It was only used from LTO for a debug feature, and LTO can just create
another linker.
It is pretty odd to have a method to reset the module in the middle of a
link. It would make IdentifiedStructTypes inconsistent with the Module
for example.
llvm-svn: 254434
It has to be a bit special because:
* materializeInitFor is not really supposed to call replaceAllUsesWith.
The caller has a plain variable with Dst and expects just the
initializer to be set, not for it to be removed.
* Calling mutateType as we used to do before gets some type
inconsistency which breaks the bitcode writer.
* If linkAppendingVarProto create a dest decl with the correct type to
avoid the above problems, it needs to put the original dst init in
some side table for materializeInitFor to use.
In the end the simplest solution seems to be to just have
linkAppendingVarProto do all the work and set ValueMap[SrcGV to avoid
recursion.
llvm-svn: 254424
The difference is that now we don't error on out-of-comdat access to
internal global values. We copy them instead. This seems to match the
expectation of COFF linkers (see pr25686).
Original message:
Start deciding earlier what to link.
A traditional linker is roughly split in symbol resolution and
"copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
llvm-svn: 254418
A traditional linker is roughly split in symbol resolution and "copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
llvm-svn: 254336
Now the ValueMapper has two callbacks. The first one maps the
declaration. The ValueMapper records the mapping and then materializes
the body/initializer.
llvm-svn: 254209
They are as much trouble as aliases to declarations. They are requiring
the code generator to define a symbol with the same value as another
symbol, but the second symbol is undefined.
If representing this is important for some optimization, we could add
support for available_externally aliases. They would be *required* to
point to a declaration (or available_externally definition).
llvm-svn: 254170
The new function import pass exposed an issue when we import references
to local values on multiple importing passes. They are renamed on each
import pass, and we need to ensure that the already promoted and renamed
references existing in the dest module are correctly identified and
updated so that they aren't spuriously renamed again (due to a perceived
conflict with the newly linked reference).
llvm-svn: 254009
Summary:
The patch to move metadata linking after global value linking didn't
correctly map unmaterialized global values to null as desired. They
were in fact mapped to the source copy. It largely worked by accident
since most module linker clients destroyed the source module which
caused the source GVs to be replaced by null, but caused a failure with
LTO linking on Windows:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312869.html
The problem is that a null return value from materializeValueFor is
handled by mapping the value to self. This is the desired behavior when
materializeValueFor is passed a non-GlobalValue. The problem is how to
distinguish that case from the case where we really do want to map to
null.
This patch addresses this by passing in a new flag to the value mapper
indicating that unmapped global values should be mapped to null. Other
Value types are handled as before.
Note that the documented behavior of asserting on unmapped values when
the flag RF_IgnoreMissingValues isn't set is currently disabled with
FIXME notes due to bootstrap failures. I modified these disabled asserts
so when they are eventually enabled again it won't assert for the
unmapped values when the new RF_NullMapMissingGlobalValues flag is set.
I also considered using a callback into the value materializer, but a
flag seemed cleaner given that there are already existing flags.
I also considered modifying materializeValueFor to return the input
value when we want to map to source and then treat a null return
to mean map to null. However, there are other value materializer
subclasses that implement materializeValueFor, and they would all need
to be audited and the return values possibly changed, which seemed
error-prone.
Reviewers: dexonsmith, joker.eph
Subscribers: pcc, llvm-commits
Differential Revision: http://reviews.llvm.org/D14682
llvm-svn: 253170
Summary:
The module linker lazy links some "discardable if unused" global
values (e.g. linkonce), materializing and linking them only
if they are referenced in the module. If a comdat group contains a
linkonce member that is not referenced, however, it would not be
materialized and linked, leading to an incomplete comdat group.
If there are other object files not part of the same LTO link that also
define and use that comdat group, the linker may select the incomplete
group leading to link time unsats.
To solve this, whenever a global value body is linked, make sure we
materialize any other members of the same comdat group that are not yet
materialized. This ensures they are in the lazy link list and get linked
as well.
Added new test and adjusted old test to remove parts that didn't
make sense with fix.
Reviewers: rafael
Subscribers: dexonsmith, davidxl, llvm-commits
Differential Revision: http://reviews.llvm.org/D14516
llvm-svn: 252647
Ensure WeakAny variables are imported as ExternalWeak declarations. To
handle WeakAny more consistently and fix this issue:
1) Update helper doImportAsDefinition to properly flag WeakAny variables
and aliases as not importing defintions.
Update callers of doImportAsDefinition to remove now redundant checks for
WeakAny aliases, or ignore aliases, as appropriate.
2) Add any !doImportAsDefinition GVs to DoNotLinkFromSource set during
linking of the GV prototype, where we usually add GVs to the
DoNotLinkFromSource set for other reasons.
Remove now unnecessary adding of WeakAny aliases to
DoNotLinkFromSource set from copyGlobalAliasProto.
Remove now unnecessary guard against linking non-imported function
bodies from ModuleLinker::run.
llvm-svn: 252626
Summary:
This reverts commit r251965.
Restore "Move metadata linking after lazy global materialization/linking."
This restores commit r251926, with fixes for the LTO bootstrapping bot
failure.
The bot failure was caused by references from debug metadata to
otherwise unreferenced globals. Previously, this caused the lazy linking
to link in their defs, which is unnecessary. With this patch, because
lazy linking is complete when we encounter the metadata reference, the
materializer created a declaration. For definitions such as aliases and
comdats, it is illegal to have a declaration. Furthermore, metadata
linking should not change code generation. Therefore, when linking of
global value bodies is complete, the materializer will simply return
nullptr as the new reference for the linked metadata.
This change required fixing a different test to ensure there was a
real reference to a linkonce global that was only being reference from
metadata.
