Simplify the spill weight calculation a bit by bypassing
getApproximateInstructionCount() and using LiveInterval::getSize() directly.
This changes the computed spill weights, but only by a constant factor in each
function. It should not affect how spill weights compare against each other, and
so it shouldn't affect code generation.

llvm-svn: 125530

section.

llvm-svn: 125526

Fix PR8854. Track inserted copies to avoid read before write. Sorry, it's hard to reduce a sensible small test case.

llvm-svn: 125523

builders unhappy.

llvm-svn: 125504

llvm-svn: 125490

idiom.  Change various clients to simplify their code.

llvm-svn: 125487

vector fp conversions.

llvm-svn: 125482

llvm-svn: 125481

llvm-svn: 125477

llvm-svn: 125476

have their low bits set to zero.  This allows us to optimize
out explicit stack alignment code like in stack-align.ll:test4 when
it is redundant.

Doing this causes the code generator to start turning FI+cst into
FI|cst all over the place, which is general goodness (that is the
canonical form) except that various pieces of the code generator
don't handle OR aggressively.  Fix this by introducing a new
SelectionDAG::isBaseWithConstantOffset predicate, and using it
in places that are looking for ADD(X,CST).  The ARM backend in
particular was missing a lot of addressing mode folding opportunities
around OR.

llvm-svn: 125470

generating i8 shift amounts for things like i1024 types.  Add
an assert in getNode to prevent this from occuring in the future,
fix the buggy transformation, revert my previous patch, and
document this gotcha in ISDOpcodes.h

llvm-svn: 125465

the shift amounts are in a suitably wide type so that
we don't generate out of range constant shift amounts.

This fixes PR9028.

llvm-svn: 125458

is narrower than the shift register.  Doing an anyext provides undefined bits in
the top part of the register.

llvm-svn: 125457

The DAGCombiner created illegal BUILD_VECTOR operations.
The patch added a check that either illegal operations are
allowed or that the created operation is legal.

llvm-svn: 125435

that the condition is not a vector.

llvm-svn: 125398

Fix #9190

The bug happens when the DAGCombiner attempts to optimize one of the patterns
of the SUB opcode. It tries to create a zero of type v2i64. This type is legal
on 32bit machines, but the initializer of this vector (i64) is target dependent.
Currently, the initializer attempts to create an i64 zero constant, which fails.
Added a flag to tell the DAGCombiner to create a legal zero, if we require that
the pass would generate legal types.

llvm-svn: 125391

After 3-addressifying a two-address instruction, update the register maps; add a missing check when considering whether it's profitable to commute. rdar://8977508.

llvm-svn: 125259

Loop splitting is better handled by the more generic global region splitting
based on the edge bundle graph.

llvm-svn: 125243

llvm-svn: 125238

This fixes a bug where splitSingleBlocks() could split a live range after a
terminator instruction.

llvm-svn: 125237

llvm-svn: 125232

No functional changes intended.

llvm-svn: 125231

llvm-svn: 125226

llvm-svn: 125225

The tag is updated whenever the live interval union is changed, and it is tested
before using cached information.

llvm-svn: 125224

Registers are not allocated strictly in spill weight order when live range
splitting and spilling has created new shorter intervals with higher spill
weights.

When one of the new heavy intervals conflicts with a single lighter interval,
simply evict the old interval instead of trying to split the heavy one.

The lighter interval is a better candidate for splitting, it has a smaller use
density.

llvm-svn: 125151

This almost guarantees that the COPY will be coalesced.

llvm-svn: 125140

llvm-svn: 125137

The last split point can be anywhere in the block, so it interferes with the
strictly monotonic requirements of advanceTo().

llvm-svn: 125132

instruction in a basic block.

llvm-svn: 125116

This is a lot easier than trying to get kill flags right during live range
splitting and rematerialization.

llvm-svn: 125113

llvm-svn: 125109

The target hook doesn't know how to do that. (Neither do I).

llvm-svn: 125108

If a live range is used by a terminator instruction, and that live range needs
to leave the block on the stack or in a different register, it can be necessary
to have both sides of the split live at the terminator instruction.

Example:

  %vreg2 = COPY %vreg1
  JMP %vreg1

Becomes after spilling %vreg2:

  SPILL %vreg1
  JMP %vreg1

The spill doesn't kill the register as is normally the case.

llvm-svn: 125102

llvm-svn: 125101

Avoid using the same register for two def operands or and earlyclobber
def and use operand. This fixes PR8986 and improves on the prior fix
for rdar://problem/8959122.

llvm-svn: 125089

After uses of a live range are removed, recompute the live range to only cover
the remaining uses. This is necessary after rematerializing the value before
some (but not all) uses.

llvm-svn: 125058

llvm-svn: 125054

<rdar://problem/8959122> illegal register operands for UMULL instruction in cfrac nightly test
I'm stil working on a unit test, but the case is:
rx = movcc rx, r3
r2 = ldr
r2, r3 = umull r2, r2

The anti-dep breaker should not convert this into an illegal instruction:
r2, r2 = umull

llvm-svn: 124932