Commit Graph

4881 Commits

Author SHA1 Message Date
David Stenberg 3889ff82bf [DebugInfo] Refactor DIExpression [SZ]Ext creation into function [NFC]
Summary:
Also, replace the SmallVector with a normal C array.

Reviewers: vsk

Reviewed By: vsk

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70498
2019-11-21 10:44:04 +01:00
Alina Sbirlea da4baa2a6c [MemorySSA] Update analysis when the terminator is a memory instruction.
Update MemorySSA when moving the terminator instruction, as that may be a memory touching instruction.
Resolves PR44029.
2019-11-20 16:36:52 -08:00
Philip Reames 8ba56f322a Move widenable branch formation into makeGuardControlFlowExplicit helper
This is mostly NFC, but I removed the setting of the guard's calling convention onto the WC call.  Why?  Because it was untested, and was producing an ill defined output as the declaration's convention wasn't been changed leaving a mismatch which is UB.
2019-11-20 12:54:05 -08:00
Philip Reames 70c68a6b0e [NFC] Factor out utilities for manipulating widenable branches
With the widenable condition construct, we have the ability to reason about branches which can be 'widened' (i.e. made to fail more often).  We've got a couple o transforms which leverage this.  This patch just cleans up the API a bit.

This is prep work for generalizing our definition of a widenable branch slightly.  At the moment "br i1 (and A, wc()), ..." is considered widenable, but oddly, neither "br i1 (and wc(), B), ..." or "br i1 wc(), ..." is.  That clearly needs addressed, so first, let's centralize the code in one place.
2019-11-19 14:43:13 -08:00
Teresa Johnson cc1b0bc24d [ThinLTO] Avoid extra index lookup during promotion
Summary:
Pass down the already accessed ValueInfo to shouldPromoteLocalToGlobal,
to avoid an unnecessary extra index lookup.

Add some assertion checking to confirm we have a non-empty VI when
expected.

Also some misc cleanup, merging the two versions of
doImportAsDefinition, since one was only called by the other, and
unnecessarily passed in a member variable.

Reviewers: steven_wu, pcc, evgeny777

Reviewed By: evgeny777

Subscribers: mehdi_amini, inglorion, hiraditya, dexonsmith, arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70337
2019-11-18 12:55:53 -08:00
Teresa Johnson 3be6dbca3b [ThinLTO] Promotion handling cleanup (NFC)
Summary:
Clean up the code that does GV promotion in the ThinLTO backends.

Specifically, we don't need to check whether we are importing since that
is already checked and handled correctly in shouldPromoteLocalToGlobal.
Simply call shouldPromoteLocalToGlobal, and if it returns true we are
guaranteed that we are promoting, whether or not we are importing (or in
the exporting module). This also makes the handling in getName()
consistent with that in getLinkage(), which checks the DoPromote parameter
regardless of whether we are importing or exporting.

Reviewers: steven_wu, pcc, evgeny777

Subscribers: mehdi_amini, inglorion, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70327
2019-11-18 11:59:36 -08:00
Sanjay Patel ebf9bf2cbc [SimplifyCFG] propagate fast-math-flags (FMF) from phi to select
Similar to/extension of D70208 (rGee0882bdf866), but this one
may finally allow closing motivating bugs.

This is another step towards having FMF apply only to FP values
rather than those + fcmp. See PR38086 for one of the original
discussions/motivations:
https://bugs.llvm.org/show_bug.cgi?id=38086

And the test here is derived from PR39535:
https://bugs.llvm.org/show_bug.cgi?id=39535

Currently, we lose FMF when converting any phi to select in
SimplifyCFG. There are a small number of similar changes needed
to correct within SimplifyCFG, so it should be quick to patch
this pass up.

FMF was extended to select and phi with:
D61917
D67564
2019-11-17 11:23:44 -05:00
Sanjay Patel ee0882bdf8 [SimplifyCFG] propagate fast-math-flags (FMF) from phi to select
This is another step towards having FMF apply only to FP values
rather than those + fcmp. See PR38086 for one of the original
discussions/motivations:
https://bugs.llvm.org/show_bug.cgi?id=38086

And the test here is derived from PR39535:
https://bugs.llvm.org/show_bug.cgi?id=39535

Currently, we lose FMF when converting any phi to select in
SimplifyCFG. There are a small number of similar changes needed
to correct within SimplifyCFG, so it should be quick to patch
this pass up.

FMF was extended to select and phi with:
D61917
D67564

Differential Revision: https://reviews.llvm.org/D70208
2019-11-15 16:14:35 -05:00
Francesco Petrogalli d6de5f12d4 [SVFS] Inject TLI Mappings in VFABI attribute.
This patch introduces a function pass to inject the scalar-to-vector
mappings stored in the TargetLIbraryInfo (TLI) into the Vector
Function ABI (VFABI) variants attribute.

The test is testing the injection for three vector libraries supported
by the TLI (Accelerate, SVML, MASSV).

The pass does not change any of the analysis associated to the
function.

Differential Revision: https://reviews.llvm.org/D70107
2019-11-15 18:42:56 +00:00
evgeny 3d708bf5c2 Recommit "[ThinLTO] Add correctness check for RO/WO variable import"
ValueInfo has user-defined 'operator bool' which allows incorrect implicit conversion
to GlobalValue::GUID (which is unsigned long). This causes bugs which are hard to
track and should be removed in future.
2019-11-15 16:13:19 +03:00
Reid Kleckner 4c1a1d3cf9 Add missing includes needed to prune LLVMContext.h include, NFC
These are a pre-requisite to removing #include "llvm/Support/Options.h"
from LLVMContext.h: https://reviews.llvm.org/D70280
2019-11-14 15:23:15 -08:00
Benjamin Kramer 360f661733 Revert "[ThinLTO] Add correctness check for RO/WO variable import"
This reverts commit a2292cc537. Breaks
clang selfhost w/ThinLTO.
2019-11-14 16:07:13 +01:00
evgeny a2292cc537 [ThinLTO] Add correctness check for RO/WO variable import
This patch adds an assertion check for exported read/write-only
variables to be also in import list for module. If they aren't
we may face linker errors, because read/write-only variables are
internalized in their source modules. The patch also changes
export lists to store ValueInfo instead of GUID for performance
considerations.

Differential revision: https://reviews.llvm.org/D70128
2019-11-14 12:24:05 +03:00
Dimitry Andric 3db6783d8a Check result of emitStrLen before passing it to CreateGEP
Summary:
This fixes PR43081, where the transformation of `strchr(p, 0) -> p +
strlen(p)` can cause a segfault, if `-fno-builtin-strlen` is used.  In
that case, `emitStrLen` returns nullptr, which CreateGEP is not designed
to handle.  Also add the minimized code from the PR as a test case.

Reviewers: xbolva00, spatel, jdoerfert, efriedma

Reviewed By: efriedma

Subscribers: lebedev.ri, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D70143
2019-11-14 08:04:36 +01:00
Reid Kleckner 05da2fe521 Sink all InitializePasses.h includes
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
  recompiles    touches affected_files  header
  342380        95      3604    llvm/include/llvm/ADT/STLExtras.h
  314730        234     1345    llvm/include/llvm/InitializePasses.h
  307036        118     2602    llvm/include/llvm/ADT/APInt.h
  213049        59      3611    llvm/include/llvm/Support/MathExtras.h
  170422        47      3626    llvm/include/llvm/Support/Compiler.h
  162225        45      3605    llvm/include/llvm/ADT/Optional.h
  158319        63      2513    llvm/include/llvm/ADT/Triple.h
  140322        39      3598    llvm/include/llvm/ADT/StringRef.h
  137647        59      2333    llvm/include/llvm/Support/Error.h
  131619        73      1803    llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211
2019-11-13 16:34:37 -08:00
Hiroshi Yamauchi 3f0969daf9 [PGO][PGSO] Temporarily disable the large working set size behavior.
Summary:
This temporarily disables the large working set size behavior in profile guided
size optimization due to internal benchmark regressions.

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70207
2019-11-13 14:00:47 -08:00
Francesco Petrogalli e9a06e0606 [VFABI] Read/Write functions for the VFABI attribute.
The attribute is stored at the `FunctionIndex` attribute set, with the
name "vector-function-abi-variant".

The get/set methods of the attribute have assertion to verify that:

1. Each name in the attribute is a valid VFABI mangled name.

2. Each name in the attribute correspond to a function declared in the
   module.

Differential Revision: https://reviews.llvm.org/D69976
2019-11-12 03:40:42 +00:00
evgeny 7f92d66f37 [ThinLTO] Fix bug when importing writeonly variables
Patch enables import of write-only variables with non-trivial initializers
to fix linker errors. Initializers of imported variables are converted to
'zeroinitializer' to avoid promotion of referenced objects.

Differential revision: https://reviews.llvm.org/D70006
2019-11-08 20:50:34 +03:00
Daniel Sanders 25ee861372 [debugify] Move the Debugify pass from tools/opt to lib/Transform/Utils
Summary:
I need to make use of this pass from a driver program that isn't opt.
Therefore this patch moves this pass into the LLVM library so that it is
available for use elsewhere.

There was one function I kept in tools/opt which is exportDebugifyStats()
this is because it's serializing the statistics into a human readable
format and this seemed more in keeping with opt than a library function

Reviewers: vsk, aprantl

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69926
2019-11-07 14:41:54 -08:00
Vedant Kumar a087b78bc4 Wrong debug info generated at -O2 (-O0 is correct)
Instcombiner pass was erasing trivially dead instruction without updating dependent llvm.dbg.value.
which was not showing programmer current state of variables while debugging.
As a part of this fix I did following,
Iterate throught all the users (llvm.dbg) of a instruction which is trivially dead and set each if them undef, Before deleting the instruction.
Now user will see optimized out, when try to print those variables.
This fixes
https://bugs.llvm.org/show_bug.cgi?id=43893

This is my first fix to llvm.

Patch by kamlesh kumar!

Differential Revision: https://reviews.llvm.org/D69809
2019-11-07 11:19:41 -08:00
evgeny dde589389f [ThinLTO] Import readonly vars with refs
Patch allows importing declarations of functions and variables, referenced
by the initializer of some other readonly variable.
Differential revision: https://reviews.llvm.org/D69561
2019-11-07 15:13:35 +03:00
Wenlei He ba1dfae054 Keep import function list for inlinee profile update
Summary:
When adjusting function entry counts after inlining, Funciton::setEntryCount is called without providing an import function list. The side effect of that is the previously set import function list will be dropped. The import function list is used by ThinLTO to help import hot cross module callee for LTO inlining, so dropping that during ThinLTO pre-link may adversely affect LTO inlining. The fix is to keep the list while updating entry counts for inlining.

Reviewers: wmi, davidxl, tejohnson

Subscribers: mehdi_amini, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69736
2019-11-06 18:36:00 -08:00
Roman Lebedev 4fe94d0331
[LoopUnroll] countToEliminateCompares(): fix handling of [in]equality predicates (PR43840)
Summary:
I believe this bisects to https://reviews.llvm.org/D44983
(`[LoopUnroll] Only peel if a predicate becomes known in the loop body.`)

While that revision did contain tests that showed arguably-subpar peeling
for [in]equality predicates that [not] happen in the middle of the loop,
it also disabled peeling for the *first* loop iteration,
because latch would be canonicalized to [in]equality comparison..

That was intentional as per https://reviews.llvm.org/D44983#1059583.
I'm not 100% sure that i'm using correct checks here,
but this fix appears to be going in the right direction..

Let me know if i'm missing some checks here..

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=43840 | PR43840 ]].

Reviewers: fhahn, mkazantsev, efriedma

Reviewed By: fhahn

Subscribers: xbolva00, hiraditya, zzheng, llvm-commits, fhahn

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69617
2019-11-06 15:08:59 +03:00
Alina Sbirlea 4b698645d3 [LoopRotationUtils] Check values are newly inserted into maps.
This is a cleanup that came up in D63680.
All values added to the ValueMaps should be newly added.
2019-11-05 13:40:10 -08:00
Philip Reames 6ff439b57f [SimplifyCFG] Use a (trivially) dominanting widenable branch to remove later slow path blocks
This transformation is a variation on the GuardWidening transformation we have checked in as it's own pass. Instead of focusing on merge (i.e. hoisting and simplifying) two widenable branches, this transform makes the observation that simply removing a second slowpath block (by reusing an existing one) is often a very useful canonicalization. This may lead to later merging, or may not. This is a useful generalization when the intermediate block has loads whose dereferenceability is hard to establish.

As noted in the patch, this can be generalized further, and will be.

Differential Revision: https://reviews.llvm.org/D69689
2019-11-04 11:03:28 -08:00
Amy Huang ab76cfdd20 Recommit "[CodeView] Add option to disable inline line tables."
This reverts commit 004ed2b0d1.
Original commit hash 6d03890384

Summary:
This adds a clang option to disable inline line tables. When it is used,
the inliner uses the call site as the location of the inlined function instead of
marking it as an inline location with the function location.

https://reviews.llvm.org/D67723
2019-11-04 09:15:26 -08:00
Dávid Bolvanský 914128ab12 [LoopUnrollRuntime] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:05:18 +01:00
Dávid Bolvanský 60cb193a40 [LoopUnrollAndJam] Fixed null check after dereferencing warning. NFCI. 2019-11-03 20:02:54 +01:00
Teresa Johnson 16ec00eee7 Recommit "[ThinLTO] Handle GUID collision in import global processing""
This recommits cc0b9647b7 which was
reverted in d39d1a2f87.

I added a fix for an issue found when testing via distributed ThinLTO,
and added a test case for that failure.
2019-11-01 13:57:01 -07:00
Teresa Johnson d39d1a2f87 Revert "[LLD][ThinLTO] Handle GUID collision in import global processing"
This reverts commit cc0b9647b7.

The commit is causing a failure in internal testing. Will recommit with
a fix later.
2019-11-01 10:02:58 -07:00
Amy Huang 004ed2b0d1 Revert "[CodeView] Add option to disable inline line tables."
because it breaks compiler-rt tests.

This reverts commit 6d03890384.
2019-10-30 17:31:12 -07:00
Amy Huang 6d03890384 [CodeView] Add option to disable inline line tables.
Summary:
This adds a clang option to disable inline line tables. When it is used,
the inliner uses the call site as the location of the inlined function instead of
marking it as an inline location with the function location.

