Index: llvm/lib/Target/Sparc/SparcInstrAliases.td
===================================================================
--- llvm/lib/Target/Sparc/SparcInstrAliases.td
+++ llvm/lib/Target/Sparc/SparcInstrAliases.td
@@ -492,6 +492,7 @@
 
 def : MnemonicAlias<"stuha", "stha">;
 def : MnemonicAlias<"stsha", "stha">;
+def : MnemonicAlias<"stw", "st">, Requires<[HasV9]>;
 
 def : MnemonicAlias<"lduw", "ld">, Requires<[HasV9]>;
 def : MnemonicAlias<"lduwa", "lda">, Requires<[HasV9]>;
Index: llvm/test/MC/Sparc/sparcv9-instructions.s
===================================================================
--- llvm/test/MC/Sparc/sparcv9-instructions.s
+++ llvm/test/MC/Sparc/sparcv9-instructions.s
@@ -298,3 +298,6 @@
         ! V8-NEXT: rd %pc, %o7
         ! V9: rd %pc, %o7               ! encoding: [0x9f,0x41,0x40,0x00]
         rd %pc, %o7
+
+        ! V9: st %o1, [%o0]             ! encoding: [0xd2,0x22,0x00,0x00]
+        stw %o1, [%o0]