Commit Graph

6844 Commits

Author SHA1 Message Date
Chandler Carruth 86f0bdf832 [LCG] Minor cleanup to the LCG walk over a function, NFC.
This just hoists the check for declarations up a layer which allows
various sets used in the walk to be smaller. Also moves the relevant
comments to match, and catches a few other cleanups in this code.

llvm-svn: 289163
2016-12-09 00:46:44 +00:00
Zia Ansari 394cef803a [InstSimplify] Add "X / 1.0" to SimplifyFDivInst.
Differential Revision: https://reviews.llvm.org/D27587

llvm-svn: 289153
2016-12-08 23:27:40 +00:00
Peter Collingbourne 235c275b20 IR, X86: Understand !absolute_symbol metadata on global variables.
Summary:
Attaching !absolute_symbol to a global variable does two things:
1) Marks it as an absolute symbol reference.
2) Specifies the value range of that symbol's address.
Teach the X86 backend to allow absolute symbols to appear in place of
immediates by extending the relocImm and mov64imm32 matchers. Start using
relocImm in more places where it is legal.

As previously proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105800.html

Differential Revision: https://reviews.llvm.org/D25878

llvm-svn: 289087
2016-12-08 19:01:00 +00:00
Keno Fischer dc09119776 ConstantFolding: Don't crash when encountering vector GEP
ConstantFolding tried to cast one of the scalar indices to a vector
type. Instead, use the vector type only for the first index (which
is the only one allowed to be a vector) and use its scalar type
otherwise.

Fixes PR31250.

Reviewers: majnemer
Differential Revision: https://reviews.llvm.org/D27389

llvm-svn: 289073
2016-12-08 17:22:35 +00:00
Matt Arsenault 624e1b348c InstCombine: Fold bitcast of vector to FP scalar
llvm-svn: 288978
2016-12-07 20:56:11 +00:00
Philip Reames 02bb6a6b0b Reintroduce a check accidentally removed in 288873 to fix clang bots
I believe this is the cause of the failure, but have not been able to confirm.  Note that this is a speculative fix; I'm still waiting for a full build to finish as I synced and ended up doing a clean build which takes 20+ minutes on my machine.

llvm-svn: 288886
2016-12-07 04:48:50 +00:00
Philip Reames 29b19f0e9e Fix a warning introduced in r288874
llvm-svn: 288884
2016-12-07 04:11:22 +00:00
Chandler Carruth 5205c35075 [LCG] Add basic verification of the parent set and fix bugs it uncovers.
The existing unittests actually cover this now that we verify things.

llvm-svn: 288875
2016-12-07 01:42:40 +00:00
Philip Reames 71a496777c [LVI] Remove used return value from markX functions
llvm-svn: 288874
2016-12-07 01:03:56 +00:00
Philip Reames b47a719ac0 [LVI] Simplify mergeIn code
Remove the unused return type, use early return, use assignment operator.

llvm-svn: 288873
2016-12-07 00:54:21 +00:00
Philip Reames 864ab5c516 [LVI] Simplify obfuscated code
It doesn't matter why something is overdefined if it is...

llvm-svn: 288871
2016-12-07 00:28:28 +00:00
Sanjay Patel 5369775a84 [InstSimplify] fixed (?) to not mutate icmps
As Eli noted in the post-commit thread for r288833, the use of
swapOperands() may not be allowed in InstSimplify, so I'm 
removing those calls here pending further review. 

The swap mutates the icmp, and there doesn't appear to be precedent
for instruction mutation in InstSimplify.

I didn't actually have any tests for those cases, so I'm adding
a few here. 

llvm-svn: 288855
2016-12-06 22:09:52 +00:00
Sanjay Patel 9b1b2de348 [InstSimplify] add folds for and-of-icmps with same operands
All of these (and a few more) are already handled by InstCombine,
but we shouldn't have to wait until then to simplify these because
they're cheap to deal with here in InstSimplify.

