Commit Graph

4497 Commits

Author SHA1 Message Date
Sanjoy Das 93f8cc186a Relax constraints for reduction vectorization
Summary:
Gating vectorizing reductions on *all* fastmath flags seems unnecessary;
`reassoc` should be sufficient.

Reviewers: tvvikram, mkuper, kristof.beyls, sdesmalen, Ayal

Reviewed By: sdesmalen

Subscribers: dcaballe, huntergr, jmolloy, mcrosier, jlebar, bixia, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57728

llvm-svn: 355868
2019-03-11 21:36:41 +00:00
Brian Gesiak 4349dc76fa [Utils] Extract EliminateUnreachableBlocks (NFC)
Summary:
Extract the functionality of eliminating unreachable basic blocks
within a function, previously encapsulated within the
-unreachableblockelim pass, and make it available as a function within
BlockUtils.h. No functional change intended other than making the logic
reusable.

Exposing this logic makes it easier to implement
https://reviews.llvm.org/D59068, which fixes coroutines bug
https://bugs.llvm.org/show_bug.cgi?id=40979.

Reviewers: mkazantsev, wmi, davidxl, silvas, davide

Reviewed By: davide

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59069

llvm-svn: 355846
2019-03-11 17:51:57 +00:00
Jeremy Morse 90ede5f4bf [SimplifyCFG] Retain debug info when threading jumps with critical edges
Fixes bug 38023: https://bugs.llvm.org/show_bug.cgi?id=38023

The SimplifyCFG pass will perform jump threading in some cases where
doing so is trivial and would simplify the CFG. When folding a series
of blocks with redundant conditional branches into an unconditional "critical
edge" block, it does not keep the debug location associated with the previous
conditional branch.

This patch fixes the bug described by copying the debug info from the
old conditional branch to the new unconditional branch instruction, and
adds a regression test for the SimplifyCFG pass that covers this case.

Patch by Stephen Tozer!

Differential Revision: https://reviews.llvm.org/D59206

llvm-svn: 355833
2019-03-11 16:23:59 +00:00
Clement Courbet 8e16d73346 [SelectionDAG] Allow the user to specify a memeq function.
Summary:
Right now, when we encounter a string equality check,
e.g. `if (memcmp(a, b, s) == 0)`, we try to expand to a comparison if `s` is a
small compile-time constant, and fall back on calling `memcmp()` else.

This is sub-optimal because memcmp has to compute much more than
equality.

This patch replaces `memcmp(a, b, s) == 0` by `bcmp(a, b, s) == 0` on platforms
that support `bcmp`.

`bcmp` can be made much more efficient than `memcmp` because equality
compare is trivially parallel while lexicographic ordering has a chain
dependency.

Subscribers: fedor.sergeev, jyknight, ckennelly, gchatelet, llvm-commits

Differential Revision: https://reviews.llvm.org/D56593

llvm-svn: 355672
2019-03-08 09:07:45 +00:00
Nick Desaulniers 212c8ac23f [LoopRotate] fix crash encountered with callbr
Summary:
While implementing inlining support for callbr
(https://bugs.llvm.org/show_bug.cgi?id=40722), I hit a crash in Loop
Rotation when trying to build the entire x86 Linux kernel
(drivers/char/random.c). This is a small fix up to r353563.

Test case is drivers/char/random.c (with callbr's inlined), then ran
through creduce, then `opt -opt-bisect-limit=<limit>`, then bugpoint.

Thanks to Craig Topper for immediately spotting the fix, and teaching me
how to fish.

Reviewers: craig.topper, jyknight

Reviewed By: craig.topper

Subscribers: hiraditya, llvm-commits, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58929

llvm-svn: 355564
2019-03-06 23:04:40 +00:00
Chijun Sima 586187639a Make MergeBlockIntoPredecessor conformant to the precondition of calling DTU.applyUpdates
Summary:
It is mentioned in the document of DTU that "It is illegal to submit any update that has already been submitted, i.e., you are supposed not to insert an existent edge or delete a nonexistent edge." It is dangerous to violet this rule because DomTree and PostDomTree occasionally crash on this scenario.

This patch fixes `MergeBlockIntoPredecessor`, making it conformant to this precondition.

Reviewers: kuhar, brzycki, chandlerc

Reviewed By: brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58444

llvm-svn: 355105
2019-02-28 16:47:18 +00:00
Matt Arsenault 65b4ab9921 BreakCriticalEdges: Update PostDominatorTree
llvm-svn: 354673
2019-02-22 15:01:41 +00:00
Roman Tereshin 99a6672bba [LowerSwitch][AMDGPU] Do not handle impossible values
This patch adds LazyValueInfo to LowerSwitch to compute the range of the
value being switched over and reduce the size of the tree LowerSwitch
builds to lower a switch.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D58096

llvm-svn: 354670
2019-02-22 14:33:46 +00:00
Chijun Sima 70e97163e0 [DTU] Refine the interface and logic of applyUpdates
Summary:
This patch separates two semantics of `applyUpdates`:
1. User provides an accurate CFG diff and the dominator tree is updated according to the difference of `the number of edge insertions` and `the number of edge deletions` to infer the status of an edge before and after the update.
2. User provides a sequence of hints. Updates mentioned in this sequence might never happened and even duplicated.

Logic changes:

Previously, removing invalid updates is considered a side-effect of deduplication and is not guaranteed to be reliable. To handle the second semantic, `applyUpdates` does validity checking before deduplication, which can cause updates that have already been applied to be submitted again. Then, different calls to `applyUpdates` might cause unintended consequences, for example,
```
DTU(Lazy) and Edge A->B exists.
1. DTU.applyUpdates({{Delete, A, B}, {Insert, A, B}}) // User expects these 2 updates result in a no-op, but {Insert, A, B} is queued
2. Remove A->B
3. DTU.applyUpdates({{Delete, A, B}}) // DTU cancels this update with {Insert, A, B} mentioned above together (Unintended)
```
But by restricting the precondition that updates of an edge need to be strictly ordered as how CFG changes were made, we can infer the initial status of this edge to resolve this issue.

Interface changes:
The second semantic of `applyUpdates`  is separated to `applyUpdatesPermissive`.
These changes enable DTU(Lazy) to use the first semantic if needed, which is quite useful in `transforms/utils`.

Reviewers: kuhar, brzycki, dmgreen, grosser

Reviewed By: brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58170

llvm-svn: 354669
2019-02-22 13:48:38 +00:00
Chijun Sima f131d6110e [DTU] Deprecate insertEdge*/deleteEdge*
Summary: This patch converts all existing `insertEdge*/deleteEdge*` to `applyUpdates` and marks `insertEdge*/deleteEdge*` as deprecated.

Reviewers: kuhar, brzycki

Reviewed By: kuhar, brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58443

llvm-svn: 354652
2019-02-22 05:41:43 +00:00
Alina Sbirlea 97468e9282 [MemorySSA & LoopPassManager] Update MemorySSA in formDedicatedExitBlocks.
MemorySSA is now updated when forming dedicated exit blocks.
Resolves PR40037.

llvm-svn: 354623
2019-02-21 21:13:34 +00:00
Philip Reames 79d5e16f51 [GVN] Small tweaks to comments, style, and missed vector handling
Noticed these while doing a final sweep of the code to make sure I hadn't missed anything in my last couple of patches.  The (minor) missed optimization was noticed because of the stylistic fix to avoid an overly specific cast.

llvm-svn: 354412
2019-02-20 00:31:28 +00:00
Philip Reames a259dc3263 [GVN] Fix last crasher w/non-integral pointers
Same case as for memset and memcpy, but this time for clobbering stores and loads.  We still can't allow coercion to or from non-integrals, regardless of the transform.

Now that I'm done the whole little sequence, it seems apparent that we'd entirely missed reasoning about clobbers in the original GVN support for non-integral pointers.

My appologies, I thought we'd upstreamed all of this, but it turns out we were still carrying a downstream hack which hid all of these issues.  My chanks to Cherry Zhang for helping debug.

llvm-svn: 354407
2019-02-20 00:15:54 +00:00
Philip Reames 952d234d00 [GVN] Fix a crash bug w/non-integral pointers and memtransfers
Problem is very similiar to the one fixed for memsets in r354399, we try to coerce a value to non-integral type, and then crash while try to do so.  Since we shouldn't be doing such coercions to start with, easy fix.  From inspection, I see two other cases which look to be similiar and will follow up with most test cases and fixes if confirmed.

llvm-svn: 354403
2019-02-19 23:49:38 +00:00
Philip Reames 322eb7660e [GVN] Fix a non-integral pointer bug w/vector types
GVN generally doesn't forward structs or array types, but it *will* forward vector types to non-vectors and vice versa.  As demonstrated in tests, we need to inhibit the same set of transforms for vector of non-integral pointers as for non-integral pointers themselves.

llvm-svn: 354401
2019-02-19 23:19:51 +00:00
Philip Reames 92756a80e7 [GVN] Fix a crash bug around non-integral pointers
If we encountered a location where we tried to forward the value of a memset to a load of a non-integral pointer, we crashed.  Such a forward is not legal in general, but we can forward null pointers.  Test for both cases are included.

llvm-svn: 354399
2019-02-19 23:07:15 +00:00
Vedant Kumar 5f5cac3ae2 [CodeExtractor] Do not lift lifetime.end markers for region inputs
If a lifetime.end marker occurs along one path through the extraction
region, but not another, then it's still incorrect to lift the marker,
because there is some path through the extracted function which would
ordinarily not reach the marker. If the call to the extracted function
is in a loop, unrolling can cause inputs to the function to become
optimized out as undef after the first iteration.

To prevent incorrect stack slot merging in the calling function, it
should be sufficient to lift lifetime.start markers for region inputs.
I've tested this theory out by doing a stage2 check-all with randomized
splitting enabled.

This is a follow-up to r353973, and there's additional context for this
change in https://reviews.llvm.org/D57834.

rdar://47896986

Differential Revision: https://reviews.llvm.org/D58253

llvm-svn: 354159
2019-02-15 18:46:58 +00:00
Max Kazantsev 73db5c137a [NFC] Tweak SplitBlockAndInsertIfThen to use existing ThenBlock
llvm-svn: 354107
2019-02-15 08:18:00 +00:00
Florian Hahn 6ab83b7db6 [LoopUnrollPeel] Add case where we should forget the peeled loop from SCEV.
The test case requires the peeled loop to be forgotten after peeling,
even though it does not have a parent. When called via the unroller,
SE->forgetTopmostLoop is also called, so the test case would also pass
without any SCEV invalidation, but peelLoop is exposed as utility
function. Also, in the test case, simplifyLoop will make changes,
removing the loop from SCEV, but it is better to not rely on this
behavior.

