diff options
Diffstat (limited to 'twasm/asm/main.asm')
| -rw-r--r-- | twasm/asm/main.asm | 343 |
1 files changed, 278 insertions, 65 deletions
diff --git a/twasm/asm/main.asm b/twasm/asm/main.asm index 0383da2..156bf02 100644 --- a/twasm/asm/main.asm +++ b/twasm/asm/main.asm @@ -2,16 +2,21 @@ LOAD_ADDR equ 0x00010000 ; address this program is loaded at +STACK_ADDR equ 0x00030000 ; address to put the 64-bit stack at + +AWAITING_LABEL_TABLE_ADDR equ 0x00030000 ; address to store pending labels at +AWAITING_LABEL_TABLE_SIZE equ 0x00010000 +LABEL_TABLE_ADDR equ 0x00040000 ; address to store labels at +LABEL_TABLE_SIZE equ 0x00010000 + TEST_ARENA_ADDR equ 0x00050000 ; address to run tests at -TEST_ARENA_SIZE equ 0x1000 ; maximum size tests can use +TEST_ARENA_SIZE equ 0x00010000 ; maximum size tests can use TOKEN_TABLE_ADDR equ 0x00060000 ; address the token table is loaded at -TOKEN_TABLE_SIZE equ 0x1000 ; max length of table +TOKEN_TABLE_SIZE equ 0x00010000 ; max length of table OUTPUT_ADDR equ 0x00070000 ; address of outputed binary -OUTPUT_SIZE equ 0x1000 ; max length of outputed binary - -STACK_ADDR equ 0x00060000 ; address to put the 64-bit stack at +OUTPUT_SIZE equ 0x00010000 ; max length of outputed binary UNRECOGNISED_TOKEN_ID equ 0xFFFF ; id of an unrecognised token UNRECOGNISED_ID_TYPE equ 0x0F ; type of an unrecognised id @@ -27,6 +32,7 @@ E_WHITESPACE equ 1 << 2 E_COMMA equ 1 << 3 E_OPERATOR equ 1 << 4 E_OPERAND equ 1 << 5 +E_LABEL equ 1 << 6 [bits 64] [org LOAD_ADDR] @@ -43,6 +49,7 @@ start: call run_tests call clear_token_table + call clear_label_tables mov rdi, program ; -> program mov rsi, [program.size] ; = size of program @@ -98,6 +105,7 @@ assemble: cmp al, 0x1 ; check if next tte is an operator je .operator ; if so, handle + jmp .unexpected_token ; otherwise, fail .operator: ; if next tte's type is an operator: @@ -120,7 +128,6 @@ assemble: je .operator_2 ; if so, handle case of two operands jmp .unexpected_token - .operator_0: mov rsi, .msg_operator_0 call print.debug @@ -133,7 +140,6 @@ assemble: call .write_byte jmp .loop_next_token - .operator_1: mov rsi, .msg_operator_1 call print.debug @@ -167,12 +173,10 @@ assemble: je .operator_1_register jmp .unexpected_token - .operator_1_memory: mov rsi, .msg_operator_1_memory call print.debug jmp .unsupported_memory_access - .operator_1_register: mov rsi, .msg_operator_1_register call print.debug @@ -213,7 +217,6 @@ assemble: call .write_byte jmp .loop_next_token - .operator_2: mov rsi, .msg_operator_2 call print.debug @@ -240,7 +243,6 @@ assemble: je .operator_2_register jmp .unexpected_token - .operator_2_memory: mov rsi, .msg_operator_2_memory call print.debug @@ -319,7 +321,6 @@ assemble: cmp al, 11b ; 64 bit je .operator_2_memory_register_64 - .operator_2_memory_register_16: mov al, 0x66 call .push_byte @@ -337,7 +338,6 @@ assemble: call .write_byte jmp .loop_next_token - .operator_2_register: mov rsi, .msg_operator_2_register call print.debug @@ -398,7 +398,6 @@ assemble: je .operator_2_register_register ; if so, handle jmp .unexpected_token - .operator_2_register_memory: push rsi mov rsi, .msg_operator_2_register_memory @@ -441,7 +440,6 @@ assemble: call .write_byte jmp .loop_next_token - .operator_2_register_register: push rsi mov rsi, .msg_operator_2_register_register @@ -543,7 +541,6 @@ assemble: jmp .operator_2_register_register_continue .operator_2_register_register_continue: - push rsi mov