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

llvm-svn: 118701

SlotIndexes when available.

llvm-svn: 117392

perform initialization without static constructors AND without explicit initialization
by the client.  For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve.  I hope to be able to relax
the latter requirement in the future.

llvm-svn: 116334

This helps hiding the LiveRange class which really should be private.

llvm-svn: 116244

llvm-svn: 115996

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

llvm-svn: 114791

llvm-svn: 114779

PHI elimination shouldn't require machineloopinfo since it's used at -O0. Move the requirement to LiveIntervalAnalysis instead. Note this does not change the number of times machineloopinfo is computed.

llvm-svn: 111285

llvm-svn: 110944

When the normalizeSpillWeights function was introduced, I forgot to remove this
normalization.

This change could affect register allocation. Hopefully for the better.

llvm-svn: 110119

llvm-svn: 109045

TII::isMoveInstr is going tobe completely removed.

llvm-svn: 108507

llvm-svn: 108013

inserted in a MBB, and return an already inserted MI.

This target API change is necessary to allow foldMemoryOperand to call
storeToStackSlot and loadFromStackSlot when folding a COPY to a stack slot
reference in a target independent way.

The foldMemoryOperandImpl hook is going to change in the same way, but I'll wait
until COPY folding is actually implemented. Most targets only fold copies and
won't need to specialize this hook at all.

llvm-svn: 107991

EXTRACT_SUBREG no longer appears as a machine instruction. Use COPY instead.

Add isCopy() checks in many places using isMoveInstr() and isExtractSubreg().
The isMoveInstr hook will be removed later.

llvm-svn: 107879

Fix X86InstrInfo::convertToThreeAddressWithLEA to generate COPY instead of
INSERT_SUBREG.

llvm-svn: 107878

Buildbot breakage.

llvm-svn: 107744

llvm-svn: 107732

INSERT_SUBREG will now only appear in SSA machine instructions.

Fix the handling of partial redefs in ProcessImplicitDefs. This is now relevant
since partial redef COPY instructions appear.

llvm-svn: 107726

This code is transitional, it will soon be possible to eliminate
isExtractSubreg, isInsertSubreg, and isMoveInstr in most places.

llvm-svn: 107547

llvm-svn: 106943

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

This method was always a bit too simplistic for the real world. It didn't really
deal with subregisters and such.

llvm-svn: 106781

This code path has never really been used, and we are going to be handling
spilling through the Spiller interface in the future.

llvm-svn: 106777

CoalescerPair can determine if a copy can be coalesced, and which register gets
merged away. The old logic in SimpleRegisterCoalescing had evolved into
something a bit too convoluted.

This second attempt fixes some crashes that only occurred Linux.

llvm-svn: 106769

In this case it is essential that the kill is real because the spiller will
decide to omit a spill if it thinks there is a later kill.

llvm-svn: 106751

Whiny buildbots.

llvm-svn: 106710

CoalescerPair can determine if a copy can be coalesced, and which register gets
merged away. The old logic in SimpleRegisterCoalescing had evolved into
something a bit too convoluted.

llvm-svn: 106701

instructions, but it doesn't really understand live ranges, so the first
INSERT_SUBREG uses an implicitly defined register.

Fix it in LiveVariableAnalysis by adding the <undef> flag.

llvm-svn: 106333

LiveVariableAnalysis was a bit picky about a register only being redefined once,
but that really isn't necessary.

Here is an example of chained INSERT_SUBREGs that we can handle now:

68      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1028<kill>, 14
                register: %reg1040 +[70,134:0)
76      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1029<kill>, 13
                register: %reg1040 replace range with [70,78:1) RESULT: %reg1040,0.000000e+00 = [70,78:1)[78,134:0)  0@78-(134) 1@70-(78)
84      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1030<kill>, 12
                register: %reg1040 replace range with [78,86:2) RESULT: %reg1040,0.000000e+00 = [70,78:1)[78,86:2)[86,134:0)  0@86-(134) 1@70-(78) 2@78-(86)
92      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1031<kill>, 11
                register: %reg1040 replace range with [86,94:3) RESULT: %reg1040,0.000000e+00 = [70,78:1)[78,86:2)[86,94:3)[94,134:0)  0@94-(134) 1@70-(78) 2@78-(86) 3@86-(94)

rdar://problem/8096390

llvm-svn: 106152

spills and reloads.

This means that a partial define of a register causes a reload so the other
parts of the register are preserved.

The reload can be prevented by adding an <imp-def> operand for the full
register. This is already done by the coalescer and live interval analysis where
relevant.

llvm-svn: 105369

that are aliases of the specified register.
- Rename modifiesRegister to definesRegister since it's looking a def of the
specific register or one of its super-registers. It's not looking for def of a
sub-register or alias that could change the specified register.
- Added modifiesRegister to look for defs of aliases.

llvm-svn: 104377

This reverts r104322. I think it was causing miscompilations.

llvm-svn: 104323

This correctly handles partial redefines and undef uses.

llvm-svn: 104322

<imp-def> operand for the full register. This ensures that the full physical
register is marked live after register allocation.

llvm-svn: 104320

llvm-svn: 104209

Yes, if the redef is a copy, update the old val# with the copy. But make sure to clear the copy field if the redef is not a copy.

llvm-svn: 103922

patch by Evzen Muller!

llvm-svn: 103876

llvm-svn: 103850

llvm-svn: 103410