Fixed tryFoldToZero() for vector types that need expansion.

Summary:
Moved the requirement for SelectionDAG::getConstant() to return legally
typed nodes slightly earlier. There were two optional DAGCombine passes
that were missed out and were required to produce type-legal DAGs.

Simplified a code-path in tryFoldToZero() to use SelectionDAG::getConstant().
This provides support for both promoted and expanded vector types whereas the
previous code only supported promoted vector types.

Fixes a "Type for zero vector elements is not legal" assertion detected by
an llvm-stress generated test.

Reviewers: resistor

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2251

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195635 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r195599 as it broke the builds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195636 91177308-0d34-0410-b5e6-96231b3b80d8
[ARM] Enable FeatureMP for Cortex-A5 by default.

Patch by Oliver Stannard.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195640 91177308-0d34-0410-b5e6-96231b3b80d8
ARM: remove unused patterns.

There is no sane way for an LEApcrel (= single ADR) instruction to generate a
global address on any ARM target I know of. Fortunately, no-one was trying to
any more, but there were vestigial patterns.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195644 91177308-0d34-0410-b5e6-96231b3b80d8
Make helper function static.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195650 91177308-0d34-0410-b5e6-96231b3b80d8