See https://bugs.llvm.org/show_bug.cgi?id=42344

Reviewers: rnk

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67723
2019-10-30 16:52:39 -07:00
Florian Hahn 596e4ab97a [LCSSA] Forget values we create LCSSA phis for
Summary:
Currently we only forget the loop we added LCSSA phis for. But SCEV
expressions in other loops could also depend on the instruction we added
a PHI for and currently we do not invalidate those expressions. This can
happen when we use ScalarEvolution before converting a function to LCSSA
form. The SCEV expressions will refer to the non-LCSSA value. If this
SCEV expression is then used with the expander, we do not preserve LCSSA
form.

This patch properly forgets the values we created PHIs for. Those need
to be recomputed again. This patch fixes PR43458.

Currently SCEV::verify does not catch this mismatch and any test would
need to run multiple passes to trigger the error (e.g. -loop-reduce
-loop-unroll). I will also look into catching this kind of mismatch in
the verifier. Also, we currently forget the whole loop in LCSSA and I'll
check if we can be more surgical.

Reviewers: efriedma, sanjoy.google, reames

Reviewed By: efriedma

Subscribers: zzheng, hiraditya, javed.absar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68194
2019-10-29 12:05:09 +00:00
Hiroshi Yamauchi 75f72f6b73 [PGO][PGSO] SizeOpts changes.
Summary:
(Split of off D67120)

SizeOpts/MachineSizeOpts changes for profile guided size optimization.

(A second try after previously committed as r375254 and reverted as r375375.)

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69409
2019-10-28 12:57:26 -07:00
Bjorn Pettersson 80cb2cecc6 [utils] InlineFunction: fix for debug info affecting optimizations
Summary:
Debug info affects output from "opt -inline", InlineFunction could
not handle the llvm.dbg.value when it exist between alloca
instructions.

Problem was that the first alloca in a sequence of allocas was
handled differently from the subsequence alloca instructions. Now
all static alloca instructions are treated the same (being removed
if the have no uses). So it does not matter if there are dbg
instructions (or any other instructions) in between.

Fix the issue: https://bugs.llvm.org/show_bug.cgi?id=43291k

Patch by: yechunliang (Chris Ye)

Reviewers: bjope, jmorse, vsk, probinson, jdoerfert, mtrofin, aprantl, fhahn

Reviewed By: bjope

Subscribers: uabelho, ormris, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68633
2019-10-28 18:19:07 +01:00
Guillaume Chatelet e8a0a0904b [Alignment][NFC] Convert AllocaInst to MaybeAlign
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Reviewed By: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69301
2019-10-25 22:41:34 +02:00
Teresa Johnson cc0b9647b7 [LLD][ThinLTO] Handle GUID collision in import global processing
Summary:
If there are a GUID collision between two globals checking the
summarylist from the import index to make assumption can be dangerous.

Do not assume that a GlobalValue that has a GlobalVarSummary
actually is a GlobalVariable as it can be another GlobalValue with
the same GUID that the summary is connected to.

Patch by Joel Klinghed (the_jk@opera.com)

Reviewers: evgeny777, tejohnson

Reviewed By: tejohnson

Subscribers: tejohnson, dblaikie, MaskRay, mehdi_amini, inglorion, hiraditya, steven_wu, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67322
2019-10-25 12:36:01 -07:00
Bjorn Pettersson 1f43ea41c3 Prune Pass.h include from DataLayout.h. NFCI
Summary:
Reduce include dependencies by no longer including Pass.h from
DataLayout.h. That include seemed irrelevant to DataLayout, as
well as being irrelevant to several users of DataLayout.

Reviewers: rnk

Reviewed By: rnk

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

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69261

llvm-svn: 375436
2019-10-21 17:51:54 +00:00
Guillaume Chatelet 301b4128ac [Alignment][NFC] Finish transition for `Loads`
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, asbirlea, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69253

llvm-svn: 375419
2019-10-21 15:10:26 +00:00
Vladimir Vereschaka 92c96c7bc0 Reverted r375254 as it has broken some build bots for a long time.
llvm-svn: 375375
2019-10-20 20:39:33 +00:00
Hiroshi Yamauchi 7e1637451d [PGO][PGSO] SizeOpts changes.
Summary:
(Split of off D67120)

SizeOpts/MachineSizeOpts changes for profile guided size optimization.

Reviewers: davidxl

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69070

llvm-svn: 375254
2019-10-18 16:46:01 +00:00
Alina Sbirlea 4eb1a573fa [Utils] Cleanup similar cases to MergeBlockIntoPredecessor.
Summary:
There are two cases where a block is merged into its predecessor and the
MergeBlockIntoPredecessor API is not used. Update the API so it can be
reused in the other cases, in order to avoid code duplication.

Cleanup motivated by D68659.

Reviewers: chandlerc, sanjoy.google, george.burgess.iv

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68670

llvm-svn: 375050
2019-10-16 22:23:20 +00:00
Aditya Kumar 9d10b9d99b CodeExtractor: NFC: Use Range based loop
Reviewers: vsk, tejohnson, fhahn

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68924

llvm-svn: 374963
2019-10-16 01:50:21 +00:00
Guillaume Chatelet 0e62011df8 [Alignment][NFC] Remove dependency on GlobalObject::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, mehdi_amini, jvesely, nhaehnle, hiraditya, steven_wu, dexonsmith, dang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68944

llvm-svn: 374880
2019-10-15 11:24:36 +00:00
Evandro Menezes 8bd4276981 [InstCombine] Add test case for PR43617 (NFC)
Also, refactor check in `LibCallSimplifier::optimizeLog()`.

llvm-svn: 374453
2019-10-10 21:29:10 +00:00
Evandro Menezes d2f4c452d9 [InstCombine] Fix PR43617
Check for `nullptr` before inspecting composite function.

llvm-svn: 374243
2019-10-09 22:03:23 +00:00
Evandro Menezes e60415a0db [Support] Add mathematical constants
Add own version of the mathematical constants from the upcoming C++20 `std::numbers`.

Differential revision: https://reviews.llvm.org/D68257

llvm-svn: 374207
2019-10-09 19:58:01 +00:00
Alina Sbirlea 7faa14a98b [MemorySSA] Make the use of moveAllAfterMergeBlocks consistent.
Summary:
The rule for the moveAllAfterMergeBlocks API si for all instructions
from `From` to have been moved to `To`, while keeping the CFG edges (and
block terminators) unchanged.
Update all the callsites for moveAllAfterMergeBlocks to follow this.

Pending follow-up: since the same behavior is needed everytime, merge
all callsites into one. The common denominator may be the call to
`MergeBlockIntoPredecessor`.

Resolves PR43569.

Reviewers: george.burgess.iv

Subscribers: Prazek, sanjoy.google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68659

llvm-svn: 374177
2019-10-09 15:54:24 +00:00
Vedant Kumar 9852699dcb [CodeExtractor] Factor out and reuse shrinkwrap analysis
Factor out CodeExtractor's analysis of allocas (for shrinkwrapping
purposes), and allow the analysis to be reused.

This resolves a quadratic compile-time bug observed when compiling
AMDGPUDisassembler.cpp.o.

Pre-patch (Release + LTO clang):

```
   ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
  176.5278 ( 57.8%)   0.4915 ( 18.5%)  177.0192 ( 57.4%)  177.4112 ( 57.3%)  Hot Cold Splitting
```

Post-patch (ReleaseAsserts clang):

```
   ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
  1.4051 (  3.3%)   0.0079 (  0.3%)   1.4129 (  3.2%)   1.4129 (  3.2%)  Hot Cold Splitting
```

Testing: check-llvm, and comparing the AMDGPUDisassembler.cpp.o binary
pre- vs. post-patch.

An alternate approach is to hide CodeExtractorAnalysisCache from clients
of CodeExtractor, and to recompute the analysis from scratch inside of
CodeExtractor::extractCodeRegion(). This eliminates some redundant work
in the shrinkwrapping legality check. However, some clients continue to
exhibit O(n^2) compile time behavior as computing the analysis is O(n).

rdar://55912966

Differential Revision: https://reviews.llvm.org/D68616

llvm-svn: 374089
2019-10-08 17:17:51 +00:00
Jordan Rose fdaa742174 Second attempt to add iterator_range::empty()
Doing this makes MSVC complain that `empty(someRange)` could refer to
either C++17's std::empty or LLVM's llvm::empty, which previously we
avoided via SFINAE because std::empty is defined in terms of an empty
member rather than begin and end. So, switch callers over to the new
method as it is added.

https://reviews.llvm.org/D68439

llvm-svn: 373935
2019-10-07 18:14:24 +00:00
Aditya Kumar 6a2673605e Invalidate assumption cache before outlining.
Subscribers: llvm-commits

Tags: #llvm

Reviewers: compnerd, vsk, sebpop, fhahn, tejohnson

Reviewed by: vsk

Differential Revision: https://reviews.llvm.org/D68478

llvm-svn: 373807
2019-10-04 22:46:42 +00:00
Guillaume Chatelet d400d45150 [Alignment][NFC] Remove StoreInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, bollu, jdoerfert

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

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68268

llvm-svn: 373595
2019-10-03 13:17:21 +00:00
David Bolvansky 6b45029676 [InstCombine] Transform bcopy to memmove
bcopy is still widely used mainly for network apps. Sadly, LLVM has no optimizations for bcopy, but there are some for memmove. 
Since bcopy == memmove, it is profitable to transform bcopy to memmove and use current optimizations for memmove for free here.

llvm-svn: 373537
2019-10-02 22:49:20 +00:00
Florian Hahn a80b6c1542 [Local] Handle terminators with users in removeUnreachableBlocks.
Terminators like invoke can have users outside the current basic block.
We have to replace those users with undef, before replacing the
terminator.

This fixes a crash exposed by rL373430.

Reviewers: brzycki, asbirlea, davide, spatel

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D68327

llvm-svn: 373513
2019-10-02 19:38:24 +00:00
Florian Hahn eb6700b57e [Local] Remove unused LazyValueInfo pointer from removeUnreachableBlock.
There are no users that pass in LazyValueInfo, so we can simplify the
function a bit.

Reviewers: brzycki, asbirlea, davide

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D68297

llvm-svn: 373488
2019-10-02 16:58:13 +00:00
Aditya Kumar c4a7b912c2 [CodeExtractor] NFC: Refactor sanity checks into isEligible
Reviewers: fhahn

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68331

llvm-svn: 373479
2019-10-02 15:36:39 +00:00
Aditya Kumar b1fe6c90e6 NFC: directly return when CommonExitBlock != Succ
Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68330

llvm-svn: 373456
2019-10-02 12:15:17 +00:00
Florian Hahn 167b0529be [Local] Simplify function removeUnreachableBlocks() to avoid (re-)computation.
Two small changes in llvm::removeUnreachableBlocks() to avoid unnecessary (re-)computation.

First, replace the use of count() with find(), which has better time complexity.

Second, because we have already computed the set of dead blocks, replace the second loop over all basic blocks to a loop only over the already computed dead blocks. This simplifies the loop and avoids recomputation.

Patch by Rodrigo Caetano Rocha <rcor.cs@gmail.com>

Reviewers: efriedma, spatel, fhahn, xbolva00

Reviewed By: fhahn, xbolva00

Differential Revision: https://reviews.llvm.org/D68191

llvm-svn: 373429
2019-10-02 07:37:41 +00:00
Sanjay Patel 9738fd6387 [BypassSlowDivision][CodeGenPrepare] avoid crashing on unused code (PR43514)
https://bugs.llvm.org/show_bug.cgi?id=43514

llvm-svn: 373394
2019-10-01 21:25:36 +00:00
David Bolvansky 4037582d6b Revert [InstCombine] sprintf(dest, "%s", str) -> memccpy(dest, str, 0, MAX)
Seems to be slower than memcpy + strlen.

llvm-svn: 373335
2019-10-01 13:19:04 +00:00
David Bolvansky 8fc6a1bf56 [InstCombine] sprintf(dest, "%s", str) -> memccpy(dest, str, 0, MAX)
llvm-svn: 373333
2019-10-01 13:03:10 +00:00
Evandro Menezes 41ead4281f [SimplifyLibCalls] Define the value of the Euler number
This patch fixes the build break on Windows hosts.

There must be a better way of accessing the equivalent POSIX math constant
`M_E`.

llvm-svn: 373274
2019-09-30 23:21:02 +00:00
Evandro Menezes 110b1138ba [InstCombine] Expand the simplification of log()
Expand the simplification of special cases of `log()` to include `log2()`
and `log10()` as well as intrinsics and more types.

Differential revision: https://reviews.llvm.org/D67199

llvm-svn: 373261
2019-09-30 20:52:21 +00:00
David Bolvansky a05e671c7e [FunctionAttrs] Added noalias for memccpy/mempcpy arguments
llvm-svn: 373251
2019-09-30 19:43:48 +00:00
Guillaume Chatelet ab11b9188d [Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207
2019-09-30 13:34:44 +00:00
Guillaume Chatelet 17380227e8 [Alignment][NFC] Remove LoadInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, jdoerfert

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

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68142

llvm-svn: 373195
2019-09-30 09:37:05 +00:00
Simon Pilgrim 2e0de86808 ModuleUtils - silence static analyzer dyn_cast<> null dereference warning. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<> directly and if not assert will fire for us.

llvm-svn: 373099
2019-09-27 16:55:49 +00:00
Simon Pilgrim f71f23d14d FunctionImportGlobalProcessing::processGlobalForThinLTO - silence static analyzer dyn_cast<FunctionSummary> null dereference warning. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<FunctionSummary> directly and if not assert will fire for us.

llvm-svn: 373097
2019-09-27 15:49:19 +00:00
Guillaume Chatelet 18f805a7ea [Alignment][NFC] Remove unneeded llvm:: scoping on Align types
llvm-svn: 373081
2019-09-27 12:54:21 +00:00
Jakub Kuderski d98cb81cd1 Handle successor's PHI node correctly when flattening CFG merges two if-regions
Summary:
FlattenCFG merges two 'if' basicblocks by inserting one basicblock
to another basicblock. The inserted basicblock can have a successor
that contains a PHI node whoes incoming basicblock is the inserted
basicblock. Since the existing code does not handle it, it becomes
a badref.

if (cond1)
  statement
if (cond2)
  statement
successor - contains PHI node whose predecessor is cond2

-->
if (cond1 || cond2)
  statement
(BB for cond2 was deleted)
successor - contains PHI node whose predecessor is cond2 --> bad ref!

