Commit Graph

179 Commits

Author SHA1 Message Date
Reid Kleckner
d6b4b10a39 Prefer addAttr(Attribute::AttrKind) over the AttributeList overload
This should simplify the call sites, which typically want to tweak one
attribute at a time. It should also avoid creating ephemeral
AttributeLists that live forever.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300718 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-19 17:28:52 +00:00
Daniel Berlin
e0f5ddbc01 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299980 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-11 20:06:36 +00:00
Reid Kleckner
6707770d48 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298393 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-21 16:57:19 +00:00
Reid Kleckner
1c19be8a98 Remove getArgumentList() in favor of arg_begin(), args(), etc
Users often call getArgumentList().size(), which is a linear way to get
the number of function arguments. arg_size(), on the other hand, is
constant time.

In general, the fact that arguments are stored in an iplist is an
implementation detail, so I've removed it from the Function interface
and moved all other users to the argument container APIs (arg_begin(),
arg_end(), args(), arg_size()).

Reviewed By: chandlerc

Differential Revision: https://reviews.llvm.org/D31052

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298010 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-16 22:59:15 +00:00
Daniel Berlin
188bef38fc Move updating functions to MemorySSAUpdater.
Add updater to passes that now need it.
Move around code in MemorySSA to expose needed functions.

Summary: Mostly cleanup

Reviewers: george.burgess.iv

Subscribers: llvm-commits, Prazek

Differential Revision: https://reviews.llvm.org/D30221

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295887 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-22 22:19:55 +00:00
Daniel Berlin
4f1c254f51 MemorySSA: Add support for renaming uses in the updater.
Summary:
This lets one add aliasing stores to the updater.
(i'm next going to move the creation/etc functions to the updater)

Reviewers: george.burgess.iv

Subscribers: llvm-commits, Prazek

Differential Revision: https://reviews.llvm.org/D30154

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295677 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-20 22:26:03 +00:00
Sanjoy Das
56ccc1cdbf [JumpThreading] Re-enable JumpThreading for guards
Summary:
JumpThreading for guards feature has been reverted at https://reviews.llvm.org/rL295200
due to the following problem: the feature used the following algorithm for detection of
diamond patters:

1. Find a block with 2 predecessors;
2. Check that these blocks have a common single parent;
3. Check that the parent's terminator is a branch instruction.

The problem is that these checks are insufficient. They may pass for a non-diamond
construction in case if those two predecessors are actually the same block. This may
happen if parent's terminator is a br (either conditional or unconditional) to a block
that ends with "switch" instruction with exactly two branches going to one block.

This patch re-enables the JumpThreading for guards and fixes this issue by adding the
check that those found predecessors are actually different blocks. This guarantees that
parent's terminator is a conditional branch with exactly 2 different successors, which
is now ensured by assertions. It also adds two more tests for this situation (with parent's
terminator being a conditional and an unconditional branch).

Patch by Max Kazantsev!

Reviewers: anna, sanjoy, reames

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30036

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295410 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-17 04:21:14 +00:00
Anna Thomas
49d7488ea9 Revert "[JumpThreading] Thread through guards"
This reverts commit r294617.

We fail on an assert while trying to get a condition from an
unconditional branch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295200 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-15 17:08:29 +00:00
Sanjoy Das
f206bf2145 [JumpThreading] Thread through guards
Summary:
This patch allows JumpThreading also thread through guards.
Virtually, guard(cond) is equivalent to the following construction:

  if (cond) { do something } else {deoptimize}

Yet it is not explicitly converted into IFs before lowering.
This patch enables early threading through guards in simple cases.
Currently it covers the following situation:

  if (cond1) {
    // code A
  } else {
    // code B
  }
  // code C
  guard(cond2)
  // code D

If there is implication cond1 => cond2 or !cond1 => cond2, we can transform
this construction into the following:

  if (cond1) {
    // code A
    // code C
  } else {
    // code B
    // code C
    guard(cond2)
  }
  // code D

Thus, removing the guard from one of execution branches.

Patch by Max Kazantsev!

