[llvm] [AArch64][SVE] Add patterns for bit-select instructions. (PR #138689)

[Paul Walker via llvm-commits]

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@@ -545,12 +545,18 @@ def AArch64umulh : PatFrag<(ops node:$op1, node:$op2),
 
 
 def AArch64bsl  : PatFrags<(ops node:$Op1, node:$Op2, node:$Op3),
-                           [(int_aarch64_sve_bsl node:$Op1, node:$Op2, node:$Op3),
-                            (AArch64bsp node:$Op3, node:$Op1, node:$Op2)]>;
+                           [(AArch64bsp node:$Op3, node:$Op1, node:$Op2),
+                            (or (and node:$Op1, node:$Op3), (and node:$Op2, (vnot node:$Op3)))]>;
 
-def AArch64nbsl : PatFrags<(ops node:$Op1, node:$Op2, node:$Op3),
-                           [(int_aarch64_sve_nbsl node:$Op1, node:$Op2, node:$Op3),
-                            (vnot (AArch64bsp node:$Op3, node:$Op1, node:$Op2))]>;
+def AArch64bsl1n : PatFrag<(ops node:$Op1, node:$Op2, node:$Op3),
+                           (AArch64bsl (vnot node:$Op1), node:$Op2, node:$Op3)>;
+
+def AArch64bsl2n : PatFrags<(ops node:$Op1, node:$Op2, node:$Op3),
+                            [(AArch64bsl node:$Op1, (vnot node:$Op2), node:$Op3),
+                             (or (and node:$Op1, node:$Op3), (vnot (or node:$Op2, node:$Op3)))]>;
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paulwalker-arm wrote:

That De Morgan has a lot to answer for :(

https://github.com/llvm/llvm-project/pull/138689