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104048 Commits

Author SHA1 Message Date
Hiroshi Inoue
4ea2be813b fix trivial typos, NFC
succesor -> successor

llvm-svn: 306393
2017-06-27 10:35:37 +00:00
Diana Picus
ea6a9bf804 [ARM] GlobalISel: Support G_SELECT for pointers
All we need to do is mark it as legal, otherwise it's just like s32.

llvm-svn: 306390
2017-06-27 10:29:50 +00:00
Daniel Sanders
5a18d6f64e [globalisel][tablegen] Add support for EXTRACT_SUBREG.
Summary:
After this patch, we finally have test cases that require multiple
instruction emission.

Depends on D33590

Reviewers: ab, qcolombet, t.p.northover, rovka, kristof.beyls

Subscribers: javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D33596

llvm-svn: 306388
2017-06-27 10:11:39 +00:00
Simon Dardis
6e21f583f7 [mips] Refine the condition for when to use CALL16 vs a GOT displacement.
Borrow from the logic for 'jal' in MipsAsmParser::processInstruction
and add the extra condition of bypassing CALL16 if the destination symbol
is an ELF symbol with STB_LOCAL binding.

Patch by: John Baldwin

Reviewers: sdardis

Differential Revision: https://reviews.llvm.org/D33999

llvm-svn: 306387
2017-06-27 10:11:11 +00:00
Diana Picus
0ccc7d292d [ARM] GlobalISel: Support G_SELECT for i32
* Mark as legal for (s32, i1, s32, s32)
* Map everything into GPRs
* Select to two instructions: a CMP of the condition against 0, to set
  the flags, and a MOVCCr to select between the two inputs based on the
  flags that we've just set

llvm-svn: 306382
2017-06-27 09:19:51 +00:00
Ayal Zaks
af4e296f51 Recommitting 306331.
Undoing revert 306338 after fixed bug: add metadata to the load instead of the
reverse shuffle added to it, retaining the original ValueMap implementation.

llvm-svn: 306381
2017-06-27 08:41:19 +00:00
Chandler Carruth
5fe29694c7 [SROA] Fix PR32902 by more carefully propagating !nonnull metadata.
This is based heavily on the work done ni D34285. I mostly wanted to do
test cleanup for the author to save them some time, but I had a really
hard time understanding why it was so hard to write better test cases
for these issues.

The problem is that because SROA does a second rewrite of the loads and
because we *don't* propagate !nonnull for non-pointer loads, we first
introduced invalid !nonnull metadata and then stripped it back off just
in time to avoid most ways of this PR manifesting. Moving to the more
careful utility only fixes this by changing the predicate to look at the
new load's type rather than the target type. However, that *does* fix
the bug, and the utility is much nicer including adding range metadata
to model the nonnull property after a conversion to an integer.

However, we have bigger problems because we don't actually propagate
*range* metadata, and the utility to do this extracted from instcombine
isn't really in good shape to do this currently. It *only* handles the
case of copying range metadata from an integer load to a pointer load.
It doesn't even handle the trivial cases of propagating from one integer
load to another when they are the same width! This utility will need to
be beefed up prior to using in this location to get the metadata to
fully survive.

And even then, we need to go and teach things to turn the range metadata
into an assume the way we do with nonnull so that when we *promote* an
integer we don't lose the information.

All of this will require a new test case that looks kind-of like
`preserve-nonnull.ll` does here but focuses on range metadata. It will
also likely require more testing because it needs to correctly handle
changes to the integer width, especially as SROA actively tries to
change the integer width!

Last but not least, I'm a little worried about hooking the range
metadata up here because the instcombine logic for converting from
a range metadata *to* a nonnull metadata node seems broken in the face
of non-zero address spaces where null is not mapped to the integer `0`.
So that probably needs to get fixed with test cases both in SROA and in
instcombine to cover it.

But this *does* extract the core PR fix from D34285 of preventing the
!nonnull metadata from being propagated in a broken state just long
enough to feed into promotion and crash value tracking.

On D34285 there is some discussion of zero-extend handling because it
isn't necessary. First, the new load size covers all of the non-undef
(ie, possibly initialized) bits. This may even extend past the original
alloca if loading those bits could produce valid data. The only way its
valid for us to zero-extend an integer load in SROA is if the original
code had a zero extend or those bits were undef. And we get to assume
things like undef *never* satifies nonnull, so non undef bits can
participate here. No need to special case the zero-extend handling, it
just falls out correctly.