Note that the new changes to the only-needed-named-metadata.ll test
illustrate an issue with llvm-link -only-needed handling of comdat
groups, whereby it may result in an incomplete comdat group. I note this
in the test comments, but the issue is orthogonal to this patch (it can
be reproduced without any metadata at head).
Reviewers: dexonsmith, rafael, tra
Subscribers: tobiasvk, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D14447
llvm-svn: 252320
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
When converting an alias to a non-alias when the aliasee is not
imported, ensure that the linkage type is set to external so that it is
a valid linkage type. Added a test case that exposed this issue.
llvm-svn: 252054
This reverts commit r251926. I believe this is causing an LTO
bootstrapping bot failure
(http://lab.llvm.org:8080/green/job/llvm-stage2-cmake-RgLTO_build/3669/).
Haven't been able to repro it yet, but after looking at the metadata I
am pretty sure I know what is going on.
llvm-svn: 251965
Summary:
Currently, named metadata is linked before the LazilyLinkGlobalValues
list is walked and materialized/linked. As a result, references
from DISubprogram and DIGlobalVariable metadata to yet unmaterialized
functions and variables cause them to be added to the lazy linking
list and their definitions are materialized and linked.
This makes the llvm-link -only-needed option not have the intended
effect when debug information is present, as the otherwise unneeded
functions/variables are still linked in.
Additionally, for ThinLTO I have implemented a mechanism to only link
in debug metadata needed by imported functions. Moving named metadata
linking after lazy GV linking will facilitate applying this mechanism
to the LTO and "llvm-link -only-needed" cases as well.
Reviewers: dexonsmith, tra, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14195
llvm-svn: 251926
This reverts commit r251837, due to a number of bot failures of the form:
/home/grosser/buildslave/perf-x86_64-penryn-O3-polly-fast/llvm.obj/tools/llvm-link/Release+Asserts/llvm-link.o:llvm-link.cpp:function
loadIndex(llvm::LLVMContext&, llvm::Module const*): error: undefined
reference to
'llvm::object::FunctionIndexObjectFile::create(llvm::MemoryBufferRef,
llvm::LLVMContext&, llvm::Module const*, bool)'
/home/grosser/buildslave/perf-x86_64-penryn-O3-polly-fast/llvm.obj/tools/llvm-link/Release+Asserts/llvm-link.o:llvm-link.cpp:function
loadIndex(llvm::LLVMContext&, llvm::Module const*): error: undefined
reference to 'llvm::object::FunctionIndexObjectFile::takeIndex()'
I'm not sure why these are happening - I added Object to the requred
libraries in tools/llvm-link/LLVMBuild.txt and the LLVM_LINK_COMPONENTS
in tools/llvm-link/CMakeLists.txt. Confirmed for my build that these
symbols come out of libLLVMObject.a. What am I missing?
llvm-svn: 251841
Summary:
Support for necessary linkage changes and symbol renaming during
ThinLTO function importing.
Also includes llvm-link support for manually importing functions
and associated llvm-link based tests.
Note that this does not include support for intelligently importing
metadata, which is currently imported duplicate times. That support will
be in the follow-on patch, and currently is ignored by the tests.
Reviewers: dexonsmith, joker.eph, davidxl
Subscribers: tobiasvk, tejohnson, llvm-commits
Differential Revision: http://reviews.llvm.org/D13515
llvm-svn: 251837
As usual, this is a polymorphic hierarchy without polymorphic ownership,
so simply make the dtor protected non-virtual, protected default copy
ctor/assign, and make derived classes final. The derived classes will
pick up correct default public copy ops (and dtor) implicitly.
(wish I could add -Wdeprecated to the build, but last time I tried it
triggered on some system headers I still need to look into/figure out)
llvm-svn: 250747
This was a flawed change - it just caused the getElementType call to be
deferred until later, when we really need to remove it. Now that the IR
for GlobalAliases has been updated, the root cause is addressed that way
instead and this change is no longer needed (and in fact gets in the way
- because we want to pass the pointee type directly down further).
Follow up patches to push this through GlobalValue, bitcode format, etc,
will come along soon.
This reverts commit 236160.
llvm-svn: 247585
-only-needed -- link in only symbols needed by destination module
-internalize -- internalize linked symbols
Differential Revision: http://reviews.llvm.org/D12459
llvm-svn: 246561
Instead of cloning distinct `MDNode`s when linking in a module, just
move them over. The module linker destroys the source module, so the
old node would otherwise just be leaked on the context. Create the new
node in place. This also reduces the number of cloned uniqued nodes
(since it's less likely their operands have changed).
This mapping strategy is only correct when we're discarding the source,
so the linker turns it on via a ValueMapper flag, `RF_MoveDistinctMDs`.
There's nothing observable in terms of `llvm-link` output here: the
linked module should be semantically identical.
I'll be adding more 'distinct' nodes to the debug info metadata graph in
order to break uniquing cycles, so the benefits of this will partly come
in future commits. However, we should get some gains immediately, since
we have a fair number of 'distinct' `DILocation`s being linked in.
llvm-svn: 243883
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
The personality routine currently lives in the LandingPadInst.
This isn't desirable because:
- All LandingPadInsts in the same function must have the same
personality routine. This means that each LandingPadInst beyond the
first has an operand which produces no additional information.
- There is ongoing work to introduce EH IR constructs other than
LandingPadInst. Moving the personality routine off of any one
particular Instruction and onto the parent function seems a lot better
than have N different places a personality function can sneak onto an
exceptional function.
Differential Revision: http://reviews.llvm.org/D10429
llvm-svn: 239940
`LLVM_ENABLE_MODULES` builds sometimes fail because `Intrinsics.td`
needs to regenerate `Instrinsics.h` before anyone can include anything
from the LLVM_IR module. Represent the dependency explicitly to prevent
that.
llvm-svn: 239796
On error, the temporary output stream wouldn't be flushed and therefore the
caller would see an empty error message.
