2 \defgroup intrinsic_CPU_gr Intrinsic Functions for CPU Instructions
4 \brief Functions that generate specific Cortex-M CPU Instructions.
6 The following functions generate specific Cortex-M instructions that cannot be directly accessed by the C/C++ Compiler.
7 Refer to the \ref ref_man_sec for detailed information about these Cortex-M instructions.
10 When using the Arm Compiler Toolchain the following \ref intrinsic_CPU_gr are implemented using the Embedded Assembler: \ref __RRX, <Bruno: add more...>.
11 The usage of the Embedded Assembler can be disabled by with <b><i>define __NO_EMBEDDED_ASM</i></b>. This avoids potential side effects of the Embedded Assembler.
12 Refer to <b>Compiler User Guide - Using the Inline and Embedded Assemblers of the Arm Compiler</b> for more information.
15 /**************************************************************************************************/
16 /** \brief No Operation
18 This function does nothing. This instruction can be used for code alignment purposes.
23 /**************************************************************************************************/
24 /** \brief Wait For Interrupt
26 WFI is a hint instruction that suspends execution until one of the following events occurs:
27 - A non-masked interrupt occurs and is taken.
28 - An interrupt masked by PRIMASK becomes pending.
29 - A Debug Entry request.
34 /**************************************************************************************************/
35 /** \brief Wait For Event
37 Wait For Event is a hint instruction that permits the processor to enter
38 a low-power state until an events occurs:
39 \li If the <b>event register is 0</b>, then WFE suspends execution until one of the following events occurs:
40 - An exception, unless masked by the exception mask registers or the current priority level.
41 - An exception enters the Pending state, if SEVONPEND in the System Control Register is set.
42 - A Debug Entry request, if Debug is enabled.
43 - An event signaled by a peripheral or another processor in a multiprocessor system using
46 \li If the <b>event register is 1</b>, then WFE clears it to 0 and returns immediately.
52 /**************************************************************************************************/
55 Send Event is a hint instruction. It causes an event to be signaled to the CPU.
60 /**************************************************************************************************/
61 /** \brief Set Breakpoint
63 This function causes the processor to enter Debug state.
64 Debug tools can use this to investigate system state when the instruction at a particular address is reached.
66 \param [in] value is ignored by the processor. If required, a debugger can use it to obtain additional information about the breakpoint.
68 void __BKPT(uint8_t value);
71 /**************************************************************************************************/
72 /** \brief Instruction Synchronization Barrier
74 Instruction Synchronization Barrier flushes the pipeline in the processor,
75 so that all instructions following the ISB are fetched from cache or
76 memory, after the instruction has been completed.
81 /**************************************************************************************************/
82 /** \brief Data Synchronization Barrier
85 This function acts as a special kind of Data Memory Barrier.
86 It completes when all explicit memory accesses before this instruction complete.
91 /**************************************************************************************************/
92 /** \brief Data Memory Barrier
95 This function ensures the apparent order of the explicit memory operations before
96 and after the instruction, without ensuring their completion.
101 /**************************************************************************************************/
103 \brief Reverse byte order (32 bit)
104 \details Reverses the byte order in unsigned integer value. For example, 0x12345678 becomes 0x78563412.
105 \param [in] value Value to reverse
106 \return Reversed value
108 uint32_t __REV(uint32_t value);
111 /**************************************************************************************************/
113 \brief Reverse byte order (16 bit)
114 \details Reverses the byte order within each halfword of a word. For example, 0x12345678 becomes 0x34127856.
115 \param [in] value Value to reverse
116 \return Reversed value
118 uint32_t __REV16(uint32_t value);
121 /**************************************************************************************************/
123 \brief Reverse byte order (16 bit)
124 \details Reverses the byte order in a 16-bit value and returns the signed 16-bit result. For example, 0x0080 becomes 0x8000.
125 \param [in] value Value to reverse
126 \return Reversed value
128 int32_t __REVSH(int32_t value);
131 /**************************************************************************************************/
133 \brief Reverse bit order of value
134 \param [in] value Value to reverse
135 \return Reversed value
137 uint32_t __RBIT(uint32_t value);
140 /**************************************************************************************************/
141 /** \brief Rotate a value right by a number of bits
143 This function rotates a value right by a specified number of bits.
145 \param [in] value Value to be shifted right
146 \param [in] shift Number of bits in the range [1..31]
147 \return Rotated value
150 uint32_t __ROR(uint32_t value, uint32_t shift);
153 /**************************************************************************************************/
154 /** \brief LDR Exclusive (8 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
