1 ; shift_64.asm the nasm code is one sample, not unique
2 ;
3 ; compile: nasm -f elf64 -l shift_64.lst shift_64.asm
4 ; link: gcc -o shift_64 shift_64.o
5 ; run: ./shift_64 > shift_64.out
6 ;
7 ; the output from running shift.asm (zero filled) is:
8 ; shl rax,4, old rax=ABCDEF0987654321, new rax=BCDEF09876543210,
9 ; shl rax,8, old rax=ABCDEF0987654321, new rax=CDEF098765432100,
10 ; shr rax,4, old rax=ABCDEF0987654321, new rax= ABCDEF098765432,
11 ; sal rax,8, old rax=ABCDEF0987654321, new rax=CDEF098765432100,
12 ; sar rax,4, old rax=ABCDEF0987654321, new rax=FABCDEF098765432,
13 ; rol rax,4, old rax=ABCDEF0987654321, new rax=BCDEF0987654321A,
14 ; ror rax,4, old rax=ABCDEF0987654321, new rax=1ABCDEF098765432,
15 ; shld rdx,rax,8, old rdx:rax=0,ABCDEF0987654321,
16 ; new rax=ABCDEF0987654321 rdx= AB,
17 ; shl rax,8 , old rdx:rax=0,ABCDEF0987654321,
18 ; new rax=CDEF098765432100 rdx= AB,
19 ; shrd rdx,rax,8, old rdx:rax=0,ABCDEF0987654321,
20 ; new rax=ABCDEF0987654321 rdx=2100000000000000,
21 ; shr rax,8 , old rdx:rax=0,ABCDEF0987654321,
22 ; new rax= ABCDEF09876543 rdx=2100000000000000,
23
24 extern printf ; the C function to be called
25
26 %macro prt 1 ; old and new rax
27 section .data
28 .str db %1,0 ; %1 is which shift string
29 section .text
30 mov rdi, fmt ; address of format string
31 mov rsi, .str ; callers string
32 mov rdx,rax ; new value
33 mov rax, 0 ; no floating point
34 call printf ; Call C function
35 %endmacro
36
37 %macro prt2 1 ; old and new rax,rdx
38 section .data
39 .str db %1,0 ; %1 is which shift
40 section .text
41 mov rdi, fmt2 ; address of format string
42 mov rsi, .str ; callers string
43 mov rcx, rdx ; new rdx befor next because used
44 mov rdx, rax ; new rax
45 mov rax, 0 ; no floating point
46 call printf ; Call C function
47 %endmacro
48
49 section .bss
50 00000000 <res 00000008> raxsave: resq 1 ; save rax while calling a function
51 00000008 <res 00000008> rdxsave: resq 1 ; save rdx while calling a function
52
53 section .data ; preset constants, writeable
54 00000000 2143658709EFCDAB b64: dq 0xABCDEF0987654321 ; data to shift
55 00000008 25732C206F6C642072- fmt: db "%s, old rax=ABCDEF0987654321, new rax=%16lX, ",10,0 ; format string
56 00000011 61783D414243444546-
57 0000001A 303938373635343332-
58 00000023 312C206E6577207261-
59 0000002C 783D2531366C582C20-
60 00000035 0A00
61 00000037 25732C206F6C642072- fmt2: db "%s, old rdx:rax=0,ABCDEF0987654321,",10," new rax=%16lX rdx=%16lX, ",10,0
62 00000040 64783A7261783D302C-
63 00000049 414243444546303938-
64 00000052 373635343332312C0A-
65 0000005B 202020202020202020-
66 00000064 202020202020206E65-
67 0000006D 77207261783D253136-
68 00000076 6C58207264783D2531-
69 0000007F 366C582C200A00
70
71 section .text ; instructions, code segment
72 global main ; for gcc standard linking
73 00000000 55 main: push rbp ; set up stack
74
75 00000001 488B0425[00000000] shl1: mov rax, [b64] ; data to shift
76 00000009 48C1E004 shl rax, 4 ; shift rax 4 bits, one hex position left
77 prt "shl rax,4 " ; invoke the print macro
78 <1> section .data
79 00000086 73686C207261782C34- <1> .str db %1,0
80 0000008F 2000 <1>
81 <1> section .text
82 0000000D 48BF- <1> mov rdi, fmt
83 0000000F [0800000000000000] <1>
84 00000017 48BE- <1> mov rsi, .str
85 00000019 [8600000000000000] <1>