The original credit goes to Ariel Ben-Yehuda! I'm mostly landing this to
save a few rounds of trivial edits fixing style issues and test case
formulation.

Differental Revision: D34285

llvm-svn: 306379
2017-06-27 08:32:03 +00:00
Nicolai Haehnle
5cfc836f21 AMDGPU: M0 operands to spill/restore opcodes are dead
Summary:
With scalar stores, M0 is clobbered and therefore marked as implicitly
defined. However, it is also dead.

This fixes an assertion when the Greedy Register Allocator decides to
optimize a spill/restore pair away again (via tryHintsRecoloring).

Reviewers: arsenm

Subscribers: qcolombet, kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D33319

llvm-svn: 306375
2017-06-27 08:04:13 +00:00
Galina Kistanova
b90b6a7f50 Fixed the warning introduced by r306289 to make ubuntu-gcc7.1-werror bot green.
llvm-svn: 306369
2017-06-27 06:58:57 +00:00
Mikael Holmen
77abaecf43 [Reassociate] Make sure EraseInst sets MadeChange
Summary:
EraseInst didn't report that it made IR changes through MadeChange.

It is essential that changes to the IR are reported correctly,
since for example ReassociatePass::run() will indicate that all
analyses are preserved otherwise.
And the CGPassManager determines if the CallGraph is up-to-date
based on status from InstructionCombiningPass::runOnFunction().

Reviewers: craig.topper, rnk, davide

Reviewed By: rnk, davide

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34616

llvm-svn: 306368
2017-06-27 05:32:13 +00:00
Hiroshi Inoue
69391ac868 [PowerPC] set optimization level in SelectionDAGISel
PowerPC backend does not pass the current optimization level to SelectionDAGISel and so SelectionDAGISel works with the default optimization level regardless of the current optimization level.
This patch makes the PowerPC backend set the optimization level correctly.

Differential Revision: https://reviews.llvm.org/D34615

llvm-svn: 306367
2017-06-27 04:52:17 +00:00
Leslie Zhai
a7df05b4cf [AVR] Migrate to new MCAsmBackend applyFixup and processFixupValue
Reviewers: rafael, dylanmckay, jroelofs, meadori

Reviewed By: rafael, meadori

Subscribers: meadori, llvm-commits

Differential Revision: https://reviews.llvm.org/D34551

llvm-svn: 306359
2017-06-27 03:29:27 +00:00
Davide Italiano
d5e4c1ecf6 [CFLAA] Move a common function to the header to reduce duplication.
Differential Revision:  https://reviews.llvm.org/D34660

llvm-svn: 306354
2017-06-27 02:25:06 +00:00
Matthias Braun
c9980d490b ScheduleDAGInstrs: Fix fixupKills() adding too many kill flags.
Remove invalid shortcut in fixupKills(): A register needs to be marked
live even when we are not adding a kill flag. This is because a
partially live register must not get a kill flags, but it still needs to
be fully marked live when walking backwards.

llvm-svn: 306352
2017-06-27 00:58:48 +00:00
Davide Italiano
9d27a717e2 [CFLAA] Use raw pointers instead of Optional<Pointer>. NFC.
Using Optional<> here doesn't seem to be terribly valuable, but
this is not the main point of this change. The change enables
us to merge the (now) two identical copies of parentFunctionOfValue()
that Steensgaard's and Andersens' provide.

llvm-svn: 306351
2017-06-27 00:33:37 +00:00
Davide Italiano
d85eb15c27 [CFLAA] Change FunctionHandle to be common to Steensgaard's and Andersens'
Differential Revision:  https://reviews.llvm.org/D34638

llvm-svn: 306348
2017-06-26 23:59:14 +00:00
Wolfgang Pieb
038c037dfc DAGCombine: Make sure we only eliminate trunc/extend when the scales of truncation and extension match.
This fixes PR33368.

