should make subsequent changes simpler.  This also allows us to hoist vaarg
and vanext instructions

llvm-svn: 10342

Code cleanups
Make LICM::SafeToHoist marginally more efficient

llvm-svn: 10341

llvm-svn: 10339

llvm-svn: 10338

llvm-svn: 10337

This is here to remind me to get back to this after a while.

llvm-svn: 10336

llvm-svn: 10335

llvm-svn: 10334

Also make sure to clean up any PHI nodes that are inserted which are pointless.

llvm-svn: 10333

We now insert accumulator variables as necessary to eliminate tail recursion
more aggressively.  This is still fairly limited, but allows us to transform
fib/factorial, and other functions into nice happy loops.  :)

llvm-svn: 10332

tail recursion

llvm-svn: 10331

llvm-svn: 10325

llvm-svn: 10324

llvm-svn: 10323

llvm-svn: 10322

llvm-svn: 10321

llvm-svn: 10320

  The first returns a function pointer or a stub if it's not already generated
  The second exposes what was previously JIT specific state to general clients

llvm-svn: 10319

llvm-svn: 10318

llvm-svn: 10317

llvm-svn: 10316

llvm-svn: 10315

llvm-svn: 10314

llvm-svn: 10313

The only functionality change is that we now implement:
  Regression/Transforms/TailCallElim/intervening-inst.ll

Which is really kinda pointless, because it means that trivially dead code
does not interfere with -tce, but trivially dead code probably wouldn't be
around anytime when this pass is run anyway.

The point of including this change it to support other more aggressive
transformations when we have the analysis capabilities to do so.

llvm-svn: 10312

llvm-svn: 10311

can write to memory.

llvm-svn: 10310

llvm-svn: 10309

llvm-svn: 10308

llvm-svn: 10307

llvm-svn: 10306

llvm-svn: 10305

llvm-svn: 10304

* Transform: free <ty>* (cast <ty2>* X to <ty>*) into free <ty2>* X

llvm-svn: 10303

which never worked itself.  The cee pass still doesn't work, but it doesn't use
this method anymore anyway, so eliminate the method.

llvm-svn: 10302

on the algorithm for directly computing immediate dominators presented in this
paper:

  A Fast Algorithm for Finding Dominators in a Flowgraph
  T. Lengauer & R. Tarjan, ACM TOPLAS July 1979, pgs 121-141.

This _substantially_ speeds up construction of all dominator related information.
Post-dominators to follow.

llvm-svn: 10301

instead of the other way around.

llvm-svn: 10300

Move method out of generic dominators construction code

llvm-svn: 10299

llvm-svn: 10298

New command line parsing. This isn't as perfect as I would have liked. The CommandLine Library needs to be extended, in order to parse the options and allow for optional dashes. In addition, the help option isn't correct since I do the parsing mostly myself. But this is in the ocorrect ar format.

llvm-svn: 10297