Reviewers: reames, apilipenko, igor-laevsky, anna, sanjoy

Reviewed By: sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29620

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294617 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-09 19:40:22 +00:00
Chandler Carruth
869cf60647 [PM] Defend against getting slightly wrong template arguments passed
into CRTP base classes.

This can sometimes happen and not cause an immediate failure when the
derived class is, itself, a template. You can end up essentially calling
methods on the wrong derived type but a type where many things will
appear to "work".

To fail fast and with a clear error message we can use a static_assert,
but we have to stash that static_assert inside a method body or nested
type that won't need to be completed while building the base class. I've
tried to pick a reasonably small number of places that seemed like they
would definitely get triggered on use.

This is the last of the patch series defending against this that I have
planned, so far no bugs other than the original were found.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294275 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-07 03:34:08 +00:00
Daniel Berlin
be1b992213 Revert "[MemorySSA] Revert r293361 and r293363, as the tests fail under asan."
This reverts commit r293471, reapplying r293361 and r293363 with a fix
for an out-of-bounds read.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293474 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-30 11:35:39 +00:00
Sam McCall
b6af32432c [MemorySSA] Revert r293361 and r293363, as the tests fail under asan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293471 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-30 09:19:50 +00:00
Daniel Berlin
09e759d8e9 MemorySSA: Allow movement to arbitrary places
Summary: Extend the MemorySSAUpdater API to allow movement to arbitrary places

Reviewers: davide, george.burgess.iv

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29239

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293363 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-28 02:26:39 +00:00
Daniel Berlin
92cf58ee36 MemorySSA: Move updater to its own file
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293357 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-28 01:35:02 +00:00
Daniel Berlin
f6dfcde86b Introduce a basic MemorySSA updater, that supports insertDef,
insertUse, moveBefore and moveAfter operations.

Summary:
This creates a basic MemorySSA updater that handles arbitrary
insertion of uses and defs into MemorySSA, as well as arbitrary
movement around the CFG. It replaces the current splice API.

It can be made to handle arbitrary control flow changes.
Currently, it uses the same updater algorithm from D28934.

The main difference is because MemorySSA is single variable, we have
the complete def and use list, and don't need anyone to give it to us
as part of the API.  We also have to rename stores below us in some
cases.

If we go that direction in that patch, i will merge all the updater
implementations (using an updater_traits or something to provide the
get* functions we use, called read*/write* in that patch).

Sadly, the current SSAUpdater algorithm is way too slow to use for
what we are doing here.

I have updated the tests we have to basically build memoryssa
incrementally using the updater api, and make sure it still comes out
the same.

Reviewers: george.burgess.iv

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29047

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293356 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-28 01:23:13 +00:00
Daniel Berlin
db632c77aa MemorySSA: Link all defs together into an intrusive defslist, to make updater easier
Summary:
This is the first in a series of patches to add a simple, generalized updater to MemorySSA.

For MemorySSA, every def is may-def, instead of the normal must-def.
(the best way to think of memoryssa is "everything is really one variable, with different versions of that variable at different points in the program).
This means when updating, we end up having to do a bunch of work to touch defs below and above us.

In order to support this quickly, i have ilist'd all the defs for each block.  ilist supports tags, so this is quite easy. the only slightly messy part is that you can't have two iplists for the same type that differ only whether they have the ownership part enabled or not, because the traits are for the value type.

The verifiers have been updated to test that the def order is correct.

Reviewers: george.burgess.iv

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29046

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293085 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-25 20:56:19 +00:00
Chandler Carruth
3710416022 [PM] Teach the loop PM to run LoopSimplify prior to the loop pipeline.
This adds the last remaining core feature of the loop pass pipeline in
the new PM and removes the last of the really egregious hacks in the
LICM tests.

Sadly, this requires really substantial changes in the unittests in
order to provide and maintain simplified loops. This is particularly
hard because for example LoopSimplify will try to fold undef branches to
an ideal direction and simplify the loop accordingly.