Patch by Antoine Pitrou
Differential Revision: http://reviews.llvm.org/D10241
llvm-svn: 239646
Many of the callers already have the pointer type anyway, and for the
couple of callers that don't it's pretty easy to call PointerType::get
on the pointee type and address space.
This avoids LLParser from using PointerType::getElementType when parsing
GlobalAliases from IR.
llvm-svn: 236160
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
Add a flag to lib/Linker (and `llvm-link`) to override linkage rules.
When set, the functions in the source module *always* replace those in
the destination module.
The `llvm-link` option is `-override=abc.ll`. All the "regular" modules
are loaded and linked first, followed by the `-override` modules. This
is useful for debugging workflows where some subset of the module (e.g.,
a single function) is extracted into a separate file where it's
optimized differently, before being merged back in.
Patch by Luqman Aden!
llvm-svn: 235473
Gut the `DIDescriptor` wrappers around `MDLocalScope` subclasses. Note
that `DILexicalBlock` wraps `MDLexicalBlockBase`, not `MDLexicalBlock`.
llvm-svn: 234850
`DIDescriptor`'s subclasses allow construction from incompatible
pointers, and `DIDescriptor` defines a series of `isa<>`-like functions
(e.g., `isCompileUnit()` instead of `isa<MDCompileUnit>()`) that clients
tend to use like this:
if (DICompileUnit(N).isCompileUnit())
foo(DICompileUnit(N));
These construction patterns work together to make `DIDescriptor` behave
differently from normal pointers.
Instead, use built-in `isa<>`, `dyn_cast<>`, etc., and only build
`DIDescriptor`s from pointers that are valid for their type.
I've split this into a few commits for different parts of LLVM and clang
(to decrease the patch size and increase the chance of review).
Generally the changes I made were NFC, but in a few places I made things
stricter if it made sense from the surrounded code.
Eventually a follow-up commit will remove the API for the "old" way.
llvm-svn: 234255
This reverts commit r233254, effectively reapplying r233164 (and its
successors), with an additional testcase for when subprograms match
exactly. This fixes PR22792 (again).
I'm using the same approach, but I've moved up the call to
`stripReplacedSubprograms()`. The function pointers need to be dropped
before mapping any metadata from the source module, or else this can
drop the function from new subprograms that have merged (via Metadata
uniquing) with the old ones. Dropping the pointers first prevents them
from merging.
**** The original commit message follows. ****
Linker: Drop function pointers for overridden subprograms
Instead of dropping subprograms that have been overridden, just set
their function pointers to `nullptr`. This is a minor adjustment to the
stop-gap fix for PR21910 committed in r224487, and fixes the crasher
from PR22792.
The problem that r224487 put a band-aid on: how do we find the canonical
subprogram for a `Function`? Since the backend currently relies on
`DebugInfoFinder` (which does a naive in-order traversal of compile
units and picks the first subprogram) for this, r224487 tried dropping
non-canonical subprograms.
Dropping subprograms fails because the backend *also* builds up a map
from subprogram to compile unit (`DwarfDebug::SPMap`) based on the
subprogram lists. A missing subprogram causes segfaults later when an
inlined reference (such as in this testcase) is created.
Instead, just drop the `Function` pointer to `nullptr`, which nicely
mirrors what happens when an already-inlined `Function` is optimized
out. We can't really be sure that it's the same definition anyway, as
the testcase demonstrates.
This still isn't completely satisfactory. Two flaws at least that I can
think of:
- I still haven't found a straightforward way to make this symmetric
in the IR. (Interestingly, the DWARF output is already symmetric,
and I've tested for that to be sure we don't regress.)
- Using `DebugInfoFinder` to find the canonical subprogram for a
function is kind of crazy. We should just attach metadata to the
function, like this:
define weak i32 @foo(i32, i32) !dbg !MDSubprogram(...) {
llvm-svn: 233302
Instead of dropping subprograms that have been overridden, just set
their function pointers to `nullptr`. This is a minor adjustment to the
stop-gap fix for PR21910 committed in r224487, and fixes the crasher
from PR22792.
The problem that r224487 put a band-aid on: how do we find the canonical
subprogram for a `Function`? Since the backend currently relies on
`DebugInfoFinder` (which does a naive in-order traversal of compile
units and picks the first subprogram) for this, r224487 tried dropping
non-canonical subprograms.
Dropping subprograms fails because the backend *also* builds up a map
from subprogram to compile unit (`DwarfDebug::SPMap`) based on the
subprogram lists. A missing subprogram causes segfaults later when an
inlined reference (such as in this testcase) is created.
Instead, just drop the `Function` pointer to `nullptr`, which nicely
mirrors what happens when an already-inlined `Function` is optimized
out. We can't really be sure that it's the same definition anyway, as
the testcase demonstrates.
This still isn't completely satisfactory. Two flaws at least that I can
think of:
- I still haven't found a straightforward way to make this symmetric
in the IR. (Interestingly, the DWARF output is already symmetric,
and I've tested for that to be sure we don't regress.)
- Using `DebugInfoFinder` to find the canonical subprogram for a
function is kind of crazy. We should just attach metadata to the
function, like this:
define weak i32 @foo(i32, i32) !dbg !MDSubprogram(...) {
llvm-svn: 233164
Summary:
Now that the DataLayout is a mandatory part of the module, let's start
cleaning the codebase. This patch is a first attempt at doing that.
This patch is not exactly NFC as for instance some places were passing
a nullptr instead of the DataLayout, possibly just because there was a
default value on the DataLayout argument to many functions in the API.
Even though it is not purely NFC, there is no change in the
validation.
I turned as many pointer to DataLayout to references, this helped
figuring out all the places where a nullptr could come up.
I had initially a local version of this patch broken into over 30
independant, commits but some later commit were cleaning the API and
touching part of the code modified in the previous commits, so it
seemed cleaner without the intermediate state.
