Commit Graph

4504 Commits

Author SHA1 Message Date
Bill Wendling
167ede898a Reverting r171325 & r172363. This was causing a mis-compile on the self-hosted LTO build bots.
Okay, here's how to reproduce the problem:

1) Build a Release (or Release+Asserts) version of clang in the normal way.

2) Using the clang & clang++ binaries from (1), build a Release (or
   Release+Asserts) version of the same sources, but this time enable LTO ---
   specify the `-flto' flag on the command line.

3) Run the ARC migrator tests:

    $ arcmt-test --args -triple x86_64-apple-darwin10 -fsyntax-only -x objective-c++ ./src/tools/clang/test/ARCMT/cxx-rewrite.mm

You'll see that the output isn't correct (the whitespace is off).

The mis-compile is in the function `RewriteBuffer::RemoveText' in the
clang/lib/Rewrite/Core/Rewriter.cpp file. When that function and RewriteRope.cpp
are compiled with LTO and the `arcmt-test' executable is regenerated, you'll see
the error. When those files are not LTO'ed, then the output of the `arcmt-test'
is fine.

It is *really* hard to get a testcase out of this. I'll file a PR with what I
have currently.

--- Reverse-merging r172363 into '.':
U    include/llvm/Analysis/MemoryBuiltins.h
U    lib/Analysis/MemoryBuiltins.cpp

--- Reverse-merging r171325 into '.':
U    test/Transforms/InstCombine/objsize.ll
G    include/llvm/Analysis/MemoryBuiltins.h
G    lib/Analysis/MemoryBuiltins.cpp




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172756 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-17 21:28:46 +00:00
Renato Golin
d3c965d625 Change CostTable model to be global to all targets
Moving the X86CostTable to a common place, so that other back-ends
can share the code. Also simplifying it a bit and commoning up
tables with one and two types on operations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172658 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-16 21:29:55 +00:00
Andrew Trick
1ba5769676 SCEVExpander fix. RAUW needs to update the InsertedExpressions cache.
Note that this bug is only exposed because LTO fails to use TTI.

Fixes self-LTO of clang. rdar://13007381.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172462 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-14 21:00:37 +00:00
Nuno Lopes
29eb2cc00c fix compile-time regression report by Joerg Sonnenberger:
cache result of Size/OffsetVisitor to speedup analysis of PHI nodes

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172363 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-13 18:02:57 +00:00
Dmitri Gribenko
96f498bd9f Remove redundant 'llvm::' qualifications
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172358 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-13 16:01:15 +00:00
Andrew Trick
74c1be27a4 Update CMakeLists for CallPrinter.cpp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172222 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-11 17:34:05 +00:00
Andrew Trick
a125cacf7d Added -view-callgraph module pass.
-dot-callgraph similarly follows a standard module pass pattern.

Patch by Speziale Ettore!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172220 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-11 17:28:14 +00:00
Nadav Rotem
14925e6b88 ARM Cost model: Use the size of vector registers and widest vectorizable instruction to determine the max vectorization factor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172010 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 22:29:00 +00:00
Nadav Rotem
83be7b0dd3 Cost Model: Move the 'max unroll factor' variable to the TTI and add initial Cost Model support on ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171928 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09 01:15:42 +00:00
Chandler Carruth
3251e81d79 Move CallGraphSCCPass.h into the Analysis tree; that's where the
implementation lives already.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171746 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 15:26:48 +00:00
Chandler Carruth
e4ba75f43e Switch the SCEV expander and LoopStrengthReduce to use
TargetTransformInfo rather than TargetLowering, removing one of the
primary instances of the layering violation of Transforms depending
directly on Target.

This is a really big deal because LSR used to be a "special" pass that
could only be tested fully using llc and by looking at the full output
of it. It also couldn't run with any other loop passes because it had to
be created by the backend. No longer is this true. LSR is now just
a normal pass and we should probably lift the creation of LSR out of
lib/CodeGen/Passes.cpp and into the PassManagerBuilder. =] I've not done
this, or updated all of the tests to use opt and a triple, because
I suspect someone more familiar with LSR would do a better job. This
change should be essentially without functional impact for normal
compilations, and only change behvaior of targetless compilations.

