348 Commits

Author SHA1 Message Date
Sean Silva
2d9fa979fc Avoid using a raw AssumptionCacheTracker in various inliner functions.
This unblocks the new PM part of River's patch in
https://reviews.llvm.org/D22706

Conveniently, this same change was needed for D21921 and so these
changes are just spun out from there.

llvm-svn: 276515
2016-07-23 04:22:50 +00:00
Benjamin Kramer
eef5ae3754 Apply clang-tidy's modernize-loop-convert to most of lib/Transforms.
Only minor manual fixes. No functionality change intended.

llvm-svn: 273808
2016-06-26 12:28:59 +00:00
David Majnemer
eecff2722a Revert "[SimplifyCFG] Stop inserting calls to llvm.trap for UB"
This reverts commit r273778, it seems to break UBSan :/

llvm-svn: 273779
2016-06-25 08:19:55 +00:00
David Majnemer
9f643fc17a [SimplifyCFG] Stop inserting calls to llvm.trap for UB
SimplifyCFG had logic to insert calls to llvm.trap for two very
particular IR patterns: stores and invokes of undef/null.

While InstCombine canonicalizes certain undefined behavior IR patterns
to stores of undef, phase ordering means that this cannot be relied upon
in general.

There are much better tools than llvm.trap: UBSan and ASan.

N.B. I could be argued into reverting this change if a clear argument as
to why it is important that we synthesize llvm.trap for stores, I'd be
hard pressed to see why it'd be useful for invokes...

llvm-svn: 273778
2016-06-25 08:04:19 +00:00
David Majnemer
f2b411238d Switch more loops to be range-based
This makes the code a little more concise, no functional change is
intended.

llvm-svn: 273644
2016-06-24 04:05:21 +00:00
Benjamin Kramer
5699dda316 Run clang-tidy's performance-unnecessary-copy-initialization over LLVM.
No functionality change intended.

llvm-svn: 272516
2016-06-12 17:30:47 +00:00
Benjamin Kramer
e80783f62f Pass DebugLoc and SDLoc by const ref.
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512
2016-06-12 15:39:02 +00:00
Sanjoy Das
ee178ad6c3 All llvm.deoptimize declarations must use the same calling convention
This new verifier rule lets us unambigously pick a calling convention
when creating a new declaration for
`@llvm.experimental.deoptimize.<ty>`.  It is also congruent with our
lowering strategy -- since all calls to `@llvm.experimental.deoptimize`
are lowered to calls to `__llvm_deoptimize`, it is reasonable to enforce
a unique calling convention.

Some of the tests that were breaking this verifier rule have had to be
split up into different .ll files.

The inliner was violating this rule as well, and has been fixed to avoid
producing invalid IR.

llvm-svn: 269261
2016-05-12 01:17:38 +00:00
Hal Finkel
5a6e2ec855 [Inliner] Preserve llvm.mem.parallel_loop_access metadata
When inlining a call site with llvm.mem.parallel_loop_access metadata, this
metadata needs to be propagated to all cloned memory-accessing instructions.
Otherwise, inlining parts of the loop body will invalidate the annotation.

With this functionality, we now vectorize the following as expected:

  void Body(int *res, int *c, int *d, int *p, int i) {
    res[i] = (p[i] == 0) ? res[i] : res[i] + d[i];
  }

  void Test(int *res, int *c, int *d, int *p, int n) {
    int i;

  #pragma clang loop vectorize(assume_safety)
    for (i = 0; i < 1600; i++) {
      Body(res, c, d, p, i);
    }
  }

llvm-svn: 267949
2016-04-28 23:00:04 +00:00
Sanjoy Das
85af6d6f07 Maintain calling convention when inling calls to llvm.deoptimize
The behavior here was buggy -- we'd forget the calling convention after
inlining a callsite calling llvm.deoptimize.

llvm-svn: 265867
2016-04-09 00:22:59 +00:00
Sanjoy Das
1181cf88c4 Don't insert stackrestore on deoptimizing returns
They're not necessary (since the stack pointer is trivially restored on
return), and the way LLVM inserts the stackrestore calls breaks the
IR (we get a stackrestore between the deoptimize call and the return).

llvm-svn: 265101
2016-04-01 02:51:30 +00:00
Sanjoy Das
748992028c Don't insert lifetime end markers on deoptimizing returns
They're not necessary (since the lifetime of the alloca is trivially
over due to the return), and the way LLVM inserts the lifetime.end
markers breaks the IR (we get a lifetime end marker between the
deoptimize call and the return).

llvm-svn: 265100
2016-04-01 02:51:26 +00:00
Sanjoy Das
f200766275 Introduce a @llvm.experimental.guard intrinsic
Summary:
As discussed on llvm-dev[1].

