memory operands that have a direct operand should have their stores created

before the copies into physregs are done.  This avoids having flag operands
skip the store, causing cycles in the dag at sched time.  This fixes infinite
loops on these tests:

test/CodeGen/Generic/2007-04-08-MultipleFrameIndices.ll for PR1308
test/CodeGen/PowerPC/2007-01-29-lbrx-asm.ll
test/CodeGen/PowerPC/2007-01-31-InlineAsmAddrMode.ll
test/CodeGen/X86/2006-07-12-InlineAsmQConstraint.ll for PR828

llvm-svn: 36547