Commit Graph

120 Commits

Author SHA1 Message Date
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Adrian Prantl b8089516a5 testcase gardening: update the emissionKind enum to the new syntax. (NFC)
llvm-svn: 265081
2016-04-01 00:16:49 +00:00
David Majnemer e60ee3b8ce [WinEH] Make setjmp work correctly with EH
32-bit X86 EH on Windows utilizes a stack of registration nodes
allocated and deallocated on entry/exit.  A registration node contains a
bunch of EH personality specific information like which try-state we are
currently in.

Because a setjmp target allows control flow from arbitrary program
points, there is no way to ensure that the try-state we are in is
correctly updated once we transfer control.

MSVC compatible compilers, like MSVC and ICC, utilize runtime helpers to
reinitialize the try-state when a longjmp occurs.  This is implemented
by adding additional arguments to _setjmp3: the desired try-state and
a helper routine to update the try-state.

Differential Revision: http://reviews.llvm.org/D17721

llvm-svn: 262241
2016-02-29 19:16:03 +00:00
David Majnemer 08dd52dc75 [WinEH] Don't remove unannotated inline-asm calls
Inline-asm calls aren't annotated with funclet bundle operands because
they don't throw and cannot be inlined through.  We shouldn't require
them to bear an funclet bundle operand.

llvm-svn: 261942
2016-02-26 00:04:25 +00:00
David Majnemer 17525aba8a [WinEH] Visit 'unwind to caller' catchswitches nested in catchswitches
We had the right logic for the nested cleanuppad case but omitted it for
catchswitches.

llvm-svn: 261615
2016-02-23 07:18:15 +00:00
David Majnemer 7e5937b775 [WinEH] Optimize WinEH state stores
32-bit x86 Windows targets use a linked-list of nodes allocated on the
stack, referenced to via thread-local storage.  The personality routine
interprets one of the fields in the node as a 'state number' which
indicates where the personality routine should transfer control.

State transitions are possible only before call-sites which may throw
exceptions.  Our previous scheme had us update the state number before
all call-sites which may throw.

Instead, we can try to minimize the number of times we need to store by
reasoning about the nearest store which dominates the current call-site.
If the last store agrees with the current call-site, then we know that
the state-update is redundant and can be elided.

This is largely straightforward: an RPO walk of the blocks allows us to
correctly forward propagate the information when the function is a DAG.
Currently, loops are not handled optimally and may trigger superfluous
state stores.

Differential Revision: http://reviews.llvm.org/D16763

llvm-svn: 261122
2016-02-17 18:37:11 +00:00
Andrew Kaylor d1188ddd33 [WinEH] Prevent EH state numbering from skipping nested cleanup pads that never return
Differential Revision: http://reviews.llvm.org/D17208

llvm-svn: 260733
2016-02-12 21:10:16 +00:00
David Majnemer 784d4a455b Revert r258580 and r258581.
Those commits created an artificial edge from a cleanup to a synthesized
catchswitch in order to get the MSVC personality routine to execute
cleanups which don't cleanupret and are not wrapped by a catchswitch.

This worked well enough but is not a complete solution in situations
where there the cleanup infinite loops.

However, the real deal breaker behind this approach comes about from a
degenerate case where the cleanup is post-dominated by unreachable *and*
throws an exception.  This ends poorly because the catchswitch will
inadvertently catch the exception.

Because of this we should go back to our previous behavior of not
executing certain cleanups (identical behavior with the Itanium ABI
implementation in clang, GCC and ICC).

N.B. I think this could be salvaged by making the catchpad rethrow the
exception and properly transforming throwing calls in the cleanup into
invokes.

llvm-svn: 259338
2016-02-01 03:29:38 +00:00
David Majnemer f2bb710da5 [WinEH] Don't perform state stores in cleanups
Our cleanups do not support true lexical nesting of funclets which
obviates the need to perform state stores.

This fixes PR26361.

llvm-svn: 259161
2016-01-29 05:33:15 +00:00
David Majnemer b7d49268c2 [WinEH] Don't miscompile cleanups which conditionally unwind to caller
A cleanup can have paths which unwind or end up in unreachable.
If there is an unreachable path *and* a path which unwinds to caller,
we would mistakenly inject an unwind path to a catchswitch on the
unreachable path.  This results in a verifier assertion firing because
the cleanup unwinds to two different places: to the caller and to the
catchswitch.