156 This function executed an exclusive LDR command for 8 bit value [not for Cortex-M0, Cortex-M0+, or SC000].
158 \param [in] *addr Pointer to data
159 \return value of type uint8_t at (*addr)
161 uint8_t __LDREXB(volatile uint8_t *addr);
164 /**************************************************************************************************/
165 /** \brief LDR Exclusive (16 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
167 This function executed an exclusive LDR command for 16 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
169 \param [in] *addr Pointer to data
170 \return value of type uint16_t at (*addr)
172 uint16_t __LDREXH(volatile uint16_t *addr);
175 /**************************************************************************************************/
176 /** \brief LDR Exclusive (32 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
178 This function executed an exclusive LDR command for 32 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
180 \param [in] *addr Pointer to data
181 \return value of type uint32_t at (*addr)
183 uint32_t __LDREXW(volatile uint32_t *addr);
186 /**************************************************************************************************/
187 /** \brief STR Exclusive (8 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
189 This function executed an exclusive STR command for 8 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
191 \param [in] value Value to store
192 \param [in] *addr Pointer to location
193 \return 0 Function succeeded
194 \return 1 Function failed
196 uint32_t __STREXB(uint8_t value, volatile uint8_t *addr);
199 /**************************************************************************************************/
200 /** \brief STR Exclusive (16 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
202 This function executed an exclusive STR command for 16 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
204 \param [in] value Value to store
205 \param [in] *addr Pointer to location
206 \return 0 Function succeeded
207 \return 1 Function failed
209 uint32_t __STREXH(uint16_t value, volatile uint16_t *addr);
212 /**************************************************************************************************/
213 /** \brief STR Exclusive (32 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
215 This function executed an exclusive STR command for 32 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
217 \param [in] value Value to store
218 \param [in] *addr Pointer to location
219 \return 0 Function succeeded
220 \return 1 Function failed
222 uint32_t __STREXW(uint32_t value, volatile uint32_t *addr);
225 /**************************************************************************************************/
226 /** \brief Remove the exclusive lock [not for Cortex-M0, Cortex-M0+, or SC000]
228 This function removes the exclusive lock which is created by LDREX [not for Cortex-M0, Cortex-M0+, or SC000].
234 /**************************************************************************************************/
235 /** \brief Signed Saturate [not for Cortex-M0, Cortex-M0+, or SC000]
237 This function saturates a signed value [not for Cortex-M0, Cortex-M0+, or SC000].
239 \param [in] value Value to be saturated
240 \param [in] sat Bit position to saturate to [1..32]
241 \return Saturated value
243 int32_t __SSAT(int32_t value, uint32_t sat);
246 /**************************************************************************************************/
247 /** \brief Unsigned Saturate [not for Cortex-M0, Cortex-M0+, or SC000]
249 This function saturates an unsigned value [not for Cortex-M0, Cortex-M0+, or SC000].
251 \param [in] value Value to be saturated
252 \param [in] sat Bit position to saturate to [0..31]
253 \return Saturated value
255 uint32_t __USAT(uint32_t value, uint32_t sat);
258 /**************************************************************************************************/
259 /** \brief Count leading zeros
261 This function counts the number of leading zeros of a data value.
263 On Armv6-M (Cortex-M0, Cortex-M0+, and SC000) this function is not available as a core instruction
264 instruction and thus __CLZ is implemented in software.
266 \param [in] value Value to count the leading zeros
267 \return number of leading zeros in value
269 uint8_t __CLZ(uint32_t value);
272 /**************************************************************************************************/
273 /** \brief Rotate Right with Extend (32 bit)
275 This function moves each bit of a bitstring right by one bit. The carry input is shifted in at the left end of the bitstring.
277 \param [in] value Value to rotate
278 \return Rotated value
280 uint32_t __RRX(uint32_t value);
283 /**************************************************************************************************/
284 /** \brief LDRT Unprivileged (8 bit)
286 This function executed an Unprivileged LDRT command for 8 bit value.
288 \param [in] ptr Pointer to data
289 \return value of type uint8_t at (*ptr)
291 uint8_t __LDRBT(uint8_t ptr);
294 /**************************************************************************************************/
295 /** \brief LDRT Unprivileged (16 bit)
297 This function executed an Unprivileged LDRT command for 16 bit values.
299 \param [in] ptr Pointer to data
300 \return value of type uint16_t at (*ptr)
302 uint16_t __LDRHT(uint16_t ptr);
305 /**************************************************************************************************/
306 /** \brief LDRT Unprivileged (32 bit)
308 This function executed an Unprivileged LDRT command for 32 bit values.
310 \param [in] ptr Pointer to data
311 \return value of type uint32_t at (*ptr)
313 uint32_t __LDRT(uint32_t ptr);
316 /**************************************************************************************************/
317 /** \brief STRT Unprivileged (8 bit)
319 This function executed an Unprivileged STRT command for 8 bit values.
321 \param [in] value Value to store
322 \param [in] ptr Pointer to location
324 void __STRBT(uint8_t value, uint8_t ptr);
327 /**************************************************************************************************/
328 /** \brief STRT Unprivileged (16 bit)
330 This function executed an Unprivileged STRT command for 16 bit values.
332 \param [in] value Value to store
333 \param [in] ptr Pointer to location
335 void __STRHT(uint16_t value, uint16_t ptr);
338 /**************************************************************************************************/
339 /** \brief STRT Unprivileged (32 bit)
341 This function executed an Unprivileged STRT command for 32 bit values.
343 \param [in] value Value to store
344 \param [in] ptr Pointer to location
346 void __STRT(uint32_t value, uint32_t ptr);
351 \brief Load-Acquire (8 bit)
352 \details Executes a LDAB instruction for 8 bit value.
