Re: [PATCH v4 04/13] LoongArch: ABI Implementation

[Fangrui Song <maskray@google.com>]

On 2022-05-09, caiyinyu wrote:
>---
> sysdeps/loongarch/__longjmp.S                |  52 +++
> sysdeps/loongarch/bits/endianness.h          |  11 +
> sysdeps/loongarch/bits/link.h                |  58 +++
> sysdeps/loongarch/bits/setjmp.h              |  42 +++
> sysdeps/loongarch/bsd-_setjmp.c              |   1 +
> sysdeps/loongarch/bsd-setjmp.c               |   1 +
> sysdeps/loongarch/dl-machine.h               | 362 +++++++++++++++++++
> sysdeps/loongarch/dl-trampoline.S            |  91 +++++
> sysdeps/loongarch/jmpbuf-offsets.h           |  22 ++
> sysdeps/loongarch/jmpbuf-unwind.h            |  45 +++
> sysdeps/loongarch/ldsodefs.h                 |  41 +++
> sysdeps/loongarch/linkmap.h                  |  22 ++
> sysdeps/loongarch/machine-gmon.h             |  37 ++
> sysdeps/loongarch/setjmp.S                   |  66 ++++
> sysdeps/loongarch/sotruss-lib.c              |  50 +++
> sysdeps/loongarch/start.S                    |  67 ++++
> sysdeps/loongarch/sys/asm.h                  |  59 +++
> sysdeps/loongarch/tst-audit.h                |  23 ++
> sysdeps/unix/sysv/linux/loongarch/ldconfig.h |  26 ++
> 19 files changed, 1076 insertions(+)
> create mode 100644 sysdeps/loongarch/__longjmp.S
> create mode 100644 sysdeps/loongarch/bits/endianness.h
> create mode 100644 sysdeps/loongarch/bits/link.h
> create mode 100644 sysdeps/loongarch/bits/setjmp.h
> create mode 100644 sysdeps/loongarch/bsd-_setjmp.c
> create mode 100644 sysdeps/loongarch/bsd-setjmp.c
> create mode 100644 sysdeps/loongarch/dl-machine.h
> create mode 100644 sysdeps/loongarch/dl-trampoline.S
> create mode 100644 sysdeps/loongarch/jmpbuf-offsets.h
> create mode 100644 sysdeps/loongarch/jmpbuf-unwind.h
> create mode 100644 sysdeps/loongarch/ldsodefs.h
> create mode 100644 sysdeps/loongarch/linkmap.h
> create mode 100644 sysdeps/loongarch/machine-gmon.h
> create mode 100644 sysdeps/loongarch/setjmp.S
> create mode 100644 sysdeps/loongarch/sotruss-lib.c
> create mode 100644 sysdeps/loongarch/start.S
> create mode 100644 sysdeps/loongarch/sys/asm.h
> create mode 100644 sysdeps/loongarch/tst-audit.h
> create mode 100644 sysdeps/unix/sysv/linux/loongarch/ldconfig.h
>
>diff --git a/sysdeps/loongarch/__longjmp.S b/sysdeps/loongarch/__longjmp.S
>new file mode 100644
>index 0000000000..b7690dd94f
>--- /dev/null
>+++ b/sysdeps/loongarch/__longjmp.S
>@@ -0,0 +1,52 @@
>+/* longjmp.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#include <sysdep.h>
>+#include <sys/asm.h>
>+
>+ENTRY (__longjmp)
>+	REG_L ra, a0, 0*SZREG
>+	REG_L sp, a0, 1*SZREG
>+	REG_L x,  a0, 2*SZREG
>+	REG_L fp, a0, 3*SZREG
>+	REG_L s0, a0, 4*SZREG
>+	REG_L s1, a0, 5*SZREG
>+	REG_L s2, a0, 6*SZREG
>+	REG_L s3, a0, 7*SZREG
>+	REG_L s4, a0, 8*SZREG
>+	REG_L s5, a0, 9*SZREG
>+	REG_L s6, a0, 10*SZREG
