Commit Graph

19317 Commits

Author SHA1 Message Date
Marcello Maggioni ddccd50313 [NFC] Commit to mention that r322248 is actually made by AndrewScheidecker
llvm-svn: 322249
2018-01-11 02:06:28 +00:00
Marcello Maggioni 7083423f22 [SimplifyCFG] Add cut-off for InitializeUniqueCases.
The function can take a significant amount of time on some
complicated test cases, but for the currently only use of
the function we can stop the initialization much earlier
when we find out we are going to discard the result anyway
in the caller of the function.

Adding configurable cut-off points so that we avoid wasting time.
NFCI.

llvm-svn: 322248
2018-01-11 02:01:16 +00:00
Justin Lebar 9d3afd3c06 Add explanatory comment to LoadStoreVectorizer.
Reviewers: arsenm

Subscribers: rengolin, sanjoy, wdng, hiraditya, asbirlea

Differential Revision: https://reviews.llvm.org/D41890

llvm-svn: 322157
2018-01-10 03:02:12 +00:00
Vlad Tsyrklevich cdec22ef9a LowerTypeTests: Add limited support for aliases
Summary:
LowerTypeTests moves some function definitions from individual object
files to the merged module, leaving a stub to be called in the merged
module's jump table. If an alias was pointing to such a function
definition LowerTypeTests would fail because the alias would be left
without a definition to point to.

This change 1) emits information about aliases to the ThinLTO summary,
2) replaces aliases pointing to function definitions that are moved to
the merged module with function declarations, and 3) re-emits those
aliases in the merged module pointing to the correct function
definitions.

The patch does not correctly fix all possible mis-uses of aliases in
LowerTypeTests. For example, it does not handle aliases with a different
type from the pointed to function.

The addition of alias data increases the size of Chrome build artifacts
by less than 1%.

Reviewers: pcc

Reviewed By: pcc

Subscribers: mehdi_amini, eraman, mgrang, llvm-commits, eugenis, kcc

Differential Revision: https://reviews.llvm.org/D41741

llvm-svn: 322139
2018-01-10 00:00:51 +00:00
Michael Zolotukhin 1f562176e9 [LoopRotate] Detect loops with indirect branches better (we're giving up on them).
llvm-svn: 322137
2018-01-09 23:54:35 +00:00
Chris Bieneman abdea268c1 [IPSCCP] Remove calls without side effects
Summary:
When performing constant propagation for call instructions we have historically replaced all uses of the return from a call, but not removed the call itself. This is required for correctness if the calls have side effects, however the compiler should be able to safely remove calls that don't have side effects.

This allows the compiler to completely fold away calls to functions that have no side effects if the inputs are constant and the output can be determined at compile time.

Reviewers: davide, sanjoy, bruno, dberlin

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38856

llvm-svn: 322125
2018-01-09 21:58:46 +00:00
Daniel Berlin 56cca7437c NewGVN: Fix PR/33367, which was causing us to delete non-copy intrinsics accidentally in some rare cases
llvm-svn: 322115
2018-01-09 20:12:42 +00:00
Easwaran Raman bdf20261d8 Add a pass to generate synthetic function entry counts.
Summary:
This pass synthesizes function entry counts by traversing the callgraph
and using the relative block frequencies of the callsites. The intended
use of these counts is in inlining to determine hot/cold callsites in
the absence of profile information.

The pass is split into two files with the code that propagates the
counts in a callgraph in a Utils file. I plan to add support for
propagation in the thinlto link phase and the propagation code will be
shared and hence this split. I did not add support to the old PM since
hot callsite determination in inlining is not possible in old PM
(although we could use hot callee heuristic with synthetic counts in the
old PM it is not worth the effort tuning it)

Reviewers: davidxl, silvas

Subscribers: mgorny, mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D41604

llvm-svn: 322110
2018-01-09 19:39:35 +00:00
Sanjay Patel 6fb1357c35 [InstCombine] weaken assertions for icmp folds (PR35846)
Because of potential UB (known bits conflicts with an llvm.assume),
we have to check rather than assert here because InstSimplify doesn't
kill the compare:
https://bugs.llvm.org/show_bug.cgi?id=35846

llvm-svn: 322104
2018-01-09 18:56:03 +00:00
Petar Jovanovic 1d26c7e4ff [EarlyCSE] Salvage debug info during DCE
EarlyCSE did not try to salvage debug info during erasing of instructions.
This change fixes it.

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D41496

llvm-svn: 322083
2018-01-09 15:08:37 +00:00
Simon Pilgrim 5d909be91b [InstCombine] Check for out of range ashr values using APInt before calling getZExtValue
Reduced from oss-fuzz #5032 test case

llvm-svn: 322078
2018-01-09 14:23:46 +00:00
Justin Bogner 6f6846fc9d AlwaysInliner: Alow setting InsertLifetime in the new-style pass
llvm-svn: 322033
2018-01-08 22:07:42 +00:00
Justin Bogner 92fe563b57 ArgPromotion: Allow setting MaxElements in the new-style pass
llvm-svn: 322025
2018-01-08 21:13:35 +00:00
Davide Italiano 9a60d2c157 [CVP] Replace incoming values from unreachable blocks with undef.
This is an attempt of fixing PR35807.
Due to the non-standard definition of dominance in LLVM, where uses in
unreachable blocks are dominated by anything, you can have, in an
unreachable block:

  %patatino = OP1 %patatino, CONSTANT

When `SimplifyInstruction` receives a PHI where an incoming value is of
the aforementioned form, in some cases, loops indefinitely.

What I propose here instead is keeping track of the incoming values
from unreachable blocks, and replacing them with undef. It fixes this
case, and it seems to be good regardless (even if we can't prove that
the value is constant, as it's coming from an unreachable block, we
can ignore it).

Differential Revision:  https://reviews.llvm.org/D41812

llvm-svn: 322006
2018-01-08 16:34:06 +00:00
Sanjay Patel 31b4b76f99 [InstCombine] fold min/max tree with common operand (PR35717)
There is precedence for factorization transforms in instcombine for FP ops with fast-math. 
We also have similar logic in foldSPFofSPF().

