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.

24 files changed, 1170 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index ec0cce9c76..a7f4a36332 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,22 @@
 	* config.h.in: Regenerate.
 	* manual/platform.texi: Add RISC-V documenation for
 	__riscv_flush_icache.
+	* 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.
 
 2018-01-29  Florian Weimer  <fweimer@redhat.com>
 
diff --git a/sysdeps/riscv/__longjmp.S b/sysdeps/riscv/__longjmp.S
new file mode 100644
index 0000000000..0b9e5e10e2
--- /dev/null
+++ b/sysdeps/riscv/__longjmp.S
@@ -0,0 +1,57 @@
+/* longjmp, RISC-V version.
+   Copyright (C) 1996-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include <sys/asm.h>
+
+ENTRY (__longjmp)
+	REG_L ra,  0*SZREG(a0)
+	REG_L s0,  1*SZREG(a0)
+	REG_L s1,  2*SZREG(a0)
+	REG_L s2,  3*SZREG(a0)
+	REG_L s3,  4*SZREG(a0)
+	REG_L s4,  5*SZREG(a0)
+	REG_L s5,  6*SZREG(a0)
+	REG_L s6,  7*SZREG(a0)
+	REG_L s7,  8*SZREG(a0)
+	REG_L s8,  9*SZREG(a0)
+	REG_L s9, 10*SZREG(a0)
+	REG_L s10,11*SZREG(a0)
+	REG_L s11,12*SZREG(a0)
+	REG_L sp, 13*SZREG(a0)
+
+#ifndef __riscv_float_abi_soft
+	FREG_L fs0, 14*SZREG+ 0*SZFREG(a0)
+	FREG_L fs1, 14*SZREG+ 1*SZFREG(a0)
+	FREG_L fs2, 14*SZREG+ 2*SZFREG(a0)
+	FREG_L fs3, 14*SZREG+ 3*SZFREG(a0)
+	FREG_L fs4, 14*SZREG+ 4*SZFREG(a0)
+	FREG_L fs5, 14*SZREG+ 5*SZFREG(a0)
+	FREG_L fs6, 14*SZREG+ 6*SZFREG(a0)
+	FREG_L fs7, 14*SZREG+ 7*SZFREG(a0)
+	FREG_L fs8, 14*SZREG+ 8*SZFREG(a0)
+	FREG_L fs9, 14*SZREG+ 9*SZFREG(a0)
+	FREG_L fs10,14*SZREG+10*SZFREG(a0)
+	FREG_L fs11,14*SZREG+11*SZFREG(a0)
+#endif
+
+	seqz a0, a1
+	add  a0, a0, a1   # a0 = (a1 == 0) ? 1 : a1
+	ret
+
+END (__longjmp)
diff --git a/sysdeps/riscv/backtrace.c b/sysdeps/riscv/backtrace.c
new file mode 100644
index 0000000000..27ce597b39
--- /dev/null
+++ b/sysdeps/riscv/backtrace.c
@@ -0,0 +1 @@
+#include <sysdeps/x86_64/backtrace.c>
diff --git a/sysdeps/riscv/bits/endian.h b/sysdeps/riscv/bits/endian.h
new file mode 100644
index 0000000000..4aaf559d4f
--- /dev/null
+++ b/sysdeps/riscv/bits/endian.h
@@ -0,0 +1,5 @@
+#ifndef _ENDIAN_H
+# error "Never use <bits/endian.h> directly; include <endian.h> instead."
+#endif
+
+#define __BYTE_ORDER __LITTLE_ENDIAN
diff --git a/sysdeps/riscv/bits/link.h b/sysdeps/riscv/bits/link.h
new file mode 100644
index 0000000000..cedc4ad9b2
--- /dev/null
+++ b/sysdeps/riscv/bits/link.h
@@ -0,0 +1,56 @@
+/* Machine-specific declarations for dynamic linker interface.  RISC-V version.
+   Copyright (C) 2005-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef	_LINK_H
+# error "Never include <bits/link.h> directly; use <link.h> instead."
