266 Commits

Author SHA1 Message Date
Adrian Prantl
56d0100cfa Teach the IR verifier to reject conflicting debug info for function arguments.
Conflicting debug info for function arguments causes hard-to-debug
assertions in the DWARF backend, so the Verifier should reject it.
For performance reasons this only checks function arguments from
non-inlined debug intrinsics for now.

rdar://problem/30520286

This reapplies r295749 after fixing PR32042.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296543 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 23:48:42 +00:00
Dehao Chen
e26c421c66 Add function importing info from samplepgo profile to the module summary.
Summary: For SamplePGO, the profile may contain cross-module inline stacks. As we need to make sure the profile annotation happens when all the hot inline stacks are expanded, we need to pass this info to the module importer so that it can import proper functions if necessary. This patch implemented this feature by emitting cross-module targets as part of function entry metadata. In the module-summary phase, the metadata is used to build call edges that points to functions need to be imported.

Reviewers: mehdi_amini, tejohnson

Reviewed By: tejohnson

Subscribers: davidxl, llvm-commits

Differential Revision: https://reviews.llvm.org/D30053

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296498 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-28 18:09:44 +00:00
Adrian Prantl
84277628a6 Revert "Teach the IR verifier to reject conflicting debug info for function arguments."
This reverts commit r295749 while investigating PR32042.

It looks like this check uncovered a problem in the frontend that
needs to be fixed before the check can be enabled again.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296005 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-23 19:13:48 +00:00
Adrian Prantl
fb2cee97e4 Teach the IR verifier to reject conflicting debug info for function arguments.
Conflicting debug info for function arguments causes hard-to-debug
assertions in the DWARF backend, so the Verifier should reject it.
For performance reasons this only checks function arguments from
non-inlined debug intrinsics for now.

rdar://problem/30520286

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295749 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-21 19:03:15 +00:00
Davide Italiano
3abe103b2e [IR/Verifier] List the CU we weren't able to find in llvm.dbg.cu.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295678 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-20 22:51:42 +00:00
Justin Bogner
a39b1ce61f Verifier: Disallow a line number without a file in DISubprogram
A line number doesn't make much sense if you don't say where it's
from. Add a verifier check for this and update some tests that had
bogus debug info.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295516 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-17 23:57:42 +00:00
Andrew Kaylor
e6f10d3481 Add intrinsics for constrained floating point operations
This commit introduces a set of experimental intrinsics intended to prevent
optimizations that make assumptions about the rounding mode and floating point
exception behavior.  These intrinsics will later be extended to specify
flush-to-zero behavior.  More work is also required to model instruction
dependencies in machine code and to generate these instructions from clang
(when required by pragmas and/or command line options that are not currently
supported).

Differential Revision: https://reviews.llvm.org/D27028



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293226 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-26 23:27:59 +00:00
Sanjoy Das
d9c611c77e [TBAAVerifier] Be stricter around verifying scalar nodes
This fixes the issue exposed in PR31393, where we weren't trying
sufficiently hard to diagnose bad TBAA metadata.

This does reduce the variety in the error messages we print out, but I
think the tradeoff of verifying more, simply and quickly overrules the
need for more helpful error messags here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290713 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-29 15:47:05 +00:00
Igor Laevsky
f755153552 Introduce element-wise atomic memcpy intrinsic
This change adds a new intrinsic which is intended to provide memcpy functionality
with additional atomicity guarantees. Please refer to the review thread
or language reference for further details.

Differential Revision: https://reviews.llvm.org/D27133



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290708 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-29 14:31:07 +00:00
Adrian Prantl
7b500b4bdf [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades and a change
to the Bitcode record for DIGlobalVariable, that makes upgrading the
old format unambiguous also for variables without DIExpressions.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290153 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-20 02:09:43 +00:00
Adrian Prantl
096faa974a Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289920 (again).
I forgot to implement a Bitcode upgrade for the case where a DIGlobalVariable
has not DIExpression. Unfortunately it is not possible to safely upgrade
these variables without adding a flag to the bitcode record indicating which
version they are.
My plan of record is to roll the planned follow-up patch that adds a
unit: field to DIGlobalVariable into this patch before recomitting.
This way we only need one Bitcode upgrade for both changes (with a
version flag in the bitcode record to safely distinguish the record
formats).

