#include "assembler.h"
#include <stdlib.h>
/*
gcc -c -ansi -Wall -Wextra -Wpedantic -Werror:
-- warns about trailing comma in enumerations.
-- kept because of chad coding standard.
-- unused functions for now, obviously...
clang -c -ansi -Weverything -Werror:
-- exactly same warnings as with gcc above.
splint -fcnuse +boolint +charint assembler.c:
-- we obviously ignore unused functions for now.
-- we assume bool is int, which is true.
-- we assume char is int, which is true.
-- assembler.c:167:13: Function fabs shadows outer declaration
-- ^ function from <math.h>, which we don't even use.
splint assembler.h:
-- no warnings at all.
*/
#define REGULAR_BEGIN (ADD)
#define REGULAR_END (CMP)
#define IRREGULAR_BEGIN (INC)
#define IRREGULAR_END (IDIV)
#define SPECIAL_1_BEGIN (NOP)
#define SPECIAL_1_END (HLT)
#define SPECIAL_2_BEGIN (SYSENTER)
#define SPECIAL_2_END (CPUID)
#define JUMP_IF_BEGIN (JO)
#define JUMP_IF_END (JG)
#define MOVE_IF_BEGIN (CMOVO)
#define MOVE_IF_END (CMOVG)
#define REGULAR_COUNT (REGULAR_END - REGULAR_BEGIN + 1)
#define IRREGULAR_COUNT (IRREGULAR_END - IRREGULAR_BEGIN + 1)
#define SPECIAL_1_COUNT (SPECIAL_1_END - SPECIAL_1_BEGIN + 1)
#define SPECIAL_2_COUNT (SPECIAL_2_END - SPECIAL_2_BEGIN + 1)
#define JUMP_IF_COUNT (JUMP_IF_END - JUMP_IF_BEGIN + 1)
#define MOVE_IF_COUNT (MOVE_IF_END - MOVE_IF_BEGIN + 1)
// Regulates displacement, immediate, label, variable, constant, string data.
static next * empty_from;
static next * empty_to;
static next * imbue_with;
static next * imbue_size;
// Main function.
static void place (form when,
byte data) {
/* */
token_array [token_count] = data;
token_count += (next) when;
}
static void print (form when,
size_index size,
next data) {
/* */
place ((when != 0) && (size >= D8), (byte) ((data >> 0) & 0XFF));
place ((when != 0) && (size >= D16), (byte) ((data >> 8) & 0XFF));
place ((when != 0) && (size >= D32), (byte) ((data >> 16) & 0XFF));
place ((when != 0) && (size >= D32), (byte) ((data >> 24) & 0XFF));
}
static form valid (form data) { return ((data >= 0) && (data <= 15)); }
static form lower (form data) { return ((data >= 0) && (data <= 7)); }
static form upper (form data) { return ((data >= 8) && (data <= 15)); }
// Important stuff that I need to handle later, it saves bytes!
