Commit Graph

20898 Commits

Author SHA1 Message Date
Max Kazantsev 8e59cd1915 [LICM] Hoist guards from non-header blocks
This patch relaxes overconservative checks on whether or not we could write
memory before we execute an instruction. This allows us to hoist guards out of
loops even if they are not in the header block.

Differential Revision: https://reviews.llvm.org/D50891
Reviewed By: fedor.sergeev



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346643 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-12 09:29:58 +00:00
Calixte Denizet b7ec431ced [GCOV] Add options to filter files which must be instrumented.
Summary:
When making code coverage, a lot of files (like the ones coming from /usr/include) are removed when post-processing gcno/gcda so finally they doen't need to be instrumented nor to appear in gcno/gcda.
The goal of the patch is to be able to filter the files we want to instrument, there are several advantages to do that:
- improve speed (no overhead due to instrumentation on files we don't care)
- reduce gcno/gcda size
- it gives the possibility to easily instrument only few files (e.g. ones modified in a patch) without changing the build system
- need to accept this patch to be enabled in clang: https://reviews.llvm.org/D52034

Reviewers: marco-c, vsk

Reviewed By: marco-c

Subscribers: llvm-commits, sylvestre.ledru

Differential Revision: https://reviews.llvm.org/D52033

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346641 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-12 09:01:43 +00:00
Florian Hahn d3caae0ce2 [IPSCCP,PM] Preserve PDT in the new pass manager.
Reviewers: kuhar, chandlerc, NutshellySima, brzycki

Reviewed By: NutshellySima, brzycki

Differential Revision: https://reviews.llvm.org/D54317



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346618 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-11 20:22:45 +00:00
Sanjay Patel 7c38906dea [InstCombine] simplify code for merging stores; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346596 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-10 20:29:25 +00:00
Eugene Leviant 10c84a8f35 [ThinLTO] Internalize readonly globals
This patch allows internalising globals if all accesses to them
(from live functions) are from non-volatile load instructions

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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346584 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-10 08:31:21 +00:00
Eli Friedman bd0f067b12 [JumpThreading] Fix exponential time algorithm computing known values.
ComputeValueKnownInPredecessors has a "visited" set to prevent infinite
loops, since a value can be visited more than once.  However, the
implementation didn't prevent the algorithm from taking exponential
time. Instead of removing elements from the RecursionSet one at a time,
we should keep around the whole set until
ComputeValueKnownInPredecessors finishes, then discard it.

The testcase is synthetic because I was having trouble effectively
reducing the original.  But it's basically the same idea.

Instead of failing, we could theoretically cache the result instead.
But I don't think it would help substantially in practice.

Differential Revision: https://reviews.llvm.org/D54239



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346562 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-09 22:35:26 +00:00
Florian Hahn d81571aae0 Revert r346483: [CallSiteSplitting] Only record conditions up to the IDom(call site).
This cause a failure with EXPENSIVE_CHECKS


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346492 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-09 13:28:58 +00:00
Florian Hahn 33b71d2257 [IPSCCP,PM] Preserve DT in the new pass manager.
After D45330, Dominators are required for IPSCCP and can be preserved.

This patch preserves DominatorTreeAnalysis in the new pass manager. AFAIK the legacy pass manager cannot preserve function analysis required by a module analysis.

Reviewers: davide, dberlin, chandlerc, efriedma, kuhar, NutshellySima

Reviewed By: chandlerc, kuhar, NutshellySima

Differential Revision: https://reviews.llvm.org/D47259


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346486 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-09 11:52:27 +00:00
Florian Hahn 04e9fcb512 [CallSiteSplitting] Only record conditions up to the IDom(call site).
We can stop recording conditions once we reached the immediate dominator
for the block containing the call site. Conditions in predecessors of the
that node will be the same for all paths to the call site and splitting
is not beneficial.

This patch makes CallSiteSplitting dependent on the DT anlysis. because
the immediate dominators seem to be the easiest way of finding the node
to stop at.

I had to update some exiting tests, because they were checking for
conditions that were true/false on all paths to the call site. Those
should now be handled by instcombine/ipsccp.

Reviewers: davide, junbuml

Reviewed By: junbuml

Differential Revision: https://reviews.llvm.org/D44627


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346483 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-09 10:23:46 +00:00
Carlos Alberto Enciso 8381d3e303 [DebugInfo][Dexter] Unreachable line stepped onto after SimplifyCFG.
In SimplifyCFG when given a conditional branch that goes to BB1 and BB2, the hoisted common terminator instruction in the two blocks, caused debug line records associated with subsequent select instructions to become ambiguous. It causes the debugger to display unreachable source lines.