This is the 'and' sibling of the earlier 'or' patch:
https://reviews.llvm.org/rL288833

llvm-svn: 288841
2016-12-06 19:05:46 +00:00
Sanjay Patel d0ccdb46b9 [InstSimplify] add folds for or-of-icmps with same operands
All of these (and a few more) are already handled by InstCombine,
but we shouldn't have to wait until then to simplify these because
they're cheap to deal with here in InstSimplify.

llvm-svn: 288833
2016-12-06 18:09:37 +00:00
Chandler Carruth 23a6c3f746 [LCG] Add some much needed asserts and verify runs to uncover
a hilarious bug and fix it.

We somehow were never verifying the RefSCCs newly formed when
splitting an existing one apart, and when verifying them we weren't
really checking the SCC indices mapping effectively.

If we had been, it would have been blindingly obvious that right after
putting something int `RC.SCCs` we should update `RC.SCCIndices` instead
of `SCCIndices` which we were about to clear and rebuild anyways. =[

Anyways, this is thoroughly covered by existing tests now that we
actually verify things properly.

llvm-svn: 288795
2016-12-06 10:29:23 +00:00
Chandler Carruth 8977223e55 [PM] Basic cleanups to CGSCC update code, NFC.
Just using InstIterator, simpler loop structures, and making better use
of the visit callback infrastructure.

llvm-svn: 288790
2016-12-06 10:06:06 +00:00
Philip Reames b486c49ff5 [LVI] Remove dead code in mergeIn
Integers are expressed in the lattice via constant ranges.  They can never be represented by constants or not-constants; those are reserved for non-integer types.  This code has been dead for literaly years.

llvm-svn: 288767
2016-12-06 03:34:33 +00:00
Philip Reames 05c435e3a4 [LVI] Extract a helper function
Extracting a helper function out of solveBlockValue makes the contract around the cache much easier to understand.

llvm-svn: 288766
2016-12-06 03:22:03 +00:00
Philip Reames 1baaef138d [LVI] Hide the last markX function on LVILatticeVal
This completes a small series of patches to hide the stateful updates of LVILatticeVal from the consuming code.  The only remaining stateful API is mergeIn.

llvm-svn: 288765
2016-12-06 03:01:08 +00:00
Philip Reames b29496246f [LVI] Hide a confusing internal interface
llvm-svn: 288764
2016-12-06 02:54:16 +00:00
Philip Reames 0e613f7c65 [LVI] Remove duplicate code using existing helper function
llvm-svn: 288761
2016-12-06 02:36:58 +00:00
Keno Fischer 92f377bd74 [LAA] Prevent invalid IR for loop-invariant bound in loop body
Summary:
If LAA expands a bound that is loop invariant, but not hoisted out
of the loop body, it used to use that value anyway, causing a
non-domination error, because the memcheck block is of course not
dominated by the scalar loop body. Detect this situation and expand
the SCEV expression instead.

Fixes PR31251

Reviewers: anemet
Subscribers: mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D27397

llvm-svn: 288705
2016-12-05 21:25:03 +00:00
Sanjay Patel 9d5b5e38bb [InstSimplify] add more helper functions for SimplifyICmpInst; NFCI
llvm-svn: 288589
2016-12-03 18:03:53 +00:00
Sanjay Patel dc65a27a10 [InstSimplify] add helper functions for SimplifyICmpInst; NFCI
llvm-svn: 288588
2016-12-03 17:30:22 +00:00
Peter Collingbourne 4568158c4d IR: Change PointerType to derive from Type rather than SequentialType.
As proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/106640.html

This is for a couple of reasons:

- Values of type PointerType are unlike the other SequentialTypes (arrays
  and vectors) in that they do not hold values of the element type. By moving
  PointerType we can unify certain aspects of how the other SequentialTypes
  are handled.
- PointerType will have no place in the SequentialType hierarchy once
  pointee types are removed, so this is a necessary step towards removing
  pointee types.

