Commit Graph

108 Commits

Author SHA1 Message Date
Florian Hahn a6e63f176c [NewGVN] Fix handling of assumes
This patch fixes two bugs:

* test1: Previously assume(a >= 5) concluded that a == 5. That's only
         valid for assume(a == 5)...
* test2: If operands were swapped, additional users were added to the
         wrong cmp operand. This resulted in an "unsettled iteration"
         assertion failure.

Patch by Nikita Popov

Differential Revision: https://reviews.llvm.org/D46974

llvm-svn: 333007
2018-05-22 17:38:22 +00:00
Piotr Padlewski ce358262eb Dissallow non-empty metadata for invariant.group
Summary:
This feature is not needed, but it might be usefull in the future
to use metadata to mark what which function should support it
(and strip it when not).

Reviewers: rsmith, sanjoy, amharc, kuhar

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45419

llvm-svn: 332787
2018-05-18 23:53:46 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Piotr Padlewski 5dde809404 Rename invariant.group.barrier to launder.invariant.group
Summary:
This is one of the initial commit of "RFC: Devirtualization v2" proposal:
https://docs.google.com/document/d/16GVtCpzK8sIHNc2qZz6RN8amICNBtvjWUod2SujZVEo/edit?usp=sharing

Reviewers: rsmith, amharc, kuhar, sanjoy

Subscribers: arsenm, nhaehnle, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45111

llvm-svn: 331448
2018-05-03 11:03:01 +00:00
Florian Hahn 773872fd67 [NewGVN] Split OpPHI detection and creation.
It also adds a check making sure PHIs for operands are all in the same
block.

Patch by Daniel Berlin <dberlin@dberlin.org>

Reviewers: dberlin, davide

Differential Revision: https://reviews.llvm.org/D43865

llvm-svn: 330444
2018-04-20 16:37:13 +00:00
Florian Hahn b789165e6b [NewGVN] Add ops as dependency if we cannot find a leader for ValueOp.
If those operands change, we might find a leader for ValueOp, which
could enable new phi-of-op creation.

This fixes a case where we missed creating a phi-of-ops node. With D43865
and this patch, bootstrapping clang/llvm works with -enable-newgvn, whereas
without it, the "value changed after iteration" assertion is triggered.

Reviewers: dberlin, davide

Reviewed By: dberlin

Differential Revision: https://reviews.llvm.org/D42180

llvm-svn: 330334
2018-04-19 15:05:47 +00:00
Florian Hahn 9a175bc1bc Remove file accidentally added in r330320.
llvm-svn: 330321
2018-04-19 12:09:05 +00:00
Florian Hahn 2342533e1a [IR/BasicBlockTest] Fix asan failure introduced in rL330316.
The argument has to be deleted after the module containing the function
gets deleted.

llvm-svn: 330320
2018-04-19 12:06:26 +00:00
Piotr Padlewski ac5abbfdd9 NFC: Update NewGVN invariant.group test
llvm-svn: 329533
2018-04-08 16:04:09 +00:00
Sanjay Patel 4ad3c32144 [InstCombine, NewGVN] remove FP undef from tests
I'm trying to preserve the intent of these tests by using 
non-undef operands; if we fix FP undef folding these tests
will not pass.

llvm-svn: 327004
2018-03-08 14:57:08 +00:00
Florian Hahn 1807c516c7 [NewGVN] Update phi-of-ops def block when updating existing ValuePHI.
In case we update a ValuePHI node created earlier, we could update it
based on a different OpPHI which could be in a different block.
We need to update the TempToBlock mapping reflecting the new block,
otherwise we would end up placing the new phi node in a wrong block.

This problem is exposed by the test case in
https://bugs.llvm.org/show_bug.cgi?id=36504.

This patch fixes a slightly simpler problem than in the bug report. In
the bug's re-producer, the additional problem is that we are re-using a
ValuePHI node with to few incoming values for the new OpPHI. If this
patch makes sense, I will follow it up with a patch that creates a new
PHI node if the existing PHI node has a different number of incoming
values.