esi, edi ; si = reg; src tte pop rdi ; di = r/m; dst tte @@ -658,7 +655,7 @@ assemble: call .output_byte mov byte [ecx], 0x00 jmp .flush_write_buffer_loop - .flush_write_buffer_break + .flush_write_buffer_break: mov dword [.buffer_pointer], .buffer pop rax pop rcx @@ -680,6 +677,7 @@ assemble: .msg_operator_2_register db "operator_2_register", 0x0A, 0x00 .msg_operator_2_register_memory db "operator_2_register_memory", 0x0A, 0x00 .msg_operator_2_register_register db "operator_2_register_register", 0x0A, 0x00 + .msg_potential_label db "potential_label", 0x0A, 0x00 ; ------------------------------------------------------------------------------ ; get_tte_type @@ -956,9 +954,11 @@ tokenise: pop rsi ; rsi -> last byte of program jnz .skip_byte_whitespace - test byte [.expecting], E_OPERATOR ; check if an operator is expected + test byte [.expecting], E_LABEL ; check if a label is expected + jnz .label ; if so, handle it + test byte [.expecting], E_OPERATOR ; else, check if an operator is expected jnz .operator ; if so, handle it - jmp .operand ; otherwise, handle as an operand + jmp .operand ; else, handle as an operand .comment: push rsi @@ -1021,11 +1021,72 @@ tokenise: test byte [.expecting], E_NEWLINE ; make sure a newline was expected jz .unexpected_newline ; if not, error - mov byte [.expecting], E_COMMENT | E_NEWLINE | E_WHITESPACE | E_OPERATOR + mov byte [.expecting], E_COMMENT | E_NEWLINE | E_WHITESPACE | E_OPERATOR | E_LABEL inc rdi jmp .loop + .label: + push rax + xor eax, eax ; rax = number of bytes in label + .label_loop: + mov dl, [rdi + rax] ; next byte + cmp dl, ":" + je .label_break + cmp dl, " " + je .label_not_found + cmp dl, 0x0A + je .label_not_found + cmp dl, 0x00 + je .label_not_found + cmp dl, ";" + je .label_not_found + inc eax ; inc byte counter + cmp rdi, rsi + jge .break + jmp .label_loop + .label_break: + push rsi + mov rsi, .found + call print.debug + mov rsi, .msg_label + call print + pop rsi ; rsi -> last byte of program + + push rax + push rdi + push rsi + + mov rsi, rdi ; rsi -> start of string + mov rdi, rax ; rdi = size of string + call djb2 + ; rax = hash + mov rdi, rax ; rdi = hash + call add_label_hash + ; rax = index on label table + mov cx, ax + and cx, 0x0FFF + or cx, 0x3000 + + pop rsi ; rsi -> last byte of program + pop rdi ; rdi -> current byte of program + pop rax ; rax = number of bytes in label + + add rdi, rax ; move on to next byte + inc rdi ; move past the colon + + pop rax ; rax = number of tokens processed + + mov [TOKEN_TABLE_ADDR + rax * 2], cx + inc rax ; the next token + + mov byte [.expecting], E_COMMENT | E_NEWLINE | E_WHITESPACE + jmp .loop + .label_not_found: + pop rax ; rax = number of tokens processed + mov byte [.expecting], E_COMMENT | E_NEWLINE | E_WHITESPACE | E_OPERATOR + jmp .loop + .operator: ; debug message push rsi @@ -1038,7 +1099,6 @@ tokenise: mov rcx, rax ; rcx = number of tokens processed xor eax, eax ; eax = number of bytes in operator mov [.pending_operator], eax ; zero pending operator - .operator_loop: ; TODO give this its own error @@ -1063,7 +1123,6 @@ tokenise: cmp rdi, rsi jge .break jmp .operator_loop ; and loop - .operator_break: ; rax already pushed from .operator push rdi @@ -1097,7 +1156,6 @@ tokenise: push rax push rdi xor eax, eax ; rax = length of operand - .operand_loop: mov dl, [rdi] @@ -1113,7 +1171,6 @@ tokenise: inc rax ; inc length counter inc rdi ; inc byte pointer jmp .operand_loop - .operand_break: pop rdi ; rdi -> first byte of operand push rdi @@ -1121,9 +1178,11 @@ tokenise: mov rsi, rax ; rsi = length of operand in bytes mov cx, ax ; cx = length counter for safe keeping + push rcx call evaluate_operand ; dl = return code ; rax = binary data + pop rcx pop rsi pop rdi ; rdi = first byte of operand add di, cx ; rdi = last byte of operand @@ -1131,31 +1190,48 @@ tokenise: pop rax ; rax = number of tokens processed ; operand is some reg - ; cx = token ID cmp dl, 0x00 + ; cx = token ID je .operand_register ; operand is some [reg] - ; cx = token ID cmp dl, 0x10 + ; cx = token ID je .operand_addr_register - jmp .unexpected_operand + ; operand is some constant + cmp dl, 0x20 + ; rcx = constant value + je .operand_constant + + ; operand is some label + cmp dl, 0x30 + ; rcx = index of label in LT + je .operand_label - ; cx = token ID + jmp .unexpected_operand .operand_register: mov [TOKEN_TABLE_ADDR + rax * 2], cx inc rax ; another token processed jmp .operand_break_continue - - ; cx = token ID .operand_addr_register: mov word [TOKEN_TABLE_ADDR + rax * 2], 0x1000 inc rax ; 0x1000: addr reg token, next token is the register mov [TOKEN_TABLE_ADDR + rax * 2], cx inc rax ; the register as returned by evaluate_operand jmp .operand_break_continue - + .operand_constant: + mov word [TOKEN_TABLE_ADDR + rax * 2], 0x2000 + inc rax ; another token processed + mov [TOKEN_TABLE_ADDR + rax * 2], rcx + add rax, 4 + jmp .operand_break_continue + .operand_label: + and cx, 0x0FFF + or cx, 0x3000 + mov [TOKEN_TABLE_ADDR + rax * 2], cx + inc rax + jmp .operand_break_continue .operand_break_continue: mov byte [.expecting], E_COMMENT | E_NEWLINE | E_WHITESPACE | E_COMMA jmp .loop @@ -1164,8 +1240,7 @@ tokenise: ret ; state - - .expecting db E_COMMENT | E_NEWLINE | E_WHITESPACE | E_OPERATOR + .expecting db E_COMMENT | E_NEWLINE | E_WHITESPACE | E_OPERATOR | E_LABEL .unexpected_whitespace: mov rsi, .err_unexpected @@ -1209,6 +1284,7 @@ tokenise: .msg_comment db "comment.", 0x0A, 0x00 .msg_newline db "newline.", 0x0A, 0x00 .msg_comma db "comma.", 0x0A, 0x00 + .msg_label db "label.", 0x0A, 0x00 .msg_operator db "operator.", 0x0A, 0x00 .msg_operand db "operand.", 0x0A, 0x00 .pending_operator dd 0 ; the operator token that is pending processing @@ -1220,10 +1296,12 @@ tokenise: ; takes the location and length of an operand and evaluates it into binary data ; and a return code to interpret the binary data. ; -; | code | rsi contents | notes | +; | code | rax contents | notes | ; |------|----------------------|-------| ; | 0x00 | token ID of register | reg | ; | 0x10 | token ID of register | [reg] | +; | 0x20 | constant value | const | +; | 0x30 | index of label in LT | label | ; | 0xFF | - | error | ; ; parameters: @@ -1239,6 +1317,7 @@ evaluate_operand: push rdi ; rdi -> start of operand ; rsi = size of operand call trim_trailing_whitespace + ; rax = new size of operand pop rdi ; rdi -> first byte of operand mov rsi, rax ; rsi = size of operand w/o trailing whitespace @@ -1249,7 +1328,7 @@ evaluate_operand: cmp byte [rdi], '[' ; case: memory addressing je .address - jmp .register ; otherwise: register + jmp .register ; otherwise: register (or constant, or label) .address: cmp byte [rdi + rsi - 1], ']' ; check if address is closed correctly @@ -1262,12 +1341,13 @@ evaluate_operand: cmp dl, 0x10 ; make sure return code isn't another memory reference je .unrecognised ; if