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authorWaldemar Brodkorb <wbx@openadk.org>2024-03-02 18:10:21 +0100
committerWaldemar Brodkorb <wbx@openadk.org>2024-03-03 05:17:16 +0100
commitc07daae85e85e6e5db12d671ae85e08e182bc94f (patch)
treefd872ec9ff558cc5164a582cd330d31b694c3eea
parent1be78c337c45d8a090ae9c658a9146b5ada620b1 (diff)
riscv32: add ldso support, enable time64.
-rw-r--r--extra/Configs/Config.in1
-rw-r--r--ldso/ldso/riscv32/dl-startup.h92
-rw-r--r--ldso/ldso/riscv32/dl-syscalls.h1
-rw-r--r--ldso/ldso/riscv32/dl-sysdep.h91
-rw-r--r--ldso/ldso/riscv32/elfinterp.c295
-rw-r--r--ldso/ldso/riscv32/resolve.S96
6 files changed, 576 insertions, 0 deletions
diff --git a/extra/Configs/Config.in b/extra/Configs/Config.in
index 5f297b492..33fa11a95 100644
--- a/extra/Configs/Config.in
+++ b/extra/Configs/Config.in
@@ -1031,6 +1031,7 @@ config UCLIBC_USE_TIME64
(TARGET_mips && !CONFIG_MIPS_N64_ABI) || \
TARGET_or1k || \
TARGET_powerpc || \
+ TARGET_riscv32 || \
TARGET_sparc || \
TARGET_xtensa
# TODO: add support for other architectures
diff --git a/ldso/ldso/riscv32/dl-startup.h b/ldso/ldso/riscv32/dl-startup.h
new file mode 100644
index 000000000..6f16918d6
--- /dev/null
+++ b/ldso/ldso/riscv32/dl-startup.h
@@ -0,0 +1,92 @@
+/*
+ * Architecture specific code used by dl-startup.c
+ * Copyright (C) 2024 Waldemar Brodkorb <wbx@uclibc-ng.org>
+ * Ported from GNU libc
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/* Copyright (C) 2011-2019 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <features.h>
+#include <sys/asm.h>
+
+#ifndef _RTLD_PROLOGUE
+# define _RTLD_PROLOGUE(entry) \
+ ".globl\t" __STRING (entry) "\n\t" \
+ ".type\t" __STRING (entry) ", @function\n" \
+ __STRING (entry) ":\n\t"
+#endif
+
+#ifndef _RTLD_EPILOGUE
+# define _RTLD_EPILOGUE(entry) \
+ ".size\t" __STRING (entry) ", . - " __STRING (entry) "\n\t"
+#endif
+
+#define STRINGXP(X) __STRING (X)
+
+__asm__(\
+ ".text\n\
+ " _RTLD_PROLOGUE (_start) "\
+ mv a0, sp\n\
+ jal _dl_start\n\
+ # Stash user entry point in s0.\n\
+ mv s0, a0\n\
+ # See if we were run as a command with the executable file\n\
+ # name as an extra leading argument.\n\
+ lw a0, _dl_skip_args\n\
+ # Load the original argument count.\n\
+ " STRINGXP (REG_L) " a1, 0(sp)\n\
+ # Subtract _dl_skip_args from it.\n\
+ sub a1, a1, a0\n\
+ # Adjust the stack pointer to skip _dl_skip_args words.\n\
+ sll a0, a0, " STRINGXP (PTRLOG) "\n\
+ add sp, sp, a0\n\
+ # Save back the modified argument count.\n\
+ " STRINGXP (REG_S) " a1, 0(sp)\n\
+ # Pass our finalizer function to _start.\n\
+ lla a0, _dl_fini\n\
+ # Jump to the user entry point.\n\
+ jr s0\n\
+ " _RTLD_EPILOGUE (_start) "\
+ .previous" \
+);
+
+/* Get a pointer to the argv array. On many platforms this can be just
+ * the address of the first argument, on other platforms we need to
+ * do something a little more subtle here. */