Reviewers: davide, dberlin

Reviewed By: dberlin

Differential Revision: https://reviews.llvm.org/D43770

llvm-svn: 326181
2018-02-27 09:34:51 +00:00
Daniel Neilson 1e68724d24 Remove alignment argument from memcpy/memmove/memset in favour of alignment attributes (Step 1)
Summary:
 This is a resurrection of work first proposed and discussed in Aug 2015:
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
and initially landed (but then backed out) in Nov 2015:
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

 The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

 This change is the first in a series that allows source and dest to each
have their own alignments by using the alignment attribute on their arguments.

 In this change we:
1) Remove the alignment argument.
2) Add alignment attributes to the source & dest arguments. We, temporarily,
   require that the alignments for source & dest be equal.

 For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

 Downstream users may have to update their lit tests that check for
@llvm.memcpy/memmove/memset call/declaration patterns. The following extended sed script
may help with updating the majority of your tests, but it does not catch all possible
patterns so some manual checking and updating will be required.

s~declare void @llvm\.mem(set|cpy|move)\.p([^(]*)\((.*), i32, i1\)~declare void @llvm.mem\1.p\2(\3, i1)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* \3, i8 \4, i8 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* \3, i8 \4, i16 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* \3, i8 \4, i32 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* \3, i8 \4, i64 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* \3, i8 \4, i128 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* align \6 \3, i8 \4, i8 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* align \6 \3, i8 \4, i16 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* align \6 \3, i8 \4, i32 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* align \6 \3, i8 \4, i64 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* align \6 \3, i8 \4, i128 \5, i1 \7)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* \4, i8\5* \6, i8 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* \4, i8\5* \6, i16 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* \4, i8\5* \6, i32 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* \4, i8\5* \6, i64 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* \4, i8\5* \6, i128 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* align \8 \4, i8\5* align \8 \6, i8 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* align \8 \4, i8\5* align \8 \6, i16 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* align \8 \4, i8\5* align \8 \6, i32 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* align \8 \4, i8\5* align \8 \6, i64 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* align \8 \4, i8\5* align \8 \6, i128 \7, i1 \9)~g

 The remaining changes in the series will:
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
   source and dest alignments.
Step 3) Update Clang to use the new IRBuilder API.
Step 4) Update Polly to use the new IRBuilder API.
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
        and those that use use MemIntrinsicInst::[get|set]Alignment() to use
        getDestAlignment() and getSourceAlignment() instead.
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
        MemIntrinsicInst::[get|set]Alignment() methods.

Reviewers: pete, hfinkel, lhames, reames, bollu

Reviewed By: reames

Subscribers: niosHD, reames, jholewinski, qcolombet, jfb, sanjoy, arsenm, dschuff, dylanmckay, mehdi_amini, sdardis, nemanjai, david2050, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, llvm-commits

Differential Revision: https://reviews.llvm.org/D41675

llvm-svn: 322965
2018-01-19 17:13:12 +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
Ivan A. Kosarev a80c79b5bf [Analysis] Generate more precise TBAA tags when one access encloses the other
There are cases when two tags with different base types denote
accesses to the same direct or indirect member of a structure
type. Currently, merging of such tags results in a tag that
represents an access to an object that has the type of that
member. This patch changes this so that if one of the accesses
encloses the other, then the generic tag is the one of the
enclosed access.

Differential Revision: https://reviews.llvm.org/D39557

llvm-svn: 321019
2017-12-18 20:05:20 +00:00
Evgeniy Stepanov c667c1f47a Hardware-assisted AddressSanitizer (llvm part).
Summary:
This is LLVM instrumentation for the new HWASan tool. It is basically
a stripped down copy of ASan at this point, w/o stack or global
support. Instrumenation adds a global constructor + runtime callbacks
for every load and store.

HWASan comes with its own IR attribute.

A brief design document can be found in
clang/docs/HardwareAssistedAddressSanitizerDesign.rst (submitted earlier).

Reviewers: kcc, pcc, alekseyshl

Subscribers: srhines, mehdi_amini, mgorny, javed.absar, eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D40932

llvm-svn: 320217
2017-12-09 00:21:41 +00:00
Dan Gohman 2c74fe977d Add an @llvm.sideeffect intrinsic
This patch implements Chandler's idea [0] for supporting languages that
require support for infinite loops with side effects, such as Rust, providing
part of a solution to bug 965 [1].