It would take more work to add this to reassociate because that's specialized for binops, 
and min/max are not binops (or even single instructions). Also, I don't have evidence that 
larger min/max trees than this exist in real code, but if we find that's true, we might
want to reorganize where/how we do this optimization.

In the motivating example from https://bugs.llvm.org/show_bug.cgi?id=35717 , we have:

int test(int xc, int xm, int xy) {
  int xk;
  if (xc < xm)
    xk = xc < xy ? xc : xy;
  else
    xk = xm < xy ? xm : xy;
  return xk;
}

This patch solves that problem because we recognize more min/max patterns after rL321672

https://rise4fun.com/Alive/Qjne
https://rise4fun.com/Alive/3yg

Differential Revision: https://reviews.llvm.org/D41603

llvm-svn: 321998
2018-01-08 15:05:34 +00:00
Alexey Bataev 5b9a77d4ea [SLP] Fix PR35777: Incorrect handling of aggregate values.
Summary:
Fixes the bug with incorrect handling of InsertValue|InsertElement
instrucions in SLP vectorizer. Currently, we may use incorrect
ExtractElement instructions as the operands of the original
InsertValue|InsertElement instructions.

Reviewers: mkuper, hfinkel, RKSimon, spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41767

llvm-svn: 321994
2018-01-08 14:43:06 +00:00
Alexey Bataev 118a0a2c38 [SLP] Fix PR35628: Count external uses on extra reduction arguments.
Summary:
If the vectorized value is marked as extra reduction argument, its users
are not considered as external users. Patch fixes this.

Reviewers: mkuper, hfinkel, RKSimon, spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41786

llvm-svn: 321993
2018-01-08 14:33:11 +00:00
Davide Italiano e15bffe9ea Revert "[SCCP] Manually fold branches on undef."
I thought this was responsible for PR35723, but I was
wrong, the issue lies elsewhere. Revert while I debug.

llvm-svn: 321975
2018-01-07 22:09:44 +00:00
Davide Italiano 4c39758a38 [SLPVectorizer] Reintroduce std::stable_sort(properlyDominates()).
The approach was never discussed, I wasn't able to reproduce this
non-determinism, and the original author went AWOL.
After a discussion on the ML, Philip suggested to revert this.

llvm-svn: 321974
2018-01-07 22:06:24 +00:00
Hal Finkel 0f1314c5ee [LV][VPlan] NFC patch to move LoopVectorizationPlanner class out of LoopVectorize.cpp
Another small step forward to move VPlan stuff outside of LoopVectorize.cpp.

VPlanBuilder.h is renamed to LoopVectorizationPlanner.h
LoopVectorizationPlanner class is moved from LoopVectorize.cpp to
LoopVectorizationPlanner.h LoopVectorizationCostModel::VectorizationFactor
class is moved to LoopVectorizationPlanner.h (used by the planner class) ---
this needs further streamlining work in later patches and thus all I did was
take it out of the CostModel class and moved to the header file.  The callback
function had to stay inside LoopVectorize.cpp since it calls an
InnerLoopVectorizer member function declared in it.  Next Steps: Make
InnerLoopVectorizer, LoopVectorizationCostModel, and other classes more modular
and more aligned with VPlan direction, in small increments.

Previous step was: r320900 (https://reviews.llvm.org/D41045)

Patch by Hideki Saito, thanks!

Differential Revision: https://reviews.llvm.org/D41420

llvm-svn: 321962
2018-01-07 16:02:58 +00:00
Florian Hahn 55be37e7d4 [CodeExtractor] Use subset of function attributes for extracted function.
In addition to target-dependent attributes, we can also preserve a
white-listed subset of target independent function attributes. The white-list
excludes problematic attributes, most prominently:

* attributes related to memory accesses, as alloca instructions
  could be moved in/out of the extracted block

* control-flow dependent attributes, like no_return or thunk, as the
  relerelevant instructions might or might not get extracted.

Thanks @efriedma and @aemerson for providing a set of attributes that cannot be
propagated.


Reviewers: efriedma, davidxl, davide, silvas

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D41334

llvm-svn: 321961
2018-01-07 11:22:25 +00:00
Florian Hahn a82eef2363 [InlineFunction] Preserve calling convention when forwarding VarArgs.
Reviewers: efriedma, rnk, davide

Reviewed By: rnk, davide

Differential Revision: https://reviews.llvm.org/D41556

llvm-svn: 321943
2018-01-06 20:56:27 +00:00
Florian Hahn de10e6e064 [InlineFunction] Preserve attributes when forwarding VarArgs.
Reviewers: rnk, efriedma

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D41555

llvm-svn: 321942
2018-01-06 20:46:00 +00:00
Florian Hahn 80788d8088 [InlineFunction] Inline vararg functions that do not access varargs.
If the varargs are not accessed by a function, we can inline the
function.

Reviewers: dblaikie, chandlerc, davide, efriedma, rnk, hfinkel

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D41335

llvm-svn: 321940
2018-01-06 19:45:40 +00:00
Sanjay Patel 26a6fcde83 [InstCombine] relax use constraint for min/max (~a, ~b) --> ~min/max(a, b)
In the minimal case, this won't remove instructions, but it still improves
uses of existing values.

In the motivating example from PR35834, it does remove instructions, and
sets that case up to be optimized by something like D41603:
https://reviews.llvm.org/D41603

llvm-svn: 321936
2018-01-06 17:34:22 +00:00
Vedant Kumar b2ec02ba0b [Utils] Simplify salvageDebugInfo, NFCI
Having a single call to findDbgUsers() allows salvageDebugInfo() to
return earlier.

Differential Revision: https://reviews.llvm.org/D41787

llvm-svn: 321915
2018-01-05 23:27:02 +00:00
Sanjay Patel 5b6aacf2c1 [InstCombine] add folds for min(~a, b) --> ~max(a, b)
Besides the bug of omitting the inverse transform of max(~a, ~b) --> ~min(a, b),
the use checking and operand creation were off. We were potentially creating 
repeated identical instructions of existing values. This led to infinite
looping after I added the extra folds.

