This function does more or less the same as
MI::readsWritesVirtualRegister(), but it supports bundles as well.

It also determines if any constraint requires reading and writing
operands to use the same register.  Most clients want to know.

Use the more modern MO.readsReg() instead of trying to sort out undefs
and partial redefines.  Stop supporting the extra full <imp-def> operand
as an alternative to <def,undef> sub-register defines.

llvm-svn: 151690

Moving toward a uniform style of pass definition to allow easier target configuration.
Globally declare Pass ID.
Globally declare pass initializer.
Use INITIALIZE_PASS consistently.
Add a call to the initializer from CodeGen.cpp.
Remove redundant "createPass" functions and "getPassName" methods.

While cleaning up declarations, cleaned up comments (sorry for large diff).

llvm-svn: 150100

llvm-svn: 148465

llvm-svn: 148462

  to instruction right after the last instruction in the bundle.
- Add a finalizeBundle() variant that doesn't specify LastMI. Instead, the code
  will find the last instruction in the bundle by following the 'InsideBundle'
  marker. This is useful in case bundles are formed early (i.e. during MI
  scheduling) but finalized later (i.e. after register allocator has finished
  rewriting virtual registers with physical registers).

llvm-svn: 148444

llvm-svn: 148440

  to finalize MI bundles (i.e. add BUNDLE instruction and computing register def
  and use lists of the BUNDLE instruction) and a pass to unpack bundles.
- Teach more of MachineBasic and MachineInstr methods to be bundle aware.
- Switch Thumb2 IT block to MI bundles and delete the hazard recognizer hack to
  prevent IT blocks from being broken apart.

llvm-svn: 146542