Author: Jaebaek Seo

Reviewers: asbirlea, kuhar, tstellar, chandlerc, davide, dexonsmith

Reviewed By: kuhar

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68032

llvm-svn: 372989
2019-09-26 15:20:17 +00:00
Simon Pilgrim c15cd009ac [FlattenCFG] Silence static analyzer dyn_cast<BranchInst> null dereference warnings. NFCI.
The static analyzer is warning about a potential null dereferences, but we should be able to use cast<BranchInst> directly and if not assert will fire for us.

llvm-svn: 372977
2019-09-26 13:33:15 +00:00
Simon Pilgrim b6d11def37 [SimplifyCFG] FoldTwoEntryPHINode - silence static analyzer null dereference warning. NFCI.
Assert that we've found the DomBlock.

llvm-svn: 372728
2019-09-24 11:17:20 +00:00
Simon Pilgrim 9e8076b219 SimplifyCFG - silence static analyzer dyn_cast<LandingPadInst> null dereference warning. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<LandingPadInst> directly and if not assert will fire for us.

llvm-svn: 372727
2019-09-24 11:17:13 +00:00
Simon Pilgrim bc58230e29 SimplifyCFG - silence static analyzer dyn_cast<Instruction> null dereference warning. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<Instruction> directly and if not assert will fire for us.

llvm-svn: 372726
2019-09-24 11:17:06 +00:00
David Bolvansky 8d52016155 [SLC] Convert some strndup calls to strdup calls
Summary:
Motivation:
- If we can fold it to strdup, we should (strndup does more things than strdup).
- Annotation mechanism. (Works for strdup well).

strdup and strndup are part of C 20 (currently posix fns), so we should optimize them.

Reviewers: efriedma, jdoerfert

Reviewed By: jdoerfert

Subscribers: lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67679

llvm-svn: 372636
2019-09-23 18:20:01 +00:00
Roman Lebedev feea722cf3 [SimplifyCFG] mergeConditionalStoreToAddress(): try to pacify MSAN
MSAN bot complains that there is use-of-uninitialized-value
of this FreeStores later in IsWorthwhile().
Perhaps FreeStores needs to be stored in a vector?

llvm-svn: 372262
2019-09-18 21:04:39 +00:00
Roman Lebedev dd0170ab24 [SimplifyCFG] mergeConditionalStoreToAddress(): consider cost, not instruction count
Summary:
As it can be see in the changed test, while `div` is really costly,
we were speculating it. This does not seem correct.

Also, the old code would run for every single insturuction in BB,
instead of eagerly bailing out as soon as there are too many instructions.

This function still has a problem that `PHINodeFoldingThreshold` is
per-basic-block, while it should be for all the basic blocks.

Reviewers: efriedma, craig.topper, dmgreen, jmolloy

Reviewed By: jmolloy

Subscribers: xbolva00, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67315

llvm-svn: 372255
2019-09-18 19:46:57 +00:00
Sanjay Patel d46bf63fbb [SimplifyLibCalls] fix crash with empty function name (PR43347)
...and improve some variable names while here.

https://bugs.llvm.org/show_bug.cgi?id=43347

llvm-svn: 372227
2019-09-18 14:33:40 +00:00
David Bolvansky 0c0de794f1 Reland "[SLC] Preserve attrs for strncpy(x, "", y) -> memset(align 1 x, '\0', y)"
llvm-svn: 372142
2019-09-17 17:12:24 +00:00
Krasimir Georgiev bdff164e0e Revert "[SLC] Preserve attrs for strncpy(x, "", y) -> memset(align 1 x, '\0', y)"
Summary:
This reverts commit r372101.

Causes ASAN build bot failures:

http://lab.llvm.org:8011/builders/sanitizer-ppc64be-linux/builds/14176
From http://lab.llvm.org:8011/builders/sanitizer-ppc64be-linux/builds/14176/steps/64-bit%20check-asan/logs/stdio:

```
[ RUN      ] AddressSanitizer.StrNCatOOBTest
/home/buildbots/ppc64be-sanitizer/sanitizer-ppc64be/build/llvm-project/compiler-rt/lib/asan/tests/asan_str_test.cpp:462: Failure
Death test: strncat(to - 1, from, 0)
    Result: failed to die.
```

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67658

llvm-svn: 372125
2019-09-17 14:15:23 +00:00
David Bolvansky ded48e93e6 [SLC] Preserve attrs for strncpy(x, "", y) -> memset(align 1 x, '\0', y)
llvm-svn: 372101
2019-09-17 10:25:38 +00:00
David Bolvansky 3a3dddd9d7 [NFCI] Fixed buildbots
llvm-svn: 372097
2019-09-17 10:03:45 +00:00
Fangrui Song 8351763709 [SimplifyLibCalls] Fix -Wunused-result after D53342/r372091
llvm-svn: 372096
2019-09-17 09:56:55 +00:00
David Bolvansky e80fcf0340 [SimplifyLibCalls] Mark known arguments with nonnull
Reviewers: efriedma, jdoerfert

Reviewed By: jdoerfert

Subscribers: ychen, rsmith, joerg, aaron.ballman, lebedev.ri, uenoku, jdoerfert, hfinkel, javed.absar, spatel, dmgreen, llvm-commits

Differential Revision: https://reviews.llvm.org/D53342

llvm-svn: 372091
2019-09-17 09:32:52 +00:00
Roman Lebedev 10151f6618 [SimplifyCFG] FoldTwoEntryPHINode(): consider *total* speculation cost, not per-BB cost
Summary:
Previously, if the threshold was 2, we were willing to speculatively
execute 2 cheap instructions in both basic blocks (thus we were willing
to speculatively execute cost = 4), but weren't willing to speculate
when one BB had 3 instructions and other one had no instructions,
even thought that would have total cost of 3.

This looks inconsistent to me.
I don't think `cmov`-like instructions will start executing
until both of it's inputs are available: https://godbolt.org/z/zgHePf
So i don't see why the existing behavior is the correct one.

Also, let's add it's own `cl::opt` for this threshold,
with default=4, so it is not stricter than the previous threshold:
will allow to fold when there are 2 BB's each with cost=2.
And since the logic has changed, it will also allow to fold when
one BB has cost=3 and other cost=1, or there is only one BB with cost=4.

This is an alternative solution to D65148:
This fix is mainly motivated by `signbit-like-value-extension.ll` test.
That pattern comes up in JPEG decoding, see e.g.
`Figure F.12 – Extending the sign bit of a decoded value in V`
of `ITU T.81` (JPEG specification).
That branch is not predictable, and it is within the innermost loop,
so the fact that that pattern ends up being stuck with a branch
instead of `select` (i.e. `CMOV` for x86) is unlikely to be beneficial.

This has great results on the final assembly (vanilla test-suite + RawSpeed): (metric pass - D67240)
| metric                                 |     old |     new | delta |      % |
| x86-mi-counting.NumMachineFunctions    |   37720 |   37721 |     1 |  0.00% |
| x86-mi-counting.NumMachineBasicBlocks  |  773545 |  771181 | -2364 | -0.31% |
| x86-mi-counting.NumMachineInstructions | 7488843 | 7486442 | -2401 | -0.03% |
| x86-mi-counting.NumUncondBR            |  135770 |  135543 |  -227 | -0.17% |
| x86-mi-counting.NumCondBR              |  423753 |  422187 | -1566 | -0.37% |
| x86-mi-counting.NumCMOV                |   24815 |   25731 |   916 |  3.69% |
| x86-mi-counting.NumVecBlend            |      17 |      17 |     0 |  0.00% |

We significantly decrease basic block count, notably decrease instruction count,
significantly decrease branch count and very significantly increase `cmov` count.

Performance-wise, unsurprisingly, this has great effect on
target RawSpeed benchmark. I'm seeing 5 **major** improvements:
```
Benchmark                                                                                             Time             CPU      Time Old      Time New       CPU Old       CPU New
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_pvalue                                 0.0000          0.0000      U Test, Repetitions: 49 vs 49
Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_mean                                  -0.3064         -0.3064      226.9913      157.4452      226.9800      157.4384
Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_median                                -0.3057         -0.3057      226.8407      157.4926      226.8282      157.4828
Samsung/NX3000/_3184416.SRW/threads:8/process_time/real_time_stddev                                -0.4985         -0.4954        0.3051        0.1530        0.3040        0.1534
Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_pvalue                                  0.0000          0.0000      U Test, Repetitions: 49 vs 49
Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_mean                                   -0.1747         -0.1747       80.4787       66.4227       80.4771       66.4146
Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_median                                 -0.1742         -0.1743       80.4686       66.4542       80.4690       66.4436
Kodak/DCS760C/86L57188.DCR/threads:8/process_time/real_time_stddev                                 +0.6089         +0.5797        0.0670        0.1078        0.0673        0.1062
Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_pvalue                                 0.0000          0.0000      U Test, Repetitions: 49 vs 49
Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_mean                                  -0.1598         -0.1598      171.6996      144.2575      171.6915      144.2538
Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_median                                -0.1598         -0.1597      171.7109      144.2755      171.7018      144.2766
Sony/DSLR-A230/DSC08026.ARW/threads:8/process_time/real_time_stddev                                +0.4024         +0.3850        0.0847        0.1187        0.0848        0.1175
Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_pvalue                                  0.0000          0.0000      U Test, Repetitions: 49 vs 49
Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_mean                                   -0.0550         -0.0551      280.3046      264.8800      280.3017      264.8559
Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_median                                 -0.0554         -0.0554      280.2628      264.7360      280.2574      264.7297
Canon/EOS 77D/IMG_4049.CR2/threads:8/process_time/real_time_stddev                                 +0.7005         +0.7041        0.2779        0.4725        0.2775        0.4729
Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_pvalue                                  0.0000          0.0000      U Test, Repetitions: 49 vs 49
Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_mean                                   -0.0354         -0.0355      316.7396      305.5208      316.7342      305.4890
Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_median                                 -0.0354         -0.0356      316.6969      305.4798      316.6917      305.4324
Canon/EOS 5DS/2K4A9929.CR2/threads:8/process_time/real_time_stddev                                 +0.0493         +0.0330        0.3562        0.3737        0.3563        0.3681
```

That being said, it's always best-effort, so there will likely
be cases where this worsens things.

Reviewers: efriedma, craig.topper, dmgreen, jmolloy, fhahn, Carrot, hfinkel, chandlerc

Reviewed By: jmolloy

Subscribers: xbolva00, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67318

llvm-svn: 372009
2019-09-16 16:18:24 +00:00
Florian Hahn cde8343d85 [BasicBlockUtils] Add optional BBName argument, in line with BB:splitBasicBlock
Reviewers: spatel, asbirlea, craig.topper

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D67521

llvm-svn: 371819
2019-09-13 08:03:32 +00:00
Petr Hosek 7bdad08429 Reland "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371635
2019-09-11 16:19:50 +00:00
Dmitri Gribenko 57256af307 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371584. It introduced a dependency from compiler-rt
to llvm/include/ADT, which is problematic for multiple reasons.

One is that it is a novel dependency edge, which needs cross-compliation
machinery for llvm/include/ADT (yes, it is true that right now
compiler-rt included only header-only libraries, however, if we allow
compiler-rt to depend on anything from ADT, other libraries will
eventually get used).

Secondly, depending on ADT from compiler-rt exposes ADT symbols from
compiler-rt, which would cause ODR violations when Clang is built with
the profile library.

llvm-svn: 371598
2019-09-11 09:16:17 +00:00
Petr Hosek 394a8ed8f1 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371584
2019-09-11 01:09:16 +00:00
Alina Sbirlea f9cc0393b3 [MemorySSA] MemorySSA should not model debuginfo, and need not update it.
Reverts the change in r371084, but keeps the test.
After r371565, debuginfo cannot be modelled in MemorySSA, even with a
non-standard AA pipeline.

llvm-svn: 371573
2019-09-10 23:36:43 +00:00
Petr Hosek 7d1757aba8 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371484: this broke sanitizer-x86_64-linux-fast bot.

llvm-svn: 371488
2019-09-10 06:25:13 +00:00
Petr Hosek a10802fd73 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371484
2019-09-10 03:11:39 +00:00
Roman Lebedev 45ba26599b [SimplifyCFG] SpeculativelyExecuteBB(): It's SpeculatedInstructions, not SpeculationCost
It counts the number of instructions we are ok speculating
(at most 1 there), not their cost, so rename accordingly.

llvm-svn: 371294
2019-09-07 09:06:06 +00:00
Teresa Johnson 9c27b59cec Change TargetLibraryInfo analysis passes to always require Function
Summary:
This is the first change to enable the TLI to be built per-function so
that -fno-builtin* handling can be migrated to use function attributes.
See discussion on D61634 for background. This is an enabler for fixing
handling of these options for LTO, for example.

This change should not affect behavior, as the provided function is not
yet used to build a specifically per-function TLI, but rather enables
that migration.

Most of the changes were very mechanical, e.g. passing a Function to the
legacy analysis pass's getTLI interface, or in Module level cases,
adding a callback. This is similar to the way the per-function TTI
analysis works.

There was one place where we were looking for builtins but not in the
context of a specific function. See FindCXAAtExit in
lib/Transforms/IPO/GlobalOpt.cpp. I'm somewhat concerned my workaround
could provide the wrong behavior in some corner cases. Suggestions
welcome.

Reviewers: chandlerc, hfinkel

Subscribers: arsenm, dschuff, jvesely, nhaehnle, mehdi_amini, javed.absar, sbc100, jgravelle-google, eraman, aheejin, steven_wu, george.burgess.iv, dexonsmith, jfb, asbirlea, gchatelet, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66428

llvm-svn: 371284
2019-09-07 03:09:36 +00:00
Evandro Menezes 7d677adf2d [InstCombine] Refactor substitution of instruction in the parent BB (NFC)
Add the new method `LibCallSimplifier::substituteInParent()` that calls
`LibCallSimplifier::replaceAllUsesWith()' and
`LibCallSimplifier::eraseFromParent()` back to back, simplifying the
resulting code.

llvm-svn: 371264
2019-09-06 22:07:11 +00:00
Sanjay Patel 4f0e429acc [SimplifyLibCalls] handle pow(x,-0.0) before it can assert (PR43233)
https://bugs.llvm.org/show_bug.cgi?id=43233

llvm-svn: 371221
2019-09-06 16:10:18 +00:00
Vitaly Buka 9020f11377 [SimplifyCFG] Don't SimplifyBranchOnICmpChain with ExtraCase
Summary:
Here we try to avoid issues with "explicit branch" with SimplifyBranchOnICmpChain
which can check on undef. Msan by design reports branches on uninitialized
memory and undefs, so we have false report here.

