1 /*
2  * host-signal.h: signal info dependent on the host architecture
3  *
4  * Copyright (c) 2003-2005 Fabrice Bellard
5  * Copyright (c) 2021 WANG Xuerui <git@xen0n.name>
6  *
7  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
8  * See the COPYING file in the top-level directory.
9  */
10 
11 #ifndef LOONGARCH64_HOST_SIGNAL_H
12 #define LOONGARCH64_HOST_SIGNAL_H
13 
14 static inline uintptr_t host_signal_pc(ucontext_t *uc)
15 {
16     return uc->uc_mcontext.__pc;
17 }
18 
19 static inline void host_signal_set_pc(ucontext_t *uc, uintptr_t pc)
20 {
21     uc->uc_mcontext.__pc = pc;
22 }
23 
24 static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
25 {
26     const uint32_t *pinsn = (const uint32_t *)host_signal_pc(uc);
27     uint32_t insn = pinsn[0];
28 
29     /* Detect store by reading the instruction at the program counter.  */
30     switch ((insn >> 26) & 0b111111) {
31     case 0b001000: /* {ll,sc}.[wd] */
32         switch ((insn >> 24) & 0b11) {
33         case 0b01: /* sc.w */
34         case 0b11: /* sc.d */
35             return true;
36         }
37         break;
38     case 0b001001: /* {ld,st}ox4.[wd] ({ld,st}ptr.[wd]) */
39         switch ((insn >> 24) & 0b11) {
40         case 0b01: /* stox4.w (stptr.w) */
41         case 0b11: /* stox4.d (stptr.d) */
42             return true;
43         }
44         break;
45     case 0b001010: /* {ld,st}.* family */
46         switch ((insn >> 22) & 0b1111) {
47         case 0b0100: /* st.b */
48         case 0b0101: /* st.h */
49         case 0b0110: /* st.w */
50         case 0b0111: /* st.d */
51         case 0b1101: /* fst.s */
52         case 0b1111: /* fst.d */
53             return true;
54         }
55         break;
56     case 0b001110: /* indexed, atomic, bounds-checking memory operations */
57         switch ((insn >> 15) & 0b11111111111) {
58         case 0b00000100000: /* stx.b */
59         case 0b00000101000: /* stx.h */
60         case 0b00000110000: /* stx.w */
61         case 0b00000111000: /* stx.d */
62         case 0b00001110000: /* fstx.s */
63         case 0b00001111000: /* fstx.d */
64         case 0b00011101100: /* fstgt.s */
65         case 0b00011101101: /* fstgt.d */
66         case 0b00011101110: /* fstle.s */
67         case 0b00011101111: /* fstle.d */
68         case 0b00011111000: /* stgt.b */
69         case 0b00011111001: /* stgt.h */
70         case 0b00011111010: /* stgt.w */
71         case 0b00011111011: /* stgt.d */
72         case 0b00011111100: /* stle.b */
73         case 0b00011111101: /* stle.h */
74         case 0b00011111110: /* stle.w */
75         case 0b00011111111: /* stle.d */
76         case 0b00011000000 ... 0b00011100011: /* am* insns */
77             return true;
78         }
79         break;
80     }
81 
82     return false;
83 }
84 
85 #endif
86