86 00000021 4889C2 <1> mov rdx,rax
87 00000024 B800000000 <1> mov rax, 0
88 00000029 E8(00000000) <1> call printf
89
90 0000002E 488B0425[00000000] shl4: mov rax, [b64] ; data to shift
91 00000036 48C1E008 shl rax,8 ; shift rax 8 bits. two hex positions left
92 prt "shl rax,8 " ; invoke the print macro
93 <1> section .data
94 00000091 73686C207261782C38- <1> .str db %1,0
95 0000009A 2000 <1>
96 <1> section .text
97 0000003A 48BF- <1> mov rdi, fmt
98 0000003C [0800000000000000] <1>
99 00000044 48BE- <1> mov rsi, .str
100 00000046 [9100000000000000] <1>
101 0000004E 4889C2 <1> mov rdx,rax
102 00000051 B800000000 <1> mov rax, 0
103 00000056 E8(00000000) <1> call printf
104
105 0000005B 488B0425[00000000] shr4: mov rax, [b64] ; data to shift
106 00000063 48C1E804 shr rax,4 ; shift
107 prt "shr rax,4 " ; invoke the print macro
108 <1> section .data
109 0000009C 736872207261782C34- <1> .str db %1,0
110 000000A5 2000 <1>
111 <1> section .text
112 00000067 48BF- <1> mov rdi, fmt
113 00000069 [0800000000000000] <1>
114 00000071 48BE- <1> mov rsi, .str
115 00000073 [9C00000000000000] <1>
116 0000007B 4889C2 <1> mov rdx,rax
117 0000007E B800000000 <1> mov rax, 0
118 00000083 E8(00000000) <1> call printf
119
120 00000088 488B0425[00000000] sal4: mov rax, [b64] ; data to shift
121 00000090 48C1E008 sal rax,8 ; shift
122 prt "sal rax,8 " ; invoke the print macro
123 <1> section .data
124 000000A7 73616C207261782C38- <1> .str db %1,0
125 000000B0 2000 <1>
126 <1> section .text
127 00000094 48BF- <1> mov rdi, fmt
128 00000096 [0800000000000000] <1>
129 0000009E 48BE- <1> mov rsi, .str
130 000000A0 [A700000000000000] <1>
131 000000A8 4889C2 <1> mov rdx,rax
132 000000AB B800000000 <1> mov rax, 0
133 000000B0 E8(00000000) <1> call printf
134
135 000000B5 488B0425[00000000] sar4: mov rax, [b64] ; data to shift
136 000000BD 48C1F804 sar rax,4 ; shift
137 prt "sar rax,4 " ; invoke the print macro
138 <1> section .data
139 000000B2 736172207261782C34- <1> .str db %1,0
140 000000BB 2000 <1>
141 <1> section .text
142 000000C1 48BF- <1> mov rdi, fmt
143 000000C3 [0800000000000000] <1>
144 000000CB 48BE- <1> mov rsi, .str
145 000000CD [B200000000000000] <1>
146 000000D5 4889C2 <1> mov rdx,rax
147 000000D8 B800000000 <1> mov rax, 0
148 000000DD E8(00000000) <1> call printf
149
150 000000E2 488B0425[00000000] rol4: mov rax, [b64] ; data to shift
151 000000EA 48C1C004 rol rax,4 ; shift
152 prt "rol rax,4 " ; invoke the print macro
153 <1> section .data
154 000000BD 726F6C207261782C34- <1> .str db %1,0
155 000000C6 2000 <1>
156 <1> section .text
157 000000EE 48BF- <1> mov rdi, fmt
158 000000F0 [0800000000000000] <1>
159 000000F8 48BE- <1> mov rsi, .str
160 000000FA [BD00000000000000] <1>
161 00000102 4889C2 <1> mov rdx,rax
162 00000105 B800000000 <1> mov rax, 0
163 0000010A E8(00000000) <1> call printf
164
165 0000010F 488B0425[00000000] ror4: mov rax, [b64] ; data to shift
166 00000117 48C1C804 ror rax,4 ; shift
167 prt "ror rax,4 " ; invoke the print macro
168 <1> section .data
169 000000C8 726F72207261782C34- <1> .str db %1,0
170 000000D1 2000 <1>
171 <1> section .text
172 0000011B 48BF- <1> mov rdi, fmt
173 0000011D [0800000000000000] <1>
174 00000125 48BE- <1> mov rsi, .str
175 00000127 [C800000000000000] <1>
176 0000012F 4889C2 <1> mov rdx,rax
