xref: /freebsd/lib/libc/csu/powerpc64/reloc.c (revision 5036d9652a5701d00e9e40ea942c278e9f77d33d)
1 /*-
2  * Copyright (c) 2019 Leandro Lupori
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  *
10  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
11  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
12  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
13  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
14  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
15  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
16  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
18  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
19  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
20  * SUCH DAMAGE.
21  */
22 
23 static uint32_t cpu_features;
24 static uint32_t cpu_features2;
25 
26 static void
27 ifunc_init(const Elf_Auxinfo *aux)
28 {
29 	/* Digest the auxiliary vector. */
30 	for (;  aux->a_type != AT_NULL; aux++) {
31 		switch (aux->a_type) {
32 		case AT_HWCAP:
33 			cpu_features = (uint32_t)aux->a_un.a_val;
34 			break;
35 		case AT_HWCAP2:
36 			cpu_features2 = (uint32_t)aux->a_un.a_val;
37 			break;
38 		}
39 	}
40 }
41 
42 static void
43 crt1_handle_rela(const Elf_Rela *r)
44 {
45 	typedef Elf_Addr (*ifunc_resolver_t)(
46 	    uint32_t, uint32_t, uint64_t, uint64_t,
47 	    uint64_t, uint64_t, uint64_t, uint64_t);
48 	Elf_Addr *ptr, *where, target;
49 
50 	switch (ELF_R_TYPE(r->r_info)) {
51 	case R_PPC_IRELATIVE:
52 		ptr = (Elf_Addr *)r->r_addend;
53 		where = (Elf_Addr *)r->r_offset;
54 		target = ((ifunc_resolver_t)ptr)(cpu_features, cpu_features2,
55 		    0, 0, 0, 0, 0, 0);
56 		*where = target;
57 		break;
58 	}
59 }
60