LTO: whitespace changes

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198954 91177308-0d34-0410-b5e6-96231b3b80d8
Remove remove_all. A compiler has no need for recursively deleting a directory.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198955 91177308-0d34-0410-b5e6-96231b3b80d8
Use the simpler version of sys::fs::remove when possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198958 91177308-0d34-0410-b5e6-96231b3b80d8
All backends use MC now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198959 91177308-0d34-0410-b5e6-96231b3b80d8
Add a note about the old asm printer being removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198960 91177308-0d34-0410-b5e6-96231b3b80d8
Restore the library dependency of LLVMgold on LTO; this was removed recently but
is needed for LLVMgold to load in ld.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198965 91177308-0d34-0410-b5e6-96231b3b80d8
Fixing build break: should be in the if statement, not outside.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198966 91177308-0d34-0410-b5e6-96231b3b80d8
Constant propagate MachineInstrClassName.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198969 91177308-0d34-0410-b5e6-96231b3b80d8
Space formatting fix for r198966.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198971 91177308-0d34-0410-b5e6-96231b3b80d8
Propagation of profile samples through the CFG.

This adds a propagation heuristic to convert instruction samples
into branch weights. It implements a similar heuristic to the one
implemented by Dehao Chen on GCC.

The propagation proceeds in 3 phases:

1- Assignment of block weights. All the basic blocks in the function
   are initial assigned the same weight as their most frequently
   executed instruction.

2- Creation of equivalence classes. Since samples may be missing from
   blocks, we can fill in the gaps by setting the weights of all the
   blocks in the same equivalence class to the same weight. To compute
   the concept of equivalence, we use dominance and loop information.
   Two blocks B1 and B2 are in the same equivalence class if B1
   dominates B2, B2 post-dominates B1 and both are in the same loop.

3- Propagation of block weights into edges. This uses a simple
   propagation heuristic. The following rules are applied to every
   block B in the CFG:

   - If B has a single predecessor/successor, then the weight
     of that edge is the weight of the block.

   - If all the edges are known except one, and the weight of the
     block is already known, the weight of the unknown edge will
     be the weight of the block minus the sum of all the known
     edges. If the sum of all the known edges is larger than B's weight,
     we set the unknown edge weight to zero.

   - If there is a self-referential edge, and the weight of the block is
     known, the weight for that edge is set to the weight of the block
     minus the weight of the other incoming edges to that block (if
     known).

Since this propagation is not guaranteed to finalize for every CFG, we
only allow it to proceed for a limited number of iterations (controlled
by -sample-profile-max-propagate-iterations). It currently uses the same
GCC default of 100.

Before propagation starts, the pass builds (for each block) a list of
unique predecessors and successors. This is necessary to handle
identical edges in multiway branches. Since we visit all blocks and all
edges of the CFG, it is cleaner to build these lists once at the start
of the pass.

Finally, the patch fixes the computation of relative line locations.
The profiler emits lines relative to the function header. To discover
it, we traverse the compilation unit looking for the subprogram
corresponding to the function. The line number of that subprogram is the
line where the function begins. That becomes line zero for all the
relative locations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198972 91177308-0d34-0410-b5e6-96231b3b80d8
Extend and simplify the sample profile input file.

1- Use the line_iterator class to read profile files.

2- Allow comments in profile file. Lines starting with '#'
   are completely ignored while reading the profile.

3- Add parsing support for discriminators and indirect call samples.

   Our external profiler can emit more profile information that we are
   currently not handling. This patch does not add new functionality to
   support this information, but it allows profile files to provide it.

   I will add actual support later on (for at least one of these
   features, I need support for DWARF discriminators in Clang).

   A sample line may contain the following additional information:

   Discriminator. This is used if the sampled program was compiled with
   DWARF discriminator support
   (http://wiki.dwarfstd.org/index.php?title=Path_Discriminators). This
   is currently only emitted by GCC and we just ignore it.

   Potential call targets and samples. If present, this line contains a
   call instruction. This models both direct and indirect calls. Each
   called target is listed together with the number of samples. For
   example,

                    130: 7  foo:3  bar:2  baz:7

   The above means that at relative line offset 130 there is a call
   instruction that calls one of foo(), bar() and baz(). With baz()
   being the relatively more frequent call target.