Sorry for the churn!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289982 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 19:39:01 +00:00
Mehdi Amini
ce07e02348 Strip invalid TBAA when reading bitcode
This ensures backward compatibility on bitcode loading.

Differential Revision: https://reviews.llvm.org/D27839

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289977 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 19:16:29 +00:00
Adrian Prantl
eb38a2a075 [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

This reapplies r289902 with additional testcase upgrades.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289920 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 04:25:54 +00:00
Adrian Prantl
7766e56d48 Revert "[IR] Remove the DIExpression field from DIGlobalVariable."
This reverts commit 289902 while investigating bot berakage.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289906 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 01:00:30 +00:00
Adrian Prantl
1b11b0778e [IR] Remove the DIExpression field from DIGlobalVariable.
This patch implements PR31013 by introducing a
DIGlobalVariableExpression that holds a pair of DIGlobalVariable and
DIExpression.

Currently, DIGlobalVariables holds a DIExpression. This is not the
best way to model this:

(1) The DIGlobalVariable should describe the source level variable,
    not how to get to its location.

(2) It makes it unsafe/hard to update the expressions when we call
    replaceExpression on the DIGLobalVariable.

(3) It makes it impossible to represent a global variable that is in
    more than one location (e.g., a variable with multiple
    DW_OP_LLVM_fragment-s).  We also moved away from attaching the
    DIExpression to DILocalVariable for the same reasons.

<rdar://problem/29250149>
https://llvm.org/bugs/show_bug.cgi?id=31013
Differential Revision: https://reviews.llvm.org/D26769

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289902 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-16 00:36:43 +00:00
Sanjoy Das
8cf1000f92 [Verifier] Allow TBAA metadata on atomicrmw and atomiccmpxchg
This used to be allowed before r289402 by default (before r289402 you
could have TBAA metadata on any instruction), and while I'm not sure
that it helps, it does sound reasonable enough to not fail the verifier
and we have out-of-tree users who use this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289872 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-15 21:23:44 +00:00
Sanjoy Das
a942d77488 [Verifier] Add verification for TBAA metadata
Summary:
This change adds some verification in the IR verifier around struct path
TBAA metadata.

Other than some basic sanity checks (e.g. we get constant integers where
we expect constant integers), this checks:

 - That by the time an struct access tuple `(base-type, offset)` is
   "reduced" to a scalar base type, the offset is `0`.  For instance, in
   C++ you can't start from, say `("struct-a", 16)`, and end up with
   `("int", 4)` -- by the time the base type is `"int"`, the offset
   better be zero.  In particular, a variant of this invariant is needed
   for `llvm::getMostGenericTBAA` to be correct.

 - That there are no cycles in a struct path.

 - That struct type nodes have their offsets listed in an ascending
   order.

 - That when generating the struct access path, you eventually reach the
   access type listed in the tbaa tag node.

Reviewers: dexonsmith, chandlerc, reames, mehdi_amini, manmanren

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D26438

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289402 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-11 20:07:15 +00:00
Adrian Prantl
3d7360fb8a Verifier: Reject any unknown named MD nodes in the llvm.dbg namespace.
This came out of a discussion in https://reviews.llvm.org/D25285.

There used to be various other llvm.dbg.* nodes, but we don't support
upgrading them and we want to reserve the namespace for future uses.

This also removes an entirely obsolete and bitrotted testcase for PR7662.

