[InstCombine] Minor optimization for bswap with binary ops
Added instcombine optimizations for BSWAP with AND/OR/XOR ops:
OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) )
OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) )
Since its just a one liner, I've also added BSWAP to the DAGCombiner equivalent as well:
fold (OP (bswap x), (bswap y)) -> (bswap (OP x, y))
Refactored bswap-fold tests to use FileCheck instead of just checking that the bswaps had gone.
Differential Revision: http://reviews.llvm.org/D6407
llvm-svn: 223349
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 7347111..cbae055 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -2526,6 +2526,7 @@
// fold (OP (zext x), (zext y)) -> (zext (OP x, y))
// fold (OP (sext x), (sext y)) -> (sext (OP x, y))
// fold (OP (aext x), (aext y)) -> (aext (OP x, y))
+ // fold (OP (bswap x), (bswap y)) -> (bswap (OP x, y))
// fold (OP (trunc x), (trunc y)) -> (trunc (OP x, y)) (if trunc isn't free)
//
// do not sink logical op inside of a vector extend, since it may combine
@@ -2533,6 +2534,7 @@
EVT Op0VT = N0.getOperand(0).getValueType();
if ((N0.getOpcode() == ISD::ZERO_EXTEND ||
N0.getOpcode() == ISD::SIGN_EXTEND ||
+ N0.getOpcode() == ISD::BSWAP ||
// Avoid infinite looping with PromoteIntBinOp.
(N0.getOpcode() == ISD::ANY_EXTEND &&
(!LegalTypes || TLI.isTypeDesirableForOp(N->getOpcode(), Op0VT))) ||