Differential Revision: https://reviews.llvm.org/D26595

llvm-svn: 288462
2016-12-02 03:05:41 +00:00
Matt Arsenault 47a4b39646 ConstantFolding: Factor code into helper function
llvm-svn: 288459
2016-12-02 02:26:02 +00:00
Peter Collingbourne ab85225be4 IR: Change the gep_type_iterator API to avoid always exposing the "current" type.
Instead, expose whether the current type is an array or a struct, if an array
what the upper bound is, and if a struct the struct type itself. This is
in preparation for a later change which will make PointerType derive from
Type rather than SequentialType.

Differential Revision: https://reviews.llvm.org/D26594

llvm-svn: 288458
2016-12-02 02:24:42 +00:00
Philip Reames 4d00af1bde Factor out common parts of LVI and Float2Int into ConstantRange [NFCI]
This just extracts out the transfer rules for constant ranges into a single shared point. As it happens, neither bit of code actually overlaps in terms of the handled operators, but with this change that could easily be tweaked in the future.

I also want to have this separated out to make experimenting with a eager value info implementation and possibly a ValueTracking-like fixed depth recursion peephole version. There's no reason all four of these can't share a common implementation which reduces the chances of bugs.

Differential Revision: https://reviews.llvm.org/D27294

llvm-svn: 288413
2016-12-01 20:08:47 +00:00
Peter Collingbourne 863cbfbeba Object: Extract a ModuleSymbolTable class from IRObjectFile.
This class represents a symbol table built from in-memory IR. It provides
access to GlobalValues and should only be used if such access is required
(e.g. in the LTO implementation). We will eventually change IRObjectFile
to read from a bitcode symbol table rather than using ModuleSymbolTable,
so it would not be able to expose the module.

Differential Revision: https://reviews.llvm.org/D27073

llvm-svn: 288319
2016-12-01 06:51:47 +00:00
Philip Reames 812476b495 Revert previous whitespace change
llvm-svn: 288312
2016-12-01 04:37:35 +00:00
Philip Reames d6f7024ae3 Test commit of whitespace to check permissions.
llvm-svn: 288311
2016-12-01 04:37:09 +00:00
Eugene Zelenko a3fe70d233 Fix some Clang-tidy and Include What You Use warnings; other minor fixes (NFC).
This preparation to remove SetVector.h dependency on SmallSet.h.

llvm-svn: 288256
2016-11-30 17:48:10 +00:00
Chandler Carruth 3ab2a5a824 [PM] Extend the explicit 'invalidate' method API on analysis results to
accept an Invalidator that allows them to invalidate themselves if their
dependencies are in turn invalidated.

Rather than recording the dependency graph ahead of time when analysis
get results from other analyses, this simply lets each result trigger
the immediate invalidation of any analyses they actually depend on. They
do this in a way that has three nice properties:

1) They don't have to handle transitive dependencies because the
   infrastructure will recurse for them.
2) The invalidate methods are still called only once. We just
   dynamically discover the necessary topological ordering, everything
   is memoized nicely.
3) The infrastructure still provides a default implementation and can
   access it so that only analyses which have dependencies need to do
   anything custom.

To make this work at all, the invalidation logic also has to defer the
deletion of the result objects themselves so that they can remain alive
until we have collected the complete set of results to invalidate.

A unittest is added here that has exactly the dependency pattern we are
concerned with. It hit the use-after-free described by Sean in much
detail in the long thread about analysis invalidation before this
change, and even in an intermediate form of this change where we failed
to defer the deletion of the result objects.

There is an important problem with doing dependency invalidation that
*isn't* solved here: we don't *enforce* that results correctly
invalidate all the analyses whose results they depend on.

