Commit Graph

226 Commits

Author SHA1 Message Date
David Majnemer f93082e71a [coroutines] Part 4[ab]: Coroutine Devirtualization: Lower coro.resume and coro.destroy.
This is the forth patch in the coroutine series. CoroEaly pass now lowers coro.resume
and coro.destroy intrinsics by replacing them with an indirect call to an address
returned by coro.subfn.addr intrinsic. This is done so that CGPassManager recognizes
devirtualization when CoroElide replaces a call to coro.subfn.addr with an appropriate
function address.

Patch by Gor Nishanov!

Differential Revision: https://reviews.llvm.org/D22998

llvm-svn: 277765
2016-08-04 20:30:07 +00:00
Sanjoy Das 4babac89cc [Verifier] Add more tests related to non-integral pointers
As suggested by Matt Arsenault in post-commit review.

llvm-svn: 277550
2016-08-02 23:32:53 +00:00
Sanjoy Das 65ec15b095 [Verifier] Improve test coverage for rL277413
As suggest via post-commit review.

llvm-svn: 277414
2016-08-02 03:23:22 +00:00
Sanjoy Das e1129ee64a [Verifier] Disallow illegal ptr<->int casts in ConstantExprs
This should have been a part of rL277085, but I hadn't considered this
case.

llvm-svn: 277413
2016-08-02 02:55:57 +00:00
David Majnemer d1548eaa17 Included test for r277360.
llvm-svn: 277361
2016-08-01 18:07:19 +00:00
Sanjoy Das c6af5ead86 [IR] Introduce a non-integral pointer type
Summary:
This change adds a `ni` specifier in the `datalayout` string to denote
pointers in some given address spaces as "non-integral", and adds some
typing rules around these special pointers.

Reviewers: majnemer, chandlerc, atrick, dberlin, eli.friedman, tstellarAMD, arsenm

Subscribers: arsenm, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D22488

llvm-svn: 277085
2016-07-28 23:43:38 +00:00
Nicolai Haehnle 84c9f9919a Add writeonly IR attribute
Summary:
This complements the earlier addition of IntrWriteMem and IntrWriteArgMem
LLVM intrinsic properties, see D18291.

Also start using the attribute for memset, memcpy, and memmove intrinsics,
and remove their special-casing in BasicAliasAnalysis.

Reviewers: reames, joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18714

llvm-svn: 274485
2016-07-04 08:01:29 +00:00
Matt Arsenault 82f41518ed Verifier: Reject non-float !fpmath
Code already assumes this is float. getFPAccuracy()
crashes on any other type.

llvm-svn: 273912
2016-06-27 19:43:15 +00:00
Artur Pilipenko 1cec4fdddf Upgrade old memset/memcpy signatures (without isVolatile argument) in tests
We no longer have corresponding code in autoupgrade and the vast majority of the tests were fixed long time ago. Fix the remaining few. One of the verifier test cases is marked as XFAIL because it was passing only because the signature was incorrect.

llvm-svn: 273428
2016-06-22 15:16:06 +00:00
Peter Collingbourne 21521891a2 IR: Allow metadata attachments on declarations, and fix lazy loaded metadata issue with globals.
This change is motivated by an upcoming change to the metadata representation
used for CFI. The indirect function call checker needs type information for
external function declarations in order to correctly generate jump table
entries for such declarations. We currently associate such type information
with declarations using a global metadata node, but I plan [1] to move all
such metadata to global object attachments.

In bitcode, metadata attachments for function declarations appear in the
global metadata block. This seems reasonable to me because I expect metadata
attachments on declarations to be uncommon. In the long term I'd also expect
this to be the case for CFI, because we'd want to use some specialized bitcode
format for this metadata that could be read as part of the ThinLTO thin-link
phase, which would mean that it would not appear in the global metadata block.