Reviewers: sanjoy, mkazantsev

Reviewed By: mkazantsev

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58192

llvm-svn: 354031
2019-02-14 13:59:39 +00:00
Vedant Kumar 4b0cc9a7c8 [CodeExtractor] Only lift lifetime markers present in the extraction region
When CodeExtractor finds liftime markers referencing inputs to the
extraction region, it lifts these markers out of the region and inserts
them around the call to the extracted function (see r350420, PR39671).

However, it should *only* lift lifetime markers that are actually
present in the extraction region. I.e., if a start marker is present in
the extraction region but a corresponding end marker isn't (or vice
versa), only the start marker (or end marker, resp.) should be lifted.

Differential Revision: https://reviews.llvm.org/D57834

llvm-svn: 353973
2019-02-13 19:53:38 +00:00
Jeremy Morse b33a5c7347 [DebugInfo] Don't salvage load operations (PR40628).
Salvaging a redundant load instruction into a debug expression hides a
memory read from optimisation passes. Passes that alter memory behaviour
(such as LICM promoting memory to a register) aren't aware of these debug
memory reads and leave them unaltered, making the debug variable location
point somewhere unsafe.

Teaching passes to know about these debug memory reads would be challenging
and probably incomplete. Finding dbg.value instructions that need to be fixed
would likely be computationally expensive too, as more analysis would be
required. It's better to not generate debug-memory-reads instead, alas.

Changed tests:
 * DeadStoreElim: test for salvaging of intermediate operations contributing
   to the dead store, instead of salvaging of the redundant load,
 * GVN: remove debuginfo behaviour checks completely, this behaviour is still
   covered by other tests,
 * InstCombine: don't test for salvaged loads, we're removing that behaviour.

Differential Revision: https://reviews.llvm.org/D57962

llvm-svn: 353824
2019-02-12 10:54:30 +00:00
Max Kazantsev 20b9189975 [NFC] Rename DontDeleteUselessPHIs --> KeepOneInputPHIs
llvm-svn: 353801
2019-02-12 07:09:29 +00:00
Max Kazantsev 0686d1ae41 [NFC] Add parameter for keeping one-input Phis in DeleteDeadBlock(s)
llvm-svn: 353799
2019-02-12 06:14:27 +00:00
Chandler Carruth 751d95fb9b [CallSite removal] Migrate ConstantFolding APIs and implementation to
`CallBase`.

Users have been updated. You can see how to update any out-of-tree
usages: pass `cast<CallBase>(CS.getInstruction())`.

llvm-svn: 353661
2019-02-11 07:51:44 +00:00
Chandler Carruth 3160734af1 [CallSite removal] Migrate the statepoint GC infrastructure to use the
`CallBase` class rather than `CallSite` wrappers.

I pushed this change down through most of the statepoint infrastructure,
completely removing the use of CallSite where I could reasonably do so.
I ended up making a couple of cut-points: generic call handling
(instcombine, TLI, SDAG). As soon as it hit truly generic handling with
users outside the immediate code, I simply transitioned into or out of
a `CallSite` to make this a reasonable sized chunk.

Differential Revision: https://reviews.llvm.org/D56122

llvm-svn: 353660
2019-02-11 07:42:30 +00:00
Fangrui Song 709a3e7488 [Local] Delete a redundant check. NFC
isInstructionTriviallyDead also performs the use_empty() check.

llvm-svn: 353637
2019-02-10 09:25:56 +00:00
Craig Topper 784929d045 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

llvm-svn: 353563
2019-02-08 20:48:56 +00:00
Vedant Kumar 0e5dd512aa [CodeExtractor] Restore outputs after creating exit stubs
When CodeExtractor saves the result of InvokeInst at the first insertion
point of the 'normal destination' basic block, this block can be omitted
in the outlined region, so store is placed outside of the function. The
suggested solution is to process saving outputs after creating exit
stubs for new function, and stores will be placed in that blocks before
return in this case.

Patch by Sergei Kachkov!

Fixes llvm.org/PR40455.

Differential Revision: https://reviews.llvm.org/D57919

llvm-svn: 353562
2019-02-08 20:48:04 +00:00
Carlos Alberto Enciso 08dc50f2fb [DWARF] LLVM ERROR: Broken function found, while removing Debug Intrinsics.
Check that when SimplifyCFG is flattening a 'br', all their debug intrinsic instructions are removed, including any dbg.label referencing a label associated with the basic blocks being removed.

Differential Revision: https://reviews.llvm.org/D57444

llvm-svn: 353511
2019-02-08 10:57:26 +00:00
Sergey Dmitriev 807960e6ef [CodeExtractor] Update function's assumption cache after extracting blocks from it
Summary: Assumption cache's self-updating mechanism does not correctly handle the case when blocks are extracted from the function by the CodeExtractor. As a result function's assumption cache may have stale references to the llvm.assume calls that were moved to the outlined function. This patch fixes this problem by removing extracted llvm.assume calls from the function’s assumption cache.

Reviewers: hfinkel, vsk, fhahn, davidxl, sanjoy

Reviewed By: hfinkel, vsk

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57215

llvm-svn: 353500
2019-02-08 06:55:18 +00:00
Alina Sbirlea 6cba96ed52 [LICM/MSSA] Add promotion to scalars by building an AliasSetTracker with MemorySSA.
Summary:
Experimentally we found that promotion to scalars carries less benefits
than sinking and hoisting in LICM. When using MemorySSA, we build an
AliasSetTracker on demand in order to reuse the current infrastructure.
We only build it if less than AccessCapForMSSAPromotion exist in the
loop, a cap that is by default set to 250. This value ensures there are
no runtime regressions, and there are small compile time gains for
pathological cases. A much lower value (20) was found to yield a single
regression in the llvm-test-suite and much higher benefits for compile
times. Conservatively we set the current cap to a high value, but we will
explore lowering it when MemorySSA is enabled by default.

Reviewers: sanjoy, chandlerc

Subscribers: nemanjai, jlebar, Prazek, george.burgess.iv, jfb, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D56625

llvm-svn: 353339
2019-02-06 20:25:17 +00:00
Max Kazantsev 36b392cbe4 [NFC] Factor out detatchment of dead blocks from their erasing
llvm-svn: 353277
2019-02-06 07:56:36 +00:00
Max Kazantsev 0d7ad3c9a3 [NFC] Revert rL353274
llvm-svn: 353275
2019-02-06 06:33:02 +00:00
Max Kazantsev 61e6ffc398 [NFC] Extend API of DeleteDeadBlock(s) to collect updates without DTU
llvm-svn: 353274
2019-02-06 06:00:02 +00:00
Max Kazantsev bad4db8b1a [NFC] Replace readonly SmallVectorImpl with ArrayRef
llvm-svn: 353273
2019-02-06 05:40:31 +00:00
Richard Trieu 5f436fc57a Move DomTreeUpdater from IR to Analysis
DomTreeUpdater depends on headers from Analysis, but is in IR.  This is a
layering violation since Analysis depends on IR.  Relocate this code from IR
to Analysis to fix the layering violation.

llvm-svn: 353265
2019-02-06 02:52:52 +00:00
Jeremy Morse 84ca706be1 [DebugInfo][NFCI] Split salvageDebugInfo into helper functions
Some use cases are appearing where salvaging is needed that does not
correspond to an instruction being deleted -- for example an instruction
being sunk, or a Value not being available in a block being isel'd.

Enable more fine grained control over how salavging occurs by splitting
the logic into helper functions, separating things that are specific to
working on DbgVariableIntrinsics from those specific to interpreting IR
and building DIExpressions.

Differential Revision: https://reviews.llvm.org/D57696

llvm-svn: 353156
2019-02-05 11:11:28 +00:00
Michael Kruse 70560a0a2c [WarnMissedTransforms] Do not warn about already vectorized loops.
LoopVectorize adds llvm.loop.isvectorized, but leaves
llvm.loop.vectorize.enable. Do not consider such a loop for user-forced
vectorization since vectorization already happened -- by prioritizing
llvm.loop.isvectorized except for TM_SuppressedByUser.

Fixes http://llvm.org/PR40546

Differential Revision: https://reviews.llvm.org/D57542

llvm-svn: 353082
2019-02-04 19:55:59 +00:00
Florian Hahn dd2ef0af46 [LCSSA] Handle case with single new PHI faster.
If there is only a single available value, all uses must be dominated by
the single value and there is no need to search for a reaching
definition.

This drastically speeds up LCSSA in some cases. For the test case
from PR37202, it speeds up LCSSA construction by 4 times.

Time-passes without this patch for test case from PR37202:

    Total Execution Time: 29.9285 seconds (29.9276 wall clock)

    ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
    5.2786 ( 17.7%)   0.0021 (  1.2%)   5.2806 ( 17.6%)   5.2808 ( 17.6%)  Unswitch loops
    4.3739 ( 14.7%)   0.0303 ( 18.1%)   4.4042 ( 14.7%)   4.4042 ( 14.7%)  Loop-Closed SSA Form Pass
    4.2658 ( 14.3%)   0.0192 ( 11.5%)   4.2850 ( 14.3%)   4.2851 ( 14.3%)  Loop-Closed SSA Form Pass #2
    2.2307 (  7.5%)   0.0013 (  0.8%)   2.2320 (  7.5%)   2.2318 (  7.5%)  Loop Invariant Code Motion
    2.0888 (  7.0%)   0.0012 (  0.7%)   2.0900 (  7.0%)   2.0897 (  7.0%)  Unroll loops
    1.6761 (  5.6%)   0.0013 (  0.8%)   1.6774 (  5.6%)   1.6774 (  5.6%)  Value Propagation
    1.3686 (  4.6%)   0.0029 (  1.8%)   1.3716 (  4.6%)   1.3714 (  4.6%)  Induction Variable Simplification
    1.1457 (  3.8%)   0.0010 (  0.6%)   1.1468 (  3.8%)   1.1468 (  3.8%)  Loop-Closed SSA Form Pass #4
    1.1384 (  3.8%)   0.0005 (  0.3%)   1.1389 (  3.8%)   1.1389 (  3.8%)  Loop-Closed SSA Form Pass #6
    1.1360 (  3.8%)   0.0027 (  1.6%)   1.1387 (  3.8%)   1.1387 (  3.8%)  Loop-Closed SSA Form Pass #5
    1.1331 (  3.8%)   0.0010 (  0.6%)   1.1341 (  3.8%)   1.1340 (  3.8%)  Loop-Closed SSA Form Pass #3

Time passes with this patch

  Total Execution Time: 19.2802 seconds (19.2813 wall clock)

   ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
   4.4234 ( 23.2%)   0.0038 (  2.0%)   4.4272 ( 23.0%)   4.4273 ( 23.0%)  Unswitch loops
   2.3828 ( 12.5%)   0.0020 (  1.1%)   2.3848 ( 12.4%)   2.3847 ( 12.4%)  Unroll loops
   1.8714 (  9.8%)   0.0020 (  1.1%)   1.8734 (  9.7%)   1.8735 (  9.7%)  Loop Invariant Code Motion
   1.7973 (  9.4%)   0.0022 (  1.2%)   1.7995 (  9.3%)   1.8003 (  9.3%)  Value Propagation
   1.4010 (  7.3%)   0.0033 (  1.8%)   1.4043 (  7.3%)   1.4044 (  7.3%)  Induction Variable Simplification
   0.9978 (  5.2%)   0.0244 ( 13.1%)   1.0222 (  5.3%)   1.0224 (  5.3%)  Loop-Closed SSA Form Pass #2
   0.9611 (  5.0%)   0.0257 ( 13.8%)   0.9868 (  5.1%)   0.9868 (  5.1%)  Loop-Closed SSA Form Pass
   0.5856 (  3.1%)   0.0015 (  0.8%)   0.5871 (  3.0%)   0.5869 (  3.0%)  Unroll loops #2
   0.4132 (  2.2%)   0.0012 (  0.7%)   0.4145 (  2.1%)   0.4143 (  2.1%)  Loop Invariant Code Motion #3

Reviewers: efriedma, davide, mzolotukhin

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D57033

llvm-svn: 352960
2019-02-02 15:26:05 +00:00
Florian Hahn 509b48a64a [LCSSA] Add expensive verification of LCSSA form for sub-loops.
This assertion makes sure all sub-loops are in LCSSA form before
bringing their parent in LCSSA form. This precondition was added to
formLCSSA in D56848.

