gistfile1.txt

diff --git a/src/core/oplist b/src/core/oplist
index a476a83..f5d5d3d 100644
--- a/src/core/oplist
+++ b/src/core/oplist
@@ -593,7 +593,7 @@ continuationcontrol w(obj) r(int64) r(obj) r(obj)
 continuationinvoke  w(obj) r(obj) r(obj)
 randscale_n         w(num64) r(num64) :pure
 uniisblock          w(int64) r(str) r(int64) r(str) :pure
-assertparamcheck    r(int64) :noinline
+assertparamcheck    r(int64) :noinline :throwish
 hintfor             w(int64) r(obj) r(str)
 paramnamesused      :noinline
 getuniname          w(str) r(int64)
diff --git a/src/core/ops.c b/src/core/ops.c
index 27e4a38..5d9cb55 100644
--- a/src/core/ops.c
+++ b/src/core/ops.c
@@ -6128,7 +6128,7 @@ static MVMOpInfo MVM_op_infos[] = {
         0,
         0,
         1,
-        0,
+        2,
         { MVM_operand_read_reg | MVM_operand_int64 }
     },
     {
diff --git a/src/jit/emit_x64.dasc b/src/jit/emit_x64.dasc
index 6b72f79..b015896 100644
--- a/src/jit/emit_x64.dasc
+++ b/src/jit/emit_x64.dasc
@@ -1061,6 +1061,15 @@ void MVM_jit_emit_primitive(MVMThreadContext *tc, MVMJitGraph *jg,
         | callp &MVM_args_assert_nameds_used;
         |1:
         break;
+    case MVM_OP_assertparamcheck: {
+        MVMint16 ok = ins->operands[0].reg.orig;
+        | mov TMP1, qword WORK[ok];
+        | test TMP1, TMP1;
+        | jz >1;
+        | callp &MVM_args_bind_failed;
+        |1:
+        break;
+    }
     default:
         MVM_exception_throw_adhoc(tc, "Can't JIT opcode <%s>", ins->info->name);
     }
diff --git a/src/jit/graph.c b/src/jit/graph.c
index 64f0524..88ffcd4 100644
--- a/src/jit/graph.c
+++ b/src/jit/graph.c
@@ -697,6 +697,7 @@ static MVMint32 jgb_consume_ins(MVMThreadContext *tc, JitGraphBuilder *jgb,
     case MVM_OP_getlexstatic_o:
     case MVM_OP_getlexperinvtype_o:
     case MVM_OP_paramnamesused:
+    case MVM_OP_assertparamcheck:
         jgb_append_primitive(tc, jgb, ins);
         break;
         /* branches */