This occured because we used getCleanupRetUnwindDest to determine if the
cleanuppad had no cleanuprets.
This is incorrect, getCleanupRetUnwindDest returns null for cleanuprets
which unwind to caller.

llvm-svn: 258651
2016-01-23 23:54:33 +00:00
David Majnemer f1ff538456 [WinEH] Let cleanups post-dominated by unreachable get executed
Cleanups in C++ are a little weird.  They are only guaranteed to be
reliably executed if, and only if, there is a viable catch handler which
can handle the exception.

This means that reachability of a cleanup is lexically determined by it
being nested with a try-block which unwinds to a catch.  It is *cannot*
be reasoned about by examining the control flow edges leaving a cleanup.

Usually this is not a problem.  It becomes a problem when there are *no*
edges out of a cleanup because we believed that code post-dominated by
the cleanup is dead.  In LLVM's case, this code is what informs the
personality routine about the presence of a suitable catch handler.
However, the lack of edges to that catch handler makes the handler
become unreachable which causes us to remove it.  By removing the
handler, the cleanup becomes unreachable.

Instead, inject a catch-all handler with every cleanup that has no
unwind edges.  This will allow us to properly unwind the stack.

This fixes PR25997.

llvm-svn: 258580
2016-01-22 23:20:43 +00:00
Joseph Tremoulet 8ea8086322 [WinEH] Disallow cyclic unwinds
Summary:
Funclet-based EH personalities/tables likely can't handle these, and they
can't be generated at source, so make them officially illegal in IR as
well.


Reviewers: andrew.w.kaylor, rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15963

llvm-svn: 257274
2016-01-10 04:31:05 +00:00
Joseph Tremoulet 81e81960e3 [WinEH] Verify consistent funclet unwind exits
Summary:
A funclet EH pad may be exited by an unwind edge, which may be a
cleanupret exiting its cleanuppad, an invoke exiting a funclet, or an
unwind out of a nested funclet transitively exiting its parent.  Funclet
EH personalities require all such exceptional exits from a given funclet to
have the same unwind destination, and EH preparation / state numbering /
table generation implicitly depends on this.  Formalize it as a rule of
the IR in the LangRef and verifier.


Reviewers: rnk, majnemer, andrew.w.kaylor

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15962

llvm-svn: 257273
2016-01-10 04:30:02 +00:00
Joseph Tremoulet 71e5676de4 [WinEH] Update catchrets with cloned successors
Summary:
Add a pass to update catchrets when their successors get cloned; the
existing pass doesn't catch these because it walks the funclet whose
blocks are being cloned but the catchret is in a child funclet.

Also update the test for removing incoming PHI values; when the
predecessor is a catchret, the relevant color is the catchret's parentPad,
not its block's color.


Reviewers: andrew.w.kaylor, rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15840

llvm-svn: 256689
2016-01-02 15:22:36 +00:00
David Majnemer c640f863e0 [WinEH] Don't visit the same catchswitch twice
We visited the same catchswitch twice because it was both the child of
another funclet and the predecessor of a cleanuppad.

Instead, change the numbering algorithm to only recurse if the unwind
destination of the inner funclet agrees with the unwind destination of
the catchswitch.

This fixes PR25926.

llvm-svn: 256317
2015-12-23 03:59:04 +00:00
David Majnemer 3bb88c0210 [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 bbfc7219ef [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 8a1c45d6e8 [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
Reid Kleckner cc2f6c35a3 [WinEH] Disable most forms of demotion
Now that the register allocator knows about the barriers on funclet
entry and exit, testing has shown that this is unnecessary.

We still demote PHIs on unsplittable blocks due to the differences
between the IR CFG and the Machine CFG.

llvm-svn: 253619
2015-11-19 23:23:33 +00:00
Joseph Tremoulet 149c433bcc [WinEH] Find root frame correctly in CLR funclets
Summary:
The value that the CoreCLR personality passes to a funclet for the
establisher frame may be the root function's frame or may be the parent
funclet's (mostly empty) frame in the case of nested funclets.  Each
funclet stores a pointer to the root frame in its own (mostly empty)
frame, as does the root function itself.  All frames allocate this slot at
the same offset, measured from the post-prolog stack pointer, so that the
same sequence can accept any ancestor as an establisher frame parameter
value, and so that a single offset can be reported to the GC, which also
looks at this slot.