Reviewers: davide, efriedma, mzolotukhin

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D56921

llvm-svn: 352958
2019-02-02 14:42:27 +00:00
James Y Knight 291f791ef1 [opaque pointer types] Pass function type for CallBase::setCalledFunction.
Differential Revision: https://reviews.llvm.org/D57174

llvm-svn: 352914
2019-02-01 20:44:54 +00:00
James Y Knight 7716075a17 [opaque pointer types] Pass value type to GetElementPtr creation.
This cleans up all GetElementPtr creation in LLVM to explicitly pass a
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57173

llvm-svn: 352913
2019-02-01 20:44:47 +00:00
James Y Knight 14359ef1b6 [opaque pointer types] Pass value type to LoadInst creation.
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57172

llvm-svn: 352911
2019-02-01 20:44:24 +00:00
James Y Knight d9e85a0861 [opaque pointer types] Pass function types to InvokeInst creation.
This cleans up all InvokeInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57171

llvm-svn: 352910
2019-02-01 20:43:34 +00:00
James Y Knight 7976eb5838 [opaque pointer types] Pass function types to CallInst creation.
This cleans up all CallInst creation in LLVM to explicitly pass a
function type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57170

llvm-svn: 352909
2019-02-01 20:43:25 +00:00
James Y Knight 13680223b9 [opaque pointer types] Add a FunctionCallee wrapper type, and use it.
Recommit r352791 after tweaking DerivedTypes.h slightly, so that gcc
doesn't choke on it, hopefully.

Original Message:
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352827
2019-02-01 02:28:03 +00:00
James Y Knight fadf25068e Revert "[opaque pointer types] Add a FunctionCallee wrapper type, and use it."
This reverts commit f47d6b38c7 (r352791).

Seems to run into compilation failures with GCC (but not clang, where
I tested it). Reverting while I investigate.

llvm-svn: 352800
2019-01-31 21:51:58 +00:00
James Y Knight f47d6b38c7 [opaque pointer types] Add a FunctionCallee wrapper type, and use it.
The FunctionCallee type is effectively a {FunctionType*,Value*} pair,
and is a useful convenience to enable code to continue passing the
result of getOrInsertFunction() through to EmitCall, even once pointer
types lose their pointee-type.

Then:
- update the CallInst/InvokeInst instruction creation functions to
  take a Callee,
- modify getOrInsertFunction to return FunctionCallee, and
- update all callers appropriately.

One area of particular note is the change to the sanitizer
code. Previously, they had been casting the result of
`getOrInsertFunction` to a `Function*` via
`checkSanitizerInterfaceFunction`, and storing that. That would report
an error if someone had already inserted a function declaraction with
a mismatching signature.

However, in general, LLVM allows for such mismatches, as
`getOrInsertFunction` will automatically insert a bitcast if
needed. As part of this cleanup, cause the sanitizer code to do the
same. (It will call its functions using the expected signature,
however they may have been declared.)

Finally, in a small number of locations, callers of
`getOrInsertFunction` actually were expecting/requiring that a brand
new function was being created. In such cases, I've switched them to
Function::Create instead.

Differential Revision: https://reviews.llvm.org/D57315

llvm-svn: 352791
2019-01-31 20:35:56 +00:00
Teresa Johnson f59242e5ff Recommit "[ThinLTO] Rename COMDATs for COFF when promoting/renaming COMDAT leader"
Recommit of r352763 with fix for use after free.

llvm-svn: 352770
2019-01-31 17:18:11 +00:00
Teresa Johnson 4877715ee6 Revert "[ThinLTO] Rename COMDATs for COFF when promoting/renaming COMDAT leader"
This reverts commit r352763.

Causing a couple bot failures, root cause pointed to by sanitizer bot:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/28909/steps/annotate/logs/stdio

Use after free. I understand the issue but will revert and test with fix
before recommitting.

llvm-svn: 352768
2019-01-31 16:46:14 +00:00
Teresa Johnson 992b53fd16 [ThinLTO] Rename COMDATs for COFF when promoting/renaming COMDAT leader
Summary:
COFF requires that COMDAT name match that of the leader. When we promote
and rename an internal leader in ThinLTO due to an import, ensure we
subsequently rename the associated COMDAT. Similar to D31963 which did
this during ThinLTO module splitting.

Fixes PR40414.

Reviewers: pcc, inglorion

Subscribers: mehdi_amini, dexonsmith, dmajor, llvm-commits

Differential Revision: https://reviews.llvm.org/D57395

llvm-svn: 352763
2019-01-31 16:00:15 +00:00
Alina Sbirlea f9027e554a Check bool attribute value in getOptionalBoolLoopAttribute.
Summary:
Check the bool value of the attribute in getOptionalBoolLoopAttribute
not just its existance.
Eliminates the warning noise generated when vectorization is explicitly disabled.

Reviewers: Meinersbur, hfinkel, dmgreen

Subscribers: jlebar, sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D57260

llvm-svn: 352555
2019-01-29 22:33:20 +00:00
Vedant Kumar 1c3694a4d4 [CodeExtractor] Add support for the `swifterror` attribute
When passing a `swifterror` argument or alloca as an input to an
extraction region, mark the input parameter `swifterror`.

llvm-svn: 352408
2019-01-28 19:13:37 +00:00
Julian Lettner b62e9dc46b Revert "[Sanitizers] UBSan unreachable incompatible with ASan in the presence of `noreturn` calls"
This reverts commit cea84ab93a.

llvm-svn: 352069
2019-01-24 18:04:21 +00:00
Julian Lettner cea84ab93a [Sanitizers] UBSan unreachable incompatible with ASan in the presence of `noreturn` calls
Summary:
UBSan wants to detect when unreachable code is actually reached, so it
adds instrumentation before every `unreachable` instruction. However,
the optimizer will remove code after calls to functions marked with
`noreturn`. To avoid this UBSan removes `noreturn` from both the call
instruction as well as from the function itself. Unfortunately, ASan
relies on this annotation to unpoison the stack by inserting calls to
`_asan_handle_no_return` before `noreturn` functions. This is important
for functions that do not return but access the the stack memory, e.g.,
unwinder functions *like* `longjmp` (`longjmp` itself is actually
"double-proofed" via its interceptor). The result is that when ASan and
UBSan are combined, the `noreturn` attributes are missing and ASan
cannot unpoison the stack, so it has false positives when stack
unwinding is used.

Changes:
  # UBSan now adds the `expect_noreturn` attribute whenever it removes
    the `noreturn` attribute from a function
  # ASan additionally checks for the presence of this attribute

Generated code:
```
call void @__asan_handle_no_return    // Additionally inserted to avoid false positives
call void @longjmp
call void @__asan_handle_no_return
call void @__ubsan_handle_builtin_unreachable
unreachable
```

The second call to `__asan_handle_no_return` is redundant. This will be
cleaned up in a follow-up patch.

rdar://problem/40723397

Reviewers: delcypher, eugenis

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D56624

llvm-svn: 352003
2019-01-24 01:06:19 +00:00
David Callahan d2eeb2516d Update entry count for cold calls
Summary:
Profile sample files include the number of times each entry or inlined
call site is sampled. This is translated into the entry count metadta
on functions.

When sample data is being read, if a call site that was inlined
in the sample program is considered cold and not inlined, then
the entry count of the out-of-line functions does not reflect
the current compilation.

In this patch, we note call sites where the function was not inlined
and as a last action of the sample profile loading, we update the
called function's entry count to reflect the calls from these
call sites which are not included in the profile file.

Reviewers: danielcdh, wmi, Kader, modocache

Reviewed By: wmi

Subscribers: davidxl, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D52845

llvm-svn: 352001
2019-01-24 00:55:23 +00:00
Mircea Trofin ec02630278 [llvm] Clarify responsiblity of some of DILocation discriminator APIs
Summary:
Renamed setBaseDiscriminator to cloneWithBaseDiscriminator, to match
similar APIs. Also changed its behavior to copy over the other
discriminator components, instead of eliding them.

Renamed cloneWithDuplicationFactor to
cloneByMultiplyingDuplicationFactor, which more closely matches what
this API does.

Reviewers: dblaikie, wmi

Reviewed By: dblaikie

Subscribers: zzheng, llvm-commits

Differential Revision: https://reviews.llvm.org/D56220

llvm-svn: 351996
2019-01-24 00:10:25 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Vedant Kumar 17d9f14bff [CodeExtractor] Emit lifetime markers around reloads of outputs
CodeExtractor permits extracting a region of blocks from a function even
when values defined within the region are used outside of it.

This is typically done by creating an alloca in the original function
and reloading the alloca after a call to the extracted function.

Wrap the reload in lifetime start/end markers to promote stack coloring.

Suggested by Sergei Kachkov!

Differential Revision: https://reviews.llvm.org/D56045

llvm-svn: 351621
2019-01-19 02:37:59 +00:00
Florian Hahn be7cbe3f70 [LCSSA] Skip blocks in sub-loops when scanning for uses.
Summary:
Scanning blocks in sub-loops for uses is unnecessary, as they were
already handled while dealing with the containing sub-loop.

This speeds up LCSSA for highly nested loops. For the test case in PR37202, it
halves the time spent in LCSSA. In cases were we won't be able to skip
any blocks, the additional lookup should be negligible.