Specifically, it adds an `llvm.sideeffect()` intrinsic, which has no actual
effect, but which appears to optimization passes to have obscure side effects,
such that they don't optimize away loops containing it. It also teaches
several optimization passes to ignore this intrinsic, so that it doesn't
significantly impact optimization in most cases.

As discussed on llvm-dev [2], this patch is the first of two major parts.
The second part, to change LLVM's semantics to have defined behavior
on infinite loops by default, with a function attribute for opting into
potential-undefined-behavior, will be implemented and posted for review in
a separate patch.

[0] http://lists.llvm.org/pipermail/llvm-dev/2015-July/088103.html
[1] https://bugs.llvm.org/show_bug.cgi?id=965
[2] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118632.html

Differential Revision: https://reviews.llvm.org/D38336

llvm-svn: 317729
2017-11-08 21:59:51 +00:00
Davide Italiano 834b45129b [NewGVN] Stop assuming PHI args ordering when looking at phi-of-ops.
It's not guaranteed. There's a bug open to sort them in predecessor
order, but it won't happen anytime soon. In the meanwhile, passes
will have to do an O(#preds) scan. Such is life.

llvm-svn: 316953
2017-10-30 20:20:16 +00:00
Daniel Berlin d36c27bedb NewGVN: Fix PR 34473, by not using ExactlyEqualsExpression for finding
phi of ops users.

llvm-svn: 314612
2017-09-30 23:51:55 +00:00
Daniel Berlin c1305af09b NewGVN: Evaluate phi of ops expressions before creating phi node
llvm-svn: 314611
2017-09-30 23:51:54 +00:00
Daniel Berlin 9b926e90d3 NewGVN: Allow dependent PHI of ops
llvm-svn: 314610
2017-09-30 23:51:53 +00:00
Daniel Berlin f9c9455d3f NewGVN: Fix PR 34430 - we need to look through predicateinfo copies to detect self-cycles of phi nodes. We also need to not ignore certain types of arguments when testing whether the phi has a backedge or was originally constant.
llvm-svn: 312510
2017-09-05 02:17:43 +00:00
Daniel Berlin 54a92fcc5d NewGVN: Fix PR 34452 by passing instruction all the way down when we do aggregate value simplification
llvm-svn: 312509
2017-09-05 02:17:42 +00:00
Daniel Berlin 94090dd13b Fix PR/33305. caused by trying to simplify expressions in phi of ops that should have no leaders.
Summary:
After a discussion with Rekka, i believe this (or a small variant)
should fix the remaining phi-of-ops problems.

Rekka's algorithm for completeness relies on looking up expressions
that should have no leader, and expecting it to fail (IE looking up
expressions that can't exist in a predecessor, and expecting it to
find nothing).

Unfortunately, sometimes these expressions can be simplified to
constants, but we need the lookup to fail anyway.  Additionally, our
simplifier outsmarts this by taking these "not quite right"
expressions, and simplifying them into other expressions or walking
through phis, etc.  In the past, we've sometimes been able to find
leaders for these expressions, incorrectly.

This change causes us to not to try to phi of ops such expressions.
We determine safety by seeing if they depend on a phi node in our
block.

This is not perfect, we can do a bit better, but this should be a
"correctness start" that we can then improve.  It also requires a
bunch of caching that i'll eventually like to eliminate.

The right solution, longer term, to the simplifier issues, is to make
the query interface for the instruction simplifier/constant folder
have the flags we need, so that we can keep most things going, but
turn off the possibly-invalid parts (threading through phis, etc).
This is an issue in another wrong code bug as well.

Reviewers: davide, mcrosier

Subscribers: sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D37175

llvm-svn: 312401
2017-09-02 02:18:44 +00:00
Daniel Berlin 86932104db NewGVN: Make sure we don't incorrectly use PredicateInfo when doing PHI of ops
Summary: When we backtranslate expressions, we can't use the predicateinfo, since we are evaluating them in a different context.