This change allocate the slot when processing function entry, and records
its frame index on the WinEHFuncInfo object, then inserts the code to
set/copy it during prolog emission.


Reviewers: majnemer, AndyAyers, pgavlin, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14614

llvm-svn: 252983
2015-11-13 00:39:23 +00:00
Andrew Kaylor fdd48fa1e1 [WinEH] Re-committing r252249 (Clone funclets with multiple parents) with additional fixes for determinism problems
Differential Revision: http://reviews.llvm.org/D14454

llvm-svn: 252508
2015-11-09 19:59:02 +00:00
Joseph Tremoulet f748c8937e [WinEH] Update exception pointer registers
Summary:
The CLR's personality routine passes these in rdx/edx, not rax/eax.

Make getExceptionPointerRegister a virtual method parameterized by
personality function to allow making this distinction.

Similarly make getExceptionSelectorRegister a virtual method parameterized
by personality function, for symmetry.


Reviewers: pgavlin, majnemer, rnk

Subscribers: jyknight, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D14344

llvm-svn: 252383
2015-11-07 01:11:31 +00:00
NAKAMURA Takumi 9947cacebf Revert r252249 (and r252255, r252258), "[WinEH] Clone funclets with multiple parents"
It behaved flaky due to iterating pointer key values on std::set and std::map.

llvm-svn: 252279
2015-11-06 10:07:33 +00:00
Andrew Kaylor f05a87dff3 Temporarily disable flaky checks in wineh-multi-parent-cloning.
llvm-svn: 252258
2015-11-06 01:15:04 +00:00
Andrew Kaylor 29cd576554 [WinEH] Clone funclets with multiple parents
Windows EH funclets need to always return to a single parent funclet.  However, it is possible for earlier optimizations to combine funclets (probably based on one funclet having an unreachable terminator) in such a way that this condition is violated.

These changes add code to the WinEHPrepare pass to detect situations where a funclet has multiple parents and clone such funclets, fixing up the unwind and catch return edges so that each copy of the funclet returns to the correct parent funclet.

Differential Revision: http://reviews.llvm.org/D13274?id=39098

llvm-svn: 252249
2015-11-06 00:20:50 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.

This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.

Since this is an IR change, a bitcode upgrade has been provided.

Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.

Differential Revision: http://reviews.llvm.org/D14265

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Joseph Tremoulet 6afccf6120 [WinEH] Fix establisher param reg in CLR funclets
Summary:
The CLR's personality routine passes the pointer to the establisher frame
in RCX, not RDX.

Reviewers: pgavlin, majnemer, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14343

llvm-svn: 252135
2015-11-05 02:20:07 +00:00
Joseph Tremoulet 55b51e9dcc [WinEH] Fix eh.exceptionpointer intrinsic lowering
Summary:
Some shared code for handling eh.exceptionpointer and eh.exceptioncode
needs to not share the part that truncates to 32 bits, which is intended
just for exception codes.

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13747

llvm-svn: 250588
2015-10-17 00:08:08 +00:00
Joseph Tremoulet 53e9cbd95a [WinEH] Fix endpad coloring/numbering
Summary:
When a cleanup's cleanupendpad or cleanupret targets a catchendpad, stop
trying to propagate the cleanup's parent's color to the catchendpad, since
what's needed is the cleanup's grandparent's color and the catchendpad
will get that color from the catchpad linkage already.  We already had
this exclusion for invokes, but were missing it for
cleanupendpad/cleanupret.

Also add a missing line that tags cleanupendpads' states in the
EHPadStateMap, without with lowering invokes that target cleanupendpads
which unwind to other handlers (and so don't have the -1 state) will fail.

This fixes the reduced IR repro in PR25163.


