If a local_unnamed_addr attribute is attached to a global, the address
is known to be insignificant within the module. It is distinct from the
existing unnamed_addr attribute in that it only describes a local property
of the module rather than a global property of the symbol.
This attribute is intended to be used by the code generator and LTO to allow
the linker to decide whether the global needs to be in the symbol table. It is
possible to exclude a global from the symbol table if three things are true:
- This attribute is present on every instance of the global (which means that
the normal rule that the global must have a unique address can be broken without
being observable by the program by performing comparisons against the global's
address)
- The global has linkonce_odr linkage (which means that each linkage unit must have
its own copy of the global if it requires one, and the copy in each linkage unit
must be the same)
- It is a constant or a function (which means that the program cannot observe that
the unique-address rule has been broken by writing to the global)
Although this attribute could in principle be computed from the module
contents, LTO clients (i.e. linkers) will normally need to be able to compute
this property as part of symbol resolution, and it would be inefficient to
materialize every module just to compute it.
See:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160509/356401.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160516/356738.html
for earlier discussion.
Part of the fix for PR27553.
Differential Revision: http://reviews.llvm.org/D20348
llvm-svn: 272709
This patch adds an IR, assembly and bitcode representation for metadata
attachments for globals. Future patches will port existing features to use
these new attachments.
Differential Revision: http://reviews.llvm.org/D20074
llvm-svn: 271348
Removed some unused headers, replaced some headers with forward class declarations.
Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'
Patch by Eugene Kosov <claprix@yandex.ru>
Differential Revision: http://reviews.llvm.org/D19219
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
`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
This reverts commit r264869. I am seeing Windows bot failures due to the
"\" in the path being mishandled at some point (seems to be interpreted
wrongly at some point and llvm-as | llvm-dis is yielding some junk
characters). Need to investigate.
llvm-svn: 264871
Summary:
This change serializes out and in the SourceFileName to LLVM assembly
so that it is preserved through "llvm-dis | llvm-as". This is
necessary to ensure that the global identifiers created for local values
in the module summary index are the same even if the bitcode is
streamed out and read back from LLVM assembly.
Serializing the summary itself to LLVM assembly is in progress.
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D18588
llvm-svn: 264869
Without actually parsing a type it is difficult to perdict where
the type definition ends. In other words, instead of expecting
the user of the parser API to hand over only the relevant bits
of the string being parsed, take the whole string, parse the type,
and get back the number of characters that have been read.
This will be used by the MIR testing infrastructure.
llvm-svn: 262884
This is useful for MIR serialization. Indeed generic machine instructions
must have a type and we don't want to duplicate the logic in the MIParser.
llvm-svn: 262868
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
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
When working with tokens, it is often the case that one has instructions
which consume a token and produce a new token. Currently, we have no
mechanism to represent an initial token state.
Instead, we can create a notional "empty token" by inventing a new
constant which captures the semantics we would like. This new constant
is called ConstantTokenNone and is written textually as "token none".
Differential Revision: http://reviews.llvm.org/D14581
llvm-svn: 252811
Summary:
This also adds the first set of tests for operand bundles.
The optimizer has not been audited to ensure that it does the right
thing with operand bundles.
Depends on D12456.
Reviewers: reames, chandlerc, majnemer, dexonsmith, kmod, JosephTremoulet, rnk, bogner
Subscribers: maksfb, llvm-commits
Differential Revision: http://reviews.llvm.org/D12457
llvm-svn: 248551
Summary:
Fixes bug 24645. Problem appears to be that the type may be undefined
when ConvertValIDToValue is called.
Reviewers: kcc
Subscribers: llvm-commits
llvm-svn: 246779
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
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
This commit extends the 'SlotMapping' structure and includes mappings for named
and numbered types in it. The LLParser is extended accordingly to fill out
those mappings at the end of module parsing.
This information is useful when we want to parse standalone constant values
at a later stage using the 'parseConstantValue' method. The constant values
can be constant expressions, which can contain references to types. In order
to parse such constant values, we have to restore the internal named and
numbered mappings for the types in LLParser, otherwise the parser will report
a parsing error. Therefore, this commit also introduces a new method called
'restoreParsingState' to LLParser, which uses the slot mappings to restore
some of its internal parsing state.
This commit is required to serialize constant value pointers in the machine
memory operands for the MIR format.
Reviewers: Duncan P. N. Exon Smith
llvm-svn: 245740
This reverts commit r243888, recommitting r243824.
This broke the Windows build due to a difference in the C++ standard
library implementation. Using emplace/forward_as_tuple should ensure
there's no need to copy ValIDs.
llvm-svn: 243896
* generate function with string attribute using API,
* dump it in LL format,
* try to parse.
Add parser support for string attributes to fix the issue.
