]>
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 | |
2213f746 NC |
39 | @item -msilicon-errata=@var{name}[,@var{name}@dots{}] |
40 | Implements a fixup for named silicon errata. Multiple silicon errata | |
41 | can be specified by multiple uses of the @option{-msilicon-errata} | |
42 | option and/or by including the errata names, separated by commas, on | |
43 | an individual @option{-msilicon-errata} option. Errata names | |
44 | currently recognised by the assembler are: | |
45 | ||
46 | @table @code | |
47 | @item cpu4 | |
48 | @code{PUSH #4} and @option{PUSH #8} need longer encodings on the | |
49 | MSP430. This option is enabled by default, and cannot be disabled. | |
50 | @item cpu8 | |
51 | Do not set the @code{SP} to an odd value. | |
52 | @item cpu11 | |
53 | Do not update the @code{SR} and the @code{PC} in the same instruction. | |
54 | @item cpu12 | |
55 | Do not use the @code{PC} in a @code{CMP} or @code{BIT} instruction. | |
56 | @item cpu13 | |
57 | Do not use an arithmetic instruction to modify the @code{SR}. | |
58 | @item cpu19 | |
59 | Insert @code{NOP} after @code{CPUOFF}. | |
60 | @item cpu42 | |
61 | Warn where a @code{NOP} ought to be present after enabling interrupts. | |
62 | @item cpu42+ | |
63 | Add @code{NOP} after enabling interrupts. | |
64 | @end table | |
65 | ||
66 | @item -msilicon-errata-warn=@var{name}[,@var{name}@dots{}] | |
67 | Like the @option{-msilicon-errata} option except that instead of | |
68 | fixing the specified errata, a warning message is issued instead. | |
69 | This option can be used alongside @option{-msilicon-errata} to | |
70 | generate messages whenever a problem is fixed, or on its own in order | |
71 | to inspect code for potential problems. | |
72 | ||
34bca508 | 73 | @item -mP |
77592908 DD |
74 | enables polymorph instructions handler. |
75 | ||
34bca508 | 76 | @item -mQ |
77592908 DD |
77 | enables relaxation at assembly time. DANGEROUS! |
78 | ||
13761a11 NC |
79 | @item -ml |
80 | indicates that the input uses the large code model. | |
81 | ||
a75555d1 NC |
82 | @item -mn |
83 | enables the generation of a NOP instruction following any instruction | |
84 | that might change the interrupts enabled/disabled state. The | |
85 | pipelined nature of the MSP430 core means that any instruction that | |
86 | changes the interrupt state (@code{EINT}, @code{DINT}, @code{BIC #8, | |
87 | SR}, @code{BIS #8, SR} or @code{MOV.W <>, SR}) must be | |
88 | followed by a NOP instruction in order to ensure the correct | |
89 | processing of interrupts. By default it is up to the programmer to | |
90 | supply these NOP instructions, but this command line option enables | |
65d7bab5 | 91 | the automatic insertion by the assembler, if they are missing. |
a75555d1 | 92 | |
13761a11 NC |
93 | @item -mN |
94 | disables the generation of a NOP instruction following any instruction | |
a75555d1 NC |
95 | that might change the interrupts enabled/disabled state. This is the |
96 | default behaviour. | |
13761a11 | 97 | |
69227609 | 98 | @item -my |
65d7bab5 NC |
99 | tells the assembler to generate a warning message if a NOP does not |
100 | immediately forllow an instruction that enables or disables | |
101 | interrupts. This is the default. | |
102 | ||
103 | Note that this option can be stacked with the @option{-mn} option so | |
104 | that the assembler will both warn about missing NOP instructions and | |
105 | then insert them automatically. | |
106 | ||
69227609 | 107 | @item -mY |
65d7bab5 NC |
108 | disables warnings about missing NOP instructions. |
109 | ||
ab905915 NC |
110 | @item -md |
111 | mark the object file as one that requires data to copied from ROM to | |
112 | RAM at execution startup. Disabled by default. | |
113 | ||
77592908 | 114 | @end table |
2469cfa2 NC |
115 | |
116 | @node MSP430 Syntax | |
117 | @section Syntax | |
118 | @menu | |
119 | * MSP430-Macros:: Macros | |
