The value map is currently not used, all values are 'complex mapped' and
LiveIntervalMap::mapValue is used to dig them out.

This is the first step in a series changes leading to the removal of
LiveIntervalMap. Its data structures can be shared among all the live intervals
created by a split, so it is wasteful to create a copy for each.

llvm-svn: 126800

Local live range splitting is better driven by interference. This code was just
guessing.

llvm-svn: 126799

This is a waste of time since we already know how to evict all interferences
which is a better approach anyway.

llvm-svn: 126798

llvm-svn: 126794

This effectively disables the 'turbo' functionality of the greedy register
allocator where all new live ranges created by splitting would be reconsidered
as if they were originals.

There are two reasons for doing this, 1. It guarantees that the algorithm
terminates. Early versions were prone to infinite looping in certain corner
cases. 2. It is a 2x speedup. We can skip a lot of unnecessary interference
checks that won't lead to good splitting anyway.

The problem is that region splitting only gets one shot, so it should probably
be changed to target multiple physical registers at once.

Local live range splitting is still 'turbo' enabled. It only accounts for a
small fraction of compile time, so it is probably not necessary to do anything
about that.

llvm-svn: 126781

in alphabetical order.

llvm-svn: 126745

llvm-svn: 126733

llvm-svn: 126731

llvm-svn: 126684

llvm-svn: 126683

llvm-svn: 126671

patch to the front-end.  Radar 7662569.

llvm-svn: 126655

llvm-svn: 126574

llvm-svn: 126565

This follows the interface of getNodeAttributes.

llvm-svn: 126562

Add some DAGCombines for (adde 0, 0, glue), which are useful to optimize legalized code for large integer arithmetic.

1. Inform users of ADDEs with two 0 operands that it never sets carry
2. Fold other ADDs or ADDCs into the ADDE if possible

It would be neat if we could do the same thing for SETCC+ADD eventually, but we can't do that in target independent code.

llvm-svn: 126557

llvm-svn: 126526

llvm-svn: 126518

llvm-svn: 126488

llvm-svn: 126471

is possible to do better if the high bit is set in either KnownZero/KnownOne, but
in practice NumSignBits is always 1 when we are zero extending because nothing
is known about that register.

llvm-svn: 126465

actually larger.

llvm-svn: 126464

llvm-svn: 126463

New live ranges are assigned in long -> short order, but live ranges that have
been evicted at least once are deferred and assigned in short -> long order.

Also disable splitting and spilling for live ranges seen for the first time.

The intention is to create a realistic interference pattern from the heavy live
ranges before starting splitting and spilling around it.

llvm-svn: 126451

llvm-svn: 126450

Patch by Nathan Jeffords!

llvm-svn: 126425

Limit the folding of any_ext and sext  into the load operation to scalars.
Limit the active-bits trunc optimization to scalars.
Document vector trunc and vector sext in LangRef.

Similar to commit 126080 (for enabling zext).

llvm-svn: 126424

The problem was codegen guessing the wrong values and printing

	.section	.eh_frame,"aMS",@progbits,4

It is not clear at all if Codegen should try to guess, MC is the
one that should know the default flags.

llvm-svn: 126421

llvm-svn: 126397

registers at phis. This enables us to eliminate a lot of pointless zexts during
the DAGCombine phase. This fixes <rdar://problem/8760114>.

llvm-svn: 126380

llvm-svn: 126379

a block is visited before all of its predecessors.

llvm-svn: 126378

llvm-svn: 126377

and make the actual map private.

llvm-svn: 126376

allows for the information propagated across basic blocks to be merged at phis.

llvm-svn: 126375

register.

This avoids some silly stack slot shuffling when both sides of a copy get
spilled.

llvm-svn: 126353

Use DW_FORM_data2 for DW_AT_language and let users use DW_LANG_lo_user=0x8000 to DW_LANG_hi_user=0xffff range.

llvm-svn: 126339

No code will be inserted after the split point anyway.

llvm-svn: 126319

r124468.  Patch by Rafael Avila de Espindola!

llvm-svn: 126297

When a large live range is evicted, it will usually be split when it comes
around again. By deferring evicted live ranges, the splitting happens at a time
when the interference pattern is more realistic. This prevents repeated
splitting and evictions.

llvm-svn: 126282