>+	REG_L s7, a0, 11*SZREG
>+	REG_L s8, a0, 12*SZREG
>+
>+#ifndef __loongarch_soft_float
>+	FREG_L $f24, a0, 13*SZREG + 0*SZFREG
>+	FREG_L $f25, a0, 13*SZREG + 1*SZFREG
>+	FREG_L $f26, a0, 13*SZREG + 2*SZFREG
>+	FREG_L $f27, a0, 13*SZREG + 3*SZFREG
>+	FREG_L $f28, a0, 13*SZREG + 4*SZFREG
>+	FREG_L $f29, a0, 13*SZREG + 5*SZFREG
>+	FREG_L $f30, a0, 13*SZREG + 6*SZFREG
>+	FREG_L $f31, a0, 13*SZREG + 7*SZFREG
>+#endif
>+
>+	sltui	a0,a1,1
>+	ADD	a0, a0, a1	 # a0 = (a1 == 0) ? 1 : a1
>+	jirl	zero,ra,0
>+
>+END (__longjmp)
>diff --git a/sysdeps/loongarch/bits/endianness.h b/sysdeps/loongarch/bits/endianness.h
>new file mode 100644
>index 0000000000..7290be7b18
>--- /dev/null
>+++ b/sysdeps/loongarch/bits/endianness.h
>@@ -0,0 +1,11 @@
>+#ifndef _BITS_ENDIANNESS_H
>+#define _BITS_ENDIANNESS_H 1
>+
>+#ifndef _BITS_ENDIAN_H
>+#error "Never use <bits/endianness.h> directly; include <endian.h> instead."
>+#endif
>+
>+/* LoongArch is little-endian.  */
>+#define __BYTE_ORDER __LITTLE_ENDIAN
>+
>+#endif /* bits/endianness.h */
>diff --git a/sysdeps/loongarch/bits/link.h b/sysdeps/loongarch/bits/link.h
>new file mode 100644
>index 0000000000..4df09989cb
>--- /dev/null
>+++ b/sysdeps/loongarch/bits/link.h
>@@ -0,0 +1,58 @@
>+/* Machine-specific declarations for dynamic linker interface.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#ifndef _LINK_H
>+#error "Never include <bits/link.h> directly; use <link.h> instead."
>+#endif
>+
>+typedef struct La_loongarch_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_loongarch_regs;
>+
>+/* Return values for calls from PLT on LoongArch.  */
>+typedef struct La_loongarch_retval
>+{
>+  unsigned long int lrv_a0;
>+  unsigned long int lrv_a1;
>+  double lrv_fa0;
>+  double lrv_fa1;
>+} La_loongarch_retval;
>+
>+__BEGIN_DECLS
>+
>+extern ElfW (Addr) la_loongarch_gnu_pltenter (ElfW (Sym) * __sym,
>+					      unsigned int __ndx,
>+					      uintptr_t *__refcook,
>+					      uintptr_t *__defcook,
>+					      La_loongarch_regs *__regs,
>+					      unsigned int *__flags,
>+					      const char *__symname,
>+					      long int *__framesizep);
>+extern unsigned int la_loongarch_gnu_pltexit (ElfW (Sym) * __sym,
>+					      unsigned int __ndx,
>+					      uintptr_t *__refcook,
>+					      uintptr_t *__defcook,
>+					      const La_loongarch_regs *__inregs,
>+					      La_loongarch_retval *__outregs,
>+					      const char *__symname);
>+
>+__END_DECLS
>diff --git a/sysdeps/loongarch/bits/setjmp.h b/sysdeps/loongarch/bits/setjmp.h
>new file mode 100644
>index 0000000000..8b323ad2b6
>--- /dev/null
>+++ b/sysdeps/loongarch/bits/setjmp.h
>@@ -0,0 +1,42 @@
>+/* Define the machine-dependent type `jmp_buf'.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#ifndef _LOONGARCH_BITS_SETJMP_H
>+#define _LOONGARCH_BITS_SETJMP_H
>+
>+typedef struct __jmp_buf_internal_tag
>+{
>+  /* Program counter.  */
>+  long int __pc;