Time-passes without this patch for test case from PR37202:

  Total Execution Time: 48.5505 seconds (48.5511 wall clock)

   ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
  10.0822 ( 21.0%)   0.1406 ( 27.0%)  10.2228 ( 21.1%)  10.2228 ( 21.1%)  Loop-Closed SSA Form Pass
  10.0417 ( 20.9%)   0.1467 ( 28.2%)  10.1884 ( 21.0%)  10.1890 ( 21.0%)  Loop-Closed SSA Form Pass #2
   4.2703 (  8.9%)   0.0040 (  0.8%)   4.2742 (  8.8%)   4.2742 (  8.8%)  Unswitch loops
   2.7376 (  5.7%)   0.0229 (  4.4%)   2.7605 (  5.7%)   2.7611 (  5.7%)  Loop-Closed SSA Form Pass #5
   2.7332 (  5.7%)   0.0214 (  4.1%)   2.7546 (  5.7%)   2.7546 (  5.7%)  Loop-Closed SSA Form Pass #3
   2.7088 (  5.6%)   0.0230 (  4.4%)   2.7319 (  5.6%)   2.7324 (  5.6%)  Loop-Closed SSA Form Pass #4
   2.6855 (  5.6%)   0.0236 (  4.5%)   2.7091 (  5.6%)   2.7090 (  5.6%)  Loop-Closed SSA Form Pass #6
   2.1648 (  4.5%)   0.0018 (  0.4%)   2.1666 (  4.5%)   2.1664 (  4.5%)  Unroll loops
   1.8371 (  3.8%)   0.0009 (  0.2%)   1.8379 (  3.8%)   1.8380 (  3.8%)  Value Propagation
   1.8149 (  3.8%)   0.0021 (  0.4%)   1.8170 (  3.7%)   1.8169 (  3.7%)  Loop Invariant Code Motion
   1.6755 (  3.5%)   0.0226 (  4.3%)   1.6981 (  3.5%)   1.6980 (  3.5%)  Loop-Closed SSA Form Pass #7

Time-passes with this patch

  Total Execution Time: 29.9285 seconds (29.9276 wall clock)

   ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
   5.2786 ( 17.7%)   0.0021 (  1.2%)   5.2806 ( 17.6%)   5.2808 ( 17.6%)  Unswitch loops
   4.3739 ( 14.7%)   0.0303 ( 18.1%)   4.4042 ( 14.7%)   4.4042 ( 14.7%)  Loop-Closed SSA Form Pass
   4.2658 ( 14.3%)   0.0192 ( 11.5%)   4.2850 ( 14.3%)   4.2851 ( 14.3%)  Loop-Closed SSA Form Pass #2
   2.2307 (  7.5%)   0.0013 (  0.8%)   2.2320 (  7.5%)   2.2318 (  7.5%)  Loop Invariant Code Motion
   2.0888 (  7.0%)   0.0012 (  0.7%)   2.0900 (  7.0%)   2.0897 (  7.0%)  Unroll loops
   1.6761 (  5.6%)   0.0013 (  0.8%)   1.6774 (  5.6%)   1.6774 (  5.6%)  Value Propagation
   1.3686 (  4.6%)   0.0029 (  1.8%)   1.3716 (  4.6%)   1.3714 (  4.6%)  Induction Variable Simplification
   1.1457 (  3.8%)   0.0010 (  0.6%)   1.1468 (  3.8%)   1.1468 (  3.8%)  Loop-Closed SSA Form Pass #4
   1.1384 (  3.8%)   0.0005 (  0.3%)   1.1389 (  3.8%)   1.1389 (  3.8%)  Loop-Closed SSA Form Pass #6
   1.1360 (  3.8%)   0.0027 (  1.6%)   1.1387 (  3.8%)   1.1387 (  3.8%)  Loop-Closed SSA Form Pass #5
   1.1331 (  3.8%)   0.0010 (  0.6%)   1.1341 (  3.8%)   1.1340 (  3.8%)  Loop-Closed SSA Form Pass #3

Reviewers: davide, efriedma, mzolotukhin

Reviewed By: davide, efriedma

Subscribers: hiraditya, dmgreen, llvm-commits

Differential Revision: https://reviews.llvm.org/D56848

llvm-svn: 351567
2019-01-18 17:36:22 +00:00
Vedant Kumar e21ab22115 [FunctionComparator] Consider tail call kinds
Essentially, do not treat `call` and `musttail call` as the same thing.

As a drive-by, fold CallInst and InvokeInst handling together using the
CallSite helper.

Differential Revision: https://reviews.llvm.org/D56815

llvm-svn: 351405
2019-01-17 00:29:14 +00:00
Philip Pfaffe 685c76d7a3 [NewPM][TSan] Reiterate the TSan port
Summary:
Second iteration of D56433 which got reverted in rL350719. The problem
in the previous version was that we dropped the thunk calling the tsan init
function. The new version keeps the thunk which should appease dyld, but is not
actually OK wrt. the current semantics of function passes. Hence, add a
helper to insert the functions only on the first time. The helper
allows hooking into the insertion to be able to append them to the
global ctors list.

Reviewers: chandlerc, vitalybuka, fedor.sergeev, leonardchan

Subscribers: hiraditya, bollu, llvm-commits

Differential Revision: https://reviews.llvm.org/D56538

llvm-svn: 351314
2019-01-16 09:28:01 +00:00
David Callahan d129d3e93f treat invoke like call
Summary:
InvokeInst should be treated like CallInst and
assigned a separate discriminator. This is particularly
import when an Invoke is converted to a Call
during compilation and so can invalidate sample profile
data collected wtih different link time optimizations

Reviewers: twoh, Kader, danielcdh, wmi

Reviewed By: wmi

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D56491

llvm-svn: 351251
2019-01-15 21:26:51 +00:00
Max Kazantsev a78dc4d6c8 [NFC] Move some functions to LoopUtils
llvm-svn: 351179
2019-01-15 09:51:34 +00:00
Jeremy Morse f216da7ee0 [DebugInfo] Remove un-necessary logic from HoistThenElseCodeToIf
Following PR39807, the way in which SimplifyCFG hoists common code on
branch paths was fixed in r347782. However this left extra code hanging
around HoistThenElseCodeToIf that wasn't necessary and needlessly
complicated matters -- we no longer need to look up through the 'if'
basic block to find a location for hoisted 'select' insts, we can instead
use the location chosen by applyMergedLocation.

This patch deletes that extra logic, and updates a regression test to
reflect the new logic (selects get the merged location, not a previous
insts location).

Differential Revision: https://reviews.llvm.org/D55272

llvm-svn: 351058
2019-01-14 12:13:12 +00:00
Max Kazantsev 1f73310e1e [BasicBlockUtils] Generalize DeleteDeadBlock to deal with multiple dead blocks
Utility function `DeleteDeadBlock` expects that all predecessors of a block being
deleted are already deleted, with the exception of single-block loop. It makes it
hard to use for deletion of a set of blocks that may contain cyclic dependencies.
The is no correct order of invocations of this function that does not produce
dangling pointers on already deleted blocks.

This patch introduces a generalized version of this function `DeleteDeadBlocks`
that allows us to remove multiple blocks at once, even if there are cycles among
them. The only requirement is that no block being deleted should have a predecessor
that is not being deleted. 

The logic of `DeleteDeadBlocks` is following:
  for each block
    create relevant DT updates;
    remove all instructions (replace with undef if needed);
    replace terminator with unreacheable;
  apply DT updates;
  for each block
    delete block;

Therefore, `DeleteDeadBlock` becomes a particular case of
the general algorithm called for a single block.

Differential Revision: https://reviews.llvm.org/D56120
Reviewed By: skatkov

llvm-svn: 351045
2019-01-14 10:26:26 +00:00
Eli Friedman d4e7a0d83c [SimplifyLibCalls] Fix memchr expansion for constant strings.
The C standard says "The memchr function locates the first
occurrence of c (converted to an unsigned char)[...]".  The expansion
was missing the conversion to unsigned char.

Fixes https://bugs.llvm.org/show_bug.cgi?id=39041 .

Differential Revision: https://reviews.llvm.org/D55947

llvm-svn: 350775
2019-01-09 23:39:26 +00:00
Anna Thomas 2dfa412efe [UnrollRuntime] Fix domTree failures in multiexit unrolling
Summary:
This fixes the IDom for exit blocks and all blocks reachable from the exit blocks, when runtime unrolling under multiexit/exiting case.
We initially had a restrictive check that the IDom is only updated when
it is the header of the loop.
However, we also need to update the IDom to the correct one when the
IDom is any block within the original loop. See added test cases (which
fail dom tree verification without the patch).

Reviewers: reames, mzolotukhin, mkazantsev, hfinkel

Reviewed by: brzycki, kuhar

Subscribers: zzheng, dmgreen, llvm-commits

Differential Revision: https://reviews.llvm.org/D56284

llvm-svn: 350640
2019-01-08 17:16:25 +00:00
Chandler Carruth 363ac68374 [CallSite removal] Migrate all Alias Analysis APIs to use the newly
minted `CallBase` class instead of the `CallSite` wrapper.

This moves the largest interwoven collection of APIs that traffic in
`CallSite`s. While a handful of these could have been migrated with
a minorly more shallow migration by converting from a `CallSite` to
a `CallBase`, it hardly seemed worth it. Most of the APIs needed to
migrate together because of the complex interplay of AA APIs and the
fact that converting from a `CallBase` to a `CallSite` isn't free in its
current implementation.

Out of tree users of these APIs can fairly reliably migrate with some
combination of `.getInstruction()` on the `CallSite` instance and
casting the resulting pointer. The most generic form will look like `CS`
-> `cast_or_null<CallBase>(CS.getInstruction())` but in most cases there
is a more elegant migration. Hopefully, this migrates enough APIs for
users to fully move from `CallSite` to the base class. All of the
in-tree users were easily migrated in that fashion.

Thanks for the review from Saleem!

Differential Revision: https://reviews.llvm.org/D55641

llvm-svn: 350503
2019-01-07 05:42:51 +00:00
Teresa Johnson 853b962416 [ThinLTO] Handle chains of aliases
At -O0, globalopt is not run during the compile step, and we can have a
chain of an alias having an immediate aliasee of another alias. The
summaries are constructed assuming aliases in a canonical form
(flattened chains), and as a result only the base object but no
intermediate aliases were preserved.

Fix by adding a pass that canonicalize aliases, which ensures each
alias is a direct alias of the base object.

