the inserted INSERT_SUBREGs after us.

llvm-svn: 106345

- This fixed a number of bugs in if-converter, tail merging, and post-allocation
  scheduler. If-converter now runs branch folding / tail merging first to
  maximize if-conversion opportunities.
- Also changed the t2IT instruction slightly. It now defines the ITSTATE
  register which is read by instructions in the IT block.
- Added Thumb2 specific hazard recognizer to ensure the scheduler doesn't
  change the instruction ordering in the IT block (since IT mask has been
  finalized). It also ensures no other instructions can be scheduled between
  instructions in the IT block.

This is not yet enabled.

llvm-svn: 106344

llvm-svn: 106342

instructions, but it doesn't really understand live ranges, so the first
INSERT_SUBREG uses an implicitly defined register.

Fix it in LiveVariableAnalysis by adding the <undef> flag.

llvm-svn: 106333

llvm-svn: 106330

llvm-svn: 106324

Teach iff-converter to properly count # of dups. It was not skipping over dbg_value's which resulted in non-duplicated instructions being deleted. rdar://8104384.

llvm-svn: 106323

entries used by llvm-gcc. *_[U]MIN and such can be added later if needed.

This enables the front ends to simplify handling of the atomic intrinsics by
removing the target-specific decision about which targets can handle the
intrinsics.

llvm-svn: 106321

std::vector.

llvm-svn: 106298

MachineRegisterInfo doesn't have to confusingly allocate an extra
entry.

llvm-svn: 106296

so when IfConverter::CopyAndPredicateBlock checks to see if it should ignore
an instruction because it is a branch, it should not check if the branch is
predicated.

This case (when IgnoreBr is true) is only relevant from IfConvertTriangle,
where new branches are inserted after the block has been copied and predicated.
If the original branch is not removed, we end up with multiple conditional
branches (possibly conflicting) at the end of the block.  Aside from any
immediate errors resulting from that, this confuses the AnalyzeBranch functions
so that the branches are not analyzable.  That in turn causes the IfConverter to
think that the "Simple" pattern can be applied, and things go downhill fast
because the "Simple" pattern does _not_ apply if the block can fall through.

This is pretty fragile.  If there are other degenerate cases where AnalyzeBranch
fails, but where the block may still fall through, the IfConverter should not
perform its "Simple" if-conversion.  But, I don't know how to do that with the
current AnalyzeBranch interface, so for now, the best thing seems to be to
avoid creating branches that AnalyzeBranch cannot handle.

Evan, please review!

llvm-svn: 106291

llvm-svn: 106287

llvm-svn: 106286

switch from this:

  if (TimePassesIsEnabled) {
    NamedRegionTimer T(Name, GroupName);
    do_something();
  } else {
    do_something(); // duplicate the code, this time without a timer!
  }

to this:

  {
    NamedRegionTimer T(Name, GroupName, TimePassesIsEnabled);
    do_something();
  }

llvm-svn: 106285

the old one.

llvm-svn: 106284

Don't replace the old DbgInfo with a new one when clear() on the
old one is sufficient.

llvm-svn: 106283

SDNode *, since it doesn't care about the ResNo value.

llvm-svn: 106282

llvm-svn: 106279

llvm-svn: 106278

which is faster, simpler, and less surprising.

llvm-svn: 106263

llvm-svn: 106256

addresses a longstanding deficiency noted in many FIXMEs scattered
across all the targets.

This effectively moves the problem up one level, replacing eleven
FIXMEs in the targets with eight FIXMEs in CodeGen, plus one path
through FastISel where we actually supply a DebugLoc, fixing Radar
7421831.

llvm-svn: 106243

for correctness' sake, it should be there.

llvm-svn: 106229

for the moment. The implementation of the libcall will follow.

Currently, the llvm-gcc knows when the intrinsics can be correctly handled by
the back end and only generates them in those cases, issuing libcalls directly
otherwise. That's too much coupling. The intrinsics should always be
generated and the back end decide how to handle them, be it with a libcall,
inline code, or whatever. This patch is a step in that direction.

rdar://8097623

llvm-svn: 106227

sets the legalize action to Expand.

llvm-svn: 106203

LiveVariableAnalysis was a bit picky about a register only being redefined once,
but that really isn't necessary.

Here is an example of chained INSERT_SUBREGs that we can handle now:

68      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1028<kill>, 14
                register: %reg1040 +[70,134:0)
76      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1029<kill>, 13
                register: %reg1040 replace range with [70,78:1) RESULT: %reg1040,0.000000e+00 = [70,78:1)[78,134:0)  0@78-(134) 1@70-(78)
84      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1030<kill>, 12
                register: %reg1040 replace range with [78,86:2) RESULT: %reg1040,0.000000e+00 = [70,78:1)[78,86:2)[86,134:0)  0@86-(134) 1@70-(78) 2@78-(86)
92      %reg1040<def> = INSERT_SUBREG %reg1040, %reg1031<kill>, 11
                register: %reg1040 replace range with [86,94:3) RESULT: %reg1040,0.000000e+00 = [70,78:1)[78,86:2)[86,94:3)[94,134:0)  0@94-(134) 1@70-(78) 2@78-(86) 3@86-(94)

rdar://problem/8096390

llvm-svn: 106152

llvm-svn: 106126

llvm-svn: 106119

Make post-ra scheduling, anti-dep breaking, and register scavenger (conservatively) aware of predicated instructions. This enables ARM to move if-conversion before post-ra scheduler.

llvm-svn: 106091

This speeds up local variable handling in DwarfDebug.

llvm-svn: 106075

llvm-svn: 106073

will conflict with another live range. The place which creates this scenerio is
the code in X86 that lowers a select instruction by splitting the MBBs. This
eliminates the need to check from the bottom up in an MBB for live pregs.

llvm-svn: 106066

llvm-svn: 106063

llvm-svn: 106057

Please use the fast allocator instead.

llvm-svn: 106051

llvm-svn: 106038

llvm-svn: 106027

llvm-svn: 106024

SimpleRegisterCoalescing::JoinIntervals() uses CoalescerPair to determine if a
copy is coalescable, and in very rare cases it can return true where LHS is not
live - the coalescable copy can come from an alias of the physreg in LHS.

llvm-svn: 106021

llvm-svn: 106015