To solve the lazy loaded metadata issue I was seeing with D20147, I use the
same bitcode representation for metadata attachments for global variables as I
do for function declarations. Since there's a use case for metadata attachments
in the global metadata block, we might as well use that representation for
global variables as well, at least until we have a mechanism for lazy loading
global variables.

In the assembly format, the metadata attachments appear after the "declare"
keyword in order to avoid a parsing ambiguity.

[1] http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html

Differential Revision: http://reviews.llvm.org/D21052

llvm-svn: 273336
2016-06-21 23:42:48 +00:00
Peter Collingbourne 6dbee00d67 Verifier: check that functions have at most a single !prof attachment.
llvm-svn: 272734
2016-06-14 23:13:15 +00:00
Sanjoy Das c2cf6ef8e2 [IR] Disallow loading and storing unsized types
Summary:
It isn't clear what is the operational meaning of loading or storing an
unsized types, since it cannot be lowered into something meaningful.
Since there does not seem to be any practical need for it either, make
such loads and stores illegal IR.

Reviewers: majnemer, chandlerc

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D20846

llvm-svn: 271402
2016-06-01 16:13:10 +00:00
Peter Collingbourne 382d81cacf IR: Allow multiple global metadata attachments with the same type.
This will be necessary to allow the global merge pass to attach
multiple debug info metadata nodes to global variables once we reverse
the edge from DIGlobalVariable to GlobalVariable.

Differential Revision: http://reviews.llvm.org/D20414

llvm-svn: 271358
2016-06-01 01:17:57 +00:00
Sanjoy Das e0aa414acf 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
Adrian Prantl 93035c8f47 Verifier: Verify that each inlinable callsite of a debug-info-bearing function
in a debug-info-bearing function has a debug location attached to it. Failure to
do so causes an "!dbg attachment points at wrong subprogram for function"
assertion failure when the inliner sets up inline scope info.

rdar://problem/25878916

This reaplies r267320 without changes after fixing an issue in the OpenMP IR
generator in clang.

llvm-svn: 267370
2016-04-24 22:23:13 +00:00
Adrian Prantl da99dced5c Revert "Verifier: Verify that each inlinable callsite of a debug-info-bearing function"
This reverts commit r267320 while investigating an OpenMP buildbot failure.

llvm-svn: 267322
2016-04-24 03:47:37 +00:00
Adrian Prantl 971481db98 Verifier: Verify that each inlinable callsite of a debug-info-bearing function
in a debug-info-bearing function has a debug location attached to it. Failure to
do so causes an "!dbg attachment points at wrong subprogram for function"
assertion failure when the inliner sets up inline scope info.

rdar://problem/25878916

llvm-svn: 267320
2016-04-24 03:23:02 +00:00
Duncan P. N. Exon Smith a59d3e5af8 DebugInfo: Remove MDString-based type references
Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*.  It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType.  The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata.  Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

  http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296
2016-04-23 21:08:00 +00:00
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
Davide Italiano 266a665f9f Revert "[IR/Verifier] Each DISubprogram with isDefinition: true must belong to a CU."
This reverts commit r266102. The O(N^2) verifier check causes timeouts
in LTO test suite.

llvm-svn: 266221
2016-04-13 18:08:07 +00:00
Davide Italiano 245383c584 [DebugInfo] Add error message to test.
Suggested by Rafael as post-commit review (r266102).

llvm-svn: 266134
2016-04-12 21:44:16 +00:00
Davide Italiano b390d8ee39 [IR/Verifier] Each DISubprogram with isDefinition: true must belong to a CU.
Add a check to catch violations. ~60 tests were broken and prevented
this change to be committed. Adrian and I (thanks Adrian!) went
through them in the last week or so updating. The check can be
done more efficiently but I'd still like to get this in ASAP to
avoid more broken tests to be checked in (if any).

PR:  27101
llvm-svn: 266102
2016-04-12 18:22:33 +00:00
George Burgess IV 278199f615 Add the allocsize attribute to LLVM.
`allocsize` is a function attribute that allows users to request that
LLVM treat arbitrary functions as allocation functions.