120 | * MSP430-Chars:: Special Characters | |
121 | * MSP430-Regs:: Register Names | |
122 | * MSP430-Ext:: Assembler Extensions | |
123 | @end menu | |
124 | ||
125 | @node MSP430-Macros | |
126 | @subsection Macros | |
127 | ||
128 | @cindex Macros, MSP 430 | |
129 | @cindex MSP 430 macros | |
130 | The macro syntax used on the MSP 430 is like that described in the MSP | |
131 | 430 Family Assembler Specification. Normal @code{@value{AS}} | |
132 | macros should still work. | |
133 | ||
134 | Additional built-in macros are: | |
135 | ||
136 | @table @code | |
137 | ||
34bca508 | 138 | @item llo(exp) |
2469cfa2 NC |
139 | Extracts least significant word from 32-bit expression 'exp'. |
140 | ||
141 | @item lhi(exp) | |
142 | Extracts most significant word from 32-bit expression 'exp'. | |
143 | ||
144 | @item hlo(exp) | |
145 | Extracts 3rd word from 64-bit expression 'exp'. | |
146 | ||
34bca508 | 147 | @item hhi(exp) |
2469cfa2 NC |
148 | Extracts 4rd word from 64-bit expression 'exp'. |
149 | ||
150 | @end table | |
151 | ||
152 | They normally being used as an immediate source operand. | |
153 | @smallexample | |
34bca508 | 154 | mov #llo(1), r10 ; == mov #1, r10 |
2469cfa2 NC |
155 | mov #lhi(1), r10 ; == mov #0, r10 |
156 | @end smallexample | |
34bca508 | 157 | |
2469cfa2 NC |
158 | @node MSP430-Chars |
159 | @subsection Special Characters | |
160 | ||
161 | @cindex line comment character, MSP 430 | |
162 | @cindex MSP 430 line comment character | |
7c31ae13 NC |
163 | A semicolon (@samp{;}) appearing anywhere on a line starts a comment |
164 | that extends to the end of that line. | |
165 | ||
166 | If a @samp{#} appears as the first character of a line then the whole | |
167 | line is treated as a comment, but it can also be a logical line number | |
168 | directive (@pxref{Comments}) or a preprocessor control command | |
169 | (@pxref{Preprocessing}). | |
170 | ||
171 | @cindex line separator, MSP 430 | |
172 | @cindex statement separator, MSP 430 | |
173 | @cindex MSP 430 line separator | |
174 | Multiple statements can appear on the same line provided that they are | |
175 | separated by the @samp{@{} character. | |
2469cfa2 NC |
176 | |
177 | @cindex identifiers, MSP 430 | |
178 | @cindex MSP 430 identifiers | |
34bca508 | 179 | The character @samp{$} in jump instructions indicates current location and |
2469cfa2 NC |
180 | implemented only for TI syntax compatibility. |
181 | ||
182 | @node MSP430-Regs | |
183 | @subsection Register Names | |
184 | ||
185 | @cindex MSP 430 register names | |
186 | @cindex register names, MSP 430 | |
187 | General-purpose registers are represented by predefined symbols of the | |
188 | form @samp{r@var{N}} (for global registers), where @var{N} represents | |
189 | a number between @code{0} and @code{15}. The leading | |
190 | letters may be in either upper or lower case; for example, @samp{r13} | |
191 | and @samp{R7} are both valid register names. | |
192 | ||
193 | @cindex special purpose registers, MSP 430 | |
194 | Register names @samp{PC}, @samp{SP} and @samp{SR} cannot be used as register names | |
195 | and will be treated as variables. Use @samp{r0}, @samp{r1}, and @samp{r2} instead. | |
196 | ||
197 | ||
198 | @node MSP430-Ext | |
199 | @subsection Assembler Extensions | |
200 | @cindex MSP430 Assembler Extensions | |
201 | ||
202 | @table @code | |
203 | ||
204 | @item @@rN | |
205 | As destination operand being treated as @samp{0(rn)} | |
206 | ||
207 | @item 0(rN) | |
208 | As source operand being treated as @samp{@@rn} | |
209 | ||
210 | @item jCOND +N | |
211 | Skips next N bytes followed by jump instruction and equivalent to | |
212 | @samp{jCOND $+N+2} | |
213 | ||
214 | @end table | |
215 | ||
b18c562e NC |
216 | Also, there are some instructions, which cannot be found in other assemblers. |
217 | These are branch instructions, which has different opcodes upon jump distance. | |
