Optimize digit parse loops

strint.asm

@@ -66,12 +66,10 @@ add r2, r2, 1
 atoi_dec_loop:
 load_8 r3, [r2]
 atoi_dec_positive:
-cmp r3, 0x30 ; '0'
-jl atoi_done
-cmp r3, 0x39 ; '9'
-jg atoi_done
-add r2, r2, 1
 sub r3, r3, 0x30 ; '0'
+cmp r3, 9
+ja atoi_done
+add r2, r2, 1
 lsl flags, r1, 2        ; Use flags to help multiply by 10
 add r1, r1, flags
 lsl r1, r1, 1
@@ -105,12 +103,10 @@ jne atoi_bin_loop
 add r2, r2, 2
 atoi_bin_loop:
 load_8 r3, [r2]
-cmp r3, 0x30 ; '0'
-jl atoi_done
-cmp r3, 0x31 ; '1'
-jg atoi_done
-add r2, r2, 1
 sub r3, r3, 0x30 ; '0'
+cmp r3, 1
+ja atoi_done
+add r2, r2, 1
 lsl r1, r1, 1
 add r1, r1, r3
 jmp atoi_bin_loop
@@ -142,12 +138,10 @@ jne atoi_oct_loop
 add r2, r2, 2
 atoi_oct_loop:
 load_8 r3, [r2]
-cmp r3, 0x30 ; '0'
-jl atoi_done
-cmp r3, 0x37 ; '7'
-jg atoi_done
-add r2, r2, 1
 sub r3, r3, 0x30 ; '0'
+cmp r3, 7
+ja atoi_done
+add r2, r2, 1
 lsl r1, r1, 3
 add r1, r1, r3
 jmp atoi_oct_loop
@@ -175,28 +169,20 @@ atoi_hex_positive:
 load_16 r3, [r2]        ; check for prefix
 or r3, r3, 0x20         ; 2nd char to lower case
 cmp r3, 0x3078 ; "0x"
-jne atoi_oct_loop
+jne atoi_hex_loop
 add r2, r2, 2
 atoi_hex_loop:
 load_8 r3, [r2]
-cmp r3, 0x30 ; '0'
-jl atoi_done
-cmp r3, 0x39 ; '9'
-jg atoi_hex_letter
-add r2, r2, 1
 sub r3, r3, 0x30 ; '0'
-lsl r1, r1, 4
-add r1, r1, r3
-jmp atoi_hex_loop
-
-atoi_hex_letter:
-or r3, r3, 0x20 ; to lower case
-cmp r3, 0x61 ; 'a'
-jl atoi_done
-cmp r3, 0x66 ; 'f'
-jg atoi_done
+cmp r3, 10
+jb atoi_hex_add
+sub r3, r3, 0x11 ; 'A' - '0'
+and r3, r3, 0xdf        ; to lower case
+cmp r3, 5               ; 0-5: 6 letters
+ja atoi_done
+add r3, r3, 10          ; Adjust for digits below
+atoi_hex_add:
 add r2, r2, 1
-sub r3, r3, 0x57 ; 'a' - 10
 lsl r1, r1, 4
 add r1, r1, r3
 jmp atoi_hex_loop