This change adds the basic boilerplate code around having this intrinsic
in LLVM:

 - Changes in Intrinsics.td, and the IR Verifier
 - A lowering pass to lower @llvm.experimental.guard to normal
   control flow
 - Inliner support

[1]: http://lists.llvm.org/pipermail/llvm-dev/2016-February/095523.html

Reviewers: reames, atrick, chandlerc, rnk, JosephTremoulet, echristo

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18527

llvm-svn: 264976
2016-03-31 00:18:46 +00:00
Sanjoy Das
3b791814db Introduce @llvm.experimental.deoptimize
Summary:
This intrinsic, together with deoptimization operand bundles, allow
frontends to express transfer of control and frame-local state from
one (typically more specialized, hence faster) version of a function
into another (typically more generic, hence slower) version.

In languages with a fully integrated managed runtime this intrinsic can
be used to implement "uncommon trap" like functionality.  In unmanaged
languages like C and C++, this intrinsic can be used to represent the
slow paths of specialized functions.

Note: this change does not address how `@llvm.experimental_deoptimize`
is lowered.  That will be done in a later change.

Reviewers: chandlerc, rnk, atrick, reames

Subscribers: llvm-commits, kmod, mjacob, maksfb, mcrosier, JosephTremoulet

Differential Revision: http://reviews.llvm.org/D17732

llvm-svn: 263281
2016-03-11 19:08:34 +00:00
Easwaran Raman
7383a70795 Revert revisions 262636, 262643, 262679, and 262682.
llvm-svn: 262883
2016-03-08 00:36:35 +00:00
Easwaran Raman
587391856c Fix a use-after-free bug introduced in r262636
llvm-svn: 262679
2016-03-04 00:44:01 +00:00
Easwaran Raman
ff8cc9e544 Infrastructure for PGO enhancements in inliner
This patch provides the following infrastructure for PGO enhancements in inliner:

Enable the use of block level profile information in inliner
Incremental update of block frequency information during inlining
Update the function entry counts of callees when they get inlined into callers.

Differential Revision: http://reviews.llvm.org/D16381

llvm-svn: 262636
2016-03-03 18:26:33 +00:00
David Majnemer
29ae1c3d76 [WinEH] Don't inline an 'unwinds to caller' cleanupret into funclets which locally unwind
It is problematic if the inlinee has a cleanupret which unwinds to
caller and we inline it into a call site which doesn't unwind.

If the funclet unwinds anywhere other than to the caller,
then we will give the funclet two unwind destinations.
This will result in a verifier failure.

Seeing as how the caller wasn't an invoke (which would locally unwind)
and that the funclet cannot unwind to caller, we must conclude that an
'unwind to caller' cleanupret is dynamically unreachable.

This fixes PR26698.

Differential Revision: http://reviews.llvm.org/D17536

llvm-svn: 261656
2016-02-23 17:11:04 +00:00
Joseph Tremoulet
de5c9a8723 [Inliner/WinEH] Honor implicit nounwinds
Summary:
Funclet EH tables require that a given funclet have only one unwind
destination for exceptional exits.  The verifier will therefore reject
e.g. two cleanuprets with different unwind dests for the same cleanup, or
two invokes exiting the same funclet but to different unwind dests.
Because catchswitch has no 'nounwind' variant, and because IR producers
are not *required* to annotate calls which will not unwind as 'nounwind',
it is legal to nest a call or an "unwind to caller" catchswitch within a
funclet pad that has an unwind destination other than caller; it is
undefined behavior for such a call or catchswitch to unwind.

Normally when inlining an invoke, calls in the inlined sequence are
rewritten to invokes that unwind to the callsite invoke's unwind
destination, and "unwind to caller" catchswitches in the inlined sequence
are rewritten to unwind to the callsite invoke's unwind destination.
However, if such a call or "unwind to caller" catchswitch is located in a
callee funclet that has another exceptional exit with an unwind
destination within the callee, applying the normal transformation would
give that callee funclet multiple unwind destinations for its exceptional
exits.  There would be no way for EH table generation to determine which
is the "true" exit, and the verifier would reject the function
accordingly.

Add logic to the inliner to detect these cases and leave such calls and
"unwind to caller" catchswitches as calls and "unwind to caller"
catchswitches in the inlined sequence.

