Better debug info for struct bytecode.

--debug-dump-disasm produces more comprehensible output now.

bytecode.c

@@ -16,12 +16,24 @@ static int bytecode_operation_length(uint16_t* codeptr) {
 
 void dump_disassembly(int indent, struct bytecode* bc) {
   if (bc->nclosures > 0) {
-    printf("%*s[params: %d]\n", indent, "", bc->nclosures);
+    printf("%*s[params: ", indent, "");
+    jv params = jv_object_get(jv_copy(bc->debuginfo), jv_string("params"));
+    for (int i=0; i<bc->nclosures; i++) {
+      if (i) printf(", ");
+      jv name = jv_array_get(jv_copy(params), i);
+      printf("%s", jv_string_value(name));
+      jv_free(name);
+    }
+    jv_free(params);
+    printf("]\n");
   }
   dump_code(indent, bc);
   for (int i=0; i<bc->nsubfunctions; i++) {
-    printf("%*ssubfn[%d]:\n", indent, "", i);
-    dump_disassembly(indent+2, bc->subfunctions[i]);
+    struct bytecode* subfn = bc->subfunctions[i];
+    jv name = jv_object_get(jv_copy(subfn->debuginfo), jv_string("name"));
+    printf("%*s%s:%d:\n", indent, "", jv_string_value(name), i);
+    jv_free(name);
+    dump_disassembly(indent+2, subfn);
   }
 }
 
@@ -35,6 +47,14 @@ void dump_code(int indent, struct bytecode* bc) {
   }
 }
 
+static struct bytecode* getlevel(struct bytecode* bc, int level) {
+  while (level > 0) {
+    bc = bc->parent;
+    level--;
+  }
+  return bc;
+}
+
 void dump_operation(struct bytecode* bc, uint16_t* codeptr) {
   int pc = codeptr - bc->code;
   printf("%04d ", pc);
@@ -46,15 +66,28 @@ void dump_operation(struct bytecode* bc, uint16_t* codeptr) {
       for (int i=0; i<imm+1; i++) {
         uint16_t level = bc->code[pc++];
         uint16_t idx = bc->code[pc++];
+        jv name;
         if (idx & ARG_NEWCLOSURE) {
-          printf(" subfn[%d]", idx & ~ARG_NEWCLOSURE);
+          idx &= ~ARG_NEWCLOSURE;
+          name = jv_object_get(jv_copy(getlevel(bc,level)->subfunctions[idx]->debuginfo), 
+                               jv_string("name"));
         } else {
-          printf(" param[%d]", idx);
+          name = jv_array_get(jv_object_get(jv_copy(getlevel(bc,level)->debuginfo), 
+                                            jv_string("params")), idx);
         }
+        printf(" %s:%d",
+               jv_string_value(name),
+               idx);
+        jv_free(name);
         if (level) {
           printf("^%d", level);
         }
       }
+    } else if (op->op == CALL_BUILTIN) {
+      int func = bc->code[pc++];
+      jv name = jv_array_get(jv_copy(bc->globals->cfunc_names), func);
+      printf(" %s", jv_string_value(name));
+      jv_free(name);
     } else if (op->flags & OP_HAS_BRANCH) {
       printf(" %04d", pc + imm);
     } else if (op->flags & OP_HAS_CONSTANT) {
@@ -62,7 +95,11 @@ void dump_operation(struct bytecode* bc, uint16_t* codeptr) {
       jv_dump(jv_array_get(jv_copy(bc->constants), imm), 0);
     } else if (op->flags & OP_HAS_VARIABLE) {
       uint16_t v = bc->code[pc++];
-      printf(" v%d", v);
+      jv name = jv_array_get(jv_object_get(jv_copy(getlevel(bc,imm)->debuginfo), jv_string("locals")), v);
+      printf(" $%s:%d", 
+             jv_string_value(name), 
+             v);
+      jv_free(name);
       if (imm) {
         printf("^%d", imm);
       }
@@ -74,6 +111,7 @@ void dump_operation(struct bytecode* bc, uint16_t* codeptr) {
 
 void symbol_table_free(struct symbol_table* syms) {
   jv_mem_free(syms->cfunctions);
+  jv_free(syms->cfunc_names);
   jv_mem_free(syms);
 }
 