The conversion required changing all of the LSR code to refer to the TTI
interfaces, which fortunately are very similar to TargetLowering's
interfaces. However, it also allowed us to *always* expect to have some
implementation around. I've pushed that simplification through the pass,
and leveraged it to simplify code somewhat. It required some test
updates for one of two things: either we used to skip some checks
altogether but now we get the default "no" answer for them, or we used
to have no information about the target and now we do have some.

I've also started the process of removing AddrMode, as the TTI interface
doesn't use it any longer. In some cases this simplifies code, and in
others it adds some complexity, but I think it's not a bad tradeoff even
there. Subsequent patches will try to clean this up even further and use
other (more appropriate) abstractions.

Yet again, almost all of the formatting changes brought to you by
clang-format. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171735 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 14:41:08 +00:00
Chandler Carruth
6554666e00 Move the initialization to the Analysis library as well as the pass.
This was (somewhat distressingly) only caught be the ocaml bindings
tests...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171690 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 03:33:08 +00:00
Chandler Carruth
d1b8ef97c4 Make the popcnt support enums and methods have more clear names and
follow the conding conventions regarding enumerating a set of "kinds" of
things.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171687 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 03:16:03 +00:00
Chandler Carruth
be04929f7f Move TargetTransformInfo to live under the Analysis library. This no
longer would violate any dependency layering and it is in fact an
analysis. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171686 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-07 03:08:10 +00:00
Chandler Carruth
194bd71b06 Switch the cost model analysis over to just the TTI interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171619 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-05 10:09:33 +00:00
Manman Ren
c55bd47105 Memory Dependence Analysis: fix a miscompile that uses DT to approxmiate the
reachablity.

We conservatively approximate the reachability analysis by saying it is not
reachable if there is a single path starting from "From" and the path does not
reach "To".

rdar://12801584


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171512 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-04 19:19:47 +00:00
Chandler Carruth
351ba145a7 Actually update the CMake and Makefile builds correctly, and update the
code that includes Intrinsics.gen directly.

This never showed up in my testing because the old Intrinsics.gen was
still kicking around in the make build system and was correct there. =[
Thankfully, some of the bots to clean rebuilds and that caught this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171373 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 12:09:16 +00:00
Chandler Carruth
0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00
Chandler Carruth
c2c50cdcdc Rename VMCore directory to IR.
Aside from moving the actual files, this patch only updates the build
system and the source file comments under lib/... that are relevant.

I'll be updating other docs and other files in smaller subsequnet
commits.

While I've tried to test this, but it is entirely possible that there
will still be some build system fallout.

Also, note that I've not changed the library name itself: libLLVMCore.a
is still the library name. I'd be interested in others' opinions about
whether we should rename this as well (I think we should, just not sure
what it might break)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171359 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 09:10:48 +00:00
Nuno Lopes
5cec34754d reimplement GetPointerBaseWithConstantOffset().
The new code is an improved copy of the code I deleted from Analysis/Loads.cpp.
One less compute-constant-gep-offset implementation. yay :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171326 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 20:48:35 +00:00
Nuno Lopes
0a9ff4cab3 recommit r171298 (add support for PHI nodes to ObjectSizeOffsetVisitor). Hopefully with bugs corrected now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171325 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 20:45:10 +00:00
Benjamin Kramer
44365353a4 Revert "add support for PHI nodes to ObjectSizeOffsetVisitor"
This reverts r171298. Breaks clang selfhost.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171318 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 19:51:10 +00:00
Nuno Lopes
2e594fa85c revert r171306, since we cannot compare APInts with different bitwidths
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171308 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 18:01:36 +00:00
Nuno Lopes
1ef05b1a2a use ValueTracking's GetPointerBaseWithConstantOffset() function instead of a local implementation
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171307 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 17:42:11 +00:00
Nuno Lopes
a44766a4dd minor code simplification
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171306 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 17:25:24 +00:00
Nuno Lopes
41be2fb1f9 add support for GlobalAlias to ObjectSizeOffsetVisitor
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171303 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 16:23:48 +00:00
Nuno Lopes
729e602082 add support for PHI nodes to ObjectSizeOffsetVisitor
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171298 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-31 13:52:36 +00:00
Nuno Lopes
98281a2050 convert a bunch of callers from DataLayout::getIndexedOffset() to GEP::accumulateConstantOffset().
The later API is nicer than the former, and is correct regarding wrap-around offsets (if anyone cares).
There are a few more places left with duplicated code, which I'll remove soon.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171259 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-30 16:25:48 +00:00
Bill Wendling
831737d329 Remove the Function::getFnAttributes method in favor of using the AttributeSet
directly.