By using the simpler m_Not matcher and not creating new 'not' ops for a and b,
we avoid that problem. It's possible that not using IsFreeToInvert() here is
more limiting than the simpler matcher, but there are no tests for anything
more exotic. It's also possible that we should relax the use checking further
to handle a case like PR35834:
https://bugs.llvm.org/show_bug.cgi?id=35834
...but we can make that a follow-up if it is needed. 

llvm-svn: 321882
2018-01-05 19:01:17 +00:00
Peter Collingbourne 9110cb456d WholeProgramDevirt: Simplify ORE getter mechanism for old PM. NFCI.
llvm-svn: 321841
2018-01-05 00:27:51 +00:00
Reid Kleckner cd78ddc119 Revert "[JumpThreading] Preservation of DT and LVI across the pass"
This reverts r321825, it causes crashes in Chromium. Reproducer
forthcoming.

llvm-svn: 321832
2018-01-04 23:23:46 +00:00
Brian M. Rzycki cdad6c0b60 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 321825
2018-01-04 21:57:32 +00:00
Anna Thomas 9fca583757 Add assertion on DT availability during LI update in UpdateAnalysisInformation
This came up during discussions in llvm-commits for
rL321653: Check for unreachable preds before updating LI in
UpdateAnalysisInformation

The assert provides hints to passes to require both DT and LI if we plan on
updating LI through this function.

Tests run: make check

llvm-svn: 321805
2018-01-04 17:21:15 +00:00
Sanjay Patel c63f9014d6 [InstCombine] safely create a constant of the right type (PR35794)
llvm-svn: 321801
2018-01-04 14:31:56 +00:00
Aditya Kumar 1f90cae80f [GVNHoist] Fix: PR35222 gvn-hoist incorrectly erases load in case of a loop
Reviewers:
    dberlin
    sebpop
    eli.friedman

Differential Revision: https://reviews.llvm.org/D41453

llvm-svn: 321789
2018-01-04 07:47:24 +00:00
Matt Arsenault 8070882b4e StructurizeCFG: Fix broken backedge detection
The work order was changed in r228186 from SCC order
to RPO with an arbitrary sorting function. The sorting
function attempted to move inner loop nodes earlier. This
was was apparently relying on an assumption that every block
in a given loop / the same loop depth would be seen before
visiting another loop. In the broken testcase, a block
outside of the loop was encountered before moving onto
another block in the same loop. The testcase would then
structurize such that one blocks unconditional successor
could never be reached.

Revert to plain RPO for the analysis phase. This fixes
detecting edges as backedges that aren't really.

The processing phase does use another visited set, and
I'm unclear on whether the order there is as important.
An arbitrary order doesn't work, and triggers some infinite
loops. The reversed RPO list seems to work and is closer
to the order that was used before, minus the arbitary
custom sorting.

A few of the changed tests now produce smaller code,
and a few are slightly worse looking.

llvm-svn: 321751
2018-01-03 18:45:37 +00:00
Simon Pilgrim 3bf2d64589 [InstCombine] Check for out of range shift values using APInt before calling getZExtValue
Reduced from oss-fuzz #4871 test case

llvm-svn: 321748
2018-01-03 18:28:20 +00:00
Anna Thomas bdb9430917 [BasicBlockUtils] Check for unreachable preds before updating LI in UpdateAnalysisInformation
Summary:
We are incorrectly updating the LI when loop-simplify generates
dedicated exit blocks for a loop. The issue is that there's an implicit
assumption that the Preds passed into UpdateAnalysisInformation are
reachable. However, this is not true and breaks LI by incorrectly
updating the header of a loop.

One such case is when we generate dedicated exits when the exit block is
a landing pad (through SplitLandingPadPredecessors). There maybe other
cases as well, since we do not guarantee that Preds passed in are
reachable basic blocks.

The added test case shows how loop-simplify breaks LI for the outer loop (and DT in turn)
after we try to generate the LoopSimplifyForm.

Reviewers: davide, chandlerc, sanjoy

Reviewed By: davide

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41519

llvm-svn: 321653
2018-01-02 16:25:50 +00:00
Dmitry Venikov a58d8deb3a [InstCombine] Missed optimization in math expression: squashing sqrt functions
Summary: This patch enables folding under -ffast-math flag sqrt(a) * sqrt(b) -> sqrt(a*b)

Reviewers: hfinkel, spatel, davide

Reviewed By: spatel, davide

Subscribers: davide, llvm-commits

Differential Revision: https://reviews.llvm.org/D41322

llvm-svn: 321637
2018-01-02 05:58:11 +00:00
Davide Italiano 86b7949f62 [SimplifyCFG] Return to the pass manager the correct value.
I wanted to commit this with r321603, but I failed to squash
the two commits.

llvm-svn: 321606
2017-12-31 16:54:03 +00:00
Davide Italiano 0512bf5af2 [Utils/Local] Use `auto` when the type is obvious. NFCI.
llvm-svn: 321605
2017-12-31 16:51:50 +00:00
Davide Italiano 5dd1c587e7 [Utils] Remove commented debug message. NFCI.
llvm-svn: 321604
2017-12-31 16:48:44 +00:00
Davide Italiano 9f074fe915 [SimplifyCFG] Stop hoisting musttail calls incorrectly.
PR35774.

llvm-svn: 321603
2017-12-31 16:47:16 +00:00
Benjamin Kramer c7fc81e659 Use phi ranges to simplify code. No functionality change intended.
llvm-svn: 321585
2017-12-30 15:27:33 +00:00
Matt Arsenault 8dcfa137f3 StructurizeCFG: Use phi iterator range
llvm-svn: 321568
2017-12-29 19:25:57 +00:00
Benjamin Kramer 24cb28bb54 Remove superfluous copies in sample profiling.
No functionliaty change intended.

llvm-svn: 321530
2017-12-28 18:10:41 +00:00
Guozhi Wei 29697c13bc Revert r321377, it causes regression to https://reviews.llvm.org/P8055.
llvm-svn: 321528
2017-12-28 17:02:34 +00:00
Benjamin Kramer 3a13ed60ba Avoid int to string conversion in Twine or raw_ostream contexts.
Some output changes from uppercase hex to lowercase hex, no other functionality change intended.

llvm-svn: 321526
2017-12-28 16:58:54 +00:00
Max Kazantsev a13e163a27 [RewriteStatepoints] Fix incorrect assertion
`RewriteStatepointsForGC` iterates over function blocks and their predecessors
in order of declaration. One of outcomes of this is that callsites are placed in
arbitrary order which has nothing to do with travelsar order.

