ARM cost model: Cost for scalar integer casts and floating point conversions

Also adds some costs for vector integer float conversions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174371 91177308-0d34-0410-b5e6-96231b3b80d8
Link .ARM.exidx with corresponding text section.

The sh_link in the ELF section header of .ARM.exidx should
be filled with the section index of the corresponding text
section.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174372 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r174343, "When the target-independent DAGCombiner inferred a higher alignment for a load,"

It caused hangups in compiling clang/lib/Parse/ParseDecl.cpp and clang/lib/Driver/Tools.cpp in stage2 on some hosts.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174374 91177308-0d34-0410-b5e6-96231b3b80d8