This is in preparation for removing the use of the 'Attribute' class as a
collection of attributes. That will shift to the AttributeSet class instead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171253 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-30 10:32:01 +00:00
Chandler Carruth
a84e7508eb Nuke some dead code that snuck in some how. I thought I had already
deleted this, but apparantly not. Charmingly, Clang didn't warn on it
but GCC did.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171197 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 14:50:51 +00:00
Chandler Carruth
73527d30cd Fix a stunning oversight in the inline cost analysis. It was never
propagating one of the values it simplified to a constant across
a myriad of instructions. Notably, ptrtoint instructions when we had
a constant pointer (say, 0) didn't propagate that, blocking a massive
number of down-stream optimizations.

This was uncovered when investigating why we fail to inline and delete
the boilerplate in:

  void f() {
    std::vector<int> v;
    v.push_back(1);
  }

It turns out most of the efforts I've made thus far to improve the
analysis weren't making it far purely because of this. After this is
fixed, the store-to-load forwarding patch enables LLVM to optimize the
above to an empty function. We still can't nuke a second push_back, but
for different reasons.

There is a very real chance this will cause somewhat noticable changes
in inlining behavior, so please let me know if you see regressions (or
improvements!) because of this patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171196 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 14:43:42 +00:00
Chandler Carruth
ba94204e94 Teach the inline cost analysis about calls that can be simplified and
how to propagate constants through insert and extract value
instructions.

With the recent improvements to instsimplify, this allows inline cost
analysis to constant fold through intrinsic functions, including notably
the with.overflow intrinsic math routines which often show up inside of
STL abstractions. This is yet another piece in the puzzle of breaking
down the code for:

  void f() {
    std::vector<int> v;
    v.push_back(1);
  }

But it still isn't enough. There are a pile of bugs in inline cost still
blocking this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171195 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 14:23:32 +00:00
Chandler Carruth
e949aa1c91 Teach instsimplify to use the constant folder where appropriate for
constant folding calls. Add the initial tests for this which show that
now instsimplify can simplify blindingly obvious code patterns expressed
with both intrinsics and library calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171194 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 14:23:29 +00:00
Chandler Carruth
c98bd9f1a7 Add entry points to instsimplify for simplifying calls. The entry points
are nice and decomposed so that we can simplify synthesized calls as
easily as actually call instructions. The internal utility still has the
same behavior, it just now operates on a more generic interface so that
I can extend the set of call simplifications that instsimplify knows
about.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171189 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 11:30:55 +00:00
Bob Wilson
a0be09f511 Add LLVMContext::emitWarning methods and use them. <rdar://problem/12867368>
When the backend is used from clang, it should produce proper diagnostics
instead of just printing messages to errs(). Other clients may also want to
register their own error handlers with the LLVMContext, and the same handler
should work for warnings in the same way as the existing emitError methods.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171041 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-24 18:15:21 +00:00
Nadav Rotem
99b7a99376 Update the docs of the cost model.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171016 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-24 05:51:12 +00:00
Craig Topper
c4265e1d68 Remove trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170991 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-22 19:15:35 +00:00
James Molloy
67ae135759 Add a new attribute, 'noduplicate'. If a function contains a noduplicate call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call.
Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170704 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 16:04:27 +00:00
Nadav Rotem
521396ab37 Fix a bug that was found by building clang with -fsanitize.
I introduced it in r166785. PR14291.

If TD is unavailable use getScalarSizeInBits, but don't optimize
pointers or vectors of pointers.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170586 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 20:47:04 +00:00
Bill Wendling
034b94b170 Rename the 'Attributes' class to 'Attribute'. It's going to represent a single attribute in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170502 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-19 07:18:57 +00:00
Nadav Rotem
fd360c3e24 Fix a crash in ValueTracking on vectors of pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170240 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-14 20:43:49 +00:00
Rafael Espindola
dbaa2376f7 Rename isPowerOfTwo to isKnownToBeAPowerOfTwo.
In a previous thread it was pointed out that isPowerOfTwo is not a very precise
name since it can return false for powers of two if it is unable to show that
they are powers of two.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170093 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-13 03:37:24 +00:00
Rafael Espindola
b09c146b11 The TargetData is not used for the isPowerOfTwo determination. It has never
been used in the first place.  It simply was passed to the function and to the
recursive invocations.  Simply drop the parameter and update the callers for the
new signature.