Reviewers: pcc, davidxl

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

Differential Revision: https://reviews.llvm.org/D54507

llvm-svn: 350423
2019-01-04 19:04:54 +00:00
Vedant Kumar a1778df474 [CodeExtractor] Do not extract unsafe lifetime markers
Lifetime markers which reference inputs to the extraction region are not
safe to extract. Example ('rhs' will be extracted):

```
               entry:
              +------------+
              | x = alloca |
              | y = alloca |
              +------------+
             /              \
   lhs:                      rhs:
  +-------------------+     +-------------------+
  | lifetime_start(x) |     | lifetime_start(x) |
  | use(x)            |     | lifetime_start(y) |
  | lifetime_end(x)   |     | use(x, y)         |
  | lifetime_start(y) |     | lifetime_end(y)   |
  | use(y)            |     | lifetime_end(x)   |
  | lifetime_end(y)   |     +-------------------+
  +-------------------+
```

Prior to extraction, the stack coloring pass sees that the slots for 'x'
and 'y' are in-use at the same time. After extraction, the coloring pass
infers that 'x' and 'y' are *not* in-use concurrently, because markers
from 'rhs' are no longer available to help decide otherwise.

This leads to a miscompile, because the stack slots actually are in-use
concurrently in the extracted function.

Fix this by moving lifetime start/end markers for memory regions defined
in the calling function around the call to the extracted function.

Fixes llvm.org/PR39671 (rdar://45939472).

Differential Revision: https://reviews.llvm.org/D55967

llvm-svn: 350420
2019-01-04 17:43:22 +00:00
Anna Thomas a470aa6701 [UnrollRuntime] Move the DomTree verification under expensive checks
Suggested by Hal as done in r349871.

llvm-svn: 350349
2019-01-03 19:43:33 +00:00
Anna Thomas 0785e7307e [UnrollRuntime] Add DomTree verification under debug mode
NFC: This adds the dom tree verification under debug mode at a point
just before we start unrolling the loop. This allows us to verify dom
tree at a state where it is much smaller and before the unrolling
actually happens.
This also implies we do not need to run -verify-dom-info everytime to
see if the DT is in a valid state when we transform the loop for runtime
unrolling.

llvm-svn: 350334
2019-01-03 17:44:44 +00:00
Philip Pfaffe b39a97c8f6 [NewPM] Port Msan
Summary:
Keeping msan a function pass requires replacing the module level initialization:
That means, don't define a ctor function which calls __msan_init, instead just
declare the init function at the first access, and add that to the global ctors
list.

Changes:
- Pull the actual sanitizer and the wrapper pass apart.
- Add a newpm msan pass. The function pass inserts calls to runtime
  library functions, for which it inserts declarations as necessary.
- Update tests.

Caveats:
- There is one test that I dropped, because it specifically tested the
  definition of the ctor.

Reviewers: chandlerc, fedor.sergeev, leonardchan, vitalybuka

Subscribers: sdardis, nemanjai, javed.absar, hiraditya, kbarton, bollu, atanasyan, jsji

Differential Revision: https://reviews.llvm.org/D55647

llvm-svn: 350305
2019-01-03 13:42:44 +00:00
Anna Thomas 98743fa77a [UnrollRuntime] NFC: Add comment and verify LCSSA
Added -verify-loop-lcssa to test cases.
Updated comments in ConnectProlog.

llvm-svn: 350131
2018-12-28 18:52:16 +00:00
Mircea Trofin b53eeb6f4c [llvm] API for encoding/decoding DWARF discriminators.
Summary:
Added a pair of APIs for encoding/decoding the 3 components of a DWARF discriminator described in http://lists.llvm.org/pipermail/llvm-dev/2016-October/106532.html: the base discriminator, the duplication factor (useful in profile-guided optimization) and the copy index (used to identify copies of code in cases like loop unrolling)

The encoding packs 3 unsigned values in 32 bits. This CL addresses 2 issues:
- communicates overflow back to the user
- supports encoding all 3 components together. Current APIs assume a sequencing of events. For example, creating a new discriminator based on an existing one by changing the base discriminator was not supported.

Reviewers: davidxl, danielcdh, wmi, dblaikie

Reviewed By: dblaikie

Subscribers: zzheng, dmgreen, aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D55681

llvm-svn: 349973
2018-12-21 22:48:50 +00:00
Vedant Kumar b264d69de7 [IR] Add Instruction::isLifetimeStartOrEnd, NFC
Instruction::isLifetimeStartOrEnd() checks whether an Instruction is an
llvm.lifetime.start or an llvm.lifetime.end intrinsic.

This was suggested as a cleanup in D55967.

Differential Revision: https://reviews.llvm.org/D56019

llvm-svn: 349964
2018-12-21 21:49:40 +00:00
Anna Thomas 18be3cb606 [RuntimeUnrolling] NFC: Add TODO and comments in connectProlog
Currently, runtime unrolling does not support loops where multiple
exiting blocks exit to the latchExit. Added TODO and other code
clarifications for ConnectProlog code.

llvm-svn: 349944
2018-12-21 19:45:05 +00:00
Eli Friedman 3af2f53456 [LoopUnroll] Don't verify domtree by default with +Asserts.
This verification is linear in the size of the function, so it can cause
a quadratic compile-time explosion in a function with many loops to
unroll.

Differential Revision: https://reviews.llvm.org/D54732

llvm-svn: 349871
2018-12-21 01:28:49 +00:00
Michael Kruse 978ba61536 Introduce llvm.loop.parallel_accesses and llvm.access.group metadata.
The current llvm.mem.parallel_loop_access metadata has a problem in that
it uses LoopIDs. LoopID unfortunately is not loop identifier. It is
neither unique (there's even a regression test assigning the some LoopID
to multiple loops; can otherwise happen if passes such as LoopVersioning
make copies of entire loops) nor persistent (every time a property is
removed/added from a LoopID's MDNode, it will also receive a new LoopID;
this happens e.g. when calling Loop::setLoopAlreadyUnrolled()).
Since most loop transformation passes change the loop attributes (even
if it just to mark that a loop should not be processed again as
llvm.loop.isvectorized does, for the versioned and unversioned loop),
the parallel access information is lost for any subsequent pass.

This patch unlinks LoopIDs and parallel accesses.
llvm.mem.parallel_loop_access metadata on instruction is replaced by
llvm.access.group metadata. llvm.access.group points to a distinct
MDNode with no operands (avoiding the problem to ever need to add/remove
operands), called "access group". Alternatively, it can point to a list
of access groups. The LoopID then has an attribute
llvm.loop.parallel_accesses with all the access groups that are parallel
(no dependencies carries by this loop).

This intentionally avoid any kind of "ID". Loops that are clones/have
their attributes modifies retain the llvm.loop.parallel_accesses
attribute. Access instructions that a cloned point to the same access
group. It is not necessary for each access to have it's own "ID" MDNode,
but those memory access instructions with the same behavior can be
grouped together.

The behavior of llvm.mem.parallel_loop_access is not changed by this
patch, but should be considered deprecated.

Differential Revision: https://reviews.llvm.org/D52116

llvm-svn: 349725
2018-12-20 04:58:07 +00:00
Vedant Kumar 9d1827331f [Util] Refer to [s|z]exts of args when converting dbg.declares (fix PR35400)
When converting dbg.declares, if the described value is a [s|z]ext,
refer to the ext directly instead of referring to its operand.

This fixes a narrowing bug (the debugger got the sign of a variable
wrong, see llvm.org/PR35400).

The main reason to refer to the ext's operand was that an optimization
may remove the ext itself, leading to a dropped variable. Now that
InstCombine has been taught to use replaceAllDbgUsesWith (r336451), this
is less of a concern. Other passes can/should adopt this API as needed
to fix dropped variable bugs.

Differential Revision: https://reviews.llvm.org/D51813

llvm-svn: 349214
2018-12-15 00:03:33 +00:00
Michael Kruse 5948b7f30f [Transforms] Preserve metadata when converting invoke to call.
The `changeToCall` function did not preserve the invoke's metadata.
Currently, there is probably no metadata that depends on being applied
on a CallInst or InvokeInst. Therefore we can replace the instruction's
metadata.

This fixes http://llvm.org/PR39994

Suggested-by: Moritz Kreutzer <moritz.kreutzer@siemens.com>

Differential Revision: https://reviews.llvm.org/D55666

llvm-svn: 349170
2018-12-14 18:15:11 +00:00
Easwaran Raman 5a7056fa03 [ThinLTO] Compute synthetic function entry count
Summary:
This patch computes the synthetic function entry count on the whole
program callgraph (based on module summary) and writes the entry counts
to the summary. After function importing, this count gets attached to
the IR as metadata. Since it adds a new field to the summary, this bumps
up the version.

Reviewers: tejohnson

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D43521

llvm-svn: 349076
2018-12-13 19:54:27 +00:00
Davide Italiano 9737096bb1 [LoopUtils] Use i32 instead of `void`.
The actual type of the first argument of the @dbg intrinsic
doesn't really matter as we're setting it to `undef`, but the
bitcode reader is picky about `void` types.

llvm-svn: 349069
2018-12-13 18:37:23 +00:00
Davide Italiano 8ee59ca653 [LoopUtils] Prefer a set over a map. NFCI.
llvm-svn: 348999
2018-12-13 01:11:52 +00:00
Davide Italiano 744c3c327f [LoopDeletion] Update debug values after loop deletion.
When loops are deleted, we don't keep track of variables modified inside
the loops, so the DI will contain the wrong value for these.

e.g.

int b() {

int i;
for (i = 0; i < 2; i++)
  ;
patatino();
return a;
-> 6 patatino();

7     return a;
8   }
9   int main() { b(); }
(lldb) frame var i
(int) i = 0

We mark instead these values as unavailable inserting a
@llvm.dbg.value(undef to make sure we don't end up printing an incorrect
value in the debugger. We could consider doing something fancier,
for, e.g. constants, in the future.

PR39868.
rdar://problem/46418795)

Differential Revision: https://reviews.llvm.org/D55299

llvm-svn: 348988
2018-12-12 23:32:35 +00:00
Michael Kruse 7244852557 [Unroll/UnrollAndJam/Vectorizer/Distribute] Add followup loop attributes.
When multiple loop transformation are defined in a loop's metadata, their order of execution is defined by the order of their respective passes in the pass pipeline. For instance, e.g.

    #pragma clang loop unroll_and_jam(enable)
    #pragma clang loop distribute(enable)

is the same as

    #pragma clang loop distribute(enable)
    #pragma clang loop unroll_and_jam(enable)

and will try to loop-distribute before Unroll-And-Jam because the LoopDistribute pass is scheduled after UnrollAndJam pass. UnrollAndJamPass only supports one inner loop, i.e. it will necessarily fail after loop distribution. It is not possible to specify another execution order. Also,t the order of passes in the pipeline is subject to change between versions of LLVM, optimization options and which pass manager is used.

