Add instrumentation to VM builtins

* libguile/intrinsics.h: Add "intrinsic" for handle-interrupts code.
  Unlike the other intrinsics, this one isn't a function.
* libguile/programs.c (try_parse_arity): Add cases for instructions used
  in VM builtins.
  (scm_primitive_call_ip): Return #f if call-ip not found.
* libguile/vm-engine.c (handle-interrupts): Get code from intrinsics.
* libguile/vm.c
* libguile/vm.c (instrumented_code, define_vm_builtins): Add
  instrumentation to the builtins, so that they can be JIT-compiled.
  (INIT_BUILTIN): Remove min-arity setting; the fallback min-arity
  interpreter should figure it out.
  (scm_bootstrap_vm): Call the new define_vm_builtins function.
* libguile/gsubr.c (primitive_call_ip): Return 0 if call IP not found.
  (primitive_subr_idx): Interpret call ip == 0 as not-a-subr.
* module/system/vm/program.scm (program-arguments-alist): Allow a #f
  call-ip.

1 files changed, 5 insertions, 2 deletions

diff --git a/libguile/gsubr.c b/libguile/gsubr.c
index 227796e33..2384776e0 100644
--- a/libguile/gsubr.c
+++ b/libguile/gsubr.c
@@ -400,7 +400,7 @@ primitive_call_ip (const uint32_t *code)
           code -= 1;
           break;
         default:
-          abort ();
+          return 0;
         }
     }
 }
@@ -410,8 +410,11 @@ static const uint32_t NOT_A_SUBR_CALL = 0xffffffff;
 static uint32_t
 primitive_subr_idx (const uint32_t *code)
 {
+  uint32_t word;
   uintptr_t call_ip = primitive_call_ip (code);
-  uint32_t word = ((uint32_t *) call_ip)[0];
+  if (call_ip == 0)
+    return NOT_A_SUBR_CALL;
+  word = ((uint32_t *) call_ip)[0];
   if ((word & 0xff) == scm_op_subr_call)
     {
       uint32_t idx = word >> 8;