In general msan does not like when we convert

```
// If at least one of them is true we can MSAN is ok if another is undefs
if (a || b)
  return;
```
into
```
// If 'a' is undef MSAN will complain even if 'b' is true
if (a)
  return;
if (b)
  return;
```

Example

Before optimization we had something like this:
```
while (true) {
  bool maybe_undef = doStuff();

  while (true) {
    char c = getChar();
    if (c != 10 && c != 13)
     continue
    break;
  }

  // we know that c == 10 || c == 13 if we get here,
  // so msan know that branch is not affected by maybe_undef
  if (maybe_undef || c == 10 || c == 13)
    continue;
  return;
}
```

SimplifyBranchOnICmpChain will convert that into
```
while (true) {
  bool maybe_undef = doStuff();

  while (true) {
    char c = getChar();
    if (c != 10 && c != 13)
      continue;
    break;
  }

  // however msan will complain here:
  if (maybe_undef)
    continue;

  // we know that c == 10 || c == 13, so either way we will get continue
  switch(c) {
    case 10: continue;
    case 13: continue;
  }
  return;
}
```

Reviewers: eugenis, efriedma

Reviewed By: eugenis, efriedma

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67205

llvm-svn: 371138
2019-09-05 22:49:34 +00:00
Alina Sbirlea 2ac69aadb5 [MemorySSA] Verify MSSAUpdater exists.
llvm-svn: 371087
2019-09-05 16:58:15 +00:00
Alina Sbirlea ae900d3882 [MemorySSA] Update MemorySSA when removing debug.value calls.
llvm-svn: 371084
2019-09-05 16:25:24 +00:00
Alina Sbirlea 6da79ce1fe [MemorySSA] Re-enable MemorySSA use.
Differential Revision: https://reviews.llvm.org/D58311

llvm-svn: 370957
2019-09-04 19:16:04 +00:00
Philip Reames 27820f9909 [Instruction] Add hasMetadata(Kind) helper [NFC]
It's a common idiom, so let's add the obvious wrapper for metadata kinds which are basically booleans.

llvm-svn: 370933
2019-09-04 17:28:48 +00:00
Alexey Lapshin cbf1f3b771 [Debuginfo][SROA] Need to handle dbg.value in SROA pass.
SROA pass processes debug info incorrecly if applied twice.
Specifically, after SROA works first time, instcombine converts dbg.declare
intrinsics into dbg.value. Inlining creates new opportunities for SROA,
so it is called again. This time it does not handle correctly previously
inserted dbg.value intrinsics.

Differential Revision: https://reviews.llvm.org/D64595

llvm-svn: 370906
2019-09-04 14:19:49 +00:00
Alina Sbirlea ccb1862bc9 [MemorySSA] Disable MemorySSA use.
Differential Revision: https://reviews.llvm.org/D58311

llvm-svn: 370821
2019-09-03 21:20:46 +00:00
Alina Sbirlea e331d50534 [MemorySSA] Re-enable MemorySSA use.
Differential Revision: https://reviews.llvm.org/D58311

llvm-svn: 370811
2019-09-03 19:28:37 +00:00
David Bolvansky ff0ad3c43d [InstCombine] mempcpy(d,s,n) to memcpy(d,s,n) + n
Summary:
Back-end currently expands mempcpy, but middle-end should work with memcpy instead of mempcpy to enable more memcpy-optimization.

GCC backend emits mempcpy, so LLVM backend could form it too, if we know mempcpy libcall is better than memcpy + n.
https://godbolt.org/z/dOCG96

Reviewers: efriedma, spatel, craig.topper, RKSimon, jdoerfert

Reviewed By: efriedma

Subscribers: hjl.tools, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65737

llvm-svn: 370593
2019-08-31 18:19:05 +00:00
Alina Sbirlea 4b87023bae Revert enabling MemorySSA.
Breaks sanitizers bots.

Differential Revision: https://reviews.llvm.org/D58311

llvm-svn: 370397
2019-08-29 19:01:23 +00:00
Florian Hahn f9cdb98f40 [LoopUnrollAndJam] Use Lazy strategy for DTU.
We can also apply the earlier updates to the lazy DTU, instead of
applying them directly.

Reviewers: kuhar, brzycki, asbirlea, SjoerdMeijer

Reviewed By: brzycki, asbirlea, SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D66918

llvm-svn: 370391
2019-08-29 17:47:58 +00:00
Alina Sbirlea 6289ee941d [MemorySSA & LoopPassManager] Enable MemorySSA as loop dependency. Update tests.
Summary:
I'm not planning to check this in at the moment, but feedback is very welcome, in particular how this affects performance.
The feedback obtains here will guide the next steps towards enabling this.

This patch enables the use of MemorySSA in the loop pass manager.

Passes that currently use MemorySSA:
 - EarlyCSE
Passes that use MemorySSA after this patch:
 - EarlyCSE
 - LICM
 - SimpleLoopUnswitch
Loop passes that update MemorySSA (and do not use it yet, but could use it after this patch):
 - LoopInstSimplify
 - LoopSimplifyCFG
 - LoopUnswitch
 - LoopRotate
 - LoopSimplify
 - LCSSA
Loop passes that do *not* update MemorySSA:
 - IndVarSimplify
 - LoopDelete
 - LoopIdiom
 - LoopSink
 - LoopUnroll
 - LoopInterchange
 - LoopUnrollAndJam
 - LoopVectorize
 - LoopReroll
 - IRCE

Reviewers: chandlerc, george.burgess.iv, davide, sanjoy, gberry

Subscribers: jlebar, Prazek, dmgreen, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58311

llvm-svn: 370384
2019-08-29 17:08:13 +00:00
Michael Liao 001871dee8 [SimplifyCFG] Skip sinking common lifetime markers of `alloca`.
Summary:
- Similar to the workaround in fix of PR30188, skip sinking common
  lifetime markers of `alloca`. They are mostly left there after
  inlining functions in branches.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66950

llvm-svn: 370376
2019-08-29 16:12:05 +00:00
Roman Lebedev 9f35d2b564 [SimplifyCFG] FoldTwoEntryPHINode(): don't bailout on i1 PHI's if we can hoist a 'not' from incoming values
Summary:
As it can be seen in the tests in D65143/D65144, even though we have formed an '@llvm.umul.with.overflow'
and got rid of potential for division-by-zero, the control flow remains, we still have that branch.

We have this condition:
```
  // Don't fold i1 branches on PHIs which contain binary operators
  // These can often be turned into switches and other things.
  if (PN->getType()->isIntegerTy(1) &&
      (isa<BinaryOperator>(PN->getIncomingValue(0)) ||
       isa<BinaryOperator>(PN->getIncomingValue(1)) ||
       isa<BinaryOperator>(IfCond)))
    return false;
```
which was added back in rL121764 to help with `select` formation i think?

That check prevents us to flatten the CFG here, even though we know
we no longer need that guard and will be able to drop everything
but the '@llvm.umul.with.overflow' + `not`.

As it can be seen from tests, we end here because the `not` is being
sinked into the PHI's incoming values by InstCombine,
so we can't workaround this by hoisting it to after PHI.

Thus i suggest that we relax that check to not bailout if we'd get to hoist the `not`.

Reviewers: craig.topper, spatel, fhahn, nikic

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65147

llvm-svn: 370349
2019-08-29 12:47:34 +00:00
Florian Hahn 3177b92231 [LoopUnroll] Use Lazy strategy for DTU used for MergeBlockIntoPredecessor.
We do not access the DT in the loop, so we do not have to apply updates
eagerly. We can apply them lazyly and flush them after we are done
merging blocks.

As follow-up work, we might be able to use the DTU above as well,
instead of manually updating the DT.

This brings the example from PR43134 from ~100s to ~4s for a relase +
assertions build on my machine.

Reviewers: efriedma, kuhar, asbirlea, brzycki

Reviewed By: kuhar, brzycki

Differential Revision: https://reviews.llvm.org/D66911

llvm-svn: 370292
2019-08-29 04:26:29 +00:00
Artur Pilipenko 925afc1ce7 Fix for "DICompileUnit not listed in llvm.dbg.cu" verification error after ...
...cloning a function from a different module

Currently when a function with debug info is cloned from a different module, the 
cloned function may have hanging DICompileUnits, so that the module with the 
cloned function fails debug info verification.

The proposed fix inserts all DICompileUnits reachable from the cloned function 
to "llvm.dbg.cu" metadata operands of the cloned function module. 

Reviewed By: aprantl, efriedma

Differential Revision: https://reviews.llvm.org/D66510

Patch by Oleg Pliss (Oleg.Pliss@azul.com)

llvm-svn: 370265
2019-08-28 21:27:50 +00:00
Pirama Arumuga Nainar 19205abaaa [ValueMapper] NFC: Remove dead code to pause metadata mapping
Summary:
This functionality was added when Mapper::mapMetadata was recursive.  It
is no longer needed after r265456, which switched it to be iterative.

Reviewers: dexonsmith, srhines

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66860

llvm-svn: 370236
2019-08-28 17:43:14 +00:00
Bjorn Pettersson d804bd17de [LoopUnroll] Handle certain PHIs in full unrolling properly
Summary:
When reconstructing the CFG of the loop after unrolling,
LoopUnroll could in some cases remove the phi operands of
loop-carried values instead of preserving them, resulting
in undef phi values after loop unrolling.

When doing this reconstruction, avoid removing incoming
phi values for phis in the successor blocks if the successor
is the block we are jumping to anyway.

Patch-by: ebevhan

Reviewers: fhahn, efriedma

Reviewed By: fhahn

Subscribers: bjope, lebedev.ri, zzheng, dmgreen, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66334

llvm-svn: 369886
2019-08-26 09:29:53 +00:00
Serguei Katkov 036e636aa7 [Loop Peeling] Fix silly bug in metadata update.
We must update loop metedata before we moved to parent loop if
it is present.

llvm-svn: 369637
2019-08-22 10:06:46 +00:00
Jian Cai 16fa8b0970 Reland "[ARM] push LR before __gnu_mcount_nc"
This relands r369147 with fixes to unit tests.

https://reviews.llvm.org/D65019

llvm-svn: 369173
2019-08-16 23:30:16 +00:00
Jian Cai 2d957cfe02 Revert "[ARM] push LR before __gnu_mcount_nc"
This reverts commit f4cf3b9593.

llvm-svn: 369149
2019-08-16 20:40:21 +00:00
Jian Cai f4cf3b9593 [ARM] push LR before __gnu_mcount_nc
Push LR register before calling __gnu_mcount_nc as it expects the value of LR register to be the top value of
the stack on ARM32.

Differential Revision: https://reviews.llvm.org/D65019

llvm-svn: 369147
2019-08-16 20:21:08 +00:00
Evandro Menezes 05e9c2ac2e [InstCombine] Simplify pow(2.0, itofp(y)) to ldexp(1.0, y)
Simplify `pow(2.0, itofp(y))` to `ldexp(1.0, y)`.

Differential revision: https://reviews.llvm.org/D65979

llvm-svn: 369120
2019-08-16 15:33:41 +00:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
David Bolvansky f94460d4b6 [SLC] Dereferenceable annonation - handle valid null pointers
Reviewers: jdoerfert, reames

Reviewed By: jdoerfert

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66161

llvm-svn: 368884
2019-08-14 17:15:20 +00:00
David Bolvansky 0e0fbae1a4 [BuildLibCalls] Noalias annotation
Summary: I think this is better solution than annotating callsites in IC/SLC.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: MaskRay, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66217

llvm-svn: 368875
2019-08-14 16:50:06 +00:00
David Bolvansky 038d604f4f [SimplifyLibCalls] Add noalias from known callsites
Summary:
Should be fine for memcpy, strcpy, strncpy.


Reviewers: jdoerfert, efriedma

Reviewed By: jdoerfert

Subscribers: uenoku, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66135

llvm-svn: 368724
2019-08-13 17:18:46 +00:00
David Bolvansky 90a30fdcc3 [SLC] Improve dereferenceable bytes annotation
llvm-svn: 368715
2019-08-13 16:44:16 +00:00
David Bolvansky 39130314fe [SimplifyLibCalls] Add dereferenceable bytes from known callsites
Summary:
int mm(char *a, char *b) {
    return memcmp(a,b,16);
}

Currently:
define dso_local i32 @mm(i8* nocapture readonly %a, i8* nocapture readonly %b) local_unnamed_addr #1 {
entry:
  %call = tail call i32 @memcmp(i8* %a, i8* %b, i64 16)
  ret i32 %call
}

After patch:
define dso_local i32 @mm(i8* nocapture readonly %a, i8* nocapture readonly %b) local_unnamed_addr #1 {
entry:
  %call = tail call i32 @memcmp(i8* dereferenceable(16)  %a, i8* dereferenceable(16)  %b, i64 16)
  ret i32 %call
}




Reviewers: jdoerfert, efriedma

Reviewed By: jdoerfert

Subscribers: javed.absar, spatel, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66079

llvm-svn: 368657
2019-08-13 09:11:49 +00:00
Evandro Menezes 59fbe516bd [InstCombine] Refactor optimizeExp2() (NFC)
Refactor `LibCallSimplifier::optimizeExp2()` to use the new
`emitBinaryFloatFnCall()` version that fetches the function name from TLI.

llvm-svn: 368457
2019-08-09 17:22:56 +00:00
Evandro Menezes 8a21214174 [Transforms] Add a emitBinaryFloatFnCall() version that fetches the function name from TLI
Add the counterpart to a similar function for single operands.

Differential revision: https://reviews.llvm.org/D65976

llvm-svn: 368453
2019-08-09 17:06:46 +00:00
Evandro Menezes c6c00cdf2e [Transforms] Rename hasUnaryFloatFn() and getUnaryFloatFn() (NFC)
Rename `hasUnaryFloatFn()` to `hasFloatFn()` and `getUnaryFloatFn()` to `getFloatFnName()`.

llvm-svn: 368449
2019-08-09 16:04:18 +00:00
Peter Collingbourne bb17e46644 Linker: Add support for GlobalIFunc.
GlobalAlias and GlobalIFunc ought to be treated the same by the IR
linker, so we can generalize the code to be in terms of their common
base class GlobalIndirectSymbol.

Differential Revision: https://reviews.llvm.org/D55046

llvm-svn: 368357
2019-08-08 22:09:18 +00:00
Tim Corringham 4f64f1ba3c Add llvm.licm.disable metadata
For some targets the LICM pass can result in sub-optimal code in some
cases where it would be better not to run the pass, but it isn't
always possible to suppress the transformations heuristically.

Where the front-end has insight into such cases it is beneficial
to attach loop metadata to disable the pass - this change adds the
llvm.licm.disable metadata to enable that.

