Add LIS::pruneValue() and extendToIndices(). These two functions are
used by the register coalescer when merging two live ranges requires
more than a trivial value mapping as supported by LiveInterval::join().

The pruneValue() function can remove the part of a value number that is
going to conflict in join(). Afterwards, extendToIndices can restore the
live range, using any new dominating value numbers and updating the SSA
form.

Use this complex value mapping to support merging a register into a
vector lane that has a conflicting value, but the clobbered lane is
undef.

llvm-svn: 164074

These extra operands are not needed by register allocators using
VirtRegRewriter, and RAFast don't need them any longer.

By omitting the <imp-def> operands, it becomes possible for the new
register coalescer to track which lanes are valid and which are undef.

llvm-svn: 164073

I have to work out the Target/CodeGen header dependencies
before putting this back.

llvm-svn: 164072

llvm-svn: 164065

Increase the static sizes of some SmallSets. finalizeBundle() is very frequently called for some backends, and growing into an std::set is overkill for these numbers.

llvm-svn: 164044

llvm-svn: 164043

- Preserve the original NOutVT during casting from vector to integer by
  extracting vector elements.

llvm-svn: 164042

This is used in the AMDIL and R600 backends.

llvm-svn: 164029

Disable the protection from escaped allocas in an attempt to find violating passes. This may break the buildbots. I plan to revert it in a few hours.

llvm-svn: 164024

llvm-svn: 164000

The live range of an SSA value forms a sub-tree of the dominator tree.
That means the live ranges of two values overlap if and only if the def
of one value lies within the live range of the other.

This can be used to simplify the interference checking a bit: Visit each
def in the two registers about to be joined. Check for interference
against the value that is live in the other register at the def point
only. It is not necessary to scan the set of overlapping live ranges,
this interference check can be done while computing the value mapping
required for the final live range join.

The new algorithm is prepared to handle more complicated conflict
resolution - We can allow overlapping live ranges with different values
as long as the differing lanes are undef or unused in the other
register.

The implementation in this patch doesn't do that yet, it creates code
that is nearly identical to the old algorithm's, except:

- The new stripCopies() function sees through multiple copies while
  the old RegistersDefinedFromSameValue() only can handle one.

- There are a few rare cases where the new algorithm can erase an
  IMPLICIT_DEF instuction that RegistersDefinedFromSameValue() couldn't
  handle.

llvm-svn: 163991

llvm-svn: 163974

Kill flags are removed more and more aggressively during the register
allocation passes, it is better to get information from LiveIntervals.

llvm-svn: 163972

llvm-svn: 163934

llvm-svn: 163915

llvm-svn: 163882

umulo legalization.

Fixes PR13839

llvm-svn: 163856

closer to where they're needed.

llvm-svn: 163855

- Find a legal vector type before casting and extracting element from it.
- As the new vector type may have more than 2 elements, build the final
  hi/lo pair by BFS pairing them from bottom to top.

llvm-svn: 163830

Rename the flag which protects from escaped allocas, which may come from bugs in user code or in the compiler. Also, dont assert if the protection is not enabled.

llvm-svn: 163807

by xoring the high-bit. This fails if the source operand is a vector because we need to negate
each of the elements in the vector.

Fix rdar://12281066 PR13813.

llvm-svn: 163802

llvm-svn: 163801

Stack Coloring: We have code that checks that all of the uses of allocas
are within the lifetime zone. Sometime legitimate usages of allocas are
hoisted outside of the lifetime zone. For example, GEPS may calculate the
address of a member of an allocated struct. This commit makes sure that
we only check (abort regions or assert) for instructions that read and write
memory using stack frames directly. Notice that by allowing legitimate
usages outside the lifetime zone we also stop checking for instructions
which use derivatives of allocas. We will catch less bugs in user code
and in the compiler itself.

llvm-svn: 163791

    Add some support for dealing with an object pointer on arguments.

    Part of rdar://9797999

which now supports adding the object pointer attribute to the
subprogram as it should.

llvm-svn: 163754

    
- BlockAddress has no support of BA + offset form and there is no way to
  propagate that offset into machine operand;
- Add BA + offset support and a new interface 'getTargetBlockAddress' to
  simplify target block address forming;
- All targets are modified to use new interface and X86 backend is enhanced to
  support BA + offset addressing.

llvm-svn: 163743

Remove an overly-aggressive assertion.  The code following this assertion already knows how to handle the case where DstRC was NULL, so it's not actually protecting us from anything, and this pattern can come up when using unknown_class operands in the SelectionDAG.

llvm-svn: 163736

llvm-svn: 163735

This should be done on the subprogram, not the variable itself.

llvm-svn: 163734

llvm-svn: 163721

Fix constant folding through bitcasts by no longer relying on undefined behaviour (converting NaN values between float and double).

SelectionDAG::getConstantFP(double Val, EVT VT, bool isTarget);
should not be used when Val is not a simple constant (as the comment in
SelectionDAG.h indicates). This patch avoids using this function
when folding an unknown constant through a bitcast, where it cannot be
guaranteed that Val will be a simple constant.

llvm-svn: 163703

Add a flag to disable the code that looks for allocas which escaped the lifetime regions. This is useful for debugging. No testcase because without this check we fail on assertions when finding escaped allocas.

llvm-svn: 163702

Add a function computeRegisterLiveness() to MachineBasicBlock. This uses analyzePhysReg() from r163694 to heuristically try and determine the liveness state of a physical register upon arrival at a particular instruction in a block.

The search for liveness is clipped to a specific number of instructions around the target MachineInstr, in order to avoid degenerating into an O(N^2) algorithm. It tries to use various clues about how instructions around (both before and after) a given MachineInstr use that register, to determine its state at the MachineInstr.

llvm-svn: 163695

Add an analyzePhysReg() function to MachineOperandIteratorBase that analyses an instruction's use of a physical register, analogous to analyzeVirtReg.

Rename RegInfo to VirtRegInfo so as not to be confused with the new PhysRegInfo.

llvm-svn: 163694

llvm-svn: 163687

findLastUseBefore was previous considering virtreg liveness only, leading to
incorrect live intervals for reg units when instrs with physreg operands were
moved up.
 

llvm-svn: 163685

The input program may contain intructions which are not inside lifetime
markers. This can happen due to a bug in the compiler or due to a bug in
user code (for example, returning a reference to a local variable).
This commit adds checks that all of the instructions in the function and
invalidates lifetime ranges which do not contain all of the instructions.

llvm-svn: 163678

Part of rdar://9797999

llvm-svn: 163667

"#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)"

No functional change. Update r163339.

llvm-svn: 163653

Add support in the EmitMSInlineAsmStr() function for handling integer consts.

llvm-svn: 163645

Dragonegg selfhost exposed additional cases where alloca usage moved outside of lifetime markers. Disabling the pass for now.

llvm-svn: 163623