Reviewer: rksimon

Differential Revision:  https://reviews.llvm.org/D34069

llvm-svn: 306345
2017-06-26 23:05:51 +00:00
Dehao Chen
57e415b733 revert r306336 for breaking ppc test.
llvm-svn: 306344
2017-06-26 23:05:35 +00:00
Eugene Zelenko
0e7a6818a7 [CodeGen] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 306341
2017-06-26 22:44:03 +00:00
Vedant Kumar
8d4df3cb7d [Coverage] Improve readability by using a struct. NFC.
llvm-svn: 306340
2017-06-26 22:33:06 +00:00
Ayal Zaks
45e68f8b0a reverting 306331.
Causes TBAA metadata to be generates on reverse shuffles, investigating.

llvm-svn: 306338
2017-06-26 22:26:54 +00:00
Dehao Chen
f2ec2d4e8b Enable vectorizer-maximize-bandwidth by default.
Summary:
vectorizer-maximize-bandwidth is generally useful in terms of performance. I've tested the impact of changing this to default on speccpu benchmarks on sandybridge machines. The result shows non-negative impact:

spec/2006/fp/C++/444.namd                 26.84  -0.31%
spec/2006/fp/C++/447.dealII               46.19  +0.89%
spec/2006/fp/C++/450.soplex               42.92  -0.44%
spec/2006/fp/C++/453.povray               38.57  -2.25%
spec/2006/fp/C/433.milc                   24.54  -0.76%
spec/2006/fp/C/470.lbm                    41.08  +0.26%
spec/2006/fp/C/482.sphinx3                47.58  -0.99%
spec/2006/int/C++/471.omnetpp             22.06  +1.87%
spec/2006/int/C++/473.astar               22.65  -0.12%
spec/2006/int/C++/483.xalancbmk           33.69  +4.97%
spec/2006/int/C/400.perlbench             33.43  +1.70%
spec/2006/int/C/401.bzip2                 23.02  -0.19%
spec/2006/int/C/403.gcc                   32.57  -0.43%
spec/2006/int/C/429.mcf                   40.35  +0.27%
spec/2006/int/C/445.gobmk                 26.96  +0.06%
spec/2006/int/C/456.hmmer                  24.4  +0.19%
spec/2006/int/C/458.sjeng                 27.91  -0.08%
spec/2006/int/C/462.libquantum            57.47  -0.20%
spec/2006/int/C/464.h264ref               46.52  +1.35%

geometric mean                                   +0.29%

The regression on 453.povray seems real, but is due to secondary effects as all hot functions are bit-identical with and without the flag.

I started this patch to consult upstream opinions on this. It will be greatly appreciated if the community can help test the performance impact of this change on other architectures so that we can decided if this should be target-dependent.

Reviewers: hfinkel, mkuper, davidxl, chandlerc

Reviewed By: chandlerc

Subscribers: rengolin, sanjoy, javed.absar, bjope, dorit, magabari, RKSimon, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D33341

llvm-svn: 306336
2017-06-26 21:41:09 +00:00
Dehao Chen
1003b2bc34 Fix the bug when handling shufflevector for aarch64.
Summary: This Fixes https://bugs.llvm.org/show_bug.cgi?id=33600

Reviewers: mssimpso, davidxl, Carrot

Reviewed By: mssimpso

Subscribers: aemerson, rengolin, sanjoy, javed.absar, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D34641

llvm-svn: 306334
2017-06-26 21:33:51 +00:00
Matt Arsenault
76ea38a523 RenameIndependentSubregs: Fix iterator problem
Fixes bug 33597.

Use of substituteRegister in the tied operand case messes
up the register use iterator, causing some uses to be left
unprocessed.

llvm-svn: 306333
2017-06-26 21:33:36 +00:00
Ayal Zaks
b5aa1c975d [LV] Changing the interface of ValueMap, NFC.
Instead of providing access to the internal MapStorage holding all Values
associated with a given Key, used for setting or resetting them all together,
ValueMap keeps its MapStorage internal; its new interface allows getting,
setting or resetting a single Value, per part or per part-and-lane.
Follows the discussion in https://reviews.llvm.org/D32871.

