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

llvm-svn: 86235

from various APIs, addressing PR5325.

llvm-svn: 86231

llvm-svn: 86193

llvm-svn: 86180

LoopSimplify form may not be available.

llvm-svn: 86175

LoopPassManager for it.

llvm-svn: 86163

llvm-svn: 86141

llvm-svn: 86133

Hans Wennborg!

llvm-svn: 86067

resizes in IPSCCP.  This fixes PR5394.

llvm-svn: 86036

to EmitGEPOffset.  

Implement some new transforms for optimizing 
subtracts of two pointer to ints into the same vector.  This happens
for C++ iterator idioms for example, stringmap takes a const char*
that points to the start and end of a string.  Once inlined, we want
the pointer difference to turn back into a length.

This is rdar://7362831.

llvm-svn: 86021

more aggressive an correct.  This survives building llvm in 64-bit
mode with optimizations and the built llvm passes make check.

llvm-svn: 85973

llvm-svn: 85937

functions that don't have local linkage.  Basically, we need to be more
careful about propagating argument information to functions whose results
we aren't tracking.  This fixes a miscompilation of 
LLVMCConfigurationEmitter.cpp when built with an llvm-gcc that has ipsccp
enabled.

llvm-svn: 85923

to follow.

llvm-svn: 85903

llvm-svn: 85858

std::map to DenseMap, exposed on release llvm-gcc bootstrap.

llvm-svn: 85840

llvm-svn: 85818

disable it until I can fix it.

llvm-svn: 85810

function to calls of that function, regardless of whether it has local
linkage or has its address taken.  Not escaping should only affect 
whether we make an aggressive assumption about the arguments to a 
function, not whether we can track the result of it.

llvm-svn: 85795

llvm-svn: 85793

a shared place instead of duplicating it 4 times.

llvm-svn: 85792

"multiple return values" but not "first class aggregates"

llvm-svn: 85791

llvm-svn: 85790

instead of reinventing SCCP-specific logic.  This gives us
new powers.

llvm-svn: 85789

a DenseMap.  Doing this required being aware of subtle iterator
invalidation issues, but it provides a big speedup.  In a 
release-asserts build, this sped up optimizing 403.gcc from
1.34s -> 0.79s (IPSCCP) and 1.11s -> 0.44s (SCCP).

This commit also conflates in a bunch of general cleanups, sorry.

llvm-svn: 85788

an assertion on the buildbot.

llvm-svn: 85784

simplify some code.

llvm-svn: 85783

llvm-svn: 85780

llvm-svn: 85778

llvm-svn: 85777

function, eliminate temporary (and pointless) smallvector.

llvm-svn: 85776

llvm-svn: 85775

llvm-svn: 85774

llvm-svn: 85773

of the two loads agree.  Propagate that onto the new store.

llvm-svn: 85772

not the max.  This didn't matter until the previous patch because
instcombine would refuse to sink loads with differenting alignments.

llvm-svn: 85738

llvm-svn: 85737

phis, it didn't preserve the alignment of the load.  This is a missed
optimization of the alignment is high and a miscompilation when the
alignment is low.

llvm-svn: 85736