added io

build/test_read_stdin.asm

@@ -0,0 +1,614 @@
+section .text
+%define DSTK_BYTES 65536
+%define RSTK_BYTES 65536
+%define PRINT_BUF_BYTES 128
+global _start
+_start:
+    ; initialize data/return stack pointers
+    lea r12, [rel dstack_top]
+    mov r15, r12
+    lea r13, [rel rstack_top]
+    call word_main
+    mov rax, 0
+    cmp r12, r15
+    je .no_exit_value
+    mov rax, [r12]
+    add r12, 8
+.no_exit_value:
+    mov rdi, rax
+    mov rax, 60
+    syscall
+word_c_40:
+	mov rax, [r12]
+	movzx rax, byte [rax]
+	mov [r12], rax
+	ret
+    ret
+word_c_21:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	mov [rbx], al
+	ret
+    ret
+word_r_40:
+	mov rax, [r13]
+	sub r12, 8
+	mov [r12], rax
+	ret
+    ret
+word_puts:
+	; detects string if top is len>=0 and next is a pointer in [data_start, data_end]
+	mov rax, [r12]      ; len or int value
+	mov rbx, [r12 + 8]  ; possible address
+	cmp rax, 0
+	jl puts_print_int
+	lea r8, [rel data_start]
+	lea r9, [rel data_end]
+	cmp rbx, r8
+	jl puts_print_int
+	cmp rbx, r9
+	jge puts_print_int
+	; treat as string: (addr below len)
+	mov rdx, rax        ; len
+	mov rsi, rbx        ; addr
+	add r12, 16         ; pop len + addr
+	test rdx, rdx
+	jz puts_str_newline_only
+	mov rax, 1
+	mov rdi, 1
+	syscall
+puts_str_newline_only:
+	mov byte [rel print_buf], 10
+	mov rax, 1
+	mov rdi, 1
+	lea rsi, [rel print_buf]
+	mov rdx, 1
+	syscall
+	ret
+
+puts_print_int:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, rax
+	mov r8, 0
+	cmp rbx, 0
+	jge puts_abs
+	neg rbx
+	mov r8, 1
+puts_abs:
+	lea rsi, [rel print_buf_end]
+	mov rcx, 0
+	mov r10, 10
+	cmp rbx, 0
+	jne puts_digits
+	dec rsi
+	mov byte [rsi], '0'
+	inc rcx
+	jmp puts_sign
+puts_digits:
+puts_loop:
+	xor rdx, rdx
+	mov rax, rbx
+	div r10
+	add dl, '0'
+	dec rsi
+	mov [rsi], dl
+	inc rcx
+	mov rbx, rax
+	test rbx, rbx
+	jne puts_loop
+puts_sign:
+	cmp r8, 0
+	je puts_finish_digits
+	dec rsi
+	mov byte [rsi], '-'
+	inc rcx
+puts_finish_digits:
+	mov byte [rsi + rcx], 10
+	inc rcx
+	mov rax, 1
+	mov rdi, 1
+	mov rdx, rcx
+	mov r9, rsi
+	mov rsi, r9
+	syscall
+    ret
+word_dup:
+	mov rax, [r12]
+	sub r12, 8
+	mov [r12], rax
+    ret
+word_write_buf:
+	mov rdx, [r12]        ; len
+	mov rsi, [r12 + 8]    ; addr
+	add r12, 16           ; pop len + addr
+	mov rax, 1            ; syscall: write
+	mov rdi, 1            ; fd = stdout
+	syscall
+	ret
+    ret
+word_drop:
+	add r12, 8
+    ret
+word_over:
+	mov rax, [r12 + 8]
+	sub r12, 8
+	mov [r12], rax
+    ret
+word_swap:
+	mov rax, [r12]
+	mov rbx, [r12 + 8]
+	mov [r12], rbx
+	mov [r12 + 8], rax
+    ret
+word_rot:
+	mov rax, [r12]       ; x3
+	mov rbx, [r12 + 8]   ; x2
+	mov rcx, [r12 + 16]  ; x1
+	mov [r12], rcx       ; top = x1
+	mov [r12 + 8], rax   ; next = x3
+	mov [r12 + 16], rbx  ; third = x2
+    ret
+word__2drot:
+	mov rax, [r12]       ; x3
+	mov rbx, [r12 + 8]   ; x2
+	mov rcx, [r12 + 16]  ; x1
+	mov [r12], rbx       ; top = x2
+	mov [r12 + 8], rcx   ; next = x1
+	mov [r12 + 16], rax  ; third = x3