This fixes PR26147.


Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: alexcrichton, llvm-commits

Differential Revision: http://reviews.llvm.org/D16319

llvm-svn: 258273
2016-01-20 02:15:15 +00:00
Joseph Tremoulet
b8804f1378 [OperandBundles] Copy DebugLoc with calls/invokes
Summary:
The overloads of CallInst::Create and InvokeInst::Create that are used to
adjust operand bundles purport to create a new instruction "identical in
every way except [for] the operand bundles", so copy the DebugLoc along
with everything else.


Reviewers: sanjoy, majnemer

Subscribers: majnemer, dblaikie, llvm-commits

Differential Revision: http://reviews.llvm.org/D16157

llvm-svn: 257745
2016-01-14 06:21:42 +00:00
Sanjay Patel
08498645a0 hasNUses(0) == use_empty() ; NFCI
Also, improve variable name and remove unnecessary braces.

llvm-svn: 257687
2016-01-13 22:16:48 +00:00
Sanjay Patel
2747253c1e rangify; NFCI
llvm-svn: 257677
2016-01-13 21:39:26 +00:00
Sanjoy Das
d080ee893d Nonnull elements in OperandBundleCallSites are not all Instructions
`CloneAndPruneIntoFromInst` sometimes RAUW's dead instructions with
`undef` before erasing them (to avoid deleting instructions that still
have uses).  This changes the `WeakVH` in `OperandBundleCallSites` to
hold an `undef`, and we need to guard for this situation in eventuality
in `llvm::InlineFunction`.

llvm-svn: 256110
2015-12-19 22:40:28 +00:00
David Majnemer
608538dccc [WinEH] Use operand bundles to describe call sites
SimplifyCFG allows tail merging with code which terminates in
unreachable which, in turn, makes it possible for an invoke to end up in
a funclet which it was not originally part of.

Using operand bundles on invokes allows us to determine whether or not
an invoke was part of a funclet in the source program.

Furthermore, it allows us to unambiguously answer questions about the
legality of inlining into call sites which the personality may have
trouble with.

Differential Revision: http://reviews.llvm.org/D15517

llvm-svn: 255674
2015-12-15 21:27:27 +00:00
David Majnemer
49dcd13916 [IR] Remove terminatepad
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function.  This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.

Depends on D15478.

Differential Revision: http://reviews.llvm.org/D15479

llvm-svn: 255522
2015-12-14 18:34:23 +00:00
David Majnemer
bf189bdcd7 [IR] Reformulate LLVM's EH funclet IR
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
  but they are difficult to explain to others, even to seasoned LLVM
  experts.
- catchendpad and cleanupendpad are optimization barriers.  They cannot
  be split and force all potentially throwing call-sites to be invokes.
  This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
  It is unsplittable, starts a funclet, and has control flow to other
  funclets.
- The nesting relationship between funclets is currently a property of
  control flow edges.  Because of this, we are forced to carefully
  analyze the flow graph to see if there might potentially exist illegal
  nesting among funclets.  While we have logic to clone funclets when
  they are illegally nested, it would be nicer if we had a
  representation which forbade them upfront.

Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
  flow, just a bunch of simple operands;  catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
  the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
  the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad.  Their presence can be inferred
  implicitly using coloring information.

N.B.  The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for.  An expert should take a
look to make sure the results are reasonable.

Reviewers: rnk, JosephTremoulet, andrew.w.kaylor

Differential Revision: http://reviews.llvm.org/D15139

llvm-svn: 255422
2015-12-12 05:38:55 +00:00
Sanjoy Das
d85ded90d0 Add arg_begin() and arg_end() to CallInst and InvokeInst; NFCI
- This simplifies the CallSite class, arg_begin / arg_end are now
   simple wrapper getters.

 - In several places, we were creating CallSite instances solely to call
   arg_begin and arg_end.  With this change, that's no longer required.

llvm-svn: 255226
2015-12-10 06:39:02 +00:00
Sanjoy Das
f3ba629c4d Use WeakVH to keep track of calls with operand bundles in CloneCodeInfo
`CloneAndPruneIntoFromInst` can DCE instructions after cloning them into
the new function, and so an AssertingVH is too strong.  This change
switches CloneCodeInfo to use a std::vector<WeakVH>.

llvm-svn: 255148
2015-12-09 20:33:52 +00:00
Sanjoy Das
90bb44dfe3 [OperandBundles] Remove unncessary constructor
The StringRef constructor is unnecessary (since we're converting to
std::string anyway), and having it requires an explicit call to
StringRef's or std::string's constructor.

llvm-svn: 255000
2015-12-08 03:50:32 +00:00
Sanjoy Das
dcc5bddb02 [OperandBundles] Extract duplicated code into a helper function, NFC
llvm-svn: 254047
2015-11-25 00:42:24 +00:00
Weiming Zhao
2d64bb7e78 [Utils] Put includes in correct order. NFC.
Summary:
    Followed the guidelines in:
    http://llvm.org/docs/CodingStandards.html#include-style
    
    However, I noticed that uppercase named headers come before lowercase ones
    throughout the codebase. So kept them as is.
    
