refactor: assembler.h

lib/asm/asm_cmd.h

@@ -0,0 +1,27 @@
+#ifndef ASM_CMD
+#error "macro ASM_CMD was not defined"
+#endif
+
+#define _ ,
+
+ASM_CMD(NOP, 0x00, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(ADD, 0x01, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(INC, 0x02, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(SUB, 0x03, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(DEC, 0x04, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(MUL, 0x05, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(DIV, 0x06, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(PUSH,0x07, {.arg_count = 1 _ .arg_list = {{.perms = ARG_RD}}})
+
+ASM_CMD(POP, 0x08, {.arg_count = 0 _ .arg_list = {}})
+
+ASM_CMD(HALT,0x09, {.arg_count = 0 _ .arg_list = {}})
+
+#undef _

lib/asm/assembler.h

@@ -14,52 +14,83 @@
 
 #include <stddef.h>
 
+#define ASM_CMD(name, num, ...) CMD_##name=num,
+
 /**
  * @brief 
  * Byte-codes of virtual CPU instructions
  */
-enum asm_command
+enum cpu_command : char
 {
-    CMD_NOP     = 0x00,
-    CMD_ADD     = 0x01,
-    CMD_INC     = 0x02,
-    CMD_SUB     = 0x03,
-    CMD_DEC     = 0x04,
-    CMD_MUL     = 0x05,
-    CMD_DIV     = 0x06,
-    CMD_PUSH    = 0x07,
-    CMD_POP     = 0x08,
-    CMD_HALT    = 0x09
+    #include "asm_cmd.h"
 };
 
+#undef ASM_CMD
+
+const size_t ARG_MAX = 1;
+
+/**
+ * @brief 
+ * Permissions required for CPU command's formal argument
+ */
+enum arg_perms
+{
+    ARG_RD      = 01,
+    ARG_WR      = 02,
+    ARG_RDWR    = ARG_RD | ARG_WR
+};
+
+/**
+ * @brief 
+ * Description of CPU command formal argument
+ */
+struct asm_arg
+{
+    int*        val_ptr;
+    arg_perms   perms;
+};
+
+/**
+ * @brief 
+ * Inforamtion about specific command's formal
+ * arguments
+ */
+struct cmd_args
+{
+    size_t arg_count;
+    asm_arg arg_list[ARG_MAX];
+};
+
+/**
+ * @brief Wrapper for struct initializers
+ * 
+ * @param args `cmd_args` initializet
+ * @return args
+ */
+inline cmd_args get_arg(cmd_args args) { return args; }
+
 /**
  * @brief 
  * Description for virtual CPU command
  */
 struct command_description
 {
-    asm_command command;
+    cpu_command command;
     const char* name;
     size_t      arg_count;
 };
 
+#define ASM_CMD(cmd_name, num, args, ...)\
+    { .command = (cpu_command) num, .name = #cmd_name, .arg_count = get_arg(args).arg_count },
 /**
  * @brief 
  * All commands array
  */
 const command_description COMMANDS[] =
 {
-    {.command = CMD_NOP,    .name = "nop",  .arg_count = 0},
-    {.command = CMD_ADD,    .name = "add",  .arg_count = 0},
-    {.command = CMD_INC,    .name = "inc",  .arg_count = 0},
-    {.command = CMD_SUB,    .name = "sub",  .arg_count = 0},
-    {.command = CMD_DEC,    .name = "dec",  .arg_count = 0},
-    {.command = CMD_MUL,    .name = "mul",  .arg_count = 0},
-    {.command = CMD_DIV,    .name = "div",  .arg_count = 0},
-    {.command = CMD_PUSH,   .name = "push", .arg_count = 1},
-    {.command = CMD_POP,    .name = "pop",  .arg_count = 0},
-    {.command = CMD_HALT,   .name = "halt", .arg_count = 0}
+    #include "asm_cmd.h"
 };
+#undef ASM_CMD
 