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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346481 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-09 09:42:10 +00:00
Max Kazantsev 244a2cf3ab [NFC] Add utility function for SafetyInfo updates for moveBefore
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346472 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-09 05:39:04 +00:00
Florian Hahn 2cfa2297db [LoopInterchange] Support reductions across inner and outer loop.
This patch adds logic to detect reductions across the inner and outer
loop by following the incoming values of PHI nodes in the outer loop. If
the incoming values take part in a reduction in the inner loop or come
from outside the outer loop, we found a reduction spanning across inner
and outer loop.

With this change, ~10% more loops are interchanged in the LLVM
test-suite + SPEC2006.

Fixes https://bugs.llvm.org/show_bug.cgi?id=30472

Reviewers: mcrosier, efriedma, karthikthecool, davide, hfinkel, dmgreen

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D43245


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346438 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 20:44:19 +00:00
Pirama Arumuga Nainar 32530669f1 [LTO] Drop non-prevailing definitions only if linkage is not local or appending
Summary:
This fixes PR 37422

In ELF, non-weak symbols can also be non-prevailing.  In this particular
PR, the __llvm_profile_* symbols are non-prevailing but weren't getting
dropped - causing multiply-defined errors with lld.

Also add a test, strong_non_prevailing.ll, to ensure that multiple
copies of a strong symbol are dropped.

To fix the test regressions exposed by this fix,
- do not mark prevailing copies for symbols with 'appending' linkage.
There's no one prevailing copy for such symbols.
- fix the prevailing version in dead-strip-fulllto.ll
- explicitly pass exported symbols to llvm-lto in fumcimport.ll and
funcimport_var.ll

Reviewers: tejohnson, pcc

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith,
dang, srhines, llvm-commits

Differential Revision: https://reviews.llvm.org/D54125

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346436 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 20:10:07 +00:00
Tom Stellard 188cca3dd5 InstCombine: Avoid introducing poison values when lowering llvm.amdgcn.[us]bfe
Summary:
When the 3rd argument to these intrinsics is zero, lowering them
to shift instructions produces poison values, since we end up with
shift amounts equal to the number of bits in the shifted value.  This
means we can only lower these intrinsics if we can prove that the
3rd argument is not zero.

Reviewers: arsenm

Reviewed By: arsenm

Subscribers: bnieuwenhuizen, jvesely, wdng, nhaehnle, llvm-commits

Differential Revision: https://reviews.llvm.org/D53739

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346422 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 17:57:57 +00:00
Vedant Kumar da31f7b670 [CodeExtractor] Mark functions noreturn when applicable
This eliminates the outlining penalty for llvm.trap/unreachable, because
callers no longer have to emit cleanup/ret instructions after calling an
outlined `noreturn` function.

rdar://45523626

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346421 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 17:57:09 +00:00
Max Kazantsev 36c468a39f Return "[IndVars] Smart hard uses detection"
The patch has been reverted because it ended up prohibiting propagation
of a constant to exit value. For such values, we should skip all checks
related to hard uses because propagating a constant is always profitable.

Differential Revision: https://reviews.llvm.org/D53691


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346397 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 11:54:35 +00:00
Gil Rapaport 36fe44dfcc [LSR] Combine unfolded offset into invariant register
LSR reassociates constants as unfolded offsets when the constants fit as
immediate add operands, which currently prevents such constants from being
combined later with loop invariant registers.
This patch modifies GenerateCombinations() to generate a second formula which
includes the unfolded offset in the combined loop-invariant register.

This commit fixes a bug in the original patch (committed at r345114, reverted
at r345123).

Differential Revision: https://reviews.llvm.org/D51861


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346390 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 09:01:19 +00:00
whitequark 19a9621221 [MergeFuncs] Improve ordering of equal functions
Summary:
MergeFunctions currently tries to process strong functions before
weak functions, because weak functions can simply call strong
functions, while a strong/weak function cannot call a weak function
(a backing strong function is needed).

This patch additionally tries to process external functions before
local functions, because we definitely have to keep the external
function, but may be able to drop the local one (and definitely
can if it is also unnamed_addr).

Unfortunately, this exposes an existing bug in the implementation:
The FnTree and FNodesInTree structures can currently go out of
sync in the case where two weak functions are merged, because the
function in FnTree/FNodesInTree is RAUWed. This leaves it behind in
FnTree (this is intended, as it is the strong backing function which
should be used for further merges), while it is replaced in
FNodesInTree (this is not intended).

This is fixed by switching FNodesInTree from using a ValueMap to
using a DenseMap of AssertingVH.

