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 <b>Arm Compiler Version 5 Toolchain</b> the following \ref intrinsic_CPU_gr are implemented using the Embedded Assembler.
11 As the Embedded Assembler may cause side effects (Refer to <b>Arm Compiler v5.xx User Guide - Using the Inline and Embedded Assemblers of the Arm Compiler</b> for more information)
12 it is possible to disable the following intrinsic functions and therefore the usage of the Embedded Assembler with the <b><i>define __NO_EMBEDDED_ASM</i></b>:
19 /**************************************************************************************************/
20 /** \brief No Operation
22 This function does nothing. This instruction can be used for code alignment purposes.
27 /**************************************************************************************************/
28 /** \brief Wait For Interrupt
30 WFI is a hint instruction that suspends execution until one of the following events occurs:
31 - A non-masked interrupt occurs and is taken.
32 - An interrupt masked by PRIMASK becomes pending.
33 - A Debug Entry request.
38 /**************************************************************************************************/
39 /** \brief Wait For Event
41 Wait For Event is a hint instruction that permits the processor to enter
42 a low-power state until an events occurs:
43 \li If the <b>event register is 0</b>, then WFE suspends execution until one of the following events occurs:
44 - An exception, unless masked by the exception mask registers or the current priority level.
45 - An exception enters the Pending state, if SEVONPEND in the System Control Register is set.
46 - A Debug Entry request, if Debug is enabled.
47 - An event signaled by a peripheral or another processor in a multiprocessor system using
50 \li If the <b>event register is 1</b>, then WFE clears it to 0 and returns immediately.
56 /**************************************************************************************************/
59 Send Event is a hint instruction. It causes an event to be signaled to the CPU.
64 /**************************************************************************************************/
65 /** \brief Set Breakpoint
67 This function causes the processor to enter Debug state.
68 Debug tools can use this to investigate system state when the instruction at a particular address is reached.
70 \param [in] value is ignored by the processor. If required, a debugger can use it to obtain additional information about the breakpoint.
72 void __BKPT(uint8_t value);
75 /**************************************************************************************************/
76 /** \brief Instruction Synchronization Barrier
78 Instruction Synchronization Barrier flushes the pipeline in the processor,
79 so that all instructions following the ISB are fetched from cache or
80 memory, after the instruction has been completed.
85 /**************************************************************************************************/
86 /** \brief Data Synchronization Barrier
89 This function acts as a special kind of Data Memory Barrier.
90 It completes when all explicit memory accesses before this instruction complete.
95 /**************************************************************************************************/
96 /** \brief Data Memory Barrier
99 This function ensures the apparent order of the explicit memory operations before
100 and after the instruction, without ensuring their completion.
105 /**************************************************************************************************/
107 \brief Reverse byte order (32 bit)
108 \details Reverses the byte order in unsigned integer value. For example, 0x12345678 becomes 0x78563412.
109 \param [in] value Value to reverse
110 \return Reversed value
112 uint32_t __REV(uint32_t value);
115 /**************************************************************************************************/
117 \brief Reverse byte order (16 bit)
118 \details Reverses the byte order within each halfword of a word. For example, 0x12345678 becomes 0x34127856.
119 \param [in] value Value to reverse
120 \return Reversed value
122 uint32_t __REV16(uint32_t value);
125 /**************************************************************************************************/
127 \brief Reverse byte order (16 bit)
128 \details Reverses the byte order in a 16-bit value and returns the signed 16-bit result. For example, 0x0080 becomes 0x8000.
129 \param [in] value Value to reverse
130 \return Reversed value
132 int16_t __REVSH(int16_t value);
135 /**************************************************************************************************/
137 \brief Reverse bit order of value
138 \param [in] value Value to reverse
139 \return Reversed value
141 uint32_t __RBIT(uint32_t value);
144 /**************************************************************************************************/
145 /** \brief Rotate a value right by a number of bits
147 This function rotates a value right by a specified number of bits.
149 \param [in] value Value to be shifted right
150 \param [in] shift Number of bits in the range [1..31]
151 \return Rotated value
154 uint32_t __ROR(uint32_t value, uint32_t shift);
157 /**************************************************************************************************/
158 /** \brief LDR Exclusive (8 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
