Summary: Deprecate the existing accessors for the "current debug location" of an IRBuilder. The setter could not handle being reset to NULL, and the getter would create bogus metadata if the NULL location was returned. Provide direct metadata-based accessors instead.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60484
llvm-svn: 358039
Summary:
Now that we can create standalone basic blocks, it's useful to be able to append them. Add bindings to
- Insert a basic block after the current insertion block
- Append a basic block to the end of a function's list of basic blocks
Reviewers: whitequark, deadalnix, harlanhaskins
Reviewed By: whitequark, harlanhaskins
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59658
llvm-svn: 357812
Summary: Add a binding to Function::lookupIntrinsicID so clients don't have to go searching the ID table themselves.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59697
llvm-svn: 356948
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html
This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.
This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.
There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.
Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii
Differential Revision: https://reviews.llvm.org/D53765
llvm-svn: 353563
Summary:
Adds the standard gauntlet of accessors for global indirect functions and updates the echo test.
Now it would be nice to have a target abstraction so one could know if they have access to a suitable ELF linker and runtime.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56177
llvm-svn: 353193
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
consistently accept a pointee-type argument.
Note: this also adds a new C API and soft-deprecates the old C API.
Differential Revision: https://reviews.llvm.org/D56559
llvm-svn: 351124
accept a return-type argument.
Note: this also adds a new C API and soft-deprecates the old C API.
Differential Revision: https://reviews.llvm.org/D56558
llvm-svn: 351123
accept a callee-type argument.
Note: this also adds a new C API and soft-deprecates the old C API.
Differential Revision: https://reviews.llvm.org/D56557
llvm-svn: 351122
accept a callee-type argument.
Note: this also adds a new C API and soft-deprecates the old C API.
Differential Revision: https://reviews.llvm.org/D56556
llvm-svn: 351121
Normally, changing the function signatures of C APIs is disallowed,
but as these two are brand new last week, and haven't been released
yet, it is okay in this instance.
As per discussion in D56556, we will not add NameLen arguments to IR
building APIs, for the following reasons:
1. We do not want to deprecate all of the IR building APIs, just to add a
NameLen argument to each one.
2. Consistency is important, so adding it just to new ones is unfortunate.
3. The IR names are completely optional, useful for readability of IR
only. There is no value in ever supporting nul bytes.
Differential Revision: https://reviews.llvm.org/D56669
llvm-svn: 351076
Summary: Add a utility function for creating a basic block without a parent function. A useful operation for compilers that need to synthesize and conditionally insert code without having to bother with appending and immediately unlinking a block.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56279
llvm-svn: 350608
Summary: Fix an old outstanding problem with the int cast builder binding always assuming the cast is signed by introducing a new LLVMBuildIntCast2 operation and deprecating the old prototype.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56280
llvm-svn: 350607
Summary: Add accessors so the performance improvement from this setting is accessible to third parties.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56179
llvm-svn: 350196
The IEEE-754 Standard makes it clear that fneg(x) and
fsub(-0.0, x) are two different operations. The former is a bitwise
operation, while the latter is an arithmetic operation. This patch
creates a dedicated FNeg IR Instruction to model that behavior.
Differential Revision: https://reviews.llvm.org/D53877
llvm-svn: 346774
Summary:
Improve the intrinsic bindings with operations for
- Retrieving and automatically inserting the declaration of an intrinsic by ID
- Retrieving the name of a non-overloaded intrinsic by ID
- Retrieving the name of an overloaded intrinsic by ID and overloaded parameter types
Improve the echo test to copy non-overloaded intrinsics by ID.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53626
llvm-svn: 346195
This updates the C API for the removal of `TerminatorInst`. It converts
the type query to a predicate query and moves the generic methods to
work on `Instruction` instances that satisfy this predicate rather than
requiring a specific type. It also clarifies that the C API wrapping
`BasicBlock::getTerminator` just returns an `Instruction`. Because this
was always wrapped opaquely as a value and the functions consuming these
values will work on `Instruction` objects, this shouldn't break any
clients.
This is a completely compatible change to the C API.
