Allow the aggressive anti-dep breaker to process the same region multiple times. This is necessary because new anti-dependencies are exposed when "current" ones are broken.

llvm-svn: 85166

the loop exiting block dominates the latch block; if ScalarEvolution
can prove that the trip-count is finite, that's sufficient.

llvm-svn: 85165

can safely use the NSW bit on the Add.

llvm-svn: 85164

llvm-svn: 85161

aggressive on PHI instructions.

llvm-svn: 85158

llvm-svn: 85149

llvm-svn: 85148

-Wno-missing-field-initializers or -Wno-variadic-macros.

llvm-svn: 85147

llvm-svn: 85146

Add aggressive anti-dependence breaker. Currently it is not the default for any target. Enable with -break-anti-dependencies=all.

llvm-svn: 85145

GEPs (more than one non-zero index) into simple GEPs (at most one
non-zero index).  In some simple experiments using this it's not
uncommon to see 3% overall code size wins, because it exposes
redundancies that can be eliminated, however it's tricky to use
because instcombine aggressively undoes the work that this pass does.

llvm-svn: 85144

llvm-svn: 85141

llvm-svn: 85138

for consistency with ConstantFolder.

llvm-svn: 85137

machineinstr whether the aliased register is dead, rather than the original
register is dead. This allows it to get the correct answer when examining
an instruction like this:
  CALLpcrel32 <ga:foo>, %AL<imp-def>, %EAX<imp-def,dead>
where EAX is dead but a subregister of it is still live. This fixes PR5294.

llvm-svn: 85135

llvm-svn: 85134

llvm-svn: 85130

llvm-svn: 85127

Patch by Talin!

llvm-svn: 85126

llvm-svn: 85120

All of the 'demorgan' related xforms need to use 
dyn_castNotVal, not m_Not.

llvm-svn: 85119

strides for now, because it doesn't handle them correctly. This fixes a
miscompile of SingleSource/Benchmarks/Misc-C++/ray.

This problem was usually hidden because indvars transforms such induction
variables into negations of canonical induction variables.

llvm-svn: 85118

  bootstrapping. It's not safe to leave identity subreg_to_reg and insert_subreg
  around.
- Relax register scavenging to allow use of partially "not-live" registers. It's
  common for targets to operate on registers where the top bits are undef. e.g.
  s0 =
  d0 = insert_subreg d0<undef>, s0, 1
  ...
     = d0
  When the insert_subreg is eliminated by the coalescer, the scavenger used to
  complain. The previous fix was to keep to insert_subreg around. But that's
  brittle and it's overly conservative when we want to use the scavenger to 
  allocate registers. It's actually legal and desirable for other instructions
  to use the "undef" part of d0. e.g.
  s0 =
  d0 = insert_subreg d0<undef>, s0, 1
  ...
  s1 =
     = s1
     = d0
  We probably need add a "partial-undef" marker on machine operand so the
  machine verifier would not complain.

llvm-svn: 85091

llvm-svn: 85090

llvm-svn: 85088

direct inclusion edge from System to Support.

llvm-svn: 85086

   not (or (icmp, icmp)) -> and(icmp, icmp)

llvm-svn: 85085

llvm-svn: 85083

llvm-svn: 85082

or global after a function with conflicting names.  Update some testcases
that were accidentally depending on this behavior.

llvm-svn: 85081

llvm-svn: 85078

functions it should just look them up like declarations.

llvm-svn: 85077

llvm-svn: 85074

llvm-svn: 85065

llvm-svn: 85064

llvm-svn: 85052

llvm-svn: 85051

llvm-svn: 85050

llvm-svn: 85049

llvm-svn: 85048