This exposes another minor issue: Currently FNodesInTree is not
cleared after MergeFunctions finishes running. Currently, this is
potentially dangerous (e.g. if something else wants to RAUW a function
with a non-function), but at the very least it is unnecessary/inefficient.
After the change to use AssertingVH it becomes more problematic,
because there are certainly passes that remove functions.

This issue is fixed by clearing FNodesInTree at the end of the pass.

Reviewers: jfb, whitequark

Reviewed By: whitequark

Subscribers: rkruppe, llvm-commits

Differential Revision: https://reviews.llvm.org/D53271

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346386 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 03:58:01 +00:00
whitequark 17045f0418 [MergeFuncs] Call removeUsers() prior to unnamed_addr RAUW
Summary:
For unnamed_addr functions we RAUW instead of only replacing direct callers. However, functions in which replacements were performed currently are not added back to the worklist, resulting in missed merging opportunities.

Fix this by calling removeUsers() prior to RAUW.

Reviewers: jfb, whitequark

Reviewed By: whitequark

Subscribers: rkruppe, llvm-commits

Differential Revision: https://reviews.llvm.org/D53262

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346385 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 03:57:55 +00:00
Reid Kleckner 654fe49fb8 [sancov] Put .SCOV* sections into the right comdat groups on COFF
Avoids linker errors about relocations against discarded sections.

This was uncovered during the Chromium clang roll here:
https://chromium-review.googlesource.com/c/chromium/src/+/1321863#message-717516acfcf829176f6a2f50980f7a4bdd66469a

After this change, Chromium's libGLESv2 links successfully for me.

Reviewers: metzman, hans, morehouse

Differential Revision: https://reviews.llvm.org/D54232

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346381 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 00:57:33 +00:00
Rong Xu d079edbd8d [PGO] Exit early if all count values are zero
If all the edge counts for a function are zero, skip count population and
annotation, as nothing will happen. This can save some compile time.

Differential Revision: https://reviews.llvm.org/D54212


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346370 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 23:51:20 +00:00
Fedor Sergeev 3a7cf3b32f [SimpleLoopUnswitch] partial unswitch needs to be careful when replacing invariants with constants
When partial unswitch operates on multiple conditions at once, .e.g:
   if (Cond1 || Cond2 || NonInv) ...

it should infer (and replace) values for individual conditions only on one
side of unswitch and not another.

More precisely only these derivations hold true:
   (Cond1 || Cond2) == false  =>  Cond1 == Cond2 == false
   (Cond1 && Cond2) == true   =>  Cond1 == Cond2 == true

By the way we organize unswitching it means only replacing on "continue" blocks
and never on "unswitched" ones. Since trivial unswitch does not have "unswitched"
blocks it does not have this problem.

Fixes PR 39568.

Reviewers: chandlerc, asbirlea
Differential Revision: https://reviews.llvm.org/D54211

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346350 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 20:05:11 +00:00
Mandeep Singh Grang 06a55fc2f4 [LoopSink] Do not sink instructions into non-cold blocks
Summary: This fixes PR39570.

Reviewers: danielcdh, rnk, bkramer

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D54181

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346337 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 18:26:24 +00:00
Florian Hahn bdee2b6fc1 [NewGVN] Make sure we do not add a user to itself.
If we simplify an instruction to itself, we do not need to add a user to
itself. For congruence classes with a defining expression, we already
use a similar logic.

Fixes PR38259.

Reviewers: davide, efriedma, mcrosier

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D51168


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346335 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 17:20:07 +00:00
Sanjay Patel 7a2b35fa20 [InstCombine] propagate FMF for fcmp+fabs folds
By morphing the instruction rather than deleting and creating a new one,
we retain fast-math-flags and potentially other metadata (profile info?).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346331 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 16:15:01 +00:00
Sanjay Patel 3bfaa4d7be [InstCombine] peek through fabs() when checking isnan()
That should be the end of the missing cases for this fold.
See earlier patches in this series:
rL346321
rL346324


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346327 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 15:44:26 +00:00
Sanjay Patel b3939a8dff [InstCombine] add folds for fcmp Pred fabs(X), 0.0
Similar to rL346321, we had folds for the ordered
versions of these compares already, so add the
unordered siblings for completeness.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346324 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 15:33:03 +00:00
James Y Knight 3125e35140 Add support for llvm.is.constant intrinsic (PR4898)
This adds the llvm-side support for post-inlining evaluation of the
__builtin_constant_p GCC intrinsic.

Also fixed SCCPSolver::visitCallSite to not blow up when seeing a call
to a function where canConstantFoldTo returns true, and one of the
arguments is a struct.

Updated from patch initially by Janusz Sobczak.

