diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td
@@ -103,7 +103,7 @@
 
 } // isReturn = 1
 
-let isTrap = 1 in
+let IsCanonical = 1, isTrap = 1 in
 defm UNREACHABLE : NRI<(outs), (ins), [(trap)], "unreachable", 0x00>;
 
 } // isTerminator = 1