Free Hero Mesh

#if 0
gcc ${CFLAGS:--s -O2} -c -fwrapv exec.c `sdl-config --cflags`
exit
#endif

#include "SDL.h"
#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>

static int vstackptr;
static const char*traceprefix;

#define Throw(x) (my_error=(x),longjmp(my_env,1))
#define StackReq(x,y) do{ if(vstackptr<(x)) Throw("Stack underflow"); if(vstackptr-(x)+(y)>=VSTACKSIZE) Throw("Stack overflow"); }while(0)
#define Push(x) (vstack[vstackptr++]=(x))
#define Pop() (vstack[--vstackptr])

static Value send_message(Uint32 from,Uint32 to,Uint16 msg,Value arg1,Value arg2,Value arg3);
static Uint32 broadcast(Uint32 from,int c,Uint16 msg,Value arg1,Value arg2,Value arg3,int s);

void pfunlink(Uint32 n) {
  Object*o=objects[n];
  if(o->down==VOIDLINK) playfield[o->x+o->y*64-65]=o->up;
  else objects[o->down]->up=o->up;
  if(o->up!=VOIDLINK) objects[o->up]->down=o->down;
  o->down=o->up=VOIDLINK;

    o=objects[t0.u];
    printf(" [$%s %d %d]",classes[o->class]->name,o->x,o->y);
  }
  o=objects[obj];
  printf(" : %u %u [$%s %d %d]",o->generation,obj,classes[o->class]->name,o->x,o->y);
  printf(" : %u %u : %u %u\n",t1.t,t1.u,t2.t,t2.u);
}

static inline Value v_broadcast(Uint32 from,Value c,Value msg,Value arg1,Value arg2,Value arg3,int s) {
  if(msg.t!=TY_MESSAGE) Throw("Type mismatch");
  if(c.t!=TY_CLASS && (c.t!=TY_NUMBER || c.u)) Throw("Type mismatch");
  return NVALUE(broadcast(from,c.u,msg.u,arg1,arg2,arg3,s));
}