+#define GET_ARGV(ARGVP, ARGS) ARGVP = (((unsigned long*)ARGS)+1)
+
+/* Function calls are not safe until the GOT relocations have been done. */
+#define NO_FUNCS_BEFORE_BOOTSTRAP
+
+/* Handle relocation of the symbols in the dynamic loader. */
+static __always_inline
+void PERFORM_BOOTSTRAP_RELOC(ELF_RELOC *rpnt, ElfW(Addr) *reloc_addr,
+ ElfW(Addr) symbol_addr, ElfW(Addr) load_addr, ElfW(Addr) *sym)
+{
+ switch (ELF_R_TYPE(rpnt->r_info)) {
+ case R_RISCV_NONE:
+ break;
+ case R_RISCV_JUMP_SLOT:
+ *reloc_addr = symbol_addr + rpnt->r_addend;
+ break;
+ default:
+ _dl_exit(1);
+ }
+}
+
+#define DL_UPDATE_LOADADDR_HDR(LOADADDR, ADDR, PHDR)
diff --git a/ldso/ldso/riscv32/dl-syscalls.h b/ldso/ldso/riscv32/dl-syscalls.h
new file mode 100644
index 000000000..f40c4fd31
--- /dev/null
+++ b/ldso/ldso/riscv32/dl-syscalls.h
@@ -0,0 +1 @@
+/* stub for arch-specific syscall issues */
diff --git a/ldso/ldso/riscv32/dl-sysdep.h b/ldso/ldso/riscv32/dl-sysdep.h
new file mode 100644
index 000000000..e0a59fddd
--- /dev/null
+++ b/ldso/ldso/riscv32/dl-sysdep.h
@@ -0,0 +1,91 @@
+/*
+ * Various assembly language/system dependent hacks that are required
+ * so that we can minimize the amount of platform specific code.
+ * Copyright (C) 2000-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2024 by Waldemar Brodkorb <wbx@uclibc-ng.org>
+ * Ported from GNU C Library
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/* Copyright (C) 2011-2019 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+/* Define this if the system uses RELOCA. */
+#define ELF_USES_RELOCA
+
+#include <elf.h>
+#include <link.h>
+
+/* Initialization sequence for the GOT. */
+#define INIT_GOT(GOT_BASE,MODULE) \
+{ \
+ GOT_BASE[2] = (unsigned long) _dl_linux_resolve; \
+ GOT_BASE[1] = (unsigned long) MODULE; \
+}
+
+/* Here we define the magic numbers that this dynamic loader should accept */
+#define MAGIC1 EM_RISCV
+#undef MAGIC2
+
+/* Used for error messages */
+#define ELF_TARGET "RISC-V"
+
+struct elf_resolve;
+unsigned long _dl_linux_resolver(struct elf_resolve * tpnt, int reloc_entry);
+
+#define ELF_MACHINE_JMP_SLOT R_RISCV_JUMP_SLOT
+
+#define elf_machine_type_class(type) \
+ ((ELF_RTYPE_CLASS_PLT * ((type) == ELF_MACHINE_JMP_SLOT \
+ || (__WORDSIZE == 32 && (type) == R_RISCV_TLS_DTPREL32) \
+ || (__WORDSIZE == 32 && (type) == R_RISCV_TLS_DTPMOD32) \
+ || (__WORDSIZE == 32 && (type) == R_RISCV_TLS_TPREL32) \
+ || (__WORDSIZE == 64 && (type) == R_RISCV_TLS_DTPREL64) \
+ || (__WORDSIZE == 64 && (type) == R_RISCV_TLS_DTPMOD64) \
+ || (__WORDSIZE == 64 && (type) == R_RISCV_TLS_TPREL64))) \
+ | (ELF_RTYPE_CLASS_COPY * ((type) == R_RISCV_COPY)))
+
+
+/* Return the link-time address of _DYNAMIC. */
+static inline ElfW(Addr)
+elf_machine_dynamic (void)
+{
+ extern ElfW(Addr) _GLOBAL_OFFSET_TABLE_ __attribute__ ((visibility ("hidden")));
+ return _GLOBAL_OFFSET_TABLE_;
+}
