[llvm] [AArch64] Use SVE2 bit-sel instructions for some binary patterns. (PR #147544)

[Ricardo Jesus via llvm-commits]

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@@ -4034,6 +4034,36 @@ let Predicates = [HasSVE2_or_SME] in {
   defm BSL2N_ZZZZ : sve2_int_bitwise_ternary_op<0b101, "bsl2n", AArch64bsl2n>;
   defm NBSL_ZZZZ  : sve2_int_bitwise_ternary_op<0b111, "nbsl",  AArch64nbsl>;
 
+  multiclass binary_bitwise<ValueType VT, SDPatternOperator InOp, SDPatternOperator OutOp> {
+    def : Pat<(InOp VT:$op1, VT:$op2), (OutOp $op1, $op2)>;
+
+    def : Pat<(SVEType<VT>.DSub (InOp V64:$op1, V64:$op2)),
+              (EXTRACT_SUBREG (OutOp (INSERT_SUBREG (IMPLICIT_DEF), (SVEType<VT>.DSub $op1), dsub),
+                                     (INSERT_SUBREG (IMPLICIT_DEF), (SVEType<VT>.DSub $op2), dsub)), dsub)>;
+
+    def : Pat<(SVEType<VT>.ZSub (InOp V128:$op1, V128:$op2)),
+              (EXTRACT_SUBREG (OutOp (INSERT_SUBREG (IMPLICIT_DEF), (SVEType<VT>.ZSub $op1), zsub),
+                                     (INSERT_SUBREG (IMPLICIT_DEF), (SVEType<VT>.ZSub $op2), zsub)), zsub)>;
+  }
+
+  foreach VT = [nxv16i8, nxv8i16, nxv4i32, nxv2i64] in {
+    // EON (a, b) = BSL2N (a, a, b) = BSL2N (b, b, a)
+    defm : binary_bitwise<VT, PatFrag<(ops node:$op1, node:$op2), (vnot (xor node:$op1, node:$op2))>,
+                              OutPatFrag<(ops node:$op1, node:$op2), (BSL2N_ZZZZ $op1, $op1, $op2)>>;
+
+    // NAND (a, b) = NBSL (a, b, b) = NBSL (b, a, a)
+    defm : binary_bitwise<VT, PatFrag<(ops node:$op1, node:$op2), (vnot (and node:$op1, node:$op2))>,
+                              OutPatFrag<(ops node:$op1, node:$op2), (NBSL_ZZZZ $op2, $op1, $op1)>>;
+
+    // NOR (a, b) = NBSL (a, b, a) = NBSL (b, a, b)
+    defm : binary_bitwise<VT, PatFrag<(ops node:$op1, node:$op2), (vnot (or node:$op1, node:$op2))>,
+                              OutPatFrag<(ops node:$op1, node:$op2), (NBSL_ZZZZ $op2, $op1, $op2)>>;
+
+    // ORN (a, b) = BSL2N (a, b, a)
+    defm : binary_bitwise<VT, PatFrag<(ops node:$op1, node:$op2), (or node:$op1, (vnot node:$op2))>,
+                              OutPatFrag<(ops node:$op1, node:$op2), (BSL2N_ZZZZ $op1, $op2, $op1)>>;
+  }
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rj-jesus wrote:

It wasn't obvious to me how that could be done and the order of the operands in the `*BSL*` instructions propagated, but if there's an example you could point me to, I'd be happy to give it a try.

https://github.com/llvm/llvm-project/pull/147544