218 | They all got PC relative addressing mode. | |
219 | ||
220 | @table @code | |
221 | @item beq label | |
222 | A polymorph instruction which is @samp{jeq label} in case if jump distance | |
223 | within allowed range for cpu's jump instruction. If not, this unrolls into | |
224 | a sequence of | |
225 | @smallexample | |
226 | jne $+6 | |
227 | br label | |
228 | @end smallexample | |
229 | ||
230 | @item bne label | |
231 | A polymorph instruction which is @samp{jne label} or @samp{jeq +4; br label} | |
232 | ||
233 | @item blt label | |
234 | A polymorph instruction which is @samp{jl label} or @samp{jge +4; br label} | |
235 | ||
236 | @item bltn label | |
237 | A polymorph instruction which is @samp{jn label} or @samp{jn +2; jmp +4; br label} | |
238 | ||
239 | @item bltu label | |
240 | A polymorph instruction which is @samp{jlo label} or @samp{jhs +2; br label} | |
241 | ||
242 | @item bge label | |
243 | A polymorph instruction which is @samp{jge label} or @samp{jl +4; br label} | |
244 | ||
245 | @item bgeu label | |
246 | A polymorph instruction which is @samp{jhs label} or @samp{jlo +4; br label} | |
247 | ||
248 | @item bgt label | |
249 | A polymorph instruction which is @samp{jeq +2; jge label} or @samp{jeq +6; jl +4; br label} | |
250 | ||
251 | @item bgtu label | |
252 | A polymorph instruction which is @samp{jeq +2; jhs label} or @samp{jeq +6; jlo +4; br label} | |
253 | ||
254 | @item bleu label | |
255 | A polymorph instruction which is @samp{jeq label; jlo label} or @samp{jeq +2; jhs +4; br label} | |
256 | ||
257 | @item ble label | |
258 | A polymorph instruction which is @samp{jeq label; jl label} or @samp{jeq +2; jge +4; br label} | |
259 | ||
260 | @item jump label | |
261 | A polymorph instruction which is @samp{jmp label} or @samp{br label} | |
262 | @end table | |
263 | ||
2469cfa2 NC |
264 | |
265 | @node MSP430 Floating Point | |
266 | @section Floating Point | |
267 | ||
268 | @cindex floating point, MSP 430 (@sc{ieee}) | |
269 | @cindex MSP 430 floating point (@sc{ieee}) | |
270 | The MSP 430 family uses @sc{ieee} 32-bit floating-point numbers. | |
271 | ||
272 | @node MSP430 Directives | |
273 | @section MSP 430 Machine Directives | |
274 | ||
275 | @cindex machine directives, MSP 430 | |
276 | @cindex MSP 430 machine directives | |
277 | @table @code | |
278 | @cindex @code{file} directive, MSP 430 | |
279 | @item .file | |
280 | This directive is ignored; it is accepted for compatibility with other | |
281 | MSP 430 assemblers. | |
282 | ||
283 | @quotation | |
284 | @emph{Warning:} in other versions of the @sc{gnu} assembler, @code{.file} is | |
285 | used for the directive called @code{.app-file} in the MSP 430 support. | |
286 | @end quotation | |
287 | ||
288 | @cindex @code{line} directive, MSP 430 | |
289 | @item .line | |
290 | This directive is ignored; it is accepted for compatibility with other | |
291 | MSP 430 assemblers. | |
292 | ||
638d3803 | 293 | @cindex @code{arch} directive, MSP 430 |
2469cfa2 | 294 | @item .arch |
638d3803 NC |
295 | Sets the target microcontroller in the same way as the @option{-mmcu} |
296 | command line option. | |
297 | ||
298 | @cindex @code{cpu} directive, MSP 430 | |
299 | @item .cpu | |
300 | Sets the target architecture in the same way as the @option{-mcpu} | |
301 | command line option. | |
2469cfa2 | 302 | |
b18c562e NC |
303 | @cindex @code{profiler} directive, MSP 430 |
304 | @item .profiler | |
305 | This directive instructs assembler to add new profile entry to the object file. | |
306 | ||
96b96102 DD |
307 | @cindex @code{refsym} directive, MSP 430 |
308 | @item .refsym | |
309 | This directive instructs assembler to add an undefined reference to | |
310 | the symbol following the directive. The maximum symbol name length is | |
311 | 1023 characters. No relocation is created for this symbol; it will | |
312 | exist purely for pulling in object files from archives. Note that | |
