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

It also makes ValueDeletionListener unnecessary.

llvm-svn: 70645

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

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

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

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

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

llvm-svn: 69296

optimizer, which just happen to frequently involve optimizing GEPs.

llvm-svn: 69295

since the operand is always a constant.

llvm-svn: 69291

new instruction with SCEVExpander::InsertCastOfTo.

llvm-svn: 69290

have pointer types, though in contrast to C pointer types, SCEV
addition is never implicitly scaled. This not only eliminates the
need for special code like IndVars' EliminatePointerRecurrence
and LSR's own GEP expansion code, it also does a better job because
it lets the normal optimizations handle pointer expressions just
like integer expressions.

Also, since LLVM IR GEPs can't directly index into multi-dimensional
VLAs, moving the GEP analysis out of client code and into the SCEV
framework makes it easier for clients to handle multi-dimensional
VLAs the same way as other arrays.

Some existing regression tests show improved optimization.
test/CodeGen/ARM/2007-03-13-InstrSched.ll in particular improved to
the point where if-conversion started kicking in; I turned it off
for this test to preserve the intent of the test.

llvm-svn: 69258

and sext over (iv | const), if a longer iv is
available.  Allow expressions to have more than
one zext/sext parent.  All from OpenSSL.

llvm-svn: 69241

if a longer iv is available.  These subscript forms are
not common; they're a bottleneck in OpenSSL.

llvm-svn: 69215

sext around sext(shorter IV + constant), using a
longer IV instead, when it can figure out the
add can't overflow.  This comes up a lot in
subscripting; mainly affects 64 bit.

llvm-svn: 69123

llvm-svn: 69121

This turns:

eq:
        %3 = icmp eq i32 %1, %2
        br label %join

ne:
        %4 = icmp ne i32 %1, %2
        br label %join

join:
        %5 = phi i1 [%3, %eq], [%4, %ne]
        br i1 %5, label %yes, label %no

=>

eq:
        %3 = icmp eq i32 %1, %2
        br i1 %3, label %yes, label %no

ne:
        %4 = icmp ne i32 %1, %2
        br i1 %4, label %yes, label %no

llvm-svn: 69102

deleting, not just the basic block.

llvm-svn: 69011

strncat :(

strncat(foo, "bar", 99)
would be optimized to
memcpy(foo+strlen(foo), "bar", 100, 1)
instead of
memcpy(foo+strlen(foo), "bar", 4, 1)"

Patch by Benjamin Kramer!

llvm-svn: 68905

code.  Patch by Benjamin Kramer!

llvm-svn: 68885