Commit Graph

366 Commits

Author SHA1 Message Date
Chris Bieneman e49730d4ba Remove autoconf support
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html

"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi

Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark

Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D16471

llvm-svn: 258861
2016-01-26 21:29:08 +00:00
Rafael Espindola 2339ffed97 Deprecate a few C APIs.
This deprecates:
* LLVMParseBitcode
* LLVMParseBitcodeInContext
* LLVMGetBitcodeModuleInContext
* LLVMGetBitcodeModule

They are replaced with the functions with a 2 suffix which do not record
a diagnostic.

llvm-svn: 256065
2015-12-18 23:46:42 +00:00
Eric Christopher a6b96004b5 Reorganize the C API headers to improve build times.
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
2015-12-18 01:46:52 +00:00
Rafael Espindola 434e956181 Change linkInModule to take a std::unique_ptr.
Passing in a std::unique_ptr should help find errors when the module
is used after being linked into another module.

llvm-svn: 255842
2015-12-16 23:16:33 +00:00
Richard Diamond 72303a2436 Fix `llvm-config` to adapt to the install environment.
Summary:
This patch does a couple of things:

  - Adds a new argument `--shared-mode` which accepts a list of components and prints whether or not the provided components need to be linked statically or shared.
  - Fixes `--libnames` when CMake BUILD_SHARED_LIBS is used.
  - Fixes `--libnames`, `--libs`, and `--libfiles` for dylib when static components aren't installed.
  - Fixes `--libnames`, `--libs`, `--libfiles`, and `--components` to use LLVM_DYLIB_COMPONENTS as the component manifest for dylib linking.
  - Uses the host platform's usual convention for filename extensions and such, instead of always defaulting to Unix-izms.

Because I don't own a Mac, I am not able to test the Mac platform dependent stuff locally. If someone would be willing to run a build for me on their machine (unless there's a better option), I'd appreciate it.

Reviewers: jfb, brad.king, whitequark, beanz

Subscribers: beanz, jauhien, llvm-commits

Differential Revision: http://reviews.llvm.org/D13198

llvm-svn: 252532
2015-11-09 23:15:38 +00:00
Peter Collingbourne d4bff30370 DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.

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

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

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

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

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

llvm-svn: 252219
2015-11-05 22:03:56 +00:00
Peter Zotov 45d29670ae [OCaml] Expose Llvm.{set_,}unnamed_addr.
Patch by Jacques-Pascal Deplaix <jp.deplaix@gmail.com>

llvm-svn: 250912
2015-10-21 17:43:02 +00:00
Eric Christopher bdafb3cd1c Remove DIFile from createSubroutineType.
Patch by Amaury Sechet with a small modification by me.

llvm-svn: 250374
2015-10-15 06:56:10 +00:00
Andrew Wilkins df17a9c5a9 [bindings] Update Go bindings to DIBuilder
Summary:
Update the Go bindings to DIBuilder to match
the split of creating local variables into
auto and parameter variables.

Reviewers: pcc

Subscribers: llvm-commits, axw

Differential Revision: http://reviews.llvm.org/D11864

llvm-svn: 246935
2015-09-06 02:22:15 +00:00
Chandler Carruth 7adc3a2b0e [PM/AA] Remove the last relics of the separate IPA library from LLVM,
folding the code into the main Analysis library.

There already wasn't much of a distinction between Analysis and IPA.
A number of the passes in Analysis are actually IPA passes, and there
doesn't seem to be any advantage to separating them.

Moreover, it makes it hard to have interactions between analyses that
are both local and interprocedural. In trying to make the Alias Analysis
infrastructure work with the new pass manager, it becomes particularly
awkward to navigate this split.

I've tried to find all the places where we referenced this, but I may
have missed some. I have also adjusted the C API to continue to be
equivalently functional after this change.

