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
- This code is dead, and the "right" way to get this support is to use the
platform-specific linker-integrated LTO mechanisms, or the forthcoming LLVM
linker.
llvm-svn: 172749
- Instead of computing a bunch of buckets of different flag types, just do an
incremental link resolving conflicts as they arise.
- This also has the advantage of making the link result deterministic and not
dependent on map iteration order.
llvm-svn: 172634
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.
There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.
The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.
I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).
I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.
llvm-svn: 171366
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
llvm-svn: 169131
The "findUsedStructTypes" method is very expensive to run. It needs to be
optimized so that LTO can run faster. Splitting this method out of the Module
class will help this occur. For instance, it can keep a list of seen objects so
that it doesn't process them over and over again.
llvm-svn: 161228
This allows the user/front-end to specify a model that is better
than what LLVM would choose by default. For example, a variable
might be declared as
@x = thread_local(initialexec) global i32 42
if it will not be used in a shared library that is dlopen'ed.
If the specified model isn't supported by the target, or if LLVM can
make a better choice, a different model may be used.
llvm-svn: 159077
destination module, but one of them isn't used in the destination module. If
another module comes along and the uses the unused type, there could be type
conflicts when the modules are finally linked together. (This happened when
building LLVM.)
The test that was reduced is:
Module A:
%Z = type { %A }
%A = type { %B.1, [7 x x86_fp80] }
%B.1 = type { %C }
%C = type { i8* }
declare void @func_x(%C*, i64, i64)
declare void @func_z(%Z* nocapture)
Module B:
%B = type { %C.1 }
%C.1 = type { i8* }
%A.2 = type { %B.3, [5 x x86_fp80] }
%B.3 = type { %C.1 }
define void @func_z() {
%x = alloca %A.2, align 16
%y = getelementptr inbounds %A.2* %x, i64 0, i32 0, i32 0
call void @func_x(%C.1* %y, i64 37, i64 927) nounwind
ret void
}
declare void @func_x(%C.1*, i64, i64)
declare void @func_y(%B* nocapture)
(Unfortunately, this test doesn't fail under llvm-link, only during an LTO
linking.) The '%C' and '%C.1' clash. The destination module gets the '%C'
declaration. When merging Module B, it looks at the '%C.1' subtype of the '%B'
structure. It adds that in, because that's cool. And when '%B.3' is processed,
it uses the '%C.1'. But the '%B' has used '%C' and we prefer to use '%C'. So the
'@func_x' type is changed to 'void (%C*, i64, i64)', but the type of '%x' in
'@func_z' remains '%A.2'. The GEP resolves to a '%C.1', which conflicts with the
'@func_x' signature.
We can resolve this situation by making sure that the type is used in the
destination before saying that it should be used in the module being merged in.
With this fix, LLVM and Clang both compile under LTO.
<rdar://problem/10913281>
llvm-svn: 153351
Module flags are key-value pairs associated with the module. They include a
'behavior' value, indicating how module flags react when mergine two
files. Normally, it's just the union of the two module flags. But if two module
flags have the same key, then the resulting flags are dictated by the behaviors.
Allowable behaviors are:
Error
Emits an error if two values disagree.
Warning
Emits a warning if two values disagree.
Require
Emits an error when the specified value is not present
or doesn't have the specified value. It is an error for
two (or more) llvm.module.flags with the same ID to have
the Require behavior but different values. There may be
multiple Require flags per ID.
Override
Uses the specified value if the two values disagree. It
is an error for two (or more) llvm.module.flags with the
same ID to have the Override behavior but different
values.
llvm-svn: 150300
the build bot in some cases. The basic issue happens when a source module contains
both a "%foo" type and a "%foo.42" type. It will see the later one, check to see if
the destination module contains a "%foo" type, and it will return true... because
both the source and destination modules are in the same LLVMContext. We don't want
to map source types to other source types, so don't do the remapping if the mapped
type came from the source module.
Unfortunately, I've been unable to reduce a decent testcase for this, kc++ is
pretty great that way.
llvm-svn: 147010
merging types by name when we can. We still don't guarantee type name linkage
but we do it when obviously the right thing to do. This makes LTO type names
easier to read, for example.
llvm-svn: 146932
internal nightly testers. Original commit message:
By popular demand, link up types by name if they are isomorphic and one is an
autorenamed version of the other. This makes the IR easier to read, because
we don't end up with random renamed versions of the types after LTO'ing a large
app.
llvm-svn: 146838
autorenamed version of the other. This makes the IR easier to read, because
we don't end up with random renamed versions of the types after LTO'ing a large app.
llvm-svn: 146728
This line, and those below, will be ignored--
M include/llvm/Linker.h
M tools/bugpoint/Miscompilation.cpp
M tools/bugpoint/BugDriver.cpp
M tools/llvm-link/llvm-link.cpp
M lib/Linker/LinkModules.cpp
llvm-svn: 141606
It happens (for example) when you want to have a dependency on the .so
with the specific version, like liblzma.so.1.0.0 or
libcrypto.so.0.9.8.
llvm-svn: 140201