+
+
+/* Return the run-time load address of the shared object. */
+static __always_inline ElfW(Addr) __attribute__ ((unused))
+elf_machine_load_address (void)
+{
+ ElfW(Addr) load_addr;
+ __asm__ ("lla %0, _DYNAMIC" : "=r" (load_addr));
+ return load_addr - elf_machine_dynamic ();
+}
+
+static __always_inline void
+elf_machine_relative(Elf32_Addr load_off, const Elf32_Addr rel_addr,
+ Elf32_Word relative_count)
+{
+ Elf32_Rela *rpnt = (Elf32_Rela*)rel_addr;
+ --rpnt;
+ do {
+ Elf32_Addr *const reloc_addr = (Elf32_Addr*)(load_off + (++rpnt)->r_offset);
+
+ *reloc_addr = load_off + rpnt->r_addend;
+ } while (--relative_count);
+}
diff --git a/ldso/ldso/riscv32/elfinterp.c b/ldso/ldso/riscv32/elfinterp.c
new file mode 100644
index 000000000..dc1ac994d
--- /dev/null
+++ b/ldso/ldso/riscv32/elfinterp.c
@@ -0,0 +1,295 @@
+/* RISCV ELF shared library loader suppport
+ *
+ * Copyright (C) 2001-2004 Erik Andersen
+ * Copyright (C) 2024 Waldemar Brodkorb <wbx@uclibc-ng.org>
+ *
+ * All rights reserved.
+ *
+ * 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. The name of the above contributors may not be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE 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 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.
+ */
+
+/* Program to load an ELF binary on a linux system, and run it.
+ References to symbols in sharable libraries can be resolved by either
+ an ELF sharable library or a linux style of shared library. */
+
+#include "ldso.h"
+
+extern int _dl_linux_resolve(void);
+
+unsigned long _dl_linux_resolver(struct elf_resolve *tpnt, int reloc_entry)
+{
+ ELF_RELOC *this_reloc;
+ char *strtab;
+ ElfW(Sym) *symtab;
+ int symtab_index;
+ char *rel_addr;
+ char *new_addr;
+ char **got_addr;
+ ElfW(Addr) instr_addr;
+ char *symname;
+
+ rel_addr = (char *)tpnt->dynamic_info[DT_JMPREL];
+ this_reloc = (ELF_RELOC *)(rel_addr + reloc_entry);
+ symtab_index = ELF_R_SYM(this_reloc->r_info);
+
+ symtab = (ElfW(Sym) *)tpnt->dynamic_info[DT_SYMTAB];
+ strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
+ symname = strtab + symtab[symtab_index].st_name;
+
+ /* Address of jump instruction to fix up */
+ instr_addr = (this_reloc->r_offset + tpnt->loadaddr);
+ got_addr = (char **)instr_addr;
+
+ /* Get the address of the GOT entry */
+ new_addr = _dl_find_hash(symname, &_dl_loaded_modules->symbol_scope, tpnt, ELF_RTYPE_CLASS_PLT, NULL);
+ if (unlikely(!new_addr)) {
+ _dl_dprintf(2, "%s: can't resolve symbol '%s'\n", _dl_progname, symname);
+ _dl_exit(1);
+ }
+#if defined (__SUPPORT_LD_DEBUG__)
+ if (_dl_debug_bindings) {
+ _dl_dprintf(_dl_debug_file, "\nresolve function: %s", symname);
+ if (_dl_debug_detail) _dl_dprintf(_dl_debug_file,
+ "\tpatched %x ==> %x @ %x", *got_addr, new_addr, got_addr);
+ }
+ if (!_dl_debug_nofixups) {
+ *got_addr = new_addr;
+ }
+#else
+ *got_addr = new_addr;
