[mips] Correct lowering of VECTOR_SHUFFLE to VSHF.

Summary:
VECTOR_SHUFFLE concatenates the vectors in an vectorwise fashion.
  <0b00, 0b01> + <0b10, 0b11> -> <0b00, 0b01, 0b10, 0b11>
VSHF concatenates the vectors in a bitwise fashion:
  <0b00, 0b01> + <0b10, 0b11> ->
  0b0100       + 0b1110       -> 0b01001110
                                 <0b10, 0b11, 0b00, 0b01>
We must therefore swap the operands to get the correct result.

The test case that discovered the issue was MultiSource/Benchmarks/nbench.

Reviewers: matheusalmeida

Reviewed By: matheusalmeida

Differential Revision: http://llvm-reviews.chandlerc.com/D3142

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204480 91177308-0d34-0410-b5e6-96231b3b80d8
Split out the MC part of this test.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204481 91177308-0d34-0410-b5e6-96231b3b80d8
ProfileData: Introduce the InstrProfReader interface and a text reader

This introduces the ProfileData library and updates llvm-profdata to
use this library for reading profiles. InstrProfReader is an abstract
base class that will be subclassed for both the raw instrprof data
from compiler-rt and the efficient instrprof format that will be used
for PGO.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204482 91177308-0d34-0410-b5e6-96231b3b80d8
Remove redundant test.

The production of the .eh symbols is done from MC now and we already have tests
for it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204483 91177308-0d34-0410-b5e6-96231b3b80d8
llvm-profdata: Implement show command

The `llvm-profdata show` command summarizes a profdata file's contents
in a human readable format.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204485 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor llvm/test/lit.cfg to use lit.util.which.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204486 91177308-0d34-0410-b5e6-96231b3b80d8
Convert test to using cfi.

An unnamed global in llvm still produces a regular symbol.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204488 91177308-0d34-0410-b5e6-96231b3b80d8
ProfileData: Introduce InstrProfWriter using the naive text format

This isn't a format we'll want to write out in practice, but moving it
to the writer library simplifies llvm-profdata and isolates it from
further changes to the format.

This also allows us to update the tests to not rely on the text output
format.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204489 91177308-0d34-0410-b5e6-96231b3b80d8