Differential Revision: https://reviews.llvm.org/D34473

llvm-svn: 306331
2017-06-26 21:03:51 +00:00
Tim Northover
cd830aa42d AArch64: legalize G_EXTRACT operations.
This is the dual problem to legalizing G_INSERTs so most of the code and
testing was cribbed from there.

llvm-svn: 306328
2017-06-26 20:34:13 +00:00
Paul Robinson
e6a67cc681 [DWARF] NFC: Give DwarfFormat a 1-byte base type.
In particular this reduces DWARFFormParams from 64 to 32 bits; pass it
around by value.

llvm-svn: 306324
2017-06-26 19:52:32 +00:00
Tim Northover
9f111d1ec1 AArch64: remove all kill flags when extending register liveness.
When we forward a stored value to a load and eliminate it entirely we need to
make sure the liveness of the register is maintained all the way to its use.
Previously we only cleared liveness on the store doing the forwarding, but
there could be other killing uses in between.

We already do the right thing when the load has to be converted into something
else, it was just this one path that skipped it.

llvm-svn: 306318
2017-06-26 18:49:25 +00:00
Paul Robinson
2cafddfdc8 [DWARF] NFC: Collect info used by DWARFFormValue into a helper.
Some forms have sizes that depend on the DWARF version, DWARF format
(32/64-bit), or the size of an address.  Collect these into a struct
to simplify passing them around.  Require callers to provide one when
they query a form's size.

Differential Revision: http://reviews.llvm.org/D34570

llvm-svn: 306315
2017-06-26 18:43:01 +00:00
Wei Mi
402b9f7bb9 [GVN] Recommit the patch "Add phi-translate support in scalarpre".
The recommit fixes three bugs: The first one is to use CurrentBlock instead of
PREInstr's Parent as param of performScalarPREInsertion because the Parent
of a clone instruction may be uninitialized. The second one is stop PRE when
CurrentBlock to its predecessor is a backedge and an operand of CurInst is
defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available. The third one is an out-of-bound
array access in a flipped if guard.

Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.

long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();

void foo(long a, long b, long c, long d) {

  g1 = a * b;
  if (__builtin_expect(g2 > 3, 0)) {
    a = c;
    b = d;
    g2 = a * b;
  }
  g3 = a * b;      // fully redundant.

}

The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.

llvm-svn: 306313
2017-06-26 18:16:10 +00:00
Matt Arsenault
ddc8acca87 AMDGPU: Setup SP/FP in callee function prolog/epilog
llvm-svn: 306312
2017-06-26 17:53:59 +00:00
Eric Beckmann
ba75b2c464 Replace trivial use of external rc.exe by writing our own .res file.
This patch removes the dependency on the external rc.exe tool by writing
a simple .res file using our own library. In this patch I also added an
explicit definition for the .res file magic.  Furthermore, I added a
unittest for embeded manifests and fixed a bug exposed by the test.

llvm-svn: 306311
2017-06-26 17:43:30 +00:00
Ulrich Weigand
8dc10b2d40 [SystemZ] Fix missing emergency spill slot corner case
We sometimes need emergency spill slots for the register scavenger.
This may be the case when code needs to access a stack slot that
has an offset of 4096 or more relative to the stack pointer.

To make that determination, processFunctionBeforeFrameFinalized
currently simply checks the total stack frame size of the current
function.  But this is not enough, since code may need to access
stack slots in the caller's stack frame as well, in particular
incoming arguments stored on the stack.

This commit fixes the problem by taking argument slots into account.

llvm-svn: 306305
2017-06-26 16:50:32 +00:00
Marina Yatsina
27c6e194b0 [inline asm] dot operator while using imm generates wrong ir + asm - llvm part
Inline asm dot operator while using imm generates wrong ir and asm

This also fixes bugzilla 32987:
https://bugs.llvm.org//show_bug.cgi?id=32987

The clang part of the review that contains the test can be found here:
https://reviews.llvm.org/D33040

commit on behald of zizhar

Differential Revision:
https://reviews.llvm.org/D33039

llvm-svn: 306300
2017-06-26 16:03:42 +00:00
Ahmed Bougacha
888a374555 [X86][AVX-512] Don't raise inexact in ceil, floor, round, trunc.
The non-AVX-512 behavior was changed in r248266 to match N1778
(C bindings for IEEE-754 (2008)), which defined the four functions
to not raise the inexact exception ("rint" is still defined as raising
it).

