newlib/libc/machine/aarch64/asmdefs.h

   1 /*
   2  * Macros for asm code.  AArch64 version.
   3  *
   4  * Copyright (c) 2019-2023, Arm Limited.
   5  * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
   6  */
   7
   8 #ifndef _ASMDEFS_H
   9 #define _ASMDEFS_H
  10
  11 /* Branch Target Identitication support.  */
  12 #define BTI_C           hint    34
  13 #define BTI_J           hint    36
  14 /* Return address signing support (pac-ret).  */
  15 #define PACIASP         hint    25; .cfi_window_save
  16 #define AUTIASP         hint    29; .cfi_window_save
  17
  18 /* GNU_PROPERTY_AARCH64_* macros from elf.h.  */
  19 #define FEATURE_1_AND 0xc0000000
  20 #define FEATURE_1_BTI 1
  21 #define FEATURE_1_PAC 2
  22
  23 /* Add a NT_GNU_PROPERTY_TYPE_0 note.  */
  24 #ifdef __ILP32__
  25 #define GNU_PROPERTY(type, value)       \
  26   .section .note.gnu.property, "a";     \
  27   .p2align 2;                           \
  28   .word 4;                              \
  29   .word 12;                             \
  30   .word 5;                              \
  31   .asciz "GNU";                         \
  32   .word type;                           \
  33   .word 4;                              \
  34   .word value;                          \
  35   .text
  36 #else
  37 #define GNU_PROPERTY(type, value)       \
  38   .section .note.gnu.property, "a";     \
  39   .p2align 3;                           \
  40   .word 4;                              \
  41   .word 16;                             \
  42   .word 5;                              \
  43   .asciz "GNU";                         \
  44   .word type;                           \
  45   .word 4;                              \
  46   .word value;                          \
  47   .word 0;                              \
  48   .text
  49 #endif
  50
  51 /* If set then the GNU Property Note section will be added to
  52    mark objects to support BTI and PAC-RET.  */
  53 #ifndef WANT_GNU_PROPERTY
  54 #define WANT_GNU_PROPERTY 1
  55 #endif
  56
  57 #if WANT_GNU_PROPERTY
  58 /* Add property note with supported features to all asm files.  */
  59 GNU_PROPERTY (FEATURE_1_AND, FEATURE_1_BTI|FEATURE_1_PAC)
  60 #endif
  61
  62 #define ENTRY_ALIGN(name, alignment)    \
  63   .global name;         \
  64   .type name,%function; \
  65   .align alignment;             \
  66   name:                 \
  67   .cfi_startproc;       \
  68   BTI_C;
  69
  70 #define ENTRY(name)     ENTRY_ALIGN(name, 6)
  71
  72 #define ENTRY_ALIAS(name)       \
  73   .global name;         \
  74   .type name,%function; \
  75   name:
  76
  77 #define END(name)       \
  78   .cfi_endproc;         \
  79   .size name, .-name;
  80
  81 #define L(l) .L ## l
  82
  83 #ifdef __ILP32__
  84   /* Sanitize padding bits of pointer arguments as per aapcs64 */
  85 #define PTR_ARG(n)  mov w##n, w##n
  86 #else
  87 #define PTR_ARG(n)
  88 #endif
  89
  90 #ifdef __ILP32__
  91   /* Sanitize padding bits of size arguments as per aapcs64 */
  92 #define SIZE_ARG(n)  mov w##n, w##n
  93 #else
  94 #define SIZE_ARG(n)
  95 #endif
  96
  97 /* Compiler supports SVE instructions  */
  98 #ifndef HAVE_SVE
  99 # if __aarch64__ && (__GNUC__ >= 8 || __clang_major__ >= 5)
 100 #   define HAVE_SVE 1
 101 # else
 102 #   define HAVE_SVE 0
 103 # endif
 104 #endif
 105
 106 #endif