ThreadEdge directly.  This shares the code, but is just a refactoring.
* Make JumpThreading compute the set of loop headers and avoid threading
  across them.  This prevents jump threading from forming irreducible 
  loops (goodness) but also prevents it from threading in other cases that
  are beneficial (see the comment above FindFunctionBackedges).

llvm-svn: 70820

FindFunctionBackedges function.

llvm-svn: 70819

llvm-svn: 70817

The stack slots which share the same stack slot after coloring can, but do not have to, use the same register. In fact, they each may have different register class requirements.

llvm-svn: 70815

llvm-svn: 70811

llvm-svn: 70804

-Depend on DebugLocs for source line info.

llvm-svn: 70803

llvm-svn: 70792

is the empty set. :)  Thanks to Fritz for pointing this out.

llvm-svn: 70790

throw exceptions.

llvm-svn: 70788

In some rare cases, the register allocator can spill registers but end up not utilizing registers at all. The fundamental problem is linearscan's backtracking can end up freeing more than one allocated registers. However,  reloads and restores might be folded into uses / defs and freed registers might not be used at all.

VirtRegMap keeps track of allocations so it knows what's not used. As a horrible hack, the stack coloring can color spill slots with *free* registers. That is, it replace reload and spills with copies from and to the free register. It unfold instructions that load and store the spill slot and replace them with register using variants.

Not yet enabled. This is part 1. More coming.

llvm-svn: 70787

Thanks for Dan Gohman for suggestion!

llvm-svn: 70782

llvm-svn: 70772

llvm-svn: 70770

llvm-svn: 70769

llvm-svn: 70768

llvm-svn: 70767

Temporary disable imm patterns for cmp. Actually, all cmp-related stuff (select_cc, setcc, br_cc). needs to be rethought

llvm-svn: 70766

llvm-svn: 70765

llvm-svn: 70764

llvm-svn: 70763

llvm-svn: 70762

llvm-svn: 70761

llvm-svn: 70760

llvm-svn: 70759

llvm-svn: 70758

llvm-svn: 70757

llvm-svn: 70755

llvm-svn: 70754

llvm-svn: 70753

llvm-svn: 70752

llvm-svn: 70751

llvm-svn: 70750

llvm-svn: 70749

llvm-svn: 70748

llvm-svn: 70747

llvm-svn: 70746

It's error-prone to maintain two separate variants of asmprinting stuff, one of which is even used. Drop second (aka 'intel') variant of operands. It can be added later, if needed.

llvm-svn: 70745

llvm-svn: 70744

llvm-svn: 70743