Test Plan:
Reviewers: echristo
Subscribers: llvm-commits
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231740
We would set the body of a struct type (therefore making it non-opaque)
but were forgetting to move it to the non-opaque set.
Fixes pr22807.
llvm-svn: 231442
Summary:
DataLayout keeps the string used for its creation.
As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().
Get rid of DataLayoutPass: the DataLayout is in the Module
The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.
Make DataLayout Non-Optional in the Module
Module->getDataLayout() will never returns nullptr anymore.
Reviewers: echristo
Subscribers: resistor, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D7992
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231270
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
When debugging LTO issues with ld64, we use -save-temps to save the merged
optimized bitcode file, then invoke ld64 again on the single bitcode file to
speed up debugging code generation passes and ld64 stuff after code generation.
llvm linking a single bitcode file via lto_codegen_add_module will generate a
different bitcode file from the single input. With the newly-added
lto_codegen_set_module, we can make sure the destination module is the same as
the input.
lto_codegen_set_module will transfer the ownship of the module to code
generator.
rdar://19024554
llvm-svn: 230290
This commit makes the following changes:
- Stop issuing a warning when the triples' string representations do not match
exactly if the Triple objects generated from the strings compare equal.
- On Apple platforms, choose the triple that has the larger minimum version
number.
rdar://problem/16743513
Differential Revision: http://reviews.llvm.org/D7591
llvm-svn: 228999
This allows IDEs to recognize the entire set of header files for
each of the core LLVM projects.
Differential Revision: http://reviews.llvm.org/D7526
Reviewed By: Chris Bieneman
llvm-svn: 228798
ConstantArrays constructed during linking can cause quadratic memory
explosion. An example is the ConstantArrays constructed when linking in
GlobalVariables with appending linkage.
Releasing all unused constants can cause a 20% LTO compile-time
slowdown for a large application. So this commit releases unused ConstantArrays
only.
rdar://19040716. It reduces memory footprint from 20+G to 6+G.
llvm-svn: 226592
The bitcode reading interface used std::error_code to report an error to the
callers and it is the callers job to print diagnostics.
This is not ideal for error handling or diagnostic reporting:
* For error handling, all that the callers care about is 3 possibilities:
* It worked
* The bitcode file is corrupted/invalid.
* The file is not bitcode at all.
* For diagnostic, it is user friendly to include far more information
about the invalid case so the user can find out what is wrong with the
bitcode file. This comes up, for example, when a developer introduces a
bug while extending the format.
The compromise we had was to have a lot of error codes.
With this patch we use the DiagnosticHandler to communicate with the
human and std::error_code to communicate with the caller.
This allows us to have far fewer error codes and adds the infrastructure to
print better diagnostics. This is so because the diagnostics are printed when
he issue is found. The code that detected the problem in alive in the stack and
can pass down as much context as needed. As an example the patch updates
test/Bitcode/invalid.ll.
Using a DiagnosticHandler also moves the fatal/non-fatal error decision to the
caller. A simple one like llvm-dis can just use fatal errors. The gold plugin
needs a bit more complex treatment because of being passed non-bitcode files. An
hypothetical interactive tool would make all bitcode errors non-fatal.
llvm-svn: 225562
`MDNode::replaceOperandWith()` changes all instances of metadata. Stop
using it when linking module flags, since (due to uniquing) the flag
values could be used by other metadata.
Instead, use new API `NamedMDNode::setOperand()` to update the reference
directly.
llvm-svn: 225397
Instead of reusing the name `MapValue()` when mapping `Metadata`, use
`MapMetadata()`. The old name doesn't make much sense after the
`Metadata`/`Value` split.
llvm-svn: 224566
This reverts commit r224416, reapplying r224389. The buildbots hadn't
recovered after my revert, waiting until David reverted a couple of his
commits. It looks like it was just bad timing (where we were both
modifying code related to the same assertion). Trying again...
Here's the original text:
When a function gets replaced by `ModuleLinker`, drop superseded
subprograms. This ensures that the "first" subprogram pointing at a
function is the same one that `!dbg` references point at.
This is a stop-gap fix for PR21910. Notably, this fixes Release+Asserts
bootstraps that are currently asserting out in
`LexicalScopes::initialize()` due to the explicit instantiations in
`lib/IR/Dominators.cpp` eventually getting replaced by -argpromotion.
llvm-svn: 224487
When a function gets replaced by `ModuleLinker`, drop superseded
subprograms. This ensures that the "first" subprogram pointing at a
function is the same one that `!dbg` references point at.
This is a stop-gap fix for PR21910. Notably, this fixes Release+Asserts
bootstraps that are currently asserting out in
`LexicalScopes::initialize()` due to the explicit instantiations in
`lib/IR/Dominators.cpp` eventually getting replaced by -argpromotion.
llvm-svn: 224389
r223763 was made to work around a temporary issue where a user of the
JIT was passing down a declaration (incorrectly). This shouldn't
occur, so assert rather than silently continue.
llvm-svn: 224277
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
This is a revert of r223521 in spirit, if not in content. I am not
sure why declarations ended up in LazilyLinkGlobalValues in the first
place; that will take some more investigation.
llvm-svn: 223763
We were already lazily linking functions, but all GlobalValues can be treated
uniformly for this.
The test updates are to ensure that a given GlobalValue is still linked in.
This fixes pr21494.
llvm-svn: 223681
The non-opaque part can be structurally uniqued. To keep this to just
a hash lookup, we don't try to unique cyclic types.
Also change the type mapping algorithm to be optimistic about a type
not being recursive and only create a new type when proven to be wrong.
This is not as strong as trying to speculate that we can keep the source
type, but is simpler (no speculation to revert) and more powerfull
than what we had before (we don't copy non-recursive types at least).
