new words

include/fh_config.h

@@ -16,4 +16,6 @@
 #define HEAP_SIZE (1024*1024)
 #define MAXLINE 65535
 
+#define CELL 4
+
 #endif //FORTH_FH_CONFIG_H

include/fh_error.h

@@ -23,6 +23,8 @@ enum fh_error {
   FH_ERR_INVALID_STATE,
   FH_ERR_INTERNAL,
   FH_ERR_UNKNOWN_WORD,
+  FH_ERR_ILLEGAL_FETCH,
+  FH_ERR_DIV_BY_ZERO,
   FH_ERR_MAX,
 };
 

include/fh_globals.h

@@ -7,6 +7,8 @@
 #ifndef FORTH_FH_GLOBALS_H
 #define FORTH_FH_GLOBALS_H
 
+#include <stdbool.h>
+
 /** Forth runtime global state */
 struct fh_global_s {
   /** Verbose logging enabled */

include/fh_mem.h

@@ -7,6 +7,14 @@
 #ifndef FORTH_FH_MEM_H
 #define FORTH_FH_MEM_H
 
+enum fh_error fh_fetch(struct fh_thread_s *fh, uint32_t addr, uint32_t *dst);
+
+enum fh_error fh_fetch_char(struct fh_thread_s *fh, uint32_t addr, char *dst);
+
+enum fh_error fh_store(struct fh_thread_s *fh, uint32_t addr, uint32_t val);
+
+enum fh_error fh_store_char(struct fh_thread_s *fh, uint32_t addr, char val);
+
 enum fh_error fh_heap_reserve(
     struct fh_thread_s *fh,
     size_t len,

include/fh_runtime.h

@@ -19,7 +19,7 @@ struct fh_instruction_s;
 struct fh_thread_s;
 
 /** Word handler typedef */
-typedef enum fh_error (*word_exec_t)(struct fh_thread_s *fh);
+typedef enum fh_error (*word_exec_t)(struct fh_thread_s *fh, const struct fh_word_s *w);
 
 /** Bytecode instruction type marker */
 enum fb_instruction_kind {
@@ -62,6 +62,7 @@ _Static_assert(sizeof(struct fh_instruction_s) % 4 == 0, "Instruction struct is
 enum fh_state {
   FH_STATE_INTERPRET = 0,
   FH_STATE_COMPILE,
+  FH_STATE_QUIT,
   FH_STATE_SHUTDOWN,
   FH_STATE_MAX,
 };
@@ -93,8 +94,11 @@ struct fh_word_s {
   /** Indicates that this instruction should always be treated as interpreted,
    * in practice this is only used for `;` */
   bool immediate;
-  /** Start address in case of user words */
-  uint32_t start;
+  /** Start address in case of user words, or param for builtins */
+  union {
+    uint32_t start;
+    uint32_t param;
+  };
 };
 
 /**
@@ -139,9 +143,8 @@ struct fh_thread_s {
   /** Forth sub-state */
   enum fh_substate substate;
 
-  /** Word currently being executed - a pointer is placed here
-   * before calling the handler */
-  struct fh_word_s *exec_word;
+  /** The numeric base register */
+  uint32_t base;
 };
 
 enum fh_error fh_add_word(const struct fh_word_s *w, struct fh_thread_s *fh);
@@ -149,10 +152,13 @@ enum fh_error fh_add_word(const struct fh_word_s *w, struct fh_thread_s *fh);
 void fh_setstate(struct fh_thread_s *fh, enum fh_state state, enum fh_substate substate);
 void fh_setsubstate(struct fh_thread_s *fh, enum fh_substate substate);
 
-enum fh_error w_user_word(struct fh_thread_s *fh);
+enum fh_error w_user_word(struct fh_thread_s *fh, const struct fh_word_s *w);
 
 /* if the return address is this, we should drop back to interactive mode */
+
+// SFR and magic addresses are "negative"
 #define MAGICADDR_INTERACTIVE 0xFFFFFFFFULL
+#define MAGICADDR_BASE 0xFFFBA5EFULL
 
 /** Get a value rounded up to multiple of word size */
 #define WORDALIGNED(var) (((var) + 3) & ~3)