Added ROLW/RORW + SLLW/SRAW/SRLW for canCreateUndefOrPoisonForTargetNode

Author: badumbatish

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -21477,6 +21477,14 @@ bool RISCVTargetLowering::canCreateUndefOrPoisonForTargetNode(
 
   // TODO: Add more target nodes.
   switch (Op.getOpcode()) {
+  case RISCVISD::SLLW:
+  case RISCVISD::SRAW:
+  case RISCVISD::SRLW:
+  case RISCVISD::RORW:
+  case RISCVISD::ROLW:
+    // Only the lower 5 bits of RHS are read, guaranteeing the rotate/shift
+    // amount is bounds.
+    return false;
   case RISCVISD::SELECT_CC:
     // Integer select_cc cannot create poison.
     // TODO: What are the FP poison semantics?