The common code in the post-RA scheduler to break anti-dependencies on the
critical path contained a flaw.  In the reported case, an anti-dependency
between the overlapping registers %X4 and %R4 exists:

	%X29<def> = OR8 %X4, %X4
	%R4<def>, %X3<def,dead,tied3> = LBZU 1, %X3<kill,tied1>

The unpatched code breaks the dependency by replacing %R4 and its uses
with %R3, the first register on the available list.  However, %R3 and
%X3 overlap, so this creates two overlapping definitions on the same
instruction.

The fix is straightforward, preventing selection of a register that
overlaps any other defined register on the same instruction.

The test case is reduced from the bug report, and verifies that we no
longer produce "lbzu 3, 1(3)" when breaking this anti-dependency.

llvm-svn: 173706

missed in the first pass because the script didn't yet handle include
guards.

Note that the script is now able to handle all of these headers without
manual edits. =]

llvm-svn: 169224

Allow targets to access this API. It's required for RegisterPressure.

llvm-svn: 158102

llvm-svn: 152999

No functional change was intended.

llvm-svn: 133202

llvm-svn: 132487

llvm-svn: 125232

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

breaker needs to check all definitions of the antidepenent register to
avoid multiple defs of the same new register.

llvm-svn: 118032

make sure to allocate enough space in the std::vector.

llvm-svn: 108449

llvm-svn: 108419

get *very* large, but we only need it to be the size of thenumber of pregs.

llvm-svn: 108411

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

and End arguments by-value rather than by-reference.

llvm-svn: 101830

multiple register definitions.

llvm-svn: 92864

llvm-svn: 92837

Remove some old experimental code that is no longer needed. Remove additional, speculative scheduling pass as its cost did not translate into significant performance improvement. Minor tweaks.

llvm-svn: 89471

Do a scheduling pass ignoring anti-dependencies to identify candidate registers that should be renamed.

llvm-svn: 85939

llvm-svn: 85412

Allow the aggressive anti-dep breaker to process the same region multiple times. This is necessary because new anti-dependencies are exposed when "current" ones are broken.

llvm-svn: 85166

llvm-svn: 85127