[MachineInstr] In addRegisterKilled and addRegisterDead, don't remove operands...

[MachineInstr] In addRegisterKilled and addRegisterDead, don't remove operands from inline assembly instructions if they have an associated flag operand.

INLINEASM instructions use extra operands to carry flags. If a register operand is removed without removing the flag operand, then the flags will no longer make sense.

This patch fixes this by preventing the removal when a flag operand is present.

The included test case was generated by MS inline assembly. Longer term maybe we should fix the inline assembly parsing to not generate redundant operands.

Differential Revision: https://reviews.llvm.org/D51829

llvm-svn: 342176