Differential Revision: http://reviews.llvm.org/D12075

llvm-svn: 245318
2015-08-18 17:51:53 +00:00
Richard Diamond 23280472c3 Revert "Fix `llvm-config` to emit the linker flag for the combined shared object built by autoconfig/make instead of the individual components."
It seems I was wrong thinking `autoconf`/`make` only installed shared libraries if configured with `--enable-shared`, even if `--disable-static` is present. I'll re-address with a followup patch.

This reverts commit r243297 for causing PR#24154.

llvm-svn: 244108
2015-08-05 20:03:26 +00:00
Duncan P. N. Exon Smith 1e40dc42cd DI: Rewrite the DIBuilder local variable API
Replace the general `createLocalVariable()` with two more specific
functions: `createParameterVariable()` and `createAutoVariable()`, and
rewrite the documentation.

Besides cleaning up the API, this avoids exposing the fake DWARF tags
`DW_TAG_arg_variable` and `DW_TAG_auto_variable` to frontends, and is
preparation for removing them completely.

llvm-svn: 243764
2015-07-31 17:55:53 +00:00
JF Bastien ba70e9e1e6 Fix `llvm-config` to emit the linker flag for the combined shared object built by autoconfig/make instead of the individual components.
Summary:
When LLVM is configured to build shared libraries, CMake builds each component as it's own shared object, while autoconfig/make builds them statically and then links them all together to create a single shared object. This change adds compile time config flags to `llvm-config` so it can know whether LLVM's components are separated or not and act accordingly.

This fixes `llvm-config` instead of fixing the makefiles to behave like CMake because, AIUI, LLVM's autoconfig/make build system is on the way out anyway.

This change only affects `llvm-config` from builds that use autoconfig/make.

Reviewers: jfb

Subscribers: echristo, dschuff, llvm-commits

Differential Revision: http://reviews.llvm.org/D11392

llvm-svn: 243297
2015-07-27 18:26:30 +00:00
Reid Kleckner ef9828fb47 Revert "Update LLVM bindings after r239940. ..."
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
2015-07-16 01:16:39 +00:00
Andrew Wilkins 02ee3efb0c Expose setPersonalityFn to Go
Summary:
Add Value.SetPersonality to the Go bindings. The Go
bindings' Builder.CreateLandingPad has been updated,
removing the obsolete personality argument.

Background

The personality attribute was removed from LandingPadInst
in r239940, and llvm::Function::setPersonalityFn introduced.

There was no corresponding change to either the C API or
Go bindings. The Go bindings were broken until r239940, but
that change was just to ignore the personality argument.
This broke llgo.

Reviewers: majnemer, pcc

Subscribers: deadalnix, llvm-commits, axw

Differential Revision: http://reviews.llvm.org/D11116

llvm-svn: 242289
2015-07-15 13:03:08 +00:00
Rafael Espindola 76ad232179 Remove getRelocationAddress.
Originally added in r139314.

Back then it didn't actually get the address, it got whatever value the
relocation used: address or offset.

The values in different object formats are:

* MachO: Always an offset.
* COFF: Always an address, but when talking about the virtual address of
  sections it says: "for simplicity, compilers should set this to zero".
* ELF: An offset for .o files and and address for .so files. In the case of the
  .so, the relocation in not linked to any section (sh_info is 0). We can't
  really compute an offset.

Some API mappings would be:

* Use getAddress for everything. It would be quite cumbersome. To compute the
  address elf has to follow sh_info, which can be corrupted and therefore the
  method has to return an ErrorOr. The address of the section is also the same
  for every relocation in a section, so we shouldn't have to check the error
  and fetch the value for every relocation.

* Use a getValue and make it up to the user to know what it is getting.

* Use a getOffset and:
 * Assert for dynamic ELF objects. That is a very peculiar case and it is
   probably fair to ask any tool that wants to support it to use ELF.h. The
   only tool we have that reads those (llvm-readobj) already does that. The
   only other use case I can think of is a dynamic linker.
 * Check that COFF .obj files have sections with zero virtual address spaces. If
   it turns out that some assembler/compiler produces these, we can change
   COFFObjectFile::getRelocationOffset to subtract it. Given COFF format,
   this can be done without the need for ErrorOr.

