Enhanced heuristic to determine the *best* register to spill. Instead of picking the register with the lowest spill weight. Consider (up to) 2 additional registers with spill weights that are close to the lowest spill weight. The one with fewest defs and uses that conflicts with the current interval (weighted by loop depth) is the spill candidate.

This is not always a win, but there are much more wins than loses and wins tend to be more noticeable.

llvm-svn: 52554

float expansion (and sometimes vector splitting too).

llvm-svn: 52548

integer of the same type.  Before it was "promotion",
but this is confusing because it is quite different
to promotion of integers.  Call it "softening" instead,
inspired by "soft float".

llvm-svn: 52546

llvm-svn: 52545

llvm-svn: 52544

getInsertedValueOperand accessors. Thanks Matthijs!

llvm-svn: 52543

instructions. Thanks to Matthijs Kooijman for pointing this out!

llvm-svn: 52542

llvm-svn: 52539

type wasn't changed.

llvm-svn: 52538

into T) when no return values are actually dead.

llvm-svn: 52537

DeadArgumentElimination and assert that the function type does not change if
nothing was changed. This should catch subtle changes in function type that are
not intended.

llvm-svn: 52536

llvm-svn: 52535

This is a fixed version that no longer uses multimap::equal_range, which
resulted in a pointer invalidation problem.

Also, DAE::InspectedFunctions was not really necessary, so it got removed.

Lastly, this version no longer applies the extra arg hack on functions who did
not have any arguments to start with.

llvm-svn: 52532

llvm-svn: 52531

types differ.  Patch by Nathan Keynes!

llvm-svn: 52527

llvm-svn: 52525

llvm-svn: 52523

llvm-svn: 52522

Change around the data structures used to store availability sets, resulting in a GVN+PRE that is faster that GVN alone was before.

llvm-svn: 52521

propagating constants across aggregate return values when
insertvalue and extractvalue are used.

llvm-svn: 52520

return statements and aggregate returns so that it handles both
correctly.

llvm-svn: 52519

llvm-svn: 52518

llvm-svn: 52517

llvm-svn: 52516

llvm-svn: 52514

llvm-svn: 52508

once benchmarking is completed.

llvm-svn: 52506

llvm-svn: 52505

llvm-svn: 52502

using BasicBlock::getInstList.

llvm-svn: 52500

This fixes a failure on povray.

llvm-svn: 52499

directly.

llvm-svn: 52498

llvm-svn: 52497

GVN expects that all inputs which to an instruction fall somewhere in the value
hierarchy, which isn't true for these.

llvm-svn: 52496

llvm-svn: 52495

llvm-svn: 52494

using getOperand() directly. This makes things work with invoke instructions as
well.

llvm-svn: 52489

this still compiles on windows - I can't test!

llvm-svn: 52488

llvm-svn: 52487

shuffle could be skipped.  The check is invalid because the loop index i 
doesn't correspond to the element actually inserted. The correct check is
already done a few lines earlier, for whether the element is already in 
the right spot, so this shouldn't have any effect on the codegen for 
code that was already correct.

llvm-svn: 52486