>+  /* Stack pointer.  */
>+  long int __sp;
>+  /* Reserved */
>+  long int __x;
>+  /* Frame pointer.  */
>+  long int __fp;
>+  /* Callee-saved registers.  */
>+  long int __regs[9];
>+
>+#ifndef __loongarch_soft_float
>+  /* Callee-saved floating point registers.  */
>+  double __fpregs[8];
>+#endif
>+
>+} __jmp_buf[1];
>+
>+#endif /* _LOONGARCH_BITS_SETJMP_H */
>diff --git a/sysdeps/loongarch/bsd-_setjmp.c b/sysdeps/loongarch/bsd-_setjmp.c
>new file mode 100644
>index 0000000000..32f49441c3
>--- /dev/null
>+++ b/sysdeps/loongarch/bsd-_setjmp.c
>@@ -0,0 +1 @@
>+/* _setjmp is implemented in setjmp.S.  */
>diff --git a/sysdeps/loongarch/bsd-setjmp.c b/sysdeps/loongarch/bsd-setjmp.c
>new file mode 100644
>index 0000000000..45fd802aac
>--- /dev/null
>+++ b/sysdeps/loongarch/bsd-setjmp.c
>@@ -0,0 +1 @@
>+/* setjmp is implemented in setjmp.S.  */
>diff --git a/sysdeps/loongarch/dl-machine.h b/sysdeps/loongarch/dl-machine.h
>new file mode 100644
>index 0000000000..68b68e677d
>--- /dev/null
>+++ b/sysdeps/loongarch/dl-machine.h
>@@ -0,0 +1,362 @@
>+/* Machine-dependent ELF dynamic relocation inline functions.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#ifndef dl_machine_h
>+#define dl_machine_h
>+
>+#define ELF_MACHINE_NAME "LoongArch"
>+
>+#include <entry.h>
>+#include <elf/elf.h>
>+#include <sys/asm.h>
>+#include <dl-tls.h>
>+#include <dl-static-tls.h>
>+#include <dl-machine-rel.h>
>+
>+#ifndef _RTLD_PROLOGUE
>+# define _RTLD_PROLOGUE(entry)					\
>+	".globl\t" __STRING (entry) "\n\t"			\
>+	".type\t" __STRING (entry) ", @function\n\t"		\
>+	CFI_STARTPROC "\n"					\
>+	__STRING (entry) ":\n"
>+#endif
>+
>+#ifndef _RTLD_EPILOGUE
>+# define _RTLD_EPILOGUE(entry)					\
>+	CFI_ENDPROC "\n\t"					\
>+	".size\t" __STRING (entry) ", . - " __STRING (entry) "\n"
>+#endif
>+
>+#define ELF_MACHINE_JMP_SLOT R_LARCH_JUMP_SLOT
>+#define ELF_MACHINE_IRELATIVE R_LARCH_IRELATIVE
>+
>+#define elf_machine_type_class(type)				\
>+  ((ELF_RTYPE_CLASS_PLT * ((type) == ELF_MACHINE_JMP_SLOT	\
>+     || (__WORDSIZE == 32 && (type) == R_LARCH_TLS_DTPREL32)	\
>+     || (__WORDSIZE == 32 && (type) == R_LARCH_TLS_DTPMOD32)	\
>+     || (__WORDSIZE == 32 && (type) == R_LARCH_TLS_TPREL32)	\
>+     || (__WORDSIZE == 64 && (type) == R_LARCH_TLS_DTPREL64)	\
>+     || (__WORDSIZE == 64 && (type) == R_LARCH_TLS_DTPMOD64)	\
>+     || (__WORDSIZE == 64 && (type) == R_LARCH_TLS_TPREL64)))	\
>+   | (ELF_RTYPE_CLASS_COPY * ((type) == R_LARCH_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 LoongArch binaries.  */
>+  if (ehdr->e_machine != EM_LOONGARCH)
>+    return 0;
>+
>+  return 1;
>+}
>+
>+/* Runtime address of .got */
>+#define _GLOBAL_OFFSET_TABLE_ \
>+  ({ \
>+    ElfW (Addr) * r; \
>+    asm("la.pcrel %0, _GLOBAL_OFFSET_TABLE_" : "=r"(r)); \
>+    r; \
>+  })
>+
>+/* Return the link-time address of _DYNAMIC.  */
