volatile_utils.h File Reference

Utility functions for non-atomic but volatile access. More...

Detailed Description

Utility functions for non-atomic but volatile access.

Author

Marian Buschsieweke maria.nosp@m.n.bu.nosp@m.schsi.nosp@m.ewek.nosp@m.e@ovg.nosp@m.u.de

This functions intentionally have the same signature as the Utility functions for atomic access but don't guarantee atomic access and sequential consistency (or any other consistency). They basically only guarantee that no compiler optimization is applied to that operation and that the compiler will not reorder these operations in regard to each other or other volatile accesses.

Warning

In most cases using this over Utility functions for atomic access is a bug!

Definition in file volatile_utils.h.

#include <stdint.h>

Include dependency graph for volatile_utils.h:

Go to the source code of this file.

Functions
static uint8_t	volatile_load_u8 (const volatile uint8_t *var)
	Load an 8 bit value completely unoptimized.
static uint16_t	volatile_load_u16 (const volatile uint16_t *var)
	Load an 16 bit value completely unoptimized.
static uint32_t	volatile_load_u32 (const volatile uint32_t *var)
	Load an 32 bit value completely unoptimized.
static uint64_t	volatile_load_u64 (const volatile uint64_t *var)
	Load an 64 bit value completely unoptimized.
static void	volatile_store_u8 (volatile uint8_t *dest, uint8_t val)
	Store an 8 bit value completely unoptimized.
static void	volatile_store_u16 (volatile uint16_t *dest, uint16_t val)
	Store a 16 bit value completely unoptimized.
static void	volatile_store_u32 (volatile uint32_t *dest, uint32_t val)
	Store a 32 bit value completely unoptimized.
static void	volatile_store_u64 (volatile uint64_t *dest, uint64_t val)
	Store a 64 bit value completely unoptimized.
static uint8_t	volatile_fetch_add_u8 (volatile uint8_t *dest, uint8_t val)
	Unoptimized version of *dest += val
static uint8_t	volatile_fetch_sub_u8 (volatile uint8_t *dest, uint8_t val)
	Unoptimized version of *dest -= val
static uint8_t	volatile_fetch_or_u8 (volatile uint8_t *dest, uint8_t val)
	Unoptimized version of *dest |= val
static uint8_t	volatile_fetch_xor_u8 (volatile uint8_t *dest, uint8_t val)
	Unoptimized version of *dest ^= val
static uint8_t	volatile_fetch_and_u8 (volatile uint8_t *dest, uint8_t val)
	Unoptimized version of *dest &= val
static uint16_t	volatile_fetch_add_u16 (volatile uint16_t *dest, uint16_t val)
	Unoptimized version of *dest += val
static uint16_t	volatile_fetch_sub_u16 (volatile uint16_t *dest, uint16_t val)
	Unoptimized version of *dest -= val
static uint16_t	volatile_fetch_or_u16 (volatile uint16_t *dest, uint16_t val)
	Unoptimized version of *dest |= val
static uint16_t	volatile_fetch_xor_u16 (volatile uint16_t *dest, uint16_t val)
	Unoptimized version of *dest ^= val
static uint16_t	volatile_fetch_and_u16 (volatile uint16_t *dest, uint16_t val)
	Unoptimized version of *dest &= val
static uint32_t	volatile_fetch_add_u32 (volatile uint32_t *dest, uint32_t val)
	Unoptimized version of *dest += val
static uint32_t	volatile_fetch_sub_u32 (volatile uint32_t *dest, uint32_t val)
	Unoptimized version of *dest -= val
static uint32_t	volatile_fetch_or_u32 (volatile uint32_t *dest, uint32_t val)
	Unoptimized version of *dest |= val
static uint32_t	volatile_fetch_xor_u32 (volatile uint32_t *dest, uint32_t val)
	Unoptimized version of *dest ^= val
static uint32_t	volatile_fetch_and_u32 (volatile uint32_t *dest, uint32_t val)
	Unoptimized version of *dest &= val
static uint64_t	volatile_fetch_add_u64 (volatile uint64_t *dest, uint64_t val)
	Unoptimized version of *dest += val
static uint64_t	volatile_fetch_sub_u64 (volatile uint64_t *dest, uint64_t val)
	Unoptimized version of *dest -= val
static uint64_t	volatile_fetch_or_u64 (volatile uint64_t *dest, uint64_t val)
	Unoptimized version of *dest |= val
static uint64_t	volatile_fetch_xor_u64 (volatile uint64_t *dest, uint64_t val)
	Unoptimized version of *dest ^= val
static uint64_t	volatile_fetch_and_u64 (volatile uint64_t *dest, uint64_t val)
	Unoptimized version of *dest &= val