313 | this reloc is not sufficient to prevent garbage collection; use a | |
314 | KEEP() directive in the linker file to preserve such objects. | |
315 | ||
2469cfa2 NC |
316 | @end table |
317 | ||
318 | @node MSP430 Opcodes | |
319 | @section Opcodes | |
320 | ||
321 | @cindex MSP 430 opcodes | |
322 | @cindex opcodes for MSP 430 | |
323 | @code{@value{AS}} implements all the standard MSP 430 opcodes. No | |
324 | additional pseudo-instructions are needed on this family. | |
325 | ||
326 | For information on the 430 machine instruction set, see @cite{MSP430 | |
77592908 | 327 | User's Manual, document slau049d}, Texas Instrument, Inc. |
b18c562e NC |
328 | |
329 | @node MSP430 Profiling Capability | |
330 | @section Profiling Capability | |
331 | ||
332 | @cindex MSP 430 profiling capability | |
333 | @cindex profiling capability for MSP 430 | |
334 | It is a performance hit to use gcc's profiling approach for this tiny target. | |
335 | Even more -- jtag hardware facility does not perform any profiling functions. | |
336 | However we've got gdb's built-in simulator where we can do anything. | |
337 | ||
338 | We define new section @samp{.profiler} which holds all profiling information. | |
339 | We define new pseudo operation @samp{.profiler} which will instruct assembler to | |
340 | add new profile entry to the object file. Profile should take place at the | |
341 | present address. | |
342 | ||
343 | Pseudo operation format: | |
344 | ||
345 | @samp{.profiler flags,function_to_profile [, cycle_corrector, extra]} | |
346 | ||
347 | ||
348 | where: | |
349 | ||
350 | @table @code | |
351 | ||
352 | @table @code | |
353 | ||
354 | @samp{flags} is a combination of the following characters: | |
355 | ||
34bca508 | 356 | @item s |
b18c562e | 357 | function entry |
34bca508 | 358 | @item x |
b18c562e | 359 | function exit |
34bca508 | 360 | @item i |
b18c562e | 361 | function is in init section |
34bca508 | 362 | @item f |
b18c562e | 363 | function is in fini section |
34bca508 | 364 | @item l |
b18c562e | 365 | library call |
34bca508 | 366 | @item c |
b18c562e | 367 | libc standard call |
34bca508 | 368 | @item d |
b18c562e | 369 | stack value demand |
34bca508 | 370 | @item I |
b18c562e | 371 | interrupt service routine |
34bca508 | 372 | @item P |
b18c562e | 373 | prologue start |
34bca508 | 374 | @item p |
b18c562e | 375 | prologue end |
34bca508 | 376 | @item E |
b18c562e | 377 | epilogue start |
34bca508 | 378 | @item e |
b18c562e | 379 | epilogue end |
34bca508 | 380 | @item j |
b18c562e | 381 | long jump / sjlj unwind |
34bca508 | 382 | @item a |
b18c562e NC |
383 | an arbitrary code fragment |
384 | @item t | |
385 | extra parameter saved (a constant value like frame size) | |
386 | @end table | |
387 | ||
34bca508 | 388 | @item function_to_profile |
b18c562e | 389 | a function address |
34bca508 | 390 | @item cycle_corrector |
b18c562e | 391 | a value which should be added to the cycle counter, zero if omitted. |
34bca508 | 392 | @item extra |
b18c562e NC |
393 | any extra parameter, zero if omitted. |
394 | ||
395 | @end table | |
396 | ||
397 | For example: | |
398 | @smallexample | |
399 | .global fxx | |
400 | .type fxx,@@function | |
401 | fxx: | |
402 | .LFrameOffset_fxx=0x08 | |
403 | .profiler "scdP", fxx ; function entry. | |
404 | ; we also demand stack value to be saved | |
405 | push r11 | |
406 | push r10 | |
407 | push r9 | |
408 | push r8 | |
409 | .profiler "cdpt",fxx,0, .LFrameOffset_fxx ; check stack value at this point | |
410 | ; (this is a prologue end) | |
34bca508 | 411 | ; note, that spare var filled with |
b18c562e NC |
412 | ; the farme size |
413 | mov r15,r8 | |
414 | ... | |
415 | .profiler cdE,fxx ; check stack | |
416 | pop r8 | |
417 | pop r9 | |
418 | pop r10 | |
419 | pop r11 | |
420 | .profiler xcde,fxx,3 ; exit adds 3 to the cycle counter | |
421 | ret ; cause 'ret' insn takes 3 cycles | |
422 | @end smallexample |