@@ -85,5 +123,6 @@ void bytecode_free(struct bytecode* bc) {
   if (!bc->parent)
     symbol_table_free(bc->globals);
   jv_mem_free(bc->subfunctions);
+  jv_free(bc->debuginfo);
   jv_mem_free(bc);
 }

bytecode.h

@@ -10,6 +10,7 @@
 struct symbol_table {
   struct cfunction* cfunctions;
   int ncfunctions;
+  jv cfunc_names;
 };
 
 // The bytecode format matters in:
@@ -33,6 +34,8 @@ struct bytecode {
   int nsubfunctions;
 
   struct bytecode* parent;
+
+  jv debuginfo;
 };
 
 void dump_disassembly(int, struct bytecode* code);

compile.c

@@ -526,6 +526,7 @@ static int compile(struct locfile* locations, struct bytecode* bc, block b) {
   bc->nsubfunctions = 0;
   errors += expand_call_arglist(locations, &b);
   b = BLOCK(b, gen_op_simple(RET));
+  jv localnames = jv_array();
   for (inst* curr = b.first; curr; curr = curr->next) {
     if (!curr->next) assert(curr == b.last);
     int length = opcode_describe(curr->op)->length;
@@ -543,6 +544,7 @@ static int compile(struct locfile* locations, struct bytecode* bc, block b) {
     if ((opcode_describe(curr->op)->flags & OP_HAS_VARIABLE) &&
         curr->bound_by == curr) {
       curr->imm.intval = var_frame_idx++;
+      localnames = jv_array_append(localnames, jv_string(curr->symbol));
     }
 
     if (curr->op == CLOSURE_CREATE) {
@@ -552,10 +554,13 @@ static int compile(struct locfile* locations, struct bytecode* bc, block b) {
     if (curr->op == CLOSURE_CREATE_C) {
       assert(curr->bound_by == curr);
       int idx = bc->globals->ncfunctions++;
+      bc->globals->cfunc_names = jv_array_append(bc->globals->cfunc_names,
+                                                 jv_string(curr->symbol));
       bc->globals->cfunctions[idx] = *curr->imm.cfunc;
       curr->imm.intval = idx;
     }
   }
+  bc->debuginfo = jv_object_set(bc->debuginfo, jv_string("locals"), localnames);
   if (bc->nsubfunctions) {
     bc->subfunctions = jv_mem_alloc(sizeof(struct bytecode*) * bc->nsubfunctions);
     for (inst* curr = b.first; curr; curr = curr->next) {
@@ -565,12 +570,16 @@ static int compile(struct locfile* locations, struct bytecode* bc, block b) {
         subfn->globals = bc->globals;
         subfn->parent = bc;
         subfn->nclosures = 0;
+        subfn->debuginfo = jv_object_set(jv_object(), jv_string("name"), jv_string(curr->symbol));
+        jv params = jv_array();
         for (inst* param = curr->arglist.first; param; param = param->next) {
           assert(param->op == CLOSURE_PARAM);
           assert(param->bound_by == param);
           param->imm.intval = subfn->nclosures++;
           param->compiled = subfn;
+          params = jv_array_append(params, jv_string(param->symbol));
         }
+        subfn->debuginfo = jv_object_set(subfn->debuginfo, jv_string("params"), params);
         errors += compile(locations, subfn, curr->subfn);
         curr->subfn = gen_noop();
       }
@@ -638,6 +647,8 @@ int block_compile(block b, struct locfile* locations, struct bytecode** out) {
   int ncfunc = count_cfunctions(b);
   bc->globals->ncfunctions = 0;
   bc->globals->cfunctions = jv_mem_alloc(sizeof(struct cfunction) * ncfunc);
+  bc->globals->cfunc_names = jv_array();
+  bc->debuginfo = jv_object_set(jv_object(), jv_string("name"), jv_null());
   int nerrors = compile(locations, bc, b);
   assert(bc->globals->ncfunctions == ncfunc);
   if (nerrors > 0) {