[AMDGPU] Add GCNHazardRecognizer::checkInlineAsmHazards() and...

[AMDGPU] Add GCNHazardRecognizer::checkInlineAsmHazards() and GCNHazardRecognizer::checkVALUHazardsHelper(). checkInlineAsmHazards() checks INLINEASM for hazards that we particularly care about (so not exhaustive); this patch adds a check for INLINEASM that defs vregs that hold data-to-be stored by immediately preceding store of more than 8 bytes. If the instr were not within an INLINEASM, this scenario would be handled by checkVALUHazard(). Add checkVALUHazardsHelper(), which will be called by both checkVALUHazards() and checkInlineAsmHazards().

Differential Revision: https://reviews.llvm.org/D40098

llvm-svn: 320083