353 \param [in] ptr Pointer to data
354 \return value of type uint8_t at (*ptr)
355 \note Only availabe for Armv8-M Architecture.
357 uint8_t __LDAB(volatile uint8_t *ptr);
360 \brief Load-Acquire (16 bit)
361 \details Executes a LDAH instruction for 16 bit values.
362 \param [in] ptr Pointer to data
363 \return value of type uint16_t at (*ptr)
364 \note Only availabe for Armv8-M Architecture.
366 uint16_t __LDAH(volatile uint16_t *ptr);
369 \brief Load-Acquire (32 bit)
370 \details Executes a LDA instruction for 32 bit values.
371 \param [in] ptr Pointer to data
372 \return value of type uint32_t at (*ptr)
373 \note Only availabe for Armv8-M Architecture.
375 uint32_t __LDA(volatile uint32_t *ptr);
378 \brief Store-Release (8 bit)
379 \details Executes a STLB instruction for 8 bit values.
380 \param [in] value Value to store
381 \param [in] ptr Pointer to location
382 \note Only availabe for Armv8-M Architecture.
384 void __STLB(uint8_t value, volatile uint8_t *ptr);
387 \brief Store-Release (16 bit)
388 \details Executes a STLH instruction for 16 bit values.
389 \param [in] value Value to store
390 \param [in] ptr Pointer to location
391 \note Only availabe for Armv8-M Architecture.
393 void __STLH(uint16_t value, volatile uint16_t *ptr);
396 \brief Store-Release (32 bit)
397 \details Executes a STL instruction for 32 bit values.
398 \param [in] value Value to store
399 \param [in] ptr Pointer to location
400 \note Only availabe for Armv8-M Architecture.
402 void __STL(uint32_t value, volatile uint32_t *ptr);
405 \brief Load-Acquire Exclusive (8 bit)
406 \details Executes a LDAB exclusive instruction for 8 bit value.
407 \param [in] ptr Pointer to data
408 \return value of type uint8_t at (*ptr)
409 \note Only availabe for Armv8-M Architecture.
411 uint8_t __LDAEXB(volatile uint32_t *ptr);
414 \brief Load-Acquire Exclusive (16 bit)
415 \details Executes a LDAH exclusive instruction for 16 bit values.
416 \param [in] ptr Pointer to data
417 \return value of type uint16_t at (*ptr)
418 \note Only availabe for Armv8-M Architecture.
420 uint16_t __LDAEXH(volatile uint32_t *ptr);
423 \brief Load-Acquire Exclusive (32 bit)
424 \details Executes a LDA exclusive instruction for 32 bit values.
425 \param [in] ptr Pointer to data
426 \return value of type uint32_t at (*ptr)
427 \note Only availabe for Armv8-M Architecture.
429 uint32_t __LDAEX(volatile uint32_t *ptr);
432 \brief Store-Release Exclusive (8 bit)
433 \details Executes a STLB exclusive instruction for 8 bit values.
434 \param [in] value Value to store
435 \param [in] ptr Pointer to location
436 \return 0 Function succeeded
437 \return 1 Function failed
438 \note Only availabe for Armv8-M Architecture.
440 uint32_t __STLEXB(uint8_t value, volatile uint8_t *ptr);
443 \brief Store-Release Exclusive (16 bit)
444 \details Executes a STLH exclusive instruction for 16 bit values.
445 \param [in] value Value to store
446 \param [in] ptr Pointer to location
447 \return 0 Function succeeded
448 \return 1 Function failed
449 \note Only availabe for Armv8-M Architecture.
451 uint32_t __STLEXH(uint16_t value, volatile uint16_t *ptr);
454 \brief Store-Release Exclusive (32 bit)
455 \details Executes a STL exclusive instruction for 32 bit values.
456 \param [in] value Value to store
457 \param [in] ptr Pointer to location
458 \return 0 Function succeeded
459 \return 1 Function failed
460 \note Only availabe for Armv8-M Architecture.
462 uint32_t __STLEX(uint32_t value, volatile uint32_t *ptr);
465 /*@}*/ /* end of group Intrisic_CPU */