gcc.h

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/*
 * Copyright (c) 2010-2014,2017 Wind River Systems, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef ZEPHYR_INCLUDE_TOOLCHAIN_GCC_H_
#define ZEPHYR_INCLUDE_TOOLCHAIN_GCC_H_
 
/*
 * Older versions of GCC do not define __BYTE_ORDER__, so it must be manually
 * detected and defined using arch-specific definitions.
 */
 
#ifndef _LINKER
 
#ifndef __ORDER_BIG_ENDIAN__
#define __ORDER_BIG_ENDIAN__            (1)
#endif
 
#ifndef __ORDER_LITTLE_ENDIAN__
#define __ORDER_LITTLE_ENDIAN__         (2)
#endif
 
#ifndef __BYTE_ORDER__
#if defined(__BIG_ENDIAN__) || defined(__ARMEB__) || \
    defined(__THUMBEB__) || defined(__AARCH64EB__) || \
    defined(__MIPSEB__) || defined(__TC32EB__)
 
#define __BYTE_ORDER__                  __ORDER_BIG_ENDIAN__
 
#elif defined(__LITTLE_ENDIAN__) || defined(__ARMEL__) || \
      defined(__THUMBEL__) || defined(__AARCH64EL__) || \
      defined(__MIPSEL__) || defined(__TC32EL__)
 
#define __BYTE_ORDER__                  __ORDER_LITTLE_ENDIAN__
 
#else
#error "__BYTE_ORDER__ is not defined and cannot be automatically resolved"
#endif
#endif
 
 
/* C++11 has static_assert built in */
#if defined(__cplusplus) && (__cplusplus >= 201103L)
#define BUILD_ASSERT(EXPR, MSG...) static_assert(EXPR, "" MSG)
 
/*
 * GCC 4.6 and higher have the C11 _Static_assert built in, and its
 * output is easier to understand than the common BUILD_ASSERT macros.
 */
#elif (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) || \
        (__STDC_VERSION__) >= 201100
#define BUILD_ASSERT(EXPR, MSG...) _Static_assert(EXPR, "" MSG)
#else
#define BUILD_ASSERT(EXPR, MSG...)
#endif
 
#ifdef __cplusplus
#define ZRESTRICT __restrict
#else
#define ZRESTRICT restrict
#endif
 
#include <toolchain/common.h>
#include <stdbool.h>
 
#define ALIAS_OF(of) __attribute__((alias(#of)))
 
#define FUNC_ALIAS(real_func, new_alias, return_type) \
        return_type new_alias() ALIAS_OF(real_func)
 
#if defined(CONFIG_ARCH_POSIX)
#include <arch/posix/posix_trace.h>
 
/*let's not segfault if this were to happen for some reason*/
#define CODE_UNREACHABLE \
{\
        posix_print_error_and_exit("CODE_UNREACHABLE reached from %s:%d\n",\
                __FILE__, __LINE__);\
        __builtin_unreachable(); \
}
#else
#define CODE_UNREACHABLE __builtin_unreachable()
#endif
#define FUNC_NORETURN    __attribute__((__noreturn__))
 
/* The GNU assembler for Cortex-M3 uses # for immediate values, not
 * comments, so the @nobits# trick does not work.
 */
#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
#define _NODATA_SECTION(segment)  __attribute__((section(#segment)))
#else
#define _NODATA_SECTION(segment)                                \
        __attribute__((section(#segment ",\"wa\",@nobits#")))
#endif
 
/* Unaligned access */
#define UNALIGNED_GET(p)                                                \
__extension__ ({                                                        \
        struct  __attribute__((__packed__)) {                           \
                __typeof__(*(p)) __v;                                   \
        } *__p = (__typeof__(__p)) (p);                                 \
        __p->__v;                                                       \
})
 
 
#if __GNUC__ >= 7 && (defined(CONFIG_ARM) || defined(CONFIG_ARM64))
 
/* Version of UNALIGNED_PUT() which issues a compiler_barrier() after
 * the store. It is required to workaround an apparent optimization
 * bug in GCC for ARM Cortex-M3 and higher targets, when multiple
 * byte, half-word and word stores (strb, strh, str instructions),
 * which support unaligned access, can be coalesced into store double
 * (strd) instruction, which doesn't support unaligned access (the
 * compilers in question do this optimization ignoring __packed__
 * attribute).
 */
#define UNALIGNED_PUT(v, p)                                             \
do {                                                                    \
        struct __attribute__((__packed__)) {                            \
                __typeof__(*p) __v;                                     \
        } *__p = (__typeof__(__p)) (p);                                 \
        __p->__v = (v);                                                 \
        compiler_barrier();                                             \
} while (false)
 
#else
 
#define UNALIGNED_PUT(v, p)                                             \
do {                                                                    \
        struct __attribute__((__packed__)) {                            \
                __typeof__(*p) __v;                                     \
        } *__p = (__typeof__(__p)) (p);                                 \
        __p->__v = (v);                                               \
} while (false)
 
#endif
 
/* Double indirection to ensure section names are expanded before
 * stringification
 */
#define __GENERIC_SECTION(segment) __attribute__((section(STRINGIFY(segment))))
#define Z_GENERIC_SECTION(segment) __GENERIC_SECTION(segment)
 
#define __GENERIC_DOT_SECTION(segment) \
        __attribute__((section("." STRINGIFY(segment))))
#define Z_GENERIC_DOT_SECTION(segment) __GENERIC_DOT_SECTION(segment)
 
#define ___in_section(a, b, c) \
        __attribute__((section("." Z_STRINGIFY(a)                       \
                                "." Z_STRINGIFY(b)                      \
                                "." Z_STRINGIFY(c))))
#define __in_section(a, b, c) ___in_section(a, b, c)
 
#define __in_section_unique(seg) ___in_section(seg, __FILE__, __COUNTER__)
 
#define __in_section_unique_named(seg, name) \
        ___in_section(seg, __FILE__, name)
 
/* When using XIP, using '__ramfunc' places a function into RAM instead
 * of FLASH. Make sure '__ramfunc' is defined only when
 * CONFIG_ARCH_HAS_RAMFUNC_SUPPORT is defined, so that the compiler can
 * report an error if '__ramfunc' is used but the architecture does not
 * support it.
 */
#if !defined(CONFIG_XIP)
#define __ramfunc
#elif defined(CONFIG_ARCH_HAS_RAMFUNC_SUPPORT)
#define __ramfunc       __attribute__((noinline))                       \
                        __attribute__((long_call, section(".ramfunc")))
#endif /* !CONFIG_XIP */
 
#ifndef __fallthrough
#if __GNUC__ >= 7
#define __fallthrough        __attribute__((fallthrough))
#else
#define __fallthrough
#endif  /* __GNUC__ >= 7 */
#endif
 
#ifndef __packed
#define __packed        __attribute__((__packed__))
#endif
#ifndef __aligned
#define __aligned(x)    __attribute__((__aligned__(x)))
#endif
#define __may_alias     __attribute__((__may_alias__))
#ifndef __printf_like
#define __printf_like(f, a)   __attribute__((format (printf, f, a)))
#endif
#define __used          __attribute__((__used__))
#ifndef __deprecated
#define __deprecated    __attribute__((deprecated))
#endif
#ifndef __attribute_const__
#define __attribute_const__ __attribute__((__const__))
#endif
#ifndef __must_check
#define __must_check __attribute__((warn_unused_result))
#endif
#define ARG_UNUSED(x) (void)(x)
 
#define likely(x)   __builtin_expect((bool)!!(x), true)
#define unlikely(x) __builtin_expect((bool)!!(x), false)
 
#define popcount(x) __builtin_popcount(x)
 
#ifndef __no_optimization
#define __no_optimization __attribute__((optimize("-O0")))
#endif
 
#ifndef __weak
#define __weak __attribute__((__weak__))
#endif
#define __unused __attribute__((__unused__))
 
/* Builtins with availability that depend on the compiler version. */
#if __GNUC__ >= 5
#define HAS_BUILTIN___builtin_add_overflow 1
#define HAS_BUILTIN___builtin_sub_overflow 1
#define HAS_BUILTIN___builtin_mul_overflow 1
#define HAS_BUILTIN___builtin_div_overflow 1
#endif
#if __GNUC__ >= 4
#define HAS_BUILTIN___builtin_clz 1
#define HAS_BUILTIN___builtin_clzl 1
#define HAS_BUILTIN___builtin_clzll 1
#define HAS_BUILTIN___builtin_ctz 1
#define HAS_BUILTIN___builtin_ctzl 1
#define HAS_BUILTIN___builtin_ctzll 1
#endif
 
/*
 * Be *very* careful with these. You cannot filter out __DEPRECATED_MACRO with
 * -wno-deprecated, which has implications for -Werror.
 */
 
/*
 * Expands to nothing and generates a warning. Used like
 *
 *   #define FOO __WARN("Please use BAR instead") ...
 *
 * The warning points to the location where the macro is expanded.
 */
#define __WARN(msg) __WARN1(GCC warning msg)
#define __WARN1(s) _Pragma(#s)
 
/* Generic message */
#ifndef __DEPRECATED_MACRO
#define __DEPRECATED_MACRO __WARN("Macro is deprecated")
#endif
 
/* These macros allow having ARM asm functions callable from thumb */
 
#if defined(_ASMLANGUAGE)
 
#if defined(CONFIG_ARM)
 
#if defined(CONFIG_ASSEMBLER_ISA_THUMB2)
 
#define FUNC_CODE() .thumb;
#define FUNC_INSTR(a)
 
#else
 
#define FUNC_CODE() .code 32
#define FUNC_INSTR(a)
 
#endif /* CONFIG_ASSEMBLER_ISA_THUMB2 */
 
#else
 
#define FUNC_CODE()
#define FUNC_INSTR(a)
 
#endif /* CONFIG_ARM */
 
#endif /* _ASMLANGUAGE */
 
/*
 * These macros are used to declare assembly language symbols that need
 * to be typed properly(func or data) to be visible to the OMF tool.
 * So that the build tool could mark them as an entry point to be linked
 * correctly.  This is an elfism. Use #if 0 for a.out.
 */
 
#if defined(_ASMLANGUAGE)
 
#if defined(CONFIG_ARM) || defined(CONFIG_NIOS2) || defined(CONFIG_RISCV) \
        || defined(CONFIG_XTENSA) || defined(CONFIG_ARM64) \
        || defined(CONFIG_MIPS)
#define GTEXT(sym) .global sym; .type sym, %function
#define GDATA(sym) .global sym; .type sym, %object
#define WTEXT(sym) .weak sym; .type sym, %function
#define WDATA(sym) .weak sym; .type sym, %object
#elif defined(CONFIG_ARC)
/*
 * Need to use assembly macros because ';' is interpreted as the start of
 * a single line comment in the ARC assembler.
 */
 
.macro glbl_text symbol
        .globl \symbol
        .type \symbol, %function
.endm
 
.macro glbl_data symbol
        .globl \symbol
        .type \symbol, %object
.endm
 
.macro weak_data symbol
        .weak \symbol
        .type \symbol, %object
.endm
 
#define GTEXT(sym) glbl_text sym
#define GDATA(sym) glbl_data sym
#define WDATA(sym) weak_data sym
 
#else  /* !CONFIG_ARM && !CONFIG_ARC */
#define GTEXT(sym) .globl sym; .type sym, @function
#define GDATA(sym) .globl sym; .type sym, @object
#endif
 
/*
 * These macros specify the section in which a given function or variable
 * resides.
 *
 * - SECTION_FUNC       allows only one function to reside in a sub-section
 * - SECTION_SUBSEC_FUNC allows multiple functions to reside in a sub-section
 *   This ensures that garbage collection only discards the section
 *   if all functions in the sub-section are not referenced.
 */
 
#if defined(CONFIG_ARC)
/*
 * Need to use assembly macros because ';' is interpreted as the start of
 * a single line comment in the ARC assembler.
 *
 * Also, '\‍()' is needed in the .section directive of these macros for
 * correct substitution of the 'section' variable.
 */
 
.macro section_var section, symbol
        .section .\section\‍().\symbol
        \symbol :
.endm
 
.macro section_func section, symbol
        .section .\section\().\symbol, "ax"
        FUNC_CODE()
        PERFOPT_ALIGN
        \symbol :
        FUNC_INSTR(\symbol)
.endm
 
.macro section_subsec_func section, subsection, symbol
        .section .\section\().\subsection, "ax"
        PERFOPT_ALIGN
        \symbol :
.endm
 
#define SECTION_VAR(sect, sym) section_var sect, sym
#define SECTION_FUNC(sect, sym) section_func sect, sym
#define SECTION_SUBSEC_FUNC(sect, subsec, sym) \
        section_subsec_func sect, subsec, sym
#else /* !CONFIG_ARC */
 
#define SECTION_VAR(sect, sym)  .section .sect.sym; sym:
#define SECTION_FUNC(sect, sym)                                         \
        .section .sect.sym, "ax";                                       \
                                FUNC_CODE()                             \
                                PERFOPT_ALIGN; sym :            \
                                                        FUNC_INSTR(sym)
#define SECTION_SUBSEC_FUNC(sect, subsec, sym)                          \
                .section .sect.subsec, "ax"; PERFOPT_ALIGN; sym :
 
#endif /* CONFIG_ARC */
 
#endif /* _ASMLANGUAGE */
 
#if defined(_ASMLANGUAGE)
#if defined(CONFIG_ARM)
#if defined(CONFIG_ASSEMBLER_ISA_THUMB2)
/* '.syntax unified' is a gcc-ism used in thumb-2 asm files */
#define _ASM_FILE_PROLOGUE .text; .syntax unified; .thumb
#else
#define _ASM_FILE_PROLOGUE .text; .code 32
#endif /* CONFIG_ASSEMBLER_ISA_THUMB2 */
#elif defined(CONFIG_ARM64)
#define _ASM_FILE_PROLOGUE .text
#endif /* CONFIG_ARM64 || CONFIG_ARM */
#endif /* _ASMLANGUAGE */
 
/*
 * These macros generate absolute symbols for GCC
 */
 
/* create an extern reference to the absolute symbol */
 
#define GEN_OFFSET_EXTERN(name) extern const char name[]
 
#define GEN_ABS_SYM_BEGIN(name) \
        EXTERN_C void name(void); \
        void name(void)         \
        {
 
#define GEN_ABS_SYM_END }
 
/*
 * Note that GEN_ABSOLUTE_SYM(), depending on the architecture
 * and toolchain, may restrict the range of values permitted
 * for assignment to the named symbol.
 *
 * For example, on x86, "value" is interpreated as signed
 * 32-bit integer. Passing in an unsigned 32-bit integer
 * with MSB set would result in a negative integer.
 * Moreover, GCC would error out if an integer larger
 * than 2^32-1 is passed as "value".
 */
 
/*
 * GEN_ABSOLUTE_SYM_KCONFIG() is outputted by the build system
 * to generate named symbol/value pairs for kconfigs.
 */
 
#if defined(CONFIG_ARM)
 
/*
 * GNU/ARM backend does not have a proper operand modifier which does not
 * produces prefix # followed by value, such as %0 for PowerPC, Intel, and
 * MIPS. The workaround performed here is using %B0 which converts
 * the value to ~(value). Thus "n"(~(value)) is set in operand constraint
 * to output (value) in the ARM specific GEN_OFFSET macro.
 */
 
#define GEN_ABSOLUTE_SYM(name, value)               \
        __asm__(".globl\t" #name "\n\t.equ\t" #name \
                ",%B0"                              \
                "\n\t.type\t" #name ",%%object" :  : "n"(~(value)))
 
#define GEN_ABSOLUTE_SYM_KCONFIG(name, value)       \
        __asm__(".globl\t" #name                    \
                "\n\t.equ\t" #name "," #value       \
                "\n\t.type\t" #name ",%object")
 
#elif defined(CONFIG_X86)
 
#define GEN_ABSOLUTE_SYM(name, value)               \
        __asm__(".globl\t" #name "\n\t.equ\t" #name \
                ",%c0"                              \
                "\n\t.type\t" #name ",@object" :  : "n"(value))
 
#define GEN_ABSOLUTE_SYM_KCONFIG(name, value)       \
        __asm__(".globl\t" #name                    \
                "\n\t.equ\t" #name "," #value       \
                "\n\t.type\t" #name ",@object")
 
#elif defined(CONFIG_ARC) || defined(CONFIG_ARM64)
 
#define GEN_ABSOLUTE_SYM(name, value)               \
        __asm__(".globl\t" #name "\n\t.equ\t" #name \
                ",%c0"                              \
                "\n\t.type\t" #name ",@object" :  : "n"(value))
 
#define GEN_ABSOLUTE_SYM_KCONFIG(name, value)       \
        __asm__(".globl\t" #name                    \
                "\n\t.equ\t" #name "," #value       \
                "\n\t.type\t" #name ",@object")
 
#elif defined(CONFIG_NIOS2) || defined(CONFIG_RISCV) || \
        defined(CONFIG_XTENSA) || defined(CONFIG_MIPS)
 
/* No special prefixes necessary for constants in this arch AFAICT */
#define GEN_ABSOLUTE_SYM(name, value)           \
        __asm__(".globl\t" #name "\n\t.equ\t" #name \
                ",%0"                              \
                "\n\t.type\t" #name ",%%object" :  : "n"(value))
 
#define GEN_ABSOLUTE_SYM_KCONFIG(name, value)       \
        __asm__(".globl\t" #name                    \
                "\n\t.equ\t" #name "," #value       \
                "\n\t.type\t" #name ",%object")
 
#elif defined(CONFIG_ARCH_POSIX)
#define GEN_ABSOLUTE_SYM(name, value)               \
        __asm__(".globl\t" #name "\n\t.equ\t" #name \
                ",%c0"                              \
                "\n\t.type\t" #name ",@object" :  : "n"(value))
 
#define GEN_ABSOLUTE_SYM_KCONFIG(name, value)       \
        __asm__(".globl\t" #name                    \
                "\n\t.equ\t" #name "," #value       \
                "\n\t.type\t" #name ",@object")
 
#elif defined(CONFIG_SPARC)
#define GEN_ABSOLUTE_SYM(name, value)                   \
        __asm__(".global\t" #name "\n\t.equ\t" #name    \
                ",%0"                                   \
                "\n\t.type\t" #name ",#object" : : "n"(value))
 
#define GEN_ABSOLUTE_SYM_KCONFIG(name, value)       \
        __asm__(".globl\t" #name                    \
                "\n\t.equ\t" #name "," #value       \
                "\n\t.type\t" #name ",#object")
 
#else
#error processor architecture not supported
#endif
 
#define compiler_barrier() do { \
        __asm__ __volatile__ ("" ::: "memory"); \
} while (false)
 
#define Z_MAX(a, b) ({ \
                /* random suffix to avoid naming conflict */ \
                __typeof__(a) _value_a_ = (a); \
                __typeof__(b) _value_b_ = (b); \
                _value_a_ > _value_b_ ? _value_a_ : _value_b_; \
        })
 
#define Z_MIN(a, b) ({ \
                /* random suffix to avoid naming conflict */ \
                __typeof__(a) _value_a_ = (a); \
                __typeof__(b) _value_b_ = (b); \
                _value_a_ < _value_b_ ? _value_a_ : _value_b_; \
        })
 
#define Z_CLAMP(val, low, high) ({                                             \
                /* random suffix to avoid naming conflict */                   \
                __typeof__(val) _value_val_ = (val);                           \
                __typeof__(low) _value_low_ = (low);                           \
                __typeof__(high) _value_high_ = (high);                        \
                (_value_val_ < _value_low_)  ? _value_low_ :                   \
                (_value_val_ > _value_high_) ? _value_high_ :                  \
                                               _value_val_;                    \
        })
 
#ifdef CONFIG_64BIT
#define Z_POW2_CEIL(x) ((1UL << (63U - __builtin_clzl(x))) < x ?  \
                1UL << (63U - __builtin_clzl(x) + 1U) : \
                1UL << (63U - __builtin_clzl(x)))
#else
#define Z_POW2_CEIL(x) ((1UL << (31U - __builtin_clzl(x))) < x ?  \
                1UL << (31U - __builtin_clzl(x) + 1U) : \
                1UL << (31U - __builtin_clzl(x)))
#endif
 
#endif /* !_LINKER */
#endif /* ZEPHYR_INCLUDE_TOOLCHAIN_GCC_H_ */