I actually looked at what it would take to do that, and it isn't as hard
as I had thought but the complexity it introduces seems very likely to
outweigh the benefit. The technique would be to provide a base class for
an analysis result that would be populated with other results, and
automatically provide the invalidate method which immediately does the
correct thing. This approach has some nice pros IMO:
- Handles the case we care about and nothing else: only *results*
  that depend on other analyses trigger extra invalidation.
- Localized to the result rather than centralized in the analysis
  manager.
- Ties the storage of the reference to another result to the triggering
  of the invalidation of that analysis.
- Still supports extending invalidation in customized ways.

But the down sides here are:
- Very heavy-weight meta-programming is needed to provide this base
  class.
- Requires a pretty awful API for accessing the dependencies.

Ultimately, I fear it will not pull its weight. But we can re-evaluate
this at any point if we start discovering consistent problems where the
invalidation and dependencies get out of sync. It will fit as a clean
layer on top of the facilities in this patch that we can add if and when
we need it.

Note that I'm not really thrilled with the names for these APIs... The
name "Invalidator" seems ok but not great. The method name "invalidate"
also. In review some improvements were suggested, but they really need
*other* uses of these terms to be updated as well so I'm going to do
that in a follow-up commit.

I'm working on the actual fixes to various analyses that need to use
these, but I want to try to get tests for each of them so we don't
regress. And those changes are seperable and obvious so once this goes
in I should be able to roll them out throughout LLVM.

Many thanks to Sean, Justin, and others for help reviewing here.

Differential Revision: https://reviews.llvm.org/D23738

llvm-svn: 288077
2016-11-28 22:04:31 +00:00
Chandler Carruth 0c6efff178 [PM] Remove weird marking of invalidated analyses as "preserved".
This never made a lot of sense. They've been invalidated for one IR unit
but they aren't really preserved in any normal sense. It seemed like it
would be an elegant way of communicating to outer IR units that pass
managers and adaptors had already handled invalidation, but we've since
ended up adding sets that model this more clearly: we're now using
the 'AllAnalysesOn<IRUnitT>' set to handle cases where the trick of
"preserving" invalidated analyses didn't work.

This patch moves to rely on that technique exclusively and removes the
cumbersome API aspect of updating the preserved set when doing
invalidation. This in turn will simplify a *number* of upcoming patches.

This has a side benefit of exposing a number of places where we were
failing to mark the 'AllAnalysesOn<IRUnitT>' set as preserved. This
patch fixes those, and with those fixes shouldn't change any observable
behavior.

llvm-svn: 288023
2016-11-28 10:42:21 +00:00
Sanjay Patel 8ca30ab0c5 [InstSimplify] allow integer vector types to use computeKnownBits
Note that the non-splat lshr+lshr test folded, but that does not
work in general. Something is missing or wrong in computeKnownBits
as the non-splat shl+shl test still shows.

llvm-svn: 288005
2016-11-27 21:07:28 +00:00
Chandler Carruth dab4eae274 [PM] Change the static object whose address is used to uniquely identify
analyses to have a common type which is enforced rather than using
a char object and a `void *` type when used as an identifier.

This has a number of advantages. First, it at least helps some of the
confusion raised in Justin Lebar's code review of why `void *` was being
used everywhere by having a stronger type that connects to documentation
about this.

However, perhaps more importantly, it addresses a serious issue where
the alignment of these pointer-like identifiers was unknown. This made
it hard to use them in pointer-like data structures. We were already
dodging this in dangerous ways to create the "all analyses" entry. In
a subsequent patch I attempted to use these with TinyPtrVector and
things fell apart in a very bad way.

And it isn't just a compile time or type system issue. Worse than that,
the actual alignment of these pointer-like opaque identifiers wasn't
guaranteed to be a useful alignment as they were just characters.

This change introduces a type to use as the "key" object whose address
forms the opaque identifier. This both forces the objects to have proper
alignment, and provides type checking that we get it right everywhere.
It also makes the types somewhat less mysterious than `void *`.

We could go one step further and introduce a truly opaque pointer-like
type to return from the `ID()` static function rather than returning
`AnalysisKey *`, but that didn't seem to be a clear win so this is just
the initial change to get to a reliably typed and aligned object serving
is a key for all the analyses.