On the other hand, function `recomputeLiveInValues` asserts that bases are
added to `Info.PointerToBase` before their deried pointers are updated. But
if call sites are processed in order different from RPOT, this is not necessarily
true. We cannot guarantee that the base was placed there before every
pointer derived from it. All we can guarantee is that this base was marked as
known base by this point.

This patch replaces the fact that we assert from checking that the base was
added to the map with assert that the base was marked as known base.

Differential Revision: https://reviews.llvm.org/D41593

llvm-svn: 321517
2017-12-28 12:03:12 +00:00
Simon Pilgrim 472689a159 [InstCombine] Check for isa<Instruction> before using cast<>
Protects against casts from constexpr etc.

Reduced from oss-fuzz #4788 test case

llvm-svn: 321515
2017-12-28 09:35:35 +00:00
Reid Kleckner 6d31001cd6 Revert "[memcpyopt] Teach memcpyopt to optimize across basic blocks"
This reverts r321138. It seems there are still underlying issues with
memdep. PR35519 seems to still be present if debug info is enabled. We
end up losing a memcpy. Somehow during store to memset merging, we
insert the memset after the memcpy or fail to update the memdep analysis
to account for the newly inserted memset of a pair.

Reduced test case:

  #include <assert.h>
  #include <stdio.h>
  #include <string>
  #include <utility>
  #include <vector>

  void do_push_back(
      std::vector<std::pair<std::string, std::vector<std::string>>>* crls) {
    crls->push_back(std::make_pair(std::string(), std::vector<std::string>()));
  }

  int __attribute__((optnone)) main() {
    // Put some data in the vector and then remove it so we take the push_back
    // fast path.
    std::vector<std::pair<std::string, std::vector<std::string>>> crl_set;
    crl_set.push_back({"asdf", {}});
    crl_set.pop_back();
    printf("first word in vector storage: %p\n", *(void**)crl_set.data());

    // Do the push_back which may fail to initialize the data.
    do_push_back(&crl_set);
    auto* first = &crl_set.back().first;
    printf("first word in vector storage (should be zero): %p\n",
           *(void**)crl_set.data());
    assert(first->empty());
    puts("ok");
  }

Compile with libc++, enable optimizations, and enable debug info:
$ clang++ -stdlib=libc++ -g -O2 t.cpp -o t.exe -Wl,-rpath=llvm/build/lib

This program will assert with this change.

llvm-svn: 321510
2017-12-28 05:10:33 +00:00
Simon Pilgrim e7d032f1d8 [InstCombine] Gracefully handle out of range extractelement indices
InstSimplify is responsible for handling these, but we shouldn't just assert here.

Reduced from oss-fuzz #4808 test case

llvm-svn: 321489
2017-12-27 12:00:18 +00:00
Philip Reames cd13a66381 [instcombine] add powi(x, 2) -> x * x
llvm-svn: 321468
2017-12-27 01:30:12 +00:00
Philip Reames 5000ba69d7 Sink a couple of transforms from instcombine into instsimplify.
llvm-svn: 321467
2017-12-27 01:14:30 +00:00
Philip Reames 7a6db4fc4f [NFC] Extract out a helper function for SimplifyCall(CS, Q)
This simplifies code, but the real motivation is that it lets me clean up some downstream code.

llvm-svn: 321466
2017-12-27 00:16:12 +00:00
Zhaoshi Zheng 8af1e1cb78 [Unroll][DebugInfo] Propagate loop body's debug location to epilog preheader
NewExit and epilog PreHeader should has the same debug loc as the original loop
body, instead of original loop exit.

llvm-svn: 321465
2017-12-26 23:31:21 +00:00
Sanjay Patel 14adbacd8a [InstCombine] fix miscompile of frem with 0.0 operand (PR34870)
We might want to select NAN here or do this transform with fast-math,
but this should at least fix the miscompile.

llvm-svn: 321461
2017-12-26 22:12:20 +00:00
Benjamin Kramer 802e6255b2 Make helpers static. No functionality change.
llvm-svn: 321425
2017-12-24 12:46:22 +00:00
Florian Hahn 7e9328906b [CallSiteSplitting] Remove isOrHeader restriction.
By following the single predecessors of the predecessors of the call
site, we do not need to restrict the control flow.

Reviewed By: junbuml, davide

Differential Revision: https://reviews.llvm.org/D40729

llvm-svn: 321413
2017-12-23 20:02:26 +00:00
Davide Italiano 55b663431e [SCCP] Manually fold branches on undef.
This code was originally removed and replace with an assertion
because believed unnecessary. It turns out there was simply
no test coverage for this case, and the constant folder doesn't
yet know about patterns like `br undef %label1, %label2`.
Presumably at some point the constant folder might learn about
these patterns, but it's a broader change.
A testcase will be added to make sure this doesn't regress again
in the future.

Fixes PR35723.

llvm-svn: 321402
2017-12-23 15:06:30 +00:00
Guozhi Wei 33250340f4 [SimplifyCFG] Don't do if-conversion if there is a long dependence chain
If after if-conversion, most of the instructions in this new BB construct a long and slow dependence chain, it may be slower than cmp/branch, even if the branch has a high miss rate, because the control dependence is transformed into data dependence, and control dependence can be speculated, and thus, the second part can execute in parallel with the first part on modern OOO processor.

This patch checks for the long dependence chain, and give up if-conversion if find one.