Reviewers: davide, mcrosier

Subscribers: sanjoy, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D37174

llvm-svn: 312352
2017-09-01 19:20:18 +00:00
Daniel Berlin de269f4620 NewGVN: Fix PR33204 - We need to add memory users when we bypass memorydefs for loads, not just when we do it for stores.
llvm-svn: 311829
2017-08-26 07:37:11 +00:00
Daniel Berlin f948603a15 NewGVN: We weren't properly simplifying selects with equal arguments due to a thinko.
llvm-svn: 311626
2017-08-24 02:43:17 +00:00
Sam Elliott b0c9753691 Keep Optimization Remark Yaml in NewPM
Summary:
The New Pass Manager infrastructure was forgetting to keep around the optimization remark yaml file that the compiler might have been producing. This meant setting the option to '-' for stdout worked, but setting it to a filename didn't give file output (presumably it was deleted because compilation didn't explicitly keep it). This change just ensures that the file is kept if compilation succeeds.

So far I have updated one of the optimization remark output tests to add a version with the new pass manager. It is my intention for this patch to also include changes to all tests that use `-opt-remark-output=` but I wanted to get the code patch ready for review while I was making all those changes.

Fixes https://bugs.llvm.org/show_bug.cgi?id=33951

Reviewers: anemet, chandlerc

Reviewed By: anemet, chandlerc

Subscribers: javed.absar, chandlerc, fhahn, llvm-commits

Differential Revision: https://reviews.llvm.org/D36906

llvm-svn: 311271
2017-08-20 01:30:45 +00:00
Chad Rosier a5508e3119 [NewGVN] Add CL option to control the generation of phi-of-ops (disable by default).
Differential Revision: https://reviews.llvm.org/D36478539

llvm-svn: 310594
2017-08-10 14:12:57 +00:00
Davide Italiano 5974c31d91 [NewGVN] Fix the case where we have a phi-of-ops which goes away.
Patch by Daniel Berlin, fixes PR33196 (and probably something else).

llvm-svn: 309988
2017-08-03 21:17:49 +00:00
Davide Italiano 393a5dac6a [NewGVN] Now that load coercion is enable, we pass this test.
llvm-svn: 309872
2017-08-02 19:47:37 +00:00
Davide Italiano ee1c82112e [NewGVN] Check for congruency of memory accesses.
This is fine as nothing in the code relies on leader and memory
leader being the same for a given congruency class. Ack'ed by
Dan.

Fixes PR33720.

llvm-svn: 307699
2017-07-11 19:49:12 +00:00
Daniel Berlin 36b08b2088 NewGVN: Fix PR 33461, caused by slightly overzealous verification.
llvm-svn: 305657
2017-06-19 00:24:00 +00:00
Daniel Berlin eafdd862e5 NewGVN: Fix PR/33187. This is a bug caused by two things:
1. When there is no perfect iteration order, we can't let phi nodes
put themselves in terms of things that come later in the iteration
order, or we will endlessly cycle (the normal RPO algorithm clears the
hashtable to avoid this issue).
2. We are sometimes erasing the wrong expression (causing pessimism)
because our equality says loads and stores are the same.
We introduce an exact equality function and use it when erasing to
make sure we erase only identical expressions, not equivalent ones.

llvm-svn: 304807
2017-06-06 17:15:28 +00:00
Joey Gouly 61eaa63b65 [InstSimplify] Constant fold the new GEP in SimplifyGEPInst.
llvm-svn: 304784
2017-06-06 10:17:14 +00:00
Daniel Berlin be3e7ba45e NewGVN: Fix PR 33185 by checking whether we need to recursively
generate a phi of ops, which we don't currently support.

llvm-svn: 304272
2017-05-31 01:47:32 +00:00
Daniel Berlin 9ceafe267b Fix test that wasn't update_test_check'd
llvm-svn: 304271
2017-05-31 01:47:29 +00:00
Daniel Berlin e67c322260 NewGVN: Fix PR 33119, PR 33129, due to regressed undef handling
Fix PR33120 and others by eliminating self-cycles a different way.

llvm-svn: 303875
2017-05-25 15:44:20 +00:00
Davide Italiano fd9100e056 [NewGVN] Update additionalUsers when we simplify to a value.
Otherwise we don't revisit an instruction that could be simplified,
and when we verify, we discover there's something that changed, i.e.
what we had wasn't a maximal fixpoint.