Differential Revision: https://reviews.llvm.org/D64557

llvm-svn: 368296
2019-08-08 13:46:17 +00:00
Johannes Doerfert 3d7bbc6f9c [Attributor][Fix] Do not remove instructions during manifestation
When we remove instructions cached references could still be live. This
patch avoids removing invoke instructions that are replaced by calls and
instead keeps them around but in a dead block.

llvm-svn: 367933
2019-08-05 21:35:02 +00:00
Guillaume Chatelet 65e4b47aad [LLVM][Alignment] Introduce Alignment Type in DataLayout
Summary:
This is patch is part of a serie to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, jfb, jakehehrlich

Subscribers: hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65521

Make getFunctionPtrAlign() return MaybeAlign

llvm-svn: 367817
2019-08-05 09:00:43 +00:00
Yonghong Song 44b16bd4a5 [Transforms] Do not drop !preserve.access.index metadata
Currently, when a GVN or CSE optimization happens,
the llvm.preserve.access.index metadata is dropped.
This caused a problem for BPF AbstructMemberOffset phase
as it relies on the metadata (debuginfo types).

This patch added proper hooks in lib/Transforms to
preserve !preserve.access.index metadata. A test
case is added to ensure metadata is preserved under CSE.

Differential Revision: https://reviews.llvm.org/D65700

llvm-svn: 367769
2019-08-03 23:41:26 +00:00
Alina Sbirlea 5545e6963f [SimplifyCFG] Cleanup redundant conditions [NFC].
Summary:
Since the for loop iterates over BB's predecessors, the branch conditions found must have BB as one of the successors.
For an unconditional branch the successor must be BB, added `assert`.
For a conditional branch, one of the two successors must be BB, simplify `else if` to `else` and `assert`.
Sink common instructions outside the if/else block.

Reviewers: sanjoy.google

Subscribers: jlebar, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65596

llvm-svn: 367699
2019-08-02 18:06:54 +00:00
Serguei Katkov bbdcc82111 [Loop Peeling] Do not close further unroll/peel if profile based peeling was not used.
Current peeling cost model can decide to peel off not all iterations
but only some of them to eliminate conditions on phi. At the same time 
if any peeling happens the door for further unroll/peel optimizations on that
loop closes because the part of the code thinks that if peeling happened
it is profile based peeling and all iterations are peeled off.

To resolve this inconsistency the patch provides the flag which states whether
the full peeling basing on profile is enabled or not and peeling cost model
is able to modify this field like it does not PeelCount.

In a separate patch I will introduce an option to allow/disallow peeling basing
on profile.

To avoid infinite loop peeling the patch tracks the total number of peeled iteration
through llvm.loop.peeled.count loop metadata.

Reviewers: reames, fhahn
Reviewed By: reames
Subscribers: hiraditya, zzheng, dmgreen, llvm-commits
Differential Revision: https://reviews.llvm.org/D64972

llvm-svn: 367647
2019-08-02 04:29:23 +00:00
Alina Sbirlea 3af2a69575 [SimplifyCFG] Mark missed Changed to true.
Summary:
DominatorTree is invalid after SimplifyCFG because of a missed `Changed = true` when simplifying a branch condition and removing an edge.
Resolves PR42272.

Reviewers: zhizhouy, manojgupta

Subscribers: jlebar, sanjoy.google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65490

llvm-svn: 367596
2019-08-01 18:37:34 +00:00
Alina Sbirlea 172838df6b [MemorySSA] Set LoopSimplify to preserve MemorySSA in the NPM, if analysis exists.
Summary:
LoopSimplify is preserved in the legacy pass manager, but not in the new pass manager.
Update LoopSimplify to preserve MemorySSA conditionally when the analysis is available (same behavior as the legacy pass manager).

Reviewers: chandlerc

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65418

llvm-svn: 367594
2019-08-01 18:28:28 +00:00
Serguei Katkov 7f8c809592 [Loop Utils] Extend the scope of addStringMetadataToLoop.
To avoid duplicates in loop metadata, if the string to add is
already there, just update the value.

Reviewers: reames, Ashutosh
Reviewed By: reames
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D65265

llvm-svn: 367087
2019-07-26 07:04:34 +00:00
Serguei Katkov 3c3a76527e [Loop Utils] Move utilty addStringMetadataToLoop to LoopUtils.cpp. NFC.
Just move the utility function to LoopUtils.cpp to re-use it in loop peeling.

Reviewers: reames, Ashutosh
Reviewed By: reames
Subscribers: hiraditya, asbirlea, llvm-commits
Differential Revision: https://reviews.llvm.org/D65264

llvm-svn: 367085
2019-07-26 06:10:08 +00:00
Florian Hahn c74808b914 [PredicateInfo] Replace pointer comparisons with deterministic compares.
Currently there are a few pointer comparisons in ValueDFS_Compare, which
can cause non-deterministic ordering when materializing values. There
are 2 cases this patch fixes:

1. Order defs before uses used to compare pointers, which guarantees
   defs before uses, but causes non-deterministic ordering between 2
   uses or 2 defs, depending on the allocation order. By converting the
   pointers to booleans, we can circumvent that problem.

2. comparePHIRelated was comparing the basic block pointers of edges,
   which also results in a non-deterministic order and is also not
   really meaningful for ordering. By ordering by their destination DFS
   numbers we guarantee a deterministic order.

For the example below, we can end up with 2 different uselist orderings,
when running `opt -mem2reg -ipsccp` hundreds of times. Because the
non-determinism is caused by allocation ordering, we cannot reproduce it
with ipsccp alone.

    declare i32 @hoge() local_unnamed_addr #0

    define dso_local i32 @ham(i8* %arg, i8* %arg1) #0 {
    bb:
      %tmp = alloca i32
      %tmp2 = alloca i32, align 4
      br label %bb19

    bb4:                                              ; preds = %bb20
      br label %bb6

    bb6:                                              ; preds = %bb4
      %tmp7 = call i32 @hoge()
      store i32 %tmp7, i32* %tmp
      %tmp8 = load i32, i32* %tmp
      %tmp9 = icmp eq i32 %tmp8, 912730082
      %tmp10 = load i32, i32* %tmp
      br i1 %tmp9, label %bb11, label %bb16

    bb11:                                             ; preds = %bb6
      unreachable

    bb13:                                             ; preds = %bb20
      br label %bb14

    bb14:                                             ; preds = %bb13
      %tmp15 = load i32, i32* %tmp
      br label %bb16

    bb16:                                             ; preds = %bb14, %bb6
      %tmp17 = phi i32 [ %tmp10, %bb6 ], [ 0, %bb14 ]
      br label %bb19

    bb18:                                             ; preds = %bb20
      unreachable

    bb19:                                             ; preds = %bb16, %bb
      br label %bb20

    bb20:                                             ; preds = %bb19
      indirectbr i8* null, [label %bb4, label %bb13, label %bb18]
    }

Reviewers: davide, efriedma

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D64866

llvm-svn: 367049
2019-07-25 20:48:13 +00:00
Serguei Katkov cde00c02e1 [Loop Peeling] Fix idom detection algorithm.
We'd like to determine the idom of exit block after peeling one iteration.
Let Exit is exit block.
Let ExitingSet - is a set of predecessors of Exit block. They are exiting blocks.
Let Latch' and ExitingSet' are copies after a peeling.
We'd like to find an idom'(Exit) - idom of Exit after peeling.
It is an evident that idom'(Exit) will be the nearest common dominator of ExitingSet and ExitingSet'.
idom(Exit) is a nearest common dominator of ExitingSet.
idom(Exit)' is a nearest common dominator of ExitingSet'.
Taking into account that we have a single Latch, Latch' will dominate Header and idom(Exit).
So the idom'(Exit) is nearest common dominator of idom(Exit)' and Latch'.
All these basic blocks are in the same loop, so what we find is
(nearest common dominator of idom(Exit) and Latch)'.

Reviewers: reames, fhahn
Reviewed By: reames
Subscribers: hiraditya, zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D65292

llvm-svn: 367044
2019-07-25 19:31:50 +00:00
Sanjay Patel b456310902 [SimplifyCFG] avoid crashing after simplifying a switch (PR42737)
Later code in TryToSimplifyUncondBranchFromEmptyBlock() assumes that
we have cleaned up unreachable blocks, but that was not happening
with this switch transform.

llvm-svn: 367037
2019-07-25 17:01:12 +00:00
Florian Hahn c0d0e3bda8 [PredicateInfo] Use SmallVector instead of SmallPtrSet.
We do not need the SmallPtrSet to avoid adding duplicates to
OpsToRename, because we already keep a ValueInfo mapping. If we see an
op for the first time, Infos will be empty and we can also add it to
OpsToRename.

We process operands by visiting BBs depth-first and then iterate over
all instructions & users, so the order should be deterministic.
Therefore we can skip one round of sorting, which we purely needed for
guaranteeing a deterministic order when iterating over the SmallPtrSet.

Reviewers: efriedma, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D64816

llvm-svn: 367028
2019-07-25 15:35:10 +00:00
Sanjay Patel 38a0200868 [Utils] remove duplicated documentation comments; NFC
http://llvm.org/docs/CodingStandards.html#doxygen-use-in-documentation-comments

llvm-svn: 367015
2019-07-25 13:11:21 +00:00
Evandro Menezes 5cd5f9b65d [InstCombine] Swap order of checks to improve compile time (NFC)
llvm-svn: 366962
2019-07-24 23:31:04 +00:00
Sanjay Patel 86e9f9dc26 [Transforms] move copying of load metadata to helper function; NFC
There's another proposed load combine that can make use of this code
in D64432.

llvm-svn: 366949
2019-07-24 22:11:11 +00:00
Petr Hosek 8b161bacf4 [SafeStack] Insert the deref before remaining elements
This is a follow up to D64971. While we need to insert the deref after
the offset, it needs to come before the remaining elements in the
original expression since the deref needs to happen before the LLVM
fragment if present.

Differential Revision: https://reviews.llvm.org/D65172

llvm-svn: 366865
2019-07-24 00:16:23 +00:00
Stefan Stipanovic 6058b86373 Fixing build error from commit 95cbc3d
[Attributor] Liveness analysis.

Liveness analysis abstract attribute used to indicate which BasicBlocks are dead and can therefore be ignored.
Right now we are only looking at noreturn calls.

Reviewers: jdoerfert, uenoku

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D64162

llvm-svn: 366769
2019-07-22 23:58:23 +00:00
Stefan Stipanovic 5a9ba27c71 Revert "Fixing build error from commit 9285295."
This reverts commit 95cbc3da88.

llvm-svn: 366759
2019-07-22 22:55:05 +00:00
Stefan Stipanovic 95cbc3da88 Fixing build error from commit 9285295.
[Attributor] Liveness analysis.

Liveness analysis abstract attribute used to indicate which BasicBlocks are dead and can therefore be ignored.
Right now we are only looking at noreturn calls.

Reviewers: jdoerfert, uenoku

Subscribers: hiraditya, llvm-commits

Differential revision: https://reviews.llvm.org/D64162

llvm-svn: 366753
2019-07-22 22:10:59 +00:00
Eric Christopher 77dc6d2479 Temporarily Revert "[Attributor] Liveness analysis." as it's breaking the build.
This reverts commit 9285295f75.

llvm-svn: 366737
2019-07-22 21:04:23 +00:00
Stefan Stipanovic 9285295f75 [Attributor] Liveness analysis.
Liveness analysis abstract attribute used to indicate which BasicBlocks are dead and can therefore be ignored.
Right now we are only looking at noreturn calls.

Reviewers: jdoerfert, uenoku

Subscribers: hiraditya, llvm-commits

Differential revision: https://reviews.llvm.org/D64162

llvm-svn: 366736
2019-07-22 20:54:30 +00:00
Petr Hosek f6cd6ffbc9 [SafeStack] Insert the deref after the offset
While debugging code that uses SafeStack, we've noticed that LLVM
produces an invalid DWARF. Concretely, in the following example:

  int main(int argc, char* argv[]) {
    std::string value = "";
    printf("%s\n", value.c_str());
    return 0;
  }

DWARF would describe the value variable as being located at:

  DW_OP_breg14 R14+0, DW_OP_deref, DW_OP_constu 0x20, DW_OP_minus

The assembly to get this variable is:

  leaq    -32(%r14), %rbx

The order of operations in the DWARF symbols is incorrect in this case.
Specifically, the deref is incorrect; this appears to be incorrectly
re-inserted in repalceOneDbgValueForAlloca.

With this change which inserts the deref after the offset instead of
before it, LLVM produces correct DWARF:

  DW_OP_breg14 R14-32

Differential Revision: https://reviews.llvm.org/D64971

llvm-svn: 366726
2019-07-22 18:52:42 +00:00
Serguei Katkov c6c31da867 [Loop Peeling] Fix the handling of branch weights of peeled off branches.
Current algorithm to update branch weights of latch block and its copies is
based on the assumption that number of peeling iterations is approximately equal
to trip count.

However it is not correct. According to profitability check in one case we can decide to peel
in case it helps to reduce the number of phi nodes. In this case the number of peeled iteration
can be less then estimated trip count.

This patch introduces another way to set the branch weights to peeled of branches.
Let F is a weight of the edge from latch to header.
Let E is a weight of the edge from latch to exit.
F/(F+E) is a probability to go to loop and E/(F+E) is a probability to go to exit.
Then, Estimated TripCount = F / E.
For I-th (counting from 0) peeled off iteration we set the the weights for
the peeled latch as (TC - I, 1). It gives us reasonable distribution,
The probability to go to exit 1/(TC-I) increases. At the same time
the estimated trip count of remaining loop reduces by I.

As a result after peeling off N iteration the weights will be
(F - N * E, E) and trip count of loop becomes
F / E - N or TC - N.

The idea is taken from the review of the patch D63918 proposed by Philip.

Reviewers: reames, mkuper, iajbar, fhahn
Reviewed By: reames
Subscribers: hiraditya, zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D64235

llvm-svn: 366665
2019-07-22 05:15:34 +00:00
Florian Hahn 0a7faa4e3d [Local] Zap blockaddress without users in ConstantFoldTerminator.
If the blockaddress is not destoryed, the destination block will still
be marked as having its address taken, limiting further transformations.

I think there are other places where the dead blockaddress constants are kept
around, I'll look into that as follow up.

Reviewers: craig.topper, brzycki, davide

Reviewed By: brzycki, davide

Differential Revision: https://reviews.llvm.org/D64936

llvm-svn: 366633
2019-07-20 12:25:47 +00:00
Serguei Katkov bde33af85a [Loop Peeling] Enable peeling of multiple exits by default.
Enable loop peeling with multiple exits where all non-latch exits
ends up with deopt by default.

