Natural Loop Information
 Loop Pass Manager
   Canonicalize natural loops
 Scalar Evolution Analysis
 Loop Pass Manager
   Induction Variable Users
   Canonicalize natural loops
   Induction Variable Users
   Loop Strength Reduction

into this:

Scalar Evolution Analysis
Loop Pass Manager
  Canonicalize natural loops
  Induction Variable Users
  Loop Strength Reduction

This fixes <rdar://problem/8869639>. I also filed PR9184 on doing this sort of
thing automatically, but it seems easier to just change the ordering of the
passes if this is the only case.

llvm-svn: 125254

improve interfaces to instsimplify to take this info.

llvm-svn: 125196

versions of creation functions.  Eventually, the "insertion point" versions
of these should just be removed, we do have IRBuilder afterall.

Do a massive rewrite of much of pattern match.  It is now shorter and less
redundant and has several other widgets I will be using in other patches.
Among other changes, m_Div is renamed to m_IDiv (since it only matches 
integer divides) and m_Shift is gone (it used to match all binops!!) and
we now have m_LogicalShift for the one client to use.

Enhance IRBuilder to have "isExact" arguments to things like CreateUDiv
and reduce redundancy within IRbuilder by having these methods chain to
each other more instead of duplicating code.

llvm-svn: 125194

could end up removing a different function than we intended because it was
functionally equivalent, then end up with a comparison of a function against
itself in the next round of comparisons (the one in the function set and the
one on the deferred list). To fix this, I introduce a choice in the form of
comparison for ComparableFunctions, either normal or "pointer only" used to
find exact Function*'s in lookups.

Also add some debugging statements.

llvm-svn: 125180

the active loop. This is generally desirable, and it avoids trouble
in situations such as the testcase in PR9123, though the failure
mode depends on use-list order, so it is infeasible to test.

llvm-svn: 125065

SimplifyCFG: Track the number of used icmps when turning a icmp chain into a switch. If we used only one icmp, don't turn it into a switch.

Also prevent the switch-to-icmp transform from creating identity adds, noticed by Marius Wachtler.

llvm-svn: 125056

instcombine xform to exercise this.

Nothing forms exact udivs yet though.  This is progress on PR8862

llvm-svn: 124992

llvm-svn: 124977

now, and this wasn't comparing some of their relevant bits anyhow.

llvm-svn: 124976

SimplifyCFG: Also transform switches that represent a range comparison but are not sorted into sub+icmp.

This transforms another 1000 switches in gcc.c.

llvm-svn: 124826

This makes the job of the later optzn passes easier, allowing the vast amount of
icmp transforms to chew on it.

We transform 840 switches in gcc.c, leading to a 16k byte shrink of the resulting
binary on i386-linux.

The testcase from README.txt now compiles into
  decl  %edi
  cmpl  $3, %edi
  sbbl  %eax, %eax
  andl  $1, %eax
  ret

llvm-svn: 124724

that might have changed been affected by a merge elsewhere will have been
removed from the function set, and it isn't needed for performance because we
call grow() ahead of time to prevent reallocations.

llvm-svn: 124717

reassociation. No testcase, because I wasn't able to create a testcase
which actually demonstrates a problem.

llvm-svn: 124713

llvm-svn: 124712

(A+B) == A  ->  B == 0
A == (A+B)  ->  B == 0

llvm-svn: 124567

The DEBUG() call at line 606 demands to see raw_ostream's definition. I have no idea why this seems to only break MSVC.

llvm-svn: 124545

llvm-svn: 124535

llvm-svn: 124534

llvm-svn: 124527

llvm-svn: 124526

llvm-svn: 124522

Re-commit r124462 with fixes. Tail recursion elim will now dup ret into unconditional predecessor to enable TCE on demand.

llvm-svn: 124518

Modified patch by Adam Preuss.

This builds on the existing framework for block tracing, edge profiling and optimal edge profiling.
See -help-hidden for new flags.
For documentation, see the technical report "Implementation of Path Profiling..." in llvm.org/pubs.

llvm-svn: 124515

benchmarks, and that it can be simplified to X/Y.  (In general you can only
simplify (Z*Y)/Y to Z if the multiplication did not overflow; if Z has the
form "X/Y" then this is the case).  This patch implements that transform and
moves some Div logic out of instcombine and into InstructionSimplify.
Unfortunately instcombine gets in the way somewhat, since it likes to change
(X/Y)*Y into X-(X rem Y), so I had to teach instcombine about this too.
Finally, thanks to the NSW/NUW flags, sometimes we know directly that "Z*Y"
does not overflow, because the flag says so, so I added that logic too.  This
eliminates a bunch of divisions and subtractions in 447.dealII, and has good
effects on some other benchmarks too.  It seems to have quite an effect on
tramp3d-v4 but it's hard to say if it's good or bad because inlining decisions
changed, resulting in massive changes all over.

llvm-svn: 124487

functionality change.

llvm-svn: 124482

llvm-svn: 124480

llvm-svn: 124479

llvm-svn: 124478

the function equality set.

llvm-svn: 124475

llvm-svn: 124469

  branches. PR8575, rdar://5134905, rdar://8911460.
- Allow codegen tail duplication to dup small return blocks after register
  allocation is done.

llvm-svn: 124462

llvm-svn: 124426

llvm-svn: 124406

llvm-svn: 124404

that relationships like "i8* null" is equivalent to "i32* null".

llvm-svn: 124368

operand being factorized (and erased) could occur several times in Ops,
resulting in freed memory being used when the next occurrence in Ops was
analyzed.

llvm-svn: 124287

it. No functionality change!

llvm-svn: 124286

merge vector<intptr_t>::push_back() and vector<void*>::push_back() because
Enumerate() doesn't realize that "i64* null" and "i8** null" are equivalent.

llvm-svn: 124285

elements for type equivalence.

llvm-svn: 124284

for now. It's controlled by the HasGlobalAliases variable which is not attached
to any flag yet.

llvm-svn: 124182