+#endif
+
+typedef struct La_riscv_regs
+{
+  unsigned long int lr_reg[8]; /* a0 - a7 */
+  double lr_fpreg[8]; /* fa0 - fa7 */
+  unsigned long int lr_ra;
+  unsigned long int lr_sp;
+} La_riscv_regs;
+
+/* Return values for calls from PLT on RISC-V.  */
+typedef struct La_riscv_retval
+{
+  unsigned long int lrv_a0;
+  unsigned long int lrv_a1;
+  double lrv_fa0;
+  double lrv_fa1;
+} La_riscv_retval;
+
+__BEGIN_DECLS
+
+extern ElfW(Addr) la_riscv_gnu_pltenter (ElfW(Sym) *__sym, unsigned int __ndx,
+					 uintptr_t *__refcook,
+					 uintptr_t *__defcook,
+					 La_riscv_regs *__regs,
+					 unsigned int *__flags,
+					 const char *__symname,
+					 long int *__framesizep);
+extern unsigned int la_riscv_gnu_pltexit (ElfW(Sym) *__sym, unsigned int __ndx,
+					  uintptr_t *__refcook,
+					  uintptr_t *__defcook,
+					  const La_riscv_regs *__inregs,
+					  La_riscv_retval *__outregs,
+					  const char *__symname);
+
+__END_DECLS
diff --git a/sysdeps/riscv/bits/setjmp.h b/sysdeps/riscv/bits/setjmp.h
new file mode 100644
index 0000000000..988ad6b1d6
--- /dev/null
+++ b/sysdeps/riscv/bits/setjmp.h
@@ -0,0 +1,39 @@
+/* Define the machine-dependent type `jmp_buf'.  RISC-V version.
+   Copyright (C) 2011-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _RISCV_BITS_SETJMP_H
+#define _RISCV_BITS_SETJMP_H
+
+typedef struct __jmp_buf_internal_tag
+  {
+    /* Program counter.  */
+    long int __pc;
+    /* Callee-saved registers.  */
+    long int __regs[12];
+    /* Stack pointer.  */
+    long int __sp;
+
+    /* Callee-saved floating point registers.  */
+#if defined __riscv_float_abi_double
+   double __fpregs[12];
+#elif !defined __riscv_float_abi_soft
+# error unsupported FLEN
+#endif
+  } __jmp_buf[1];
+
+#endif /* _RISCV_BITS_SETJMP_H */
diff --git a/sysdeps/riscv/bits/wordsize.h b/sysdeps/riscv/bits/wordsize.h
new file mode 100644
index 0000000000..67a16ba622
--- /dev/null
+++ b/sysdeps/riscv/bits/wordsize.h
@@ -0,0 +1,29 @@
+/* Determine the wordsize from the preprocessor defines.  RISC-V version.
+   Copyright (C) 2002-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#if __riscv_xlen == (__SIZEOF_POINTER__ * 8)
+# define __WORDSIZE __riscv_xlen
+#else
+# error unsupported ABI
+#endif
+
+#if __riscv_xlen == 64
+# define __WORDSIZE_TIME64_COMPAT32 1
+#else
+# error "rv32i-based targets are not supported"
+#endif
diff --git a/sysdeps/riscv/bsd-_setjmp.c b/sysdeps/riscv/bsd-_setjmp.c
new file mode 100644
index 0000000000..0d413101ce
--- /dev/null
+++ b/sysdeps/riscv/bsd-_setjmp.c
@@ -0,0 +1 @@
+/* _setjmp is implemented in setjmp.S */
diff --git a/sysdeps/riscv/bsd-setjmp.c b/sysdeps/riscv/bsd-setjmp.c
new file mode 100644
index 0000000000..ee7c5e3437
--- /dev/null
+++ b/sysdeps/riscv/bsd-setjmp.c
@@ -0,0 +1 @@
+/* setjmp is implemented in setjmp.S */
diff --git a/sysdeps/riscv/dl-machine.h b/sysdeps/riscv/dl-machine.h
new file mode 100644
index 0000000000..9e3c2925f0
--- /dev/null
+++ b/sysdeps/riscv/dl-machine.h
@@ -0,0 +1,323 @@
+/* Machine-dependent ELF dynamic relocation inline functions.  RISC-V version.
