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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211920 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210302 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210062 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209007 91177308-0d34-0410-b5e6-96231b3b80d8
This is part of the fix for pr10367. A GlobalAlias always has a pointer type,
so just have the constructor build the type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208983 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208716 91177308-0d34-0410-b5e6-96231b3b80d8
`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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208262 91177308-0d34-0410-b5e6-96231b3b80d8
The fact that GlobalAlias::setAlignment exists at all is a side effect of
how the classes are organized, it should never be used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208094 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes spurious warnings in llvm-link about the datalayout not matching.
Thanks to Zalman Stern for reporting the bug!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202276 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202190 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201819 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199354 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199218 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199204 91177308-0d34-0410-b5e6-96231b3b80d8
This would cause internal symbols that are only referenced by global initializers to be removed.
This reverts commit 194219.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194304 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194218 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192778 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189935 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182776 91177308-0d34-0410-b5e6-96231b3b80d8
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!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181104 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181099 91177308-0d34-0410-b5e6-96231b3b80d8
The linker is now responsible only for actually linking the modules, it
is up to the clients to create and destroy them.
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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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180881 91177308-0d34-0410-b5e6-96231b3b80d8
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>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178156 91177308-0d34-0410-b5e6-96231b3b80d8