Differential Revision: https://reviews.llvm.org/D4276

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346322 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 15:24:12 +00:00
Sanjay Patel b9f324c261 [InstCombine] add fold for fabs(X) u< 0.0
The sibling fold for 'oge' --> 'ord' was already here,
but this half was missing. 

The result of fabs() must be positive or nan, so asking 
if the result is negative or nan is the same as asking 
if the result is nan.

This is another step towards fixing:
https://bugs.llvm.org/show_bug.cgi?id=39475


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346321 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 15:11:32 +00:00
Sanjay Patel e9e41a0702 fix typos aggressively; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346316 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 14:35:36 +00:00
Sanjay Patel 238b8867a8 [InstCombine] do not shrink switch conditions to illegal types (PR29009)
This patch makes shrinking switch conditions less aggressive which was introduced by:
rL274233

Note that we have 2 new bugs to track potential follow-ups that might have solved PR29009
in different ways:
https://bugs.llvm.org/show_bug.cgi?id=39569
https://bugs.llvm.org/show_bug.cgi?id=39578

Patch by:
@dendibakh (Denis Bakhvalov)

Differential Revision: https://reviews.llvm.org/D54115


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346315 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 14:12:41 +00:00
Calixte Denizet bb74632144 [GCOV] Flush counters before to avoid counting the execution before fork twice and for exec** functions we must flush before the call
Summary:
This is replacement for patch in https://reviews.llvm.org/D49460.
When we fork, the counters are duplicate as they're and so the values are finally wrong when writing gcda for parent and child.
So just before to fork, we flush the counters and so the parent and the child have new counters set to zero.
For exec** functions, we need to flush before the call to have some data.

Reviewers: vsk, davidxl, marco-c

Reviewed By: marco-c

Subscribers: llvm-commits, sylvestre.ledru, marco-c

Differential Revision: https://reviews.llvm.org/D53593

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346313 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 13:49:17 +00:00
Sanjay Patel be9ce13f15 [IR] add optional parameter for copying IR flags to compare instructions
As shown, this is used to eliminate redundant code in InstCombine,
and there are more cases where we should be using this pattern, but
we're currently unintentionally dropping flags. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346282 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-07 00:00:42 +00:00
Teresa Johnson 645cd31982 [ThinLTO] Split NotEligibleToImport into legality and inlinability flags
Summary:
The NotEligibleToImport flag on the GlobalValueSummary was set if it
isn't legal to import (e.g. because it references unpromotable locals)
and when it can't be inlined (in which case importing is pointless).

I split out the inlinable piece into a separate flag on the
FunctionSummary (doesn't make sense for aliases or global variables),
because in the future we may want to import for reasons other than
inlining.

Reviewers: davidxl

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

Differential Revision: https://reviews.llvm.org/D53345

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346261 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 19:41:35 +00:00
Vedant Kumar 2b75576214 [CodeExtractor] Do not extract calls to eh_typeid_for (PR39545)
The lowering for a call to eh_typeid_for changes when it's moved from
one function to another.

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346256 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 19:06:08 +00:00
Vedant Kumar b109c4206a [CodeExtractor] Erase use-without-def debug intrinsics in parent func
When CodeExtractor moves instructions to a new function, debug
intrinsics referring to those instructions within the parent function
become invalid.

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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346255 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 19:05:53 +00:00
Sanjay Patel 09d77c0de9 [InstCombine] allow vector types for fcmp+fpext fold
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346245 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 17:20:20 +00:00
Sanjay Patel 031587fccf [InstCombine] propagate fast-math-flags when folding fcmp+fpext, part 2
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346242 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 16:45:27 +00:00
Sanjay Patel ac037d267f [InstCombine] rearrange code for fcmp+fpext; NFCI
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346241 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 16:37:35 +00:00
Sanjay Patel 6052aa3705 [InstCombine] propagate fast-math-flags when folding fcmp+fpext
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346240 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 16:23:03 +00:00
Sanjay Patel d174746db8 [InstCombine] propagate fast-math-flags when folding fcmp+fneg, part 2
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346238 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 15:58:57 +00:00
Sanjay Patel c52594aa97 [InstCombine] reduce code; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346235 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 15:53:58 +00:00
Sanjay Patel bd1a44f2b8 [InstCombine] propagate fast-math-flags when folding fcmp+fneg
This is another part of solving PR39475:
https://bugs.llvm.org/show_bug.cgi?id=39475

This might be enough to fix that particular issue, but as noted
with the FIXME, we're still dropping FMF on other folds around here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346234 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 15:49:45 +00:00
Simon Pilgrim 241a3bcfa8 [InstCombine] Ensure nested shifts are in range (OSS-Fuzz #9880)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346225 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 11:28:22 +00:00
Max Kazantsev bd5ea2b6c2 [LICM] Remove too conservative IsMustExecute variable
LICM relies on variable `MustExecute` which is conservatively set to `false`
in all non-headers. It is used when we decide whether or not we want to hoist
an instruction or a guard.