 /**
  * @brief 

output/listing.txt

@@ -1,9 +1,9 @@
-1:	           push 50	7 50
-2:	           push 30	7 30
-3:	               sub	3
-4:	            push 5	7 5
-5:	            push 3	7 3
-6:	               sub	3
-7:	               div	6
-8:	               pop	8
-9:	              halt	9
+[000000] 0x0007 0x0032          | push 50
+[0x0002] 0x0007 0x001e          | push 30
+[0x0004] 0x0003                 | sub
+[0x0005] 0x0007 0x0005          | push 5
+[0x0007] 0x0007 0x0003          | push 3
+[0x0009] 0x0003                 | sub
+[0x000a] 0x0006                 | div
+[0x000b] 0x0008                 | pop
+[0x000c] 0x0009                 | halt

src/asm/asm_utils.cpp

@@ -79,15 +79,17 @@ void try_print_listing(const TextLines text_lines, const void* cmd_array)
     LOG_ASSERT_ERROR(listing != NULL, return,
         "Could not open listing file \'%s\'", listing_file);
 
-    const int *int_cmd = (const int*)cmd_array;
+    const unsigned int *int_cmd = (const unsigned int*)cmd_array;
+    size_t ip = 0;
 
     for (size_t i = 0; i < text_lines.line_count; i++)
     {
-        fprintf(listing, "%zu:\t%24s|\t%04x", i + 1, text_lines.lines[i].line, *int_cmd);
-        size_t arg_count = COMMANDS[*int_cmd].arg_count;
-        int_cmd++;
+        fprintf(listing, "[%#06zx] %#06x", ip, int_cmd[ip]);
+        size_t arg_count = COMMANDS[int_cmd[ip]].arg_count;
+        ip++;
         for (size_t j = 0; j < arg_count; j++)
-            fprintf(listing, " %04x", *(int_cmd++));
-        fputc('\n', listing);
+            fprintf(listing, " %#06x", int_cmd[ip++]);
+        fprintf(listing, "%*s %s\n", (ARG_MAX - arg_count + 1) * 7 + 4,
+                "|", text_lines.lines[i].line);
     }
 }

src/asm/asm_utils.h

@@ -55,12 +55,56 @@ const arg_tag TAGS[] =
  */
 const size_t TAG_COUNT = sizeof(TAGS)/sizeof(*TAGS);
 
+enum assembly_result
+{
+    ASM_SUCCESS     = 0,
+    ASM_SYNTAX      = -1,
+    ASM_LABEL_OVF   = -2,
+    ASM_DEFS_OVF    = -3,
+    ASM_FIXUP_OVF   = -4
+};
+
+const size_t MAX_LABEL_LEN = 32;
+struct asm_label
+{
+    char name[32];
+    ssize_t addr;
+};
+
+struct fixup
+{
+    size_t label_number;
+    size_t addr;
+};
+
+struct asm_def
+{
+    char name[MAX_LABEL_LEN];
+    int value;
+};
+
+const size_t MAX_LABELS = 64;
+const size_t MAX_FIXUPS = MAX_LABELS * 4;
+
+struct assembly_state
+{
+    padded_header   header;
+    size_t          ip;
+    int*            cmd;
+    asm_label       labels[MAX_LABELS];
+    asm_def         definitions[MAX_LABELS];
+    fixup           fixups[MAX_FIXUPS];
+    assembly_result result;
+};
+
+int assemble(TextLines* text_lines, assembly_state* state);
+
 /**
  * @brief Get the command by name
  * 
  * @param[in] str Command name
- * @param[out] n_read Number of charachters read from `str`
- * @return pointer to mathcing `command_description` upon success,
+ * @param[out] n_read Number of characters read from `str`
+ * @return pointer to matching `command_description` upon success,
  * `NULL` otheriwse
  */
 const command_description* get_description(const char* str, int* n_read);