Differential Revision: https://reviews.llvm.org/D52968
llvm-svn: 344764
Add thin shims to C interface to provide access to DebugLoc info for
Instructions, GlobalVariables and Functions. Patch by Josh Berdine!
llvm-svn: 344202
Summary: Before this, there was no reasonable way to retrieve the type of a global value (most notably, a function) that was created with the C API.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D52659
llvm-svn: 343363
Summary: Adds missing debug information accessors to GlobalObject. This puts the finishing touches on cloning debug info in the echo tests.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: aprantl, JDevlieghere, llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D51522
llvm-svn: 343330
Summary:
This patch adds LLVMIsLiteralStruct to the C API to expose
StructType::isLiteral. This is then used to implement the analogous
addition to the OCaml API.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D52209
llvm-svn: 342435
Summary:
The GlobalIFunc value kind has not yet been added to the OCaml
API. This patch only extends the enum, so that e.g. classify_value
will not crash. No support for manipulating or building GlobalIFuncs
is added at this point.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D52198
llvm-svn: 342429
Summary: Add a new type for named metadata nodes. Use this to implement iterators and accessors for NamedMDNodes and extend the echo test to use them to copy module-level debug information.
Reviewers: whitequark, deadalnix, aprantl, dexonsmith
Reviewed By: whitequark
Subscribers: Wallbraker, JDevlieghere, llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D47179
llvm-svn: 341085
In the past, DbgInfoIntrinsic has a strong assumption that these
intrinsics all have variables and expressions attached to them.
However, it is too strong to derive the class for other debug entities.
Now, it has problems for debug labels.
In order to make DbgInfoIntrinsic as a base class for 'debug info', I
create a class for 'variable debug info', DbgVariableIntrinsic.
DbgDeclareInst, DbgAddrIntrinsic, and DbgValueInst will be derived from it.
Differential Revision: https://reviews.llvm.org/D50220
llvm-svn: 338984
Summary: Add wrappers for a module's alias iterators and a getter and setter for the aliasee value.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D46808
llvm-svn: 332826
Summary:
- Provide LLVMGetValueName2 and LLVMSetValueName2 that return and take the length of the provided C string respectively
- Deprecate LLVMGetValueName and LLVMSetValueName
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D46890
llvm-svn: 332810
Summary:
The first foray into merging debug info into the echo tests.
- Add bindings to Module::getModuleFlagsMetadata() in the form of LLVMCopyModuleFlagsMetadata
- Add the opaque type LLVMModuleFlagEntry to represent Module::ModuleFlagEntry
- Add accessors for LLVMModuleFlagEntry's behavior, key, and metadata node.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: aprantl, JDevlieghere, llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D46792
llvm-svn: 332219
Summary:
- Add a missing getter for module-level inline assembly
- Add a missing append function for module-level inline assembly
- Deprecate LLVMSetModuleInlineAsm and replace it with LLVMSetModuleInlineAsm2 which takes an explicit length parameter
- Deprecate LLVMConstInlineAsm and replace it with LLVMGetInlineAsm, a function that allows passing a dialect and is not mis-classified as a constant operation
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45346
llvm-svn: 329369
Summary:
Previous revision caused a leak in the echo test that got caught by the ASAN bots because of missing free of the handlers array and was reverted in r328759. Resubmitting the patch with that correction.
Add support for cleanupret, catchret, catchpad, cleanuppad and catchswitch and their associated accessors.
Test is modified from SimplifyCFG because it contains many diverse usages of these instructions.
Reviewers: whitequark, deadalnix
Reviewed By: whitequark
Subscribers: llvm-commits, vlad.tsyrklevich
Differential Revision: https://reviews.llvm.org/D45100
llvm-svn: 328883
Summary:
Add support for cleanupret, catchret, catchpad, cleanuppad and catchswitch and their associated accessors.
Test is modified from SimplifyCFG because it contains many diverse usages of these instructions.
Reviewers: whitequark, deadalnix, echristo
Reviewed By: echristo
Subscribers: llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D44496
llvm-svn: 328759
Summary:
The old bindings should have used an enum instead of a boolean. This
deprecates LLVMHasUnnamedAddr and LLVMSetUnnamedAddr , replacing them
with LLVMGetUnnamedAddress and LLVMSetUnnamedAddress respectively that do.
