superceded by SplitKit.

llvm-svn: 118754

benchmarks hitting an assertion.
Adds LiveIntervalUnion::collectInterferingVRegs.
Fixes "late spilling" by checking for any unspillable live vregs among
all physReg aliases.

llvm-svn: 118701

llvm-svn: 117337

Removed VNInfo::isDefAccurate(). Def "accuracy" can be checked by testing whether LiveIntervals::getInstructionFromIndex(def) returns NULL.

llvm-svn: 114791

and it will be removed shortly.

llvm-svn: 114778

The earliestStart argument is entirely specific to linear scan allocation, and
can be easily calculated by RegAllocLinearScan.

Replace std::vector with SmallVector.

llvm-svn: 111055

The spillers can pluck the analyses they need from the pass reference.

Switch some never-null pointers to references.

llvm-svn: 108969

non-const.

llvm-svn: 108734

llvm-svn: 108062

llvm-svn: 107684

llvm-svn: 107307

LocalRewriter::runOnMachineFunction uses this information to mark dead spill
slots.

This means that InlineSpiller now also works for functions that spill.

llvm-svn: 107302

llvm-svn: 107233

InlineSpiller inserts loads and spills immediately instead of deferring to
VirtRegMap. This is possible now because SlotIndexes allows instructions to be
inserted and renumbered.

This is work in progress, and is mostly a copy of TrivialSpiller so far. It
works very well for functions that don't require spilling.

llvm-svn: 107227

The VNInfo.kills vector was almost unused except for all the code keeping it
updated. The few places using it were easily rewritten to check for interval
ends instead.

The two new methods LiveInterval::killedAt and killedInRange are replacements.

This brings us down to 3 independent data structures tracking kills.

llvm-svn: 106905

vector instead. This avoids needless copying and allocation.

Add documentation.

llvm-svn: 106788

llvm-svn: 103457

doesn't have to guess.

llvm-svn: 103194

llvm-svn: 103193

llvm-svn: 103185

llvm-svn: 100703

llvm-svn: 92591

This fixes an in-place update bug where code inserted at the end of basic blocks may not be covered by existing intervals which were live across the entire block. It is also consistent with the way ranges are specified for live intervals.

llvm-svn: 91859

When a call is placed to spill an interval this spiller will first try to
break the interval up into its component values. Single value intervals and
intervals which have already been split (or are the result of previous splits)
are spilled by the default spiller.

Splitting intervals as described above may improve the performance of generated
code in some circumstances. This work is experimental however, and it still
miscompiles many benchmarks. It's not recommended for general use yet.

llvm-svn: 90951

Patch by Howard Hinnant!

llvm-svn: 90365

llvm-svn: 89422

All spiller calls in RegAllocLinearScan now go through the new Spiller interface.
The "-new-spill-framework" command line option has been removed. To use the trivial in-place spiller you should now pass "-spiller=trivial -rewriter=trivial".
(Note the trivial spiller/rewriter are only meant to serve as examples of the new in-place modification work. Enabling them will yield terrible, though hopefully functional, code).

llvm-svn: 89311

Fixed the in-place spiller and trivial rewriter, which had been broken by the recent SlotIndexes work.

llvm-svn: 89238

PreAllocSplitting is now using this API to insert code.

llvm-svn: 88725

This introduces a new pass, SlotIndexes, which is responsible for numbering
instructions for register allocation (and other clients). SlotIndexes numbering
is designed to match the existing scheme, so this patch should not cause any
changes in the generated code.

For consistency, and to avoid naming confusion, LiveIndex has been renamed
SlotIndex.

The processImplicitDefs method of the LiveIntervals analysis has been moved
into its own pass so that it can be run prior to SlotIndexes. This was
necessary to match the existing numbering scheme.

llvm-svn: 85979

llvm-svn: 83255

llvm-svn: 83254

a new class, MachineInstrIndex, which hides arithmetic details from
most clients. This is a step towards allowing the register allocator
to update/insert code during allocation.

llvm-svn: 81040

llvm-svn: 79766

as an (index,bool) pair. The bool flag records whether the kill is a
PHI kill or not. This code will be used to enable splitting of live
intervals containing PHI-kills.

A slight change to live interval weights introduced an extra spill
into lsr-code-insertion (outside the critical sections). The test 
condition has been updated to reflect this.

llvm-svn: 75097

llvm-svn: 74114

llvm-svn: 73750

llvm-svn: 73634

llvm-svn: 72729

llvm-svn: 72030