"private" symbols which the assember shouldn't strip, but which the linker may
remove after evaluation. This is mostly useful for Objective-C metadata.
This is plumbing, so we don't have a use of it yet. More to come, etc.
llvm-svn: 76385
create separate recursive mutexes for each value map. The recursive-ness fixes the double-acquiring issue, which having one per ValueMap
lets us continue to maintain some concurrency.
llvm-svn: 73801
gets involved, and we end up trying to recursively acquire a writer lock. The fix for this is slightly horrible,
and involves passing a boolean "locked" parameter around in Constants.cpp, but it's better than having locked and
unlocked versions of most of the code.
llvm-svn: 73790
and it wasn't generating calls through @PLT for these functions.
hasLocalLinkage() is now false for available_externally,
I attempted to fix the inliner and dce to handle available_externally properly.
It passed make check.
llvm-svn: 72328
to support C99 inline, GNU extern inline, etc. Related bugzilla's
include PR3517, PR3100, & PR2933. Nothing uses this yet, but it
appears to work.
llvm-svn: 68940
and extern_weak_odr. These are the same as the non-odr versions,
except that they indicate that the global will only be overridden
by an *equivalent* global. In C, a function with weak linkage can
be overridden by a function which behaves completely differently.
This means that IP passes have to skip weak functions, since any
deductions made from the function definition might be wrong, since
the definition could be replaced by something completely different
at link time. This is not allowed in C++, thanks to the ODR
(One-Definition-Rule): if a function is replaced by another at
link-time, then the new function must be the same as the original
function. If a language knows that a function or other global can
only be overridden by an equivalent global, it can give it the
weak_odr linkage type, and the optimizers will understand that it
is alright to make deductions based on the function body. The
code generators on the other hand map weak and weak_odr linkage
to the same thing.
llvm-svn: 66339
the section or the visibility from one global
value to another: copyAttributesFrom. This is
particularly useful for duplicating functions:
previously this was done by explicitly copying
each attribute in turn at each place where a
new function was created out of an old one, with
the result that obscure attributes were regularly
forgotten (like the collector or the section).
Hopefully now everything is uniform and nothing
is forgotten.
llvm-svn: 51567
are represented as "weak", but there are subtle differences
in some cases on Darwin, so we need both. The intent
is that "common" will behave identically to "weak" unless
somebody changes their target to do something else.
No functional change as yet.
llvm-svn: 51118
_sabre_: it has a major problem: by the time ~Value is run, all of the "parts" of the derived classes have been destroyed
_sabre_: the vtable lives to fight another day
llvm-svn: 44760
field into SubclassData in Value. This shrinks GlobalVAlue from 48->40
bytes, Function from 88->76, and GlobalVariable from 76->68. This trims
4640 bytes off my testcase, reading a bc file without materializing any
functions.
llvm-svn: 36192
exprs hanging off a global, even if the global is not otherwise dead. This
requires some tricky iterator gymnastics.
This implements Transforms/GlobalOpt/constantexpr-dangle.ll by deleting a
constantexpr that made it appear that the address of the function was taken.
llvm-svn: 34608
as its main datastructure. There are many improvements yet to be made, but
this speeds up opt --std-compile-opts on 447.dealII by 7.3%.
llvm-svn: 34193
* PIC-aware internal structures in X86 Codegen have been refactored
* Visibility (default/weak) has been added
* Docs fixes (external weak linkage, visibility, formatting)
llvm-svn: 33136
DLL* linkages got full (I hope) codegeneration support in C & both x86
assembler backends.
External weak linkage added for future use, we don't provide any
codegeneration, etc. support for it.
llvm-svn: 30374