This patch makes LLVM accept the `allocsize` attribute, and makes
`@llvm.objectsize` recognize said attribute.

The review for this was split into two patches for ease of reviewing:
D18974 and D14933. As promised on the revisions, I'm landing both
patches as a single commit.

Differential Revision: http://reviews.llvm.org/D14933

llvm-svn: 266032
2016-04-12 01:05:35 +00:00
Sanjoy Das 5ce3272833 Don't IPO over functions that can be de-refined
Summary:
Fixes PR26774.

If you're aware of the issue, feel free to skip the "Motivation"
section and jump directly to "This patch".

Motivation:

I define "refinement" as discarding behaviors from a program that the
optimizer has license to discard.  So transforming:

```
void f(unsigned x) {
  unsigned t = 5 / x;
  (void)t;
}
```

to

```
void f(unsigned x) { }
```

is refinement, since the behavior went from "if x == 0 then undefined
else nothing" to "nothing" (the optimizer has license to discard
undefined behavior).

Refinement is a fundamental aspect of many mid-level optimizations done
by LLVM.  For instance, transforming `x == (x + 1)` to `false` also
involves refinement since the expression's value went from "if x is
`undef` then { `true` or `false` } else { `false` }" to "`false`" (by
definition, the optimizer has license to fold `undef` to any non-`undef`
value).

Unfortunately, refinement implies that the optimizer cannot assume
that the implementation of a function it can see has all of the
behavior an unoptimized or a differently optimized version of the same
function can have.  This is a problem for functions with comdat
linkage, where a function can be replaced by an unoptimized or a
differently optimized version of the same source level function.

For instance, FunctionAttrs cannot assume a comdat function is
actually `readnone` even if it does not have any loads or stores in
it; since there may have been loads and stores in the "original
function" that were refined out in the currently visible variant, and
at the link step the linker may in fact choose an implementation with
a load or a store.  As an example, consider a function that does two
atomic loads from the same memory location, and writes to memory only
if the two values are not equal.  The optimizer is allowed to refine
this function by first CSE'ing the two loads, and the folding the
comparision to always report that the two values are equal.  Such a
refined variant will look like it is `readonly`.  However, the
unoptimized version of the function can still write to memory (since
the two loads //can// result in different values), and selecting the
unoptimized version at link time will retroactively invalidate
transforms we may have done under the assumption that the function
does not write to memory.

Note: this is not just a problem with atomics or with linking
differently optimized object files.  See PR26774 for more realistic
examples that involved neither.

This patch:

This change introduces a new set of linkage types, predicated as
`GlobalValue::mayBeDerefined` that returns true if the linkage type
allows a function to be replaced by a differently optimized variant at
link time.  It then changes a set of IPO passes to bail out if they see
such a function.

Reviewers: chandlerc, hfinkel, dexonsmith, joker.eph, rnk

Subscribers: mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18634

llvm-svn: 265762
2016-04-08 00:48:30 +00:00
Davide Italiano 08f8f21b91 [IR/Verifier] Fix (yet another) crash.
We need to check that if we reference a retainedType from
DICompileUnit we're actually referencing a DICompositeType.

llvm-svn: 265752
2016-04-08 00:01:32 +00:00
Davide Italiano 5f1c87bf07 [IRVerifier] Don't crash on invalid DIFile inside DISubprogram.
r265515, this time with the correct fix. file inside DISubprogram is not
mandatory.

llvm-svn: 265586
2016-04-06 18:46:39 +00:00
Davide Italiano 22680e1c5c Revert "[IRVerifier] Don't crash on invalid DIFile inside DISubprogram."
This reverts commit r265515 as lots of tests need to be fixed before
this actually can go in.

llvm-svn: 265517
2016-04-06 04:34:38 +00:00
Davide Italiano 2deceb0339 [IRVerifier] Don't crash on invalid DIFile inside DISubprogram.
llvm-svn: 265515
2016-04-06 03:57:47 +00:00
Davide Italiano 8dc23a3cb5 [IRVerifier] Avoid crashing on an invalid compile unit.
llvm-svn: 265514
2016-04-06 03:07:58 +00:00
Manman Ren 9bfd0d03e9 Swift Calling Convention: add swifterror attribute.
A ``swifterror`` attribute can be applied to a function parameter or an
AllocaInst.