Differential Revision: https://reviews.llvm.org/D39352

llvm-svn: 321377
2017-12-22 18:54:04 +00:00
Easwaran Raman a17f220590 Add hasProfileData() to check if a function has profile data. NFC.
Summary:
This replaces calls to getEntryCount().hasValue() with hasProfileData
that does the same thing. This refactoring is useful to do before adding
synthetic function entry counts but also a useful cleanup IMO even
otherwise. I have used hasProfileData instead of hasRealProfileData as
David had earlier suggested since I think profile implies "real" and I
use the phrase "synthetic entry count" and not "synthetic profile count"
but I am fine calling it hasRealProfileData if you prefer.

Reviewers: davidxl, silvas

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41461

llvm-svn: 321331
2017-12-22 01:33:52 +00:00
Michael Zolotukhin ad371e0caa [SimplifyCFG] Avoid quadratic on a predecessors number behavior in instruction sinking.
If a block has N predecessors, then the current algorithm will try to
sink common code to this block N times (whenever we visit a
predecessor). Every attempt to sink the common code includes going
through all predecessors, so the complexity of the algorithm becomes
O(N^2).
With this patch we try to sink common code only when we visit the block
itself. With this, the complexity goes down to O(N).
As a side effect, the moment the code is sunk is slightly different than
before (the order of simplifications has been changed), that's why I had
to adjust two tests (note that neither of the tests is supposed to test
SimplifyCFG):
* test/CodeGen/AArch64/arm64-jumptable.ll - changes in this test mimic
the changes that previous implementation of SimplifyCFG would do.
* test/CodeGen/ARM/avoid-cpsr-rmw.ll - in this test I disabled common
code sinking by a command line flag.

llvm-svn: 321236
2017-12-21 01:22:13 +00:00
Matthew Simpson cb35c5d5c2 [ICP] Expose unconditional call promotion interface
This patch modifies the indirect call promotion utilities by exposing and using
an unconditional call promotion interface. The unconditional promotion
interface (i.e., call promotion without creating an if-then-else) can be used
if it's known that an indirect call has only one possible callee. The existing
conditional promotion interface uses this unconditional interface to promote an
indirect call after it has been versioned and placed within the "then" block.

A consequence of unconditional promotion is that the fix-up operations for phi
nodes in the normal destination of invoke instructions are changed. This is
necessary because the existing implementation assumed that an invoke had been
versioned, creating a "merge" block where a return value bitcast could be
placed. In the new implementation, the edge between a promoted invoke's parent
block and its normal destination is split if needed to add a bitcast for the
return value. If the invoke is also versioned, the phi node merging the return
value of the promoted and original invoke instructions is placed in the "merge"
block.

Differential Revision: https://reviews.llvm.org/D40751

llvm-svn: 321210
2017-12-20 19:26:37 +00:00
Evgeniy Stepanov 3fd1b1a764 [hwasan] Implement -fsanitize-recover=hwaddress.
Summary: Very similar to AddressSanitizer, with the exception of the error type encoding.

Reviewers: kcc, alekseyshl

Subscribers: cfe-commits, kubamracek, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D41417

llvm-svn: 321203
2017-12-20 19:05:44 +00:00
Florian Hahn 012c8f97b2 [InstCombine] Add debug location to new caller.
Reviewers: rnk, aprantl, majnemer

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D414

llvm-svn: 321191
2017-12-20 17:16:59 +00:00
Mohammad Shahid 3a934d6ab9 Revert r320548:[SLP] Vectorize jumbled memory loads
llvm-svn: 321181
2017-12-20 15:26:59 +00:00
Florian Hahn 467abe3e4f [LV] Remove unnecessary DoExtraAnalysis guard (silent bug)
canVectorize is only checking if the loop has a normalized pre-header if DoExtraAnalysis is true.
This doesn't make sense to me because reporting analysis information shouldn't alter legality
checks. This is probably the result of a last minute minor change before committing (?).

Patch by Diego Caballero.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D40973

llvm-svn: 321172
2017-12-20 13:28:38 +00:00
Dan Gohman aa3922819e [memcpyopt] Teach memcpyopt to optimize across basic blocks
This teaches memcpyopt to make a non-local memdep query when a local query
indicates that the dependency is non-local. This notably allows it to
eliminate many more llvm.memcpy calls in common Rust code, often by 20-30%.

This is r319482 and r319483, along with fixes for PR35519: fix the 
optimization that merges stores into memsets to preserve cached memdep
info, and fix memdep's non-local caching strategy to not assume that larger
queries are always more conservative than smaller ones.

Fixes PR28958 and PR35519.

Differential Revision: https://reviews.llvm.org/D40802

llvm-svn: 321138
2017-12-20 01:36:25 +00:00
Adrian Prantl 0e6694d111 Silence a bunch of implicit fallthrough warnings
llvm-svn: 321114
2017-12-19 22:05:25 +00:00
Haicheng Wu 5b106ef92e [SeparateConstOffsetFromGEP] Fix a typo. NFC.
do CSE for to => do CSE to

llvm-svn: 321098
2017-12-19 18:49:21 +00:00
Max Kazantsev fd95ee0c9a [JumpThreading] Restrict PRE across instructions that don't pass control to successors
PRE in JumpThreading should not be able to hoist copy of non-speculable loads across
instructions that don't always transfer execution to their successors, otherwise they may
introduce an unsafe load which otherwise would not be executed.

The same problem for GVN was fixed as rL316975.

Differential Revision: https://reviews.llvm.org/D40347

llvm-svn: 321063
2017-12-19 09:10:21 +00:00
Teresa Johnson 915897e21b [PGO] Fix handling of cold entry count for instrumented PGO
Summary:
In r277849, getEntryCount was changed to return None when the entry
count was 0, specifically for SamplePGO where it means no samples were
recorded. However, for instrumentation PGO a 0 entry count should be
returned directly, since it does mean that the function was completely
cold. Otherwise we end up treating these functions conservatively
in isFunctionEntryCold() and isColdBB().

Instead, for SamplePGO use -1 when there are no samples, and change
getEntryCount to return None when the value is -1.

