[llvm] [RISCV][GISel] Add ISel supports for SHXADD from Zba extension (PR #67863)

[Craig Topper via llvm-commits]

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@@ -105,6 +114,127 @@ RISCVInstructionSelector::selectShiftMask(MachineOperand &Root) const {
   return {{[=](MachineInstrBuilder &MIB) { MIB.add(Root); }}};
 }
 
+// This complex pattern actually serves as a perdicate that is effectively
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topperc wrote:

predicate*

https://github.com/llvm/llvm-project/pull/67863