This commit does not include any target-specific change. The target-specific
optimization will come as a follow-up patch.

Differential Revision: http://reviews.llvm.org/D18092

llvm-svn: 265189
2016-04-01 21:41:15 +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
Adrian Prantl b939a25707 Move the DebugEmissionKind enum from DIBuilder into DICompileUnit.
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.

http://reviews.llvm.org/D18612
<rdar://problem/25427165>

llvm-svn: 265077
2016-03-31 23:56:58 +00:00
Sanjoy Das 021de058df 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
Manman Ren f46262e0b7 Swift Calling Convention: add swiftself attribute.
Differential Revision: http://reviews.llvm.org/D17866

llvm-svn: 264754
2016-03-29 17:37:21 +00:00
Adrian Prantl faebbb053d Add an IR Verifier check for orphaned DICompileUnits.
A DICompileUnit that is not listed in llvm.dbg.cu will cause assertion
failures and/or crashes in the backend. The Verifier should reject this.

rdar://problem/25369499

llvm-svn: 264657
2016-03-28 21:06:26 +00:00
Michael Kruse ff379b69b2 [Verifier] Reject PHIs using defs from own block.
Reject the following IR as malformed (assuming that %entry, %next are
not in a loop):

    next:
      %y = phi i32 [ 0, %entry ]
      %x = phi i32 [ %y, %entry ]

Such PHI nodes came up in PR26718. While there was no consensus on
whether or not this is valid IR, most opinions on that bug and in a
discussion on the llvm-dev mailing list tended towards a
"strict interpretation" (term by Joseph Tremoulet) of PHI node uses.
Also, the language reference explicitly states that "the use of each
incoming value is deemed to occur on the edge from the corresponding
predecessor block to the current block" and
`DominatorTree::dominates(Instruction*, Use&)` uses this definition as
well.

For the code mentioned in PR15384, clang does not compile to such PHIs
(anymore?). The test case still hangs when replacing `%tmp6` with `%tmp`
in revisions before r176366 (where PR15384 has been fixed). The
occurrence of %tmp6 therefore was probably unintentional. Its value is
not used except in other PHIs.

Reviewers: majnemer, reames, JosephTremoulet, bkramer, grosser, jdoerfert, kparzysz, sanjoy

Differential Revision: http://reviews.llvm.org/D18443

llvm-svn: 264528
2016-03-26 23:32:57 +00:00
Sanjoy Das b51325dbdb 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
David Majnemer 45ebda4278 [Verifier] Don't abort on invalid cleanuprets
Code in visitEHPadPredecessors assume a little too much about the
validity of a cleanupret with an invalid cleanuppad operand.

llvm-svn: 262364
2016-03-01 18:59:50 +00:00
David Majnemer f08579f5a8 [Verifier] Diagnose when unwinding out of cycles of blocks
Generally speaking, this can only happen with unreachable code.
However, neglecting to check for this condition would lead us to loop
forever.

llvm-svn: 262284
2016-03-01 01:19:05 +00:00
David Majnemer fe2f7f367a [Verifier] Handle more funclet edge cases
This change makes the verifier a little more paranoid.  It was possible
to trick the verifier into crashing or infinite looping.

llvm-svn: 262268
2016-02-29 22:56:36 +00:00
Sanjoy Das 999dc75c12 [Verifier] Minor fix to error message; NFC
llvm-svn: 262262
2016-02-29 22:04:25 +00:00
Sanjoy Das a34ce95b60 Add a "gc-transition" operand bundle
Summary:
This adds a new kind of operand bundle to LLVM denoted by the
`"gc-transition"` tag.  Inputs to `"gc-transition"` operand bundle are
lowered into the "transition args" section of `gc.statepoint` by
`RewriteStatepointsForGC`.

