llvm-svn: 129970

An exception is thrown via a call to _cxa_throw, which we don't expect to
return. Therefore, the "true" part of the invoke goes to a BB that has
'unreachable' as its only instruction. This is lowered into an empty MachineBB.
The landing pad for this invoke, however, is directly after the "true" MBB.
When the empty MBB is removed, the landing pad is directly below the BB with the
invoke call. The unconditional branch is removed and then the two blocks are
merged together.

The testcase is too big for a regression test.
<rdar://problem/9305728>

llvm-svn: 129965

llvm-svn: 129938

llvm-svn: 129928

These intervals are allocatable immediately after splitting, but they may be
evicted because of later splitting. This is rare, but when it happens they
should be split again.

The remainder intervals that cannot be allocated after splitting still move
directly to spilling.

SplitEditor::finish can optionally provide a mapping from new live intervals
back to the original interval indexes returned by openIntv().

Each original interval index can map to multiple new intervals after connected
components have been separated. Dead code elimination may also add existing
intervals to the list.

The reverse mapping allows the SplitEditor client to treat the new intervals
differently depending on the split region they came from.

llvm-svn: 129925

llvm-svn: 129921

which broke a couple GCC test suite tests at -O0.

llvm-svn: 129914

llvm-svn: 129883

TII::isTriviallyReMaterializable() shouldn't depend on any properties of the
register being defined by the instruction. Rematerialization is going to create
a new virtual register anyway.

llvm-svn: 129882

On the x86-64 and thumb2 targets, some registers are more expensive to encode
than others in the same register class.

Add a CostPerUse field to the TableGen register description, and make it
available from TRI->getCostPerUse. This represents the cost of a REX prefix or a
32-bit instruction encoding required by choosing a high register.

Teach the greedy register allocator to prefer cheap registers for busy live
ranges (as indicated by spill weight).

llvm-svn: 129864

llvm-svn: 129858

llvm-svn: 129844

manually and pass all (now) 4 arguments to the mul libcall. Add a new
ExpandLibCall for just this (copied gratuitously from type legalization).

Fixes rdar://9292577

llvm-svn: 129842

triple component.

llvm-svn: 129838

 - There is a minor semantic change here (evidenced by the test change) for
   Darwin triples that have no version component. I debated changing the default
   behavior of isOSVersionLT, but decided it made more sense for triples to be
   explicit.

llvm-svn: 129802

llvm-svn: 129796

Add a avoidWriteAfterWrite() target hook to identify register classes that
suffer from write-after-write hazards. For those register classes, try to avoid
writing the same register in two consecutive instructions.

This is currently disabled by default.  We should not spill to avoid hazards!
The command line flag -avoid-waw-hazard can be used to enable waw avoidance.

llvm-svn: 129772

This means that the new register allocator can be used with 'clang -mllvm -regalloc=greedy'.

llvm-svn: 129764

unnecessary work where possible.

llvm-svn: 129763

llvm-svn: 129761

en-mass for C++ PODs.  On my c++ test file, this cuts the fast isel rejects by 10x 
and shrinks the generated .s file by 5%

llvm-svn: 129755

llvm-svn: 129720

llvm-svn: 129715

the spilled register.

This is quite common on ARM now that some stores have early-clobber defines.

llvm-svn: 129714

registers for fast allocation a different way. This has us updating
used registers only when we're using that exact register.

Fixes rdar://9207598

llvm-svn: 129711

this fixes a few rejects on c++ iterator loops.

llvm-svn: 129694

llvm-svn: 129693

2. implement rdar://9289501 - fast isel should fold trivial multiplies to shifts
3. teach tblgen to handle shift immediates that are different sizes than the 
   shifted operands, eliminating some code from the X86 fast isel backend.
4. Have FastISel::SelectBinaryOp use (the poorly named) FastEmit_ri_ function
   instead of FastEmit_ri to simplify code.

llvm-svn: 129666

less trivial things) into a dummy lea.  Before we generated:

_test:                                  ## @test
	movq	_G@GOTPCREL(%rip), %rax
	leaq	(%rax), %rax
	ret

now we produce:

_test:                                  ## @test
	movq	_G@GOTPCREL(%rip), %rax
	ret

This is part of rdar://9289558

llvm-svn: 129662

The basic issue here is that bottom-up isel is matching the branch
and compare, and was failing to fold the load into the branch/compare
combo.  Fixing this (by allowing folding into any instruction of a
sequence that is selected) allows us to produce things like:


cmpb    $0, 52(%rax)
je      LBB4_2

instead of:

movb    52(%rax), %cl
cmpb    $0, %cl
je      LBB4_2

This makes the generated -O0 code run a bit faster, but also speeds up
compile time by putting less pressure on the register allocator and 
generating less code.

This was one of the biggest classes of missing load folding.  Implementing
this shrinks 176.gcc's c-decl.s (as a random example) by about 4% in (verbose-asm)
line count.

llvm-svn: 129656

which don't need to check for falling off the end of a block *and* end of phi
nodes, since terminators are never phis.

llvm-svn: 129655

allowing us to fold the immediate into the 'and' in this case:

int test1(int i) {
  return 8&i;
}

llvm-svn: 129653

Returning a new node makes the code try to replace the old node, which
in the included testcase is killed by CSE.

llvm-svn: 129650

For further information on this particular issue see: http://connect.microsoft.com/VisualStudio/feedback/details/520043/error-converting-from-null-to-a-pointer-type-in-std-pair

llvm-svn: 129642

llvm-svn: 129639

  error in foo.o; no .eh_frame_hdr table will be created.

llvm-svn: 129635

Fix divmod libcall lowering. Convert to {S|U}DIVREM first and then expand the node to a libcall. rdar://9280991

llvm-svn: 129633

Introduce support to encode Objective-C property information in debugging information generated for an interface.

llvm-svn: 129624

llvm-svn: 129600

The transferValues() function can now handle both singly and multiply defined
values, as long as the resulting live range is known. Only rematerialized values
have their live range recomputed by extendRange().

The updateSSA() function can now insert PHI values in bulk across multiple
values in multiple target registers in one pass. The list of blocks received
from transferValues() is in layout order which seems to work well for the
iterative algorithm. Blocks from extendRange() are still in reverse BFS order,
but this function is used so rarely now that it doesn't matter.

llvm-svn: 129580