it is, fail - or dl, 0x10 ; flip bit for address return + shr edx, 4 + or dl, 0x10 ; address return ret .register: cmp rsi, 4 - jg .unrecognised + jg .constant ; not a register: too long. Maybe constant? push rdi mov edi, [rdi] ; edi = register to be searched @@ -1288,18 +1368,47 @@ evaluate_operand: .register3: and edi, 0xFFFFFF .register4: - call identify_register ; ax = register's token ID or UNRECOGNISED_TOKEN_ID - pop rdi + pop rdi ; rdi -> first byte of operand - cmp ax, UNRECOGNISED_TOKEN_ID - je .unrecognised + cmp ax, UNRECOGNISED_TOKEN_ID ; if not a register, constant? + je .constant mov dl, 0x00 ret + .constant: + push rdi + push rsi + ; rdi -> first byte of constant + ; rsi = size of constant in bytes + call evaluate_constant + ; dl = type of constant + ; rax = hex value of constant + pop rdi ; rdi = size of label in bytes + pop rsi ; rsi -> first byte of label + + cmp dl, 0xFF + je .label + + ; rax = hex value of constant + mov dl, 0x20 + ret + + .label: + ; rdi = size of label in bytes + ; rsi -> first byte of label + call djb2 + ; rax = hash + mov rdi, rax ; rdi = hash + call add_label_hash + ; rax = index in LT of label + mov dl, 0x30 + ret + .unrecognised: + xor eax, eax mov dl, 0xFF ret @@ -1353,6 +1462,7 @@ evaluate_constant: je .chr pop rcx + push rcx ; waste value; .unrecognise expects something on the stack jmp .unrecognised .numeric: @@ -1396,12 +1506,10 @@ evaluate_constant: cmp dl, 9 ; if !digit: jg .hex_alpha ; letter jmp .hex_continue ; else loop - .hex_alpha: sub dl, 7 ; map [('A'-'0')..('F'-'0')] to [0xA..0xF] cmp dl, 0xF ; if not in the range [0xA..0xF] jg .unrecognised ; then unrecognised - .hex_continue: and dl, 0x0F ; mask or al, dl ; and add newest nibble @@ -1471,14 +1579,12 @@ evaluate_constant: inc rdi jmp .chr - .chr_break: cmp rcx, 1 ; for each [1..rcx] jle .chr_break_for_good rol rax, 8 ; roll left to make up for the roll right earlier dec rcx jmp .chr_break - .chr_break_for_good: mov dl, [rdi] ; make sure the chr is closed cmp dl, '"' @@ -1492,8 +1598,9 @@ evaluate_constant: .unrecognised: pop rdx - mov rdx, 0xFF ; unrecognised type + mov edx, 0xFF ; unrecognised type ret + .msg db "evaluate_constant", 0x0A, 0x00 ; ------------------------------------------------------------------------------ ; identify_register @@ -1751,6 +1858,38 @@ trim_trailing_whitespace: ret ; ------------------------------------------------------------------------------ +; add_label_hash +; +; description: +; adds a label hash to the label table, or just finds it if already present +; +; parameters +; rdi = 64-bit hash to be added +; +; returned +; rax = index in label table +; ------------------------------------------------------------------------------ + +add_label_hash: + xor eax, eax + .loop: + cmp rax, LABEL_TABLE_SIZE + jge .break + mov rcx, [LABEL_TABLE_ADDR + rax] + ; TODO bug if there's an empty slot before the entry, it won't be found + cmp rcx, 0 ; empty slot + je .break + cmp rcx, rdi ; already present + je .break + add rax, 16 + jmp .loop + .break: + mov [LABEL_TABLE_ADDR + rax], rdi + shr rax, 4 ; rax / 16 + ; rax = index + ret + +; ------------------------------------------------------------------------------ ; clear_token_table ; ; description: @@ -1765,6 +1904,26 @@ clear_token_table: ret ; ------------------------------------------------------------------------------ +; clear_label_tables +; +; description: +; clears the label table