cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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compiler-gcc.h (4669B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef __LINUX_COMPILER_TYPES_H
      3#error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead."
      4#endif
      5
      6/*
      7 * Common definitions for all gcc versions go here.
      8 */
      9#define GCC_VERSION (__GNUC__ * 10000		\
     10		     + __GNUC_MINOR__ * 100	\
     11		     + __GNUC_PATCHLEVEL__)
     12
     13/*
     14 * This macro obfuscates arithmetic on a variable address so that gcc
     15 * shouldn't recognize the original var, and make assumptions about it.
     16 *
     17 * This is needed because the C standard makes it undefined to do
     18 * pointer arithmetic on "objects" outside their boundaries and the
     19 * gcc optimizers assume this is the case. In particular they
     20 * assume such arithmetic does not wrap.
     21 *
     22 * A miscompilation has been observed because of this on PPC.
     23 * To work around it we hide the relationship of the pointer and the object
     24 * using this macro.
     25 *
     26 * Versions of the ppc64 compiler before 4.1 had a bug where use of
     27 * RELOC_HIDE could trash r30. The bug can be worked around by changing
     28 * the inline assembly constraint from =g to =r, in this particular
     29 * case either is valid.
     30 */
     31#define RELOC_HIDE(ptr, off)						\
     32({									\
     33	unsigned long __ptr;						\
     34	__asm__ ("" : "=r"(__ptr) : "0"(ptr));				\
     35	(typeof(ptr)) (__ptr + (off));					\
     36})
     37
     38#ifdef CONFIG_RETPOLINE
     39#define __noretpoline __attribute__((__indirect_branch__("keep")))
     40#endif
     41
     42#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
     43
     44#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)
     45#define __latent_entropy __attribute__((latent_entropy))
     46#endif
     47
     48/*
     49 * calling noreturn functions, __builtin_unreachable() and __builtin_trap()
     50 * confuse the stack allocation in gcc, leading to overly large stack
     51 * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
     52 *
     53 * Adding an empty inline assembly before it works around the problem
     54 */
     55#define barrier_before_unreachable() asm volatile("")
     56
     57/*
     58 * Mark a position in code as unreachable.  This can be used to
     59 * suppress control flow warnings after asm blocks that transfer
     60 * control elsewhere.
     61 */
     62#define unreachable() \
     63	do {					\
     64		annotate_unreachable();		\
     65		barrier_before_unreachable();	\
     66		__builtin_unreachable();	\
     67	} while (0)
     68
     69/*
     70 * GCC 'asm goto' miscompiles certain code sequences:
     71 *
     72 *   http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
     73 *
     74 * Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
     75 *
     76 * (asm goto is automatically volatile - the naming reflects this.)
     77 */
     78#define asm_volatile_goto(x...)	do { asm goto(x); asm (""); } while (0)
     79
     80#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP)
     81#define __HAVE_BUILTIN_BSWAP32__
     82#define __HAVE_BUILTIN_BSWAP64__
     83#define __HAVE_BUILTIN_BSWAP16__
     84#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
     85
     86#if GCC_VERSION >= 70000
     87#define KASAN_ABI_VERSION 5
     88#else
     89#define KASAN_ABI_VERSION 4
     90#endif
     91
     92#ifdef CONFIG_SHADOW_CALL_STACK
     93#define __noscs __attribute__((__no_sanitize__("shadow-call-stack")))
     94#endif
     95
     96#if __has_attribute(__no_sanitize_address__)
     97#define __no_sanitize_address __attribute__((no_sanitize_address))
     98#else
     99#define __no_sanitize_address
    100#endif
    101
    102#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)
    103#define __no_sanitize_thread __attribute__((no_sanitize_thread))
    104#else
    105#define __no_sanitize_thread
    106#endif
    107
    108#if __has_attribute(__no_sanitize_undefined__)
    109#define __no_sanitize_undefined __attribute__((no_sanitize_undefined))
    110#else
    111#define __no_sanitize_undefined
    112#endif
    113
    114#if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__)
    115#define __no_sanitize_coverage __attribute__((no_sanitize_coverage))
    116#else
    117#define __no_sanitize_coverage
    118#endif
    119
    120/*
    121 * Treat __SANITIZE_HWADDRESS__ the same as __SANITIZE_ADDRESS__ in the kernel,
    122 * matching the defines used by Clang.
    123 */
    124#ifdef __SANITIZE_HWADDRESS__
    125#define __SANITIZE_ADDRESS__
    126#endif
    127
    128/*
    129 * Turn individual warnings and errors on and off locally, depending
    130 * on version.
    131 */
    132#define __diag_GCC(version, severity, s) \
    133	__diag_GCC_ ## version(__diag_GCC_ ## severity s)
    134
    135/* Severity used in pragma directives */
    136#define __diag_GCC_ignore	ignored
    137#define __diag_GCC_warn		warning
    138#define __diag_GCC_error	error
    139
    140#define __diag_str1(s)		#s
    141#define __diag_str(s)		__diag_str1(s)
    142#define __diag(s)		_Pragma(__diag_str(GCC diagnostic s))
    143
    144#if GCC_VERSION >= 80000
    145#define __diag_GCC_8(s)		__diag(s)
    146#else
    147#define __diag_GCC_8(s)
    148#endif
    149
    150#define __diag_ignore_all(option, comment) \
    151	__diag_GCC(8, ignore, option)
    152
    153/*
    154 * Prior to 9.1, -Wno-alloc-size-larger-than (and therefore the "alloc_size"
    155 * attribute) do not work, and must be disabled.
    156 */
    157#if GCC_VERSION < 90100
    158#undef __alloc_size__
    159#endif