Remat during spilling triggers dead code elimination. If a phi-def
becomes unused, that may also cause live ranges to split into separate
connected components.

This type of splitting is different from normal live range splitting. In
particular, there may not be a common original interval.

When the split range is its own original, make sure that the new
siblings are also their own originals. The range being split cannot be
used as an original since it doesn't cover the new siblings.

llvm-svn: 134413

llvm-svn: 134412

llvm-svn: 134409

llvm-svn: 134408

Remove the assert that triggers if SuccIterator is constructed for a basic block
without a terminator instruction. Instead of triggering an assert a succ_end()
iterator is returned. This models a basic block with zero successors and allows
us to use F->viewCFG() on incompletely constructed functions.

llvm-svn: 134398

PR10267: Don't combine an equality compare with an AND into an inequality compare when the AND has more than one use.

This can pessimize code, inequalities are generally more expensive.

llvm-svn: 134379

Noticed by Benjamin Kramer!

llvm-svn: 134376

This fixes the issue noted in PR10251 where early tail dup of bbs with
indirectbr would cause a bb to be duplicated into a loop preheader
and then into its predecessors, creating phi nodes with identical
operands just before register allocation.

This helps with jsinterp.o size (__TEXT goes from 163568 to 126656)
and a bit with performance 1.005x faster on sunspider (jits still enabled).

The result on webkit with the jit disabled is more significant: 1.021x faster.

llvm-svn: 134372

HasIndirectbr variable to be just that. No functionality change.

llvm-svn: 134371

llvm-svn: 134370

A split point inserted in a block with a landing pad successor may be
hoisted above the call to ensure that it dominates all successors. The
code that handles the rest of the basic block must take this into
account.

I am not including a test case, it would be very fragile. PR10244 comes
from building clang with exceptions enabled.

llvm-svn: 134369

This is what both the ABI and clang says.

llvm-svn: 134367

llvm-svn: 134366

llvm-svn: 134364

makes one of the tests actually mean something (as the string 'add' will
always appear in the output of this file).

llvm-svn: 134358

a file descriptor.

llvm-svn: 134355

desired result based on the comments in the file.

llvm-svn: 134354

llvm-svn: 134353

llvm-svn: 134352

llvm-svn: 134351

llvm-svn: 134350

llvm-svn: 134349

llvm-svn: 134348

llvm-svn: 134346

llvm-svn: 134345

llvm-svn: 134344

llvm-svn: 134343

llvm-svn: 134342

llvm-svn: 134341

llvm-svn: 134340

llvm-svn: 134339

llvm-svn: 134338

llvm-svn: 134337

llvm-svn: 134336

llvm-svn: 134335

llvm-svn: 134334

llvm-svn: 134333

llvm-svn: 134332

llvm-svn: 134331

individual cases, while hard coding less about registers in use.

llvm-svn: 134330