    Patch by Mandeep Singh Grang <mgrang@codeaurora.org>

Reviewers: majnemer, davide, jmolloy, atrick

Subscribers: sanjoy

Differential Revision: http://reviews.llvm.org/D14939

llvm-svn: 254005
2015-11-24 18:57:06 +00:00
Pete Cooper
b753649d63 Revert "Change memcpy/memset/memmove to have dest and source alignments."
This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253543
2015-11-19 05:56:52 +00:00
Pete Cooper
aca4c5cdc6 Change memcpy/memset/memmove to have dest and source alignments.
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer.  It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments.  The alignment
argument itself is removed.

There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe.  For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.

For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)

For out of tree owners, I was able to strip alignment from calls using sed by replacing:
  (call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
  $1i1 false)

and similarly for memmove and memcpy.

I then added back in alignment to test cases which needed it.

A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.

In IRBuilder itself, a new argument was added.  Instead of calling:
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
  CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)

There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool.  This is to prevent isVolatile here from passing its default
parameter to the source alignment.

Note, changes in future can now be made to codegen.  I didn't change anything here, but this
change should enable better memcpy code sequences.

Reviewed by Hal Finkel.

llvm-svn: 253511
2015-11-18 22:17:24 +00:00
Sanjoy Das
3bc2ba29a2 [OperandBundles] Tighten OperandBundleDef's interface; NFC
llvm-svn: 253446
2015-11-18 08:30:07 +00:00
Sanjoy Das
f5a4d357df Teach the inliner to track deoptimization state
Summary:
This change teaches LLVM's inliner to track and suitably adjust
deoptimization state (tracked via deoptimization operand bundles) as it
inlines through call sites.  The operation is described in more detail
in the LangRef changes.

Reviewers: reames, majnemer, chandlerc, dexonsmith

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14552

llvm-svn: 253438
2015-11-18 06:23:38 +00:00
Sanjoy Das
b9b521e21e [Inliner] Don't inline through callsites with operand bundles
Summary:
This change teaches the LLVM inliner to not inline through callsites
with unknown operand bundles.  Currently all operand bundles are
"unknown" operand bundles but in the near future we will add support for
inlining through some select kinds of operand bundles.

Reviewers: reames, chandlerc, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14001

llvm-svn: 251141
2015-10-23 20:09:55 +00:00
David Majnemer
e4209346fe [InlineFunction] Correctly inline TerminatePadInst
We forgot to append the terminatepad's arguments which resulted in us
treating the old terminatepad as an argument to the new terminatepad
causing us to crash immediately.  Instead, add the old terminatepad's
arguments to the new terminatepad.

This fixes PR25155.

llvm-svn: 250234
2015-10-13 22:08:17 +00:00
Duncan P. N. Exon Smith
c29917fae7 TransformUtils: Remove implicit ilist iterator conversions, NFC
Continuing the work from last week to remove implicit ilist iterator
conversions.  First related commit was probably r249767, with some more
motivation in r249925.  This edition gets LLVMTransformUtils compiling
without the implicit conversions.

No functional change intended.

llvm-svn: 250142
2015-10-13 02:39:05 +00:00
Hans Wennborg
7d1f4ff326 Fix Clang-tidy modernize-use-nullptr warnings in source directories and generated files; other minor cleanups.
Patch by Eugene Zelenko!

Differential Revision: http://reviews.llvm.org/D13321

llvm-svn: 249482
2015-10-06 23:24:35 +00:00
Vedant Kumar
e39c08a06e [Inline] Use AssumptionCache from the right Function
This changes the behavior of AddAligntmentAssumptions to match its
comment. I.e, prove the asserted alignment in the context of the caller,
not the callee.

Thanks to Mehdi Amini for seeing the issue here! Also to Artur Pilipenko
who also saw a fix for the issue.

rdar://22521387

Differential Revision: http://reviews.llvm.org/D12997

llvm-svn: 248390
2015-09-23 15:49:08 +00:00
Chandler Carruth
d7003090ac [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible
with the new pass manager, and no longer relying on analysis groups.