Reviewers: danielcdh, davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41307

llvm-svn: 321018
2017-12-18 20:02:43 +00:00
Dimitry Andric e4f5d01033 Fix more inconsistent line endings. NFC.
llvm-svn: 321016
2017-12-18 19:46:56 +00:00
Matt Arsenault d89d0b6494 Removed unused DominanceFrontier
llvm-svn: 321001
2017-12-18 18:01:13 +00:00
Xinliang David Li 19fb5b467b [PGO] add MST min edge selection heuristic to ensure non-zero entry count
Differential Revision: http://reviews.llvm.org/D41059

llvm-svn: 320998
2017-12-18 17:56:19 +00:00
Sean Fertile 5fb624a3b8 [Memcpy Loop Lowering] Remove the fixed int8 lowering.
Switch over to the lowering that uses target supplied operand types.

Differential Revision: https://reviews.llvm.org/D41201

llvm-svn: 320989
2017-12-18 15:31:14 +00:00
Eugene Leviant c95b49603e [ThinLTO] Remove unused code
This is a re-commit of r320464, after patch for gold plugin
was landed.

llvm-svn: 320968
2017-12-18 10:53:45 +00:00
Hiroshi Inoue c6faf15459 [SROA] Disable non-whole-alloca splits by default
This patch introduce a switch to control splitting of non-whole-alloca slices with default off.
The switch will be default on again after fixing an issue reported in PR35657.

llvm-svn: 320958
2017-12-18 06:47:37 +00:00
Sean Fertile 68d7f9da76 [Memcpy Loop Lowering] Only calculate residual size/bytes copied when needed.
If the loop operand type is int8 then there will be no residual loop for the
unknown size expansion. Dont create the residual-size and bytes-copied values
when they are not needed.

llvm-svn: 320929
2017-12-16 22:41:39 +00:00
Sanjay Patel 5a0cdac174 [InstCombine] canonicalize shifty abs(): ashr+add+xor --> cmp+neg+sel
We want to do this for 2 reasons:
1. Value tracking does not recognize the ashr variant, so it would fail to match for cases like D39766.
2. DAGCombiner does better at producing optimal codegen when we have the cmp+sel pattern.

More detail about what happens in the backend:
1. DAGCombiner has a generic transform for all targets to convert the scalar cmp+sel variant of abs 
   into the shift variant. That is the opposite of this IR canonicalization.
2. DAGCombiner has a generic transform for all targets to convert the vector cmp+sel variant of abs 
   into either an ABS node or the shift variant. That is again the opposite of this IR canonicalization.
3. DAGCombiner has a generic transform for all targets to convert the exact shift variants produced by #1 or #2
   into an ISD::ABS node. Note: It would be an efficiency improvement if we had #1 go directly to an ABS node 
   when that's legal/custom.
4. The pattern matching above is incomplete, so it is possible to escape the intended/optimal codegen in a 
   variety of ways.
   a. For #2, the vector path is missing the case for setlt with a '1' constant.
   b. For #3, we are missing a match for commuted versions of the shift variants.
5. Therefore, this IR canonicalization can only help get us to the optimal codegen. The version of cmp+sel 
   produced by this patch will be recognized in the DAG and converted to an ABS node when possible or the 
   shift sequence when not.
6. In the following examples with this patch applied, we may get conditional moves rather than the shift 
   produced by the generic DAGCombiner transforms. The conditional move is created using a target-specific 
   decision for any given target. Whether it is optimal or not for a particular subtarget may be up for debate.

define i32 @abs_shifty(i32 %x) {
  %signbit = ashr i32 %x, 31 
  %add = add i32 %signbit, %x  
  %abs = xor i32 %signbit, %add 
  ret i32 %abs
}

define i32 @abs_cmpsubsel(i32 %x) {
  %cmp = icmp slt i32 %x, zeroinitializer
  %sub = sub i32 zeroinitializer, %x
  %abs = select i1 %cmp, i32 %sub, i32 %x
  ret i32 %abs
}

define <4 x i32> @abs_shifty_vec(<4 x i32> %x) {
  %signbit = ashr <4 x i32> %x, <i32 31, i32 31, i32 31, i32 31> 
  %add = add <4 x i32> %signbit, %x  
  %abs = xor <4 x i32> %signbit, %add 
  ret <4 x i32> %abs
}

define <4 x i32> @abs_cmpsubsel_vec(<4 x i32> %x) {
  %cmp = icmp slt <4 x i32> %x, zeroinitializer
  %sub = sub <4 x i32> zeroinitializer, %x
  %abs = select <4 x i1> %cmp, <4 x i32> %sub, <4 x i32> %x
  ret <4 x i32> %abs
}

> $ ./opt -instcombine shiftyabs.ll -S | ./llc -o - -mtriple=x86_64 -mattr=avx 
> abs_shifty:
> 	movl	%edi, %eax
> 	negl	%eax
> 	cmovll	%edi, %eax
> 	retq
> 
> abs_cmpsubsel:
> 	movl	%edi, %eax
> 	negl	%eax
> 	cmovll	%edi, %eax
> 	retq
> 
> abs_shifty_vec:
> 	vpabsd	%xmm0, %xmm0
> 	retq
> 
> abs_cmpsubsel_vec:
> 	vpabsd	%xmm0, %xmm0
> 	retq
> 
> $ ./opt -instcombine shiftyabs.ll -S | ./llc -o - -mtriple=aarch64
> abs_shifty:
> 	cmp	w0, #0                  // =0
> 	cneg	w0, w0, mi
> 	ret
> 
> abs_cmpsubsel: 
> 	cmp	w0, #0                  // =0
> 	cneg	w0, w0, mi
> 	ret
>                                        
> abs_shifty_vec: 
> 	abs	v0.4s, v0.4s
> 	ret
> 
> abs_cmpsubsel_vec: 
> 	abs	v0.4s, v0.4s
> 	ret
> 
> $ ./opt -instcombine shiftyabs.ll -S | ./llc -o - -mtriple=powerpc64le 
> abs_shifty:  
> 	srawi 4, 3, 31
> 	add 3, 3, 4
> 	xor 3, 3, 4
> 	blr
> 
> abs_cmpsubsel:
> 	srawi 4, 3, 31
> 	add 3, 3, 4
> 	xor 3, 3, 4
> 	blr
> 
> abs_shifty_vec:   
> 	vspltisw 3, -16
> 	vspltisw 4, 15
> 	vsubuwm 3, 4, 3
> 	vsraw 3, 2, 3
> 	vadduwm 2, 2, 3
> 	xxlxor 34, 34, 35
> 	blr
> 
> abs_cmpsubsel_vec: 
> 	vspltisw 3, -16
> 	vspltisw 4, 15
> 	vsubuwm 3, 4, 3
> 	vsraw 3, 2, 3
> 	vadduwm 2, 2, 3
> 	xxlxor 34, 34, 35
> 	blr
>