Though it is unlikely LLVM will gain more supported global value linker
hints, the new API can scale to accommodate this.
Reviewers: deadalnix, whitequark
Reviewed By: whitequark
Subscribers: llvm-commits, harlanhaskins
Differential Revision: https://reviews.llvm.org/D43448
llvm-svn: 327479
Patch by Robert Widmann.
Expose getters for MetadataType and TokenType publicly in the C API.
Discovered a need for these while trying to wrap the intrinsics API.
Differential Revision: https://reviews.llvm.org/D38809
llvm-svn: 316762
The C functions added are LLVMGetNumContainedTypes and
LLVMGetSubtypes.
The OCaml function added is Llvm.subtypes.
Patch by Ekaterina Vaartis.
Differential Revision: https://reviews.llvm.org/D33677
llvm-svn: 304709
Summary:
This seems like an uncontroversial first step toward providing access to the metadata hierarchy that now exists in LLVM. This should allow for good debug info support from C.
Future plans are to deprecate API that take mixed bags of values and metadata (mainly the LLVMMDNode family of functions) and migrate the rest toward the use of LLVMMetadataRef.
Once this is in place, mapping of DIBuilder will be able to start.
Reviewers: mehdi_amini, echristo, whitequark, jketema, Wallbraker
Reviewed By: Wallbraker
Subscribers: Eugene.Zelenko, axw, mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D19448
llvm-svn: 300447
Summary:
This kill various depreacated API related to attribute :
- The deprecated C API attribute based on LLVMAttribute enum.
- The Raw attribute set format (planned to be removed in 4.0).
Reviewers: bkramer, echristo, mehdi_amini, void
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D23039
llvm-svn: 286062
Summary:
These are analog to the existing LLVMConstExactSDiv and LLVMBuildExactSDiv
functions.
Reviewers: deadalnix, majnemer
Subscribers: majnemer, llvm-commits
Differential Revision: https://reviews.llvm.org/D25259
llvm-svn: 283269
Summary: As per title. This completes the C API Attribute support.
Reviewers: Wallbraker, whitequark, echristo, rafael, jyknight
Subscribers: mehdi_amini
Differential Revision: http://reviews.llvm.org/D21365
llvm-svn: 272811
Summary: This also deprecated the get attribute function familly.
Reviewers: Wallbraker, whitequark, joker.eph, echristo, rafael, jyknight
Subscribers: axw, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D19181
llvm-svn: 272504
Summary: This needs to get in before anything is released concerning attribute. If the old name gets in the wild, then we are stuck with it forever. Putting it in its own diff should getting that part at least in fast.
Reviewers: Wallbraker, whitequark, joker.eph, echristo, rafael, jyknight
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D20417
llvm-svn: 270452
Summary:
LLVMAttribute has outlived its utility and is becoming a problem for C API users that what to use all the LLVM attributes. In order to help moving away from LLVMAttribute in a smooth manner, this diff introduce LLVMGetAttrKindIDInContext, which can be used instead of the enum values.
See D18749 for reference.
Reviewers: Wallbraker, whitequark, joker.eph, echristo, rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D19081
llvm-svn: 266842
Summary: LLVMAttribute has outlived its utility and is becoming a problem for C API users that what to use all the LLVM attributes. In order to help moving away from LLVMAttribute in a smooth manner, this diff introduce LLVMGetAttrKindIDInContext, which can be used instead of the enum values.
Reviewers: Wallbraker, whitequark, joker.eph, echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18749
llvm-svn: 266257
This patch add support for GCC attribute((ifunc("resolver"))) for
targets that use ELF as object file format. In general ifunc is a
special kind of function alias with type @gnu_indirect_function. Patch
for Clang http://reviews.llvm.org/D15524
Differential Revision: http://reviews.llvm.org/D15525
llvm-svn: 265667
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
Summary: Also expose getters and setters in the C API, so that the change can be tested.
Reviewers: nhaehnle, axw, joker.eph
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D18260
From: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
llvm-svn: 263886
Summary: As per title. There was a lot of part missing in the C API, so I had to extend the invoke and landingpad API.