   Differential Revision: http://llvm-reviews.chandlerc.com/D2355

4- Simplify format of profile input file.

   This implements earlier suggestions to simplify the format of the
   sample profile file. The symbol table is not necessary and function
   profiles do not need to know the number of samples in advance.

   Differential Revision: http://llvm-reviews.chandlerc.com/D2419

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198973 91177308-0d34-0410-b5e6-96231b3b80d8
Fix odd whitespace.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198978 91177308-0d34-0410-b5e6-96231b3b80d8
Update function name and add some helpful comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198979 91177308-0d34-0410-b5e6-96231b3b80d8
Reformat.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198980 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r198979 - accidental commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198981 91177308-0d34-0410-b5e6-96231b3b80d8
[anyregcc] Fix callee-save mask for anyregcc

Use separate callee-save masks for XMM and YMM registers for anyregcc on X86 and
select the proper mask depending on the target cpu we compile for.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198985 91177308-0d34-0410-b5e6-96231b3b80d8
[PM] Add (very skeletal) support to opt for running the new pass
manager. I cannot emphasize enough that this is a WIP. =] I expect it
to change a great deal as things stabilize, but I think its really
important to get *some* functionality here so that the infrastructure
can be tested more traditionally from the commandline.

The current design is looking something like this:

  ./bin/opt -passes='module(pass_a,pass_b,function(pass_c,pass_d))'

So rather than custom-parsed flags, there is a single flag with a string
argument that is parsed into the pass pipeline structure. This makes it
really easy to have nice structural properties that are very explicit.
There is one obvious and important shortcut. You can start off the
pipeline with a pass, and the minimal context of pass managers will be
built around the entire specified pipeline. This makes the common case
for tests super easy:

  ./bin/opt -passes=instcombine,sroa,gvn

But this won't introduce any of the complexity of the fully inferred old
system -- we only ever do this for the *entire* argument, and we only
look at the first pass. If the other passes don't fit in the pass
manager selected it is a hard error.

The other interesting aspect here is that I'm not relying on any
registration facilities. Such facilities may be unavoidable for
supporting plugins, but I have alternative ideas for plugins that I'd
like to try first. My plan is essentially to build everything without
registration until we hit an absolute requirement.

Instead of registration of pass names, there will be a library dedicated
to parsing pass names and the pass pipeline strings described above.
Currently, this is directly embedded into opt for simplicity as it is
very early, but I plan to eventually pull this into a library that opt,
bugpoint, and even Clang can depend on. It should end up as a good home
for things like the existing PassManagerBuilder as well.

There are a bunch of FIXMEs in the code for the parts of this that are
just stubbed out to make the patch more incremental. A quick list of
what's coming up directly after this:
- Support for function passes and building the structured nesting.
- Support for printing the pass structure, and FileCheck tests of all of
  this code.
- The .def-file based pass name parsing.
- IR priting passes and the corresponding tests.

Some obvious things that I'm not going to do right now, but am
definitely planning on as the pass manager work gets a bit further:
- Pull the parsing into library, including the builders.
- Thread the rest of the target stuff into the new pass manager.
- Wire support for the new pass manager up to llc.
- Plugin support.

Some things that I'd like to have, but are significantly lower on my
priority list. I'll get to these eventually, but they may also be places
where others want to contribute:
- Adding nice error reporting for broken pass pipeline descriptions.
- Typo-correction for pass names.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198998 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/test/CodeGen/X86/anyregcc.ll: Add explicit -mtriple=x86_64-unknown-unknown.

XMM(s) are really spilling for targeting Win64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198999 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/test/Transforms/SampleProfile/syntax.ll: Eliminate locale-sensitive message check.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199000 91177308-0d34-0410-b5e6-96231b3b80d8
LoopVectorize.cpp: Appease MSC16.

Excuse me, I hope msc16 builders would be fine till its end day.
Introduce nullptr then. ;)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199001 91177308-0d34-0410-b5e6-96231b3b80d8