Differential Revision: https://reviews.llvm.org/D40984

llvm-svn: 320921
2017-12-16 16:41:17 +00:00
Hal Finkel 5444f40965 [LV] Extend InstWidening with CM_Widen_Recursive
Changes to the original scalar loop during LV code gen cause the return value
of Legal->isConsecutivePtr() to be inconsistent with the return value during
legal/cost phases (further analysis and information of the bug is in D39346).
This patch is an alternative fix to PR34965 following the CM_Widen approach
proposed by Ayal and Gil in D39346. It extends InstWidening enum with
CM_Widen_Reverse to properly record the widening decision for consecutive
reverse memory accesses and, consequently, get rid of the
Legal->isConsetuviePtr() call in LV code gen. I think this is a simpler/cleaner
solution to PR34965 than the one in D39346.

Fixes PR34965.

Patch by Diego Caballero, thanks!

Differential Revision: https://reviews.llvm.org/D40742

llvm-svn: 320913
2017-12-16 02:55:24 +00:00
Hal Finkel 2ff24731bb [SimplifyLibCalls] Inline calls to cabs when it's safe to do so
When unsafe algerbra is allowed calls to cabs(r) can be replaced by:

  sqrt(creal(r)*creal(r) + cimag(r)*cimag(r))

Patch by Paul Walker, thanks!

Differential Revision: https://reviews.llvm.org/D40069

llvm-svn: 320901
2017-12-16 01:26:25 +00:00
Hal Finkel 7333aa9f16 [LV] NFC patch for moving VP*Recipe class definitions from LoopVectorize.cpp to VPlan.h
This is a small step forward to move VPlan stuff to where it should belong (i.e., VPlan.*):

  1. VP*Recipe classes in LoopVectorize.cpp are moved to VPlan.h.
  2. Many of VP*Recipe::print() and execute() definitions are still left in
     LoopVectorize.cpp since they refer to things declared in LoopVectorize.cpp. To
     be moved to VPlan.cpp at a later time.
  3. InterleaveGroup class is moved from anonymous namespace to llvm namespace.
     Referencing it in anonymous namespace from VPlan.h ended up in warning.

Patch by Hideki Saito, thanks!

Differential Revision: https://reviews.llvm.org/D41045

llvm-svn: 320900
2017-12-16 01:12:50 +00:00
Teresa Johnson 69b2de8466 Fix NDEBUG build problem in r320895
Fix incorrect placement of #endif causing NDEBUG build failures.

llvm-svn: 320897
2017-12-16 00:29:31 +00:00
Teresa Johnson 81bbf74265 [ThinLTO] Enable importing of aliases as copy of aliasee
Summary:
This implements a missing feature to allow importing of aliases, which
was previously disabled because alias cannot be available_externally.
We instead import an alias as a copy of its aliasee.

Some additional work was required in the IndexBitcodeWriter for the
distributed build case, to ensure that the aliasee has a value id
in the distributed index file (i.e. even when it is not being
imported directly).

This is a performance win in codes that have many aliases, e.g. C++
applications that have many constructor and destructor aliases.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D40747

llvm-svn: 320895
2017-12-16 00:18:12 +00:00
Jun Bum Lim 44c58d35c1 Re-commit : [LICM] Allow sinking when foldable in loop
This recommits r320823 reverted due to the test failure in sink-foldable.ll and
an unused variable. Added "REQUIRES: aarch64-registered-target" in the test
and removed unused variable.

Original commit message:

  Continue trying to sink an instruction if its users in the loop is foldable.
  This will allow the instruction to be folded in the loop by decoupling it from
  the user outside of the loop.

  Reviewers: hfinkel, majnemer, davidxl, efriedma, danielcdh, bmakam, mcrosier

  Reviewed By: hfinkel

  Subscribers: javed.absar, bmakam, mcrosier, llvm-commits

  Differential Revision: https://reviews.llvm.org/D37076

llvm-svn: 320858
2017-12-15 20:33:24 +00:00
Sean Fertile 42b13343fd [Memcpy Loop Lowering] Insert loop BB inbetween the split BB.
The original memcpy expansion inserted the loop basic block inbetween
the 2 new basic blocks created by splitting the original block the memcpy
call was in. This commit makes the new memcpy expansion do the same to keep the
layout of the IR matching between the old and new implementations.

Differential Review: https://reviews.llvm.org/D41197

llvm-svn: 320848
2017-12-15 19:29:12 +00:00
Sanjay Patel c722e26549 fix typo in comment and remove inaccurate comment; NFC
llvm-svn: 320838
2017-12-15 18:25:13 +00:00
Jun Bum Lim 5efd4d8b5e Revert "Re-commit : [LICM] Allow sinking when foldable in loop"
This reverts commit r320833.

llvm-svn: 320836
2017-12-15 18:12:49 +00:00
Jun Bum Lim 83ccad6684 Re-commit : [LICM] Allow sinking when foldable in loop
This recommit r320823 after fixing a test failure.

 Original commit message:

    Continue trying to sink an instruction if its users in the loop is foldable.
    This will allow the instruction to be folded in the loop by decoupling it from
    the user outside of the loop.