Reviewers: echristo, joker.eph, Wallbraker
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D17359
llvm-svn: 261254
Summary: The name is confusing as it matche another method on the module.
Reviewers: joker.eph, Wallbraker, echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D17283
llvm-svn: 260920
Summary: This required to add binding to Instruction::removeFromParent so that instruction can be forward declared and then moved at the right place.
Reviewers: bogner, chandlerc, echristo, dblaikie, joker.eph, Wallbraker
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D17057
llvm-svn: 260597
Summary: As per title. This also include extra support for insertvalue and extracvalue.
Reviewers: bogner, chandlerc, echristo, dblaikie, joker.eph, Wallbraker
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D17055
llvm-svn: 260335
Summary: As per title. This remove the need to rely on internal knowledge of call and invoke instruction to find called value and argument count.
Reviewers: bogner, chandlerc, echristo, dblaikie, joker.eph, Wallbraker
Differential Revision: http://reviews.llvm.org/D17054
llvm-svn: 260332
Summary: As per title. Also add a facility method to get the name of a basic block from the C API.
Reviewers: bogner, chandlerc, echristo, dblaikie, joker.eph, Wallbraker
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16912
llvm-svn: 260309
Type specific declarations have been moved to Type.h and error handling
routines have been moved to ErrorHandling.h. Both are included in Core.h
so nothing should change for projects directly including the headers,
but transitive dependencies may be affected.
llvm-svn: 255965
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:
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
This introduces the basic functionality to support "token types".
The motivation stems from the need to perform operations on a Value
whose provenance cannot be obscured.
There are several applications for such a type but my immediate
motivation stems from WinEH. Our personality routine enforces a
single-entry - single-exit regime for cleanups. After several rounds of
optimizations, we may be left with a terminator whose "cleanup-entry
block" is not entirely clear because control flow has merged two
cleanups together. We have experimented with using labels as operands
inside of instructions which are not terminators to indicate where we
came from but found that LLVM does not expect such exotic uses of
BasicBlocks.
Instead, we can use this new type to clearly associate the "entry point"
and "exit point" of our cleanup. This is done by having the cleanuppad
yield a Token and consuming it at the cleanupret.
The token type makes it impossible to obscure or otherwise hide the
Value, making it trivial to track the relationship between the two
points.
What is the burden to the optimizer? Well, it turns out we have already
paid down this cost by accepting that there are certain calls that we
are not permitted to duplicate, optimizations have to watch out for
such instructions anyway. There are additional places in the optimizer
that we will probably have to update but early examination has given me
the impression that this will not be heroic.
Differential Revision: http://reviews.llvm.org/D11861
llvm-svn: 245029
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
Bonus change to remove emacs major mode marker from SystemZMachineFunctionInfo.cpp because emacs already knows it's C++ from the extension. Also fix typo "appeary" in AMDGPUMCAsmInfo.h.
llvm-svn: 243585
Revert the changes to the C API LLVMBuildLandingPad that were part of
the personality function move. We now set the personality on the parent
function when the C API attempts to construct a landingpad with a
personality.
This reverts commit r240010.
llvm-svn: 242372
Summary:
The capability was lost with D10429 where the personality function was set at function level rather than landing pad level. Now there is no way to get/set the personality function from the C API. That is a problem.
Note that the whole thing could be avoided by improving the C API testing, as started by D10725
Reviewers: chandlerc, bogner, majnemer, andrew.w.kaylor, rafael, rnk, axw
Subscribers: rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D10946
llvm-svn: 242104
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
any tests and I even don't know how to run the tests. This seems like a
minimal change to make them work again, although I can't really verify
at this point. Additionally, it probably makes sense to propagate the
personality parameter removal further.
llvm-svn: 240010
constants in commented-out part of LLVMAttribute enum. Add tests that verify
that the safestack attribute is only allowed as a function attribute.
llvm-svn: 239772
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
Split `Metadata` away from the `Value` class hierarchy, as part of
PR21532. Assembly and bitcode changes are in the wings, but this is the
bulk of the change for the IR C++ API.
I have a follow-up patch prepared for `clang`. If this breaks other
sub-projects, I apologize in advance :(. Help me compile it on Darwin
I'll try to fix it. FWIW, the errors should be easy to fix, so it may
be simpler to just fix it yourself.