160 This function executed an exclusive LDR command for 8 bit value [not for Cortex-M0, Cortex-M0+, or SC000].
162 \param [in] *addr Pointer to data
163 \return value of type uint8_t at (*addr)
165 uint8_t __LDREXB(volatile uint8_t *addr);
168 /**************************************************************************************************/
169 /** \brief LDR Exclusive (16 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
171 This function executed an exclusive LDR command for 16 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
173 \param [in] *addr Pointer to data
174 \return value of type uint16_t at (*addr)
176 uint16_t __LDREXH(volatile uint16_t *addr);
179 /**************************************************************************************************/
180 /** \brief LDR Exclusive (32 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
182 This function executed an exclusive LDR command for 32 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
184 \param [in] *addr Pointer to data
185 \return value of type uint32_t at (*addr)
187 uint32_t __LDREXW(volatile uint32_t *addr);
190 /**************************************************************************************************/
191 /** \brief STR Exclusive (8 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
193 This function executed an exclusive STR command for 8 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
195 \param [in] value Value to store
196 \param [in] *addr Pointer to location
197 \return 0 Function succeeded
198 \return 1 Function failed
200 uint32_t __STREXB(uint8_t value, volatile uint8_t *addr);
203 /**************************************************************************************************/
204 /** \brief STR Exclusive (16 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
206 This function executed an exclusive STR command for 16 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
208 \param [in] value Value to store
209 \param [in] *addr Pointer to location
210 \return 0 Function succeeded
211 \return 1 Function failed
213 uint32_t __STREXH(uint16_t value, volatile uint16_t *addr);
216 /**************************************************************************************************/
217 /** \brief STR Exclusive (32 bit) [not for Cortex-M0, Cortex-M0+, or SC000]
219 This function executed an exclusive STR command for 32 bit values [not for Cortex-M0, Cortex-M0+, or SC000].
221 \param [in] value Value to store
222 \param [in] *addr Pointer to location
223 \return 0 Function succeeded
224 \return 1 Function failed
226 uint32_t __STREXW(uint32_t value, volatile uint32_t *addr);
229 /**************************************************************************************************/
230 /** \brief Remove the exclusive lock [not for Cortex-M0, Cortex-M0+, or SC000]
232 This function removes the exclusive lock which is created by LDREX [not for Cortex-M0, Cortex-M0+, or SC000].
238 /**************************************************************************************************/
239 /** \brief Signed Saturate [not for Cortex-M0, Cortex-M0+, or SC000]
241 This function saturates a signed value [not for Cortex-M0, Cortex-M0+, or SC000].
243 \param [in] value Value to be saturated
244 \param [in] sat Bit position to saturate to [1..32]
245 \return Saturated value
247 int32_t __SSAT(int32_t value, uint32_t sat);
250 /**************************************************************************************************/
251 /** \brief Unsigned Saturate [not for Cortex-M0, Cortex-M0+, or SC000]
253 This function saturates an unsigned value [not for Cortex-M0, Cortex-M0+, or SC000].
255 \param [in] value Value to be saturated
256 \param [in] sat Bit position to saturate to [0..31]
257 \return Saturated value
259 uint32_t __USAT(uint32_t value, uint32_t sat);
262 /**************************************************************************************************/
263 /** \brief Count leading zeros
265 This function counts the number of leading zeros of a data value.
267 On Armv6-M (Cortex-M0, Cortex-M0+, and SC000) this function is not available as a core instruction
268 instruction and thus __CLZ is implemented in software.
270 \param [in] value Value to count the leading zeros
271 \return number of leading zeros in value
273 uint8_t __CLZ(uint32_t value);
276 /**************************************************************************************************/
277 /** \brief Rotate Right with Extend (32 bit)
279 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.
281 \param [in] value Value to rotate
282 \return Rotated value
284 uint32_t __RRX(uint32_t value);
287 /**************************************************************************************************/
288 /** \brief LDRT Unprivileged (8 bit)
290 This function executed an Unprivileged LDRT command for 8 bit value.
292 \param [in] ptr Pointer to data
293 \return value of type uint8_t at (*ptr)
295 uint8_t __LDRBT(uint8_t ptr);
298 /**************************************************************************************************/
299 /** \brief LDRT Unprivileged (16 bit)
301 This function executed an Unprivileged LDRT command for 16 bit values.
303 \param [in] ptr Pointer to data
304 \return value of type uint16_t at (*ptr)
306 uint16_t __LDRHT(uint16_t ptr);
309 /**************************************************************************************************/
310 /** \brief LDRT Unprivileged (32 bit)
312 This function executed an Unprivileged LDRT command for 32 bit values.
314 \param [in] ptr Pointer to data
315 \return value of type uint32_t at (*ptr)
317 uint32_t __LDRT(uint32_t ptr);
320 /**************************************************************************************************/
321 /** \brief STRT Unprivileged (8 bit)
323 This function executed an Unprivileged STRT command for 8 bit values.
325 \param [in] value Value to store
326 \param [in] ptr Pointer to location
328 void __STRBT(uint8_t value, uint8_t ptr);
331 /**************************************************************************************************/
332 /** \brief STRT Unprivileged (16 bit)
334 This function executed an Unprivileged STRT command for 16 bit values.
336 \param [in] value Value to store
337 \param [in] ptr Pointer to location
339 void __STRHT(uint16_t value, uint16_t ptr);
342 /**************************************************************************************************/
343 /** \brief STRT Unprivileged (32 bit)
345 This function executed an Unprivileged STRT command for 32 bit values.
347 \param [in] value Value to store
348 \param [in] ptr Pointer to location
350 void __STRT(uint32_t value, uint32_t ptr);
358 \brief Load-Acquire (8 bit)
359 \details Executes a LDAB instruction for 8 bit value.