Fixes PR32836.

llvm-svn: 303715
2017-05-24 02:30:24 +00:00
Daniel Berlin d130b6c27d NewGVN: Fix PR 33116, the memoryphi version of bug 32838.
llvm-svn: 303521
2017-05-21 23:41:58 +00:00
Davide Italiano 3318970cd3 [NewGVN] Actually check the NewGVN output.
Apparently I messed up squashing two consecutive commits.

llvm-svn: 303516
2017-05-21 20:55:53 +00:00
Davide Italiano f3540cff9d [NewGVN] Add a test for non most dominating leader.
Taken from PR32845. Dan removed the most dominating leader check
in r303443, but we check this test anyway to make sure things
don't regress.

llvm-svn: 303515
2017-05-21 20:50:16 +00:00
Davide Italiano 9a0f542db6 [NewGVN] Create a StoreExpression instead of a VariableExpression.
In the case where we have an operand defined by a lod of the
same memory location. Historically this was a VariableExpression
because we wanted to make sure they ended up in the same class,
but if we create the right expression, they end up in the same
class anyway.

Fixes PR32897. Thanks to Dan for the detailed discussion and the
fix suggestion.

llvm-svn: 303475
2017-05-20 00:46:54 +00:00
Daniel Berlin e021d2d629 NewGVN: Fix PR32838.
This is a complicated bug involving two issues:
1. What do we do with phi nodes when we prove all arguments are not
live?
2. When is it safe to use value leaders to determine if we can ignore
an argumnet?

llvm-svn: 303453
2017-05-19 20:22:20 +00:00
Daniel Berlin b527b2cf13 Last of the major pieces to NewGVN - yay!
Summary:
NewGVN: Handle equivalence between phi of ops and op of phis.

This makes our GVN mostly-complete. It would be complete, modulo some
deliberate choices we make.  This means it detects roughly all herband
equivalences in polynomial time, including cases notoriously hard for
other GVN's to detect.  It also detects a very large swath of the
cases we currently rely on instcombine to detect that involve folding
upwards through phis.

Fixes PR 31125, 31463, PR 31868

Reviewers: davide

Subscribers: Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D32151

llvm-svn: 303444
2017-05-19 19:01:27 +00:00
Davide Italiano ee49f4943c [NewGVN] Delete the old store when we find congruent to a load.
(or non-store, more in general). Fixes PR33086. Caught by the
store verifier.

llvm-svn: 303406
2017-05-19 04:06:10 +00:00
Davide Italiano eab0de2b82 [NewGVN] Break infinite recursion in singleReachablePHIPath().
We can have cycles between PHIs and this causes singleReachablePhi()
to call itself indefintely (until we run out of stack). The proper
solution would be that of computing SCCs, but it's not worth for
now, so just keep a visited set and give up when we find a cycle.
Thanks to Dan for the discussion/help with this.

Fixes PR33014.

llvm-svn: 303393
2017-05-18 23:22:44 +00:00
Davide Italiano a76e5fa111 [NewGVN] Replace predicate info leftovers.
This time with an additional fix, i.e. we remove the dead
@llvm.ssa.copy instruction.

llvm-svn: 303385
2017-05-18 21:43:23 +00:00
Davide Italiano 65699e5e7d [NewGVN] Re-enable test now that the nondeterminism has been fixed.
llvm-svn: 303217
2017-05-16 22:27:06 +00:00
Davide Italiano a641842845 Revert "[NewGVN] Replace predicate info leftovers."
It's breaking the bots.

llvm-svn: 303142
2017-05-16 05:51:21 +00:00
Davide Italiano 331058fcc4 [NewGVN] Replace predicate info leftovers.
Fixes PR32945.

Differential Revision:  https://reviews.llvm.org/D33226

llvm-svn: 303141
2017-05-16 05:23:23 +00:00