This builds essentially a ground-up new AA infrastructure stack for
LLVM. The core ideas are the same that are used throughout the new pass
manager: type erased polymorphism and direct composition. The design is
as follows:

- FunctionAAResults is a type-erasing alias analysis results aggregation
  interface to walk a single query across a range of results from
  different alias analyses. Currently this is function-specific as we
  always assume that aliasing queries are *within* a function.

- AAResultBase is a CRTP utility providing stub implementations of
  various parts of the alias analysis result concept, notably in several
  cases in terms of other more general parts of the interface. This can
  be used to implement only a narrow part of the interface rather than
  the entire interface. This isn't really ideal, this logic should be
  hoisted into FunctionAAResults as currently it will cause
  a significant amount of redundant work, but it faithfully models the
  behavior of the prior infrastructure.

- All the alias analysis passes are ported to be wrapper passes for the
  legacy PM and new-style analysis passes for the new PM with a shared
  result object. In some cases (most notably CFL), this is an extremely
  naive approach that we should revisit when we can specialize for the
  new pass manager.

- BasicAA has been restructured to reflect that it is much more
  fundamentally a function analysis because it uses dominator trees and
  loop info that need to be constructed for each function.

All of the references to getting alias analysis results have been
updated to use the new aggregation interface. All the preservation and
other pass management code has been updated accordingly.

The way the FunctionAAResultsWrapperPass works is to detect the
available alias analyses when run, and add them to the results object.
This means that we should be able to continue to respect when various
passes are added to the pipeline, for example adding CFL or adding TBAA
passes should just cause their results to be available and to get folded
into this. The exception to this rule is BasicAA which really needs to
be a function pass due to using dominator trees and loop info. As
a consequence, the FunctionAAResultsWrapperPass directly depends on
BasicAA and always includes it in the aggregation.

This has significant implications for preserving analyses. Generally,
most passes shouldn't bother preserving FunctionAAResultsWrapperPass
because rebuilding the results just updates the set of known AA passes.
The exception to this rule are LoopPass instances which need to preserve
all the function analyses that the loop pass manager will end up
needing. This means preserving both BasicAAWrapperPass and the
aggregating FunctionAAResultsWrapperPass.

Now, when preserving an alias analysis, you do so by directly preserving
that analysis. This is only necessary for non-immutable-pass-provided
alias analyses though, and there are only three of interest: BasicAA,
GlobalsAA (formerly GlobalsModRef), and SCEVAA. Usually BasicAA is
preserved when needed because it (like DominatorTree and LoopInfo) is
marked as a CFG-only pass. I've expanded GlobalsAA into the preserved
set everywhere we previously were preserving all of AliasAnalysis, and
I've added SCEVAA in the intersection of that with where we preserve
SCEV itself.

One significant challenge to all of this is that the CGSCC passes were
actually using the alias analysis implementations by taking advantage of
a pretty amazing set of loop holes in the old pass manager's analysis
management code which allowed analysis groups to slide through in many
cases. Moving away from analysis groups makes this problem much more
obvious. To fix it, I've leveraged the flexibility the design of the new
PM components provides to just directly construct the relevant alias
analyses for the relevant functions in the IPO passes that need them.
This is a bit hacky, but should go away with the new pass manager, and
is already in many ways cleaner than the prior state.

Another significant challenge is that various facilities of the old
alias analysis infrastructure just don't fit any more. The most
significant of these is the alias analysis 'counter' pass. That pass
relied on the ability to snoop on AA queries at different points in the
analysis group chain. Instead, I'm planning to build printing
functionality directly into the aggregation layer. I've not included
that in this patch merely to keep it smaller.

Note that all of this needs a nearly complete rewrite of the AA
documentation. I'm planning to do that, but I'd like to make sure the
new design settles, and to flesh out a bit more of what it looks like in
the new pass manager first.

Differential Revision: http://reviews.llvm.org/D12080

llvm-svn: 247167
2015-09-09 17:55:00 +00:00
Joseph Tremoulet
bce9d857cc [WinEH] Add cleanupendpad instruction
Summary:
Add a `cleanupendpad` instruction, used to mark exceptional exits out of
cleanups (for languages/targets that can abort a cleanup with another
exception).  The `cleanupendpad` instruction is similar to the `catchendpad`
instruction in that it is an EH pad which is the target of unwind edges in
the handler and which itself has an unwind edge to the next EH action.
The `cleanupendpad` instruction, similar to `cleanupret` has a `cleanuppad`
argument indicating which cleanup it exits.  The unwind successors of a
`cleanuppad`'s `cleanupendpad`s must agree with each other and with its
`cleanupret`s.

