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

llvm-svn: 90990

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

llvm-svn: 90975

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

llvm-svn: 90866

I'm not aware that this does anything significant on its own, but it's
needed for another patch that I'm working on.

llvm-svn: 90864

forwarding any uses).  GlobalDCE can also do this, but is only
run at -O3.

llvm-svn: 90850

llvm-svn: 90836

llvm-svn: 90708

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

integers that are constant except for a single bit (the same n-th bit in each).

llvm-svn: 90646

llvm-svn: 90603

llvm-svn: 90601

a compile time perf optimization to avoid a load.

llvm-svn: 90507

llvm-svn: 90487

llvm-svn: 90408

Patch by Howard Hinnant!

llvm-svn: 90365

llvm-svn: 90324

This is necessary for tests so the results are comparable.

llvm-svn: 90320

per Chris' comments.  Adjust testcases to match.

llvm-svn: 90304

llvm-svn: 90299

llvm-svn: 90298

llvm-svn: 90297

precisely, which prevents us from infinitely peeling the loop.

llvm-svn: 90211

llvm-svn: 90097

llvm-svn: 90089

fix bugs exposed by the tests.  Testcases from Alastair Lynn!

llvm-svn: 90056

llvm-svn: 90046

handle cases like this:
void test(int N, double* G) {
  long j;
  for (j = 1; j < N - 1; j++)
      G[j+1] = G[j] + G[j+1];
}

where G[1] isn't live into the loop.

llvm-svn: 90041

inserted instructions.  No functionality change until someone starts using it.

llvm-svn: 90039

to inform GVN about the newly inserted values.  This fixes 
PR5631.

llvm-svn: 90022