Reviewers: reames, fhahn
Reviewed By: reames
Subscribers: xbolva00, hiraditya, zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D64619

llvm-svn: 366542
2019-07-19 08:35:45 +00:00
Serguei Katkov 0ffa833d54 [LoopInfo] Use early return in branch weight update functions. NFC.
llvm-svn: 366411
2019-07-18 07:36:20 +00:00
Rui Ueyama 49a3ad21d6 Fix parameter name comments using clang-tidy. NFC.
This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
2019-07-16 04:46:31 +00:00
Evgeniy Stepanov c5e7f56249 ARM MTE stack sanitizer.
Add "memtag" sanitizer that detects and mitigates stack memory issues
using armv8.5 Memory Tagging Extension.

It is similar in principle to HWASan, which is a software implementation
of the same idea, but there are enough differencies to warrant a new
sanitizer type IMHO. It is also expected to have very different
performance properties.

The new sanitizer does not have a runtime library (it may grow one
later, along with a "debugging" mode). Similar to SafeStack and
StackProtector, the instrumentation pass (in a follow up change) will be
inserted in all cases, but will only affect functions marked with the
new sanitize_memtag attribute.

Reviewers: pcc, hctim, vitalybuka, ostannard

Subscribers: srhines, mehdi_amini, javed.absar, kristof.beyls, hiraditya, cryptoad, steven_wu, dexonsmith, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D64169

llvm-svn: 366123
2019-07-15 20:02:23 +00:00
Serguei Katkov d021ad9fbe [Loop Peeling] Fix the bug with IDom setting for exit loops
It is possible that loop exit has two predecessors in a loop body.
In this case after the peeling the iDom of the exit should be a clone of
iDom of original exit but no a clone of a block coming to this exit.

Reviewers: reames, fhahn
Reviewed By: reames
Subscribers: hiraditya, zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D64618

llvm-svn: 366050
2019-07-15 09:13:11 +00:00
Serguei Katkov 3ed93b4673 [Loop Peeling] Enable peeling for loops with multiple exits
This CL enables peeling of the loop with multiple exits where
one exit should be from latch and others are basic blocks with
call to deopt.

The peeling is enabled under the flag which is false by default.

Reviewers: reames, mkuper, iajbar, fhahn
Reviewed By: reames
Subscribers: xbolva00, hiraditya, zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D63923

llvm-svn: 366048
2019-07-15 08:26:45 +00:00
Serguei Katkov 45c43e7d04 [LoopUtils] Extend the scope of getLoopEstimatedTripCount
With this patch the getLoopEstimatedTripCount function will
accept also the loops where there are more than one exit but
all exits except latch block should ends up with a call to deopt.

This side exits should not impact the estimated trip count.

Reviewers: reames, mkuper, danielcdh
Reviewed By: reames
Subscribers: fhahn, lebedev.ri, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D64553

llvm-svn: 366042
2019-07-15 06:42:39 +00:00
Serguei Katkov f1ee04c42a [LoopInfo] Introduce getUniqueNonLatchExitBlocks utility function
Extract the code from LoopUnrollRuntime into utility function to
re-use it in D63923.

Reviewers: reames, mkuper
Reviewed By: reames
Subscribers: fhahn, hiraditya, zzheng, dmgreen, llvm-commits
Differential Revision: https://reviews.llvm.org/D64548

llvm-svn: 366040
2019-07-15 05:51:10 +00:00
Alina Sbirlea db101864bd [MemorySSA] Use SetVector to avoid nondeterminism.
Summary:
Use a SetVector for DeadBlockSet.
Resolves PR42574.

Reviewers: george.burgess.iv, uabelho, dblaikie

Subscribers: jlebar, Prazek, mgrang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64601

llvm-svn: 365970
2019-07-12 22:30:30 +00:00
Fangrui Song b251cc0d91 Delete dead stores
llvm-svn: 365903
2019-07-12 14:58:15 +00:00
Evandro Menezes b21692672e [InstCombine] Reorder pow() transformations (NFC)
Move the transformation from `powf(x, itofp(y))` to `powi(x, y)` to the
group of transformations related to the exponent.

llvm-svn: 365851
2019-07-12 00:33:49 +00:00
Stefan Stipanovic 0626367202 [Attributor] Deduce "nosync" function attribute.
Introduce and deduce "nosync" function attribute to indicate that a function
does not synchronize with another thread in a way that other thread might free memory.

Reviewers: jdoerfert, jfb, nhaehnle, arsenm

Subscribers: wdng, hfinkel, nhaenhle, mehdi_amini, steven_wu,
dexonsmith, arsenm, uenoku, hiraditya, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D62766

llvm-svn: 365830
2019-07-11 21:37:40 +00:00
David Bolvansky e23be09e66 [InstCombine] Reorder recently added/improved pow transformations
Changed cases are now faster with exp2.

llvm-svn: 365758
2019-07-11 10:55:04 +00:00
Alina Sbirlea 58a37754bb [LoopRotate + MemorySSA] Keep an <instruction-cloned instruction> map.
Summary:
The map kept in loop rotate is used for instruction remapping, in order
to simplify the clones of instructions. Thus, if an instruction can be
simplified, its simplified value is placed in the map, even when the
clone is added to the IR. MemorySSA in contrast needs to know about that
clone, so it can add an access for it.
To resolve this: keep a different map for MemorySSA.

Reviewers: george.burgess.iv

Subscribers: jlebar, Prazek, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63680

llvm-svn: 365672
2019-07-10 17:36:56 +00:00
Vedant Kumar 5eb6ba060a [CodeExtractor] Fix sinking of allocas with multiple bitcast uses (PR42451)
An alloca which can be sunk into the extraction region may have more
than one bitcast use. Move these uses along with the alloca to prevent
use-before-def.

Testing: check-llvm, stage2 build of clang

Fixes llvm.org/PR42451.

Differential Revision: https://reviews.llvm.org/D64463

llvm-svn: 365660
2019-07-10 16:32:20 +00:00
Vedant Kumar f65f302cc7 [CodeExtractor] Simplify findAllocas, NFC
Split getLifetimeMarkers out into its own method and have it return a
struct.

Differential Revision: https://reviews.llvm.org/D64467

llvm-svn: 365659
2019-07-10 16:32:16 +00:00
David Bolvansky 0735cc1954 [InstCombine] pow(C,x) -> exp2(log2(C)*x)
Summary:
Transform
pow(C,x) 

To
exp2(log2(C)*x) 

if C > 0, C != inf, C != NaN (and C is not power of 2, since we have some fold for such case already).

log(C) is folded by the compiler and exp2 is much faster to compute than pow.

Reviewers: spatel, efriedma, evandro

Reviewed By: evandro

Subscribers: lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64099

llvm-svn: 365637
2019-07-10 14:43:27 +00:00
Serguei Katkov 77bb3a486f [Loop Peeling] Add support for peeling of loops with multiple exits
This patch modifies the loop peeling transformation so that
it does not expect that there is only one loop exit from latch.

It modifies only transformation. Update of branch weights remains
only for exit from latch.

The motivation is that in follow-up patch I plan to enable loop peeling for
loops with multiple exits but only if other exits then from latch one goes to
block with call to deopt.

For now this patch is NFC.

Reviewers: reames, mkuper, iajbar, fhahn	
Reviewed By: reames, fhahn
Subscribers: zzheng, llvm-commits
Differential Revision: https://reviews.llvm.org/D63921

llvm-svn: 365441
2019-07-09 06:07:25 +00:00
Whitney Tsang 7d8f30e6b2 Keep the order of the basic blocks in the cloned loop as the original
loop
Summary:
Do the cloning in two steps, first allocate all the new loops, then
clone the basic blocks in the same order as the original loop.
Reviewer: Meinersbur, fhahn, kbarton, hfinkel
Reviewed By: hfinkel
Subscribers: hfinkel, hiraditya, llvm-commits
Tag: https://reviews.llvm.org/D64224
Differential Revision:

llvm-svn: 365366
2019-07-08 18:30:35 +00:00
Brian Homerding b4b21d807e Add, and infer, a nofree function attribute
This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., free,
C++'s operator delete).

Reviewers: jdoerfert

Differential Revision: https://reviews.llvm.org/D49165

llvm-svn: 365336
2019-07-08 15:57:56 +00:00
Eugene Leviant 3aef35288b [ThinLTO] Attempt to recommit r365188 after alignment fix
llvm-svn: 365215
2019-07-05 15:25:05 +00:00
Eugene Leviant e91f86f0ac Reverted r365188 due to alignment problems on i686-android
llvm-svn: 365206
2019-07-05 13:26:05 +00:00
Eugene Leviant 820cc01d1e [ThinLTO] Attempt to recommit r365040 after caching fix
It's possible that some function can load and store the same
variable using the same constant expression:

store %Derived* @foo, %Derived** bitcast (%Base** @bar to %Derived**)
%42 = load %Derived*, %Derived** bitcast (%Base** @bar to %Derived**)

The bitcast expression was mistakenly cached while processing loads,
and never examined later when processing store. This caused @bar to
be mistakenly treated as read-only variable. See load-store-caching.ll.

llvm-svn: 365188
2019-07-05 12:00:10 +00:00
Serguei Katkov 6d8813a391 [LoopPeel] Some small comment update. NFC.
Follow-up change of comment after
https://reviews.llvm.org/D63917 is landed.

llvm-svn: 365107
2019-07-04 05:10:14 +00:00
Reid Kleckner f7e52fbdb5 Revert [ThinLTO] Optimize writeonly globals out
This reverts r365040 (git commit 5cacb91475)

Speculatively reverting, since this appears to have broken check-lld on
Linux. Partial analysis in https://crbug.com/981168.

llvm-svn: 365097
2019-07-04 00:03:30 +00:00
Eugene Leviant 5cacb91475 [ThinLTO] Optimize writeonly globals out
Differential revision: https://reviews.llvm.org/D63444

llvm-svn: 365040
2019-07-03 14:14:52 +00:00
Serguei Katkov c22e772a28 [LoopPeel] Re-factor llvm::peelLoop method. NFC.
Extract code dealing with branch weights in separate functions.

Reviewers: reames, mkuper, iajbar, fhahn
Reviewed By: reames, fhahn
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D63917

llvm-svn: 365002
2019-07-03 05:59:23 +00:00
David Bolvansky 10ee3ac396 [NFC] Strenghten isInteger condition for rL364940
llvm-svn: 364969
2019-07-02 21:16:34 +00:00
David Bolvansky cb1a5a705c [SimplifyLibCalls] powf(x, sitofp(n)) -> powi(x, n)
Summary:
Partially solves https://bugs.llvm.org/show_bug.cgi?id=42190



Reviewers: spatel, nikic, efriedma

Reviewed By: efriedma

Subscribers: efriedma, nikic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63038

llvm-svn: 364940
2019-07-02 15:58:45 +00:00
Reid Kleckner d72163947a [PGO] Update ICP pass for recent byval type changes
Fixes verifier errors encountered in PR42413.

Reviewers: xur, t.p.northover, inglorion, gbiv, george.burgess.iv

Differential Revision: https://reviews.llvm.org/D63842

llvm-svn: 364861
2019-07-01 22:43:39 +00:00
Sanjay Patel 77dc1e8568 [InstCombine] canonicalize fmin/fmax to LLVM intrinsics minnum/maxnum
This transform came up in D62414, but we should deal with it first.
We have LLVM intrinsics that correspond exactly to libm calls (unlike
most libm calls, these libm calls never set errno).
This holds without any fast-math-flags, so we should always canonicalize
to those intrinsics directly for better optimization.
Currently, we convert to fcmp+select only when we have FMF (nnan) because
fcmp+select does not preserve the semantics of the call in the general case.

Differential Revision: https://reviews.llvm.org/D63214

llvm-svn: 364714
2019-06-29 14:28:54 +00:00
Johannes Doerfert 3b77583e95 [Attr] Add "willreturn" function attribute
This patch introduces a new function attribute, willreturn, to indicate
that a call of this function will either exhibit undefined behavior or
comes back and continues execution at a point in the existing call stack
that includes the current invocation.

This attribute guarantees that the function does not have any endless
loops, endless recursion, or terminating functions like abort or exit.

Patch by Hideto Ueno (@uenoku)

Reviewers: jdoerfert

Subscribers: mehdi_amini, hiraditya, steven_wu, dexonsmith, lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62801

llvm-svn: 364555
2019-06-27 15:51:40 +00:00
Tim Northover 22c96a966b IR: compare type attributes deeply when looking into functions.
FunctionComparator attempts to produce a stable comparison of two Function
instances by looking at all available properties. Since ByVal attributes now
contain a Type pointer, they are not trivially ordered and FunctionComparator
should use its own Type comparison logic to sort them.

llvm-svn: 364523
2019-06-27 11:44:45 +00:00
Florian Hahn 4c11b5268c [LoopUnroll] Add support for loops with exiting headers and uncond latches.
This patch generalizes the UnrollLoop utility to support loops that exit
from the header instead of the latch. Usually, LoopRotate would take care
of must of those cases, but in some cases (e.g. -Oz), LoopRotate does
not kick in.

Codesize impact looks relatively neutral on ARM64 with -Oz + LTO.

Program                                         master     patch     diff
 External/S.../CFP2006/447.dealII/447.dealII   629060.00  627676.00  -0.2%
 External/SPEC/CINT2000/176.gcc/176.gcc        1245916.00 1244932.00 -0.1%
 MultiSourc...Prolangs-C/simulator/simulator   86100.00   86156.00    0.1%
 MultiSourc...arks/Rodinia/backprop/backprop   66212.00   66252.00    0.1%
 MultiSourc...chmarks/Prolangs-C++/life/life   67276.00   67312.00    0.1%
 MultiSourc...s/Prolangs-C/compiler/compiler   69824.00   69788.00   -0.1%
 MultiSourc...Prolangs-C/assembler/assembler   86672.00   86696.00    0.0%

Reviewers: efriedma, vsk, paquette

Reviewed By: paquette

Differential Revision: https://reviews.llvm.org/D61962

llvm-svn: 364398
2019-06-26 09:16:57 +00:00
Whitney Tsang 7c1deeff4a Expand cloneLoopWithPreheader() to support cloning loop nest
Summary: cloneLoopWithPreheader() currently only support innermost loop,
and assert otherwise.
Reviewers: Meinersbur, fhahn, kbarton
Reviewed By: Meinersbur
Subscribers: hiraditya, jsji, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D63446

llvm-svn: 364310
2019-06-25 13:23:13 +00:00
Orlando Cazalet-Hyams 1251cac62a [DebugInfo@O2][LoopVectorize] pr39024: Vectorized code linenos step through loop even after completion
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024

The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:

A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.

In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.

I have set up a separate review D61933 for a fix which is required for this patch.

Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse

Reviewed By: hfinkel, jmorse

Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D60831

> llvm-svn: 363046

llvm-svn: 363786
2019-06-19 10:50:47 +00:00
Yevgeny Rouban 69daf4a72d [SimplifyCFG] NFC, prof branch_weighs handling is simplified
Using the new SwitchInstProfUpdateWrapper this patch
simplifies 3 places of prof branch_weights handling.