Update WinEHPrepare (and docs/tests) to accomodate `cleanupendpad`.

Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12433

llvm-svn: 246751
2015-09-03 09:09:43 +00:00
Joseph Tremoulet
56089ea65e [WinEH] Require token linkage in EH pad/ret signatures
Summary:
WinEHPrepare is going to require that cleanuppad and catchpad produce values
of token type which are consumed by any cleanupret or catchret exiting the
pad.  This change updates the signatures of those operators to require/enforce
that the type produced by the pads is token type and that the rets have an
appropriate argument.

The catchpad argument of a `CatchReturnInst` must be a `CatchPadInst` (and
similarly for `CleanupReturnInst`/`CleanupPadInst`).  To accommodate that
restriction, this change adds a notion of an operator constraint to both
LLParser and BitcodeReader, allowing appropriate sentinels to be constructed
for forward references and appropriate error messages to be emitted for
illegal inputs.

Also add a verifier rule (noted in LangRef) that a catchpad with a catchpad
predecessor must have no other predecessors; this ensures that WinEHPrepare
will see the expected linear relationship between sibling catches on the
same try.

Lastly, remove some superfluous/vestigial casts from instruction operand
setters operating on BasicBlocks.

Reviewers: rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12108

llvm-svn: 245797
2015-08-23 00:26:33 +00:00
David Majnemer
10f2d9234b [IR] Add token types
This introduces the basic functionality to support "token types".
The motivation stems from the need to perform operations on a Value
whose provenance cannot be obscured.

There are several applications for such a type but my immediate
motivation stems from WinEH.  Our personality routine enforces a
single-entry - single-exit regime for cleanups.  After several rounds of
optimizations, we may be left with a terminator whose "cleanup-entry
block" is not entirely clear because control flow has merged two
cleanups together.  We have experimented with using labels as operands
inside of instructions which are not terminators to indicate where we
came from but found that LLVM does not expect such exotic uses of
BasicBlocks.

Instead, we can use this new type to clearly associate the "entry point"
and "exit point" of our cleanup.  This is done by having the cleanuppad
yield a Token and consuming it at the cleanupret.
The token type makes it impossible to obscure or otherwise hide the
Value, making it trivial to track the relationship between the two
points.

What is the burden to the optimizer?  Well, it turns out we have already
paid down this cost by accepting that there are certain calls that we
are not permitted to duplicate, optimizations have to watch out for
such instructions anyway.  There are additional places in the optimizer
that we will probably have to update but early examination has given me
the impression that this will not be heroic.

Differential Revision: http://reviews.llvm.org/D11861

llvm-svn: 245029
2015-08-14 05:09:07 +00:00
David Majnemer
34ee3789f3 New EH representation for MSVC compatibility
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support.  Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.

Differential Revision: http://reviews.llvm.org/D11097

llvm-svn: 243766
2015-07-31 17:58:14 +00:00
Pete Cooper
a8e3702859 Use make_range(rbegin(), rend()) to allow foreach loops. NFC.
Instead of the pattern

for (auto I = x.rbegin(), E = x.end(); I != E; ++I)

we can use make_range to construct the reverse range and iterate using
that instead.

llvm-svn: 243163
2015-07-24 21:13:43 +00:00
Chandler Carruth
2e896f4f08 [PM/AA] Extract the ModRef enums from the AliasAnalysis class in
preparation for de-coupling the AA implementations.

In order to do this, they had to become fake-scoped using the
traditional LLVM pattern of a leading initialism. These can't be actual
scoped enumerations because they're bitfields and thus inherently we use
them as integers.

I've also renamed the behavior enums that are specific to reasoning
about the mod/ref behavior of functions when called. This makes it more
clear that they have a very narrow domain of applicability.

I think there is a significantly cleaner API for all of this, but
I don't want to try to do really substantive changes for now, I just
want to refactor the things away from analysis groups so I'm preserving
the exact original design and just cleaning up the names, style, and
lifting out of the class.

Differential Revision: http://reviews.llvm.org/D10564

llvm-svn: 242963
2015-07-22 23:15:57 +00:00
Alexander Kornienko
f993659b8f Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Alexander Kornienko
40cb19d802 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
David Majnemer
c8b1f095a3 Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00