Differential Revision: https://reviews.llvm.org/D28766

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292709 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-21 03:48:51 +00:00
Peter Collingbourne
1d08431d77 Cloning: Copy comdats when cloning globals.
Differential Revision: https://reviews.llvm.org/D28838

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292430 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-18 20:02:31 +00:00
Chandler Carruth
15050a4c1e [PM] The assumption cache is fundamentally designed to be self-updating,
mark it as never invalidated in the new PM.

The old PM already required this to work, and after a discussion with
Hal this seems to really be the only sensible answer. The cache
gracefully degrades as the IR is mutated, and most things which do this
should already be incrementally updating the cache.

This gets rid of a bunch of logic preserving and testing the
invalidation of this analysis.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292039 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-15 00:26:18 +00:00
Simon Pilgrim
79fab99b86 Fix unused variable warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291666 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-11 10:40:33 +00:00
Chandler Carruth
c68d25fb58 [PM] Separate the LoopAnalysisManager from the LoopPassManager and move
the latter to the Transforms library.

While the loop PM uses an analysis to form the IR units, the current
plan is to have the PM itself establish and enforce both loop simplified
form and LCSSA. This would be a layering violation in the analysis
library.

Fundamentally, the idea behind the loop PM is to *transform* loops in
addition to running passes over them, so it really seemed like the most
natural place to sink this was into the transforms library.

We can't just move *everything* because we also have loop analyses that
rely on a subset of the invariants. So this patch splits the the loop
infrastructure into the analysis management that has to be part of the
analysis library, and the transform-aware pass manager.

This also required splitting the loop analyses' printer passes out to
the transforms library, which makes sense to me as running these will
transform the code into LCSSA in theory.

I haven't split the unittest though because testing one component
without the other seems nearly intractable.

Differential Revision: https://reviews.llvm.org/D28452

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291662 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-11 09:43:56 +00:00
Bryant Wong
5b27f1a97f [MemorySSA] Define a restricted upward AccessList splice.
Differential Revision: https://reviews.llvm.org/D26661

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290527 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-25 23:34:07 +00:00
Daniel Jasper
8de3a54f07 Revert @llvm.assume with operator bundles (r289755-r289757)
This creates non-linear behavior in the inliner (see more details in
r289755's commit thread).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290086 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-19 08:22:17 +00:00
Hal Finkel
bffeba468d Remove the AssumptionCache
After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is more computationally efficient, and also we need much less
code...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289756 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-15 03:02:15 +00:00
Amjad Aboud
faaafe58c6 [DebugInfo] Changed DIBuilder::createCompileUnit() to take DIFile instead of FileName and Directory.
This way it will be easier to expand DIFile (e.g., to contain checksum) without the need to modify the createCompileUnit() API.

Reviewers: llvm-commits, rnk

Differential Revision: https://reviews.llvm.org/D27762

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289702 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-14 20:24:54 +00:00
Erik Eckstein
345d21cba1 Make the FunctionComparator of the MergeFunctions pass a stand-alone utility.
This is pure refactoring. NFC.

This change moves the FunctionComparator (together with the GlobalNumberState
utility) in to a separate file so that it can be used by other passes.
For example, the SwiftMergeFunctions pass in the Swift compiler:
https://github.com/apple/swift/blob/master/lib/LLVMPasses/LLVMMergeFunctions.cpp

Details of the change:

*) The big part is just moving code out of MergeFunctions.cpp into FunctionComparator.h/cpp
*) Make FunctionComparator member functions protected (instead of private)
   so that a derived comparator class can use them.

Following refactoring helps to share code between the base FunctionComparator
class and a derived class:

*) Add a beginCompare() function
*) Move some basic function property comparisons into a separate function compareSignature()
*) Do the GEP comparison inside cmpOperations() which now has a new
   needToCmpOperands reference parameter

https://reviews.llvm.org/D25385



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286632 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-11 21:15:13 +00:00
George Burgess IV
fc92168d01 [MemorySSA] Tighten up types to make our API prettier. NFC.
Patch by bryant.