This removes the last bit of functionality that was unsupported in the
deopt bundle based code path in `RewriteStatepointsForGC`.

Reviewers: pgavlin, JosephTremoulet, reames

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16342

llvm-svn: 258338
2016-01-20 19:50:25 +00:00
Joseph Tremoulet a9a05cbcf9 [WinEH] Fix catchpad pred verification
Summary:
The code was simply ensuring that the catchpad's pred is its catchswitch,
which was letting cases slip through where the flow edge was the unwind
edge of the catchswitch rather than one of its catch clauses.

Reviewers: andrew.w.kaylor, rnk, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D16011

llvm-svn: 257275
2016-01-10 04:32:03 +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 e28885e693 [WinEH] Verify unwind edges against EH pad tree
Summary:
Funclet EH personalities require a tree-like nesting among funclets
(enforced by the ParentPad linkage in the IR), and also require that
unwind edges conform to certain rules with respect to the tree:
 - An unwind edge may exit 0 or more ancestor pads
 - An unwind edge must enter exactly one EH pad, which must be distinct
   from any exited pads
 - A cleanupret's edge must exit its cleanuppad

Describe these rules in the LangRef, and enforce them in the verifier.


Reviewers: rnk, majnemer, andrew.w.kaylor

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15961

llvm-svn: 257272
2016-01-10 04:28:38 +00:00
Philip Reames 3e2cf5320c [Statepoints] Initial support for relocating vectors of pointers
Currently, we try to split vectors of pointers back into their component pointer elements during rewrite-statepoints-for-gc. This is less than ideal since presumably the vectorizer chose to vectorize for a reason. :) It's also been a source of bugs - in particular, the relocation logic as currently implemented was recently discovered to be wrong.

The alternate approach is to allow gc.relocates of vector-of-pointer type and update the backend to handle them. That's what this patch tries to do. This won't actually enable vector-of-pointers in practice - there are some RS4GC changes needed - but the lowering is standalone and testable so it makes sense to separate.

Note that there are some known cases around vector constants which this patch does not handle. Once this is in, I'll send another patch with individual fixes and test cases. 

Differential Revision: http://reviews.llvm.org/D15632

llvm-svn: 257022
2016-01-07 03:32:11 +00:00
Joseph Tremoulet 131a462690 [WinEH] Verify catchswitch handlers
Summary:
The handler list must be nonempty and consist solely of CatchPads.


Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15842

llvm-svn: 256691
2016-01-02 15:25:25 +00:00
Joseph Tremoulet 06125e52a7 [WinEH] Tighten parentPad verifier checks
Summary: A catchswitch cannot be a parent of a cleanuppad or another catchswitch.

Reviewers: rnk, andrew.w.kaylor, majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D15841

llvm-svn: 256690
2016-01-02 15:24:24 +00:00
Chen Li d71999ef1b [gc.statepoint] Change gc.statepoint intrinsic's return type to token type instead of i32 type
Summary: This patch changes gc.statepoint intrinsic's return type to token type instead of i32 type. Using token types could prevent LLVM to merge different gc.statepoint nodes into PHI nodes and cause further problems with gc relocations. The patch also changes the way on how gc.relocate and gc.result look for their corresponding gc.statepoint on unwind path. The current implementation uses the selector value extracted from a { i8*, i32 } landingpad as a hook to find the gc.statepoint, while the patch directly uses a token type landingpad (http://reviews.llvm.org/D15405) to find the gc.statepoint. 

Reviewers: sanjoy, JosephTremoulet, pgavlin, igor-laevsky, mjacob

Subscribers: reames, mjacob, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D15662

llvm-svn: 256443
2015-12-26 07:54:32 +00:00