Add a set_runcore op to switch to a different runcore.

Also support CURRENT_RUNCORE in interpinfo_s() to get the name of the current
runcore.
We need an extra op for the runcore switching, because we need to restart the
runops() loop. This can only be done in an op at the moment.

include/parrot/oplib/core_ops.h

@@ -112,6 +112,8 @@ op_lib_t *Parrot_DynOp_core_3_10_0(PARROT_INTERP, long init);
  opcode_t * Parrot_errorson_ic(opcode_t *, PARROT_INTERP);
  opcode_t * Parrot_errorsoff_i(opcode_t *, PARROT_INTERP);
  opcode_t * Parrot_errorsoff_ic(opcode_t *, PARROT_INTERP);
+ opcode_t * Parrot_set_runcore_s(opcode_t *, PARROT_INTERP);
+ opcode_t * Parrot_set_runcore_sc(opcode_t *, PARROT_INTERP);
  opcode_t * Parrot_runinterp_p_i(opcode_t *, PARROT_INTERP);
  opcode_t * Parrot_runinterp_p_ic(opcode_t *, PARROT_INTERP);
  opcode_t * Parrot_getinterp_p(opcode_t *, PARROT_INTERP);

src/interp/inter_misc.c

@@ -443,6 +443,8 @@ interpinfo_s(PARROT_INTERP, INTVAL what)
             Parrot_warn_experimental(interp, "GC_SYS_NAME option is experimental");
             return name;
         }
+        case CURRENT_RUNCORE:
+            return interp->run_core->name;
       default:
         Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_UNIMPLEMENTED,
                 "illegal argument in interpinfo");

src/ops/core.ops

@@ -1035,7 +1035,7 @@ CURRENT_SUB, CURRENT_CONT, CURRENT_OBJECT, CURRENT_LEXPAD
 
 =item B<interpinfo>(out STR, in INT)
 
-EXECUTABLE_FULLNAME, EXECUTABLE_BASENAME, RUNTIME_PREFIX
+EXECUTABLE_FULLNAME, EXECUTABLE_BASENAME, RUNTIME_PREFIX, CURRENT_RUNCORE
 
 =back
 
@@ -1130,6 +1130,19 @@ inline op errorsoff(in INT) {
     PARROT_ERRORS_off(interp, $1);
 }
 
+=item B<set_runcore>(in STR)
+
+Switch the current runcore to the one with the specified name.
+Needs to be an op, as we need to restart the runops() call.
+You can get the name of the current runcore with the interpinfo op.
+
+=cut
+
+inline op set_runcore(in STR) {
+    Parrot_runcore_switch(interp, $1);
+    restart NEXT();
+}
+
 ########################################
 
 =item B<runinterp>(invar PMC, in LABEL)

t/compilers/opsc/06-opsfile.t

@@ -21,7 +21,7 @@ my @ops := $f.ops;
 say( "# Parsed " ~ +@ops);
 # There is more than 200 ops in this 2 files.
 # Feel free to update number if you change them.
-ok(+@ops == 271, "Ops parsed correctly");
+ok(+@ops == 273, "Ops parsed correctly");
 say('# ' ~ +@ops);
 
 my $op := @ops[0];