The getRelocationAddress method was never implemented for COFF. It also
had exactly one use in a very peculiar case: a shortcut for adding the
section value to a pcrel reloc on MachO.

Given that, I don't expect that there is any use out there of the C API. If
that is not the case, let me know and I will add it back with the implementation
inlined and do a proper deprecation.

llvm-svn: 241450
2015-07-06 14:55:37 +00:00
Peter Zotov 8c7e29d583 [OCaml] Bump ctypes dependency to 0.4.
ctypes 0.3 and earlier contains an interface-definig bug:
its ptr_of_raw_address accepts Int64 and not Nativeint. ctypes 0.4
was not released during the 3.6 cycle, and because of that, LLVM 3.6
was released with ctypes 0.3 as a dependency, which now breaks
the build on modern ctypes.

Unbreak.

llvm-svn: 240882
2015-06-27 14:32:30 +00:00
Daniel Jasper 22ef2c3e30 Update LLVM bindings after r239940. Apparently these aren't included in
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
2015-06-18 11:51:16 +00:00
Peter Collingbourne 58af6d1594 Add safestack attribute to LLVMAttribute enum and Go bindings. Correct
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
2015-06-15 22:16:51 +00:00
Duncan P. N. Exon Smith a9308c49ef IR: Give 'DI' prefix to debug info metadata
Finish off PR23080 by renaming the debug info IR constructs from `MD*`
to `DI*`.  The last of the `DIDescriptor` classes were deleted in
r235356, and the last of the related typedefs removed in r235413, so
this has all baked for about a week.

Note: If you have out-of-tree code (like a frontend), I recommend that
you get everything compiling and tests passing with the *previous*
commit before updating to this one.  It'll be easier to keep track of
what code is using the `DIDescriptor` hierarchy and what you've already
updated, and I think you're extremely unlikely to insert bugs.  YMMV of
course.

Back to *this* commit: I did this using the rename-md-di-nodes.sh
upgrade script I've attached to PR23080 (both code and testcases) and
filtered through clang-format-diff.py.  I edited the tests for
test/Assembler/invalid-generic-debug-node-*.ll by hand since the columns
were off-by-three.  It should work on your out-of-tree testcases (and
code, if you've followed the advice in the previous paragraph).

Some of the tests are in badly named files now (e.g.,
test/Assembler/invalid-mdcompositetype-missing-tag.ll should be
'dicompositetype'); I'll come back and move the files in a follow-up
commit.

llvm-svn: 236120
2015-04-29 16:38:44 +00:00
Duncan P. N. Exon Smith aa861aa483 DebugInfo: Remove DIArray and DITypeArray typedefs
Remove the `DIArray` and `DITypeArray` typedefs, preferring the
underlying types (`DebugNodeArray` and `MDTypeRefArray`, respectively).

llvm-svn: 235413
2015-04-21 20:07:38 +00:00
Duncan P. N. Exon Smith 60635e39b6 DebugInfo: Drop rest of DIDescriptor subclasses
Delete the remaining subclasses of (the already deleted) `DIDescriptor`.
Part of PR23080.

llvm-svn: 235404
2015-04-21 18:44:06 +00:00
Duncan P. N. Exon Smith 2fbe13540a DebugInfo: Delete subclasses of DIScope
Delete subclasses of (the already defunct) `DIScope`, updating users to
use the raw pointers from the `Metadata` hierarchy directly.

llvm-svn: 235356
2015-04-20 22:10:08 +00:00
Duncan P. N. Exon Smith c62468859a DebugInfo: Delete old subclasses of DIType
Delete subclasses of (the already deleted) `DIType` in favour of
directly using pointers from the `Metadata` hierarchy.