+   Copyright (C) 2011-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef dl_machine_h
+#define dl_machine_h
+
+#define ELF_MACHINE_NAME "RISC-V"
+
+#include <entry.h>
+#include <elf/elf.h>
+#include <sys/asm.h>
+#include <dl-tls.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 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)))
+
+#define ELF_MACHINE_NO_REL 1
+#define ELF_MACHINE_NO_RELA 0
+
+/* Return nonzero iff ELF header is compatible with the running host.  */
+static inline int __attribute_used__
+elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
+{
+  /* We can only run RISC-V binaries.  */
+  if (ehdr->e_machine != EM_RISCV)
+    return 0;
+
+  /* Ensure the library's floating-point ABI matches that of the running
+     system.  For now we don't support mixing XLEN, so there's no need (or way)
+     to check it matches.  */
+#ifdef __riscv_float_abi_double
+  if ((ehdr->e_flags & EF_RISCV_FLOAT_ABI) != EF_RISCV_FLOAT_ABI_DOUBLE)
+    return 0;
+#else
+  if ((ehdr->e_flags & EF_RISCV_FLOAT_ABI) != EF_RISCV_FLOAT_ABI_SOFT)
+    return 0;
+#endif
+
+  return 1;
+}
+
+/* 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_;
+}
+
+#define STRINGXP(X) __STRING (X)
+#define STRINGXV(X) STRINGV_ (X)
+#define STRINGV_(...) # __VA_ARGS__
+
+/* Return the run-time load address of the shared object.  */
+static inline ElfW(Addr)
+elf_machine_load_address (void)
+{
+  ElfW(Addr) load_addr;
+  asm ("lla %0, _DYNAMIC" : "=r" (load_addr));
+  return load_addr - elf_machine_dynamic ();
+}
+
+/* Initial entry point code for the dynamic linker.
+   The C function `_dl_start' is the real entry point;
+   its return value is the user program's entry point.  */
+
+#define RTLD_START asm (\
+	".text\n\
+	" _RTLD_PROLOGUE (ENTRY_POINT) "\
+	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\
+	# Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\
+	" STRINGXP (REG_L) " a0, _rtld_local\n\
+	add a2, sp, " STRINGXP (SZREG) "\n\
+	sll a3, a1, " STRINGXP (PTRLOG) "\n\
+	add a3, a3, a2\n\
+	add a3, a3, " STRINGXP (SZREG) "\n\
+	# Call the function to run the initializers.\n\
+	jal _dl_init\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 (ENTRY_POINT) "\
+	.previous" \
+);
+
+/* Names of the architecture-specific auditing callback functions.  */
+#define ARCH_LA_PLTENTER riscv_gnu_pltenter
+#define ARCH_LA_PLTEXIT riscv_gnu_pltexit
+
+/* Bias .got.plt entry by the offset requested by the PLT header.  */
+#define elf_machine_plt_value(map, reloc, value) (value)
+
+static inline ElfW(Addr)
+elf_machine_fixup_plt (struct link_map *map, lookup_t t,
+		       const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
+		       const ElfW(Rela) *reloc,
+		       ElfW(Addr) *reloc_addr, ElfW(Addr) value)
+{
+  return *reloc_addr = value;
+}
+
+#endif /* !dl_machine_h */
+
+#ifdef RESOLVE_MAP
+
+/* Perform a relocation described by R_INFO at the location pointed to
+   by RELOC_ADDR.  SYM is the relocation symbol specified by R_INFO and
+   MAP is the object containing the reloc.  */
+
+auto inline void
+__attribute__ ((always_inline))
+elf_machine_rela (struct link_map *map, const ElfW(Rela) *reloc,
+		  const ElfW(Sym) *sym, const struct r_found_version *version,
+		  void *const reloc_addr, int skip_ifunc)
+{
+  ElfW(Addr) r_info = reloc->r_info;
+  const unsigned long int r_type = ELFW (R_TYPE) (r_info);
+  ElfW(Addr) *addr_field = (ElfW(Addr) *) reloc_addr;
+  const ElfW(Sym) *const __attribute__ ((unused)) refsym = sym;
+  struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
+  ElfW(Addr) value = 0;
+  if (sym_map != NULL)
+    value = sym_map->l_addr + sym->st_value + reloc->r_addend;
+
+  switch (r_type)
+    {
+#ifndef RTLD_BOOTSTRAP
+    case __WORDSIZE == 64 ? R_RISCV_TLS_DTPMOD64 : R_RISCV_TLS_DTPMOD32:
+      if (sym_map)
+	*addr_field = sym_map->l_tls_modid;
+      break;
+
+    case __WORDSIZE == 64 ? R_RISCV_TLS_DTPREL64 : R_RISCV_TLS_DTPREL32:
