For use with -headers, -yaml-only will cause cpp11-migrate to not write header
changes to disk and instead write them as header change description files. This
option facilitiates upcoming functionality to properly support changing headers
as part of migration.
Differential Revision: http://llvm-reviews.chandlerc.com/D1385
llvm-svn: 188371
It's useful to be able to write down floating-point numbers without having to
worry about what they'll be rounded to (as C99 discovered), this extends that
ability to the MC assembly parsers.
llvm-svn: 188370
This change moves everything depending on kernel headers (mostly ioctl types
and ids) into a separate source file. This will reduce the possibility of
header conflict on various platforms (most importantly, older glibc versions).
This change also removes 2 deprecated ioctls, and symbolic ids for other bunch
of ambiguous ioctls (i.e. same id is shared by ioctls with different memory
behavior).
llvm-svn: 188369
extremely subtle miscompilations (such as a load getting replaced with
the value stored *below* the load within a basic block) related to
promoting an alloca to an SSA value, there is the dim possibility that
you hit this. Please let me know if you won this unfortunate lottery.
The first half of mem2reg's core logic (as it is used both in the
standalone mem2reg pass and in SROA) builds up a mapping from
'Instruction *' to the index of that instruction within its basic block.
This allows quickly establishing which store dominate a particular load
even for large basic blocks. We cache this information throughout the
run of mem2reg over a function in order to amortize the cost of
computing it.
This is not in and of itself a strange pattern in LLVM. However, it
introduces a very important constraint: absolutely no instruction can be
deleted from the program without updating the mapping. Otherwise a newly
allocated instruction might get the same pointer address, and then end
up with a wrong index. Yes, LLVM routinely suffers from a *single
threaded* variant of the ABA problem. Most places in LLVM don't find
avoiding this an imposition because they don't both delete and create
new instructions iteratively, but mem2reg *loves* to do this... All the
time. Fortunately, the mem2reg code was really careful about updating
this cache to handle this eventuallity... except when it comes to the
debug declare intrinsic. Oops. The fix is to invalidate that pointer in
the cache when we delete it, the same as we do when deleting alloca
instructions and other instructions.
I've also caused the same bug in new code while working on a fix to
PR16867, so this seems to be a really unfortunate pattern. Hopefully in
subsequent patches the deletion of dead instructions can be consolidated
sufficiently to make it less likely that we'll see future occurences of
this bug.
Sorry for not having a test case, but I have literally no idea how to
reliably trigger this kind of thing. It may be single-threaded, but it
remains an ABA problem. It would require a really amazing number of
stars to align.
llvm-svn: 188367
The rationale for this change is to differentiate following two situations:
1) clang -c -emit-llvm a.c
2) clang -c -flto a.c
Reviewed by Eric Christopher. Thanks a lot!
llvm-svn: 188352
Use the pointer size if datalayout is available.
Use i64 if it's not, which is consistent with what other
places do when the pointer size is unknown.
The test doesn't really test this in a useful way
since it will be transformed to that later anyway,
but this now tests it for non-zero arrays and when
datalayout isn't available. The cases in
visitGetElementPtrInst should save an extra re-visit to
the newly created GEP since it won't need to cleanup after
itself.
llvm-svn: 188339
This adds support for the /link option, which forwards
subsequent arguments to the linker.
The test for this will only work when targetting win32.
Since that's the only target where clang-cl makes sense,
use that target by default.
Differential Revision: http://llvm-reviews.chandlerc.com/D1388
llvm-svn: 188331
It doesn't make any sense to accept "..." in the argument to a C-style cast,
so use a separate expression list parsing routine which rejects it. PR16874.
llvm-svn: 188330
When computing the use set of a store, we need to add the store to the write
set prior to iterating over later instructions. Otherwise, if there is a later
aliasing load of that store, that load will not be tagged as a use, and bad
things will happen.
trackUsesOfI still adds later dependent stores of an instruction to that
instruction's write set, but it never sees the original instruction, and so
when tracking uses of a store, the store must be added to the write set by the
caller.
Fixes PR16834.
llvm-svn: 188329
However, opt -O2 doesn't run mem2reg directly so nobody noticed until r188146
when SROA started sending more things directly down the PromoteMemToReg path.
In order to revert r187191, I also revert dependent revisions r187296, r187322
and r188146. Fixes PR16867. Does not add the testcases from that PR, but both
of them should get added for both mem2reg and sroa when this revert gets
unreverted.
llvm-svn: 188327
Marshall Clow