While `DICompositeType` wraps `MDCompositeTypeBase` and `DIDerivedType`
wraps `MDDerivedTypeBase`, most uses of each really meant the more
specific `MDCompositeType` and `MDDerivedType`.

llvm-svn: 235351
2015-04-20 21:17:32 +00:00
Duncan P. N. Exon Smith 02083539a3 DebugInfo: Remove DIDescriptor from the DIBuilder API
As a step toward killing `DIDescriptor` and its subclasses, remove it
from the `DIBuilder` API.  Replace the subclasses with appropriate
pointers from the new debug info hierarchy.  There are a couple of
possible surprises in type choices for out-of-tree frontends:

  - Subroutine types: `MDSubroutineType`, not `MDCompositeTypeBase`.
  - Composite types: `MDCompositeType`, not `MDCompositeTypeBase`.
  - Scopes: `MDScope`, not `MDNode`.
  - Generic debug info nodes: `DebugNode`, not `MDNode`.

This is part of PR23080.

llvm-svn: 235111
2015-04-16 16:36:23 +00:00
Duncan P. N. Exon Smith cd1aecfe36 DebugInfo: Require a DebugLoc in DIBuilder::insertDeclare()
Change `DIBuilder::insertDeclare()` and `insertDbgValueIntrinsic()` to
take an `MDLocation*`/`DebugLoc` parameter which it attaches to the
created intrinsic.  Assert at creation time that the `scope:` field's
subprogram matches the variable's.  There's a matching `clang` commit to
use the API.

The context for this is PR22778, which is removing the `inlinedAt:`
field from `MDLocalVariable`, instead deferring to the `!dbg` location
attached to the debug info intrinsic.  The best way to ensure we always
have a `!dbg` attachment is to require one at creation time.  I'll be
adding verifier checks next, but this API change is the best way to
shake out frontend bugs.

Note: I added an `llvm_unreachable()` in `bindings/go` and passed in
`nullptr` for the `DebugLoc`.  The `llgo` folks will eventually need to
pass a valid `DebugLoc` here.

llvm-svn: 235041
2015-04-15 21:18:07 +00:00
Peter Collingbourne 0b9c7bb9fc Go bindings: make various DIBuilder arguments optional.
r234262 changed some code in DIBuilderBindings.cpp to use the unwrap function
to unwrap debug metadata. The problem with this is that unwrap asserts that
its argument is non-null, which is not what we want in a number of places
in DIBuilder where the argument is optional. This change makes certain
arguments optional by adding null checks in places where it is required,
fixing the llgo build.

llvm-svn: 234428
2015-04-08 20:18:57 +00:00
Duncan P. N. Exon Smith 1134473f51 IR: Remove MDTupleTypedArrayWrapper::operator MDTuple*()
Remove `MDTupleTypedArrayWrapper::operator MDTuple*()`, since it causes
ambiguity (at least in some [1] compilers [2]) when using indexes to
`MDTupleTypedArrayWrapper::operator[](unsigned)` that are convertible to
(but not the same as) `unsigned`.

[1]: http://lab.llvm.org:8011/builders/sanitizer-windows/builds/2308
[2]: http://lab.llvm.org:8011/builders/clang-cmake-mips/builds/4442

llvm-svn: 234326
2015-04-07 16:50:39 +00:00
Duncan P. N. Exon Smith 3a85a72605 bindings/go: Stop using DIDescriptor::is*() and auto-casting
Go bindings edition of r234255.

llvm-svn: 234262
2015-04-07 00:08:31 +00:00
Peter Collingbourne febd93c7c9 Go bindings: use MDNode::replaceAllUsesWith instead of MDTuple::replaceAllUsesWith.
Fixes llgo following Duncan's changes to debug info in r231082. llgo needs
to replace composite types, which are no longer represented using MDTuple.

llvm-svn: 231416
2015-03-05 22:55:38 +00:00
Juergen Ributzka a57d588cb7 Restore LLVMLinkModules C API until it is properly deprecated.
Add the enum "LLVMLinkerMode" back for backwards-compatibility and add the
linker mode parameter back to the "LLVMLinkModules" function. The paramter is
ignored and has no effect.