Differential Revision: https://reviews.llvm.org/D62123

llvm-svn: 363652
2019-06-18 06:50:52 +00:00
Whitney Tsang 15b7f5b72d PHINode: introduce setIncomingValueForBlock() function, and use it.
Summary:
There is PHINode::getBasicBlockIndex() and PHINode::setIncomingValue()
but no function to replace incoming value for a specified BasicBlock*
predecessor.
Clearly, there are a lot of places that could use that functionality.

Reviewer: craig.topper, lebedev.ri, Meinersbur, kbarton, fhahn
Reviewed By: Meinersbur, fhahn
Subscribers: fhahn, hiraditya, zzheng, jsji, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D63338

llvm-svn: 363566
2019-06-17 14:38:56 +00:00
Hans Wennborg a9e5d2f35d Re-commit r357452 (take 3): "SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)"
Third time's the charm.

This was reverted in r363220 due to being suspected of an internal benchmark
regression and a test failure, none of which turned out to be caused by this.

llvm-svn: 363529
2019-06-17 07:47:28 +00:00
Yevgeny Rouban ee62c40eae [SimplifyCFG] Fix prof branch_weights MD while removing unreachable switch cases
SimplifyCFG has a bug that results in inconsistent prof branch_weights metadata
if unreachable switch cases are removed. This patch fixes this bug by making use
of the newly introduced SwitchInstProfUpdateWrapper class (see patch D62122).
A new test is created.

Differential Revision: https://reviews.llvm.org/D62186

llvm-svn: 363527
2019-06-17 05:55:12 +00:00
Nikita Popov 9145562b48 [SimplifyIndVar] Simplify non-overflowing saturating add/sub
If we can detect that saturating math that depends on an IV cannot
overflow, replace it with simple math. This is similar to the CVP
optimization from D62703, just based on a different underlying
analysis (SCEV vs LVI) that catches different cases.

Differential Revision: https://reviews.llvm.org/D62792

llvm-svn: 363489
2019-06-15 08:48:52 +00:00
Shawn Landden f2e60fc4e8 [SimpligyCFG] NFC intended, remove GCD that was only used for powers of two
and replace with an equilivent countTrailingZeros.

GCD is much more expensive than this, with repeated division.

This depends on D60823

Differential Revision: https://reviews.llvm.org/D61151

llvm-svn: 363422
2019-06-14 16:56:49 +00:00
Shawn Landden 8b142bcc3f [SimplifyCFG] reverting preliminary Switch patches again
This reverts 363226 and 363227, both NFC intended

I swear I fixed the test case that is failing, and ran
the tests, but I will look into it again.

llvm-svn: 363229
2019-06-13 05:26:17 +00:00
Shawn Landden 636220e83c [SimpligyCFG] NFC intended, remove GCD that was only used for powers of two
and replace with an equilivent countTrailingZeros.

GCD is much more expensive than this, with repeated division.

This depends on D60823

Differential Revision: https://reviews.llvm.org/D61151

llvm-svn: 363227
2019-06-13 05:01:44 +00:00
David L. Jones c73fadaa84 Revert r361811: 'Re-commit r357452 (take 2): "SimplifyCFG SinkCommonCodeFromPredecessors ...'
We have observed some failures with internal builds with this revision.

- Performance regressions:
  - llvm's SingleSource/Misc evalloop shows performance regressions (although these may be red herrings).
  - Benchmarks for Abseil's SwissTable.
- Correctness:
  - Failures for particular libicu tests when building the Google AppEngine SDK (for PHP).

hwennborg has already been notified, and is aware of reproducer failures.

llvm-svn: 363220
2019-06-13 02:04:45 +00:00
Matt Arsenault aa6bdf9dcd LoopVersioning: Respect convergent
This changes the standalone pass only. Arguably the utility class
itself should assert there are no convergent calls. However, a target
pass with additional context may still be able to version a loop if
all of the dynamic conditions are sufficiently uniform.

llvm-svn: 363165
2019-06-12 14:05:58 +00:00
Orlando Cazalet-Hyams a947156396 Revert "[DebugInfo@O2][LoopVectorize] pr39024: Vectorized code linenos step through loop even after completion"
This reverts commit 1a0f7a2077.
See phabricator thread for D60831.

llvm-svn: 363132
2019-06-12 08:34:51 +00:00
Philip Reames 082cd30327 Generalize icmp matching in IndVars' eliminateTrunc
We were only matching RHS being a loop invariant value, not the inverse. Since there's nothing which appears to canonicalize loop invariant values to RHS, this means we missed cases.

Differential Revision: https://reviews.llvm.org/D63112

llvm-svn: 363108
2019-06-11 22:43:25 +00:00
Orlando Cazalet-Hyams 1a0f7a2077 [DebugInfo@O2][LoopVectorize] pr39024: Vectorized code linenos step through loop even after completion
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024

The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:

A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.

In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.

I have set up a separate review D61933 for a fix which is required for this patch.

Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel, jmorse

Reviewed By: hfinkel, jmorse

Subscribers: jmorse, javed.absar, eraman, kcc, bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D60831

llvm-svn: 363046
2019-06-11 10:37:20 +00:00
Sander de Smalen cbeb563cfb Change semantics of fadd/fmul vector reductions.
This patch changes how LLVM handles the accumulator/start value
in the reduction, by never ignoring it regardless of the presence of
fast-math flags on callsites. This change introduces the following
new intrinsics to replace the existing ones:

  llvm.experimental.vector.reduce.fadd -> llvm.experimental.vector.reduce.v2.fadd
  llvm.experimental.vector.reduce.fmul -> llvm.experimental.vector.reduce.v2.fmul

and adds functionality to auto-upgrade existing LLVM IR and bitcode.

Reviewers: RKSimon, greened, dmgreen, nikic, simoll, aemerson

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D60261

llvm-svn: 363035
2019-06-11 08:22:10 +00:00
Keno Fischer eb4a561fa3 [GVN] non-functional code movement
Summary: Move some code around, in preparation for later fixes
to the non-integral addrspace handling (D59661)

Patch By Jameson Nash <jameson@juliacomputing.com>

Reviewed By: reames, loladiro
Differential Revision: https://reviews.llvm.org/D59729

llvm-svn: 362853
2019-06-07 23:08:38 +00:00
Alina Sbirlea eaea538d18 [DomTreeUpdater] Add all insert before all delete updates to reduce compile time.
Summary:
The cleanup in D62751 introduced a compile-time regression due to the way DT updates are performed.
Add all insert edges then all delete edges in DTU to match the previous compile time.
Compile time on the test provided by @mstorsjo before and after this patch on my machine:
113.046s vs 35.649s
Repro: clang -target x86_64-w64-mingw32 -c -O3 glew-preproc.c; on https://martin.st/temp/glew-preproc.c.

Reviewers: kuhar, NutshellySima, mstorsjo

Subscribers: jlebar, mstorsjo, dmgreen, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62981

llvm-svn: 362839
2019-06-07 20:43:55 +00:00
Mircea Trofin e3eeacd70a [CallSite removal] Refactoring llvm::InlineFunction APIs
Summary:
This change only unifies the API previous API pair accepting
CallInst and InvokeInst, thus making it easier to refactor
inliner pass ode to CallBase. The implementation of the unified
API still relies on the CallSite implementation.

Reviewers: eraman, chandlerc, jdoerfert

Reviewed By: jdoerfert

Subscribers: jdoerfert, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62283

llvm-svn: 362656
2019-06-05 21:28:13 +00:00
Sanjay Patel ad62a3a299 [LoopUtils][SLPVectorizer] clean up management of fast-math-flags
Instead of passing around fast-math-flags as a parameter, we can set those
using an IRBuilder guard object. This is no-functional-change-intended.

The motivation is to eventually fix the vectorizers to use and set the
correct fast-math-flags for reductions. Examples of that not behaving as
expected are:
https://bugs.llvm.org/show_bug.cgi?id=23116 (should be able to reduce with less than 'fast')
https://bugs.llvm.org/show_bug.cgi?id=35538 (possible miscompile for -0.0)
D61802 (should be able to reduce with IR-level FMF)

Differential Revision: https://reviews.llvm.org/D62272

llvm-svn: 362612
2019-06-05 14:58:04 +00:00
Alina Sbirlea bfceed49ce [Utils] Clean another duplicated util method.
Summary:
Following the cleanup in D48202, method foldBlockIntoPredecessor has the
same behavior. Replace its uses with MergeBlockIntoPredecessor.
Remove foldBlockIntoPredecessor.

Reviewers: chandlerc, dmgreen

Subscribers: jlebar, javed.absar, zzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62751

llvm-svn: 362538
2019-06-04 18:45:15 +00:00
Andrew Kaylor 4172dbab5d Fix a crash when the default of a switch is removed
This patch fixes a problem that occurs in LowerSwitch when a switch statement has a PHI node as its condition, and the PHI node only has two incoming blocks, and one of those incoming blocks is through an unreachable default in the switch statement. When this condition occurs, LowerSwitch holds a pointer to the condition value, but removes the switch block as a predecessor of the PHI block, causing the PHI node to be replaced. LowerSwitch then tries to use its stale pointer to the original condition value, causing a crash.

Differential Revision: https://reviews.llvm.org/D62560

llvm-svn: 362427
2019-06-03 17:54:15 +00:00
Nikita Popov 900578d1c1 [SimplifyIndVar] Refactor overflow check elimination code; NFC
Extract a willNotOverflow() helper function that is shared between
eliminateOverflowIntrinsic() and strengthenOverflowingOperation().
Use WithOverflowInst for the former.

We'll be able to reuse the same code for saturating intrinsics as
well.

llvm-svn: 362305
2019-06-01 20:21:53 +00:00
Erik Pilkington abb2a93c53 [SimplifyLibCalls] Fold more fortified functions into non-fortified variants
When the object size argument is -1, no checking can be done, so calling the
_chk variant is unnecessary. We already did this for a bunch of these
functions.

rdar://50797197

Differential revision: https://reviews.llvm.org/D62358

llvm-svn: 362272
2019-05-31 22:41:36 +00:00
Erik Pilkington 5234921119 NFC: Pull out a function to reduce some duplication
Part of https://reviews.llvm.org/D62358

llvm-svn: 362271
2019-05-31 22:41:31 +00:00
Tim Northover b7141207a4 Reapply: IR: add optional type to 'byval' function parameters
When we switch to opaque pointer types we will need some way to describe
how many bytes a 'byval' parameter should occupy on the stack. This adds
a (for now) optional extra type parameter.

If present, the type must match the pointee type of the argument.

The original commit did not remap byval types when linking modules, which broke
LTO. This version fixes that.

Note to front-end maintainers: if this causes test failures, it's probably
because the "byval" attribute is printed after attributes without any parameter
after this change.

llvm-svn: 362128
2019-05-30 18:48:23 +00:00
Hans Wennborg d936e40575 Re-commit r357452 (take 2): "SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)"
This was reverted in r360086 as it was supected of causing mysterious test
failures internally. However, it was never concluded that this patch was the
root cause.

> The code was previously checking that candidates for sinking had exactly
> one use or were a store instruction (which can't have uses). This meant
> we could sink call instructions only if they had a use.
>
> That limitation seemed a bit arbitrary, so this patch changes it to
> "instruction has zero or one use" which seems more natural and removes
> the need to special-case stores.
>
> Differential revision: https://reviews.llvm.org/D59936

llvm-svn: 361811
2019-05-28 12:19:38 +00:00
Shawn Landden 343578759e [SimplifyCFG] back out all SwitchInst commits
They caused the sanitizer builds to fail.

My suspicion is the change the countLeadingZeros().

llvm-svn: 361736
2019-05-26 18:15:51 +00:00
Shawn Landden fa91ab85d9 [SimplifyCFG] ReduceSwitchRange: Improve on the case where the SubThreshold doesn't trigger
llvm-svn: 361728
2019-05-26 13:55:52 +00:00
Shawn Landden 30111c786f [SimplifyCFG] Run ReduceSwitchRange unconditionally, generalize
Rather than gating on "isSwitchDense" (resulting in necessesarily
sparse lookup tables even when they were generated), always run
this quite cheap transform.

This transform is useful not just for generating tables.
LowerSwitch also wants this: read LowerSwitch.cpp:257.

Be careful to not generate worse code, by introducing a
SubThreshold heuristic.

Instead of just sorting by signed, generalize the finding of the
best base.

And now that it is run unconditionally, do not replicate its
functionality in SwitchToLookupTable (which could use a Sub
when having a hole is smaller, hence the SubThreshold
heuristic located in a single place).
This simplifies SwitchToLookupTable, and fixes
some ugly corner cases due to the use of signed numbers,
such as a table containing i16 32768 and 32769, of which
32769 would be interpreted as -32768, and now the code thinks
the table is size 65536.

(We still use unconditional subtraction when building a single-register mask,
but I think this whole block should go when the more general sparse
map is added, which doesn't leave empty holes in the table.)

And the reason test4 and test5 did not trigger was documented wrong:
it was because they were not considered sufficiently "dense".

Also, fix generation of invalid LLVM-IR: shl by bit-width.

llvm-svn: 361727
2019-05-26 13:55:14 +00:00
Shawn Landden 444eaaf1cc [SimpligyCFG] NFC, remove GCD that was only used for powers of two
and replace with an equilivent countTrailingZeros.

GCD is much more expensive than this, with repeated division.

This depends on D60823

llvm-svn: 361726
2019-05-26 13:54:04 +00:00
Shawn Landden b7cc093db2 [Support] make countLeadingZeros() and countTrailingZeros() return unsigned
This matches countLeadingOnes() and countTrailingOnes(), and
APInt's countLeadingZeros() and countTrailingZeros().

(as well as __builtin_clzll())

llvm-svn: 361724
2019-05-26 13:49:58 +00:00
David Bolvansky 0290a77aa8 [SimplifyCFG] Added condition assumption for unreachable blocks
Summary: PR41688

Reviewers: spatel, efriedma, craig.topper, hfinkel, reames

Reviewed By: hfinkel

Subscribers: javed.absar, dmgreen, fhahn, hfinkel, reames, nikic, lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61409

llvm-svn: 361707
2019-05-25 22:34:27 +00:00
Bob Haarman 032f87bbb3 Revert r360902 "Resubmit: [Salvage] Change salvage debug info ..."
This reverts commit rr360902. It caused an assertion failure in
lib/IR/DebugInfoMetadata.cpp: Assertion `(OffsetInBits + SizeInBits <=
FragmentSizeInBits) && "new fragment outside of original fragment"'
failed.