This breaks the build for all metadata-related code that's out-of-tree.
Rest assured the transition is mechanical and the compiler should catch
almost all of the problems.
Here's a quick guide for updating your code:
- `Metadata` is the root of a class hierarchy with three main classes:
`MDNode`, `MDString`, and `ValueAsMetadata`. It is distinct from
the `Value` class hierarchy. It is typeless -- i.e., instances do
*not* have a `Type`.
- `MDNode`'s operands are all `Metadata *` (instead of `Value *`).
- `TrackingVH<MDNode>` and `WeakVH` referring to metadata can be
replaced with `TrackingMDNodeRef` and `TrackingMDRef`, respectively.
If you're referring solely to resolved `MDNode`s -- post graph
construction -- just use `MDNode*`.
- `MDNode` (and the rest of `Metadata`) have only limited support for
`replaceAllUsesWith()`.
As long as an `MDNode` is pointing at a forward declaration -- the
result of `MDNode::getTemporary()` -- it maintains a side map of its
uses and can RAUW itself. Once the forward declarations are fully
resolved RAUW support is dropped on the ground. This means that
uniquing collisions on changing operands cause nodes to become
"distinct". (This already happened fairly commonly, whenever an
operand went to null.)
If you're constructing complex (non self-reference) `MDNode` cycles,
you need to call `MDNode::resolveCycles()` on each node (or on a
top-level node that somehow references all of the nodes). Also,
don't do that. Metadata cycles (and the RAUW machinery needed to
construct them) are expensive.
- An `MDNode` can only refer to a `Constant` through a bridge called
`ConstantAsMetadata` (one of the subclasses of `ValueAsMetadata`).
As a side effect, accessing an operand of an `MDNode` that is known
to be, e.g., `ConstantInt`, takes three steps: first, cast from
`Metadata` to `ConstantAsMetadata`; second, extract the `Constant`;
third, cast down to `ConstantInt`.
The eventual goal is to introduce `MDInt`/`MDFloat`/etc. and have
metadata schema owners transition away from using `Constant`s when
the type isn't important (and they don't care about referring to
`GlobalValue`s).
In the meantime, I've added transitional API to the `mdconst`
namespace that matches semantics with the old code, in order to
avoid adding the error-prone three-step equivalent to every call
site. If your old code was:
MDNode *N = foo();
bar(isa <ConstantInt>(N->getOperand(0)));
baz(cast <ConstantInt>(N->getOperand(1)));
bak(cast_or_null <ConstantInt>(N->getOperand(2)));
bat(dyn_cast <ConstantInt>(N->getOperand(3)));
bay(dyn_cast_or_null<ConstantInt>(N->getOperand(4)));
you can trivially match its semantics with:
MDNode *N = foo();
bar(mdconst::hasa <ConstantInt>(N->getOperand(0)));
baz(mdconst::extract <ConstantInt>(N->getOperand(1)));
bak(mdconst::extract_or_null <ConstantInt>(N->getOperand(2)));
bat(mdconst::dyn_extract <ConstantInt>(N->getOperand(3)));
bay(mdconst::dyn_extract_or_null<ConstantInt>(N->getOperand(4)));
and when you transition your metadata schema to `MDInt`:
MDNode *N = foo();
bar(isa <MDInt>(N->getOperand(0)));
baz(cast <MDInt>(N->getOperand(1)));
bak(cast_or_null <MDInt>(N->getOperand(2)));
bat(dyn_cast <MDInt>(N->getOperand(3)));
bay(dyn_cast_or_null<MDInt>(N->getOperand(4)));
- A `CallInst` -- specifically, intrinsic instructions -- can refer to
metadata through a bridge called `MetadataAsValue`. This is a
subclass of `Value` where `getType()->isMetadataTy()`.
`MetadataAsValue` is the *only* class that can legally refer to a
`LocalAsMetadata`, which is a bridged form of non-`Constant` values
like `Argument` and `Instruction`. It can also refer to any other
`Metadata` subclass.
(I'll break all your testcases in a follow-up commit, when I propagate
this change to assembly.)
llvm-svn: 223802
Sam McCall