Fix a typo, in a comment, in a test.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192632 91177308-0d34-0410-b5e6-96231b3b80d8
whitespace

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192633 91177308-0d34-0410-b5e6-96231b3b80d8
LiveRegUnits: Use *MBB for consistency and convenience.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192634 91177308-0d34-0410-b5e6-96231b3b80d8
Fix the ExecutionDepsFix pass to handle AVX instructions.

This pass is needed to break false dependencies. Without it, unlucky
register assignment can result in wild (5x) swings in
performance. This pass was trying to handle AVX but not getting it
right. AVX doesn't have partial register defs, it has unused register
reads in which the high bits of a source operand are copied into the
unused bits of the dest.

Fixing this requires conservative liveness analysis. This is awkard
because the pass already has its own pseudo-liveness. However, proper
liveness is expensive, and we would like to use a generic utility to
compute it. The fix only invokes liveness on-demand. It is rare to
detect a case that needs undef-read dependence breaking, but when it
happens, it can be needed many times within a very large block.

I think the existing heuristic which uses a register window of 16 is
too conservative for loop-carried false dependencies. If the loop is a
reduction. The out-of-order engine may be able to execute several loop
iterations in parallel. However, I'll leave this tuning exercise for
next time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192635 91177308-0d34-0410-b5e6-96231b3b80d8
[X86][FastISel] During X86 fastisel, the address of indirect call was resolved
through bitcast, ptrtoint, and inttoptr instructions. This is valid
only if the related instructions are in that same basic block, otherwise
we may reference variables that were not live accross basic blocks
resulting in undefined virtual registers.

The bug was exposed when both SDISel and FastISel were used within the same
function, i.e., one basic block is issued with FastISel and another with SDISel,
as demonstrated with the testcase.

<rdar://problem/15192473>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192636 91177308-0d34-0410-b5e6-96231b3b80d8
Update comment list of GLOBALVAR modifiers in BitcodeWriter to include externally_initialized.

Thanks to Shuxin Yang for catching this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192637 91177308-0d34-0410-b5e6-96231b3b80d8