as specified by LABEL_TABLE_SIZE and LABEL_TABLE_ADDR +; and the awaiting label table as specified by AWAITING_LABEL_TABLE_SIZE and +; AWAITING_LABEL_TABLE_ADDR +; ------------------------------------------------------------------------------ + +clear_label_tables: + xor eax, eax ; value to write + mov ecx, LABEL_TABLE_SIZE / 4 ; number of double words + mov edi, LABEL_TABLE_ADDR ; address to start + rep stosd + xor eax, eax ; value to write + mov ecx, AWAITING_LABEL_TABLE_SIZE / 4 ; number of double words + mov edi, AWAITING_LABEL_TABLE_ADDR ; address to start + rep stosd + ret + +; ------------------------------------------------------------------------------ ; clear_test_arena ; ; description: @@ -1772,9 +1931,9 @@ clear_token_table: ; ------------------------------------------------------------------------------ clear_test_arena: - xor eax, eax ; value to write - mov ecx, TOKEN_TABLE_SIZE / 4 ; number of double words - mov edi, TOKEN_TABLE_ADDR ; address to start + xor eax, eax ; value to write + mov ecx, TEST_ARENA_SIZE / 4 ; number of double words + mov edi, TEST_ARENA_ADDR ; address to start rep stosd ret @@ -2341,22 +2500,76 @@ whitespace_2 db " ", 0x0D ; test program program: - db "xor eax, eax", 0x0A - db "mov rax, rax", 0x0A - db "mov rax, rbx", 0x0A - db "mov eax, ebx", 0x0A - db "mov ax, bx", 0x0A - db "inc rax ; inline comment", 0x0A - db "dec rax", 0x0A - db "; one line comment", 0x0A - db "mov rdx, [rax]", 0x0A - db "mov [rax], rdx", 0x0A - db "mov [rcx], rbx", 0x0A - db "mov rcx, [rbx]", 0x0A - db "mov rcx, [ebx]", 0x0A - db "mov ecx, [ebx]", 0x0A - db "mov cx, [ebx]", 0x0A - db "hlt", 0x0A + db "print:", 0x0A + db " push rdx", 0x0A + db " push rax", 0x0A + db " push rsi", 0x0A + db "", 0x0A + db " mov edx, 0x3F8", 0x0A + db " .loop:", 0x0A + db " mov al, [rsi]", 0x0A + db " cmp al, 0x00", 0x0A + db " je .done", 0x0A + db " out dx, al", 0x0A + db " inc rsi", 0x0A + db " jmp .loop", 0x0A + db " .done:", 0x0A + db " pop rsi", 0x0A + db " pop rax", 0x0A + db " pop rdx", 0x0A + db " ret", 0x0A + db " .debug:", 0x0A + db " push rsi", 0x0A + db " mov rsi, .debug_msg", 0x0A + db " call print", 0x0A + db " pop rsi", 0x0A + db " jmp print ; tail call", 0x0A + db " .error:", 0x0A + db " push rsi", 0x0A + db " mov rsi, .error_msg", 0x0A + db " call print", 0x0A + db " pop rsi", 0x0A + db " jmp print ; tail call", 0x0A + db " .test:", 0x0A + db " push rsi", 0x0A + db " mov rsi, .test_msg", 0x0A + db " call print", 0x0A + db " pop rsi", 0x0A + db " jmp print ; tail call", 0x0A + db " .warn:", 0x0A + db " push rsi", 0x0A + db " mov rsi, .warn_msg", 0x0A + db " call print", 0x0A + db " pop rsi", 0x0A + db " jmp print ; tail call", 0x0A + db " .debug_msg:", 0x0A + db " db 0x1B", 0x0A + db ' db "[36m"', 0x0A + db ' db "[DEBUG]: "', 0x0A + db " db 0x1B", 0x0A + db ' db "[0m"', 0x0A + db " db 0x00", 0x0A + db " .error_msg:", 0x0A + db " db 0x1B", 0x0A + db ' db "[1;31m"', 0x0A + db ' db "[ERROR]: "', 0x0A + db " db 0x1B", 0x0A + db ' db "[0m"', 0x0A + db " db 0x00", 0x0A + db " .test_msg:", 0x0A + db " db 0x1B", 0x0A + db ' db "[1;33m"', 0x0A + db ' db "[TEST]: "', 0x0A + db " db 0x1B", 0x0A + db ' db "[0m"', 0x0A + db " db 0x00", 0x0A + db " .warn_msg:", 0x0A + db " db 0x1B", 0x0A + db ' db "[1;35m"', 0x0A + db ' db "[WARN]: "', 0x0A + db " db 0x1B", 0x0A + db ' db "[0m"', 0x0A + db " db 0x00", 0x0A .size dq $ - program msg_end db "end of the binary ->|", 0x0A, 0x00 |