Reapplies 283390 with a forgotten testcase.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283400 91177308-0d34-0410-b5e6-96231b3b80d8
2016-10-05 22:15:37 +00:00
David Majnemer
5964d136e5 [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277765 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-04 20:30:07 +00:00
Sanjoy Das
f9a50810e2 [Verifier] Add more tests related to non-integral pointers
As suggested by Matt Arsenault in post-commit review.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277550 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-02 23:32:53 +00:00
Sanjoy Das
f21ab36404 [Verifier] Improve test coverage for rL277413
As suggest via post-commit review.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277414 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-02 03:23:22 +00:00
Sanjoy Das
308cf93891 [Verifier] Disallow illegal ptr<->int casts in ConstantExprs
This should have been a part of rL277085, but I hadn't considered this
case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277413 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-02 02:55:57 +00:00
David Majnemer
c6005fe2b8 Included test for r277360.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277361 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-01 18:07:19 +00:00
Sanjoy Das
1c20b71db8 [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277085 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-28 23:43:38 +00:00
Nicolai Haehnle
b07f540456 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274485 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-04 08:01:29 +00:00
Matt Arsenault
1d88d3b08d Verifier: Reject non-float !fpmath
Code already assumes this is float. getFPAccuracy()
crashes on any other type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273912 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-27 19:43:15 +00:00
Artur Pilipenko
b2b7d8b579 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273428 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-22 15:16:06 +00:00
Peter Collingbourne
99e2e27b37 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273336 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-21 23:42:48 +00:00
Peter Collingbourne
cf9e0af1ce Verifier: check that functions have at most a single !prof attachment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272734 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-14 23:13:15 +00:00
Sanjoy Das
da6ed23fe1 [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271402 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-01 16:13:10 +00:00
Peter Collingbourne
d8d85ac3c9 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271358 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-01 01:17:57 +00:00
Sanjoy Das
d2e75bd7aa 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269261 91177308-0d34-0410-b5e6-96231b3b80d8
2016-05-12 01:17:38 +00:00
Adrian Prantl
c5cc3f2a20 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267370 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-24 22:23:13 +00:00
Adrian Prantl
08290fd4f3 Revert "Verifier: Verify that each inlinable callsite of a debug-info-bearing function"
This reverts commit r267320 while investigating an OpenMP buildbot failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267322 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-24 03:47:37 +00:00
Adrian Prantl
522b700b9b 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267320 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-24 03:23:02 +00:00
Duncan P. N. Exon Smith
de7484036b 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267296 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-23 21:08:00 +00:00
Adrian Prantl
4eeaa0da04 [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>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266446 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-15 15:57:41 +00:00
Davide Italiano
4a1c79f1f4 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266221 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-13 18:08:07 +00:00
Davide Italiano
e6f98f0821 [DebugInfo] Add error message to test.
Suggested by Rafael as post-commit review (r266102).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266134 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-12 21:44:16 +00:00
Davide Italiano
361311da1f [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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266102 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-12 18:22:33 +00:00
George Burgess IV
274105b8b5 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266032 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-12 01:05:35 +00:00
Sanjoy Das
c9e3e3cbfd 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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265762 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-08 00:48:30 +00:00
Davide Italiano
a63892db7c [IR/Verifier] Fix (yet another) crash.
We need to check that if we reference a retainedType from
DICompileUnit we're actually referencing a DICompositeType.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265752 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-08 00:01:32 +00:00
Davide Italiano
fd0bc4ee66 [IRVerifier] Don't crash on invalid DIFile inside DISubprogram.
r265515, this time with the correct fix. file inside DISubprogram is not
mandatory.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265586 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-06 18:46:39 +00:00
Davide Italiano
f504f6f4f7 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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265517 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-06 04:34:38 +00:00
Davide Italiano
ce42332d64 [IRVerifier] Don't crash on invalid DIFile inside DISubprogram.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265515 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-06 03:57:47 +00:00
Davide Italiano
d7975248c1 [IRVerifier] Avoid crashing on an invalid compile unit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265514 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-06 03:07:58 +00:00
Manman Ren
4bda882517 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265189 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-01 21:41:15 +00:00
Adrian Prantl
7876f64bc3 testcase gardening: update the emissionKind enum to the new syntax. (NFC)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265081 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-01 00:16:49 +00:00
Adrian Prantl
39bb84a097 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>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265077 91177308-0d34-0410-b5e6-96231b3b80d8
2016-03-31 23:56:58 +00:00