1 //===--------- inline implementation of riscv syscalls ------------* C++ *-===//
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 #ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_RISCV_SYSCALL_H
10 #define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_RISCV_SYSCALL_H
11
12 #include "src/__support/common.h"
13 #include "src/__support/macros/config.h"
14
15 #define REGISTER_DECL_0 \
16 register long a7 __asm__("a7") = number; \
17 register long a0 __asm__("a0");
18 #define REGISTER_DECL_1 \
19 register long a7 __asm__("a7") = number; \
20 register long a0 __asm__("a0") = arg1;
21 #define REGISTER_DECL_2 REGISTER_DECL_1 register long a1 __asm__("a1") = arg2;
22 #define REGISTER_DECL_3 \
23 REGISTER_DECL_2 \
24 register long a2 __asm__("a2") = arg3;
25 #define REGISTER_DECL_4 \
26 REGISTER_DECL_3 \
27 register long a3 __asm__("a3") = arg4;
28 #define REGISTER_DECL_5 \
29 REGISTER_DECL_4 \
30 register long a4 __asm__("a4") = arg5;
31 #define REGISTER_DECL_6 \
32 REGISTER_DECL_5 \
33 register long a5 __asm__("a5") = arg6;
34
35 #define REGISTER_CONSTRAINT_0 "r"(a7)
36 #define REGISTER_CONSTRAINT_1 REGISTER_CONSTRAINT_0, "r"(a0)
37 #define REGISTER_CONSTRAINT_2 REGISTER_CONSTRAINT_1, "r"(a1)
38 #define REGISTER_CONSTRAINT_3 REGISTER_CONSTRAINT_2, "r"(a2)
39 #define REGISTER_CONSTRAINT_4 REGISTER_CONSTRAINT_3, "r"(a3)
40 #define REGISTER_CONSTRAINT_5 REGISTER_CONSTRAINT_4, "r"(a4)
41 #define REGISTER_CONSTRAINT_6 REGISTER_CONSTRAINT_5, "r"(a5)
42
43 #define SYSCALL_INSTR(input_constraint) \
44 LIBC_INLINE_ASM("ecall\n\t" : "=r"(a0) : input_constraint : "memory")
45
46 namespace LIBC_NAMESPACE_DECL {
47
syscall_impl(long number)48 LIBC_INLINE long syscall_impl(long number) {
49 REGISTER_DECL_0;
50 SYSCALL_INSTR(REGISTER_CONSTRAINT_0);
51 return a0;
52 }
53
syscall_impl(long number,long arg1)54 LIBC_INLINE long syscall_impl(long number, long arg1) {
55 REGISTER_DECL_1;
56 SYSCALL_INSTR(REGISTER_CONSTRAINT_1);
57 return a0;
58 }
59
syscall_impl(long number,long arg1,long arg2)60 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2) {
61 REGISTER_DECL_2;
62 SYSCALL_INSTR(REGISTER_CONSTRAINT_2);
63 return a0;
64 }
65
syscall_impl(long number,long arg1,long arg2,long arg3)66 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3) {
67 REGISTER_DECL_3;
68 SYSCALL_INSTR(REGISTER_CONSTRAINT_3);
69 return a0;
70 }
71
syscall_impl(long number,long arg1,long arg2,long arg3,long arg4)72 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
73 long arg4) {
74 REGISTER_DECL_4;
75 SYSCALL_INSTR(REGISTER_CONSTRAINT_4);
76 return a0;
77 }
78
syscall_impl(long number,long arg1,long arg2,long arg3,long arg4,long arg5)79 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
80 long arg4, long arg5) {
81 REGISTER_DECL_5;
82 SYSCALL_INSTR(REGISTER_CONSTRAINT_5);
83 return a0;
84 }
85
syscall_impl(long number,long arg1,long arg2,long arg3,long arg4,long arg5,long arg6)86 LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
87 long arg4, long arg5, long arg6) {
88 REGISTER_DECL_6;
89 SYSCALL_INSTR(REGISTER_CONSTRAINT_6);
90 return a0;
91 }
92
93 } // namespace LIBC_NAMESPACE_DECL
94
95 #undef REGISTER_DECL_0
96 #undef REGISTER_DECL_1
97 #undef REGISTER_DECL_2
98 #undef REGISTER_DECL_3
99 #undef REGISTER_DECL_4
100 #undef REGISTER_DECL_5
101 #undef REGISTER_DECL_6
102
103 #undef REGISTER_CONSTRAINT_0
104 #undef REGISTER_CONSTRAINT_1
105 #undef REGISTER_CONSTRAINT_2
106 #undef REGISTER_CONSTRAINT_3
107 #undef REGISTER_CONSTRAINT_4
108 #undef REGISTER_CONSTRAINT_5
109 #undef REGISTER_CONSTRAINT_6
110
111 #endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_RISCV_SYSCALL_H
112