metadata types which should be marked as "weak", but which the linker will
remove upon final linkage. For example, the "objc_msgSend_fixup_alloc" symbol is
defined like this:

       .globl l_objc_msgSend_fixup_alloc
       .weak_definition l_objc_msgSend_fixup_alloc
       .section __DATA, __objc_msgrefs, coalesced
       .align 3
l_objc_msgSend_fixup_alloc:
        .quad   _objc_msgSend_fixup
        .quad   L_OBJC_METH_VAR_NAME_1

This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".

llvm-svn: 107205

methods to try to have the type predicates be more logically positioned.

llvm-svn: 96349

llvm-svn: 95468

Need to recurse for all operands of function-local metadata; and handle Instructions (which map to themselves)

llvm-svn: 94691

llvm-svn: 94650

llvm-svn: 94632

llvm-svn: 94243

Fixed linking of modules containing aliases to constant bitcasts.  Existing behaviour first tried to replace the aliases with the global that they aliased (rather than the bitcast), causing a crash on an assert because the types didn't match.  When this was fixed, it then did the same thing creating the new alias (creating an alias with a different type to its aliasee).  

Linking modules containing aliases to GEPs is still not quite right.  GEPs that are equivalent to bitcasts will be replaced by bitcasts, GEPs that are not will just break.  Aliases to GEPs that are not equivalent to bitcasts are horribly broken anyway (it might be worth adding an assert when creating the alias to prevent these being created; they just cause problems later).

llvm-svn: 93052

llvm-svn: 92628

things that occur in types.  "operands" are things that occur
in values.

llvm-svn: 92322

llvm-svn: 92192

llvm-svn: 85700

llvm-svn: 81636

llvm-svn: 80941

forcing them down into various .cpp files.

This change also:
1. Renames TimeValue::toString() and Path::toString() to ::str()
   for similarity with the STL.
2. Removes all stream insertion support for sys::Path, forcing
   clients to call .str().
3. Removes a use of Config/alloca.h from bugpoint, using smallvector
   instead.
4. Weans llvm-db off <iostream>

sys::Path really needs to be gutted, but I don't have the desire to
do it at this point.

llvm-svn: 79869

This required converting a bunch of stuff off DOUT and other cleanups.

llvm-svn: 79819

llvm-svn: 78696

llvm-svn: 78652

metadata related, which I'm waiting on to avoid conflicting with Devang.

llvm-svn: 77721

llvm-svn: 77516

llvm-svn: 77495

llvm-svn: 77494

llvm-svn: 77366

llvm-svn: 77347

llvm-svn: 77266

Also, change MDString to use a StringRef.

llvm-svn: 77098

 - The only meat here is in Value.{h,cpp} the rest is essential 'const
   std::string &' -> 'const Twine &'.

llvm-svn: 77048

llvm-svn: 76894

llvm-svn: 76702

"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

This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").

llvm-svn: 75640

Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.

llvm-svn: 75379

llvm-svn: 75025

llvm-svn: 74985

llvm-svn: 74948

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

final cleaning.  This fixes a bunch of testsuite failures.

llvm-svn: 66380

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

llvm-svn: 65942

llvm-svn: 65936