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
signal handlers to prevent reentrance on unrelated things (a sigabort
where the handle bus errors) also, clear the signal mask so that the
signal doesn't infinitely reissue. This fixes rdar://6654827 -
Crash causes clang to loop
llvm-svn: 66330
1. When the JIT is asked to remove a function, updating it's
mapping to 0, we invalidate any function stubs used only
by that function. Now, also invalidate the JIT's mapping
from the GV the stub pointed to, to the address of the GV.
2. When dlsym stubs for cross-process JIT are enabled, do not
abort just because a named function cannot be found in the
JIT's process.
3. Fix various assumptions about when it is ok to use the lazy
resolver when non-lazy JITing is enabled.
llvm-svn: 66324
on all the new code by default. There is still plenty of testing to
do and issues I'm sure need resolving. Let me know if you find
anything.
llvm-svn: 66323
performance that the type of the returned llvm::Value for an expression
matches the converted type of the clang::Expr; mismatches will cause all
sorts of errors and silent miscompilations.
llvm-svn: 66321
the same say the "test" instruction does in overflow cases,
so eliminating the test is only safe when those bits aren't
needed, as is the case for COND_E and COND_NE, or if it
can be proven that no overflow will occur. For now, just
restrict the optimization to COND_E and COND_NE and don't
do any overflow analysis.
llvm-svn: 66318
- Shaves off a few instructions on x86_64.
One notable change: this intentionally stops setting the II->Entry
field of IdentifierInfo's retrieved by the ExternalLookup method. This
is to maintain the invariant that .getName() has a constant value for
any given IdentifierInfo. IRgen currently relies on this; which is
quite questionable but will be cleaned up in time.
Apologies for the lack of a test case; there really isn't a good way
to make one. As IRgen will eventually be fixed to not rely on this, we
can survive without one.
llvm-svn: 66316
- Make Selector::getAsIdentifierInfo() private. Using IdentifierInfo* in
Selector is an implementation detail that clients shouldn't think about.
- Modify diagnostic emission in Sema::ProcessPropertyDecl to not use
Selector::getAsIdentifierInfo() (which could crash when IdentifierInfo* is
null) and instead use Selector::getAsString().
- Tidy up Selector::getAsString() implementation.
llvm-svn: 66313
PathDiagnosticControlFlowPiece to distinguish (in the class hierarchy) between
events and control-flow diagnostic pieces. Clients must now use these directly
when constructing PathDiagnosticPieces.
llvm-svn: 66310