Thanks to Richard Smith and Justin Lebar for helping pick plausible
names and avoid making this refactoring many times. =] And thanks to
Sean for the super fast review!

While here, I've tried to move away from the "PassID" nomenclature
entirely as it wasn't really helping and is overloaded with old pass
manager constructs. Now we have IDs for analyses, and key objects whose
address can be used as IDs. Where possible and clear I've shortened this
to just "ID". In a few places I kept "AnalysisID" to make it clear what
was being identified.

Differential Revision: https://reviews.llvm.org/D27031

llvm-svn: 287783
2016-11-23 17:53:26 +00:00
Chandler Carruth 9eb857cb84 [LCG] Add a previously missing assert about the relationship of RefSCCs.
No intended change, everything seems to be in working order already.

llvm-svn: 287705
2016-11-22 21:40:10 +00:00
Chandler Carruth bae595b742 [LCG] Add utilities to compute parent and ascestor relationships between
SCCs.

These will be fairly expensive routines to call and might be abused in
real code, but are quite useful when debugging or in asserts and are
reasonable and well formed properties to query.

I've used one of them in an assert that was requested in a code review
here. In subsequent commits I'll start using these routines more
heavily, for example in unittests etc. But this at least gets the
groundwork in place.

Differential Revision: https://reviews.llvm.org/D25506

llvm-svn: 287682
2016-11-22 19:23:31 +00:00
Peter Collingbourne 0a4fc46321 Analysis: gep inbounds (gep inbounds (...)) is inbounds.
Differential Revision: https://reviews.llvm.org/D26441

llvm-svn: 287604
2016-11-22 01:03:40 +00:00
Marcin Koscielnicki 6af8e6c3d5 [TLI] Fix breakage introduced by D21739.
The initialize function has an early return for AMDGPU targets.  If taken,
the ShouldExtI32* initialization code will not be executed, resulting in
invalid values in the corresponding fields.  Fix this by moving the code
to the top of the function.

llvm-svn: 287570
2016-11-21 20:20:39 +00:00
Yaxun Liu 02f75f31e0 Fix known zero bits for addrspacecast.
Currently LLVM assumes that a pointer addrspacecasted to a different addr space is equivalent to trunc or zext bitwise, which is not true. For example, in amdgcn target, when a null pointer is addrspacecasted from addr space 4 to 0, its value is changed from i64 0 to i32 -1.

This patch teaches LLVM not to assume known bits of addrspacecast instruction to its operand.

Differential Revision: https://reviews.llvm.org/D26803

llvm-svn: 287545
2016-11-21 15:42:31 +00:00
Marcin Koscielnicki 5ae2c526db [TLI] Add functions determining if int parameters/returns should be zeroext/signext.
On some architectures (s390x, ppc64, sparc64, mips), C-level int is passed
as i32 signext instead of plain i32.  Likewise, unsigned int may be passed
as i32, i32 signext, or i32 zeroext depending on the platform.  Add this
information to TargetLibraryInfo, to be used whenever some LLVM pass
inserts a compiler-rt call to a function involving int parameters
or returns.

Differential Revision: http://reviews.llvm.org/D21739

llvm-svn: 287533
2016-11-21 11:57:11 +00:00
Simon Pilgrim f2fbf43704 Fix comment typos. NFC.
Identified by Pedro Giffuni in PR27636.

llvm-svn: 287490
2016-11-20 13:47:59 +00:00
Daniil Fukalov 4c3322cc84 [SCEV] limit recursion depth of CompareSCEVComplexity
Summary:
CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled loop) and runs almost infinite time.

Added cache of "equal" SCEV pairs to earlier cutoff of further estimation. Recursion depth limit was also introduced as a parameter.