Patch provided by: Filip Pizlo
Reviewed by: Rafael and Sean

llvm-svn: 230988
2015-03-02 18:59:38 +00:00
Andrew Wilkins 6992d5dcc5 bindings/go: expose DIBuilder::createReplaceableCompositeType
Summary:
We extend the DIBuilder type, adding a method for creating
replaceable composite types. This is necessary for creating
debug info describing self-referential types.

Reviewers: pcc

Reviewed By: pcc

Subscribers: axw, llvm-commits

Differential Revision: http://reviews.llvm.org/D7851

llvm-svn: 230951
2015-03-02 12:27:04 +00:00
Chandler Carruth 30d69c2e36 [PM] Remove the old 'PassManager.h' header file at the top level of
LLVM's include tree and the use of using declarations to hide the
'legacy' namespace for the old pass manager.

This undoes the primary modules-hostile change I made to keep
out-of-tree targets building. I sent an email inquiring about whether
this would be reasonable to do at this phase and people seemed fine with
it, so making it a reality. This should allow us to start bootstrapping
with modules to a certain extent along with making it easier to mix and
match headers in general.

The updates to any code for users of LLVM are very mechanical. Switch
from including "llvm/PassManager.h" to "llvm/IR/LegacyPassManager.h".
Qualify the types which now produce compile errors with "legacy::". The
most common ones are "PassManager", "PassManagerBase", and
"FunctionPassManager".

llvm-svn: 229094
2015-02-13 10:01:29 +00:00
Chandler Carruth 1f832f7c27 Re-sort the #include lines in bindings and examples which I managed to
miss previously.

llvm-svn: 229089
2015-02-13 09:14:30 +00:00
Peter Zotov 7b9b9d8c85 [OCaml] Add Llvm.build_empty_phi.
llvm-svn: 228395
2015-02-06 13:42:03 +00:00
Alexey Samsonov b9b8027cee SpecialCaseList: Add support for parsing multiple input files.
Summary:
This change allows users to create SpecialCaseList objects from
multiple local files. This is needed to implement a proper support
for -fsanitize-blacklist flag (allow users to specify multiple blacklists,
in addition to default blacklist, see PR22431).

DFSan can also benefit from this change, as DFSan instrumentation pass now
accepts ABI-lists both from -fsanitize-blacklist= and -mllvm -dfsan-abilist flags.

Go bindings are fixed accordingly.

Test Plan: regression test suite

Reviewers: pcc

Subscribers: llvm-commits, axw, kcc

Differential Revision: http://reviews.llvm.org/D7367

llvm-svn: 228155
2015-02-04 17:39:48 +00:00
Duncan P. N. Exon Smith 7d82313bcd IR: Return unique_ptr from MDNode::getTemporary()
Change `MDTuple::getTemporary()` and `MDLocation::getTemporary()` to
return (effectively) `std::unique_ptr<T, MDNode::deleteTemporary>`, and
clean up call sites.  (For now, `DIBuilder` call sites just call
`release()` immediately.)

There's an accompanying change in each of clang and polly to use the new
API.

llvm-svn: 226504
2015-01-19 21:30:18 +00:00
Duncan P. N. Exon Smith 946fdcc50c IR: Remove MDNodeFwdDecl
Remove `MDNodeFwdDecl` (as promised in r226481).  Aside from API
changes, there's no real functionality change here.
`MDNode::getTemporary()` now forwards to `MDTuple::getTemporary()`,
which returns a tuple with `isTemporary()` equal to true.

The main point is that we can now add temporaries of other `MDNode`
subclasses, needed for PR22235 (I introduced `MDNodeFwdDecl` in the
first place because I didn't recognize this need, and thought they were
only needed to handle forward references).

