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