Update the AVX-512 lowering of these functions to match that: it should
not be different.

llvm-svn: 306299
2017-06-26 16:00:24 +00:00
Tom Stellard
4e1d2d8ecf AMDGPU/GlobalISel: Mark 32-bit G_SHL as legal
Reviewers: arsenm

Reviewed By: arsenm

Subscribers: kzhuravl, wdng, nhaehnle, yaxunl, rovka, kristof.beyls, igorb, dstuttard, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D34589

llvm-svn: 306298
2017-06-26 15:56:52 +00:00
Sanjay Patel
43a91b22c0 [x86] transform vector inc/dec to use -1 constant (PR33483)
Convert vector increment or decrement to sub/add with an all-ones constant:

add X, <1, 1...> --> sub X, <-1, -1...>
sub X, <1, 1...> --> add X, <-1, -1...>

The all-ones vector constant can be materialized using a pcmpeq instruction that is 
commonly recognized as an idiom (has no register dependency), so that's better than 
loading a splat 1 constant.

AVX512 uses 'vpternlogd' for 512-bit vectors because there is apparently no better
way to produce 512 one-bits.

The general advantages of this lowering are:
1. pcmpeq has lower latency than a memop on every uarch I looked at in Agner's tables, 
   so in theory, this could be better for perf, but...

2. That seems unlikely to affect any OOO implementation, and I can't measure any real 
   perf difference from this transform on Haswell or Jaguar, but...

3. It doesn't look like it from the diffs, but this is an overall size win because we 
   eliminate 16 - 64 constant bytes in the case of a vector load. If we're broadcasting 
   a scalar load (which might itself be a bug), then we're replacing a scalar constant 
   load + broadcast with a single cheap op, so that should always be smaller/better too.

4. This makes the DAG/isel output more consistent - we use pcmpeq already for padd x, -1 
   and psub x, -1, so we should use that form for +1 too because we can. If there's some
   reason to favor a constant load on some CPU, let's make the reverse transform for all
   of these cases (either here in the DAG or in a later machine pass).

This should fix:
https://bugs.llvm.org/show_bug.cgi?id=33483

Differential Revision: https://reviews.llvm.org/D34336

llvm-svn: 306289
2017-06-26 14:19:26 +00:00
Krzysztof Parzyszek
f30628d6b1 [Hexagon] Handle cases when the aligned stack pointer is missing
llvm-svn: 306288
2017-06-26 14:17:58 +00:00
Jonas Paulsson
12cce93ec7 [SystemZ] Add a check against zero before calling getTestUnderMaskCond()
Csmith discovered that this function can be called with a zero argument,
in which case an assert for this triggered.

This patch also adds a guard before the other call to this function since
it was missing, although the test only covers the case where it was
discovered.

Reduced test case attached as CodeGen/SystemZ/int-cmp-54.ll.

Review: Ulrich Weigand
llvm-svn: 306287
2017-06-26 13:38:27 +00:00
Mikael Holmen
b58321ae94 [IfConversion] Hoist removeBranch calls out of if/else clauses [NFC]
Summary:
Also added a comment.

Pulled out of https://reviews.llvm.org/D34099.

Reviewers: iteratee

Reviewed By: iteratee

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34388

llvm-svn: 306279
2017-06-26 09:33:04 +00:00
Craig Topper
63e0ccb0ef [IR] Rename BinaryOperator::init to AssertOK and remove argument. Replace default case in switch with llvm_unreachable since all valid opcodes are covered.
This method doesn't do any initializing. It just contains asserts. So renaming to AssertOK makes it consistent with similar instructions in other Instruction classes.

llvm-svn: 306277
2017-06-26 07:15:59 +00:00
Serguei Katkov
63a64a0d08 This reverts commit r306272.
Revert "[MBP] do not rotate loop if it creates extra branch"

It breaks the sanitizer build bots. Need to fix this.

llvm-svn: 306276
2017-06-26 06:51:45 +00:00
Serguei Katkov
0f120ff044 [MBP] do not rotate loop if it creates extra branch
This is a last fix for the corner case of PR32214. Actually this is not really corner case in general.

We should not do a loop rotation if we create an additional branch due to it.
Consider the case where we have a loop chain H, M, B, C , where
H is header with viable fallthrough from pre-header and exit from the loop
M - some middle block
B - backedge to Header but with exit from the loop also.
C - some cold block of the loop.

