1//===-- hwasan_setjmp_riscv64.S -------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file is a part of HWAddressSanitizer.
10// setjmp interceptor for risc-v.
11// HWAddressSanitizer runtime.
12//===----------------------------------------------------------------------===//
13
14#include "sanitizer_common/sanitizer_asm.h"
15#include "builtins/assembly.h"
16
17#if HWASAN_WITH_INTERCEPTORS && defined(__riscv) && (__riscv_xlen == 64)
18#include "sanitizer_common/sanitizer_platform.h"
19
20// We want to save the context of the calling function.
21// That requires
22// 1) No modification of the link register by this function.
23// 2) No modification of the stack pointer by this function.
24// 3) (no modification of any other saved register, but that's not really going
25// to occur, and hence isn't as much of a worry).
26//
27// There's essentially no way to ensure that the compiler will not modify the
28// stack pointer when compiling a C function.
29// Hence we have to write this function in assembly.
30
31.section .text
32.file "hwasan_setjmp_riscv64.S"
33
34.global __interceptor_setjmp
35ASM_TYPE_FUNCTION(__interceptor_setjmp)
36__interceptor_setjmp:
37  CFI_STARTPROC
38  addi x11, x0, 0
39  tail __interceptor_sigsetjmp
40  CFI_ENDPROC
41ASM_SIZE(__interceptor_setjmp)
42
43.global __interceptor_sigsetjmp
44ASM_TYPE_FUNCTION(__interceptor_sigsetjmp)
45__interceptor_sigsetjmp:
46  CFI_STARTPROC
47  sd    ra,   0<<3(x10)
48  sd    s0,   1<<3(x10)
49  sd    s1,   2<<3(x10)
50  sd    s2,   3<<3(x10)
51  sd    s3,   4<<3(x10)
52  sd    s4,   5<<3(x10)
53  sd    s5,   6<<3(x10)
54  sd    s6,   7<<3(x10)
55  sd    s7,   8<<3(x10)
56  sd    s8,   9<<3(x10)
57  sd    s9,   10<<3(x10)
58  sd    s10,  11<<3(x10)
59  sd    s11,  12<<3(x10)
60  sd    sp,   13<<3(x10)
61#if __riscv_float_abi_double
62  fsd   fs0,  14<<3(x10)
63  fsd   fs1,  15<<3(x10)
64  fsd   fs2,  16<<3(x10)
65  fsd   fs3,  17<<3(x10)
66  fsd   fs4,  18<<3(x10)
67  fsd   fs5,  19<<3(x10)
68  fsd   fs6,  20<<3(x10)
69  fsd   fs7,  21<<3(x10)
70  fsd   fs8,  22<<3(x10)
71  fsd   fs9,  23<<3(x10)
72  fsd   fs10, 24<<3(x10)
73  fsd   fs11, 25<<3(x10)
74#elif __riscv_float_abi_soft
75#else
76# error "Unsupported case"
77#endif
78  // We always have the second argument to __sigjmp_save (savemask) set, since
79  // the _setjmp function above has set it for us as `false`.
80  // This function is defined in hwasan_interceptors.cc
81  tail __sigjmp_save
82  CFI_ENDPROC
83ASM_SIZE(__interceptor_sigsetjmp)
84
85
86.macro WEAK_ALIAS first second
87  .weak \second
88  .equ \second\(), \first
89.endm
90
91WEAK_ALIAS __interceptor_sigsetjmp, __sigsetjmp
92
93WEAK_ALIAS __interceptor_setjmp, _setjmp
94#endif
95
96// We do not need executable stack.
97NO_EXEC_STACK_DIRECTIVE
98