+#endif
+ return (unsigned long)new_addr;
+}
+
+static int
+_dl_parse(struct elf_resolve *tpnt, struct r_scope_elem *scope,
+ unsigned long rel_addr, unsigned long rel_size,
+ int (*reloc_fnc) (struct elf_resolve *tpnt, struct r_scope_elem *scope,
+ ELF_RELOC *rpnt, ElfW(Sym) *symtab, char *strtab))
+{
+ unsigned int i;
+ char *strtab;
+ ElfW(Sym) *symtab;
+ ELF_RELOC *rpnt;
+ int symtab_index;
+
+ /* Parse the relocation information */
+ rpnt = (ELF_RELOC *)rel_addr;
+ rel_size = rel_size / sizeof(ELF_RELOC);
+
+ symtab = (ElfW(Sym) *)tpnt->dynamic_info[DT_SYMTAB];
+ strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
+
+ for (i = 0; i < rel_size; i++, rpnt++) {
+ int res;
+
+ symtab_index = ELF_R_SYM(rpnt->r_info);
+
+ debug_sym(symtab, strtab, symtab_index);
+ debug_reloc(symtab, strtab, rpnt);
+
+ res = reloc_fnc(tpnt, scope, rpnt, symtab, strtab);
+
+ if (res==0)
+ continue;
+
+ _dl_dprintf(2, "\n%s: ", _dl_progname);
+
+ if (symtab_index)
+ _dl_dprintf(2, "symbol '%s': ",
+ strtab + symtab[symtab_index].st_name);
+
+ if (unlikely(res < 0)) {
+ int reloc_type = ELF_R_TYPE(rpnt->r_info);
+ _dl_dprintf(2, "can't handle reloc type %x\n", reloc_type);
+ _dl_exit(-res);
+ } else if (unlikely(res > 0)) {
+ _dl_dprintf(2, "can't resolve symbol\n");
+ return res;
+ }
+ }
+
+ return 0;
+}
+
+static int
+_dl_do_reloc (struct elf_resolve *tpnt, struct r_scope_elem *scope,
+ ELF_RELOC *rpnt, ElfW(Sym) *symtab, char *strtab)
+{
+ int reloc_type;
+ int symtab_index;
+ char *symname;
+#if defined USE_TLS && USE_TLS
+ struct elf_resolve *tls_tpnt = NULL;
+#endif
+ struct symbol_ref sym_ref;
+ ElfW(Addr) *reloc_addr;
+ ElfW(Addr) symbol_addr;
+#if defined (__SUPPORT_LD_DEBUG__)
+ ElfW(Addr) old_val;
+#endif
+
+ reloc_addr = (ElfW(Addr)*)(tpnt->loadaddr + (unsigned long)rpnt->r_offset);
+ reloc_type = ELF_R_TYPE(rpnt->r_info);
+ symtab_index = ELF_R_SYM(rpnt->r_info);
+ sym_ref.sym = &symtab[symtab_index];
+ sym_ref.tpnt = NULL;
+ symbol_addr = 0;
+ symname = strtab + sym_ref.sym->st_name;
+
+ if (symtab_index) {
+ symbol_addr = (ElfW(Addr))_dl_find_hash(symname, scope, tpnt,
+ elf_machine_type_class(reloc_type), &sym_ref);
+
+ /*
+ * We want to allow undefined references to weak symbols - this might
+ * have been intentional. We should not be linking local symbols
+ * here, so all bases should be covered.
+ */
+ if (unlikely (!symbol_addr &&
+ (ELF_ST_TYPE(symtab[symtab_index].st_info) != STT_TLS) &&
+ (ELF_ST_BIND(symtab[symtab_index].st_info) != STB_WEAK))) {
+ return 1;
+ }
+ if (_dl_trace_prelink) {
+ _dl_debug_lookup (symname, tpnt, &symtab[symtab_index],
+ &sym_ref, elf_machine_type_class(reloc_type));
+ }
+#if defined USE_TLS && USE_TLS
+ tls_tpnt = sym_ref.tpnt;
+#endif
+ } else {
+ /*
+ * Relocs against STN_UNDEF are usually treated as using a
+ * symbol value of zero, and using the module containing the
+ * reloc itself.