>+static inline ElfW (Addr) elf_machine_dynamic (void)
>+{
>+  return _GLOBAL_OFFSET_TABLE_[0];
>+}
>+
>+#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) got_linktime_addr;
>+  asm("la.got %0, _GLOBAL_OFFSET_TABLE_"
>+      /* Link-time address in GOT entry before runtime relocation */
>+      : "=r"(got_linktime_addr));
>+  return (ElfW (Addr)) _GLOBAL_OFFSET_TABLE_ - got_linktime_addr;
>+}
>+
>+/* 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) "\
>+      .cfi_label .Ldummy   \n\
>+      " CFI_UNDEFINED (1) "   \n\
>+      or	$a0, $sp, $zero   \n\
>+      bl	_dl_start   \n\
>+      # Stash user entry point in s0.   \n\
>+      or	$s0, $v0, $zero   \n\
>+      # See if we were run as a command with the executable file   \n\
>+      # name as an extra leading argument.   \n\
>+      la	$a0, _dl_skip_args   \n\
>+      ld.w	$a0, $a0, 0   \n\
>+      # Load the original argument count.   \n\
>+      ld.d	$a1, $sp, 0   \n\
>+      # Subtract _dl_skip_args from it.   \n\
>+      sub.d	$a1, $a1, $a0   \n\
>+      # Adjust the stack pointer to skip _dl_skip_args words.   \n\
>+      slli.d	$a0, $a0, 3   \n\
>+      add.d	$sp, $sp, $a0   \n\
>+      # Save back the modified argument count.   \n\
>+      st.d	$a1, $sp, 0   \n\
>+      # Call _dl_init (struct link_map *main_map, int argc, char **argv, \
>+		       char **env)    \n\
>+      la	$a0, _rtld_local   \n\
>+      ld.d	$a0, $a0, 0   \n\
>+      addi.d	$a2, $sp, 8   \n\
>+      slli.d	$a3, $a1, 3   \n\
>+      add.d	$a3, $a3, $a2   \n\
>+      addi.d	$a3, $a3, 8   \n\
>+      # Adjust $sp for 16-aligned   \n\
>+      srli.d  $t0, $sp, 4   \n\
>+      slli.d  $t0, $t0, 4   \n\
>+      ori	$t1, $sp, 0   \n\
>+      addi.d  $sp, $t0, -32   \n\
>+      st.d	$t1, $sp, 24   \n\
>+      # Call the function to run the initializers.   \n\
>+      bl	_dl_init   \n\
>+      # Pass our finalizer function to _start.   \n\
>+      ld.d    $sp, $sp, 24   \n\
>+      la	$a0, _dl_fini   \n\
>+      # Jump to the user entry point.   \n\
>+      jirl	$zero, $s0, 0   \n\
>+      " _RTLD_EPILOGUE (ENTRY_POINT) "\
>+      .previous");
>+
>+/* Names of the architecture-specific auditing callback functions.  */
>+#define ARCH_LA_PLTENTER loongarch_gnu_pltenter
>+#define ARCH_LA_PLTEXIT loongarch_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.  */
>+
>+static inline void __attribute__ ((always_inline))
>+elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
>+		  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 (map, scope, &sym, version, r_type);
>+  ElfW (Addr) value = 0;
>+  if (sym_map != NULL)
>+    value = SYMBOL_ADDRESS (sym_map, sym, true) + reloc->r_addend;
>+
>+  if (sym != NULL
>+      && __builtin_expect (ELFW (ST_TYPE) (sym->st_info) == STT_GNU_IFUNC, 0)
>+      && __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
>+      && __builtin_expect (!skip_ifunc, 1))