+      if (sym != NULL)
+	*addr_field = TLS_DTPREL_VALUE (sym) + reloc->r_addend;
+      break;
+
+    case __WORDSIZE == 64 ? R_RISCV_TLS_TPREL64 : R_RISCV_TLS_TPREL32:
+      if (sym != NULL)
+	{
+	  CHECK_STATIC_TLS (map, sym_map);
+	  *addr_field = TLS_TPREL_VALUE (sym_map, sym) + reloc->r_addend;
+	}
+      break;
+
+    case R_RISCV_COPY:
+      {
+	if (__glibc_unlikely (sym == NULL))
+	  /* This can happen in trace mode if an object could not be
+	     found.  */
+	  break;
+
+	/* Handle TLS copy relocations.  */
+	if (__glibc_unlikely (ELFW (ST_TYPE) (sym->st_info) == STT_TLS))
+	  {
+	    /* There's nothing to do if the symbol is in .tbss.  */
+	    if (__glibc_likely (sym->st_value >= sym_map->l_tls_initimage_size))
+	      break;
+	    value += (ElfW(Addr)) sym_map->l_tls_initimage - sym_map->l_addr;
+	  }
+
+	size_t size = sym->st_size;
+	if (__glibc_unlikely (sym->st_size != refsym->st_size))
+	  {
+	    const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
+	    if (sym->st_size > refsym->st_size)
+	      size = refsym->st_size;
+	    if (sym->st_size > refsym->st_size || GLRO(dl_verbose))
+	      _dl_error_printf ("\
+  %s: Symbol `%s' has different size in shared object, consider re-linking\n",
+				rtld_progname ?: "<program name unknown>",
+				strtab + refsym->st_name);
+	  }
+
+	memcpy (reloc_addr, (void *)value, size);
+	break;
+      }
+#endif
+
+#if !defined RTLD_BOOTSTRAP || !defined HAVE_Z_COMBRELOC
+    case R_RISCV_RELATIVE:
+      {
+# if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC
+	/* This is defined in rtld.c, but nowhere in the static libc.a;
+	   make the reference weak so static programs can still link.
+	   This declaration cannot be done when compiling rtld.c
+	   (i.e. #ifdef RTLD_BOOTSTRAP) because rtld.c contains the
+	   common defn for _dl_rtld_map, which is incompatible with a
+	   weak decl in the same file.  */
+#  ifndef SHARED
+	weak_extern (GL(dl_rtld_map));
+#  endif
+	if (map != &GL(dl_rtld_map)) /* Already done in rtld itself.  */
+# endif
+	  *addr_field = map->l_addr + reloc->r_addend;
+      break;
+    }
+#endif
+
+    case R_RISCV_JUMP_SLOT:
+    case __WORDSIZE == 64 ? R_RISCV_64 : R_RISCV_32:
+      *addr_field = value;
+      break;
+
+    case R_RISCV_NONE:
+      break;
+
+    default:
+      _dl_reloc_bad_type (map, r_type, 0);
+      break;
+    }
+}
+
+auto inline void
+__attribute__ ((always_inline))
+elf_machine_rela_relative (ElfW(Addr) l_addr, const ElfW(Rela) *reloc,
+			  void *const reloc_addr)
+{
+  *(ElfW(Addr) *) reloc_addr = l_addr + reloc->r_addend;
+}
+
+auto inline void
+__attribute__ ((always_inline))
+elf_machine_lazy_rel (struct link_map *map, ElfW(Addr) l_addr,
+		      const ElfW(Rela) *reloc, int skip_ifunc)
+{
+  ElfW(Addr) *const reloc_addr = (void *) (l_addr + reloc->r_offset);
+  const unsigned int r_type = ELFW (R_TYPE) (reloc->r_info);
+
+  /* Check for unexpected PLT reloc type.  */
+  if (__glibc_likely (r_type == R_RISCV_JUMP_SLOT))
+    {
+      if (__glibc_unlikely (map->l_mach.plt == 0))
+	{
+	  if (l_addr)
+	    *reloc_addr += l_addr;
+	}
+      else
+	*reloc_addr = map->l_mach.plt;
+    }
+  else
+    _dl_reloc_bad_type (map, r_type, 1);
+}
+
+/* Set up the loaded object described by L so its stub function
+   will jump to the on-demand fixup code __dl_runtime_resolve.  */
+
+auto inline int
+__attribute__ ((always_inline))
+elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
+{
+#ifndef RTLD_BOOTSTRAP
+  /* If using PLTs, fill in the first two entries of .got.plt.  */
+  if (l->l_info[DT_JMPREL])
+    {
+      extern void _dl_runtime_resolve (void) __attribute__ ((visibility ("hidden")));
+      ElfW(Addr) *gotplt = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]);
+      /* If a library is prelinked but we have to relocate anyway,
+	 we have to be able to undo the prelinking of .got.plt.