+    ret
+word_nip:
+	mov rax, [r12]
+	add r12, 8           ; drop lower element
+	mov [r12], rax       ; keep original top
+    ret
+word_tuck:
+	mov rax, [r12]       ; x2
+	mov rbx, [r12 + 8]   ; x1
+	sub r12, 8           ; make room
+	mov [r12], rax       ; x2
+	mov [r12 + 8], rbx   ; x1
+	mov [r12 + 16], rax  ; x2
+    ret
+word_2dup:
+	mov rax, [r12]       ; b
+	mov rbx, [r12 + 8]   ; a
+	sub r12, 8
+	mov [r12], rbx       ; push a
+	sub r12, 8
+	mov [r12], rax       ; push b
+    ret
+word_2drop:
+	add r12, 16
+    ret
+word_2swap:
+	mov rax, [r12]        ; d
+	mov rbx, [r12 + 8]    ; c
+	mov rcx, [r12 + 16]   ; b
+	mov rdx, [r12 + 24]   ; a
+	mov [r12], rcx        ; top = b
+	mov [r12 + 8], rdx    ; next = a
+	mov [r12 + 16], rax   ; third = d
+	mov [r12 + 24], rbx   ; fourth = c
+    ret
+word_2over:
+	mov rax, [r12 + 16]   ; b
+	mov rbx, [r12 + 24]   ; a
+	sub r12, 8
+	mov [r12], rbx        ; push a
+	sub r12, 8
+	mov [r12], rax        ; push b
+    ret
+word__2b:
+	mov rax, [r12]
+	add r12, 8
+	add qword [r12], rax
+    ret
+word__2d:
+	mov rax, [r12]
+	add r12, 8
+	sub qword [r12], rax
+    ret
+word__2a:
+	mov rax, [r12]
+	add r12, 8
+	imul qword [r12]
+	mov [r12], rax
+    ret
+word__2f:
+	mov rbx, [r12]
+	add r12, 8
+	mov rax, [r12]
+	cqo
+	idiv rbx
+	mov [r12], rax
+    ret
+word__25:
+	mov rbx, [r12]
+	add r12, 8
+	mov rax, [r12]
+	cqo
+	idiv rbx
+	mov [r12], rdx
+    ret
+word__3d_3d:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	cmp rbx, rax
+	mov rbx, 0
+	sete bl
+	mov [r12], rbx
+    ret
+word__21_3d:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	cmp rbx, rax
+	mov rbx, 0
+	setne bl
+	mov [r12], rbx
+    ret
+word__3c:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	cmp rbx, rax
+	mov rbx, 0
+	setl bl
+	mov [r12], rbx
+    ret
+word__3e:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	cmp rbx, rax
+	mov rbx, 0
+	setg bl
+	mov [r12], rbx
+    ret
+word__3c_3d:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	cmp rbx, rax
+	mov rbx, 0
+	setle bl
+	mov [r12], rbx
+    ret
+word__3e_3d:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	cmp rbx, rax
+	mov rbx, 0
+	setge bl
+	mov [r12], rbx
+    ret
+word__40:
+	mov rax, [r12]
+	mov rax, [rax]
+	mov [r12], rax
+    ret
+word__21:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	mov [rax], rbx
+	add r12, 8
+    ret
+word_mmap:
+    ; Save rsp and align to 16 bytes for syscall ABI
+    mov rax, rsp
+    and rsp, -16
+    mov rdi, [r12+40]   ; addr
+    mov rsi, [r12+32]   ; length
+    mov rdx, [r12+24]   ; prot
+    mov r10, [r12+16]   ; flags
+    mov r8,  [r12+8]    ; fd
+    mov r9,  [r12]      ; offset
+    add r12, 48         ; pop 6 args
+    mov rax, 9          ; syscall: mmap
+    syscall
+    mov rsp, rax        ; restore rsp
+    sub r12, 8
+    mov [r12], rax      ; push result
+    ret
+    ret
+word_munmap:
+	mov rsi, [r12]
+	add r12, 8
+	mov rdi, [r12]
+	mov rax, 11
+	syscall
+	mov [r12], rax
+    ret
+word_exit:
+	mov rdi, [r12]
+	add r12, 8
+	mov rax, 60