static form far (next label) { return (1); /* DO NOT CHANGE YET! */ }
static form near (next label) { return (0); /* DO NOT CHANGE YET! */ }
static void build_short_prefix (form when) {
place (when, 0X66);
}
// 40-4D!0X02
static void build_long_prefix (form use_big_registers,
form use_new_destination,
form use_new_source) {
/* */
place (use_big_registers || use_new_destination || use_new_source,
(byte) (0X40
+ 0X01 * use_new_destination
+ 0X04 * use_new_source
+ 0X08 * use_big_registers));
}
// C0-FF
static void build_register_direction (form when,
next destination,
next source) {
/* */
place (when, (byte) (0XC0
+ 0X01 * (destination & 0X07)
+ 0X08 * (source & 0X07)));
}
// 05-3D
static void build_register_redirection (form when,
next direction) {
/* */
place (when, (byte) (0X05
+ 0X08 * (direction & 0X07)));
}
// 80/81
static void build_constant (form when,
size_index size) {
/* */
place (when, (byte) (0X80
+ 0X01 * (size != D8)));
}
// REGULAR_BEGIN-REGULAR_END D8-D64 REG/MEM R0-R15/MEM -||-/IMM -||-/IMM
static void build_regular (operation_index operation,
size_index size,
type_index to,
next destination,
type_index from,
next source) {
/* */
build_short_prefix (size == D16);
build_long_prefix (size == D64,
(to == REG) && (upper ((form) destination)),
(from == REG) && (upper ((form) source)));
build_constant (from == IMM, size);
place (1, (byte) (0X08 * (operation - REGULAR_BEGIN)
+ (destination & 0X07) * ((to == REG) && (from == IMM))
+ 0X01 * (size != D8)
+ 0X02 * ((from == MEM) && (to == REG))
+ 0X04 * ((from == IMM) && (to == MEM))
+ 0XC0 * ((from == IMM) && (to == REG))));
build_register_direction ((to == REG) && (from == REG),
destination, source);
build_register_redirection ((to == REG) && (from == MEM), destination);
build_register_redirection ((to == MEM) && (from == REG), source);
print ((to == REG) && (from == MEM), D32, (next) ~0);
print ((to == REG) && (from == IMM), size, source);
print ((to == MEM) && (from == REG), D32, (next) ~0);
print ((to == MEM) && (from == IMM), D32, (next) ~0);
print ((to == MEM) && (from == IMM), size, source);
}
// IRREGULAR_BEGIN-IRREGULAR_END D8-D64 REG/MEM R0-R15/MEM
static void build_irregular (operation_index operation,
size_index size,
type_index to,
next destination) {
/* */
build_short_prefix (size == D16);
build_long_prefix (size == D64,
(to == REG) && (upper ((form) destination)), 0);
place (1, (byte) (0XF6
+ 0X08 * ((operation == INC) || (operation == DEC))
+ 0X01 * (size != D8)));
place (to == REG, (byte) (0XC0
+ 0X08 * (operation - IRREGULAR_BEGIN))
+ 0X01 * (destination & 0X07));
place (to == MEM, (byte) (0X05
+ 0X08 * (operation - IRREGULAR_BEGIN)));
}
// SPECIAL_1_BEGIN-SPECIAL_1_END
static void build_special_1 (operation_index operation) {
const byte data [1 * SPECIAL_1_COUNT] = {
0X90, 0XC3, 0XCB, 0XC9, 0XF0, 0XF4
};
place (1, data [operation - SPECIAL_1_BEGIN]);
}
// SPECIAL_2_BEGIN-SPECIAL_2_END
static void build_special_2 (operation_index operation) {
const byte data [2 * SPECIAL_2_COUNT] = {
0X0F, 0X0F, 0X0F, 0X0F, 0XF3, 0X0F,
0X34, 0X35, 0X05, 0X07, 0X90, 0XA2
};
place (1, data [operation - SPECIAL_2_BEGIN]);
place (1, data [operation - SPECIAL_2_BEGIN + SPECIAL_2_COUNT]);
}
// JUMP_IF_BEGIN-JUMP_IF_END D8/32 IMM8/32
static void build_jump_if (operation_index operation,
size_index size,
next location) {
/* */
(void) size; /* HIGHLY DEPENDS FOR FAR AND NEAR JUMPS! */
place (far (location), 0X0F); /* EVERYTHING IS FAR JUMP! */
place (far (location), (byte) (0X80 + operation - JUMP_IF_BEGIN));
place (near (location), (byte) (0X70 + operation - JUMP_IF_BEGIN));
//~displacement (4, 0X12345678);
}
// MOVE_IF_BEGIN-MOVE_IF_END D16-D64 REG R0-R15 -||-/MEM -||-/MEM
static void build_move_if (operation_index operation,
size_index size,
type_index to,
next destination,
type_index from,
next source) {
/* */
build_short_prefix (size == D16);
build_long_prefix (size == D64,
(to == REG) && (upper ((form) destination)),
(from == REG) && (upper ((form) source)));
place (1, 0X0F);
place (1, (byte) (0X40 + operation - MOVE_IF_BEGIN));
build_register_direction ((to == REG) && (from == REG),
destination, source);
build_register_redirection ((to == REG) && (from == MEM), destination);
//~displacement (4, 0X12345678); // Not implemented at this point!
