Fix rdtsc.ll test to match r8 on win64

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207142 91177308-0d34-0410-b5e6-96231b3b80d8
Add 'musttail' marker to call instructions

This is similar to the 'tail' marker, except that it guarantees that
tail call optimization will occur.  It also comes with convervative IR
verification rules that ensure that tail call optimization is possible.

Reviewers: nicholas

Differential Revision: http://llvm-reviews.chandlerc.com/D3240

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207143 91177308-0d34-0410-b5e6-96231b3b80d8
Remove dead inline function that doesn't compile

MSVC doesn't diagnose this, interestingly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207144 91177308-0d34-0410-b5e6-96231b3b80d8
X86: Don't transform shifts into ands when the sign bit is tested.

Should unbreak MultiSource/Benchmarks/mediabench/g721/g721encode/encode.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207145 91177308-0d34-0410-b5e6-96231b3b80d8