Reviewers: sanjoy

Subscribers: mzolotukhin, tstellarAMD, llvm-commits

Differential Revision: https://reviews.llvm.org/D26389

llvm-svn: 287232
2016-11-17 16:07:52 +00:00
Chris Bieneman 05c279fc4b [CMake] NFC. Updating CMake dependency specifications
This patch updates a bunch of places where add_dependencies was being explicitly called to add dependencies on intrinsics_gen to instead use the DEPENDS named parameter. This cleanup is needed for a patch I'm working on to add a dependency debugging mode to the build system.

llvm-svn: 287206
2016-11-17 04:36:50 +00:00
Daniil Fukalov e870398e48 test commit, changed tab to spaces, NFC
llvm-svn: 287116
2016-11-16 16:41:40 +00:00
Kuba Brecka ddfdba3b01 [tsan] Add support for C++ exceptions into TSan (call __tsan_func_exit during unwinding), LLVM part
This adds support for TSan C++ exception handling, where we need to add extra calls to __tsan_func_exit when a function is exitted via exception mechanisms. Otherwise the shadow stack gets corrupted (leaked). This patch moves and enhances the existing implementation of EscapeEnumerator that finds all possible function exit points, and adds extra EH cleanup blocks where needed.

Differential Revision: https://reviews.llvm.org/D26177

llvm-svn: 286893
2016-11-14 21:41:13 +00:00
Teresa Johnson 3624bdf60a Restore "[ThinLTO] Prevent exporting of locals used/defined in module level asm"
This restores the rest of r286297 (part was restored in r286475).
Specifically, it restores the part requiring adding a dependency from
the Analysis to Object library (downstream use changed to correctly
model split BitReader vs BitWriter libraries).

Original description of this part of patch follows:

Module level asm may also contain defs of values. We need to prevent
export of any refs to local values defined in module level asm (e.g. a
ref in normal IR), since that also requires renaming/promotion of the
local. To do that, the summary index builder looks at all values in the
module level asm string that are not marked Weak or Global, which is
exactly the set of locals that are defined. A summary is created for
each of these local defs and flagged as NoRename.

This required adding handling to the BitcodeWriter to look at GV
declarations to see if they have a summary (rather than skipping them
all).

Finally, added an assert to IRObjectFile::CollectAsmUndefinedRefs to
ensure that an MCAsmParser is available, otherwise the module asm parse
would silently fail. Initialized the asm parser in the opt tool for use
in testing this fix.

Fixes PR30610.

llvm-svn: 286844
2016-11-14 17:12:32 +00:00
Teresa Johnson d5033a4576 [ThinLTO] Make inline assembly handling more efficient in summary
Summary:
The change in r285513 to prevent exporting of locals used in
inline asm added all locals in the llvm.used set to the reference
set of functions containing inline asm. Since these locals were marked
NoRename, this automatically prevented importing of the function.

Unfortunately, this caused an explosion in the summary reference lists
in some cases. In my particular example, it happened for a large protocol
buffer generated C++ file, where many of the generated functions
contained an inline asm call. It was exacerbated when doing a ThinLTO
PGO instrumentation build, where the PGO instrumentation included
thousands of private __profd_* values that were added to llvm.used.

We really only need to include a single llvm.used local (NoRename) value
in the reference list of a function containing inline asm to block it
being imported. However, it seems cleaner to add a flag to the summary
that explicitly describes this situation, which is what this patch does.

Reviewers: mehdi_amini

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D26402

llvm-svn: 286840
2016-11-14 16:40:19 +00:00
James Molloy 6df8f27c95 [InlineCost] Remove skew when calculating call costs
When calculating the cost of a call instruction we were applying a heuristic penalty as well as the cost of the instruction itself.

However, when calculating the benefit from inlining we weren't discounting the equivalent penalty for the call instruction that would be removed! This caused skew in the calculation and meant we wouldn't inline in the following, trivial case:

  int g() {
    h();
  }
  int f() {
    g();
  }

llvm-svn: 286814
2016-11-14 11:14:41 +00:00