Patch by Saleem Abdulrasool!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169988 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 16:52:40 +00:00
Michael Ilseman
d0a0d221da Have SimplifyBinOp call the new FAdd/FSub/FMul helpers, with fast-math flags off
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169943 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:29:16 +00:00
Michael Ilseman
09ee250e72 Added a slew of SimplifyInstruction floating-point optimizations, many of which take advantage of fast-math flags. Test cases included.
fsub X, +0 ==> X
  fsub X, -0 ==> X, when we know X is not -0
  fsub +/-0.0, (fsub -0.0, X) ==> X
  fsub nsz +/-0.0, (fsub +/-0.0, X) ==> X
  fsub nnan ninf X, X ==> 0.0
  fadd nsz X, 0 ==> X
  fadd [nnan ninf] X, (fsub [nnan ninf] 0, X) ==> 0
    where nnan and ninf have to occur at least once somewhere in this expression
  fmul X, 1.0 ==> X



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169940 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 00:27:46 +00:00
Chandler Carruth
7550f96b2f Holding my nose and moving the accumulation routine to GEPOperator
instead of the instruction. I've left a forwarding wrapper for the
instruction so users with the instruction don't need to create
a GEPOperator themselves.

This lets us remove the copy of this code in instsimplify.

I've looked at most of the other copies of similar code, and this is the
only one I've found that is actually exactly the same. The one in
InlineCost is very close, but it requires re-mapping non-constant
indices through the cost analysis value simplification map. I could add
direct support for this to the generic routine, but it seems overly
specific.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169853 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-11 11:05:15 +00:00
Chandler Carruth
4ced4ee94b Hoist the GEP constant address offset computation to a common home on
the GEP instruction class.

This is part of the continued refactoring and cleaning of the
infrastructure used by SROA. This particular operation is also done in
a few other places which I'll try to refactor to share this
implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169852 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-11 10:29:10 +00:00
Arnold Schwaighofer
2b475922e6 Optimistically analyse Phi cycles
Analyse Phis under the starting assumption that they are NoAlias. Recursively
look at their inputs.
If they MayAlias/MustAlias there must be an input that makes them so.

Addresses bug 14351.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169788 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-10 23:02:41 +00:00
Chandler Carruth
ed90ed077a Add a new visitor for walking the uses of a pointer value.
This visitor provides infrastructure for recursively traversing the
use-graph of a pointer-producing instruction like an alloca or a malloc.
It maintains a worklist of uses to visit, so it can handle very deep
recursions. It automatically looks through instructions which simply
translate one pointer to another (bitcasts and GEPs). It tracks the
offset relative to the original pointer as long as that offset remains
constant and exposes it during the visit as an APInt offset. Finally, it
performs conservative escape analysis.

However, currently it has some limitations that should be addressed
going forward:
1) It doesn't handle vectors of pointers.
2) It doesn't provide a cheaper visitor when the constant offset
   tracking isn't needed.
3) It doesn't support non-instruction pointer values.

The current functionality is exactly what is required to implement the
SROA pointer-use visitors in terms of this one, rather than in terms of
their own ad-hoc base visitor, which was always very poorly specified.
SROA has been converted to use this, and the code there deleted which
this utility now provides.

Technically speaking, using this new visitor allows SROA to handle a few
more cases than it previously did. It is now more aggressive in ignoring
chains of instructions which look like they would defeat SROA, but in
fact do not because they never result in a read or write of memory.
While this is "neat", it shouldn't be interesting for real programs as
any such chains should have been removed by others passes long before we
get to SROA. As a consequence, I've not added any tests for these
features -- it shouldn't be part of SROA's contract to perform such
heroics.

The goal is to extend the functionality of this visitor going forward,
and re-use it from passes like ASan that can benefit from doing
a detailed walk of the uses of a pointer.

Thanks to Ben Kramer for the code review rounds and lots of help
reviewing and debugging this patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169728 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-10 08:28:39 +00:00
Michael Ilseman
1638b83909 Reorganize FastMathFlags to be a wrapper around unsigned, and streamline some interfaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169712 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-09 21:12:04 +00:00