This patch adds 'followup' attributes to various loop transformation passes. These attributes define which attributes the resulting loop of a transformation should have. For instance,

    !0 = !{!0, !1, !2}
    !1 = !{!"llvm.loop.unroll_and_jam.enable"}
    !2 = !{!"llvm.loop.unroll_and_jam.followup_inner", !3}
    !3 = !{!"llvm.loop.distribute.enable"}

defines a loop ID (!0) to be unrolled-and-jammed (!1) and then the attribute !3 to be added to the jammed inner loop, which contains the instruction to distribute the inner loop.

Currently, in both pass managers, pass execution is in a fixed order and UnrollAndJamPass will not execute again after LoopDistribute. We hope to fix this in the future by allowing pass managers to run passes until a fixpoint is reached, use Polly to perform these transformations, or add a loop transformation pass which takes the order issue into account.

For mandatory/forced transformations (e.g. by having been declared by #pragma omp simd), the user must be notified when a transformation could not be performed. It is not possible that the responsible pass emits such a warning because the transformation might be 'hidden' in a followup attribute when it is executed, or it is not present in the pipeline at all. For this reason, this patche introduces a WarnMissedTransformations pass, to warn about orphaned transformations.

Since this changes the user-visible diagnostic message when a transformation is applied, two test cases in the clang repository need to be updated.

To ensure that no other transformation is executed before the intended one, the attribute `llvm.loop.disable_nonforced` can be added which should disable transformation heuristics before the intended transformation is applied. E.g. it would be surprising if a loop is distributed before a #pragma unroll_and_jam is applied.

With more supported code transformations (loop fusion, interchange, stripmining, offloading, etc.), transformations can be used as building blocks for more complex transformations (e.g. stripmining+stripmining+interchange -> tiling).

Reviewed By: hfinkel, dmgreen

Differential Revision: https://reviews.llvm.org/D49281
Differential Revision: https://reviews.llvm.org/D55288

llvm-svn: 348944
2018-12-12 17:32:52 +00:00
Davide Italiano 8ec7709f58 [Local] Promote an utility that could be used elsewhere. NFCI.
llvm-svn: 348804
2018-12-10 22:17:04 +00:00
Vedant Kumar b2a6f8e505 [CodeExtractor] Store outputs at the first valid insertion point
When CodeExtractor outlines values which are used by the original
function, it must store those values in some in-out parameter. This
store instruction must not be inserted in between a PHI and an EH pad
instruction, as that results in invalid IR.

This fixes the following verifier failure seen while outlining within
ObjC methods with live exit values:

  The unwind destination does not have an exception handling instruction!
    %call35 = invoke i8* bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to i8* (i8*, i8*)*)(i8* %exn.adjusted, i8* %1)
            to label %invoke.cont34 unwind label %lpad33, !dbg !4183
  The unwind destination does not have an exception handling instruction!
    invoke void @objc_exception_throw(i8* %call35) #12
            to label %invoke.cont36 unwind label %lpad33, !dbg !4184
  LandingPadInst not the first non-PHI instruction in the block.
    %3 = landingpad { i8*, i32 }
            catch i8* null, !dbg !1411

rdar://46540815

llvm-svn: 348562
2018-12-07 03:01:54 +00:00
Vedant Kumar 09415a850e [CodeExtractor] Do not marked outlined calls which may resume EH as noreturn
Treat terminators which resume exception propagation as returning instructions
(at least, for the purposes of marking outlined functions `noreturn`). This is
to avoid inserting traps after calls to outlined functions which unwind.

rdar://46129950

llvm-svn: 348404
2018-12-05 19:35:37 +00:00
Vedant Kumar d129569e34 [CodeExtractor] Split PHI nodes with incoming values from outlined region (PR39433)
If a PHI node out of extracted region has multiple incoming values from it,
split this PHI on two parts. First PHI has incomings only from region and
extracts with it (they are placed to the separate basic block that added to the
list of outlined), and incoming values in original PHI are replaced by first
PHI. Similar solution is already used in CodeExtractor for PHIs in entry block
(severSplitPHINodes method). It covers PR39433 bug.

Patch by Sergei Kachkov!

Differential Revision: https://reviews.llvm.org/D55018

llvm-svn: 348205
2018-12-03 22:40:21 +00:00
Sanjay Patel 7d82d37854 [ValueTracking] add helper function for testing implied condition; NFCI
We were duplicating code around the existing isImpliedCondition() that
checks for a predecessor block/dominating condition, so make that a
wrapper call.

llvm-svn: 348088
2018-12-02 13:26:03 +00:00
Joseph Tremoulet 27b1e3bd4f [Mem2Reg] Fix nondeterministic corner case
Summary:
When mem2reg inserts phi nodes in blocks with unreachable predecessors,
it adds undef operands for those incoming edges.  When there are
multiple such predecessors, the order is currently based on the address
of the BasicBlocks.  This change fixes that by using the BBNumbers in
the sort/search predicates, as is done elsewhere in mem2reg to ensure
determinism.

Also adds a testcase with a bunch of unreachable preds, which
(nodeterministically) fails without the fix.


Reviewers: majnemer

Reviewed By: majnemer

Subscribers: mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D55077

llvm-svn: 348024
2018-11-30 19:20:02 +00:00
Jeremy Morse 9b4cfa55b1 [DebugInfo] Give inlinable calls DILocs (PR39807)
In PR39807 we incorrectly handle circumstances where calls are common'd
from conditional blocks into the parent BB. Calls that can be inlined
must always have DebugLocs, however we strip them during commoning, which
the IR verifier asserts on.

Fix this by using applyMergedLocation: it will perform the same DebugLoc
stripping of conditional Locs, but will also generate an unknown location
DebugLoc that satisfies the requirement for inlinable calls to always have
locations.

Some of the prior logic for selecting a DebugLoc is now likely redundant;
I'll generate a follow-up to remove it (involves editing more regression
tests).

Differential Revision: https://reviews.llvm.org/D54997

llvm-svn: 347782
2018-11-28 17:58:45 +00:00
Xin Tong 53e52e47e8 [ThinLTO] Correct linkonce_any function import linkage. NFC.
Summary:
This is a NFC as we do not import non-odr vague linkage when computing
for import list for a module.

Reviewers: tejohnson, pcc

Subscribers: inglorion, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D54928

llvm-svn: 347763
2018-11-28 15:16:35 +00:00
Xin Tong 04d49779a1 [ICP] Remove incompatible attributes at indirect-call promoted callsites.
Summary:
Removing ncompatible attributes at indirect-call promoted callsites, not removing it results in
at least a IR verification error.

Reviewers: davidxl, xur, mssimpso

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D54913

llvm-svn: 347605
2018-11-26 22:03:52 +00:00
Reid Kleckner 994a8451ba [Transforms] Prefer static and avoid namespaces, NFC
Put 'static' on three functions in an anonymous namespace as per our
coding style.

Remove the 'namespace llvm {}' around the .cpp file and explicitly
declare the free function 'llvm::optimizeGlobalCtorsList' in 'llvm::'.
I prefer this style for free functions because the compiler will error
out if the .h and .cpp files don't agree on the function name or
prototype.

llvm-svn: 347269
2018-11-19 22:19:05 +00:00
Vedant Kumar 4de31bba51 [IR] Add hasNPredecessors, hasNPredecessorsOrMore to BasicBlock
Add methods to BasicBlock which make it easier to efficiently check
whether a block has N (or more) predecessors.

This can be more efficient than using pred_size(), which is a linear
time operation.

We might consider adding similar methods for successors. I haven't done
so in this patch because succ_size() is already O(1).

With this patch applied, I measured a 0.065% compile-time reduction in
user time for running `opt -O3` on the sqlite3 amalgamation (30 trials).
The change in mergeStoreIntoSuccessor alone saves 45 million linked list
iterations in a stage2 Release build of llc.

See llvm.org/PR39702 for a harder but more general way of achieving
similar results.

Differential Revision: https://reviews.llvm.org/D54686

llvm-svn: 347256
2018-11-19 19:54:27 +00:00
Eugene Leviant bf46e7410c [ThinLTO] Internalize readonly globals
An attempt to recommit r346584 after failure on OSX build bot.
Fixed cache key computation in ThinLTOCodeGenerator and added
test case

llvm-svn: 347033
2018-11-16 07:08:00 +00:00
Reid Kleckner 41390b47de Revert r346810 "Preserve loop metadata when splitting exit blocks"
It broke the Windows self-host:
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/1457

llvm-svn: 346823
2018-11-14 01:47:32 +00:00
Craig Topper 3c87c2a3c5 Preserve loop metadata when splitting exit blocks
LoopUtils.cpp contains a utility that splits an loop exit block, so that the new block contains only edges coming from the loop. In the case of nested loops, the exit path for the inner loop might also be the back-edge of the outer loop. The new block which is inserted on this path, is now a latch for the outer loop, and it needs to hold the loop metadata for the outer loop. (The test case gives a more concrete view of the situation.)

Patch by Chang Lin (clin1)

Differential Revision: https://reviews.llvm.org/D53876

llvm-svn: 346810
2018-11-13 23:06:49 +00:00
Florian Hahn 107d0a8756 [CSP, Cloning] Update DuplicateInstructionsInSplitBetween to use DomTreeUpdater.
This patch updates DuplicateInstructionsInSplitBetween to update a DTU
instead of applying updates to the DT directly.

Given that there only are 2 users, also updated them in this patch to
avoid churn.

I slightly moved the code in CallSiteSplitting around to reduce the
places where we have to pass in DTU. If necessary, I could split those
changes in a separate patch.

This fixes missing DT updates when dealing with musttail calls in
CallSiteSplitting, by using DTU->deleteBB.

Reviewers: junbuml, kuhar, NutshellySima, indutny, brzycki

Reviewed By: NutshellySima

llvm-svn: 346769
2018-11-13 17:54:43 +00:00
Steven Wu fa43892d6f Revert "[ThinLTO] Internalize readonly globals"
This reverts commit 10c84a8f35cae4a9fc421648d9608fccda3925f2.

llvm-svn: 346768
2018-11-13 17:35:04 +00:00
Eugene Leviant be8d19967a [ThinLTO] Internalize readonly globals
This patch allows internalising globals if all accesses to them
(from live functions) are from non-volatile load instructions

Differential revision: https://reviews.llvm.org/D49362

llvm-svn: 346584
2018-11-10 08:31:21 +00:00
Carlos Alberto Enciso fa9cf89734 [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.
In SimplifyCFG when given a conditional branch that goes to BB1 and BB2, the hoisted common terminator instruction in the two blocks, caused debug line records associated with subsequent select instructions to become ambiguous. It causes the debugger to display unreachable source lines.

Differential Revision: https://reviews.llvm.org/D53390

llvm-svn: 346481
2018-11-09 09:42:10 +00:00
Vedant Kumar d6699423f1 [CodeExtractor] Mark functions noreturn when applicable
This eliminates the outlining penalty for llvm.trap/unreachable, because
callers no longer have to emit cleanup/ret instructions after calling an
outlined `noreturn` function.

rdar://45523626

llvm-svn: 346421
2018-11-08 17:57:09 +00:00
Vedant Kumar 1e209e284f [CodeExtractor] Do not extract calls to eh_typeid_for (PR39545)
The lowering for a call to eh_typeid_for changes when it's moved from
one function to another.