Reviewers: majnemer, andrew.w.kaylor, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13797

llvm-svn: 250534
2015-10-16 18:08:16 +00:00
Joseph Tremoulet 28c89bbb36 [WinEH] Add CoreCLR EH table emission
Summary:
Emit the handler and clause locations immediately after the standard
xdata.
Clauses are emitted in the same order and format used to communiate them
to the CLR Execution Engine.
Add a lit test to verify correct table generation on a small but
interesting example function.

Reviewers: majnemer, andrew.w.kaylor, rnk

Subscribers: pgavlin, AndyAyers, llvm-commits

Differential Revision: http://reviews.llvm.org/D13451

llvm-svn: 250219
2015-10-13 20:18:27 +00:00
Reid Kleckner 14e773500e [WinEH] Delete the old landingpad implementation of Windows EH
The new implementation works at least as well as the old implementation
did.

Also delete the associated preparation tests. They don't exercise
interesting corner cases of the new implementation. All the codegen
tests of the EH tables have already been ported.

llvm-svn: 249918
2015-10-09 23:34:53 +00:00
Joseph Tremoulet 676e5cf07f [WinEH] Fix cleanup state numbering
Summary:
 - Recurse from cleanupendpads to their cleanuppads, to make sure the
   cleanuppad is visited if it has a cleanupendpad but no cleanupret.
 - Check for and avoid double-processing cleanuppads, to allow for them to
   have multiple cleanuprets (plus cleanupendpads).
 - Update Cxx state numbering to visit toplevel cleanupendpads and to
   recurse from cleanupendpads to their preds, to ensure we number any
   funclets in inlined cleanups.  SEH state numbering already did this.

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13374

llvm-svn: 249792
2015-10-09 00:46:08 +00:00
David Majnemer c289c9ff55 [WinEH] Remove unreachable blocks before preparation
We remove unreachable blocks because it is pointless to consider them
for coloring.  However, we still had stale pointers to these blocks in
some data structures after we removed them from the function.

Instead, remove the unreachable blocks before attempting to do anything
with the function.

This fixes PR25099.

llvm-svn: 249617
2015-10-07 21:08:25 +00:00
Joseph Tremoulet 39234fc67e [WinEH] Set NoModuleLevelChanges in clone flags
Summary:
This is necessary to keep the cloner from making bogus copies of debug
metadata attached to the IR it is cloning.
Also, avoid running RemapInstruction over all instructions in the common
case that no cloning was performed.

Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13514

llvm-svn: 249591
2015-10-07 19:29:56 +00:00
Reid Kleckner 72ba70418f [SEH] Add llvm.eh.exceptioncode intrinsic
This will support the Clang __exception_code intrinsic.

llvm-svn: 249492
2015-10-07 00:27:33 +00:00
David Majnemer a80c151286 [WinEH] Teach AsmPrinter about funclets
Summary:
Funclets have been turned into functions by the time they hit the object
file.  Make sure that they have decent names for the symbol table and
CFI directives explaining how to reason about their prologues.

Differential Revision: http://reviews.llvm.org/D13261

llvm-svn: 248824
2015-09-29 20:12:33 +00:00
Joseph Tremoulet 09af67aba5 [EH] Create removeUnwindEdge utility
Summary:
Factor the code that rewrites invokes to calls and rewrites WinEH
terminators to their "unwind to caller" equivalents into a helper in
Utils/Local, and use it in the three places I'm aware of that need to do
this.


Reviewers: andrew.w.kaylor, majnemer, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13152

llvm-svn: 248677
2015-09-27 01:47:46 +00:00
Reid Kleckner 813f1b65bc [WinEH] Rip out the landingpad-based C++ EH state numbering code
It never really worked, and the new code is working better every day.

llvm-svn: 247860
2015-09-16 22:14:46 +00:00
David Majnemer 67bff0d88b [WinEHPrepare] Turn terminatepad into a cleanuppad + call + cleanupret
The MSVC doesn't really support exception specifications so let's just
turn these into cleanuppads.  Later, we might use terminatepad to more
efficiently encode the "noexcept"-ness of a function body.

llvm-svn: 247848
2015-09-16 20:42:16 +00:00
Reid Kleckner b005d281c3 [WinEH] Pull Adjectives and CatchObj out of the catchpad arg list
Clang now passes the adjectives as an argument to catchpad.

