Commit | Line | Data |
---|---|---|
b90efa5b | 1 | @c Copyright (C) 2002-2015 Free Software Foundation, Inc. |
2469cfa2 NC |
2 | @c This is part of the GAS manual. |
3 | @c For copying conditions, see the file as.texinfo. | |
4 | @ifset GENERIC | |
5 | @page | |
6 | @node MSP430-Dependent | |
7 | @chapter MSP 430 Dependent Features | |
8 | @end ifset | |
9 | @ifclear GENERIC | |
10 | @node Machine Dependencies | |
11 | @chapter MSP 430 Dependent Features | |
12 | @end ifclear | |
13 | ||
14 | @cindex MSP 430 support | |
15 | @cindex 430 support | |
16 | @menu | |
17 | * MSP430 Options:: Options | |
18 | * MSP430 Syntax:: Syntax | |
19 | * MSP430 Floating Point:: Floating Point | |
20 | * MSP430 Directives:: MSP 430 Machine Directives | |
21 | * MSP430 Opcodes:: Opcodes | |
b18c562e | 22 | * MSP430 Profiling Capability:: Profiling Capability |
2469cfa2 NC |
23 | @end menu |
24 | ||
25 | @node MSP430 Options | |
26 | @section Options | |
27 | @cindex MSP 430 options (none) | |
28 | @cindex options for MSP430 (none) | |
77592908 DD |
29 | @table @code |
30 | ||
638d3803 | 31 | @item -mmcu |
65d7bab5 NC |
32 | selects the mcu architecture. If the architecture is 430Xv2 then this |
33 | also enables NOP generation unless the @option{-mN} is also specified. | |
638d3803 | 34 | |
997b26e8 | 35 | @item -mcpu |
638d3803 | 36 | selects the cpu architecture. If the architecture is 430Xv2 then this |
65d7bab5 | 37 | also enables NOP generation unless the @option{-mN} is also specified. |
638d3803 | 38 | |
34bca508 | 39 | @item -mP |
77592908 DD |
40 | enables polymorph instructions handler. |
41 | ||
34bca508 | 42 | @item -mQ |
77592908 DD |
43 | enables relaxation at assembly time. DANGEROUS! |
44 | ||
13761a11 NC |
45 | @item -ml |
46 | indicates that the input uses the large code model. | |
47 | ||
a75555d1 NC |
48 | @item -mn |
49 | enables the generation of a NOP instruction following any instruction | |
50 | that might change the interrupts enabled/disabled state. The | |
51 | pipelined nature of the MSP430 core means that any instruction that | |
52 | changes the interrupt state (@code{EINT}, @code{DINT}, @code{BIC #8, | |
53 | SR}, @code{BIS #8, SR} or @code{MOV.W <>, SR}) must be | |
54 | followed by a NOP instruction in order to ensure the correct | |
55 | processing of interrupts. By default it is up to the programmer to | |
56 | supply these NOP instructions, but this command line option enables | |
65d7bab5 | 57 | the automatic insertion by the assembler, if they are missing. |
a75555d1 | 58 | |
13761a11 NC |
59 | @item -mN |
60 | disables the generation of a NOP instruction following any instruction | |
a75555d1 NC |
61 | that might change the interrupts enabled/disabled state. This is the |
62 | default behaviour. | |
13761a11 | 63 | |
69227609 | 64 | @item -my |
65d7bab5 NC |
65 | tells the assembler to generate a warning message if a NOP does not |
66 | immediately forllow an instruction that enables or disables | |
67 | interrupts. This is the default. | |
68 | ||
69 | Note that this option can be stacked with the @option{-mn} option so | |
70 | that the assembler will both warn about missing NOP instructions and | |
71 | then insert them automatically. | |
72 | ||
69227609 | 73 | @item -mY |
65d7bab5 NC |
74 | disables warnings about missing NOP instructions. |
75 | ||
ab905915 NC |
76 | @item -md |
77 | mark the object file as one that requires data to copied from ROM to | |
78 | RAM at execution startup. Disabled by default. | |
79 | ||
77592908 | 80 | @end table |
2469cfa2 NC |
81 | |
82 | @node MSP430 Syntax | |
83 | @section Syntax | |
84 | @menu | |
85 | * MSP430-Macros:: Macros | |
86 | * MSP430-Chars:: Special Characters | |
87 | * MSP430-Regs:: Register Names | |
88 | * MSP430-Ext:: Assembler Extensions | |
89 | @end menu | |
90 | ||
91 | @node MSP430-Macros | |
