simplifies instruction users of PHIs when the phi is eliminated.  This
will be moved to transforms/utils after some other refactoring.

llvm-svn: 86603

llvm-svn: 86497

(making pred factoring only happen if threading is guaranteed
to be successful).

This now survives an X86-64 bootstrap of llvm-gcc.

llvm-svn: 86355

86289, 86278, 86270, 86267, 86266 & 86264
Chris, please take a look.

llvm-svn: 86321

llvm-svn: 86314

set only once even if it has multiple edges to BB.

llvm-svn: 86299

llvm-svn: 86289

llvm-svn: 86278

llvm-svn: 86270

llvm-svn: 86267

llvm-svn: 86266

predicates.  This allows us to jump thread things like:

_ZN12StringSwitchI5ColorE4CaseILj7EEERS1_RAT__KcRKS0_.exit119:
  %tmp1.i24166 = phi i8 [ 1, %bb5.i117 ], [ %tmp1.i24165, %_Z....exit ], [ %tmp1.i24165, %bb4.i114 ] 
  %toBoolnot.i87 = icmp eq i8 %tmp1.i24166, 0     ; <i1> [#uses=1]
  %tmp4.i90 = icmp eq i32 %tmp2.i, 6              ; <i1> [#uses=1]
  %or.cond173 = and i1 %toBoolnot.i87, %tmp4.i90  ; <i1> [#uses=1]
  br i1 %or.cond173, label %bb4.i96, label %_ZN12...

Where it is "obvious" that when coming from %bb5.i117 that the 'and' is always 
false.  This triggers a surprisingly high number of times in the testsuite, 
and gets us closer to generating good code for doug's strswitch testcase.

This also make a bunch of other code in jump threading redundant, I'll rip
out in the next patch.  This survived an enable-checking llvm-gcc bootstrap.

llvm-svn: 86264

from various APIs, addressing PR5325.

llvm-svn: 86231

Hans Wennborg!

llvm-svn: 86067

now-probably-dead instruction tree feeding it.

llvm-svn: 83778

done by condprop, but do it in a much more general form.  The
basic idea is that we can do a limited form of tail duplication
in the case when we have a branch on a phi.  Moving the branch
up in to the predecessor block makes instruction selection
much easier and encourages chained jump threadings.

llvm-svn: 83759

llvm-svn: 83756

llvm-svn: 83755

llvm-svn: 83754

DemoteRegToStack.  This makes it more efficient (because it isn't
creating a ton of load/stores that are eventually removed by a later
mem2reg), and more slightly more effective (because those load/stores
don't get in the way of threading).

llvm-svn: 83706

update all the callers.

llvm-svn: 82889

llvm-svn: 80766

llvm-svn: 78948

llvm-svn: 77685

llvm-svn: 77635

llvm-svn: 77494

llvm-svn: 77152

llvm-svn: 77145

Revert the ConstantInt constructors back to their 2.5 forms where possible, thanks to contexts-on-types.  More to come.

llvm-svn: 77011

instead of getAnalysis<TargetData>().

llvm-svn: 76982

llvm-svn: 76702

llvm-svn: 76598

llvm-svn: 75863

llvm-svn: 75703

This started as a small change, I swear.  Unfortunately, lots of things call the [I|F]CmpInst constructors.  Who knew!?

llvm-svn: 75200

llvm-svn: 74878

llvm-svn: 74844

llvm-svn: 74753

This was considering vector intrinsics to have cost 2, but non-vector
intrinsics to have cost 1, which is backward.

llvm-svn: 74698

a key is present in a std::map or DenseMap to use find instead.

llvm-svn: 74676