take multiple cycles to decode.
For the current if-converter clients (actually only ARM), the instructions that
are predicated on false are not nops. They would still take machine cycles to
decode. Micro-coded instructions such as LDM / STM can potentially take multiple
cycles to decode. If-converter should take treat them as non-micro-coded
simple instructions.

llvm-svn: 113570

llvm-svn: 110460

llvm-svn: 110410

ID member as the sole unique type identifier.  Clean up APIs related to this change.

llvm-svn: 110396

llvm-svn: 108450

- This fixed a number of bugs in if-converter, tail merging, and post-allocation
  scheduler. If-converter now runs branch folding / tail merging first to
  maximize if-conversion opportunities.
- Also changed the t2IT instruction slightly. It now defines the ITSTATE
  register which is read by instructions in the IT block.
- Added Thumb2 specific hazard recognizer to ensure the scheduler doesn't
  change the instruction ordering in the IT block (since IT mask has been
  finalized). It also ensures no other instructions can be scheduled between
  instructions in the IT block.

This is not yet enabled.

llvm-svn: 106344

- Rename ExactHazardRecognizer to PostRAHazardRecognizer and move its header to include to allow targets to extend it.

llvm-svn: 105959

llvm-svn: 105862

that are aliases of the specified register.
- Rename modifiesRegister to definesRegister since it's looking a def of the
specific register or one of its super-registers. It's not looking for def of a
sub-register or alias that could change the specified register.
- Added modifiesRegister to look for defs of aliases.

llvm-svn: 104377

llvm-svn: 104254

llvm-svn: 104175

llvm-svn: 103806

while debugging what's mishandled about them in the post-RA pass.

llvm-svn: 103805

changes before doing phi lowering for switches.

llvm-svn: 102809

just remove them all.  Radar 7873207 (working around the root problem of
Radar 7759363).

llvm-svn: 101604

llvm-svn: 101043

llvm-svn: 97765

llvm-svn: 92594

llvm-svn: 90970

The MO reference to a MachineOperand can be invalidated by
MachineInstr::addOperand. Don't even use it for debugging.

llvm-svn: 90381

Remove some old experimental code that is no longer needed. Remove additional, speculative scheduling pass as its cost did not translate into significant performance improvement. Minor tweaks.

llvm-svn: 89471

llvm-svn: 88682

llvm-svn: 87015

llvm-svn: 86634

Allow targets to specify register classes whose member registers should not be renamed to break anti-dependencies. 

llvm-svn: 86628

Break anti-dependencies using free registers in a round-robin manner to avoid introducing new anti-dependencies.

llvm-svn: 86098

Do a scheduling pass ignoring anti-dependencies to identify candidate registers that should be renamed.

llvm-svn: 85939

 - Be consistent when referring to MachineBasicBlocks: BB#0.
 - Be consistent when referring to virtual registers: %reg1024.
 - Be consistent when referring to unknown physical registers: %physreg10.
 - Be consistent when referring to known physical registers: %RAX
 - Be consistent when referring to register 0: %reg0
 - Be consistent when printing alignments: align=16
 - Print jump table contents.
 - Don't print host addresses, in general.
 - and various other cleanups.

llvm-svn: 85682

llvm-svn: 85412

Allow the aggressive anti-dep breaker to process the same region multiple times. This is necessary because new anti-dependencies are exposed when "current" ones are broken.

llvm-svn: 85166

llvm-svn: 85146

Add aggressive anti-dependence breaker. Currently it is not the default for any target. Enable with -break-anti-dependencies=all.

llvm-svn: 85145

llvm-svn: 85127

VISIBILITY_HIDDEN removal.

llvm-svn: 85043

Chris claims we should never have visibility_hidden inside any .cpp file but
that's still not true even after this commit.

llvm-svn: 85042

Allow the target to select the level of anti-dependence breaking that should be performed by the post-RA scheduler. The default is none.

llvm-svn: 84911

llvm-svn: 84727

Respect src register allocation requirements when breaking anti-dependencies. Remove some dead code.

llvm-svn: 84691

llvm-svn: 84658

llvm-svn: 84273