Differential Revision: https://reviews.llvm.org/D26126


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285750 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-01 21:17:46 +00:00
Peter Collingbourne
446d7cc0db Cloning: Also clone global variable attached metadata.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285161 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-26 02:57:33 +00:00
Daniel Berlin
6d6a5e6250 [MSSA] Avoid unnecessary use walks when calling getClobberingMemoryAccess
Summary:
This allows us to mark when uses have been optimized.
This lets us avoid rewalking (IE when people call getClobberingAccess on everything), and also
enables us to later relax the requirement of use optimization during updates with less cost.

Reviewers: george.burgess.iv

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25172

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284771 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-20 20:13:45 +00:00
Victor Leschuk
e69c459a6e DebugInfo: preparation to implement DW_AT_alignment
- Add alignment attribute to DIVariable family
 - Modify bitcode format to match new DIVariable representation
 - Update tests to match these changes (also add bitcode upgrade test)
 - Expect that frontend passes non-zero align value only when it is not default
   (was forcibly aligned by alignas()/_Alignas()/__atribute__(aligned())

Differential Revision: https://reviews.llvm.org/D25073


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284678 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-20 00:13:12 +00:00
Vitaly Buka
6b9bef9d05 [asan] Simplify calculation of stack frame layout extraction calculation of stack description into separate function.
Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D25754

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284547 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-18 23:29:52 +00:00
Vitaly Buka
298a3d2a9a [asan] Append line number to variable name if line is available and in the same file as the function.
PR30498

Reviewers: eugenis

Differential Revision: https://reviews.llvm.org/D25715

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284546 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-18 23:29:41 +00:00
George Burgess IV
e602ff91e3 [MSSA] Allow unittests to use BasicAA when building.
We now build MemorySSA in its ctor, instead of waiting until the user
calls MemorySSA::getWalker. This silently changed our unittests, since
we add BasicAA to AAResults *after* constructing MemorySSA (...but
before calling MemorySSA::getWalker).

None of them broke because we do most of our "did this get optimized
correctly?" tests in .ll files.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283158 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-03 23:12:35 +00:00
Daniel Berlin
c9e7be5af9 Update MemorySSA unittest to account for non-pruned SSA form
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282421 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-26 17:44:31 +00:00
Leny Kholodov
01dd3d966f Formatting with clang-format patch r280700
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280716 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-06 17:03:02 +00:00
Leny Kholodov
d9478f8605 DebugInfo: use strongly typed enum for debug info flags
Use ADT/BitmaskEnum for DINode::DIFlags for the following purposes:

Get rid of unsigned int for flags to avoid problems on platforms with sizeof(int) < 4
Flags are now strongly typed
Patch by: Victor Leschuk <vleschuk@gmail.com>

Differential Revision: https://reviews.llvm.org/D23766



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280700 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-06 10:46:28 +00:00
Mehdi Amini
c581dfbe75 Revert "DebugInfo: use strongly typed enum for debug info flags"
This reverts commit r280686, bots are broken.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280688 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-06 03:26:37 +00:00
Mehdi Amini
454e9fcf45 DebugInfo: use strongly typed enum for debug info flags
Use ADT/BitmaskEnum for DINode::DIFlags for the following purposes:
    * Get rid of unsigned int for flags to avoid problems on platforms with sizeof(int) < 4
    * Flags are now strongly typed

Patch by: Victor Leschuk <vleschuk@gmail.com>

Differential Revision: https://reviews.llvm.org/D23766

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280686 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-06 03:14:06 +00:00
Vitaly Buka
997a485279 [asan] Separate calculation of ShadowBytes from calculating ASanStackFrameLayout
Summary: No functional changes, just refactoring to make D23947 simpler.

Reviewers: eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23954

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279982 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-29 17:41:29 +00:00
Vitaly Buka
939300ca39 [asan] Add support of lifetime poisoning into ComputeASanStackFrameLayout
Summary:
We are going to combine poisoning of red zones and scope poisoning.

PR27453

Reviewers: kcc, eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23623

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279373 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-20 16:48:24 +00:00
Vitaly Buka
b2ae2edf5a Revert "[asan] Add support of lifetime poisoning into ComputeASanStackFrameLayout"
This reverts commit r279020.