+	 The prelinker saved the address of .plt for us here.  */
+      if (gotplt[1])
+	l->l_mach.plt = gotplt[1] + l->l_addr;
+      gotplt[0] = (ElfW(Addr)) &_dl_runtime_resolve;
+      gotplt[1] = (ElfW(Addr)) l;
+    }
+#endif
+
+  return lazy;
+}
+
+#endif /* RESOLVE_MAP */
diff --git a/sysdeps/riscv/dl-trampoline.S b/sysdeps/riscv/dl-trampoline.S
new file mode 100644
index 0000000000..cda3be9f4e
--- /dev/null
+++ b/sysdeps/riscv/dl-trampoline.S
@@ -0,0 +1,90 @@
+/* RISC-V PLT trampoline
+   Copyright (C) 2017-2018 Free Software Foundation, Inc.
+
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#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_runtime_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_runtime_resolve)
diff --git a/sysdeps/riscv/gccframe.h b/sysdeps/riscv/gccframe.h
new file mode 100644
index 0000000000..3dc62863af
--- /dev/null
+++ b/sysdeps/riscv/gccframe.h
@@ -0,0 +1,21 @@
+/* Definition of object in frame unwind info.  RISC-V version.
+   Copyright (C) 2001-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#define FIRST_PSEUDO_REGISTER 66
+
+#include <sysdeps/generic/gccframe.h>
diff --git a/sysdeps/riscv/jmpbuf-offsets.h b/sysdeps/riscv/jmpbuf-offsets.h
new file mode 100644
index 0000000000..fff4d0d9c6
--- /dev/null
+++ b/sysdeps/riscv/jmpbuf-offsets.h
@@ -0,0 +1,23 @@
+/* Private macros for accessing __jmp_buf contents.  RISC-V version.
+   Copyright (C) 2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <jmpbuf-unwind.h>
+
+/* Helper for generic ____longjmp_chk().  */
+#define JB_FRAME_ADDRESS(buf) \
+  ((void *) _jmpbuf_sp (buf))
diff --git a/sysdeps/riscv/jmpbuf-unwind.h b/sysdeps/riscv/jmpbuf-unwind.h
new file mode 100644
index 0000000000..2e5f37f102
--- /dev/null
+++ b/sysdeps/riscv/jmpbuf-unwind.h
@@ -0,0 +1,46 @@
+/* Examine __jmp_buf for unwinding frames.  RISC-V version.
+   Copyright (C) 2003-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <setjmp.h>
+#include <stdint.h>
+#include <unwind.h>
+#include <sysdep.h>
+
+/* Test if longjmp to JMPBUF would unwind the frame
+   containing a local variable at ADDRESS.  */
+#define _JMPBUF_UNWINDS(jmpbuf, address, demangle)		\
+  ((void *) (address) < (void *) demangle ((jmpbuf)[0].__sp))
+
+#define _JMPBUF_CFA_UNWINDS_ADJ(_jmpbuf, _context, _adj) \
+  _JMPBUF_UNWINDS_ADJ (_jmpbuf, (void *) _Unwind_GetCFA (_context), _adj)
+
+static inline uintptr_t __attribute__ ((unused))
+_jmpbuf_sp (__jmp_buf regs)
+{
+  uintptr_t sp = regs[0].__sp;
+#ifdef PTR_DEMANGLE
+  PTR_DEMANGLE (sp);
+#endif
+  return sp;
+}
+
+#define _JMPBUF_UNWINDS_ADJ(_jmpbuf, _address, _adj) \
+  ((uintptr_t) (_address) - (_adj) < _jmpbuf_sp (_jmpbuf) - (_adj))
+
+/* We use the normal longjmp for unwinding.  */
+#define __libc_unwind_longjmp(buf, val) __libc_longjmp (buf, val)
diff --git a/sysdeps/riscv/ldsodefs.h b/sysdeps/riscv/ldsodefs.h
new file mode 100644
index 0000000000..c032b73a9c
--- /dev/null
+++ b/sysdeps/riscv/ldsodefs.h
@@ -0,0 +1,47 @@
+/* Run-time dynamic linker data structures for loaded ELF shared objects.
