ThreadEdge directly.  This shares the code, but is just a refactoring.
* Make JumpThreading compute the set of loop headers and avoid threading
  across them.  This prevents jump threading from forming irreducible 
  loops (goodness) but also prevents it from threading in other cases that
  are beneficial (see the comment above FindFunctionBackedges).

llvm-svn: 70820

FindFunctionBackedges function.

llvm-svn: 70819

llvm-svn: 70661

them to bool.

llvm-svn: 70653

makes ScalarEvolution::deleteValueFromRecords, and it's code that
subtly needed to be called before ReplaceAllUsesWith, unnecessary.

It also makes ValueDeletionListener unnecessary.

llvm-svn: 70645

a default value, and will hopefully be going away soon.

llvm-svn: 70642

of returning a list of pointers to Values that are deleted. This was
unsafe, because the pointers in the list are, by nature of what
RecursivelyDeleteDeadInstructions does, always dangling. Replace this
with a simple callback mechanism. This may eventually be removed if
all clients can reasonably be expected to use CallbackVH.

Use this to factor out the dead-phi-cycle-elimination code from LSR
utility function, and generalize it to use the
RecursivelyDeleteTriviallyDeadInstructions utility function.

This makes LSR more aggressive about eliminating dead PHI cycles;
adjust tests to either be less trivial or to simply expect fewer
instructions.

llvm-svn: 70636

deleting it.  This will let ScalarEvolution be more complete about
updating its records.

llvm-svn: 70632

llvm-svn: 70630

of LSR. This makes the AddUsersIfInteresting phase of LSR a pure
analysis instead of a phase that potentially does CFG modifications.

The conditions where this code would actually perform a split are
rare, and in the cases where it actually would do a split the split
is usually undone by CodeGenPrepare, and in cases where splits
actually survive into codegen, they appear to hurt more often than
they help.

llvm-svn: 70625

target hooks canLosslesslyBitCastTo and isTruncateFree. This allows
targets to avoid worrying about handling all combinations of integer
and pointer types.

llvm-svn: 70555

llvm-svn: 70551

llvm-svn: 70546

llvm-svn: 70427

llvm-svn: 70416

llvm-svn: 70262

llvm-svn: 70247

between the comparison's iv stride and the candidate stride is
exactly -1.

llvm-svn: 70244

llvm-svn: 70054

into unsigned ones when the operands are known to have the same
sign bit value.

llvm-svn: 70053

llvm-svn: 69946

with the persistent insertion point, and change IndVars to make
use of it. This fixes a bug where IndVars was holding on to a
stale insertion point and forcing the SCEVExpander to continue to
use it.

This fixes PR4038.

llvm-svn: 69892

llvm-svn: 69844

llvm-svn: 69842

llvm-svn: 69836

Real fix for PR3549, by using caching for predecessor counts in addition to the predecessors themselves.  This halves the time
to optimize the testcase, beyond what my previous patch did.

llvm-svn: 69792

Use PredIteratorCache in LCSSA, which gives a 37% overall speedup on the testcase from PR3549.  More improvements to come.

llvm-svn: 69788

llvm-svn: 69752

llvm-svn: 69680

and SCEVSignExtendExpr.

llvm-svn: 69649

the code to minimize dependencies on TargetData.

llvm-svn: 69644

GEP's don't usually become instructions.

llvm-svn: 69631

pointer type, make sure that the pointer size is a valid sequential index type.

llvm-svn: 69574

llvm-svn: 69450

llvm-svn: 69402

Use a safer iterator interface and get rid of std C++ library misuse.
This fixes a --enable-expensive-checks problem.

llvm-svn: 69353

regression in 403.gcc in PIC_CODEGEN=1 and DISABLE_LTO=1
mode.

llvm-svn: 69344

to get the correct answer for pointer types.

llvm-svn: 69321

incoming edges for a block with many predecessors.

llvm-svn: 69312

targets with pointers larger than 64 bits, due to the code not
yet being APInt clean.

llvm-svn: 69296