Improve GenConstString, GenS{get,put} for x86

Rewrite GenConstString for x86 to skip calling ResolveString when the
string is already resolved.  Also try to avoid a register copy if the
Method* is in a promoted register.

Implement the TODO for GenS{get,put} to use compare to memory for x86 by
adding a new codegen function to compare directly to memory.  Implement
a default implementation that uses a temporary register for RISC
architectures.

Change-Id: Ie163cca3d3d841aa10c50dc6592ec30af7a7cbc9
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>
5 files changed