>+    value = ((ElfW (Addr) (*) (int)) value) (GLRO (dl_hwcap));
>+
>+  switch (r_type)
>+    {
>+#ifndef RTLD_BOOTSTRAP
>+    case __WORDSIZE == 64 ? R_LARCH_TLS_DTPMOD64:
>+    R_LARCH_TLS_DTPMOD32:
>+      if (sym_map)
>+	*addr_field = sym_map->l_tls_modid;
>+      break;
>+
>+    case __WORDSIZE == 64 ? R_LARCH_TLS_DTPREL64:
>+    R_LARCH_TLS_DTPREL32:
>+      if (sym != NULL)
>+	*addr_field = TLS_DTPREL_VALUE (sym) + reloc->r_addend;
>+      break;
>+
>+    case __WORDSIZE == 64 ? R_LARCH_TLS_TPREL64:
>+    R_LARCH_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_LARCH_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;
>+	  }

Please don't copy TLS copy relocations from riscv. It was a mistake:
https://sourceware.org/bugzilla/show_bug.cgi?id=23825

>+	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_LARCH_RELATIVE:

I have recently removed HAVE_Z_COMBRELOC. Please remove it here.

>+      {
>+#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_LARCH_JUMP_SLOT:
>+    case __WORDSIZE == 64 ? R_LARCH_64:
>+    R_LARCH_32:
>+      *addr_field = value;
>+      break;
>+
>+    case R_LARCH_IRELATIVE:
>+      value = map->l_addr + reloc->r_addend;
>+      if (__glibc_likely (!skip_ifunc))
>+	value = ((ElfW (Addr) (*) (void)) value) ();
>+      *addr_field = value;
>+      break;
>+
>+    case R_LARCH_NONE:
>+      break;
>+    default:
>+      _dl_reloc_bad_type (map, r_type, 0);
>+      break;
>+    }
>+}
>+
>+static 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;
>+}
>+
>+static inline void __attribute__ ((always_inline))
>+elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
>+		      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_LARCH_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 if (__glibc_unlikely (r_type == R_LARCH_IRELATIVE))
>+    {
>+      ElfW (Addr) *value = (void *) (l_addr + reloc->r_addend);
>+      if (__glibc_likely (!skip_ifunc))
>+	value = (ElfW (Addr) *) ((ElfW (Addr) (*) (void)) value) ();
>+      *reloc_addr = (ElfW (Addr)) value;
>+    }
>+  else
>+    _dl_reloc_bad_type (map, r_type, 1);
>+}

If you can ensure ld doesn't place IRELATIVE in .rela.plt, you can drop
IRELATIVE check in this function.

>+/* Set up the loaded object described by L so its stub function
>+   will jump to the on-demand fixup code __dl_runtime_resolve.  */
>+
>+static inline int __attribute__ ((always_inline))
>+elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
>+			   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.  */

prelink has been deprecated and will be removed. You can drop complexity
here and avoid mentioning prelink.

>+      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/loongarch/dl-trampoline.S b/sysdeps/loongarch/dl-trampoline.S
>new file mode 100644
>index 0000000000..eb610392f6
>--- /dev/null
>+++ b/sysdeps/loongarch/dl-trampoline.S
>@@ -0,0 +1,91 @@
>+/* PLT trampolines.