I initially wrote this to try to replace the name based type merging.
It is not strong enough to replace it, but is is a useful addition.
With this patch the number of named struct types is a clang lto bootstrap goes
from 49674 to 15986.
llvm-svn: 223278
When lazy reading a module, the types used in a function will not be visible to
a TypeFinder until the body is read.
This patch fixes that by asking the module for its identified struct types.
If a materializer is present, the module asks it. If not, it uses a TypeFinder.
This fixes pr21374.
I will be the first to say that this is ugly, but it was the best I could find.
Some of the options I looked at:
* Asking the LLVMContext. This could be made to work for gold, but not currently
for ld64. ld64 will load multiple modules into a single context before merging
them. This causes us to see types from future merges. Unfortunately,
MappedTypes is not just a cache when it comes to opaque types. Once the
mapping has been made, we have to remember it for as long as the key may
be used. This would mean moving MappedTypes to the Linker class and having
to drop the Linker::LinkModules static methods, which are visible from C.
* Adding an option to ignore function bodies in the TypeFinder. This would
fix the PR by picking the worst result. It would work, but unfortunately
we are currently quite dependent on the upfront type merging. I will
try to reduce our dependency, but it is not clear that we will be able
to get rid of it for now.
The only clean solution I could think of is making the Module own the types.
This would have other advantages, but it is a much bigger change. I will
propose it, but it is nice to have this fixed while that is discussed.
With the gold plugin, this patch takes the number of types in the LTO clang
binary from 52817 to 49669.
llvm-svn: 223215
Patch by Ben Gamari!
This redefines the `prefix` attribute introduced previously and
introduces a `prologue` attribute. There are a two primary usecases
that these attributes aim to serve,
1. Function prologue sigils
2. Function hot-patching: Enable the user to insert `nop` operations
at the beginning of the function which can later be safely replaced
with a call to some instrumentation facility
3. Runtime metadata: Allow a compiler to insert data for use by the
runtime during execution. GHC is one example of a compiler that
needs this functionality for its tables-next-to-code functionality.
Previously `prefix` served cases (1) and (2) quite well by allowing the user
to introduce arbitrary data at the entrypoint but before the function
body. Case (3), however, was poorly handled by this approach as it
required that prefix data was valid executable code.
Here we redefine the notion of prefix data to instead be data which
occurs immediately before the function entrypoint (i.e. the symbol
address). Since prefix data now occurs before the function entrypoint,
there is no need for the data to be valid code.
The previous notion of prefix data now goes under the name "prologue
data" to emphasize its duality with the function epilogue.
The intention here is to handle cases (1) and (2) with prologue data and
case (3) with prefix data.
References
----------
This idea arose out of discussions[1] with Reid Kleckner in response to a
proposal to introduce the notion of symbol offsets to enable handling of
case (3).
[1] http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-May/073235.html
Test Plan: testsuite
Differential Revision: http://reviews.llvm.org/D6454
llvm-svn: 223189
The explicit set of destination types is not fully redundant when lazy loading
since the TypeFinder will not find types used only in function bodies.
This keeps the logic to drop the name of mapped types since it still helps
with avoiding further renaming.
llvm-svn: 223043
Instead of keeping an explicit set, just drop the names of types we choose
to map to some other type.
This has the advantage that the name of the unused will not cause the context
to rename types on module read.
llvm-svn: 222986
The original patch would fail when:
* A dst opaque type (%A) is matched with a src type (%A).
* A src opaque (%E) type is then speculatively matched with %A and the
speculation fails afterward.
* When rolling back the speculation we would cancel the source %A to dest
%A mapping.
The fix is to keep an explicit list of which resolutions are speculative.
Original message:
Fix overly aggressive type merging.
If we find out that two types are *not* isomorphic, we learn nothing about
opaque sub types in both the source and destination.
llvm-svn: 222923
This reverts commit r222727, which causes LTO bootstrap failures.
Last passing @ r222698:
http://lab.llvm.org:8080/green/job/clang-Rlto_master_build/532/
First failing @ r222843:
http://lab.llvm.org:8080/green/job/clang-Rlto_master_build/533/
Internal bootstraps pointed at a much narrower range: r222725 is
passing, and r222731 is failing.
LTO crashes while handling libclang.dylib:
http://lab.llvm.org:8080/green/job/clang-Rlto_master_build/533/consoleFull#-158682280549ba4694-19c4-4d7e-bec5-911270d8a58c
GEP is not of right type for indices!
%InfoObj.i.i = getelementptr inbounds %"class.llvm::OnDiskIterableChainedHashTable"* %.lcssa, i64 0, i32 0, i32 4, !dbg !123627
%"class.clang::serialization::reader::ASTIdentifierLookupTrait" = type { %"class.clang::ASTReader.31859"*, %"class.clang::serialization::ModuleFile.31870"*, %"class.clang::IdentifierInfo"* }LLVM ERROR: Broken function found, compilation aborted!
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Looks like the new algorithm doesn't merge types aggressively enough.
llvm-svn: 222895
This changes the order in which different types are passed to get, but
one order is not inherently better than the other.
The main motivation is that this simplifies linkDefinedTypeBodies now that
it is only linking "real" opaque types. It is also means that we only have to
call it once and that we don't need getImpl.
A small change in behavior is that we don't copy type names when resolving
opaque types. This is an improvement IMHO, but it can be added back if
desired. A test is included with the new behavior.
llvm-svn: 222764
Exactly the same checks are present in areTypesIsomorphic.
This might have been a premature performance optimization. I cannot reproduce
any slowdown with this patch.
llvm-svn: 222758
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.