There are several proposals for fixing this issue in llvm.org/PR39545.
Until some solution is in place, do not allow CodeExtractor to extract
calls to eh_typeid_for, as that results in serious miscompilations.

llvm-svn: 346256
2018-11-06 19:06:08 +00:00
Vedant Kumar 09b7aa443d [CodeExtractor] Erase use-without-def debug intrinsics in parent func
When CodeExtractor moves instructions to a new function, debug
intrinsics referring to those instructions within the parent function
become invalid.

This results in the same verifier failure which motivated r344545, about
function-local metadata being used in the wrong function.

llvm-svn: 346255
2018-11-06 19:05:53 +00:00
Reid Kleckner 3f756fbabe Remove unnecessary fallthrough annotation after unreachable
Clang's -Wimplicit-fallthrough implementation warns on this. I built
clang with GCC 7.3 in +asserts and -asserts mode, and GCC doesn't warn
on this in either configuration. I think it is unnecessary. I separated
it from the large mechanical patch (https://reviews.llvm.org/D53950) in
case I am wrong and it has to be reverted.

llvm-svn: 345876
2018-11-01 19:11:05 +00:00
Matthias Braun 9fd397b423 ADT/STLExtras: Introduce llvm::empty; NFC
This is modeled after C++17 std::empty().

Differential Revision: https://reviews.llvm.org/D53909

llvm-svn: 345679
2018-10-31 00:23:23 +00:00
Florian Hahn fc7654a67b [Local] Keep K's range if K does not move when combining metadata.
As K has to dominate I, IIUC I's range metadata must be a subset of
K's. After Eli's recent clarification to the LangRef, loading a value
outside of the range is undefined behavior.
Therefore if I's range contains elements outside of K's range and we would load
one such value, K would cause undefined behavior.

In cases like hoisting/sinking, we still want the most generic range
over all code paths to/from the hoist/sink point. As suggested in the
patches related to D47339, I will refactor the handling of those
scenarios and try to decouple it from this function as follow up, once
we switched to a similar handling of metadata in most of
combineMetadata.

I updated some tests checking mostly the merging of metadata to keep the
metadata of to dominating load. The most interesting one is probably test8 in
test/Transforms/JumpThreading/thread-loads.ll. It contained a comment
about the alias metadata preventing us to eliminate the branch, but it
seem like the actual problem currently is that we merge the ranges of
both loads and cannot eliminate the icmp afterwards. With this patch, we
manage to eliminate the icmp, as the range of the first load excludes 8.

Reviewers: efriedma, nlopes, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D51629

llvm-svn: 345456
2018-10-27 16:53:45 +00:00
Carlos Alberto Enciso 9a24e1a7cd [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.
When SimplifyCFG changes the PHI node into a select instruction, the debug line records becomes ambiguous. It causes the debugger to display unreachable source lines.

Differential Revision: https://reviews.llvm.org/D53287

llvm-svn: 345250
2018-10-25 09:58:59 +00:00
Alina Sbirlea ad4d018202 Update MemorySSA in LoopRotate.
Summary:
Teach LoopRotate to preserve MemorySSA.
Enable tests for correctness, dependency disabled by default.

Subscribers: sanjoy, jlebar, Prazek, george.burgess.iv, llvm-commits

Differential Revision: https://reviews.llvm.org/D51718

llvm-svn: 345216
2018-10-24 22:46:45 +00:00
Vedant Kumar c299006879 [HotColdSplitting] Identify larger cold regions using domtree queries
The current splitting algorithm works in three stages:

  1) Identify cold blocks, then
  2) Use forward/backward propagation to mark hot blocks, then
  3) Grow a SESE region of blocks *outside* of the set of hot blocks and
  start outlining.

While testing this pass on Apple internal frameworks I noticed that some
kinds of control flow (e.g. loops) are never outlined, even though they
unconditionally lead to / follow cold blocks. I noticed two other issues
related to how cold regions are identified:

  - An inconsistency can arise in the internal state of the hotness
  propagation stage, as a block may end up in both the ColdBlocks set
  and the HotBlocks set. Further inconsistencies can arise as these sets
  do not match what's in ProfileSummaryInfo.

  - It isn't necessary to limit outlining to single-exit regions.

This patch teaches the splitting algorithm to identify maximal cold
regions and outline them. A maximal cold region is defined as the set of
blocks post-dominated by a cold sink block, or dominated by that sink
block. This approach can successfully outline loops in the cold path. As
a side benefit, it maintains less internal state than the current
approach.

Due to a limitation in CodeExtractor, blocks within the maximal cold
region which aren't dominated by a single entry point (a so-called "max
ancestor") are filtered out.

Results:
  - X86 (LNT + -Os + externals): 134KB of TEXT were outlined compared to
  47KB pre-patch, or a ~3x improvement. Did not see a performance impact
  across two runs.
  - AArch64 (LNT + -Os + externals + Apple-internal benchmarks): 149KB
  of TEXT were outlined. Ditto re: performance impact.
  - Outlining results improve marginally in the internal frameworks I
  tested.

Follow-ups:
  - Outline more than once per function, outline large single basic
  blocks, & try to remove unconditional branches in outlined functions.

Differential Revision: https://reviews.llvm.org/D53627

llvm-svn: 345209
2018-10-24 22:15:41 +00:00
Teresa Johnson c8dba682bb [hot-cold-split] Name split functions with ".cold" suffix
Summary:
The current default of appending "_"+entry block label to the new
extracted cold function breaks demangling. Change the deliminator from
"_" to "." to enable demangling. Because the header block label will
be empty for release compile code, use "extracted" after the "." when
the label is empty.

Additionally, add a mechanism for the client to pass in an alternate
suffix applied after the ".", and have the hot cold split pass use
"cold."+Count, where the Count is currently 1 but can be used to
uniquely number multiple cold functions split out from the same function
with D53588.

Reviewers: sebpop, hiraditya

Subscribers: llvm-commits, erik.pilkington

Differential Revision: https://reviews.llvm.org/D53534

llvm-svn: 345178
2018-10-24 18:53:47 +00:00
Evandro Menezes 164ea101ab [NFC][InstCombine] Undo stray change
Undo stray change introduced by r344725.

llvm-svn: 344814
2018-10-19 20:57:45 +00:00
Mikael Holmen e3605d0f70 Add a emitUnaryFloatFnCall version that fetches the function name from TLI
Summary:
In several places in the code we use the following pattern:

  if (hasUnaryFloatFn(&TLI, Ty, LibFunc_tan, LibFunc_tanf, LibFunc_tanl)) {
    [...]
    Value *Res = emitUnaryFloatFnCall(X, TLI.getName(LibFunc_tan), B, Attrs);
    [...]
  }

In short, we check if there is a lib-function for a certain type, and then
we _always_ fetch the name of the "double" version of the lib function and
construct a call to the appropriate function, that we just checked exists,
using that "double" name as a basis.

This is of course a problem in cases where the target doesn't support the
"double" version, but e.g. only the "float" version.

In that case TLI.getName(LibFunc_tan) returns "", and
emitUnaryFloatFnCall happily appends an "f" to "", and we erroneously end
up with a call to a function called "f".

To solve this, the above pattern is changed to

  if (hasUnaryFloatFn(&TLI, Ty, LibFunc_tan, LibFunc_tanf, LibFunc_tanl)) {
    [...]
    Value *Res = emitUnaryFloatFnCall(X, &TLI, LibFunc_tan, LibFunc_tanf,
                                      LibFunc_tanl, B, Attrs);
    [...]
  }

I.e instead of first fetching the name of the "double" version and then
letting emitUnaryFloatFnCall() add the final "f" or "l", we let
emitUnaryFloatFnCall() fetch the right name from TLI.

Reviewers: eli.friedman, efriedma

Reviewed By: efriedma

Subscribers: efriedma, bjope, llvm-commits

Differential Revision: https://reviews.llvm.org/D53370

llvm-svn: 344725
2018-10-18 06:27:53 +00:00
Chandler Carruth c8eaea71c9 [TI removal] Use `Instruction` instead of `TerminatorInst` for
a variable's type.

llvm-svn: 344717
2018-10-18 00:39:18 +00:00
Chandler Carruth 8b7a8123dd [TI removal] Update CodeExtractor to use Instruction directly.
llvm-svn: 344716
2018-10-18 00:38:54 +00:00
David Bolvansky 7c7760da7e [InstCombine] Cleanup libfunc attribute inferring
Reviewers: efriedma

Reviewed By: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D53338

llvm-svn: 344645
2018-10-16 21:18:31 +00:00
Max Kazantsev 9c90ec2fae [NFC] Make LoopSafetyInfo abstract to allow alternative implementations
llvm-svn: 344592
2018-10-16 08:31:05 +00:00
David Stenberg c9163855dd [DebugInfo][LCSSA] Rewrite pre-existing debug values outside loop
Summary:
Extend LCSSA so that debug values outside loops are rewritten to
use the PHI nodes that the pass creates.

This fixes PR39019. In that case, we ran LCSSA on a loop that
was later on vectorized, which left us with something like this:

  for.cond.cleanup:
    %add.lcssa = phi i32 [ %add, %for.body ], [ %34, %middle.block ]
    call void @llvm.dbg.value(metadata i32 %add,
    ret i32 %add.lcssa

  for.body:
    %add =
    [...]
    br i1 %exitcond, label %for.cond.cleanup, label %for.body

which later resulted in the debug.value becoming undef when
removing the scalar loop (and the location would have probably
been wrong for the vectorized case otherwise).

As we now may need to query the AvailableVals cache more than
once for a basic block, FindAvailableVals() in SSAUpdaterImpl is
changed so that it updates the cache for blocks that we do not
create a PHI node for, regardless of the block's number of
predecessors. The debug value in the attached IR reproducer
would not be properly rewritten without this.

Debug values residing in blocks where we have not inserted any
PHI nodes are currently left as-is by this patch. I'm not sure
what should be done with those uses.

Reviewers: mattd, aprantl, vsk, probinson

Reviewed By: mattd, aprantl

Subscribers: jmorse, gbedwell, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D53130

llvm-svn: 344589
2018-10-16 08:06:48 +00:00
Vedant Kumar 15718a6190 [CodeExtractor] Erase debug intrinsics in outlined thunks (fix PR22900)
Variable updates within the outlined function are invisible to
debuggers. This could be improved by defining a DISubprogram for the
new function. For the moment, simply erase the debug intrinsics instead.