+	syscall
+    ret
+word_and:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	test rax, rax
+	setz cl
+	test rbx, rbx
+	setz dl
+	movzx rcx, cl
+	movzx rdx, dl
+	and rcx, rdx
+	mov [r12], rcx
+    ret
+word_or:
+	mov rax, [r12]
+	add r12, 8
+	mov rbx, [r12]
+	test rax, rax
+	setz cl
+	test rbx, rbx
+	setz dl
+	movzx rcx, cl
+	movzx rdx, dl
+	or rcx, rdx
+	mov [r12], rcx
+    ret
+word_not:
+	mov rax, [r12]
+	test rax, rax
+	setz al
+	movzx rax, al
+	mov [r12], rax
+    ret
+word__3er:
+	mov rax, [r12]
+	add r12, 8
+	sub r13, 8
+	mov [r13], rax
+    ret
+word_r_3e:
+	mov rax, [r13]
+	add r13, 8
+	sub r12, 8
+	mov [r12], rax
+    ret
+word_rdrop:
+	add r13, 8
+    ret
+word_pick:
+	mov rcx, [r12]
+	add r12, 8
+	mov rax, [r12 + rcx * 8]
+	sub r12, 8
+	mov [r12], rax
+    ret
+word_rpick:
+	mov rcx, [r12]
+	add r12, 8
+	mov rax, [r13 + rcx * 8]
+	sub r12, 8
+	mov [r12], rax
+    ret
+word_read_file:
+	; stack: path_ptr (top), path_len (next)
+	mov rsi, [r12]        ; path_ptr
+	mov rdx, [r12 + 8]    ; path_len
+	add r12, 16           ; pop args
+
+	; open(path_ptr, O_RDONLY=0, mode=0)
+	mov rax, 2            ; syscall: open
+	mov rdi, rsi          ; filename
+	xor rsi, rsi          ; flags = O_RDONLY
+	xor rdx, rdx          ; mode = 0
+	syscall
+	mov r10, rax          ; save open() result
+	cmp rax, 0
+	jl .fail_open
+	mov r8, rax           ; fd
+
+	; use lseek to determine file size: lseek(fd, 0, SEEK_END)
+	mov rax, 8            ; syscall: lseek
+	mov rdi, r8           ; fd
+	xor rsi, rsi          ; offset = 0
+	mov rdx, 2            ; SEEK_END
+	syscall
+	mov r11, rax          ; save lseek() result
+	cmp rax, 0
+	jl .close_fail_lseek
+	mov rsi, rax          ; length = size
+
+	; mmap(NULL, size, PROT_READ=1, MAP_PRIVATE=2, fd, 0)
+	mov rax, 9            ; syscall: mmap
+	xor rdi, rdi          ; addr = NULL
+	; rsi already holds length
+	mov rdx, 1            ; PROT_READ
+	mov r10, 2            ; MAP_PRIVATE
+	mov r8, r8            ; fd
+	xor r9, r9            ; offset = 0
+	syscall
+	mov rbx, rax          ; addr
+	mov r12, r12          ; (no-op, for debug)
+	mov rax, 3            ; syscall: close
+	mov rdi, r8           ; fd
+	syscall
+	cmp rbx, -4095
+	jae .fail_mmap
+	sub r12, 16
+	mov [r12], rsi        ; len (rsi held length across syscall)
+	mov [r12 + 8], rbx    ; addr
+	ret
+
+.close_fail_lseek:
+	mov rax, 3
+	mov rdi, r8
+	syscall
+	mov rax, r11          ; return lseek() error code
+	sub r12, 16
+	mov [r12], rax
+	mov qword [r12 + 8], -1
+	ret
+
+.fail_open:
+	mov rax, r10          ; return open() error code
+	sub r12, 16
+	mov [r12], rax
+	mov qword [r12 + 8], -2
+	ret
+
+.fail_mmap:
+	mov rax, -1           ; return mmap() error
+	sub r12, 16
+	mov [r12], rax
+	mov qword [r12 + 8], -3
+	ret
+    ret
+word_write_file:
+	; stack: path_ptr (top), path_len, buf_ptr, buf_len
+	mov rsi, [r12]        ; path_ptr
+	mov rdx, [r12 + 8]    ; path_len
+	mov r15, [r12 + 16]   ; buf_ptr (save in callee-saved r15)
+	mov r13, [r12 + 24]   ; buf_len (save in callee-saved r13)