This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...
llvm-svn: 222334
Having two ways to do this doesn't seem terribly helpful and
consistently using the insert version (which we already has) seems like
it'll make the code easier to understand to anyone working with standard
data structures. (I also updated many references to the Entry's
key and value to use first() and second instead of getKey{Data,Length,}
and get/setValue - for similar consistency)
Also removes the GetOrCreateValue functions so there's less surface area
to StringMap to fix/improve/change/accommodate move semantics, etc.
llvm-svn: 222319
Instead, we're going to separate metadata from the Value hierarchy. See
PR21532.
This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.
llvm-svn: 221711
Change `NamedMDNode::getOperator()` from returning `MDNode *` to
returning `Value *`. To reduce boilerplate at some call sites, add a
`getOperatorAsMDNode()` for named metadata that's expected to only
return `MDNode` -- for now, that's everything, but debug node named
metadata (such as llvm.dbg.cu and llvm.dbg.sp) will soon change. This
is part of PR21433.
Note that there's a follow-up patch to clang for the API change.
llvm-svn: 221375
The issue was that linkAppendingVarProto does the full linking job, including
deleting the old dst variable. The fix is just to call it and return early
if we have a GV with appending linkage.
original message:
Refactor duplicated code in liking GlobalValues.
There is quiet a bit of logic that is common to any GlobalValue but was
duplicated for Functions, GlobalVariables and GlobalAliases.
While at it, merge visibility even when comdats are used, fixing pr21415.
llvm-svn: 221098
This commit introduces heap-use-after-free detected by ASan. Here is the output
for one of several tests that detect it:
******************** TEST 'LLVM :: Linker/AppendingLinkage.ll' FAILED ********************
Command Output (stderr):
--
=================================================================
==2122==ERROR: AddressSanitizer: heap-use-after-free on address 0x60c00000b9c8 at pc 0x0000005d05d1 bp 0x7fff64ed27c0 sp 0x7fff64ed27b8
READ of size 4 at 0x60c00000b9c8 thread T0
#0 0x5d05d0 in llvm::GlobalValue::setUnnamedAddr(bool) /usr/local/google/home/chandlerc/src/llvm/build/../include/llvm/IR/GlobalValue.h:115:35
#1 0x69fff1 in (anonymous namespace)::ModuleLinker::linkGlobalValueProto(llvm::GlobalValue*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1041:5
#2 0x697229 in (anonymous namespace)::ModuleLinker::run() /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1485:9
#3 0x696542 in llvm::Linker::linkInModule(llvm::Module*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1621:10
#4 0x4a2db7 in main /usr/local/google/home/chandlerc/src/llvm/build/../tools/llvm-link/llvm-link.cpp:116:9
#5 0x7f4ae61e5ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287
#6 0x41eb71 in _start (/usr/local/google/home/chandlerc/src/llvm/build/bin/llvm-link+0x41eb71)
0x60c00000b9c8 is located 72 bytes inside of 128-byte region [0x60c00000b980,0x60c00000ba00)
freed by thread T0 here:
#0 0x4a1e6b in operator delete(void*) /usr/local/google/home/chandlerc/src/llvm/opt-build/../projects/compiler-rt/lib/asan/asan_new_delete.cc:94:3
#1 0x5d1a7a in llvm::iplist<llvm::GlobalVariable, llvm::ilist_traits<llvm::GlobalVariable> >::erase(llvm::ilist_iterator<llvm::GlobalVariable>) /usr/local/google/home/chandlerc/src/llvm/build/../inclu
de/llvm/ADT/ilist.h:466:5
#2 0x5d1980 in llvm::GlobalVariable::eraseFromParent() /usr/local/google/home/chandlerc/src/llvm/build/../lib/IR/Globals.cpp:204:3
#3 0x6a8a4d in (anonymous namespace)::ModuleLinker::linkAppendingVarProto(llvm::GlobalVariable*, llvm::GlobalVariable const*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.
cpp:980:3
#4 0x6a7403 in (anonymous namespace)::ModuleLinker::linkGlobalVariableProto(llvm::GlobalVariable const*, llvm::GlobalValue*, bool) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkMod
ules.cpp:1074:11
#5 0x69ff4e in (anonymous namespace)::ModuleLinker::linkGlobalValueProto(llvm::GlobalValue*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1028:13
#6 0x697229 in (anonymous namespace)::ModuleLinker::run() /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1485:9
#7 0x696542 in llvm::Linker::linkInModule(llvm::Module*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1621:10
#8 0x4a2db7 in main /usr/local/google/home/chandlerc/src/llvm/build/../tools/llvm-link/llvm-link.cpp:116:9
#9 0x7f4ae61e5ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287
previously allocated by thread T0 here:
#0 0x4a192b in operator new(unsigned long) /usr/local/google/home/chandlerc/src/llvm/opt-build/../projects/compiler-rt/lib/asan/asan_new_delete.cc:62:35
#1 0x61d85c in llvm::User::operator new(unsigned long, unsigned int) /usr/local/google/home/chandlerc/src/llvm/build/../lib/IR/User.cpp:57:19
#2 0x6a7525 in (anonymous namespace)::ModuleLinker::linkGlobalVariableProto(llvm::GlobalVariable const*, llvm::GlobalValue*, bool) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkMod
ules.cpp:1100:3
#3 0x69ff4e in (anonymous namespace)::ModuleLinker::linkGlobalValueProto(llvm::GlobalValue*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1028:13
#4 0x697229 in (anonymous namespace)::ModuleLinker::run() /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1485:9
#5 0x696542 in llvm::Linker::linkInModule(llvm::Module*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1621:10
#6 0x4a2db7 in main /usr/local/google/home/chandlerc/src/llvm/build/../tools/llvm-link/llvm-link.cpp:116:9
#7 0x7f4ae61e5ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287
SUMMARY: AddressSanitizer: heap-use-after-free /usr/local/google/home/chandlerc/src/llvm/build/../include/llvm/IR/GlobalValue.h:115 llvm::GlobalValue::setUnnamedAddr(bool)
Shadow bytes around the buggy address:
0x0c187fff96e0: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
0x0c187fff96f0: 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa fa
0x0c187fff9700: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fa
0x0c187fff9710: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
0x0c187fff9720: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
=>0x0c187fff9730: fd fd fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd
0x0c187fff9740: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
0x0c187fff9750: fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa fa
0x0c187fff9760: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x0c187fff9770: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
0x0c187fff9780: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Heap right redzone: fb
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack partial redzone: f4
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
ASan internal: fe
==2122==ABORTING
llvm-svn: 221096
This removes calls to isMaterializable in the following cases:
* It was redundant with a call to isDeclaration now that isDeclaration returns
the correct answer for materializable functions.
