--- a/js/src/jit/mips-shared/Lowering-mips-shared.cpp
+++ b/js/src/jit/mips-shared/Lowering-mips-shared.cpp
@@ -577,16 +577,22 @@ LIRGeneratorMIPSShared::visitAtomicTyped
                                                    /* valueTemp= */ temp(), /* offsetTemp= */ temp(),
                                                    /* maskTemp= */ temp());
     define(lir, ins);
 }
 
 void
 LIRGeneratorMIPSShared::visitWasmTruncateToInt64(MWasmTruncateToInt64* ins)
 {
-    MOZ_CRASH("NY");
+    MOZ_CRASH("NYI");
 }
 
 void
 LIRGeneratorMIPSShared::visitInt64ToFloatingPoint(MInt64ToFloatingPoint* ins)
 {
-    MOZ_CRASH("NY");
+    MOZ_CRASH("NYI");
 }
+
+void
+LIRGeneratorMIPSShared::visitCopySign(MCopySign* ins)
+{
+    MOZ_CRASH("NYI");
+}

--- a/js/src/jit/mips-shared/Lowering-mips-shared.h
+++ b/js/src/jit/mips-shared/Lowering-mips-shared.h
@@ -90,14 +90,15 @@ class LIRGeneratorMIPSShared : public LI
     void visitAsmJSLoadFuncPtr(MAsmJSLoadFuncPtr* ins);
     void visitStoreTypedArrayElementStatic(MStoreTypedArrayElementStatic* ins);
     void visitCompareExchangeTypedArrayElement(MCompareExchangeTypedArrayElement* ins);
     void visitAtomicExchangeTypedArrayElement(MAtomicExchangeTypedArrayElement* ins);
     void visitAtomicTypedArrayElementBinop(MAtomicTypedArrayElementBinop* ins);
     void visitSubstr(MSubstr* ins);
     void visitWasmTruncateToInt64(MWasmTruncateToInt64* ins);
     void visitInt64ToFloatingPoint(MInt64ToFloatingPoint* ins);
+    void visitCopySign(MCopySign* ins);
 };
 
 } // namespace jit
 } // namespace js
 
 #endif /* jit_mips_shared_Lowering_mips_shared_h */