+	add r12, 32           ; pop 4 args (we saved buf info)
+
+	; open(path_ptr, O_WRONLY|O_CREAT|O_TRUNC, 0666)
+	mov rdi, rsi          ; filename
+	mov rsi, 577          ; flags = O_WRONLY|O_CREAT|O_TRUNC
+	mov rdx, 438          ; mode = 0o666
+	mov rax, 2            ; syscall: open
+	syscall
+	cmp rax, 0
+	jl .fail_open
+	mov r9, rax           ; save fd
+
+	; write(fd, buf_ptr, buf_len) -- use preserved r15/r13 which survive syscalls
+	mov rax, 1            ; syscall: write
+	mov rdi, r9           ; fd
+	mov rsi, r15          ; buf_ptr
+	mov rdx, r13          ; buf_len
+	syscall
+	mov r10, rax          ; save write result
+	cmp r10, 0
+	jl .fail_write
+
+	; close(fd)
+	mov rax, 3            ; syscall: close
+	mov rdi, r9
+	syscall
+
+	sub r12, 8
+	mov [r12], r10
+	ret
+
+.fail_write:
+	mov rax, 3
+	mov rdi, r9
+	syscall
+	sub r12, 8
+	mov [r12], r10
+	ret
+
+.fail_open:
+	sub r12, 8
+	mov [r12], rax
+	ret
+    ret
+word_read_stdin:
+	; stack: max_len
+	mov r14, [r12]        ; max_len
+	add r12, 8            ; pop max_len
+
+	; mmap(NULL, max_len, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
+	mov rax, 9            ; syscall: mmap
+	xor rdi, rdi          ; addr = NULL
+	mov rsi, r14          ; length
+	mov rdx, 3            ; PROT_READ|PROT_WRITE
+	mov r10, 34           ; MAP_PRIVATE|MAP_ANONYMOUS
+	mov r8, -1            ; fd = -1
+	xor r9, r9            ; offset = 0
+	syscall
+	cmp rax, -4095
+	jae .fail_mmap
+	mov rbx, rax          ; buffer addr
+	xor rcx, rcx          ; bytes_read = 0
+
+.read_loop:
+	mov rax, 0            ; syscall: read
+	mov rdi, 0            ; fd = stdin
+	lea rsi, [rbx + rcx]  ; buf + offset
+	mov rdx, r14
+	sub rdx, rcx          ; remaining = max_len - bytes_read
+	syscall
+	cmp rax, 0
+	je .done_read
+	js .read_error
+	add rcx, rax
+	cmp rcx, r14
+	jl .read_loop
+
+.done_read:
+	; push len (rcx) then addr (rbx)
+	sub r12, 16
+	mov [r12], rcx
+	mov [r12 + 8], rbx
+	ret
+
+.read_error:
+	; return negative errno in rax, addr = 0
+	sub r12, 16
+	mov [r12], rax
+	mov qword [r12 + 8], 0
+	ret
+
+.fail_mmap:
+	sub r12, 16
+	mov qword [r12], -1
+	mov qword [r12 + 8], 0
+	ret
+    ret
+word_main:
+    ; push 1024
+    sub r12, 8
+    mov qword [r12], 1024
+    call word_read_stdin
+    call word_dup
+    ; push 0
+    sub r12, 8
+    mov qword [r12], 0
+    call word__3e
+    mov rax, [r12]
+    add r12, 8
+    test rax, rax
+    jz L_if_false_0
+    call word_write_buf
+    ; push 0
+    sub r12, 8
+    mov qword [r12], 0
+    call word_exit
+L_if_false_0:
+    ; push str_0
+    sub r12, 8
+    mov qword [r12], str_0
+    ; push 17
+    sub r12, 8
+    mov qword [r12], 17
+    call word_puts
+    call word_exit
+    ret
+section .data
+data_start:
+str_0: db 114, 101, 97, 100, 95, 115, 116, 100, 105, 110, 32, 102, 97, 105, 108, 101, 100, 0
+str_0_len equ 17
+data_end:
+section .bss
+align 16
+dstack: resb DSTK_BYTES
+dstack_top:
+align 16
+rstack: resb RSTK_BYTES
+rstack_top:
+align 16
+print_buf: resb PRINT_BUF_BYTES
+print_buf_end: