Zephyr API Documentation  3.6.99
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gcc.h
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1/*
2 * Copyright (c) 2010-2014,2017 Wind River Systems, Inc.
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7#ifndef ZEPHYR_INCLUDE_TOOLCHAIN_GCC_H_
8#define ZEPHYR_INCLUDE_TOOLCHAIN_GCC_H_
9
10#ifndef ZEPHYR_INCLUDE_TOOLCHAIN_H_
11#error Please do not include toolchain-specific headers directly, use <zephyr/toolchain.h> instead
12#endif
13
21#define TOOLCHAIN_GCC_VERSION \
22 ((__GNUC__ * 10000) + (__GNUC_MINOR__ * 100) + __GNUC_PATCHLEVEL__)
23
24/* GCC supports #pragma diagnostics since 4.6.0 */
25#if !defined(TOOLCHAIN_HAS_PRAGMA_DIAG) && (TOOLCHAIN_GCC_VERSION >= 40600)
26#define TOOLCHAIN_HAS_PRAGMA_DIAG 1
27#endif
28
29#if !defined(TOOLCHAIN_HAS_C_GENERIC) && (TOOLCHAIN_GCC_VERSION >= 40900)
30#define TOOLCHAIN_HAS_C_GENERIC 1
31#endif
32
33#if !defined(TOOLCHAIN_HAS_C_AUTO_TYPE) && (TOOLCHAIN_GCC_VERSION >= 40900)
34#define TOOLCHAIN_HAS_C_AUTO_TYPE 1
35#endif
36
37#define TOOLCHAIN_HAS_ZLA 1
38
39/*
40 * Older versions of GCC do not define __BYTE_ORDER__, so it must be manually
41 * detected and defined using arch-specific definitions.
42 */
43
44#ifndef _LINKER
45
46#ifndef __ORDER_BIG_ENDIAN__
47#define __ORDER_BIG_ENDIAN__ (1)
48#endif
49
50#ifndef __ORDER_LITTLE_ENDIAN__
51#define __ORDER_LITTLE_ENDIAN__ (2)
52#endif
53
54#ifndef __BYTE_ORDER__
55#if defined(__BIG_ENDIAN__) || defined(__ARMEB__) || \
56 defined(__THUMBEB__) || defined(__AARCH64EB__) || \
57 defined(__MIPSEB__) || defined(__TC32EB__)
58
59#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
60
61#elif defined(__LITTLE_ENDIAN__) || defined(__ARMEL__) || \
62 defined(__THUMBEL__) || defined(__AARCH64EL__) || \
63 defined(__MIPSEL__) || defined(__TC32EL__)
64
65#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
66
67#else
68#error "__BYTE_ORDER__ is not defined and cannot be automatically resolved"
69#endif
70#endif
71
72
73#undef BUILD_ASSERT /* clear out common version */
74/* C++11 has static_assert built in */
75#if defined(__cplusplus) && (__cplusplus >= 201103L)
76#define BUILD_ASSERT(EXPR, MSG...) static_assert(EXPR, "" MSG)
77
78/*
79 * GCC 4.6 and higher have the C11 _Static_assert built in and its
80 * output is easier to understand than the common BUILD_ASSERT macros.
81 * Don't use this in C++98 mode though (which we can hit, as
82 * static_assert() is not available)
83 */
84#elif !defined(__cplusplus) && \
85 (((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6))) || \
86 (__STDC_VERSION__) >= 201100)
87#define BUILD_ASSERT(EXPR, MSG...) _Static_assert(EXPR, "" MSG)
88#else
89#define BUILD_ASSERT(EXPR, MSG...)
90#endif
91
92#ifdef __cplusplus
93#define ZRESTRICT __restrict
94#else
95#define ZRESTRICT restrict
96#endif
97
99#include <stdbool.h>
100
101#define ALIAS_OF(of) __attribute__((alias(#of)))
102
103#define FUNC_ALIAS(real_func, new_alias, return_type) \
104 return_type new_alias() ALIAS_OF(real_func)
105
106#if defined(CONFIG_ARCH_POSIX) && !defined(_ASMLANGUAGE)
108
109/*let's not segfault if this were to happen for some reason*/
110#define CODE_UNREACHABLE \
111{\
112 posix_print_error_and_exit("CODE_UNREACHABLE reached from %s:%d\n",\
113 __FILE__, __LINE__);\
114 __builtin_unreachable(); \
115}
116#else
117#define CODE_UNREACHABLE __builtin_unreachable()
118#endif
119#define FUNC_NORETURN __attribute__((__noreturn__))
120
121/* The GNU assembler for Cortex-M3 uses # for immediate values, not
122 * comments, so the @nobits# trick does not work.
123 */
124#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
125#define _NODATA_SECTION(segment) __attribute__((section(#segment)))
126#else
127#define _NODATA_SECTION(segment) \
128 __attribute__((section(#segment ",\"wa\",@nobits#")))
129#endif
130
131/* Unaligned access */
132#define UNALIGNED_GET(g) \
133__extension__ ({ \
134 struct __attribute__((__packed__)) { \
135 __typeof__(*(g)) __v; \
136 } *__g = (__typeof__(__g)) (g); \
137 __g->__v; \
138})
139
140
141#if (__GNUC__ >= 7) && (defined(CONFIG_ARM) || defined(CONFIG_ARM64))
142
143/* Version of UNALIGNED_PUT() which issues a compiler_barrier() after
144 * the store. It is required to workaround an apparent optimization
145 * bug in GCC for ARM Cortex-M3 and higher targets, when multiple
146 * byte, half-word and word stores (strb, strh, str instructions),
147 * which support unaligned access, can be coalesced into store double
148 * (strd) instruction, which doesn't support unaligned access (the
149 * compilers in question do this optimization ignoring __packed__
150 * attribute).
151 */
152#define UNALIGNED_PUT(v, p) \
153do { \
154 struct __attribute__((__packed__)) { \
155 __typeof__(*p) __v; \
156 } *__p = (__typeof__(__p)) (p); \
157 __p->__v = (v); \
158 compiler_barrier(); \
159} while (false)
160
161#else
162
163#define UNALIGNED_PUT(v, p) \
164do { \
165 struct __attribute__((__packed__)) { \
166 __typeof__(*p) __v; \
167 } *__p = (__typeof__(__p)) (p); \
168 __p->__v = (v); \
169} while (false)
170
171#endif
172
173/* Double indirection to ensure section names are expanded before
174 * stringification
175 */
176#define __GENERIC_SECTION(segment) __attribute__((section(STRINGIFY(segment))))
177#define Z_GENERIC_SECTION(segment) __GENERIC_SECTION(segment)
178
179#define __GENERIC_DOT_SECTION(segment) \
180 __attribute__((section("." STRINGIFY(segment))))
181#define Z_GENERIC_DOT_SECTION(segment) __GENERIC_DOT_SECTION(segment)
182
183#define ___in_section(a, b, c) \
184 __attribute__((section("." Z_STRINGIFY(a) \
185 "." Z_STRINGIFY(b) \
186 "." Z_STRINGIFY(c))))
187#define __in_section(a, b, c) ___in_section(a, b, c)
188
189#define __in_section_unique(seg) ___in_section(seg, __FILE__, __COUNTER__)
190
191#define __in_section_unique_named(seg, name) \
192 ___in_section(seg, __FILE__, name)
193
194/* When using XIP, using '__ramfunc' places a function into RAM instead
195 * of FLASH. Make sure '__ramfunc' is defined only when
196 * CONFIG_ARCH_HAS_RAMFUNC_SUPPORT is defined, so that the compiler can
197 * report an error if '__ramfunc' is used but the architecture does not
198 * support it.
199 */
200#if !defined(CONFIG_XIP)
201#define __ramfunc
202#elif defined(CONFIG_ARCH_HAS_RAMFUNC_SUPPORT)
203#if defined(CONFIG_ARM)
204#define __ramfunc __attribute__((noinline)) \
205 __attribute__((long_call, section(".ramfunc")))
206#else
207#define __ramfunc __attribute__((noinline)) \
208 __attribute__((section(".ramfunc")))
209#endif
210#endif /* !CONFIG_XIP */
211
212#ifndef __fallthrough
213#if __GNUC__ >= 7
214#define __fallthrough __attribute__((fallthrough))
215#else
216#define __fallthrough
217#endif /* __GNUC__ >= 7 */
218#endif
219
220#ifndef __packed
221#define __packed __attribute__((__packed__))
222#endif
223
224#ifndef __aligned
225#define __aligned(x) __attribute__((__aligned__(x)))
226#endif
227
228#define __may_alias __attribute__((__may_alias__))
229
230#ifndef __printf_like
231#ifdef CONFIG_ENFORCE_ZEPHYR_STDINT
232#define __printf_like(f, a) __attribute__((format (printf, f, a)))
233#else
234/*
235 * The Zephyr stdint convention enforces int32_t = int, int64_t = long long,
236 * and intptr_t = long so that short string format length modifiers can be
237 * used universally across ILP32 and LP64 architectures. Without that it
238 * is possible for ILP32 toolchains to have int32_t = long and intptr_t = int
239 * clashing with the Zephyr convention and generating pointless warnings
240 * as they're still the same size. Inhibit the format argument type
241 * validation in that case and let the other configs do it.
242 */
243#define __printf_like(f, a)
244#endif
245#endif
246
247#define __used __attribute__((__used__))
248#define __unused __attribute__((__unused__))
249#define __maybe_unused __attribute__((__unused__))
250
251#ifndef __deprecated
252#define __deprecated __attribute__((deprecated))
253#endif
254
255#ifndef __attribute_const__
256#define __attribute_const__ __attribute__((__const__))
257#endif
258
259#ifndef __must_check
260#define __must_check __attribute__((warn_unused_result))
261#endif
262
263#define ARG_UNUSED(x) (void)(x)
264
265#define likely(x) (__builtin_expect((bool)!!(x), true) != 0L)
266#define unlikely(x) (__builtin_expect((bool)!!(x), false) != 0L)
267#define POPCOUNT(x) __builtin_popcount(x)
268
269#ifndef __no_optimization
270#define __no_optimization __attribute__((optimize("-O0")))
271#endif
272
273#ifndef __weak
274#define __weak __attribute__((__weak__))
275#endif
276
277#ifndef __attribute_nonnull
278#define __attribute_nonnull(...) __attribute__((nonnull(__VA_ARGS__)))
279#endif
280
281/* Builtins with availability that depend on the compiler version. */
282#if __GNUC__ >= 5
283#define HAS_BUILTIN___builtin_add_overflow 1
284#define HAS_BUILTIN___builtin_sub_overflow 1
285#define HAS_BUILTIN___builtin_mul_overflow 1
286#define HAS_BUILTIN___builtin_div_overflow 1
287#endif
288#if __GNUC__ >= 4
289#define HAS_BUILTIN___builtin_clz 1
290#define HAS_BUILTIN___builtin_clzl 1
291#define HAS_BUILTIN___builtin_clzll 1
292#define HAS_BUILTIN___builtin_ctz 1
293#define HAS_BUILTIN___builtin_ctzl 1
294#define HAS_BUILTIN___builtin_ctzll 1
295#endif
296
297/*
298 * Be *very* careful with these. You cannot filter out __DEPRECATED_MACRO with
299 * -wno-deprecated, which has implications for -Werror.
300 */
301
302/*
303 * Expands to nothing and generates a warning. Used like
304 *
305 * #define FOO __WARN("Please use BAR instead") ...
306 *
307 * The warning points to the location where the macro is expanded.
308 */
309#define __WARN(msg) __WARN1(GCC warning msg)
310#define __WARN1(s) _Pragma(#s)
311
312/* Generic message */
313#ifndef __DEPRECATED_MACRO
314#define __DEPRECATED_MACRO __WARN("Macro is deprecated")
315#endif
316
317/* These macros allow having ARM asm functions callable from thumb */
318
319#if defined(_ASMLANGUAGE)
320
321#if defined(CONFIG_ARM)
322
323#if defined(CONFIG_ASSEMBLER_ISA_THUMB2)
324
325#define FUNC_CODE() .thumb;
326#define FUNC_INSTR(a)
327
328#else
329
330#define FUNC_CODE() .code 32;
331#define FUNC_INSTR(a)
332
333#endif /* CONFIG_ASSEMBLER_ISA_THUMB2 */
334
335#else
336
337#define FUNC_CODE()
338#define FUNC_INSTR(a)
339
340#endif /* CONFIG_ARM */
341
342#endif /* _ASMLANGUAGE */
343
344/*
345 * These macros are used to declare assembly language symbols that need
346 * to be typed properly(func or data) to be visible to the OMF tool.
347 * So that the build tool could mark them as an entry point to be linked
348 * correctly. This is an elfism. Use #if 0 for a.out.
349 */
350
351#if defined(_ASMLANGUAGE)
352
353#if defined(CONFIG_ARM) || defined(CONFIG_NIOS2) || defined(CONFIG_RISCV) \
354 || defined(CONFIG_XTENSA) || defined(CONFIG_ARM64) \
355 || defined(CONFIG_MIPS)
356#define GTEXT(sym) .global sym; .type sym, %function
357#define GDATA(sym) .global sym; .type sym, %object
358#define WTEXT(sym) .weak sym; .type sym, %function
359#define WDATA(sym) .weak sym; .type sym, %object
360#elif defined(CONFIG_ARC)
361/*
362 * Need to use assembly macros because ';' is interpreted as the start of
363 * a single line comment in the ARC assembler.
364 */
365
366.macro glbl_text symbol
367 .globl \symbol
368 .type \symbol, %function
369.endm
370
371.macro glbl_data symbol
372 .globl \symbol
373 .type \symbol, %object
374.endm
375
376.macro weak_data symbol
377 .weak \symbol
378 .type \symbol, %object
379.endm
380
381#define GTEXT(sym) glbl_text sym
382#define GDATA(sym) glbl_data sym
383#define WDATA(sym) weak_data sym
384
385#else /* !CONFIG_ARM && !CONFIG_ARC */
386#define GTEXT(sym) .globl sym; .type sym, @function
387#define GDATA(sym) .globl sym; .type sym, @object
388#endif
389
390/*
391 * These macros specify the section in which a given function or variable
392 * resides.
393 *
394 * - SECTION_FUNC allows only one function to reside in a sub-section
395 * - SECTION_SUBSEC_FUNC allows multiple functions to reside in a sub-section
396 * This ensures that garbage collection only discards the section
397 * if all functions in the sub-section are not referenced.
398 */
399
400#if defined(CONFIG_ARC)
401/*
402 * Need to use assembly macros because ';' is interpreted as the start of
403 * a single line comment in the ARC assembler.
404 *
405 * Also, '\‍()' is needed in the .section directive of these macros for
406 * correct substitution of the 'section' variable.
407 */
408
409.macro section_var section, symbol
410 .section .\section\‍().\symbol
411 \symbol :
412.endm
413
414.macro section_func section, symbol
415 .section .\section\().\symbol, "ax"
416 FUNC_CODE()
417 PERFOPT_ALIGN
418 \symbol :
419 FUNC_INSTR(\symbol)
420.endm
421
422.macro section_subsec_func section, subsection, symbol
423 .section .\section\().\subsection, "ax"
424 PERFOPT_ALIGN
425 \symbol :
426.endm
427
428#define SECTION_VAR(sect, sym) section_var sect, sym
429#define SECTION_FUNC(sect, sym) section_func sect, sym
430#define SECTION_SUBSEC_FUNC(sect, subsec, sym) \
431 section_subsec_func sect, subsec, sym
432#else /* !CONFIG_ARC */
433
434#define SECTION_VAR(sect, sym) .section .sect.sym; sym:
435#define SECTION_FUNC(sect, sym) \
436 .section .sect.sym, "ax"; \
437 FUNC_CODE() \
438 PERFOPT_ALIGN; sym : \
439 FUNC_INSTR(sym)
440#define SECTION_SUBSEC_FUNC(sect, subsec, sym) \
441 .section .sect.subsec, "ax"; PERFOPT_ALIGN; sym :
442
443#endif /* CONFIG_ARC */
444
445#endif /* _ASMLANGUAGE */
446
447#if defined(_ASMLANGUAGE)
448#if defined(CONFIG_ARM)
449#if defined(CONFIG_ASSEMBLER_ISA_THUMB2)
450/* '.syntax unified' is a gcc-ism used in thumb-2 asm files */
451#define _ASM_FILE_PROLOGUE .text; .syntax unified; .thumb
452#else
453#define _ASM_FILE_PROLOGUE .text; .code 32
454#endif /* CONFIG_ASSEMBLER_ISA_THUMB2 */
455#elif defined(CONFIG_ARM64)
456#define _ASM_FILE_PROLOGUE .text
457#endif /* CONFIG_ARM64 || CONFIG_ARM */
458#endif /* _ASMLANGUAGE */
459
460/*
461 * These macros generate absolute symbols for GCC
462 */
463
464/* create an extern reference to the absolute symbol */
465
466#define GEN_OFFSET_EXTERN(name) extern const char name[]
467
468#define GEN_ABS_SYM_BEGIN(name) \
469 EXTERN_C void name(void); \
470 void name(void) \
471 {
472
473#define GEN_ABS_SYM_END }
474
475/*
476 * Note that GEN_ABSOLUTE_SYM(), depending on the architecture
477 * and toolchain, may restrict the range of values permitted
478 * for assignment to the named symbol.
479 *
480 * For example, on x86, "value" is interpreted as signed
481 * 32-bit integer. Passing in an unsigned 32-bit integer
482 * with MSB set would result in a negative integer.
483 * Moreover, GCC would error out if an integer larger
484 * than 2^32-1 is passed as "value".
485 */
486
487/*
488 * GEN_ABSOLUTE_SYM_KCONFIG() is outputted by the build system
489 * to generate named symbol/value pairs for kconfigs.
490 */
491
492#if defined(CONFIG_ARM)
493
494/*
495 * GNU/ARM backend does not have a proper operand modifier which does not
496 * produces prefix # followed by value, such as %0 for PowerPC, Intel, and
497 * MIPS. The workaround performed here is using %B0 which converts
498 * the value to ~(value). Thus "n"(~(value)) is set in operand constraint
499 * to output (value) in the ARM specific GEN_OFFSET macro.
500 */
501
502#define GEN_ABSOLUTE_SYM(name, value) \
503 __asm__(".globl\t" #name "\n\t.equ\t" #name \
504 ",%B0" \
505 "\n\t.type\t" #name ",%%object" : : "n"(~(value)))
506
507#define GEN_ABSOLUTE_SYM_KCONFIG(name, value) \
508 __asm__(".globl\t" #name \
509 "\n\t.equ\t" #name "," #value \
510 "\n\t.type\t" #name ",%object")
511
512#elif defined(CONFIG_X86)
513
514#define GEN_ABSOLUTE_SYM(name, value) \
515 __asm__(".globl\t" #name "\n\t.equ\t" #name \
516 ",%c0" \
517 "\n\t.type\t" #name ",@object" : : "n"(value))
518
519#define GEN_ABSOLUTE_SYM_KCONFIG(name, value) \
520 __asm__(".globl\t" #name \
521 "\n\t.equ\t" #name "," #value \
522 "\n\t.type\t" #name ",@object")
523
524#elif defined(CONFIG_ARC) || defined(CONFIG_ARM64)
525
526#define GEN_ABSOLUTE_SYM(name, value) \
527 __asm__(".globl\t" #name "\n\t.equ\t" #name \
528 ",%c0" \
529 "\n\t.type\t" #name ",@object" : : "n"(value))
530
531#define GEN_ABSOLUTE_SYM_KCONFIG(name, value) \
532 __asm__(".globl\t" #name \
533 "\n\t.equ\t" #name "," #value \
534 "\n\t.type\t" #name ",@object")
535
536#elif defined(CONFIG_NIOS2) || defined(CONFIG_RISCV) || \
537 defined(CONFIG_XTENSA) || defined(CONFIG_MIPS)
538
539/* No special prefixes necessary for constants in this arch AFAICT */
540#define GEN_ABSOLUTE_SYM(name, value) \
541 __asm__(".globl\t" #name "\n\t.equ\t" #name \
542 ",%0" \
543 "\n\t.type\t" #name ",%%object" : : "n"(value))
544
545#define GEN_ABSOLUTE_SYM_KCONFIG(name, value) \
546 __asm__(".globl\t" #name \
547 "\n\t.equ\t" #name "," #value \
548 "\n\t.type\t" #name ",%object")
549
550#elif defined(CONFIG_ARCH_POSIX)
551#define GEN_ABSOLUTE_SYM(name, value) \
552 __asm__(".globl\t" #name "\n\t.equ\t" #name \
553 ",%c0" \
554 "\n\t.type\t" #name ",@object" : : "n"(value))
555
556#define GEN_ABSOLUTE_SYM_KCONFIG(name, value) \
557 __asm__(".globl\t" #name \
558 "\n\t.equ\t" #name "," #value \
559 "\n\t.type\t" #name ",@object")
560
561#elif defined(CONFIG_SPARC)
562#define GEN_ABSOLUTE_SYM(name, value) \
563 __asm__(".global\t" #name "\n\t.equ\t" #name \
564 ",%0" \
565 "\n\t.type\t" #name ",#object" : : "n"(value))
566
567#define GEN_ABSOLUTE_SYM_KCONFIG(name, value) \
568 __asm__(".globl\t" #name \
569 "\n\t.equ\t" #name "," #value \
570 "\n\t.type\t" #name ",#object")
571
572#else
573#error processor architecture not supported
574#endif
575
576#define compiler_barrier() do { \
577 __asm__ __volatile__ ("" ::: "memory"); \
578} while (false)
579
589#define Z_MAX(a, b) ({ \
590 /* random suffix to avoid naming conflict */ \
591 __typeof__(a) _value_a_ = (a); \
592 __typeof__(b) _value_b_ = (b); \
593 (_value_a_ > _value_b_) ? _value_a_ : _value_b_; \
594 })
595
601#define Z_MIN(a, b) ({ \
602 /* random suffix to avoid naming conflict */ \
603 __typeof__(a) _value_a_ = (a); \
604 __typeof__(b) _value_b_ = (b); \
605 (_value_a_ < _value_b_) ? _value_a_ : _value_b_; \
606 })
607
613#define Z_CLAMP(val, low, high) ({ \
614 /* random suffix to avoid naming conflict */ \
615 __typeof__(val) _value_val_ = (val); \
616 __typeof__(low) _value_low_ = (low); \
617 __typeof__(high) _value_high_ = (high); \
618 (_value_val_ < _value_low_) ? _value_low_ : \
619 (_value_val_ > _value_high_) ? _value_high_ : \
620 _value_val_; \
621 })
622
629#define Z_POW2_CEIL(x) \
630 ((x) <= 2UL ? (x) : (1UL << (8 * sizeof(long) - __builtin_clzl((x) - 1))))
631
638#define Z_IS_POW2(x) (((x) != 0) && (((x) & ((x)-1)) == 0))
639
640#if defined(CONFIG_ASAN) && defined(__clang__)
641#define __noasan __attribute__((no_sanitize("address")))
642#else
643#define __noasan
644#endif
645
646#if defined(CONFIG_UBSAN)
647#define __noubsan __attribute__((no_sanitize("undefined")))
648#else
649#define __noubsan
650#endif
651
657#if (TOOLCHAIN_GCC_VERSION >= 110000) || \
658 (defined(TOOLCHAIN_CLANG_VERSION) && (TOOLCHAIN_CLANG_VERSION >= 70000))
659#define FUNC_NO_STACK_PROTECTOR __attribute__((no_stack_protector))
660#else
661#define FUNC_NO_STACK_PROTECTOR
662#endif
663
664#define TOOLCHAIN_IGNORE_WSHADOW_BEGIN \
665 _Pragma("GCC diagnostic push") \
666 _Pragma("GCC diagnostic ignored \"-Wshadow\"")
667
668#define TOOLCHAIN_IGNORE_WSHADOW_END \
669 _Pragma("GCC diagnostic pop")
670
671#endif /* !_LINKER */
672#endif /* ZEPHYR_INCLUDE_TOOLCHAIN_GCC_H_ */
Common toolchain abstraction.