For the guards, it might be too conservative to use this variable, we can
instead use a more precise logic from LoopSafetyInfo. Currently it is only NFC
because `IsMemoryNotModified` is also conservatively set to `false` for all
non-headers, and we cannot hoist guards from non-header blocks. However once we
give up using `IsMemoryNotModified` and use a smarter check instead, this will
allow us to hoist guards from all mustexecute non-header blocks.

Differential Revision: https://reviews.llvm.org/D50888
Reveiwed By: fedor.sergeev


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346204 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 04:17:40 +00:00
Max Kazantsev 5927508e1d [LICM] Use ICFLoopSafetyInfo in LICM
This patch makes LICM use `ICFLoopSafetyInfo` that is a smarter version
of LoopSafetyInfo that leverages power of Implicit Control Flow Tracking
to keep track of throwing instructions and give less pessimistic answers
to queries related to throws.

The ICFLoopSafetyInfo itself has been introduced in rL344601. This patch
enables it in LICM only.

Differential Revision: https://reviews.llvm.org/D50377
Reviewed By: apilipenko


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346201 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 02:44:49 +00:00
Max Kazantsev a61bdda557 Revert "[IndVars] Smart hard uses detection"
This reverts commit 2f425e9c79.

It seems that the check that we still should do the transform if we
know the result is constant is missing in this code. So the logic that
has been deleted by this change is still sometimes accidentally useful.
I revert the change to see what can be done about it. The motivating
case is the following:

@Y = global [400 x i16] zeroinitializer, align 1

define i16 @foo() {
entry:
  br label %for.body

for.body:                                         ; preds = %entry, %for.body
  %i = phi i16 [ 0, %entry ], [ %inc, %for.body ]

  %arrayidx = getelementptr inbounds [400 x i16], [400 x i16]* @Y, i16 0, i16 %i
  store i16 0, i16* %arrayidx, align 1
  %inc = add nuw nsw i16 %i, 1
  %cmp = icmp ult i16 %inc, 400
  br i1 %cmp, label %for.body, label %for.end

for.end:                                          ; preds = %for.body
  %inc.lcssa = phi i16 [ %inc, %for.body ]
  ret i16 %inc.lcssa
}

We should be able to figure out that the result is constant, but the patch
breaks it.

Differential Revision: https://reviews.llvm.org/D51584


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346198 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 02:02:05 +00:00
Sanjay Patel e357c8b879 [InstSimplify] fold select (fcmp X, Y), X, Y
This is NFCI for InstCombine because it calls InstSimplify, 
so I left the tests for this transform there. As noted in
the code comment, we can allow this fold more often by using
FMF and/or value tracking.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346169 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-05 21:51:39 +00:00
Taewook Oh 960c599319 [MergeICmps] Do not perform the transformation if GEP is used outside of block
Summary:
This patch prevents MergeICmps to performn the transformation if the address operand GEP of the load instruction has a use outside of the load's parent block. Without this patch, compiler crashes with the given test case because the use of `%first.i` is still around when the basic block is erased from https://github.com/llvm-mirror/llvm/blob/master/lib/Transforms/Scalar/MergeICmps.cpp#L620. I think checking `isUsedOutsideOfBlock` with `GEP` is the original intention of the code, as the checking for `LoadI` is already performed in the same function.

This patch is incomplete though, as this makes the pass overly conservative and fails the test `tuple-four-int8.ll`. I believe what needs to be done is checking if GEP has a use outside of block that is not the part of "Comparisons" chain. Submit the patch as of now to prevent compiler crash.

Reviewers: courbet, trentxintong

Reviewed By: courbet

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D54089

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346151 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-05 18:16:32 +00:00
Sanjay Patel ab049d88fa [InstCombine] canonicalize -0.0 to +0.0 in fcmp
As stated in IEEE-754 and discussed in:
https://bugs.llvm.org/show_bug.cgi?id=38086
...the sign of zero does not affect any FP compare predicate.

Known regressions were fixed with:
rL346097 (D54001)
rL346143

The transform will help reduce pattern-matching complexity to solve:
https://bugs.llvm.org/show_bug.cgi?id=39475
...as well as improve CSE and codegen (a zero constant is almost always
easier to produce than 0x80..00).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346147 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-05 17:26:42 +00:00