diff options
Diffstat (limited to 'libexec/rtld-elf/sparc64/rtld_start.S')
| -rw-r--r-- | libexec/rtld-elf/sparc64/rtld_start.S | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/libexec/rtld-elf/sparc64/rtld_start.S b/libexec/rtld-elf/sparc64/rtld_start.S new file mode 100644 index 0000000..7443ed6 --- /dev/null +++ b/libexec/rtld-elf/sparc64/rtld_start.S @@ -0,0 +1,143 @@ +/* $NetBSD: rtld_start.S,v 1.5 2001/08/14 22:17:48 eeh Exp $ */ + +/*- + * Copyright (c) 2001 Jake Burkholder. + * Copyright (c) 2000 Eduardo Horvath. + * Copyright (c) 1999 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Christos Zoulas and Paul Kranenburg. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the NetBSD + * Foundation, Inc. and its contributors. + * 4. Neither the name of The NetBSD Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include <machine/asm.h> + +/* + * ELF: + * On startup the stack should contain 16 extended word register save + * area, followed by the arg count, etc. + */ + +ENTRY(.rtld_start) + clr %fp + mov %o0, %l0 + mov %o3, %l1 + + sub %sp, 16, %sp + add %sp, SPOFF + CCFSZ + 0x0, %o1 + call _rtld + add %sp, SPOFF + CCFSZ + 0x8, %o2 + + ldx [%sp + SPOFF + CCFSZ + 0x0], %o1 + ldx [%sp + SPOFF + CCFSZ + 0x8], %o2 + add %sp, 16, %sp + + mov %l1, %o3 + jmp %o0 + mov %l0, %o0 + + /* + * We have two separate entry points to the runtime linker. + * I'm implementing this following the SPARC v9 ABI spec. + * + * _rtld_bind_start_0(x, y) is called from .PLT0, and is used for + * PLT entries above 32768. + * + * _rtld_bind_start_1(x, y) is called from .PLT1, and is used for + * PLT entries below 32768. + * + * The first two entries of PLT2 contain the xword object pointer. + * + * These routines are called with two longword arguments, + * x and y. To calculate the address of the entry, + * _rtld_bind_start_1(x, y) does: + * + * n = x >> 15; + * + * and _rtld_bind_start_0(x, y) does: + * + * i = x - y + 1048596; + * n = 32768 + (i/5120)*160 + (i%5120)/24; + * + * Neither routine needs to issue a save since it's already been + * done in the PLT entry. + */ + +ENTRY(_rtld_bind_start_0) + sethi %hi(1048596), %l1 + sub %o0, %o1, %l0 /* x - y */ + or %l1, %lo(1048596), %l1 + add %l0, %l1, %l0 /* x - y + 1048596 */ + + sdivx %l0, 5120, %l1 /* Calculate i/5120 */ + ldx [%o1 + (10*4)], %o0 /* Load object pointer from PLT2 */ + sub %l0, %l1, %l2 /* And i%5120 */ + + /* Let the division churn for a bit. */ + sdivx %l2, 14, %l4 /* (i%5120)/24 */ + + /* 160 is (32 * 5) or (32 * (4 + 1)) */ + sllx %l1, 2, %l3 /* 4 * (i/5120) */ + add %l1, %l3, %l3 /* 5 * (i/5120) */ + sllx %l3, 5, %l3 /* 32 * 5 * (i/5120) */ + + sethi %hi(32768), %l6 + add %l3, %l4, %l5 /* %l5 = (i/5120)*160 + (i%5120)/24; */ + add %l5, %l6, %l5 + + sllx %l5, 1, %l6 /* Each element is an Elf_Rela which */ + add %l6, %l5, %l5 /* is 3 longwords or 24 bytes. */ + sllx %l5, 3, %l5 /* So multiply by 24. */ + + call _rtld_bind /* Call _rtld_bind(obj, offset) */ + mov %l5, %o1 + + jmp %o0 /* return value == function address */ + restore /* Dump our stack frame */ + +ENTRY(_rtld_bind_start_1) + srax %o0, 15, %o2 /* %o0 is the index to our PLT slot */ + sub %o2, 4, %o2 /* XXX: 4 entries are reserved */ + + sllx %o2, 1, %o3 /* Each element is an Elf_Rela which */ + add %o3, %o2, %o2 /* is 3 longwords or 24 bytes. */ + sllx %o2, 3, %o2 /* So multiply by 24. */ + + ldx [%o1 + 8], %o0 /* The object pointer is at [%o1 + 8] */ + + call _rtld_bind /* Call _rtld_bind(obj, offset) */ + mov %o2, %o1 + + jmp %o0 /* return value == function address */ + restore /* Dump our stack frame */ + |