+   Copyright (C) 2011-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _RISCV_LDSODEFS_H
+#define _RISCV_LDSODEFS_H 1
+
+#include <elf.h>
+
+struct La_riscv_regs;
+struct La_riscv_retval;
+
+#define ARCH_PLTENTER_MEMBERS						\
+    ElfW(Addr) (*riscv_gnu_pltenter) (ElfW(Sym) *, unsigned int,	\
+				      uintptr_t *, uintptr_t *,		\
+				      const struct La_riscv_regs *,	\
+				      unsigned int *, const char *name,	\
+				      long int *framesizep);
+
+#define ARCH_PLTEXIT_MEMBERS						\
+    unsigned int (*riscv_gnu_pltexit) (ElfW(Sym) *, unsigned int,	\
+				       uintptr_t *, uintptr_t *,	\
+				       const struct La_riscv_regs *,	\
+				       struct La_riscv_retval *,	\
+				       const char *);
+
+/* The RISC-V ABI specifies that the dynamic section has to be read-only.  */
+
+#define DL_RO_DYN_SECTION 1
+
+#include_next <ldsodefs.h>
+
+#endif
diff --git a/sysdeps/riscv/linkmap.h b/sysdeps/riscv/linkmap.h
new file mode 100644
index 0000000000..ac170bb342
--- /dev/null
+++ b/sysdeps/riscv/linkmap.h
@@ -0,0 +1,4 @@
+struct link_map_machine
+  {
+    ElfW(Addr) plt; /* Address of .plt.  */
+  };
diff --git a/sysdeps/riscv/machine-gmon.h b/sysdeps/riscv/machine-gmon.h
new file mode 100644
index 0000000000..a50d50a2e1
--- /dev/null
+++ b/sysdeps/riscv/machine-gmon.h
@@ -0,0 +1,37 @@
+/* RISC-V definitions for profiling support.
+   Copyright (C) 1996-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+/* Accept 'frompc' address as argument from the function that calls
+   _mcount for profiling.  Use  __builtin_return_address (0)
+   for the 'selfpc' address.  */
+
+#include <sysdep.h>
+
+static void mcount_internal (unsigned long int frompc,
+			     unsigned long int selfpc);
+
+#define _MCOUNT_DECL(frompc, selfpc) \
+static inline void mcount_internal (unsigned long int frompc, \
+unsigned long int selfpc)
+
+#define MCOUNT								\
+void _mcount (void *frompc)						\
+{									\
+  mcount_internal ((unsigned long int) frompc,				\
+		   (unsigned long int) RETURN_ADDRESS (0));		\
+}
diff --git a/sysdeps/riscv/memusage.h b/sysdeps/riscv/memusage.h
new file mode 100644
index 0000000000..a29e0d1e03
--- /dev/null
+++ b/sysdeps/riscv/memusage.h
@@ -0,0 +1,21 @@
+/* Machine-specific definitions for memory usage profiling, RISC-V version.
+   Copyright (C) 2000-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#define GETSP() ({ register uintptr_t stack_ptr asm ("sp"); stack_ptr; })
+
+#include <sysdeps/generic/memusage.h>
diff --git a/sysdeps/riscv/setjmp.S b/sysdeps/riscv/setjmp.S
new file mode 100644
index 0000000000..cfbd276fc3
--- /dev/null
+++ b/sysdeps/riscv/setjmp.S
@@ -0,0 +1,74 @@
+/* setjmp for RISC-V.