// Here is where the execution of a Free Hero Mesh bytecode subroutine is executed.
#define NoIgnore() do{ changed=1; }while(0)
#define GetVariableOf(a,b) (i=v_object(Pop()),i==VOIDLINK?NVALUE(0):b(objects[i]->a))
static void execute_program(Uint16*code,int ptr,Uint32 obj) {
  Uint32 i;
  Object*o=objects[obj];
  Value t1,t2;
  static Value t3,t4,t5;
  if(StackProtection()) Throw("Call stack overflow");
  for(;;) switch(code[ptr++]) {
    case 0x0000 ... 0x00FF: StackReq(0,1); Push(NVALUE(code[ptr-1])); break;
    case 0x0100 ... 0x01FF: StackReq(0,1); Push(NVALUE(code[ptr-1]-0x200)); break;
    case 0x0200 ... 0x02FF: StackReq(0,1); Push(MVALUE(code[ptr-1]&255)); break;
    case 0x0300 ... 0x03FF: StackReq(0,1); Push(UVALUE(code[ptr-1]&255,TY_SOUND)); break;
    case 0x0400 ... 0x04FF: StackReq(0,1); Push(UVALUE(code[ptr-1]&255,TY_USOUND)); break;
    case 0x2000 ... 0x27FF: StackReq(0,1); Push(o->uservars[code[ptr-1]&0x7FF]); break;
    case 0x2800 ... 0x28FF: StackReq(0,1); Push(globals[code[ptr-1]&0x7FF]); break;
    case 0x3000 ... 0x37FF: NoIgnore(); StackReq(1,0); o->uservars[code[ptr-1]&0x7FF]=Pop(); break;
    case 0x3800 ... 0x38FF: NoIgnore(); StackReq(1,0); Push(globals[code[ptr-1]&0x7FF]); break;
    case 0x4000 ... 0x7FFF: StackReq(0,1); Push(CVALUE(code[ptr-1]-0x4000)); break;
    case 0x87E8 ... 0x87FF: StackReq(0,1); Push(NVALUE(1UL<<(code[ptr-1]&31))); break;
    case 0xC000 ... 0xFFFF: StackReq(0,1); Push(MVALUE((code[ptr-1]&0x3FFF)+256)); break;
    case OP_BROADCAST: StackReq(4,1); t4=Pop(); t3=Pop(); t2=Pop(); t1=Pop(); Push(v_broadcast(obj,t1,t2,t3,t4,NVALUE(0),0)); break;
    case OP_BROADCAST_D: StackReq(4,0); t4=Pop(); t3=Pop(); t2=Pop(); t1=Pop(); v_broadcast(obj,t1,t2,t3,t4,NVALUE(0),0); break;
    case OP_BROADCASTCLASS: StackReq(3,1); t4=Pop(); t3=Pop(); t2=Pop(); Push(v_broadcast(obj,CVALUE(code[ptr++]),t2,t3,t4,NVALUE(0),0)); break;
    case OP_BROADCASTEX: StackReq(5,1); t5=Pop(); t4=Pop(); t3=Pop(); t2=Pop(); t1=Pop(); Push(v_broadcast(obj,t1,t2,t3,t4,t5,0)); break;
    case OP_BROADCASTEX_D: StackReq(5,0); t5=Pop(); t4=Pop(); t3=Pop(); t2=Pop(); t1=Pop(); v_broadcast(obj,t1,t2,t3,t4,t5,0); break;
    case OP_BROADCASTSUM: StackReq(4,1); t4=Pop(); t3=Pop(); t2=Pop(); t1=Pop(); Push(v_broadcast(obj,t1,t2,t3,t4,NVALUE(0),1)); break;
    case OP_BROADCASTSUMEX: StackReq(5,1); t5=Pop(); t4=Pop(); t3=Pop(); t2=Pop(); t1=Pop(); Push(v_broadcast(obj,t1,t2,t3,t4,t5,1)); break;
    case OP_CALLSUB: execute_program(code,code[ptr++],obj); break;
    case OP_CLASS: StackReq(0,1); Push(CVALUE(o->class)); break;
    case OP_CLASS_C: StackReq(1,1); Push(GetVariableOf(class,CVALUE)); break;
    case OP_DROP: StackReq(1,0); Pop(); break;
    case OP_DROP_D: StackReq(2,0); Pop(); Pop(); break;
    case OP_DUP: StackReq(1,2); t1=Pop(); Push(t1); Push(t1); break;
    case OP_GOTO: ptr=code[ptr]; break;

  if(!traceprefix) {
    optionquery[1]=Q_tracePrefix;
    traceprefix=xrm_get_resource(resourcedb,optionquery,optionquery,2);
    if(!traceprefix) traceprefix="";
  }
  if(msgvars.msg<256) s=standard_message_names[msgvars.msg]; else s=messages[msgvars.msg-256];
  o=msgvars.from==VOIDLINK?0:objects[msgvars.from];
  printf("%s%d : %s%s : %d : %u %u",traceprefix,move_number,msgvars.msg<256?"":"#",s,vstackptr,o?o->generation:0,o?msgvars.from:0);
  if(o) printf(" [$%s %d %d]",classes[o->class]->name,o->x,o->y);
  o=objects[obj];
  printf(" : %u %u [$%s %d %d]",o->generation,obj,classes[o->class]->name,o->x,o->y);
  printf(" : %u %u : %u %u : %u %u\n",msgvars.arg1.t,msgvars.arg1.u,msgvars.arg2.t,msgvars.arg2.u,msgvars.arg3.t,msgvars.arg3.u);
}

static Value send_message(Uint32 from,Uint32 to,Uint16 msg,Value arg1,Value arg2,Value arg3) {