argument of createGVNPass and set it automatically for -O3.

llvm-svn: 97245

llvm-svn: 97235

llvm-svn: 97036

the DominatorTree. ...", in hopes of restoring poor old PPC bootstrap.

llvm-svn: 97027

argument is non-null, pass it along to PHITranslateSubExpr so that it can
prefer using existing values that dominate the PredBB, instead of just
blindly picking the first equivalent value that it finds on a uselist.
Also when the DominatorTree is specified, have PHITranslateValue filter
out any result that does not dominate the PredBB.  This is basically just
refactoring the check that used to be in GetAvailablePHITranslatedSubExpr
and also in GVN.

Despite my initial expectations, this change does not affect the results
of GVN for any testcases that I could find, but it should help compile time.
Before this change, if PHITranslateSubExpr picked a value that does not
dominate, PHITranslateWithInsertion would then insert a new value, which GVN
would later determine to be redundant and would replace.  By picking a good
value to begin with, we save GVN the extra work of inserting and then
replacing a new value.

llvm-svn: 97010

I don't have a small testcase for this.

llvm-svn: 96890

failures from ValueTable::verifyRemoved() when using -debug.

llvm-svn: 96805

llvm-svn: 96387

llvm-svn: 96378

terminator's list of successors.

llvm-svn: 96377

and T->isPointerTy().  Convert most instances of the first form to the second form.
Requested by Chris.

llvm-svn: 96344

llvm-svn: 95828

llvm-svn: 95170

disabled by default.  This divides the existing load PRE code into 2 phases:
first it checks that it is safe to move the load to each of the predecessors
where it is unavailable, and then if it is safe, the code is changed to move
the load.  Radar 7571861.

llvm-svn: 95007

unconditionally.  Besides checking the offset, also check that the underlying
object is aligned as much as the load itself.

llvm-svn: 94875

indices are safe if the result is known to be within the bounds of the
underlying object.

llvm-svn: 94829

already checked that TmpBB->getSinglePredecessor() is non-null.

llvm-svn: 94451

llvm-svn: 93693

non-zero trip count. Use SmallVector's pop_back_val().

llvm-svn: 92734

llvm-svn: 92613

non-templated IRBuilderBase class.  Move that large CreateGlobalString
out of line, eliminating the need to #include GlobalVariable.h in IRBuilder.h

llvm-svn: 92227

instead of stored.  This reduces memdep memory usage, and also eliminates a bunch of
weakvh's.  This speeds up gvn on gcc.c-torture/20001226-1.c from 23.9s to 8.45s (2.8x)
on a different machine than earlier.

llvm-svn: 91885

load to avoid even messing around with SSAUpdate at all.  In this case (which
is very common, we can just use the input value directly).

This speeds up GVN time on gcc.c-torture/20001226-1.c from 36.4s to 16.3s,
which still isn't great, but substantially better and this is a simple speedup
that applies to lots of different cases.

llvm-svn: 91851

llvm-svn: 91849

llvm-svn: 91666

isPodLike type trait.  This is a generally useful type trait for
more than just DenseMap, and we really care about whether something
acts like a pod, not whether it really is a pod.

llvm-svn: 91421

value size.  This only manifested when memdep inprecisely returns clobber,
which is do to a caching issue in the PR5744 testcase.  We can 'efficiently
emulate' this by using '-no-aa'

llvm-svn: 91004

llvm-svn: 90999

clobbers to forward pieces of large stores to small loads, we need to consider
the properly phi translated pointer in the store block.

llvm-svn: 90978

implicitly constant folds.

llvm-svn: 90977

to require the load ty/ptr to be passed in, no functionality change.

llvm-svn: 90960

and pointer instead of the load.  No functionality change.

llvm-svn: 90959

own small class.  No functionality change.

llvm-svn: 90956

llvm-svn: 90929

phi translation of complex expressions like &A[i+1].  This has the
following benefits:

1. The phi translation logic is all contained in its own class with
   a strong interface and verification that it is self consistent.

2. The logic is more correct than before.  Previously, if intermediate
   expressions got PHI translated, we'd miss the update and scan for
   the wrong pointers in predecessor blocks.  @phi_trans2 is a testcase
   for this.

3. We have a lot less code in memdep.

We can handle phi translation across blocks of things like @phi_trans3,
which is pretty insane :).

This patch should fix the miscompiles of 255.vortex, and I tested it 
with a bootstrap of llvm-gcc, llvm-test and dejagnu of course.

llvm-svn: 90926

because clang lowers nontrivial automatic struct/array inits to memcpy from
a global array.

llvm-svn: 90698

llvm-svn: 90697

short x(short *A) {
  memset(A, 1, sizeof(*A)*100);
  return A[42];
}

to 'return 257' instead of doing the load.  

llvm-svn: 90695

llvm-svn: 90408

per Chris' comments.  Adjust testcases to match.

llvm-svn: 90304