+ */
+ symbol_addr = sym_ref.sym->st_value;
+#if defined USE_TLS && USE_TLS
+ tls_tpnt = tpnt;
+#endif
+ }
+
+#if defined (__SUPPORT_LD_DEBUG__)
+ old_val = *reloc_addr;
+#endif
+
+ switch (reloc_type) {
+ case R_RISCV_NONE:
+ break;
+ case R_RISCV_32: /* REL_SYMBOLIC */
+ case R_RISCV_JUMP_SLOT: /* REL_PLT */
+ *reloc_addr = symbol_addr + rpnt->r_addend;
+ break;
+ case R_RISCV_RELATIVE:
+ *reloc_addr += tpnt->loadaddr + rpnt->r_addend;
+ break;
+ case R_RISCV_COPY:
+ if (symbol_addr) {
+ _dl_memcpy((char *)reloc_addr, (char *)symbol_addr,
+ sym_ref.sym->st_size);
+ }
+ break;
+#if defined USE_TLS && USE_TLS
+ case R_RISCV_TLS_DTPMOD32:
+ *reloc_addr = tls_tpnt->l_tls_modid;
+ break;
+ case R_RISCV_TLS_DTPREL32:
+ *reloc_addr = symbol_addr + rpnt->r_addend;
+ break;
+ case R_RISCV_TLS_TPREL32:
+ CHECK_STATIC_TLS ((struct link_map *) tls_tpnt);
+ *reloc_addr = tls_tpnt->l_tls_offset + symbol_addr + rpnt->r_addend - TLS_TCB_SIZE;
+ break;
+#endif
+ default:
+ return -1; /*call _dl_exit(1) */
+ }
+
+#if defined (__SUPPORT_LD_DEBUG__)
+ if (_dl_debug_reloc && _dl_debug_detail) {
+ _dl_dprintf(_dl_debug_file, "\tpatched: %x ==> %x @ %x\n",
+ old_val, *reloc_addr, reloc_addr);
+ }
+#endif
+
+ return 0;
+}
+
+#undef __RISCV_LAZY_RELOC_WORKS
+#ifdef __RISCV_LAZY_RELOC_WORKS
+static int
+_dl_do_lazy_reloc (struct elf_resolve *tpnt, struct r_scope_elem *scope,
+ ELF_RELOC *rpnt, ElfW(Sym) *symtab, char *strtab)
+{
+ int reloc_type;
+ ElfW(Addr) *reloc_addr;
+#if defined (__SUPPORT_LD_DEBUG__)
+ ElfW(Addr) old_val;
+#endif
+
+ (void)scope;
+ (void)strtab;
+
+ reloc_addr = (ElfW(Addr)*)(tpnt->loadaddr + rpnt->r_offset);
+ reloc_type = ELF_R_TYPE(rpnt->r_info);
+
+#if defined (__SUPPORT_LD_DEBUG__)
+ old_val = *reloc_addr;
+#endif
+
+ switch (reloc_type) {
+ case R_RISCV_NONE:
+ break;
+ case R_RISCV_JUMP_SLOT:
+ break;
+ default:
+ return -1; /*call _dl_exit(1) */
+ }
+
+#if defined (__SUPPORT_LD_DEBUG__)
+ if (_dl_debug_reloc && _dl_debug_detail) {
+ _dl_dprintf(_dl_debug_file, "\tpatched_lazy: %x ==> %x @ %x\n",
+ old_val, *reloc_addr, reloc_addr);
+ }
+#endif
+
+ return 0;
+}
+#endif
+
+void _dl_parse_lazy_relocation_information(struct dyn_elf *rpnt,
+ unsigned long rel_addr, unsigned long rel_size)
+{
+#ifdef __RISCV_LAZY_RELOC_WORKS
+ (void)_dl_parse(rpnt->dyn, NULL, rel_addr, rel_size, _dl_do_lazy_reloc);
+#else
+ _dl_parse_relocation_information(rpnt, &_dl_loaded_modules->symbol_scope,
+ rel_addr, rel_size);
+#endif
+}
+
+int _dl_parse_relocation_information(struct dyn_elf *rpnt,
+ struct r_scope_elem *scope, unsigned long rel_addr, unsigned long rel_size)
+{
+ return _dl_parse(rpnt->dyn, scope, rel_addr, rel_size, _dl_do_reloc);
+}
diff --git a/ldso/ldso/riscv32/resolve.S b/ldso/ldso/riscv32/resolve.S
new file mode 100644
index 000000000..bfa91ecdb
--- /dev/null
+++ b/ldso/ldso/riscv32/resolve.S
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2024 by Waldemar Brodkorb <wbx@uclibc-ng.org>
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ * ported from GNU libc
+ */
+
+/* Copyright (C) 2017-2019 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library. If not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <features.h>
+
+#include <sysdep.h>
+#include <sys/asm.h>
+
+/* Assembler veneer called from the PLT header code for lazy loading.