This fixes verifier failures about function-local metadata being used in
the wrong function, seen while testing the hot/cold splitting pass.

rdar://45142482

Differential Revision: https://reviews.llvm.org/D53267

llvm-svn: 344545
2018-10-15 19:22:20 +00:00
Chandler Carruth edb12a838a [TI removal] Make variables declared as `TerminatorInst` and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

llvm-svn: 344502
2018-10-15 10:04:59 +00:00
Chandler Carruth 4a2d58e16a [TI removal] Remove `TerminatorInst` from BasicBlockUtils.h
This requires updating a number of .cpp files to adapt to the new API.
I've just systematically updated all uses of `TerminatorInst` within
these files te `Instruction` so thta I won't have to touch them again in
the future.

llvm-svn: 344498
2018-10-15 09:34:05 +00:00
Chandler Carruth b99a24689b [TI removal] Remove TerminatorInst as an input parameter from all public
LLVM APIs. There weren't very many.

We still have the instruction visitor, and APIs with TerminatorInst as
a return type or an output parameter.

llvm-svn: 344494
2018-10-15 09:17:09 +00:00
David Bolvansky e8b3bba717 [InstCombine] Fixed crash with aliased functions
Summary: Fixes PR39177

Reviewers: spatel, jbuening

Reviewed By: jbuening

Subscribers: jbuening, llvm-commits

Differential Revision: https://reviews.llvm.org/D53129

llvm-svn: 344454
2018-10-13 15:21:55 +00:00
Amara Emerson 54f60255a2 [InstCombine] Fix SimplifyLibCalls erasing an instruction while IC still had references to it.
InstCombine keeps a worklist and assumes that optimizations don't
eraseFromParent() the instruction, which SimplifyLibCalls violates. This change
adds a new callback to SimplifyLibCalls to let clients specify their own hander
for erasing actions.

Differential Revision: https://reviews.llvm.org/D52729

llvm-svn: 344251
2018-10-11 14:51:11 +00:00
Max Kazantsev b2e51090a4 [IndVars] Drop "exact" flag from lshr and udiv when substituting their args
There is a transform that may replace `lshr (x+1), 1` with `lshr x, 1` in case
if it can prove that the result will be the same. However the initial instruction
might have an `exact` flag set, and it now should be dropped unless we prove
that it may hold. Incorrectly set `exact` attribute may then produce poison.

Differential Revision: https://reviews.llvm.org/D53061
Reviewed By: sanjoy

llvm-svn: 344223
2018-10-11 07:22:26 +00:00
Scott Linder 3759efc650 Relax trivial cast requirements in CallPromotionUtils
Differential Revision: https://reviews.llvm.org/D52792

llvm-svn: 344153
2018-10-10 16:35:47 +00:00
Carlos Alberto Enciso c0952c8a08 Revert "[DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG."
This reverts commit r344120.

It was causing buildbot failures.

llvm-svn: 344135
2018-10-10 12:09:34 +00:00
Carlos Alberto Enciso e7a347e5f8 [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.
When SimplifyCFG changes the PHI node into a select instruction, the debug line records becomes ambiguous. It causes the debugger to display unreachable source lines. 

Differential Revision: https://reviews.llvm.org/D52887

llvm-svn: 344120
2018-10-10 08:29:55 +00:00
Max Kazantsev 1d893bfcea [NFC] Make a variable const
llvm-svn: 344113
2018-10-10 04:19:38 +00:00
Craig Topper 029d1ef6eb [SimplifyCFG] Pass AggressiveInsts to DominatesMergePoint by reference. Remove null check.
Summary:
At some point in the past the recursion in DominatesMergePoint used to pass null for AggressiveInsts as part of the recursion. It no longer does this. So there is no way for AggressiveInsts to be null.

This passes it by reference and removes the null check to make this explicit.

Reviewers: efriedma, reames

Reviewed By: efriedma

Subscribers: xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D52575

llvm-svn: 343828
2018-10-04 23:40:31 +00:00
Craig Topper 1d15f7b02b [SimplifyCFG] Change recursive calls to llvm::SimplifyCFG to instead use an outer while loop to revisit.
Summary:
The llvm::SimplifyCFG function creates a SimplifyCFGOpt object and calls run on it. There were numerous places reached from this run function that called back out llvm::SimplifyCFG which would create another SimplifyCFGOpt object. This is an inefficient use of stack space at minimum. We are also not passing along the LoopHeaders pointer passed into the outer llvm::SimplifyCFG call. So if its not null we lose it on the first recursion and get nullptr from there on.

This patch adds an outer loop around the main BasicBlock simplifying code and adds a flag to the SimplifyCFGOpt class that can be set by to request another iteration. I don't think we can iterate based just on the change flag alone since some of the simplifications delete a basic block entirely leaving nothing to iterate on.

Reviewers: bogner, eli.friedman, reames

Reviewed By: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52760

llvm-svn: 343816
2018-10-04 21:11:52 +00:00
Craig Topper d616d33a96 [SimplifyCFG] Use Value::hasNUses instead of 'getNumUses() =='. NFCI
getNumUses is linear in the number of uses. Since we're looking for a specific use count, we can use hasNUses which will stop as soon as it determines there are more than N uses instead of walking all of them.

llvm-svn: 343550
2018-10-01 23:09:52 +00:00
Craig Topper 90c0a0621c [SimplifyCFG] Update comments that refer to CondBB to say ThenBB instead. NFC
There is no variable in this function named CondBB, but there is one named ThenBB and I believe the comments are all refering to it.

llvm-svn: 343548
2018-10-01 22:56:11 +00:00
Fangrui Song 3507c6e884 Use the container form llvm::sort(C, ...)
There are a few leftovers in rL343163 which span two lines. This commit
changes these llvm::sort(C.begin(), C.end, ...) to llvm::sort(C, ...)

llvm-svn: 343426
2018-09-30 22:31:29 +00:00
Fangrui Song 0cac726a00 llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...)
Summary: The convenience wrapper in STLExtras is available since rL342102.

Reviewers: dblaikie, javed.absar, JDevlieghere, andreadb

Subscribers: MatzeB, sanjoy, arsenm, dschuff, mehdi_amini, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, javed.absar, gbedwell, jrtc27, mgrang, atanasyan, steven_wu, george.burgess.iv, dexonsmith, kristina, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D52573

llvm-svn: 343163
2018-09-27 02:13:45 +00:00
Vyacheslav Zakharin e06831a3b2 Remove LoopID metadata from the branch instruction
that follows the peeled iterations.

Differential Revision: https://reviews.llvm.org/D52176

llvm-svn: 343054
2018-09-26 01:03:21 +00:00
David Green 9108c2b921 [LoopUnroll] Add check to Latch's terminator in UnrollRuntimeLoopRemainder
In this patch, I'm adding an extra check to the Latch's terminator in llvm::UnrollRuntimeLoopRemainder,
similar to how it is already done in the llvm::UnrollLoop.

The compiler would crash if this function is called with a malformed loop.

Patch by Rodrigo Caetano Rocha!

Differential Revision: https://reviews.llvm.org/D51486

llvm-svn: 342958
2018-09-25 10:08:47 +00:00
Matt Morehouse e62fc3d0b6 [InstCombine] Disable strcmp->memcmp transform for MSan.
Summary:
The strcmp->memcmp transform can make the resulting memcmp read
uninitialized data, which MSan doesn't like.

Resolves https://github.com/google/sanitizers/issues/993.

Reviewers: eugenis, xbolva00

Reviewed By: eugenis

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D52272

llvm-svn: 342582
2018-09-19 19:37:24 +00:00
Benjamin Kramer e5e1ea79fd [InstCombine] Don't transform sin/cos -> tanl if for half types
This is still unsafe for long double, we will transform things into tanl
even if tanl is for another type. But that's for someone else to fix.

llvm-svn: 342542
2018-09-19 12:01:38 +00:00
Carlos Alberto Enciso ba4e437c6a [DebugInfo][Dexter] Speculated BB presents illegal variable value to debugger.
When SimplifyCFG changes the PHI node into a select instruction, the debug information becomes ambiguous. It causes the debugger to display wrong variable value. 

Differential Revision: https://reviews.llvm.org/D51976

llvm-svn: 342527
2018-09-19 08:16:56 +00:00
David Green 2352b30c96 [SimplifyCFG] Put an alignment on generated switch tables
Previously the alignment on the newly created switch table data was not set,
meaning that DataLayout::getPreferredAlignment was free to overalign it to 16
bytes. This causes unnecessary code bloat.

Differential Revision: https://reviews.llvm.org/D51800

llvm-svn: 342039
2018-09-12 09:54:17 +00:00
Vikram TV 7e98d69847 Break LoopUtils into an Analysis file.
Summary:
The InductionDescriptor and RecurrenceDescriptor classes basically analyze the IR to identify the respective IVs. So, it is better to have them in the "Analysis" directory instead of the "Transforms" directory.

The rationale for this is to make the Induction and Recurrence descriptor classes available for analysis passes. Currently including them in an analysis pass produces link error (http://lists.llvm.org/pipermail/llvm-dev/2018-July/124456.html).

Induction and Recurrence descriptors are moved from Transforms/Utils/LoopUtils.h|cpp to Analysis/IVDescriptors.h|cpp.

Reviewers: dmgreen, llvm-commits, hfinkel

Reviewed By: dmgreen

Subscribers: mgorny

Differential Revision: https://reviews.llvm.org/D51153

llvm-svn: 342016
2018-09-12 01:59:43 +00:00
Benjamin Kramer 28559a2605 Don't create a temporary vector of loop blocks just to iterate over them.
Loop's getBlocks returns an ArrayRef.

llvm-svn: 341821
2018-09-10 12:32:06 +00:00
Vikram TV 09be521d4d Move a transformation routine from LoopUtils to LoopVectorize.
Summary:
Move InductionDescriptor::transform() routine from LoopUtils to its only uses in LoopVectorize.cpp.
Specifically, the function is renamed as InnerLoopVectorizer::emitTransformedIndex().

This is a child to D51153.

Reviewers: dmgreen, llvm-commits

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D51837

llvm-svn: 341776
2018-09-10 06:16:44 +00:00
Vikram TV 6594dc377d Move createMinMaxOp() out of RecurrenceDescriptor.
Reviewers: dmgreen, llvm-commits

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D51838

llvm-svn: 341773
2018-09-10 05:05:08 +00:00
Alina Sbirlea f98c2c5e6d [MemorySSA] Update MemoryPhi wiring for block splitting to consider if identical edges were merged.
Summary:
Block splitting is done with either identical edges being merged, or not.
Only critical edges can be split without merging identical edges based on an option.
Teach the memoryssa updater to take this into account: for the same edge between two blocks only move one entry from the Phi in Old to the new Phi in New.

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D51563

llvm-svn: 341709
2018-09-07 21:14:48 +00:00