>+   Copyright (C) 2022 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
>+   <https://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 __loongarch_soft_float
>+# 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, sp, 9*SZREG
>+	REG_S	a0, sp, 1*SZREG
>+	REG_S	a1, sp, 2*SZREG
>+	REG_S	a2, sp, 3*SZREG
>+	REG_S	a3, sp, 4*SZREG
>+	REG_S	a4, sp, 5*SZREG
>+	REG_S	a5, sp, 6*SZREG
>+	REG_S	a6, sp, 7*SZREG
>+	REG_S	a7, sp, 8*SZREG
>+
>+#ifndef __loongarch_soft_float
>+	FREG_S	fa0, sp, 10*SZREG + 0*SZFREG
>+	FREG_S	fa1, sp, 10*SZREG + 1*SZFREG
>+	FREG_S	fa2, sp, 10*SZREG + 2*SZFREG
>+	FREG_S	fa3, sp, 10*SZREG + 3*SZFREG
>+	FREG_S	fa4, sp, 10*SZREG + 4*SZFREG
>+	FREG_S	fa5, sp, 10*SZREG + 5*SZFREG
>+	FREG_S	fa6, sp, 10*SZREG + 6*SZFREG
>+	FREG_S	fa7, sp, 10*SZREG + 7*SZFREG
>+#endif
>+
>+	/* Update .got.plt and obtain runtime address of callee */
>+	SLLI	a1, t1, 1
>+	or	a0, t0, zero
>+	ADD	a1, a1, t1
>+	la	a2, _dl_fixup
>+	jirl	ra, a2, 0
>+	or	t1, v0, zero
>+
>+	/* Restore arguments from stack. */
>+	REG_L	ra, sp, 9*SZREG
>+	REG_L	a0, sp, 1*SZREG
>+	REG_L	a1, sp, 2*SZREG
>+	REG_L	a2, sp, 3*SZREG
>+	REG_L	a3, sp, 4*SZREG
>+	REG_L	a4, sp, 5*SZREG
>+	REG_L	a5, sp, 6*SZREG
>+	REG_L	a6, sp, 7*SZREG
>+	REG_L	a7, sp, 8*SZREG
>+
>+#ifndef __loongarch_soft_float
>+	FREG_L	fa0, sp, 10*SZREG + 0*SZFREG
>+	FREG_L	fa1, sp, 10*SZREG + 1*SZFREG
>+	FREG_L	fa2, sp, 10*SZREG + 2*SZFREG
>+	FREG_L	fa3, sp, 10*SZREG + 3*SZFREG
>+	FREG_L	fa4, sp, 10*SZREG + 4*SZFREG
>+	FREG_L	fa5, sp, 10*SZREG + 5*SZFREG
>+	FREG_L	fa6, sp, 10*SZREG + 6*SZFREG
>+	FREG_L	fa7, sp, 10*SZREG + 7*SZFREG
>+#endif
>+
>+	ADDI	sp, sp, FRAME_SIZE
>+
>+	/* Invoke the callee. */
>+	jirl		zero, t1, 0
>+END (_dl_runtime_resolve)
>diff --git a/sysdeps/loongarch/jmpbuf-offsets.h b/sysdeps/loongarch/jmpbuf-offsets.h
>new file mode 100644
>index 0000000000..a4b8ea690e
>--- /dev/null
>+++ b/sysdeps/loongarch/jmpbuf-offsets.h
>@@ -0,0 +1,22 @@
>+/* Private macros for accessing __jmp_buf contents.
>+   Copyright (C) 2022 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
>+   <https://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/loongarch/jmpbuf-unwind.h b/sysdeps/loongarch/jmpbuf-unwind.h
>new file mode 100644
>index 0000000000..6fa509151d
>--- /dev/null
>+++ b/sysdeps/loongarch/jmpbuf-unwind.h
>@@ -0,0 +1,45 @@
>+/* Examine __jmp_buf for unwinding frames.
