first VM impl

Makefile

@@ -6,6 +6,13 @@ build:
 	lex scan.l
 	gcc -o bin/picrin -I./include src/main.c src/state.c src/gc.c src/pair.c src/write.c src/symbol.c src/value.c src/y.tab.c src/lex.yy.c src/eval.c src/bool.c
 
+test-vm:
+	cd src; \
+	yacc -d parse.y; \
+	lex scan.l
+	gcc -o bin/picrin -I./include src/vm.c src/state.c src/gc.c src/pair.c src/write.c src/symbol.c src/value.c src/y.tab.c src/lex.yy.c src/eval.c src/bool.c
+	bin/picrin
+
 clean:
 	rm -f src/y.tab.c src/y.tab.h src/lex.yy.c
 	rm -f bin/picrin

include/picrin.h

@@ -12,6 +12,7 @@ struct pic_env {
 };
 
 typedef struct {
+  pic_value *sp;
   struct pic_env *global_env;
 } pic_state;
 

src/state.c

@@ -20,6 +20,7 @@ pic_open()
   pic_state *pic;
 
   pic = (pic_state *)malloc(sizeof(pic_state));
+  pic->sp = (pic_value *)malloc(sizeof(pic_value) * 1024);
   pic->global_env = pic_new_empty_env();
 
   return pic;

src/vm.c

@@ -0,0 +1,81 @@
+#include <stdlib.h>
+
+#include "picrin.h"
+
+enum pic_instruction {
+  OP_PUSHI,
+  OP_ADD,
+  OP_STOP
+};
+
+struct pic_code {
+  enum pic_instruction insn;
+  union {
+    int i;
+  } u;
+};
+
+struct pic_proc {
+  union {
+    struct pic_code *code;
+  } u;
+};
+
+pic_value
+pic_run(pic_state *pic, struct pic_proc *proc, pic_value args)
+{
+  struct pic_code *pc;
+  pic_value *sp;
+
+  pc = proc->u.code;
+  sp = pic->sp;
+
+  while (1) {
+    switch (pc->insn) {
+    case OP_PUSHI: {
+      *++sp = pic_int_value(pc->u.i);
+      break;
+    }
+    case OP_ADD: {
+      pic_value a, b;
+      a = *sp--;
+      b = *sp--;
+      *++sp = pic_int_value(pic_int(a) + pic_int(b));
+      break;
+    }
+    case OP_STOP:
+      goto STOP;
+    }
+    pc++;
+  }
+
+ STOP:
+  return *sp;
+}
+
+int
+main()
+{
+  pic_state *pic;
+  struct pic_proc proc;
+  struct pic_code *code;
+  pic_value v;
+
+  pic = pic_open();
+
+  proc.u.code = code = (struct pic_code *)malloc(sizeof(struct pic_code) * 256);
+  code[0].insn = OP_PUSHI;
+  code[0].u.i = 1;
+  code[1].insn = OP_PUSHI;
+  code[1].u.i = 2;
+  code[2].insn = OP_ADD;
+  code[3].insn = OP_STOP;
+
+  v = pic_run(pic, &proc, pic_nil_value());
+
+  pic_debug(pic, v);
+
+  pic_close(pic);
+
+  return 0;
+}