+ The PLT header passes its own args in t0-t2. */
+
+#ifdef __riscv_float_abi_soft
+# define FRAME_SIZE (-((-10 * SZREG) & ALMASK))
+#else
+# define FRAME_SIZE (-((-10 * SZREG - 8 * SZFREG) & ALMASK))
+#endif
+
+ENTRY (_dl_linux_resolve)
+ # Save arguments to stack.
+ addi sp, sp, -FRAME_SIZE
+ REG_S ra, 9*SZREG(sp)
+ REG_S a0, 1*SZREG(sp)
+ REG_S a1, 2*SZREG(sp)
+ REG_S a2, 3*SZREG(sp)
+ REG_S a3, 4*SZREG(sp)
+ REG_S a4, 5*SZREG(sp)
+ REG_S a5, 6*SZREG(sp)
+ REG_S a6, 7*SZREG(sp)
+ REG_S a7, 8*SZREG(sp)
+
+#ifndef __riscv_float_abi_soft
+ FREG_S fa0, (10*SZREG + 0*SZFREG)(sp)
+ FREG_S fa1, (10*SZREG + 1*SZFREG)(sp)
+ FREG_S fa2, (10*SZREG + 2*SZFREG)(sp)
+ FREG_S fa3, (10*SZREG + 3*SZFREG)(sp)
+ FREG_S fa4, (10*SZREG + 4*SZFREG)(sp)
+ FREG_S fa5, (10*SZREG + 5*SZFREG)(sp)
+ FREG_S fa6, (10*SZREG + 6*SZFREG)(sp)
+ FREG_S fa7, (10*SZREG + 7*SZFREG)(sp)
+#endif
+
+ # Update .got.plt and obtain runtime address of callee.
+ slli a1, t1, 1
+ mv a0, t0 # link map
+ add a1, a1, t1 # reloc offset (== thrice the .got.plt offset)
+ la a2, _dl_fixup
+ jalr a2
+ mv t1, a0
+
+ # Restore arguments from stack.
+ REG_L ra, 9*SZREG(sp)
+ REG_L a0, 1*SZREG(sp)
+ REG_L a1, 2*SZREG(sp)
+ REG_L a2, 3*SZREG(sp)
+ REG_L a3, 4*SZREG(sp)
+ REG_L a4, 5*SZREG(sp)
+ REG_L a5, 6*SZREG(sp)
+ REG_L a6, 7*SZREG(sp)
+ REG_L a7, 8*SZREG(sp)
+
+#ifndef __riscv_float_abi_soft
+ FREG_L fa0, (10*SZREG + 0*SZFREG)(sp)
+ FREG_L fa1, (10*SZREG + 1*SZFREG)(sp)
+ FREG_L fa2, (10*SZREG + 2*SZFREG)(sp)
+ FREG_L fa3, (10*SZREG + 3*SZFREG)(sp)
+ FREG_L fa4, (10*SZREG + 4*SZFREG)(sp)
+ FREG_L fa5, (10*SZREG + 5*SZFREG)(sp)
+ FREG_L fa6, (10*SZREG + 6*SZFREG)(sp)
+ FREG_L fa7, (10*SZREG + 7*SZFREG)(sp)
+#endif
+
+ addi sp, sp, FRAME_SIZE
+
+ # Invoke the callee.
+ jr t1
+END (_dl_linux_resolve)
+