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

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

llvm-svn: 70244

and SCEVSignExtendExpr.

llvm-svn: 69649

the code to minimize dependencies on TargetData.

llvm-svn: 69644

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

it is not APInt clean, but even when it is it needs to be evaluated carefully
to determine whether it is actually profitable.

This fixes a crash on PR3806

llvm-svn: 67134

if needed. This simplifies the code a little, and is needed for an
upcoming refactoring.

llvm-svn: 66479

where memory access types are needed.

llvm-svn: 66470

llvm-svn: 66469

llvm-svn: 66467

Use VoidTy instead, to be properly conservative.

llvm-svn: 66463

of an instruction into a helper function.

llvm-svn: 66460

have to be done twice.

llvm-svn: 66449

llvm-svn: 66446

before it does any processing.

llvm-svn: 66443

llvm-svn: 66065

immediately obvious.

llvm-svn: 66062

to more accurately describe what it does. Expand its doxygen comment
to describe what the backedge-taken count is and how it differs
from the actual iteration count of the loop. Adjust names and
comments in associated code accordingly.

llvm-svn: 65382

handling non-constant strides. No functionality change.

llvm-svn: 65363

-full-lsr code, as well as a GCC warning.

llvm-svn: 65288

Only try to sink immediate when TLI is not null. It needs to check if immediate would fit in target addressing field.

llvm-svn: 65268

Teach LSR sink to sink the immediate portion of the common expression back into uses if they fit in address modes of all the uses.

llvm-svn: 65215

addresses, part 1. This fixes an obvious logic bug. Previously if the only
in-loop use is a PHI, it would return AllUsesAreAddresses as true.

llvm-svn: 65178

llvm-svn: 65167

llvm-svn: 65159

llvm-svn: 65157

llvm-svn: 65147

reduction of address calculations down to basic pointer arithmetic.
This is currently off by default, as it needs a few other features
before it becomes generally useful. And even when enabled, full
strength reduction is only performed when it doesn't increase
register pressure, and when several other conditions are true.

This also factors out a bunch of exisiting LSR code out of
StrengthReduceStridedIVUsers into separate functions, and tidies
up IV insertion. This actually decreases register pressure even
in non-superhero mode. The change in iv-users-in-other-loops.ll
is an example of this; there are two more adds because there are
two fewer leas, and there is less spilling.

llvm-svn: 65108

since the latter just passes a null reference when
debugging is not enabled.

llvm-svn: 65060