Let's H is determined as a best exit. If we do a loop rotation M, B, C, H we can introduce the extra branch.
Let's compute the change in number of branches:
+1 branch from pre-header to header
-1 branch from header to exit
+1 branch from header to middle block if there is such
-1 branch from cold bock to header if there is one

So if C is not a predecessor of H then we introduce extra branch.

This change actually prohibits rotation of the loop if both true
1) Best Exit has next element in chain as successor.
2) Last element in chain is not a predecessor of first element of chain.

Reviewers: iteratee, xur
Reviewed By: iteratee
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34271

llvm-svn: 306272
2017-06-26 05:27:27 +00:00
Davide Italiano
b3201ae5c9 [CFL-AA] Remove unneeded function declaration. NFCI.
llvm-svn: 306268
2017-06-26 03:55:41 +00:00
Chandler Carruth
403d788d88 [InstCombine] Factor the logic for propagating !nonnull and !range
metadata out of InstCombine and into helpers.

NFC, this just exposes the logic used by InstCombine when propagating
metadata from one load instruction to another. The plan is to use this
in SROA to address PR32902.

If anyone has better ideas about how to factor this or name variables,
I'm all ears, but this seemed like a pretty good start and lets us make
progress on the PR.

This is based on a patch by Ariel Ben-Yehuda (D34285).

llvm-svn: 306267
2017-06-26 03:31:31 +00:00
Matt Arsenault
06d9b51c75 AMDGPU: Whitespace fixes
llvm-svn: 306265
2017-06-26 03:01:36 +00:00
Matt Arsenault
9b6d8d16dd AMDGPU: Partially fix implicit.buffer.ptr intrinsic handling
This should not be treated as a different version of
private_segment_buffer. These are distinct things with
different uses and register classes, and requires the
function argument info to have more context about the
function's type and environment.

Also add missing test coverage for the intrinsic, and
emit an error for HSA. This also encovers that the intrinsic
is broken unless there happen to be stack objects.

llvm-svn: 306264
2017-06-26 03:01:31 +00:00
Chandler Carruth
72cda64d90 [LoopSimplify] Re-instate r306081 with a bug fix w.r.t. indirectbr.
This was reverted in r306252, but I already had the bug fixed and was
just trying to form a test case.

The original commit factored the logic for forming dedicated exits
inside of LoopSimplify into a helper that could be used elsewhere and
with an approach that required fewer intermediate data structures. See
that commit for full details including the change to the statistic, etc.

The code looked fine to me and my reviewers, but in fact didn't handle
indirectbr correctly -- it left the 'InLoopPredecessors' vector dirty.

If you have code that looks *just* right, you can end up leaking these
predecessors into a subsequent rewrite, and crash deep down when trying
to update PHI nodes for predecessors that don't exist.

I've added an assert that makes the bug much more obvious, and then
changed the code to reliably clear the vector so we don't get this bug
again in some other form as the code changes.

I've also added a test case that *does* manage to catch this while also
giving some nice positive coverage in the face of indirectbr.

The real code that found this came out of what I think is CPython's
interpreter loop, but any code with really "creative" interpreter loops
mixing indirectbr and other exit paths could manage to tickle the bug.
I was hard to reduce the original test case because in addition to
having a particular pattern of IR, the whole thing depends on the order
of the predecessors which is in turn depends on use list order. The test
case added here was designed so that in multiple different predecessor
orderings it should always end up going down the same path and tripping
the same bug. I hope. At least, it tripped it for me without
manipulating the use list order which is better than anything bugpoint
could do...

llvm-svn: 306257
2017-06-25 22:45:31 +00:00
Davide Italiano
917627da76 [MemDep] Cleanup return after else & use auto. NFC.
llvm-svn: 306255
2017-06-25 22:12:59 +00:00
Anna Thomas
1714e72712 [LoopDeletion] NFC: Move phi node value setting into prepass
Recommit NFC patch (rL306157) where I missed incrementing the basic block iterator,
which caused loop deletion tests to hang due to infinite loop.
Had reverted it in rL306162.

rL306157 commit message:
Currently, the implementation of delete dead loops has a special case
when the loop being deleted is never executed. This special case
(updating of exit block's incoming values for phis) can be
run as a prepass for non-executable loops before performing
the actual deletion.

llvm-svn: 306254
2017-06-25 21:13:58 +00:00