+   Copyright (C) 1996-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include <sys/asm.h>
+
+ENTRY (_setjmp)
+  li	a1, 0
+  j	__sigsetjmp
+END (_setjmp)
+ENTRY (setjmp)
+  li	a1, 1
+  /* Fallthrough */
+END (setjmp)
+ENTRY (__sigsetjmp)
+	REG_S ra,  0*SZREG(a0)
+	REG_S s0,  1*SZREG(a0)
+	REG_S s1,  2*SZREG(a0)
+	REG_S s2,  3*SZREG(a0)
+	REG_S s3,  4*SZREG(a0)
+	REG_S s4,  5*SZREG(a0)
+	REG_S s5,  6*SZREG(a0)
+	REG_S s6,  7*SZREG(a0)
+	REG_S s7,  8*SZREG(a0)
+	REG_S s8,  9*SZREG(a0)
+	REG_S s9, 10*SZREG(a0)
+	REG_S s10,11*SZREG(a0)
+	REG_S s11,12*SZREG(a0)
+	REG_S sp, 13*SZREG(a0)
+
+#ifndef __riscv_float_abi_soft
+	FREG_S fs0, 14*SZREG+ 0*SZFREG(a0)
+	FREG_S fs1, 14*SZREG+ 1*SZFREG(a0)
+	FREG_S fs2, 14*SZREG+ 2*SZFREG(a0)
+	FREG_S fs3, 14*SZREG+ 3*SZFREG(a0)
+	FREG_S fs4, 14*SZREG+ 4*SZFREG(a0)
+	FREG_S fs5, 14*SZREG+ 5*SZFREG(a0)
+	FREG_S fs6, 14*SZREG+ 6*SZFREG(a0)
+	FREG_S fs7, 14*SZREG+ 7*SZFREG(a0)
+	FREG_S fs8, 14*SZREG+ 8*SZFREG(a0)
+	FREG_S fs9, 14*SZREG+ 9*SZFREG(a0)
+	FREG_S fs10,14*SZREG+10*SZFREG(a0)
+	FREG_S fs11,14*SZREG+11*SZFREG(a0)
+#endif
+
+#if !IS_IN (libc) && IS_IN (rtld)
+  /* In ld.so we never save the signal mask.  */
+  li a0, 0
+  ret
+#else
+  /* Make a tail call to __sigjmp_save; it takes the same args.  */
+  j __sigjmp_save
+#endif
+
+
+END (__sigsetjmp)
+
+hidden_def (__sigsetjmp)
+weak_alias (_setjmp, __GI__setjmp)
diff --git a/sysdeps/riscv/sotruss-lib.c b/sysdeps/riscv/sotruss-lib.c
new file mode 100644
index 0000000000..f35b554db5
--- /dev/null
+++ b/sysdeps/riscv/sotruss-lib.c
@@ -0,0 +1,51 @@
+/* Override generic sotruss-lib.c to define actual functions for RISC-V.
+   Copyright (C) 2012-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#define HAVE_ARCH_PLTENTER
+#define HAVE_ARCH_PLTEXIT
+
+#include <elf/sotruss-lib.c>
+
+ElfW(Addr)
+la_riscv_gnu_pltenter (ElfW(Sym) *sym __attribute__ ((unused)),
+		       unsigned int ndx __attribute__ ((unused)),
+		       uintptr_t *refcook, uintptr_t *defcook,
+		       La_riscv_regs *regs, unsigned int *flags,
+		       const char *symname, long int *framesizep)
+{
+  print_enter (refcook, defcook, symname,
+	       regs->lr_reg[0], regs->lr_reg[1], regs->lr_reg[2],
+	       *flags);
+
+  /* No need to copy anything, we will not need the parameters in any case.  */
+  *framesizep = 0;
+
+  return sym->st_value;
+}
+
+unsigned int
+la_riscv_gnu_pltexit (ElfW(Sym) *sym, unsigned int ndx, uintptr_t *refcook,
+		      uintptr_t *defcook,
+		      const struct La_riscv_regs *inregs,
+		      struct La_riscv_retval *outregs,
+		      const char *symname)
+{
+  print_exit (refcook, defcook, symname, outregs->lrv_a0);
+
+  return 0;
+}
diff --git a/sysdeps/riscv/start.S b/sysdeps/riscv/start.S
new file mode 100644
index 0000000000..4635ddb5eb
--- /dev/null
+++ b/sysdeps/riscv/start.S
@@ -0,0 +1,81 @@
+/* Startup code compliant to the ELF RISC-V ABI.
+   Copyright (C) 1995-2018 Free Software Foundation, Inc.
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#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)
+	call  .Lload_gp
+	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. */
+	lla   a3, __libc_csu_init
+	lla   a4, __libc_csu_fini
+	mv    a6, sp  /* stack_end.  */
+
+	tail  __libc_start_main@plt
+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.  */
+
+.Lload_gp:
+.option push
+.option norelax
+	lla   gp, __global_pointer$
+.option pop
+	ret
+
+	.section .preinit_array,"aw"
+	.dc.a .Lload_gp
+
+/* Define a symbol for the first piece of initialized data.  */
+	.data
+	.globl __data_start
+__data_start:
+	.weak data_start
+	data_start = __data_start
diff --git a/sysdeps/riscv/sys/asm.h b/sysdeps/riscv/sys/asm.h
new file mode 100644
index 0000000000..ddb84b683b
--- /dev/null
+++ b/sysdeps/riscv/sys/asm.h
@@ -0,0 +1,63 @@
+/* Miscellaneous macros.