    Reviewers: hfinkel, majnemer, davidxl, efriedma, danielcdh, bmakam, mcrosier

    Reviewed By: hfinkel

    Subscribers: javed.absar, bmakam, mcrosier, llvm-commits

    Differential Revision: https://reviews.llvm.org/D37076

llvm-svn: 320833
2017-12-15 17:58:59 +00:00
Jun Bum Lim 6136d87f5d Revert "[LICM] Allow sinking when foldable in loop"
This reverts commit r320823.

llvm-svn: 320828
2017-12-15 16:35:09 +00:00
Jun Bum Lim 22855c26a5 [LICM] Allow sinking when foldable in loop
Summary:
Continue trying to sink an instruction if its users in the loop is foldable.
This will allow the instruction to be folded in the loop by decoupling it from
the user outside of the loop.

Reviewers: hfinkel, majnemer, davidxl, efriedma, danielcdh, bmakam, mcrosier

Reviewed By: hfinkel

Subscribers: javed.absar, bmakam, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D37076

llvm-svn: 320823
2017-12-15 16:09:54 +00:00
Fedor Sergeev 4b86d79048 [PM] port Rewrite Statepoints For GC to the new pass manager.
Summary:
The port is nearly straightforward.
The only complication is related to the analyses handling,
since one of the analyses used in this module pass is domtree,
which is a function analysis. That requires asking for the results
of each function and disallows a single interface for run-on-module
pass action.

Decided to copy-paste the main body of this pass.
Most of its code is requesting analyses anyway, so not that much
of a copy-paste.

The rest of the code movement is to transform all the implementation
helper functions like stripNonValidData into non-member statics.

Extended all the related LLVM tests with new-pass-manager use.
No failures.

Reviewers: sanjoy, anna, reames

Reviewed By: anna

Subscribers: skatkov, llvm-commits

Differential Revision: https://reviews.llvm.org/D41162

llvm-svn: 320796
2017-12-15 09:32:11 +00:00
Sanjay Patel 0ab0c1a201 [SimplifyCFG] don't sink common insts too soon (PR34603)
This should solve:
https://bugs.llvm.org/show_bug.cgi?id=34603
...by preventing SimplifyCFG from altering redundant instructions before early-cse has a chance to run.
It changes the default (canonical-forming) behavior of SimplifyCFG, so we're only doing the
sinking transform later in the optimization pipeline.

Differential Revision: https://reviews.llvm.org/D38566

llvm-svn: 320749
2017-12-14 22:05:20 +00:00
Guozhi Wei d22d1b953d [SLPVectorizer] Don't ignore scalar extraction instructions of aggregate value
In SLPVectorizer, the vector build instructions (insertvalue for aggregate type) is passed to BoUpSLP.buildTree, it is treated as UserIgnoreList, so later in cost estimation, the cost of these instructions are not counted. 
For aggregate value, later usage are more likely to be done in scalar registers, either used as individual scalars or used as a whole for function call or return value. Ignore scalar extraction instructions may cause too aggressive vectorization for aggregate values, and slow down performance. So for vectorization of aggregate value, the scalar extraction instructions are required in cost estimation.

Differential Revision: https://reviews.llvm.org/D41139

llvm-svn: 320736
2017-12-14 19:35:43 +00:00
Fedor Sergeev 83bcc68afa [PM][InstCombine] fixing omission of AliasAnalysis in new-pass-manager's version of InstCombine
Summary:
Passing AliasAnalysis results instead of nullptr appears to work just fine.
A couple new-pass-manager tests updated to align with new order of analyses.

Reviewers: chandlerc, spatel, craig.topper

Reviewed By: chandlerc

Subscribers: mehdi_amini, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D41203

llvm-svn: 320687
2017-12-14 10:36:31 +00:00
Dorit Nuzman 4750c785b3 [LV] Support efficient vectorization of an induction with redundant casts
D30041 extended SCEVPredicateRewriter to improve handling of Phi nodes whose
update chain involves casts; PSCEV can now build an AddRecurrence for some
forms of such phi nodes, under the proper runtime overflow test. This means
that we can identify such phi nodes as an induction, and the loop-vectorizer
can now vectorize such inductions, however inefficiently. The vectorizer
doesn't know that it can ignore the casts, and so it vectorizes them.

This patch records the casts in the InductionDescriptor, so that they could
be marked to be ignored for cost calculation (we use VecValuesToIgnore for
that) and ignored for vectorization/widening/scalarization (i.e. treated as
TriviallyDead).

In addition to marking all these casts to be ignored, we also need to make
sure that each cast is mapped to the right vector value in the vector loop body
(be it a widened, vectorized, or scalarized induction). So whenever an
induction phi is mapped to a vector value (during vectorization/widening/
scalarization), we also map the respective cast instruction (if exists) to that
vector value. (If the phi-update sequence of an induction involves more than one
cast, then the above mapping to vector value is relevant only for the last cast
of the sequence as we allow only the "last cast" to be used outside the
induction update chain itself).

This is the last step in addressing PR30654.

llvm-svn: 320672
2017-12-14 07:56:31 +00:00
Sanjay Patel 558a465473 [EarlyCSE] recognize swapped variants of abs/nabs as equivalent
Extends https://reviews.llvm.org/rL320640

Differential Revision: https://reviews.llvm.org/D41136

llvm-svn: 320653
2017-12-13 22:57:35 +00:00
Brian M. Rzycki 580bc3c8fa Reverting [JumpThreading] Preservation of DT and LVI across the pass
Stage 2 bootstrap failed:
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules-2/builds/14434

llvm-svn: 320641
2017-12-13 22:01:17 +00:00
Sanjay Patel 3c7a35de7f [EarlyCSE] recognize commuted and swapped variants of min/max as equivalent (PR35642)
As shown in:
https://bugs.llvm.org/show_bug.cgi?id=35642
...we can have different forms of min/max, so we should recognize those here in EarlyCSE 
similar to how we already handle binops and compares that can commute.

Differential Revision: https://reviews.llvm.org/D41136

llvm-svn: 320640
2017-12-13 21:58:15 +00:00
Michael Zolotukhin 6af4f232b5 Remove redundant includes from lib/Transforms.
llvm-svn: 320628
2017-12-13 21:31:01 +00:00