loop unswitch, and use inst simplify instead.  It is more
powerful and less duplication.

llvm-svn: 101874

condition we're unswitching on.  In this case, don't try to
simplify the second copy of the loop which may be dead or not,
but is probably a constant now.  This fixes PR6879

llvm-svn: 101870

just ask ScalarEvolution for it on demand. This helps IVUsers be more robust
in the case of expressions changing underneath it. This fixes PR6862.

llvm-svn: 101819

Probably the best way to know that all getOperand() calls have been handled
is to replace that API instead of updating.

llvm-svn: 101579

callee is expected to be expanded to something else by codegen, so that
normal infinitely recursive calls are still transformed.

llvm-svn: 101468

with a fix for self-hosting

rotate CallInst operands, i.e. move callee to the back
of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101465

llvm-svn: 101437

llvm-svn: 101434

wanted the alignment of the pointee.

llvm-svn: 101432

llvm-svn: 101429

place.

llvm-svn: 101427

ConvertToScalarInfo.

llvm-svn: 101425

llvm-svn: 101423

CanConvertToScalar/MergeInType.  Eliminate a pointless
LLVMContext argument to MergeInType.

llvm-svn: 101422

llvm-svn: 101405

with a fix

rotate CallInst operands, i.e. move callee to the back
of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101397

llvm-svn: 101376

llvm-svn: 101368

of the operand array

the motivation for this patch are laid out in my mail to llvm-commits:
more efficient access to operands and callee, faster callgraph-construction,
smaller compiler binary

llvm-svn: 101364

llvm-svn: 101253

llvm-svn: 101250

llvm-svn: 101125

llvm-svn: 101117

numerator is an induction variable. For example, with code like this:

  for (i=0;i<n;++i)
    x[i%n] = 0;

IndVarSimplify will now recognize that i is always less than n inside
the loop, and eliminate the remainder.

llvm-svn: 101113

expression is a UDiv and it doesn't appear that the UDiv came from
the user's source.

ScalarEvolution has recently figured out how to compute a tripcount
expression for the inner loop in
SingleSource/Benchmarks/Shootout/sieve.c, using a udiv. Emitting a
udiv instruction dramatically slows down the enclosing loop.

llvm-svn: 101068

llvm-svn: 101033

a ScalarEvolution bug with overflow handling is fixed, the normal analysis
code will automatically decline to operate on the icmp instructions which
are responsible for the loop exit.

llvm-svn: 101032

instead of deleting just the user. This makes it more consistent with
other code in IndVarSimplify, and theoretically can eliminate more users
earlier.

llvm-svn: 101027

the loop exit test. This usually doesn't come up for a variety of
reasons, but it isn't impossible, so make IndVarSimplify handle it
conservatively.

llvm-svn: 101008

llvm-svn: 101002

variables. For example, with code like this:

  for (i=0;i<n;++i)
    if (i<n)
      x[i] = 0;

IndVarSimplify will now recognize that i is always less than n inside
the loop, and eliminate the if.

llvm-svn: 101000

that it's only testing for the entry condition, not full loop-invariant
conditions.

llvm-svn: 100979

in some cases.

llvm-svn: 100937

into adjacent loops. Also, ensure that the insert position is
dominated by the loop latch of any loop in the post-inc set which
has a latch.

llvm-svn: 100906

so that an unfortunately placed bitcast doesn't pin a value in a
register.

llvm-svn: 100883

llvm-svn: 100856

a separate function.

llvm-svn: 100845

forced constant is changed to a constant, we would end
up adding the instruction to the wrong worklist, 
preventing it from being properly revisited.  This fixes
rdar://7832370

llvm-svn: 100837

inputs happen to negate each other.

llvm-svn: 100828

llvm-svn: 100824