360 \param [in] ptr Pointer to data
361 \return value of type uint8_t at (*ptr)
362 \note Only availabe for Armv8-M Architecture.
364 uint8_t __LDAB(volatile uint8_t *ptr);
367 \brief Load-Acquire (16 bit)
368 \details Executes a LDAH instruction for 16 bit values.
369 \param [in] ptr Pointer to data
370 \return value of type uint16_t at (*ptr)
371 \note Only availabe for Armv8-M Architecture.
373 uint16_t __LDAH(volatile uint16_t *ptr);
376 \brief Load-Acquire (32 bit)
377 \details Executes a LDA instruction for 32 bit values.
378 \param [in] ptr Pointer to data
379 \return value of type uint32_t at (*ptr)
380 \note Only availabe for Armv8-M Architecture.
382 uint32_t __LDA(volatile uint32_t *ptr);
385 \brief Store-Release (8 bit)
386 \details Executes a STLB instruction for 8 bit values.
387 \param [in] value Value to store
388 \param [in] ptr Pointer to location
389 \note Only availabe for Armv8-M Architecture.
391 void __STLB(uint8_t value, volatile uint8_t *ptr);
394 \brief Store-Release (16 bit)
395 \details Executes a STLH instruction for 16 bit values.
396 \param [in] value Value to store
397 \param [in] ptr Pointer to location
398 \note Only availabe for Armv8-M Architecture.
400 void __STLH(uint16_t value, volatile uint16_t *ptr);
403 \brief Store-Release (32 bit)
404 \details Executes a STL instruction for 32 bit values.
405 \param [in] value Value to store
406 \param [in] ptr Pointer to location
407 \note Only availabe for Armv8-M Architecture.
409 void __STL(uint32_t value, volatile uint32_t *ptr);
412 \brief Load-Acquire Exclusive (8 bit)
413 \details Executes a LDAB exclusive instruction for 8 bit value.
414 \param [in] ptr Pointer to data
415 \return value of type uint8_t at (*ptr)
416 \note Only availabe for Armv8-M Architecture.
418 uint8_t __LDAEXB(volatile uint32_t *ptr);
421 \brief Load-Acquire Exclusive (16 bit)
422 \details Executes a LDAH exclusive instruction for 16 bit values.
423 \param [in] ptr Pointer to data
424 \return value of type uint16_t at (*ptr)
425 \note Only availabe for Armv8-M Architecture.
427 uint16_t __LDAEXH(volatile uint32_t *ptr);
430 \brief Load-Acquire Exclusive (32 bit)
431 \details Executes a LDA exclusive instruction for 32 bit values.
432 \param [in] ptr Pointer to data
433 \return value of type uint32_t at (*ptr)
434 \note Only availabe for Armv8-M Architecture.
436 uint32_t __LDAEX(volatile uint32_t *ptr);
439 \brief Store-Release Exclusive (8 bit)
440 \details Executes a STLB exclusive instruction for 8 bit values.
441 \param [in] value Value to store
442 \param [in] ptr Pointer to location
443 \return 0 Function succeeded
444 \return 1 Function failed
445 \note Only availabe for Armv8-M Architecture.
447 uint32_t __STLEXB(uint8_t value, volatile uint8_t *ptr);
450 \brief Store-Release Exclusive (16 bit)
451 \details Executes a STLH exclusive instruction for 16 bit values.
452 \param [in] value Value to store
453 \param [in] ptr Pointer to location
454 \return 0 Function succeeded
455 \return 1 Function failed
456 \note Only availabe for Armv8-M Architecture.
458 uint32_t __STLEXH(uint16_t value, volatile uint16_t *ptr);
461 \brief Store-Release Exclusive (32 bit)
462 \details Executes a STL exclusive instruction for 32 bit values.
463 \param [in] value Value to store
464 \param [in] ptr Pointer to location
465 \return 0 Function succeeded
466 \return 1 Function failed
467 \note Only availabe for Armv8-M Architecture.
469 uint32_t __STLEX(uint32_t value, volatile uint32_t *ptr);
475 /*@}*/ /* end of group Intrisic_CPU */