Reviewed By: reames, hfinkel
Differential Revision: http://reviews.llvm.org/D11058
llvm-svn: 243877
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
When parsing calls to inline asm the pointee type (of the pointer type
representing the value type of the InlineAsm value) was used. To avoid
using it, use the ValID structure to ferry the FunctionType directly
through to the InlineAsm construction.
This is a bit of a workaround - alternatively the inline asm could
explicitly describe the type but that'd be verbose/redundant in the IR
and so long as the inline asm calls directly in the context of a call or
invoke, this should suffice.
llvm-svn: 243349
This commit extends the interface provided by the AsmParser library by adding a
function that allows the user to parse a standalone contant value.
This change is useful for MIR serialization, as it will allow the MIR Parser to
parse the constant values in a machine constant pool.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10280
llvm-svn: 242579
Summary:
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.
Reviewers: rnk, JosephTremoulet, reames, nlewycky, rjmccall
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11041
llvm-svn: 241888
This commit creates a new structure called 'SlotMapping' in the AsmParser library.
This structure can be passed into the public parsing APIs from the AsmParser library
in order to extract the data structures that map from slot numbers to unnamed global
values and metadata nodes.
This change is useful for MIR Serialization, as the MIR Parser has to lookup the
unnamed global values and metadata nodes by their slot numbers.
Reviewers: Duncan P. N. Exon Smith
Differential Revision: http://reviews.llvm.org/D10551
llvm-svn: 240427
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
Add serialization support for function metadata attachments (added in
r235783). The syntax is:
define @foo() !attach !0 {
Metadata attachments are only allowed on functions with bodies. Since
they come before the `{`, they're not really part of the body; since
they require a body, they're not really part of the header. In
`LLParser` I gave them a separate function called from `ParseDefine()`,
`ParseOptionalFunctionMetadata()`.
In bitcode, I'm using the same `METADATA_ATTACHMENT` record used by
instructions. Instruction metadata attachments are included in a
special "attachment" block at the end of a `Function`. The attachment
records are laid out like this:
InstID (KindID MetadataID)+
Note that these records always have an odd number of fields. The new
code takes advantage of this to recognize function attachments (which
don't need an instruction ID):
(KindID MetadataID)+
This means we can use the same attachment block already used for
instructions.
This is part of PR23340.
llvm-svn: 235785
Remove unused `PFS` variable and take the `Instruction` by reference.
(Not really related to PR23340, but might as well clean this up while
I'm here.)
llvm-svn: 235782
Summary:
If a pointer is marked as dereferenceable_or_null(N), LLVM assumes it
is either `null` or `dereferenceable(N)` or both. This change only
introduces the attribute and adds a token test case for the `llvm-as`
/ `llvm-dis`. It does not hook up other parts of the optimizer to
actually exploit the attribute -- those changes will come later.
For pointers in address space 0, `dereferenceable(N)` is now exactly
equivalent to `dereferenceable_or_null(N)` && `nonnull`. For other
address spaces, `dereferenceable(N)` is potentially weaker than
`dereferenceable_or_null(N)` && `nonnull` (since we could have a null
`dereferenceable(N)` pointer).
The motivating case for this change is Java (and other managed
languages), where pointers are either `null` or dereferenceable up to
some usually known-at-compile-time constant offset.
Reviewers: rafael, hfinkel
Reviewed By: hfinkel
Subscribers: nicholas, llvm-commits
Differential Revision: http://reviews.llvm.org/D8650
llvm-svn: 235132
This reverts r231200 and r231204. The second one added an explicit move
ctor for MSVC.
This change broke the clang-cl self-host due to weirdness in MSVC's
implementation of std::map::insert. Somehow we lost our rvalue ref-ness
when going through variadic placement new:
template <class _Objty, class... _Types>
void construct(_Objty *_Ptr,
_Types &&... _Args) { // construct _Objty(_Types...) at _Ptr
::new ((void *)_Ptr) _Objty(_STD forward<_Types>(_Args)...);
}
For some reason, Clang decided to call the deleted std::pair copy
constructor at this point. Needs further investigation, once I can
build.
llvm-svn: 231269
Accidentally committed a few more of these cleanup changes than
intended. Still breaking these out & tidying them up.
This reverts commit r231135.
llvm-svn: 231136
There doesn't seem to be any need to assert that iterator assignment is
between iterators over the same node - if you want to reuse an iterator
variable to iterate another node, that's perfectly acceptable. Just
don't mix comparisons between iterators into disjoint sequences, as
usual.
llvm-svn: 231135
Move all the types of `MDField` to an anonymous namespace in the source
file. This also eliminates the duplication of `ParseMDField()`
declarations in the header for each new field type.
llvm-svn: 228211
Peter Collingbourne