A few things left out of (or highlighted by) this commit:

  - I've had to remove the (few) uses of `std::unique_ptr<>` to deal
    with temporaries, since the destructor is no longer public.
    `getTemporary()` should probably return the equivalent of
    `std::unique_ptr<T, MDNode::deleteTemporary>`.
  - `MDLocation::getTemporary()` doesn't exist yet (worse, it actually
    does exist, but does the wrong thing: `MDNode::getTemporary()` is
    inherited and returns an `MDTuple`).
  - `MDNode` now only has one subclass, `UniquableMDNode`, and the
    distinction between them is actually somewhat confusing.

I'll fix those up next.

llvm-svn: 226501
2015-01-19 20:36:39 +00:00
Peter Zotov 343991dd8b [OCaml] Allow out-of-tree builds of LLVM bindings.
In order to use this feature, configure LLVM as usual,
but then build and install it as:

   make all install SYSTEM_LLVM_CONFIG=llvm-config

where llvm-config is the llvm-config binary installed on your
system (possibly llvm-config-VERSION on e.g. Debian).

llvm-svn: 225787
2015-01-13 12:17:56 +00:00
Peter Zotov 1f00ac9368 [OCaml] Use $CAMLORIGIN, an rpath-$ORIGIN-like mechanism in OCaml.
As a result, installations of LLVM in non-standard locations
will not require passing custom -ccopt -L flags when building
the binary, nor absolute paths would be embedded in the cma/cmxa
files. Additionally, the executables will not require changes
to LD_LIBRARY_PATH, although CAML_LD_LIBRARY_PATH still
has to be set for ocamlc without -custom.

See http://caml.inria.fr/mantis/view.php?id=6642.
Note that the patch is approved, but not merged yet.
It will be released in 4.03 and likely 4.02.

llvm-svn: 225778
2015-01-13 09:47:59 +00:00
Peter Zotov 0bd44501c3 [OCaml] [cmake] Use LLVM_LIBRARY_DIR instead of LLVM_LIBRARY_OUTPUT_INTDIR.
The latter variable is internal.

Original patch by Ramkumar Ramachandra <artagnon@gmail.com>

llvm-svn: 224977
2014-12-30 03:24:07 +00:00
Peter Zotov af6535bf12 [OCaml] Expose Llvm_executionengine.get_{global_value,function}_address.
Patch by Ramkumar Ramachandra <artagnon@gmail.com>.

Also remove Llvm_executionengine.get_pointer_to_global, as it
is actually deprecated and didn't appear in a stable release.

llvm-svn: 224801
2014-12-24 01:52:51 +00:00
Rafael Espindola c6c58d5e71 Finish removing DestroySource.
Fixes pr21901.

llvm-svn: 224782
2014-12-23 19:16:45 +00:00
Peter Zotov 4ab66cdfcb [OCaml] PR22014: OCaml bindings didn't link to libLLVM-*.so with -Wl,--as-needed
Patch by Evangelos Foutras <evangelos@foutrelis.com>.

llvm-svn: 224766
2014-12-23 13:09:59 +00:00
Peter Collingbourne cc8c906048 Go bindings: introduce Value.ConstantAsMetadata.
llvm-svn: 224179
2014-12-13 02:25:57 +00:00
Peter Collingbourne 11c5bf2a65 Go bindings: introduce llvm.TemporaryMDNode.
llvm-svn: 224178
2014-12-13 02:25:54 +00:00
Peter Collingbourne a2fc9d06d9 Go bindings: introduce Metadata.ReplaceAllUsesWith.
llvm-svn: 224177
2014-12-13 02:25:51 +00:00
Peter Collingbourne 7cdb6dc86f Go bindings: expose the Metadata type.
Also modifies SetCurrentDebugLocation to take individual arguments rather
than an MDNode.

llvm-svn: 224176
2014-12-13 02:25:49 +00:00
Peter Collingbourne 9796c09009 Go bindings: remove contextless metadata bindings.
llvm-svn: 224175
2014-12-13 02:25:45 +00:00
Duncan P. N. Exon Smith 5bf8fef580 IR: Split Metadata from Value
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
2014-12-09 18:38:53 +00:00