Getting the CatchObj working is simply a matter of threading another
static alloca through codegen, first as an alloca, then as a frame
index, and finally as a frame offset.

llvm-svn: 247844
2015-09-16 20:16:27 +00:00
David Majnemer 459a64aed7 [WinEHPrepare] Provide a cloning mode which doesn't demote
We are experimenting with a new approach to saving and restoring SSA
values used across funclets: let the register allocator do the dirty
work for us.

However, this means that we need to be able to clone commoned blocks
without relying on demotion.

llvm-svn: 247835
2015-09-16 18:40:37 +00:00
Reid Kleckner 84ebff4a5e [WinEH] Skip state numbering when no EH pads are present
Otherwise we'd try to emit the thunk that passes the LSDA to
__CxxFrameHandler3. We don't emit the LSDA if there were no landingpads,
so we'd end up with an assembler error when trying to write the COFF
object.

llvm-svn: 247820
2015-09-16 17:19:44 +00:00
Reid Kleckner 5dbee7baef [IR] Print the label operands of a catchpad like an invoke
The rest of the EH pads are fine, since they have at most one label and
take fewer operands for the personality.

Old catchpad vs. new:
  %5 = catchpad [i8* bitcast (i32 ()* @"\01?filt$0@0@main@@" to i8*)] to label %__except.ret.10 unwind label %catchendblock.9
-----
  %5 = catchpad [i8* bitcast (i32 ()* @"\01?filt$0@0@main@@" to i8*)]
          to label %__except.ret.10 unwind label %catchendblock.9

llvm-svn: 247433
2015-09-11 17:27:52 +00:00
Joseph Tremoulet f3aff31401 [WinEH] Fix single-block cleanup coloring
Summary:
The coloring code in WinEHPrepare queues cleanuprets' successors with the
correct color (the parent one) when it sees their cleanuppad, and so later
when iterating successors knows to skip processing cleanuprets since
they've already been queued.  This latter check was incorrectly under an
'else' condition and so inadvertently was not kicking in for single-block
cleanups.  This change sinks the check out of the 'else' to fix the bug.

Reviewers: majnemer, andrew.w.kaylor, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12751

llvm-svn: 247299
2015-09-10 16:51:25 +00:00
Joseph Tremoulet 61efbc32a6 [WinEH] Add llvm.eh.exceptionpointer intrinsic
Summary:
This intrinsic can be used to extract a pointer to the exception caught by
a given catchpad.  Its argument has token type and must be a `catchpad`.

Also clarify ExtendingLLVM documentation regarding overloaded intrinsics.


Reviewers: majnemer, andrew.w.kaylor, sanjoy, rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12533

llvm-svn: 246752
2015-09-03 09:15:32 +00:00
Hans Wennborg 4a61370b8f Fix CHECK directives that weren't checking.
llvm-svn: 246485
2015-08-31 21:10:35 +00:00
Joseph Tremoulet ec18285b91 [WinEH] Update coloring to handle nested cases cleanly
Summary:
Change the coloring algorithm in WinEHPrepare to visit a funclet's exits
in its parents' contexts and so properly classify the continuations of
nested funclets.

Also change the placement of cloned blocks to be deterministic and to
maintain the relative order of each funclet's blocks.

Add a lit test showing various patterns that require cloning, the last
several of which don't have CHECKs yet because they require cloning
entire funclets which is NYI.


Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12353

llvm-svn: 246245
2015-08-28 01:12:35 +00:00
Joseph Tremoulet 8220bcc570 [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 0ad363eebc [WinEH] Calculate state numbers for the new EH representation
State numbers are calculated by performing a walk from the innermost
funclet to the outermost funclet.   Rudimentary support for the new EH
constructs has been added to the assembly printer, just enough to test
the new machinery.

Differential Revision: http://reviews.llvm.org/D12098

llvm-svn: 245331
2015-08-18 19:07:12 +00:00
David Majnemer 83f4bb23c4 [WinEHPrepare] Replace unreasonable funclet terminators with unreachable
It is possible to be in a situation where more than one funclet token is
a valid SSA value.  If we see a terminator which exits a funclet which
doesn't use the funclet's token, replace it with unreachable.

Differential Revision: http://reviews.llvm.org/D12074

llvm-svn: 245238
2015-08-17 20:56:39 +00:00