177 00000132 B800000000 <1> mov rax, 0
178 00000137 E8(00000000) <1> call printf
179
180 0000013C 488B0425[00000000] shld4: mov rax, [b64] ; data to shift
181 00000144 BA00000000 mov rdx,0 ; register receiving bits
182 00000149 480FA4C208 shld rdx,rax,8 ; shift
183 0000014E 48890425[00000000] mov [raxsave],rax ; save, destroyed by function
184 00000156 48891425[08000000] mov [rdxsave],rdx ; save, destroyed by function
185 prt2 "shld rdx,rax,8"; invoke the print macro
186 <1> section .data
187 000000D3 73686C64207264782C- <1> .str db %1,0
188 000000DC 7261782C3800 <1>
189 <1> section .text
190 0000015E 48BF- <1> mov rdi, fmt2
191 00000160 [3700000000000000] <1>
192 00000168 48BE- <1> mov rsi, .str
193 0000016A [D300000000000000] <1>
194 00000172 4889D1 <1> mov rcx, rdx
195 00000175 4889C2 <1> mov rdx, rax
196 00000178 B800000000 <1> mov rax, 0
197 0000017D E8(00000000) <1> call printf
198
199 00000182 488B0425[00000000] shla: mov rax,[raxsave] ; restore, destroyed by function
200 0000018A 488B1425[08000000] mov rdx,[rdxsave] ; restore, destroyed by function
201 00000192 48C1E008 shl rax,8 ; finish double shift, both registers
202 prt2 "shl rax,8 "; invoke the print macro
203 <1> section .data
204 000000E2 73686C207261782C38- <1> .str db %1,0
205 000000EB 202020202000 <1>
206 <1> section .text
207 00000196 48BF- <1> mov rdi, fmt2
208 00000198 [3700000000000000] <1>
209 000001A0 48BE- <1> mov rsi, .str
210 000001A2 [E200000000000000] <1>
211 000001AA 4889D1 <1> mov rcx, rdx
212 000001AD 4889C2 <1> mov rdx, rax
213 000001B0 B800000000 <1> mov rax, 0
214 000001B5 E8(00000000) <1> call printf
215
216 000001BA 488B0425[00000000] shrd4: mov rax, [b64] ; data to shift
217 000001C2 BA00000000 mov rdx,0 ; register receiving bits
218 000001C7 480FACC208 shrd rdx,rax,8 ; shift
219 000001CC 48890425[00000000] mov [raxsave],rax ; save, destroyed by function
220 000001D4 48891425[08000000] mov [rdxsave],rdx ; save, destroyed by function
221 prt2 "shrd rdx,rax,8"; invoke the print macro
222 <1> section .data
223 000000F1 73687264207264782C- <1> .str db %1,0
224 000000FA 7261782C3800 <1>
225 <1> section .text
226 000001DC 48BF- <1> mov rdi, fmt2
227 000001DE [3700000000000000] <1>
228 000001E6 48BE- <1> mov rsi, .str
229 000001E8 [F100000000000000] <1>
230 000001F0 4889D1 <1> mov rcx, rdx
231 000001F3 4889C2 <1> mov rdx, rax
232 000001F6 B800000000 <1> mov rax, 0
233 000001FB E8(00000000) <1> call printf
234
235 00000200 488B0425[00000000] shra: mov rax,[raxsave] ; restore, destroyed by function
236 00000208 488B1425[08000000] mov rdx,[rdxsave] ; restore, destroyed by function
237 00000210 48C1E808 shr rax,8 ; finish double shift, both registers
238 prt2 "shr rax,8 "; invoke the print macro
239 <1> section .data
240 00000100 736872207261782C38- <1> .str db %1,0
241 00000109 202020202000 <1>
242 <1> section .text
243 00000214 48BF- <1> mov rdi, fmt2
244 00000216 [3700000000000000] <1>
245 0000021E 48BE- <1> mov rsi, .str
246 00000220 [0001000000000000] <1>
247 00000228 4889D1 <1> mov rcx, rdx
248 0000022B 4889C2 <1> mov rdx, rax
249 0000022E B800000000 <1> mov rax, 0
250 00000233 E8(00000000) <1> call printf
251
252 00000238 5D pop rbp ; restore stack
253 00000239 B800000000 mov rax,0 ; exit code, 0=normal
254 0000023E C3 ret ; main returns to operating system
255