* It was followed by a call to Materialize. Just call Materialize and check EC.
llvm-svn: 221050
There is quiet a bit of logic that is common to any GlobalValue but was
duplicated for Functions, GlobalVariables and GlobalAliases.
While at it, merge visibility even when comdats are used, fixing pr21415.
llvm-svn: 221014
The langref says:
LLVM explicitly allows declarations of global variables to be marked
constant, even if the final definition of the global is not. This
capability can be used to enable slightly better optimization of the
program, but requires the language definition to guarantee that
optimizations based on the ‘constantness’ are valid for the
translation units that do not include the definition.
Given that definition, when merging two declarations, we have to drop
constantness if of of them is not marked contant, since the Module
without the constant marker might not have the necessary guarantees.
llvm-svn: 220927
I noticed that it was untested, and forcing it on caused some tests to fail:
LLVM :: Linker/metadata-a.ll
LLVM :: Linker/prefixdata.ll
LLVM :: Linker/type-unique-odr-a.ll
LLVM :: Linker/type-unique-simple-a.ll
LLVM :: Linker/type-unique-simple2-a.ll
LLVM :: Linker/type-unique-simple2.ll
LLVM :: Linker/type-unique-type-array-a.ll
LLVM :: Linker/unnamed-addr1-a.ll
LLVM :: Linker/visibility1.ll
If it is to be resurrected, it has to be fixed and we should probably have a
-preserve-source command line option in llvm-mc and run tests with and without
it.
llvm-svn: 220741
To do this, change the representation of lazy loaded functions.
The previous representation cannot differentiate between a function whose body
has been removed and one whose body hasn't been read from the .bc file. That
means that in order to drop a function, the entire body had to be read.
llvm-svn: 220580
When linking llvm.global_ctors with the optional third element we have to handle
it specially and only copy the elements whose keys were also copied.
llvm-svn: 217281
We were setting the comdat when functions were copied in the initial pass, but
not when they were linked only when we found out that they are needed.
llvm-svn: 215765
An optional third field was added to `llvm.global_ctors` (and
`llvm.global_dtors`) in r209015. Most of the code has been changed to
deal with both versions of the variables. Users of the C API might
create either version, the helper functions in LLVM create the two-field
version, and clang now creates the three-field version.
However, the BitcodeReader was changed to always upgrade to the
three-field version. This created an unnecessary inconsistency in the
IR before/after serializing to bitcode.
This commit resolves the inconsistency by making the third field truly
optional (and not upgrading in the bitcode reader). Since `llvm-link`
was relying on this upgrade code, rather than deleting it I've moved it
into `ModuleLinker`, where it upgrades these arrays as necessary to
resolve inconsistencies between modules.
The ideal resolution would be to remove the 2-field version and make the
third field required. I filed PR20506 to track that.
I changed `test/Bitcode/upgrade-global-ctors.ll` to a negative test and
duplicated the `llvm-link` check in `test/Linker/global_ctors.ll` to
check both upgrade directions.
Since I came across this as part of PR5680 (serializing use-list order),
I've also added the missing `verify-uselistorder` RUN line to
`test/Bitcode/metadata-2.ll`.
llvm-svn: 215457
Type::dump() doesn't print a newline, which makes for a poor
experience in a debugger. This looks like it was an ommission
considering Value::dump() two lines above, so I've changed Type to add
a newline as well.
Of the two in-tree callers, one added a newline anyway, and I've
updated the other one to use Type::print instead.
llvm-svn: 215421
This new IR facility allows us to represent the object-file semantic of
a COMDAT group.
COMDATs allow us to tie together sections and make the inclusion of one
dependent on another. This is required to implement features like MS
ABI VFTables and optimizing away certain kinds of initialization in C++.
This functionality is only representable in COFF and ELF, Mach-O has no
similar mechanism.
Differential Revision: http://reviews.llvm.org/D4178
llvm-svn: 211920
Alias with unnamed_addr were in a strange state. It is stored in GlobalValue,
the language reference talks about "unnamed_addr aliases" but the verifier
was rejecting them.
It seems natural to allow unnamed_addr in aliases:
* It is a property of how it is accessed, not of the data itself.
* It is perfectly possible to write code that depends on the address
of an alias.
This patch then makes unname_addr legal for aliases. One side effect is that
the syntax changes for a corner case: In globals, unnamed_addr is now printed
before the address space.
llvm-svn: 210302
This patch changes GlobalAlias to point to an arbitrary ConstantExpr and it is
up to MC (or the system assembler) to decide if that expression is valid or not.
This reduces our ability to diagnose invalid uses and how early we can spot
them, but it also lets us do things like
@test5 = alias inttoptr(i32 sub (i32 ptrtoint (i32* @test2 to i32),
i32 ptrtoint (i32* @bar to i32)) to i32*)
An important implication of this patch is that the notion of aliased global
doesn't exist any more. The alias has to encode the information needed to
access it in its metadata (linkage, visibility, type, etc).
Another consequence to notice is that getSection has to return a "const char *".