}
// SPECIAL!
static void build_jump (size_index size,
type_index to,
next destination) {
/* */
place ((to == REG) && upper ((form) destination), (byte) 0X41);
place (to == REL, (byte) (0XE9 + 0X02 * (size == D8)));
place (to == REG, (byte) 0XFF);
place (to == REG, (byte) (0XE0 + 0X01 * (destination & 0X07)));
place (to == MEM, (byte) 0XFF);
place (to == MEM, (byte) 0X25);
//~displacement (to == MEM, 4, 0X12345678); // Keep when in mind!
}
// VERY FUCKING SPECIAL!
static void build_move (size_index size,
type_index to,
next destination,
type_index from,
next source) {
/* */
build_short_prefix (size == D16);
build_long_prefix (size == D64,
(to == REG) && (upper ((form) destination)),
(from == REG) && (upper ((form) source)));
place ((to == REG) && (from == REG), (byte) (0X88 + (size != D8)));
place ((to == REG) && (from == MEM), (byte) (0X8A + (size != D8)));
place ((to == MEM) && (from == REG), (byte) (0X88 + (size != D8)));
build_register_redirection ((to == REG) && (from == MEM), destination);
build_register_redirection ((to == MEM) && (from == REG), source);
place ((to == REG) && (from == IMM), (byte) (0XB0
+ 0X08 * (size != D8)
+ 0X01 * (destination & 0X07)));
place ((to == MEM) && (from == IMM), (byte) (0XC6 + (size != D8)));
place ((to == MEM) && (from == IMM), (byte) (0X05));
print ((to == REG) && (from == MEM), D32, (next) ~0);
print ((to == REG) && (from == IMM), size, source);
print ((to == MEM) && (from == REG), D32, (next) ~0);
print ((to == MEM) && (from == IMM), D32, (next) ~0);
print ((to == MEM) && (from == IMM), size, source);
}
next token_count;
byte * token_array;
void assemble (next count,
next * array) {
/* */
next index;
for (index = 0; index < count; ++index) {
if ((array [index] >= REGULAR_BEGIN)
&& (array [index] <= REGULAR_END)) {
build_regular (array [index + 0], array [index + 1],
array [index + 2], array [index + 3],
array [index + 4], array [index + 5]);
index += 5;
} else if ((array [index] >= IRREGULAR_BEGIN)
&& (array [index] <= IRREGULAR_END)) {
build_irregular (array [index + 0], array [index + 1],
array [index + 2], array [index + 3]);
index += 3;
} else if ((array [index] >= SPECIAL_1_BEGIN)
&& (array [index] <= SPECIAL_1_END)) {
build_special_1 (array [index + 0]);
index += 0;
} else if ((array [index] >= SPECIAL_2_BEGIN)
&& (array [index] <= SPECIAL_2_END)) {
build_special_2 (array [index + 0]);
index += 0;
} else if ((array [index] >= JUMP_IF_BEGIN)
&& (array [index] <= JUMP_IF_END)) {
build_jump_if (array [index + 0], array [index + 1],
array [index + 2]);
index += 2;
} else if ((array [index] >= MOVE_IF_BEGIN)
&& (array [index] <= MOVE_IF_END)) {
build_move_if (array [index + 0], array [index + 1],
array [index + 2], array [index + 3],
array [index + 4], array [index + 5]);
index += 5;
} else if (array [index] == JMP) {
build_jump (array [index + 1], array [index + 2],
array [index + 3]);
index += 3;
} else if (array [index] == MOV) {
build_move (array [index + 1], array [index + 2],
array [index + 3], array [index + 4],
array [index + 5]);
index += 5;
} else {
exit (EXIT_FAILURE); // For debugging only!
}
}
}