revision: https://reviews.llvm.org/D38406

llvm-svn: 315590
2017-10-12 16:16:06 +00:00
Eugene Zelenko bb1b2d09cf [Analysis] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 311048
2017-08-16 22:07:40 +00:00
Alina Sbirlea 967e7966fc Allow None as a MemoryLocation to getModRefInfo
Summary:
Adding part of the changes in D30369 (needed to make progress):
Current patch updates AliasAnalysis and MemoryLocation, but does _not_ clean up MemorySSA.

Original summary from D30369, by dberlin:
Currently, we have instructions which affect memory but have no memory
location. If you call, for example, MemoryLocation::get on a fence,
it asserts. This means things specifically have to avoid that. It
also means we end up with a copy of each API, one taking a memory
location, one not.

This starts to fix that.

We add MemoryLocation::getOrNone as a new call, and reimplement the
old asserting version in terms of it.

We make MemoryLocation optional in the (Instruction, MemoryLocation)
version of getModRefInfo, and kill the old one argument version in
favor of passing None (it had one caller). Now both can handle fences
because you can just use MemoryLocation::getOrNone on an instruction
and it will return a correct answer.

We use all this to clean up part of MemorySSA that had to handle this difference.

Note that literally every actual getModRefInfo interface we have could be made private and replaced with:

getModRefInfo(Instruction, Optional<MemoryLocation>)
and
getModRefInfo(Instruction, Optional<MemoryLocation>, Instruction, Optional<MemoryLocation>)

and delegating to the right ones, if we wanted to.

I have not attempted to do this yet.

Reviewers: dberlin, davide, dblaikie

Subscribers: sanjoy, hfinkel, chandlerc, llvm-commits

Differential Revision: https://reviews.llvm.org/D35441

llvm-svn: 309641
2017-08-01 00:28:29 +00:00
NAKAMURA Takumi 5869ba8792 Analysis/MemorySSA.cpp: Prune unused "llvm/Transforms/Scalar.h".
llvm-svn: 308162
2017-07-17 04:31:26 +00:00
Simon Pilgrim 7ce9926ce4 Strip UTF8 BOM that got added for some reason in rL305163
llvm-svn: 305282
2017-06-13 09:58:27 +00:00
Simon Pilgrim 516938452f Fix unused variable warning on non-debug EXPENSIVE_CHECKS builds
llvm-svn: 305163
2017-06-11 12:49:29 +00:00
Davide Italiano 83122058cf [MemorySSA] preservesAll() implies preserves<MemorySSA>(). NFCI.
llvm-svn: 305160
2017-06-11 01:05:45 +00:00
Reid Kleckner 96ab8726a3 [IR] De-virtualize ~Value to save a vptr
Summary:
Implements PR889

Removing the virtual table pointer from Value saves 1% of RSS when doing
LTO of llc on Linux. The impact on time was positive, but too noisy to
conclusively say that performance improved. Here is a link to the
spreadsheet with the original data:

https://docs.google.com/spreadsheets/d/1F4FHir0qYnV0MEp2sYYp_BuvnJgWlWPhWOwZ6LbW7W4/edit?usp=sharing

This change makes it invalid to directly delete a Value, User, or
Instruction pointer. Instead, such code can be rewritten to a null check
and a call Value::deleteValue(). Value objects tend to have their
lifetimes managed through iplist, so for the most part, this isn't a big
deal.  However, there are some places where LLVM deletes values, and
those places had to be migrated to deleteValue.  I have also created
llvm::unique_value, which has a custom deleter, so it can be used in
place of std::unique_ptr<Value>.

I had to add the "DerivedUser" Deleter escape hatch for MemorySSA, which
derives from User outside of lib/IR. Code in IR cannot include MemorySSA
headers or call the MemoryAccess object destructors without introducing
a circular dependency, so we need some level of indirection.
Unfortunately, no class derived from User may have any virtual methods,
because adding a virtual method would break User::getHungOffOperands(),
which assumes that it can find the use list immediately prior to the
User object. I've added a static_assert to the appropriate OperandTraits
templates to help people avoid this trap.

Reviewers: chandlerc, mehdi_amini, pete, dberlin, george.burgess.iv

Reviewed By: chandlerc

Subscribers: krytarowski, eraman, george.burgess.iv, mzolotukhin, Prazek, nlewycky, hans, inglorion, pcc, tejohnson, dberlin, llvm-commits

Differential Revision: https://reviews.llvm.org/D31261

llvm-svn: 303362
2017-05-18 17:24:10 +00:00
Bryant Wong c819ba8874 MemorySSA: Stop tracking def-or-use blocks.
The tracking is unused, since MemoryPhis are not pruned as of r282419.

Differential Revision: https://reviews.llvm.org/D32121

llvm-svn: 300428
2017-04-16 19:45:51 +00:00
Daniel Berlin 554dcd8c89 MemorySSA: Move to Analysis, from Transforms/Utils. It's used as
Analysis, it has Analysis passes, and once NewGVN is made an Analysis,
this removes the cross dependency from Analysis to Transform/Utils.
NFC.

llvm-svn: 299980
2017-04-11 20:06:36 +00:00