projects
/
rrq
/
jonasforth.git
/ commitdiff
commit
grep
author
committer
pickaxe
?
search:
re
summary
|
shortlog
|
log
|
commit
| commitdiff |
tree
raw
|
patch
|
inline
| side by side (parent:
4d23315
)
Add error handling to parse_number
author
Jonas Hvid
<mail@johv.dk>
Tue, 10 Dec 2019 14:51:24 +0000
(15:51 +0100)
committer
Jonas Hvid
<mail@johv.dk>
Tue, 10 Dec 2019 14:54:48 +0000
(15:54 +0100)
impl.asm
patch
|
blob
|
history
diff --git
a/impl.asm
b/impl.asm
index bb796ab19afa4ac21717928bebbe628cd84e6875..9ad22789eb587a03da91ae3773427543006a6253 100644
(file)
--- a/
impl.asm
+++ b/
impl.asm
@@
-1,5
+1,39
@@
segment readable executable
segment readable executable
+macro printlen msg, len {
+ push rsi
+ add rsp, 8
+
+ mov rsi, msg
+ mov rdx, len
+ mov rax, 1
+ mov rdi, 1
+ syscall
+
+ sub rsp, 8
+ pop rsi
+}
+
+macro newline {
+ push $A
+ printlen rsp, 1
+}
+
+macro print msg {
+ printlen msg, msg#.len
+}
+
+macro exit code {
+ mov rax, $3C
+ mov rdi, code
+ syscall
+}
+
+struc string bytes {
+ . db bytes
+ .len = $ - .
+}
+
;; Find the given word in the dictionary of words. If no such word exists,
;; return 0.
;;
;; Find the given word in the dictionary of words. If no such word exists,
;; return 0.
;;
@@
-125,12
+159,15
@@
parse_number:
;; Now, rax = 10^(rcx - 1).
;; We need to calulate the value of the character at rdi[length - rcx].
;; Now, rax = 10^(rcx - 1).
;; We need to calulate the value of the character at rdi[length - rcx].
- mov rbx, rdi
+
mov rbx, rdi
add rbx, [.length]
sub rbx, rcx
movzx rbx, byte [rbx]
sub rbx, '0'
add rbx, [.length]
sub rbx, rcx
movzx rbx, byte [rbx]
sub rbx, '0'
+ cmp rbx, 10
+ jae .error
+
;; Multiply this value by rax to get (10^(rcx-1) * parse_char(rdi[length - rcx])),
;; then add this to the result.
mul rbx
;; Multiply this value by rax to get (10^(rcx-1) * parse_char(rdi[length - rcx])),
;; then add this to the result.
mul rbx
@@
-144,6
+181,13
@@
parse_number:
mov rax, r8
ret
mov rax, r8
ret
+.error:
+ push rdi
+ print parse_number.error_msg
+ pop rdi
+ printlen rdi, [.length]
+ newline
+ exit 100
segment readable writable
segment readable writable
@@
-156,4
+200,5
@@
read_word.length db ?
read_word.char_buffer db ?
parse_number.length dq ?
read_word.char_buffer db ?
parse_number.length dq ?
+parse_number.error_msg string "Invalid number: "