92 | @subsection Macros | |
93 | ||
94 | @cindex Macros, MSP 430 | |
95 | @cindex MSP 430 macros | |
96 | The macro syntax used on the MSP 430 is like that described in the MSP | |
97 | 430 Family Assembler Specification. Normal @code{@value{AS}} | |
98 | macros should still work. | |
99 | ||
100 | Additional built-in macros are: | |
101 | ||
102 | @table @code | |
103 | ||
34bca508 | 104 | @item llo(exp) |
2469cfa2 NC |
105 | Extracts least significant word from 32-bit expression 'exp'. |
106 | ||
107 | @item lhi(exp) | |
108 | Extracts most significant word from 32-bit expression 'exp'. | |
109 | ||
110 | @item hlo(exp) | |
111 | Extracts 3rd word from 64-bit expression 'exp'. | |
112 | ||
34bca508 | 113 | @item hhi(exp) |
2469cfa2 NC |
114 | Extracts 4rd word from 64-bit expression 'exp'. |
115 | ||
116 | @end table | |
117 | ||
118 | They normally being used as an immediate source operand. | |
119 | @smallexample | |
34bca508 | 120 | mov #llo(1), r10 ; == mov #1, r10 |
2469cfa2 NC |
121 | mov #lhi(1), r10 ; == mov #0, r10 |
122 | @end smallexample | |
34bca508 | 123 | |
2469cfa2 NC |
124 | @node MSP430-Chars |
125 | @subsection Special Characters | |
126 | ||
127 | @cindex line comment character, MSP 430 | |
128 | @cindex MSP 430 line comment character | |
7c31ae13 NC |
129 | A semicolon (@samp{;}) appearing anywhere on a line starts a comment |
130 | that extends to the end of that line. | |
131 | ||
132 | If a @samp{#} appears as the first character of a line then the whole | |
133 | line is treated as a comment, but it can also be a logical line number | |
134 | directive (@pxref{Comments}) or a preprocessor control command | |
135 | (@pxref{Preprocessing}). | |
136 | ||
137 | @cindex line separator, MSP 430 | |
138 | @cindex statement separator, MSP 430 | |
139 | @cindex MSP 430 line separator | |
140 | Multiple statements can appear on the same line provided that they are | |
141 | separated by the @samp{@{} character. | |
2469cfa2 NC |
142 | |
143 | @cindex identifiers, MSP 430 | |
144 | @cindex MSP 430 identifiers | |
34bca508 | 145 | The character @samp{$} in jump instructions indicates current location and |
2469cfa2 NC |
146 | implemented only for TI syntax compatibility. |
147 | ||
148 | @node MSP430-Regs | |
149 | @subsection Register Names | |
150 | ||
151 | @cindex MSP 430 register names | |
152 | @cindex register names, MSP 430 | |
153 | General-purpose registers are represented by predefined symbols of the | |
154 | form @samp{r@var{N}} (for global registers), where @var{N} represents | |
155 | a number between @code{0} and @code{15}. The leading | |
156 | letters may be in either upper or lower case; for example, @samp{r13} | |
157 | and @samp{R7} are both valid register names. | |
158 | ||
159 | @cindex special purpose registers, MSP 430 | |
160 | Register names @samp{PC}, @samp{SP} and @samp{SR} cannot be used as register names | |
161 | and will be treated as variables. Use @samp{r0}, @samp{r1}, and @samp{r2} instead. | |
162 | ||
163 | ||
164 | @node MSP430-Ext | |
165 | @subsection Assembler Extensions | |
166 | @cindex MSP430 Assembler Extensions | |
167 | ||
168 | @table @code | |
169 | ||
170 | @item @@rN | |
171 | As destination operand being treated as @samp{0(rn)} | |
172 | ||
173 | @item 0(rN) | |
174 | As source operand being treated as @samp{@@rn} | |
175 | ||
176 | @item jCOND +N | |
177 | Skips next N bytes followed by jump instruction and equivalent to | |
178 | @samp{jCOND $+N+2} | |
179 | ||
180 | @end table | |
181 | ||
b18c562e NC |
182 | Also, there are some instructions, which cannot be found in other assemblers. |
183 | These are branch instructions, which has different opcodes upon jump distance. | |
184 | They all got PC relative addressing mode. | |
185 | ||
186 | @table @code | |
187 | @item beq label | |
188 | A polymorph instruction which is @samp{jeq label} in case if jump distance | |
