Add support for RISC-V

This implements initial support for the RISC-V architecture.  It has
been tested with qemu linux-user emulation
<https://build.opensuse.org/package/live_build_log/openSUSE:Factory:RISCV/elfutils/standard/riscv64>,
with the following unresolved issues

FAIL: run-strip-strmerge.sh
===========================

elflint /home/abuild/rpmbuild/BUILD/elfutils-0.170/tests/elfstrmerge
section [32] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x51c0 does not match .got section address 0x5010
section [32] '.symtab': symbol 119: st_value out of bounds
FAIL run-strip-strmerge.sh (exit status: 1)

FAIL: run-elflint-self.sh
=========================

section [33] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x6220 does not match .got section address 0x6008
section [33] '.symtab': symbol 135: st_value out of bounds
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/addr2line
section [33] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x91d8 does not match .got section address 0x9040
section [33] '.symtab': symbol 163: st_value out of bounds
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elfcmp
section [33] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x1a2a0 does not match .got section address 0x1a040
section [33] '.symtab': symbol 267: st_value out of bounds
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint
section [33] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0xd418 does not match .got section address 0xd0f0
section [33] '.symtab': symbol 238: st_value out of bounds
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/nm
section [33] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0xa2d0 does not match .got section address 0xa0b0
section [33] '.symtab': symbol 193: st_value out of bounds
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/objdump
section [33] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x2e5b8 does not match .got section address 0x2e058
section [33] '.symtab': symbol 410: st_value out of bounds
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/readelf
section [32] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x171b8 does not match .got section address 0x17010
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/libelf/libelf.so
section [32] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0x3a5b0 does not match .got section address 0x3a0d8
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/libdw/libdw.so
section [31] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0xd0c8 does not match .got section address 0xd008
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/backends/libebl_i386.so
section [31] '.symtab': _GLOBAL_OFFSET_TABLE_ symbol value 0xf0c8 does not match .got section address 0xf008
*** failure in /home/abuild/rpmbuild/BUILD/elfutils-0.170/src/elflint --quiet --gnu-ld /home/abuild/rpmbuild/BUILD/elfutils-0.170/backends/libebl_x86_64.so
FAIL run-elflint-self.sh (exit status: 1)

FAIL: run-native-test.sh
========================

/home/abuild/rpmbuild/BUILD/elfutils-0.170/tests/allregs: dwfl_module_register_names: no backend registers known
FAIL run-native-test.sh (exit status: 1)

FAIL: run-backtrace-native-core.sh
==================================

backtrace: backtrace.c:111: callback_verify: Assertion `symname && strcmp (symname, "raise") == 0' failed.
./test-subr.sh: line 84: 26040 Aborted                 (core dumped) LD_LIBRARY_PATH="${built_library_path}${LD_LIBRARY_PATH:+:}$LD_LIBRARY_PATH" $VALGRIND_CMD "$@"
backtrace-child-core.26027: no main
rmdir: failed to remove 'test-26016': Directory not empty
FAIL run-backtrace-native-core.sh (exit status: 1)

In addition, all tests that use ptrace are failing as linux-user
emulation does not implement it.

There are no regressions for a x86_64 build.

Signed-off-by: Andreas Schwab <[email protected]>

1 files changed, 62 insertions, 0 deletions

diff --git a/backends/riscv_symbol.c b/backends/riscv_symbol.c
new file mode 100644
index 00000000..628e0572
--- /dev/null
+++ b/backends/riscv_symbol.c
@@ -0,0 +1,62 @@
+/* RISC-V specific symbolic name handling.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils 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
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <elf.h>
+#include <stddef.h>
+#include <string.h>
+
+#define BACKEND riscv_
+#include "libebl_CPU.h"
+
+
+/* Check for the simple reloc types.  */
+Elf_Type
+riscv_reloc_simple_type (Ebl *ebl __attribute__ ((unused)), int type)
+{
+  switch (type)
+    {
+    case R_RISCV_32:
+      return ELF_T_WORD;
+    case R_RISCV_64:
+      return ELF_T_XWORD;
+    default:
+      return ELF_T_NUM;
+    }
+}
+
+/* Check whether machine flags are valid.  */
+bool
+riscv_machine_flag_check (GElf_Word flags)
+{
+  return ((flags &~ (EF_RISCV_RVC
+		     | EF_RISCV_FLOAT_ABI)) == 0);
+}