PR41931.

llvm-svn: 361246
2019-05-21 11:53:41 +00:00
Orlando Cazalet-Hyams ed67bf8d2f Resubmit "[DebugInfo] Update loop metadata for inlined loops"
This reverts commit 95805bc425.
I've squashed the test fix into this commit.

[DebugInfo] Update loop metadata for inlined loops

Currently, when a loop is cloned while inlining function (A) into function (B)
the loop metadata is copied and then not modified at all. The loop metadata can
encode the loop's start and end DILocations. Therefore, the new inlined loop in
function (B) may have loop metadata which shows start and end locations residing
in function (A).

This patch ensures loop metadata is updated while inlining so that the start and
end DILocations are given the "inlinedAt" operand. I've also added a regression
test for this.

This fix is required for D60831 because that patch uses loop metadata to
determine the DILocation for the branches of new loop preheaders.

Reviewers: aprantl, dblaikie, anemet

Reviewed By: aprantl

Subscribers: eraman, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D61933

llvm-svn: 361149
2019-05-20 13:02:30 +00:00
Orlando Cazalet-Hyams 95805bc425 Revert "[DebugInfo] Update loop metadata for inlined loops"
This reverts commit 6e8f1a80cd.
Reverting patch while investigating build bot failure.

llvm-svn: 361143
2019-05-20 11:24:39 +00:00
Petar Jovanovic e85bbf564d [DebugInfoMetadata] Refactor DIExpression::prepend constants (NFC)
Refactor DIExpression::With* into a flag enum in order to be less
error-prone to use (as discussed on D60866).

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D61943

llvm-svn: 361137
2019-05-20 10:35:57 +00:00
Orlando Cazalet-Hyams 6e8f1a80cd [DebugInfo] Update loop metadata for inlined loops
Summary:
Currently, when a loop is cloned while inlining function (A) into function (B) the loop metadata is copied and then not modified at all. The loop metadata can encode the loop's start and end DILocations. Therefore, the new inlined loop in function (B) may have loop metadata which shows start and end locations residing in function (A).

This patch ensures loop metadata is updated while inlining so that the start and end DILocations are given the "inlinedAt" operand. I've also added a regression test for this.

This fix is required for D60831 because that patch uses loop metadata to determine the DILocation for the branches of new loop preheaders.

Reviewers: aprantl, dblaikie, anemet

Reviewed By: aprantl

Subscribers: eraman, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D61933

llvm-svn: 361132
2019-05-20 09:40:44 +00:00
Stephen Tozer 6f59b4b6d9 Resubmit: [Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645

Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop casts
impossible. With the recent addition of DW_OP_LLVM_convert this salvaging is
now possible, and so can be used to fix the attached bug as well as any cases
where SExt instruction results are lost in the debugging metadata. This patch
introduces this fix by expanding the salvage debug info method to cover these
cases using the new operator.

Differential revision: https://reviews.llvm.org/D61184

llvm-svn: 360902
2019-05-16 14:41:01 +00:00
Taewook Oh 9d020de3e8 [PredicateInfo] Do not process unreachable operands.
Summary: We should excluded unreachable operands from processing as their DFS visitation order is undefined. When `renameUses` function sorts `OpsToRename` (https://fburl.com/d2wubn60), the comparator assumes that the parent block of the operand has a corresponding dominator tree node. This is not the case for unreachable operands and crashes the compiler.

Reviewers: dberlin, mgrang, davide

Subscribers: efriedma, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61154

llvm-svn: 360796
2019-05-15 19:35:38 +00:00
Stephen Tozer 0d02f2ff4f Revert "[Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed"
This reverts r360772 due to build issues.
Reverted commit: 17dd4d7403.

llvm-svn: 360773
2019-05-15 13:41:44 +00:00
Stephen Tozer 17dd4d7403 [Salvage] Change salvage debug info implementation to use DW_OP_LLVM_convert where needed
Fixes issue: https://bugs.llvm.org/show_bug.cgi?id=40645

Previously, LLVM had no functional way of performing casts inside of a
DIExpression(), which made salvaging cast instructions other than Noop
casts impossible. With the recent addition of DW_OP_LLVM_convert this
salvaging is now possible, and so can be used to fix the attached bug as
well as any cases where SExt instruction results are lost in the
debugging metadata. This patch introduces this fix by expanding the
salvage debug info method to cover these cases using the new operator.

Differential revision: https://reviews.llvm.org/D61184

llvm-svn: 360772
2019-05-15 13:15:48 +00:00
Fangrui Song f4dfd63c74 [IR] Disallow llvm.global_ctors and llvm.global_dtors of the 2-field form in textual format
The 3-field form was introduced by D3499 in 2014 and the legacy 2-field
form was planned to be removed in LLVM 4.0

For the textual format, this patch migrates the existing 2-field form to
use the 3-field form and deletes the compatibility code.
test/Verifier/global-ctors-2.ll checks we have a friendly error message.

For bitcode, lib/IR/AutoUpgrade UpgradeGlobalVariables will upgrade the
2-field form (add i8* null as the third field).

Reviewed By: rnk, dexonsmith

Differential Revision: https://reviews.llvm.org/D61547

llvm-svn: 360742
2019-05-15 02:35:32 +00:00
Alina Sbirlea 80c6e79602 [MemorySSA] LoopSimplify preserves MemorySSA only when flag is flipped.
LoopSimplify can preserve MemorySSA after r360270.
But the MemorySSA analysis is retrieved and preserved only when the
EnableMSSALoopDependency is set to true. Use the same conditional to
mark the pass as preserved, otherwise subsequent passes will get an
invalid analysis.
Resolves PR41853.

llvm-svn: 360697
2019-05-14 18:07:18 +00:00
Jeremy Morse a2b780b731 [DebugInfo] Use zero linenos for debug intrinsics when promoting dbg.declare
In certain circumstances, optimizations pick line numbers from debug
intrinsic instructions as the new location for altered instructions. This
is problematic because the line number of a debugging intrinsic is
meaningless (it doesn't produce any machine instruction), only the scope
information is valid. The result can be the line number of a variable
declaration "leaking" into real code from debugging intrinsics, making the
line table un-necessarily jumpy, and potentially different with / without
variable locations.

Fix this by using zero line numbers when promoting dbg.declare intrinsics
into dbg.values: this is safe for debug intrinsics as their line numbers
are meaningless, and reduces the scope for damage / misleading stepping
when optimizations pick locations from the wrong place.

Differential Revision: https://reviews.llvm.org/D59272

llvm-svn: 360415
2019-05-10 10:03:41 +00:00
David Stuttard 411488b11e [CodeGenPrepare] Limit recursion depth for collectBitParts
Summary:
Seeing some issues for windows debug pathological cases with collectBitParts
recursion (1525 levels of recursion!)
Setting the limit to 64 as this should be sufficient - passes all lit cases

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61728

Change-Id: I7f44cdc6c1badf1c2ccbf1b0c4b6afe27ecb39a1
llvm-svn: 360347
2019-05-09 15:02:10 +00:00
Alina Sbirlea f31eba6494 [MemorySSA] Teach LoopSimplify to preserve MemorySSA.
Summary:
Preserve MemorySSA in LoopSimplify, in the old pass manager, if the analysis is available.
Do not preserve it in the new pass manager.
Update tests.

Subscribers: nemanjai, jlebar, javed.absar, Prazek, kbarton, zzheng, jsji, llvm-commits, george.burgess.iv, chandlerc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60833

llvm-svn: 360270
2019-05-08 17:05:36 +00:00
Kostya Serebryany b9c5768302 revert r360162 as it breaks most of the buildbots
llvm-svn: 360190
2019-05-07 20:57:11 +00:00
Orlando Cazalet-Hyams 78a6062c24 [DebugInfo@O2][LoopVectorize] pr39024: Vectorized code linenos step through loop even after completion
Summary:
Bug: https://bugs.llvm.org/show_bug.cgi?id=39024

The bug reports that a vectorized loop is stepped through 4 times and each step through the loop seemed to show a different path. I found two problems here:

A) An incorrect line number on a preheader block (for.body.preheader) instruction causes a step into the loop before it begins.
B) Instructions in the middle block have different line numbers which give the impression of another iteration.

In this patch I give all of the middle block instructions the line number of the scalar loop latch terminator branch. This seems to provide the smoothest debugging experience because the vectorized loops will always end on this line before dropping into the scalar loop. To solve problem A I have altered llvm::SplitBlockPredecessors to accommodate loop header blocks.

Reviewers: samsonov, vsk, aprantl, probinson, anemet, hfinkel

Reviewed By: hfinkel

Subscribers: bjope, jmellorcrummey, hfinkel, gbedwell, hiraditya, zzheng, llvm-commits

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D60831

llvm-svn: 360162
2019-05-07 15:37:38 +00:00
Orlando Cazalet-Hyams 0d05177337 Test commit access
llvm-svn: 360125
2019-05-07 09:30:55 +00:00
Jordan Rupprecht 8f14e7cacf Revert "Re-commit r357452: SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)"
This reverts r357452 (git commit 21eb771dcb).

This was causing strange optimization-related test failures on an internal test. Will followup with more details offline.

llvm-svn: 360086
2019-05-06 21:55:05 +00:00
Simon Pilgrim 364ef5db2b Pull out repeated CI->getCalledFunction() calls. NFCI.
llvm-svn: 360070
2019-05-06 19:51:54 +00:00
Clement Courbet 9e1f2a7fe7 [SimplifyLibCalls] Simplify bcmp too.
Summary: Fixes PR40699.

Reviewers: gchatelet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61585

llvm-svn: 360021
2019-05-06 09:15:22 +00:00
Roman Lebedev 7ad5d14f3a [NFC] Instruction: introduce replaceSuccessorWith() function, use it
Summary:
There is `Instruction::getNumSuccessors()`, `Instruction::getSuccessor()`
and `Instruction::setSuccessor()`, but no function to replace every
specified `BasicBlock*` successor with some other specified `BasicBlock*`.
I've found one place where it should clearly be used.

Reviewers: chandlerc, craig.topper, spatel, danielcdh

Reviewed By: craig.topper

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61010

llvm-svn: 359994
2019-05-05 18:59:22 +00:00
Roman Lebedev e5be660e25 [NFC][Utils] deleteDeadLoop(): add an assert that exit block has some non-PHI instruction
Summary:
If `deleteDeadLoop()` is called on such a loop, that has "bad" exit block,
one that e.g. has no terminator instruction, the `DIBuilder::insertDbgValueIntrinsic()`
will be told to insert the Dbg Value Intrinsic after `nullptr`
(since there is no first non-PHI instruction), which will cause it to not insert
those instructions into any basic block. The instructions will be parent-less,
and IR verifier will complain. It is rather obvious to track down the root cause
when that happens, so let's just assert it never happens.

Reviewers: sanjoy, davide, vsk

Reviewed By: vsk

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61008

llvm-svn: 359993
2019-05-05 18:59:12 +00:00
Evandro Menezes ea349f3ef5 [SimplifyLibCalls] Clean up code (NFC)
Fix pointer check after dereferencing (PR41665).

llvm-svn: 359595
2019-04-30 18:35:38 +00:00
Robert Lougher d469133f95 [Evaluator] Walk initial elements when handling load through bitcast
When evaluating a store through a bitcast, the evaluator tries to move the
bitcast from the pointer onto the stored value. If the cast is invalid, it
tries to "introspect" the type to get a valid cast by obtaining a pointer to
the initial element (if the type is nested, this may require walking several
initial elements).

In some situations it is possible to get a bitcast on a load (e.g. with
unions, where the bitcast may not be the same type as the store). However,
equivalent logic to the store to introspect the type is missing. This patch
add this logic.

Note, when developing the patch I was unhappy with adding similar logic
directly to the load case as it could get out of step. Instead, I have
abstracted the "introspection" into a helper function, with the specifics
being handled by a passed-in lambda function.

Differential Revision: https://reviews.llvm.org/D60793

llvm-svn: 359205
2019-04-25 17:00:01 +00:00
Bjorn Pettersson 71e8c6f20f Add "const" in GetUnderlyingObjects. NFC
Summary:
Both the input Value pointer and the returned Value
pointers in GetUnderlyingObjects are now declared as
const.

It turned out that all current (in-tree) uses of
GetUnderlyingObjects were trivial to update, being
satisfied with have those Value pointers declared
as const. Actually, in the past several of the users
had to use const_cast, just because of ValueTracking
not providing a version of GetUnderlyingObjects with
"const" Value pointers. With this patch we get rid
of those const casts.

Reviewers: hfinkel, materi, jkorous

Reviewed By: jkorous

Subscribers: dexonsmith, jkorous, jholewinski, sdardis, eraman, hiraditya, jrtc27, atanasyan, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61038

llvm-svn: 359072
2019-04-24 06:55:50 +00:00
Alina Sbirlea 4fd1f266b1 [MemorySSA] LCSSA preserves MemorySSA.
Summary:
Enabling MemorySSA in the old pass manager leads to MemorySSA being run
twice due to the fact that LCSSA and LoopSimplify do not preserve
MemorySSA. This is the first step to address that: target LCSSA.

LCSSA does not make any changes that invalidate MemorySSA, so it
preserves it by design. It must preserve AA as well, for this to hold.

After this patch, MemorySSA is still run twice in the old pass manager.
Step two follows: target LoopSimplify.

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60832

llvm-svn: 359032
2019-04-23 20:59:44 +00:00
Fangrui Song efd94c56ba Use llvm::stable_sort
While touching the code, simplify if feasible.

llvm-svn: 358996
2019-04-23 14:51:27 +00:00
Philip Reames 37104d7189 [LPM/BPI] Preserve BPI through trivial loop pass pipeline (e.g. LCSSA, LoopSimplify)
Currently, we do not expose BPI to loop passes at all. In the old pass manager, we appear to have been ignoring the fact that LCSSA and/or LoopSimplify didn't preserve BPI, and making it available to the following loop passes anyways.  In the new one, it's invalidated before running any loop pass if either LCSSA or LoopSimplify actually make changes. If they don't make changes, then BPI is valid and available.  So, we go ahead and teach LCSSA and LoopSimplify how to preserve BPI for consistency between old and new pass managers.

This patch avoids an invalidation between the two requires in the following trivial pass pipeline:
opt -passes="requires<branch-prob>,loop(no-op-loop),requires<branch-prob>"
(when the input file is one which requires either LCSSA or LoopSimplify to canonicalize the loops)

Differential Revision: https://reviews.llvm.org/D60790

llvm-svn: 358901
2019-04-22 17:13:43 +00:00