+   Copyright (C) 2000-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_ASM_H
+#define _SYS_ASM_H
+
+/* Macros to handle different pointer/register sizes for 32/64-bit code.  */
+#if __riscv_xlen == 64
+# define PTRLOG 3
+# define SZREG	8
+# define REG_S sd
+# define REG_L ld
+#elif __riscv_xlen == 32
+# error "rv32i-based targets are not supported"
+#else
+# error __riscv_xlen must equal 32 or 64
+#endif
+
+#if !defined __riscv_float_abi_soft
+/* For ABI uniformity, reserve 8 bytes for floats, even if double-precision
+   floating-point is not supported in hardware.  */
+# if defined __riscv_float_abi_double
+#  define FREG_L fld
+#  define FREG_S fsd
+#  define SZFREG 8
+# else
+#  error unsupported FLEN
+# endif
+#endif
+
+/* Declare leaf routine.  */
+#define	LEAF(symbol)				\
+		.globl	symbol;			\
+		.align	2;			\
+		.type	symbol,@function;	\
+symbol:						\
+		cfi_startproc;
+
+/* Mark end of function.  */
+#undef END
+#define END(function)				\
+		cfi_endproc;			\
+		.size	function,.-function
+
+/* Stack alignment.  */
+#define ALMASK	~15
+
+#endif /* sys/asm.h */
diff --git a/sysdeps/riscv/tls-macros.h b/sysdeps/riscv/tls-macros.h
new file mode 100644
index 0000000000..5433ed9d16
--- /dev/null
+++ b/sysdeps/riscv/tls-macros.h
@@ -0,0 +1,61 @@
+/* Macros to support TLS testing in times of missing compiler support.
+   Copyright (C) 2017-2018 Free Software Foundation, Inc.
+
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+
+#include <sys/cdefs.h>
+#include <sys/asm.h>
+#include <sysdep.h>
+#include "dl-tls.h"
+
+#define LOAD_GP						\
+	".option push\n\t"				\
+	".option norelax\n\t"				\
+	"la gp, __global_pointer$\n\t"			\
+	".option pop\n\t"
+
+#define UNLOAD_GP
+
+#define TLS_GD(x)					\
+	({ void *__result;				\
+	asm (LOAD_GP					\
+	     "la.tls.gd %0, " #x "\n\t"			\
+	     UNLOAD_GP					\
+	     : "=r" (__result));			\
+	__tls_get_addr (__result); })
+
+#define TLS_LD(x) TLS_GD(x)
+
+#define TLS_IE(x)					\
+	({ void *__result;				\
+	asm (LOAD_GP					\
+	     "la.tls.ie %0, " #x "\n\t"			\
+	     "add %0, %0, tp\n\t"			\
+	     UNLOAD_GP					\
+	     : "=r" (__result));			\
+	__result; })
+
+#define TLS_LE(x)					\
+	({ void *__result;				\
+	asm (LOAD_GP					\
+	     "lui %0, %%tprel_hi(" #x ")\n\t"		\
+	     "add %0, %0, tp, %%tprel_add(" #x ")\n\t"	\
+	     "addi %0, %0, %%tprel_lo(" #x ")\n\t"	\
+	     UNLOAD_GP					\
+	     : "=r" (__result));			\
+	__result; })
diff --git a/sysdeps/riscv/tst-audit.h b/sysdeps/riscv/tst-audit.h
new file mode 100644
index 0000000000..7cce56d104
--- /dev/null
+++ b/sysdeps/riscv/tst-audit.h
@@ -0,0 +1,23 @@
+/* Definitions for testing PLT entry/exit auditing.  RISC-V version.
+   Copyright (C) 2005-2018 Free Software Foundation, Inc.
+   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.
+
+   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
+   <http://www.gnu.org/licenses/>.  */
+
+#define pltenter la_riscv_gnu_pltenter
+#define pltexit la_riscv_gnu_pltexit
+#define La_regs La_riscv_regs
+#define La_retval La_riscv_retval
+#define int_retval lrv_a0