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RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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/* Startup code compliant to the ELF RISC-V ABI.
Update copyright dates with scripts/update-copyrights I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2021-01-02 20:32:25 +01:00
Copyright (C) 1995-2021 Free Software Foundation, Inc.
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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This file is part of the GNU C Library.
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.
In addition to the permissions in the GNU Lesser General Public
License, the Free Software Foundation gives you unlimited
permission to link the compiled version of this file with other
programs, and to distribute those programs without any restriction
coming from the use of this file. (The GNU Lesser General Public
License restrictions do apply in other respects; for example, they
cover modification of the file, and distribution when not linked
into another program.)
Note that people who make modified versions of this file are not
obligated to grant this special exception for their modified
versions; it is their choice whether to do so. The GNU Lesser
General Public License gives permission to release a modified
version without this exception; this exception also makes it
possible to release a modified version which carries forward this
exception.
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
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
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<https://www.gnu.org/licenses/>. */
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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#define __ASSEMBLY__ 1
#include <entry.h>
#include <sysdep.h>
#include <sys/asm.h>
/* The entry point's job is to call __libc_start_main. Per the ABI,
a0 contains the address of a function to be passed to atexit.
__libc_start_main wants this in a5. */
ENTRY (ENTRY_POINT)
RISC-V: properly terminate call chain (bug 23125) Mark the ra register as undefined in _start, so that unwinding through main works correctly. Also, don't use a tail call so that ra points after the call to __libc_start_main, not after the previous call.
2018-09-25 11:11:27 +02:00
/* Terminate call stack by noting ra is undefined. Use a dummy
.cfi_label to force starting the FDE. */
.cfi_label .Ldummy
cfi_undefined (ra)
sysdeps/riscv/start.S: rename .Lload_gp to load_gp (bug 24376) Renaming the symbol keeps the label in the symbol table as a normal local label, so that `objdump -d' can pick it up as an anchor.
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call load_gp
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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mv a5, a0 /* rtld_fini. */
/* main may be in a shared library. */
la a0, main
REG_L a1, 0(sp) /* argc. */
addi a2, sp, SZREG /* argv. */
andi sp, sp, ALMASK /* Align stack. */
Reduce the statically linked startup code [BZ #23323] It turns out the startup code in csu/elf-init.c has a perfect pair of ROP gadgets (see Marco-Gisbert and Ripoll-Ripoll, "return-to-csu: A New Method to Bypass 64-bit Linux ASLR"). These functions are not needed in dynamically-linked binaries because DT_INIT/DT_INIT_ARRAY are already processed by the dynamic linker. However, the dynamic linker skipped the main program for some reason. For maximum backwards compatibility, this is not changed, and instead, the main map is consulted from __libc_start_main if the init function argument is a NULL pointer. For statically linked binaries, the old approach based on linker symbols is still used because there is nothing else available. A new symbol version __libc_start_main@@GLIBC_2.34 is introduced because new binaries running on an old libc would not run their ELF constructors, leading to difficult-to-debug issues.
2021-02-25 12:10:57 +01:00
li a3, 0 /* Used to be init. */
li a4, 0 /* Used to be fini. */
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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mv a6, sp /* stack_end. */
RISC-V: properly terminate call chain (bug 23125) Mark the ra register as undefined in _start, so that unwinding through main works correctly. Also, don't use a tail call so that ra points after the call to __libc_start_main, not after the previous call.
2018-09-25 11:11:27 +02:00
call __libc_start_main@plt
ebreak
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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END (ENTRY_POINT)
/* Dynamic links need the global pointer to be initialized prior to calling
any shared library's initializers, so we use preinit_array to load it.
This doesn't cut it for static links, though, since the global pointer
needs to be initialized before calling __libc_start_main in that case.
So we redundantly initialize it at the beginning of _start. */
sysdeps/riscv/start.S: rename .Lload_gp to load_gp (bug 24376) Renaming the symbol keeps the label in the symbol table as a normal local label, so that `objdump -d' can pick it up as an anchor.
2019-08-12 11:29:29 +02:00
load_gp:
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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.option push
.option norelax
lla gp, __global_pointer$
.option pop
ret
.section .preinit_array,"aw"
sysdeps/riscv/start.S: rename .Lload_gp to load_gp (bug 24376) Renaming the symbol keeps the label in the symbol table as a normal local label, so that `objdump -d' can pick it up as an anchor.
2019-08-12 11:29:29 +02:00
.dc.a load_gp
RISC-V: ABI Implementation This patch contains code that needs to directly know about the RISC-V ABI, which is specified in a work-in-progress psABI document: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md This is meant to contain all the RISC-V code that needs to explicitly name registers or manage in-memory structure layout. This does not contain any of the Linux-specific code. 2018-01-29 Palmer Dabbelt <palmer@sifive.com> * sysdeps/riscv/__longjmp.S: New file. * sysdeps/riscv/backtrace.c: Likewise. * sysdeps/riscv/bits/endian.h: Likewise. * sysdeps/riscv/bits/setjmp.h: Likewise. * sysdeps/riscv/bits/wordsize.h: Likewise. * sysdeps/riscv/bsd-_setjmp.c: Likewise. * sysdeps/riscv/bsd-setjmp.c: Likewise. * sysdeps/riscv/dl-trampoline.S: Likewise. * sysdeps/riscv/gccframe.h: Likewise. * sysdeps/riscv/jmpbuf-offsets.h: Likewise. * sysdeps/riscv/jmpbuf-unwind.h: Likewise. * sysdeps/riscv/machine-gmon.h: Likewise. * sysdeps/riscv/memusage.h: Likewise. * sysdeps/riscv/setjmp.S: Likewise. * sysdeps/riscv/sys/asm.h: Likewise. * sysdeps/riscv/tls-macros.h: Likewise.
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/* Define a symbol for the first piece of initialized data. */
.data
.globl __data_start
__data_start:
.weak data_start
data_start = __data_start
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