It could return a NullTerminatedStringRef if there was such a thing, but when
that was proposed the decision was to just uses "const char*" for that.
llvm-svn: 210062
This patch changes the design of GlobalAlias so that it doesn't take a
ConstantExpr anymore. It now points directly to a GlobalObject, but its type is
independent of the aliasee type.
To avoid changing all alias related tests in this patches, I kept the common
syntax
@foo = alias i32* @bar
to mean the same as now. The cases that used to use cast now use the more
general syntax
@foo = alias i16, i32* @bar.
Note that GlobalAlias now behaves a bit more like GlobalVariable. We
know that its type is always a pointer, so we omit the '*'.
For the bitcode, a nice surprise is that we were writing both identical types
already, so the format change is minimal. Auto upgrade is handled by looking
through the casts and no new fields are needed for now. New bitcode will
simply have different types for Alias and Aliasee.
One last interesting point in the patch is that replaceAllUsesWith becomes
smart enough to avoid putting a ConstantExpr in the aliasee. This seems better
than checking and updating every caller.
A followup patch will delete getAliasedGlobal now that it is redundant. Another
patch will add support for an explicit offset.
llvm-svn: 209007
This allows code to statically accept a Function or a GlobalVariable, but
not an alias. This is already a cleanup by itself IMHO, but the main
reason for it is that it gives a lot more confidence that the refactoring to fix
the design of GlobalAlias is correct. That will be a followup patch.
llvm-svn: 208716
`ModuleLinker::getLinkageResult()` shouldn't create symbols with local
linkage and non-default visibility -- in fact, symbols with local
linkage shouldn't be merged at all. Assert to that effect.
llvm-svn: 208262
Provide triple and data layout as well as module names (or empty string) when there's a mismatch.
Differential Revision: http://llvm-reviews.chandlerc.com/D2971
llvm-svn: 203009
Now that DataLayout is not a pass, store one in Module.
Since the C API expects to be able to get a char* to the datalayout description,
we have to keep a std::string somewhere. This patch keeps it in Module and also
uses it to represent modules without a DataLayout.
Once DataLayout is mandatory, we should probably move the string to DataLayout
itself since it won't be necessary anymore to represent the special case of a
module without a DataLayout.
llvm-svn: 202190
The SuppressWarnings flag, unfortunately, isn't very useful for custom tools
that want to use the LLVM module linker. So I'm changing it to a parameter of
the Linker, and the flag itself moves to the llvm-link tool.
For the time being as SuppressWarnings is pretty much the only "option" it
seems reasonable to propagate it to Linker objects. If we end up with more
options in the future, some sort of "struct collecting options" may be a
better idea.
llvm-svn: 201819
Move copying of global initializers below the cloning of functions.
The BlockAddress doesn't have access to the correct basic blocks until the
functions have been cloned. This causes the BlockAddress to point to the old
values. Just wait until the functions have been cloned before copying the
initializers.
PR13163
llvm-svn: 199354
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.
Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:
define available_externally dllimport void @f() {}
@Var = dllexport global i32 1, align 4
Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.
llvm-svn: 199218
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.
Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:
define available_externally dllimport void @f() {}
@Var = dllexport global i32 1, align 4
Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.
llvm-svn: 199204
The BlockAddress doesn't have access to the correct basic blocks until the
functions have been cloned. This causes the BlockAddress to point to the old
values. Just wait until the functions have been cloned before copying the
initializers.
PR13163
llvm-svn: 194218
This deletes the Module ivar instead of having the LTO code generater do it. It
also sets the pointer to 'NULL', so that if it's used again it will abort
quickly.
llvm-svn: 192778
This was regression from r134829. When linking we have to be conservative. If
one of the symbols has a significant address, then the result should have it
too.
llvm-svn: 189935
Extend LinkModules to pass a ValueMaterializer to RemapInstruction and friends to lazily create Functions for lazily linked globals. This is a big win when linking small modules with large (mostly unused) library modules.
llvm-svn: 182776
Now that we hava a convinient place to keep it, remeber the set of
identified structs as we merge modules.
This speeds up the linking of all the bitcode files in clang with the
gold plugin and -plugin-opt=emit-llvm (i.e., link only, no codegen) from
5:25 minutes to 13.6 seconds!
Patch by Xiaofei Wan!
llvm-svn: 181104
Update comments, fix * placement, fix method names that are not
used in clang, add a linkInModule that takes a Mode and put it
in Linker.cpp.
llvm-svn: 181099
the things, and renames it to CBindingWrapping.h. I also moved
CBindingWrapping.h into Support/.
This new file just contains the macros for defining different wrap/unwrap
methods.
The calls to those macros, as well as any custom wrap/unwrap definitions
(like for array of Values for example), are put into corresponding C++
headers.
Doing this required some #include surgery, since some .cpp files relied
on the fact that including Wrap.h implicitly caused the inclusion of a
bunch of other things.
This also now means that the C++ headers will include their corresponding
C API headers; for example Value.h must include llvm-c/Core.h. I think
this is harmless, since the C API headers contain just external function
declarations and some C types, so I don't believe there should be any
nasty dependency issues here.
llvm-svn: 180881
This may be causing a failure on some buildbots:
Referencing function in another module!
tail call fastcc void @_ZL11EvaluateOpstPtRj(i16 zeroext %17, i16* %Vals, i32* %NumVals), !dbg !219
Referencing function in another module!
tail call fastcc void @_ZL11EvaluateOpstPtRj(i16 zeroext %19, i16* %Vals, i32* %NumVals), !dbg !221
Broken module found, compilation aborted!
Stack dump:
0. Running pass 'Function Pass Manager' on module 'ld-temp.o'.
1. Running pass 'Module Verifier' on function '@_ZL11EvaluateOpstPtRj'
clang: error: unable to execute command: Illegal instruction: 4
clang: error: linker command failed due to signal (use -v to see invocation)
<rdar://problem/13516485>
llvm-svn: 178156
Rafael Espindola