189 | within allowed range for cpu's jump instruction. If not, this unrolls into | |
190 | a sequence of | |
191 | @smallexample | |
192 | jne $+6 | |
193 | br label | |
194 | @end smallexample | |
195 | ||
196 | @item bne label | |
197 | A polymorph instruction which is @samp{jne label} or @samp{jeq +4; br label} | |
198 | ||
199 | @item blt label | |
200 | A polymorph instruction which is @samp{jl label} or @samp{jge +4; br label} | |
201 | ||
202 | @item bltn label | |
203 | A polymorph instruction which is @samp{jn label} or @samp{jn +2; jmp +4; br label} | |
204 | ||
205 | @item bltu label | |
206 | A polymorph instruction which is @samp{jlo label} or @samp{jhs +2; br label} | |
207 | ||
208 | @item bge label | |
209 | A polymorph instruction which is @samp{jge label} or @samp{jl +4; br label} | |
210 | ||
211 | @item bgeu label | |
212 | A polymorph instruction which is @samp{jhs label} or @samp{jlo +4; br label} | |
213 | ||
214 | @item bgt label | |
215 | A polymorph instruction which is @samp{jeq +2; jge label} or @samp{jeq +6; jl +4; br label} | |
216 | ||
217 | @item bgtu label | |
218 | A polymorph instruction which is @samp{jeq +2; jhs label} or @samp{jeq +6; jlo +4; br label} | |
219 | ||
220 | @item bleu label | |
221 | A polymorph instruction which is @samp{jeq label; jlo label} or @samp{jeq +2; jhs +4; br label} | |
222 | ||
223 | @item ble label | |
224 | A polymorph instruction which is @samp{jeq label; jl label} or @samp{jeq +2; jge +4; br label} | |
225 | ||
226 | @item jump label | |
227 | A polymorph instruction which is @samp{jmp label} or @samp{br label} | |
228 | @end table | |
229 | ||
2469cfa2 NC |
230 | |
231 | @node MSP430 Floating Point | |
232 | @section Floating Point | |
233 | ||
234 | @cindex floating point, MSP 430 (@sc{ieee}) | |
235 | @cindex MSP 430 floating point (@sc{ieee}) | |
236 | The MSP 430 family uses @sc{ieee} 32-bit floating-point numbers. | |
237 | ||
238 | @node MSP430 Directives | |
239 | @section MSP 430 Machine Directives | |
240 | ||
241 | @cindex machine directives, MSP 430 | |
242 | @cindex MSP 430 machine directives | |
243 | @table @code | |
244 | @cindex @code{file} directive, MSP 430 | |
245 | @item .file | |
246 | This directive is ignored; it is accepted for compatibility with other | |
247 | MSP 430 assemblers. | |
248 | ||
249 | @quotation | |
250 | @emph{Warning:} in other versions of the @sc{gnu} assembler, @code{.file} is | |
251 | used for the directive called @code{.app-file} in the MSP 430 support. | |
252 | @end quotation | |
253 | ||
254 | @cindex @code{line} directive, MSP 430 | |
255 | @item .line | |
256 | This directive is ignored; it is accepted for compatibility with other | |
257 | MSP 430 assemblers. | |
258 | ||
638d3803 | 259 | @cindex @code{arch} directive, MSP 430 |
2469cfa2 | 260 | @item .arch |
638d3803 NC |
261 | Sets the target microcontroller in the same way as the @option{-mmcu} |
262 | command line option. | |
263 | ||
264 | @cindex @code{cpu} directive, MSP 430 | |
265 | @item .cpu | |
266 | Sets the target architecture in the same way as the @option{-mcpu} | |
267 | command line option. | |
2469cfa2 | 268 | |
b18c562e NC |
269 | @cindex @code{profiler} directive, MSP 430 |
270 | @item .profiler | |
271 | This directive instructs assembler to add new profile entry to the object file. | |
272 | ||
96b96102 DD |
273 | @cindex @code{refsym} directive, MSP 430 |
274 | @item .refsym | |
275 | This directive instructs assembler to add an undefined reference to | |
276 | the symbol following the directive. The maximum symbol name length is | |
277 | 1023 characters. No relocation is created for this symbol; it will | |
278 | exist purely for pulling in object files from archives. Note that | |
279 | this reloc is not sufficient to prevent garbage collection; use a | |
280 | KEEP() directive in the linker file to preserve such objects. | |
281 | ||
2469cfa2 NC |
282 | @end table |
283 | ||
284 | @node MSP430 Opcodes | |
285 | @section Opcodes | |
286 | ||
287 | @cindex MSP 430 opcodes | |
288 | @cindex opcodes for MSP 430 | |
289 | @code{@value{AS}} implements all the standard MSP 430 opcodes. No | |
290 | additional pseudo-instructions are needed on this family. | |
291 | ||
292 | For information on the 430 machine instruction set, see @cite{MSP430 | |
77592908 | 293 | User's Manual, document slau049d}, Texas Instrument, Inc. |
b18c562e NC |
294 | |
295 | @node MSP430 Profiling Capability | |
296 | @section Profiling Capability | |
297 | ||
298 | @cindex MSP 430 profiling capability | |
299 | @cindex profiling capability for MSP 430 | |
300 | It is a performance hit to use gcc's profiling approach for this tiny target. | |
301 | Even more -- jtag hardware facility does not perform any profiling functions. | |
302 | However we've got gdb's built-in simulator where we can do anything. | |
303 | ||
304 | We define new section @samp{.profiler} which holds all profiling information. | |
305 | We define new pseudo operation @samp{.profiler} which will instruct assembler to | |
306 | add new profile entry to the object file. Profile should take place at the | |
307 | present address. | |
308 | ||
309 | Pseudo operation format: | |
310 | ||
311 | @samp{.profiler flags,function_to_profile [, cycle_corrector, extra]} | |
312 | ||
313 | ||
314 | where: | |
315 | ||
316 | @table @code | |
317 | ||
318 | @table @code | |
319 | ||
320 | @samp{flags} is a combination of the following characters: | |
321 | ||
34bca508 | 322 | @item s |
b18c562e | 323 | function entry |
34bca508 | 324 | @item x |
b18c562e | 325 | function exit |
34bca508 | 326 | @item i |
b18c562e | 327 | function is in init section |
34bca508 | 328 | @item f |
b18c562e | 329 | function is in fini section |
34bca508 | 330 | @item l |
b18c562e | 331 | library call |
34bca508 | 332 | @item c |
b18c562e | 333 | libc standard call |
34bca508 | 334 | @item d |
b18c562e | 335 | stack value demand |
34bca508 | 336 | @item I |
b18c562e | 337 | interrupt service routine |
34bca508 | 338 | @item P |
b18c562e | 339 | prologue start |
34bca508 | 340 | @item p |
b18c562e | 341 | prologue end |
34bca508 | 342 | @item E |
b18c562e | 343 | epilogue start |
34bca508 | 344 | @item e |
b18c562e | 345 | epilogue end |
34bca508 | 346 | @item j |
b18c562e | 347 | long jump / sjlj unwind |
34bca508 | 348 | @item a |
b18c562e NC |
349 | an arbitrary code fragment |
350 | @item t | |
351 | extra parameter saved (a constant value like frame size) | |
352 | @end table | |
353 | ||
34bca508 | 354 | @item function_to_profile |
b18c562e | 355 | a function address |
34bca508 | 356 | @item cycle_corrector |
b18c562e | 357 | a value which should be added to the cycle counter, zero if omitted. |
34bca508 | 358 | @item extra |
b18c562e NC |
359 | any extra parameter, zero if omitted. |
360 | ||
361 | @end table | |
362 | ||
363 | For example: | |
364 | @smallexample | |
365 | .global fxx | |
366 | .type fxx,@@function | |
367 | fxx: | |
368 | .LFrameOffset_fxx=0x08 | |
369 | .profiler "scdP", fxx ; function entry. | |
370 | ; we also demand stack value to be saved | |
371 | push r11 | |
372 | push r10 | |
373 | push r9 | |
374 | push r8 | |
375 | .profiler "cdpt",fxx,0, .LFrameOffset_fxx ; check stack value at this point | |
376 | ; (this is a prologue end) | |
34bca508 | 377 | ; note, that spare var filled with |
b18c562e NC |
378 | ; the farme size |
379 | mov r15,r8 | |
380 | ... | |
381 | .profiler cdE,fxx ; check stack | |
382 | pop r8 | |
383 | pop r9 | |
384 | pop r10 | |
385 | pop r11 | |
386 | .profiler xcde,fxx,3 ; exit adds 3 to the cycle counter | |
387 | ret ; cause 'ret' insn takes 3 cycles | |
388 | @end smallexample |