>+   Copyright (C) 2022 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
>+   <https://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/loongarch/ldsodefs.h b/sysdeps/loongarch/ldsodefs.h
>new file mode 100644
>index 0000000000..36b1b25b9f
>--- /dev/null
>+++ b/sysdeps/loongarch/ldsodefs.h
>@@ -0,0 +1,41 @@
>+/* Run-time dynamic linker data structures for loaded ELF shared objects.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#ifndef _LOONGARCH_LDSODEFS_H
>+#define _LOONGARCH_LDSODEFS_H 1
>+
>+#include <elf.h>
>+
>+struct La_loongarch_regs;
>+struct La_loongarch_retval;
>+
>+#define ARCH_PLTENTER_MEMBERS \
>+  ElfW (Addr) (*loongarch_gnu_pltenter) (ElfW (Sym) *, unsigned int, \
>+					 uintptr_t *, uintptr_t *, \
>+					 const struct La_loongarch_regs *, \
>+					 unsigned int *, const char *name, \
>+					 long int *framesizep);
>+
>+#define ARCH_PLTEXIT_MEMBERS \
>+  unsigned int (*loongarch_gnu_pltexit) (ElfW (Sym) *, unsigned int, \
>+		uintptr_t *, uintptr_t *, const struct La_loongarch_regs *, \
>+		struct La_loongarch_retval *, const char *);
>+
>+#include_next <ldsodefs.h>
>+
>+#endif
>diff --git a/sysdeps/loongarch/linkmap.h b/sysdeps/loongarch/linkmap.h
>new file mode 100644
>index 0000000000..bbba73ed70
>--- /dev/null
>+++ b/sysdeps/loongarch/linkmap.h
>@@ -0,0 +1,22 @@
>+/* Definition of link_map_machine.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+struct link_map_machine
>+{
>+  ElfW (Addr) plt; /* Address of .plt.  */
>+};
>diff --git a/sysdeps/loongarch/machine-gmon.h b/sysdeps/loongarch/machine-gmon.h
>new file mode 100644
>index 0000000000..4a3cdd964e
>--- /dev/null
>+++ b/sysdeps/loongarch/machine-gmon.h
>@@ -0,0 +1,37 @@
>+/* LoongArch definitions for profiling support.
>+   Copyright (C) 2022 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
>+   <https://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/loongarch/setjmp.S b/sysdeps/loongarch/setjmp.S
>new file mode 100644
>index 0000000000..b93ae2f5da
>--- /dev/null
>+++ b/sysdeps/loongarch/setjmp.S
>@@ -0,0 +1,66 @@
>+/* setjmp for LoongArch.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#include <sysdep.h>
>+#include <sys/asm.h>
>+
>+ENTRY (_setjmp)
>+	li.w		a1,0
>+	b		__sigsetjmp
>+END (_setjmp)
>+
>+ENTRY (setjmp)
>+	li.w		a1,1
>+END (setjmp)
>+
>+ENTRY (__sigsetjmp)
>+	REG_S ra, a0, 0*SZREG
>+	REG_S sp, a0, 1*SZREG
>+	REG_S x,  a0, 2*SZREG
>+	REG_S fp, a0, 3*SZREG
>+	REG_S s0, a0, 4*SZREG
>+	REG_S s1, a0, 5*SZREG
>+	REG_S s2, a0, 6*SZREG
>+	REG_S s3, a0, 7*SZREG
>+	REG_S s4, a0, 8*SZREG
>+	REG_S s5, a0, 9*SZREG
>+	REG_S s6, a0, 10*SZREG
>+	REG_S s7, a0, 11*SZREG
>+	REG_S s8, a0, 12*SZREG
>+
>+#ifndef __loongarch_soft_float
>+	FREG_S $f24, a0, 13*SZREG + 0*SZFREG
>+	FREG_S $f25, a0, 13*SZREG + 1*SZFREG
>+	FREG_S $f26, a0, 13*SZREG + 2*SZFREG
