SDISel's constant branch folding can fold away self-loops, which doesn't result in any dead blocks, but
rather an incorrect phi input.  Add code to UnreachableMachineBlockElim to get rid of these entries.

llvm-svn: 54432

llvm-svn: 54378

llvm-svn: 54374

llvm-svn: 54337

- Add a basic machine-level dead block eliminator.

These two have to go together, since many other parts of the code generator are unable to handle the unreachable blocks otherwise created.

llvm-svn: 54333

several things that were neither in an anonymous namespace nor static
but not intended to be global.

llvm-svn: 51017

llvm-svn: 45418

llvm-svn: 36873

llvm-svn: 36662

Due to darwin gcc bug, one version of darwin linker coalesces
static const int, which defauts PassID based pass identification.

llvm-svn: 36652

llvm-svn: 36632

llvm-svn: 29925

llvm-svn: 29911

dropped.  This shrinks libllvmgcc.dylib another 67K

llvm-svn: 28975

llvm-svn: 21420

Bill Wendling!!

llvm-svn: 20649

Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.

llvm-svn: 16137

http://llvm.cs.uiuc.edu/PR403 .

llvm-svn: 15333

basic block clear()'s all of the operands lists, including phis.  This
caused removePredecessor to get confused later.  Because of this, we just
nuke (without prejudice) PHI nodes in unreachable blocks.

llvm-svn: 14635

pass is required to paper over problems in the code generator (primarily
live variables and its clients) which doesn't really have any well defined
semantics for unreachable code.

The proper solution to this problem is to have instruction selectors not
select blocks that are unreachable.  Until we have a instruction selection
framework available for use, however, we can't expect all instruction
selector writers to do this.  Until then, this pass should be used.

llvm-svn: 14563