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

need TargetData, just return false if we don't have it.

Update testcases accordingly.

Fixes PR6807.

llvm-svn: 101011

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

parameters in the CBE by implicitly adding a fixed argument.
This allows eliminating a work-around from DAE.  Patch by
Sylvere Teissier!

llvm-svn: 100944

in some cases.

llvm-svn: 100937

llvm-svn: 100936

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

variable TARGET_HAS_DYNAMIC_LIBS

llvm-svn: 100896

llvm-svn: 100895

llvm-svn: 100893

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

llvm-svn: 100883

llvm-svn: 100862

llvm-svn: 100859

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

ensure that the expansion is dominated by the increments of those loops.

llvm-svn: 100748

llvm-svn: 100720

llvm-svn: 100710

llvm-svn: 100709

explicitly split into stride-and-offset pairs. Also, add the
ability to track multiple post-increment loops on the same expression.

This refines the concept of "normalizing" SCEV expressions used for
to post-increment uses, and introduces a dedicated utility routine for
normalizing and denormalizing expressions.

This fixes the expansion of expressions which are post-increment users
of more than one loop at a time. More broadly, this takes LSR another
step closer to being able to reason about more than one loop at a time.

llvm-svn: 100699

llvm-svn: 100677

llvm-svn: 100550

llvm-svn: 100549

llvm-svn: 100547

llvm-svn: 100546

and remove assumptions about operand order

llvm-svn: 100544

undefs in branches/switches, we have two cases: a branch on a literal
undef or a branch on a symbolic value which is undef.  If we have a
literal undef, the code was correct: forcing it to a constant is the
right thing to do.

If we have a branch on a symbolic value that is undef, we should force
the symbolic value to a constant, which then makes the successor block
live.  Forcing the condition of the branch to being a constant isn't 
safe if later paths become live and the value becomes overdefined.  This
is the case that 'forcedconstant' is designed to handle, so just use it.

This fixes rdar://7765019 but there is no good testcase for this, the
one I have is too insane to be useful in the future.

llvm-svn: 100478

llvm-svn: 100468

llvm-svn: 100467

Added support for address spaces and added a isVolatile field to memcpy, memmove, and memset,
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)

llvm-svn: 100304

exits the loop.  With this information we can guarantee 
the iteration count of the loop is bounded by the 
compare.  I think this xforms is finally safe now.

llvm-svn: 100285

checker.  Amusingly, we already had tests that we should
have rejects because they would be miscompiled in the
testsuite.

The remaining issue with this is that we don't check that
the branch causes us to exit the loop if it fails, so we
don't actually know if we remain in bounds.

llvm-svn: 100284