Speculative revert in hope to fix asan test on arm.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279332 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-19 22:12:58 +00:00
Vitaly Buka
76e81b28c6 [asan] Add support of lifetime poisoning into ComputeASanStackFrameLayout
Summary:
We are going to combine poisoning of red zones and scope poisoning.

PR27453

Reviewers: kcc, eugenis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D23623

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279020 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-18 00:56:58 +00:00
George Burgess IV
9cdc9dad95 [MSSA] clang-format. NFC.
Didn't want to fold this in with r277640, since it touches bits that
aren't entirely related to r277640.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277641 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-03 19:59:11 +00:00
George Burgess IV
cd112f0139 [MSSA] Add special handling for invariant/constant loads.
This is a follow-up to r277637. It teaches MemorySSA that invariant
loads (and loads of provably constant memory) are always liveOnEntry.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277640 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-03 19:57:02 +00:00
George Burgess IV
265028f005 [MSSA] Fix a caching bug.
This fixes a bug where we'd sometimes cache overly-conservative results
with our walker. This bug was made more obvious by r277480, which makes
our cache far more spotty than it was. Test case is llvm-unit, because
we're likely going to use CachingWalker only for def optimization in the
future.

The bug stems from that there was a place where the walker assumed that
`DefNode.Last` was a valid target to cache to when failing to optimize
phis. This is sometimes incorrect if we have a cache hit. The fix is to
use the thing we *can* assume is a valid target to cache to. :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277559 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-03 01:22:19 +00:00
Daniel Berlin
cdbca76b08 Fix the MemorySSA updating API to enable people to create memory accesses before removing old ones
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277309 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-31 21:08:20 +00:00
Daniel Berlin
9ee47fcd55 Comment fixes to MemorySSA.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277308 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-31 21:08:10 +00:00
Peter Collingbourne
dba9146333 IR: New representation for CFI and virtual call optimization pass metadata.
The bitset metadata currently used in LLVM has a few problems:

1. It has the wrong name. The name "bitset" refers to an implementation
   detail of one use of the metadata (i.e. its original use case, CFI).
   This makes it harder to understand, as the name makes no sense in the
   context of virtual call optimization.

2. It is represented using a global named metadata node, rather than
   being directly associated with a global. This makes it harder to
   manipulate the metadata when rebuilding global variables, summarise it
   as part of ThinLTO and drop unused metadata when associated globals are
   dropped. For this reason, CFI does not currently work correctly when
   both CFI and vcall opt are enabled, as vcall opt needs to rebuild vtable
   globals, and fails to associate metadata with the rebuilt globals. As I
   understand it, the same problem could also affect ASan, which rebuilds
   globals with a red zone.

This patch solves both of those problems in the following way:

1. Rename the metadata to "type metadata". This new name reflects how
   the metadata is currently being used (i.e. to represent type information
   for CFI and vtable opt). The new name is reflected in the name for the
   associated intrinsic (llvm.type.test) and pass (LowerTypeTests).

2. Attach metadata directly to the globals that it pertains to, rather
   than using the "llvm.bitsets" global metadata node as we are doing now.
   This is done using the newly introduced capability to attach
   metadata to global variables (r271348 and r271358).

See also: http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html

Differential Revision: http://reviews.llvm.org/D21053

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273729 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-24 21:21:32 +00:00
Daniel Berlin
11e2958f9b Add MemoryAccess creation and PHI creation APIs to MemorySSA
Reviewers: george.burgess.iv, gberry, hfinkel

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D21463

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273295 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-21 18:39:20 +00:00
George Burgess IV
4c758ff487 [MemorySSA] Clean up unit tests a tiny bit. NFC.
We recently made MemorySSA own the walker it creates. As a part of this,
the MSSA test fixture was changed to have a `Walker*` instead of a
`unique_ptr<Walker>`. So, we no longer need to do `&*Walker` in order to
get a `Walker*`.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273189 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-20 19:13:07 +00:00