Implemented BitCount as an intrinsic. With unit test.
Rationale:
Recognizing this important operation as an intrinsic has
various advantages:
(1) having the no-side-effects/no-throw allows for
much more GVN/LICM/BCE.
(2) Some architectures, like x86_64, provide direct
support for this operation.
Performance improvements on X86_64:
CheckersEvalBench (32-bit bitboard): 27,210KNS -> 36,798KNS = + 35%
ReversiEvalBench (64-bit bitboard): 52,562KNS -> 89,086KNS = + 69%
Change-Id: I65d549b0469b7909b12c6611cdc34a8640a5751f
diff --git a/compiler/optimizing/intrinsics_arm.cc b/compiler/optimizing/intrinsics_arm.cc
index b1fbf28..e72f927 100644
--- a/compiler/optimizing/intrinsics_arm.cc
+++ b/compiler/optimizing/intrinsics_arm.cc
@@ -1577,10 +1577,12 @@
void IntrinsicCodeGeneratorARM::Visit ## Name(HInvoke* invoke ATTRIBUTE_UNUSED) { \
}
+UNIMPLEMENTED_INTRINSIC(IntegerBitCount)
UNIMPLEMENTED_INTRINSIC(IntegerReverse)
UNIMPLEMENTED_INTRINSIC(IntegerReverseBytes)
UNIMPLEMENTED_INTRINSIC(IntegerRotateLeft)
UNIMPLEMENTED_INTRINSIC(IntegerRotateRight)
+UNIMPLEMENTED_INTRINSIC(LongBitCount)
UNIMPLEMENTED_INTRINSIC(LongReverse)
UNIMPLEMENTED_INTRINSIC(LongReverseBytes)
UNIMPLEMENTED_INTRINSIC(LongRotateLeft)