diff --git a/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp b/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp
index 93b8e3fd..f610daa9 100644
--- a/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp
+++ b/src/dynarmic/backend/arm64/emit_arm64_data_processing.cpp
@@ -932,42 +932,37 @@ void EmitIR<IR::Opcode::Not64>(oaknut::CodeGenerator& code, EmitContext& ctx, IR
 
 template<>
 void EmitIR<IR::Opcode::SignExtendByteToWord>(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst) {
-    (void)code;
-    (void)ctx;
-    (void)inst;
-    ASSERT_FALSE("Unimplemented");
+    EmitTwoOp<32>(
+        code, ctx, inst,
+        [&](auto& Wresult, auto& Woperand) { code.SXTB(Wresult, Woperand); });
 }
 
 template<>
 void EmitIR<IR::Opcode::SignExtendHalfToWord>(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst) {
-    (void)code;
-    (void)ctx;
-    (void)inst;
-    ASSERT_FALSE("Unimplemented");
+    EmitTwoOp<32>(
+        code, ctx, inst,
+        [&](auto& Wresult, auto& Woperand) { code.SXTH(Wresult, Woperand); });
 }
 
 template<>
 void EmitIR<IR::Opcode::SignExtendByteToLong>(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst) {
-    (void)code;
-    (void)ctx;
-    (void)inst;
-    ASSERT_FALSE("Unimplemented");
+    EmitTwoOp<64>(
+        code, ctx, inst,
+        [&](auto& Xresult, auto& Xoperand) { code.SXTB(Xresult, Xoperand->toW()); });
 }
 
 template<>
 void EmitIR<IR::Opcode::SignExtendHalfToLong>(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst) {
-    (void)code;
-    (void)ctx;
-    (void)inst;
-    ASSERT_FALSE("Unimplemented");
+    EmitTwoOp<64>(
+        code, ctx, inst,
+        [&](auto& Xresult, auto& Xoperand) { code.SXTH(Xresult, Xoperand->toW()); });
 }
 
 template<>
 void EmitIR<IR::Opcode::SignExtendWordToLong>(oaknut::CodeGenerator& code, EmitContext& ctx, IR::Inst* inst) {
-    (void)code;
-    (void)ctx;
-    (void)inst;
-    ASSERT_FALSE("Unimplemented");
+    EmitTwoOp<64>(
+        code, ctx, inst,
+        [&](auto& Xresult, auto& Xoperand) { code.SXTW(Xresult, Xoperand->toW()); });
 }
 
 template<>