>+	FREG_S $f27, a0, 13*SZREG + 3*SZFREG
>+	FREG_S $f28, a0, 13*SZREG + 4*SZFREG
>+	FREG_S $f29, a0, 13*SZREG + 5*SZFREG
>+	FREG_S $f30, a0, 13*SZREG + 6*SZFREG
>+	FREG_S $f31, a0, 13*SZREG + 7*SZFREG
>+#endif
>+
>+#if !IS_IN (libc) && IS_IN(rtld)
>+	li.w		v0, 0
>+	jirl		zero,ra,0
>+#else
>+	b		__sigjmp_save
>+#endif
>+END (__sigsetjmp)
>+
>+hidden_def (__sigsetjmp)
>+weak_alias (_setjmp, __GI__setjmp)
>diff --git a/sysdeps/loongarch/sotruss-lib.c b/sysdeps/loongarch/sotruss-lib.c
>new file mode 100644
>index 0000000000..5b15f4815a
>--- /dev/null
>+++ b/sysdeps/loongarch/sotruss-lib.c
>@@ -0,0 +1,50 @@
>+/* Override generic sotruss-lib.c to define actual functions for LoongArch.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#define HAVE_ARCH_PLTENTER
>+#define HAVE_ARCH_PLTEXIT
>+
>+#include <elf/sotruss-lib.c>
>+
>+ElfW (Addr)
>+la_loongarch_gnu_pltenter (ElfW (Sym) * sym __attribute__ ((unused)),
>+			   unsigned int ndx __attribute__ ((unused)),
>+			   uintptr_t *refcook, uintptr_t *defcook,
>+			   La_loongarch_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_loongarch_gnu_pltexit (ElfW (Sym) * sym, unsigned int ndx,
>+			  uintptr_t *refcook, uintptr_t *defcook,
>+			  const struct La_loongarch_regs *inregs,
>+			  struct La_loongarch_retval *outregs,
>+			  const char *symname)
>+{
>+  print_exit (refcook, defcook, symname, outregs->lrv_a0);
>+
>+  return 0;
>+}
>diff --git a/sysdeps/loongarch/start.S b/sysdeps/loongarch/start.S
>new file mode 100644
>index 0000000000..a9b32aa966
>--- /dev/null
>+++ b/sysdeps/loongarch/start.S
>@@ -0,0 +1,67 @@
>+/* Startup code compliant to the ELF LoongArch ABI.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#define __ASSEMBLY__ 1
>+#include <entry.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.  */
>+
>+/*
>+int
>+__libc_start_main (int (*main) (int, char **, char **),
>+		   int argc,
>+		   char **argv,
>+		   __typeof (main) init,
>+		   void (*fini) (void),
>+		   void (*rtld_fini) (void),
>+		   void *stack_end);
>+ */
>+
>+ENTRY (ENTRY_POINT)
>+
>+/* Terminate call stack by noting ra is undefined.  Use a dummy
>+   .cfi_label to force starting the FDE.  */
>+	.cfi_label .Ldummy
>+	cfi_undefined (1)
>+	or		a5, a0, zero /* rtld_fini */
>+
>+/* We must get symbol main through GOT table, since main may not be local.
>+   For instance: googletest defines main in dynamic library.  */
>+	la.got		a0, t0, main
>+	REG_L		a1, sp, 0
>+	ADDI		a2, sp, SZREG
>+
>+	/* Adjust $sp for 16-aligned */
>+	SRLI		sp, sp, 4
>+	SLLI		sp, sp, 4
>+
>+	move		a3, zero /* used to be init */
>+	move		a4, zero /* used to be fini */
>+	or		a6, sp, zero /* stack_end */
>+
>+	la.got		ra, t0, __libc_start_main
>+	jirl		ra, ra, 0
>+
>+	la.got		ra, t0, abort
>+	jirl		ra, ra, 0
>+END (ENTRY_POINT)
>+
>diff --git a/sysdeps/loongarch/sys/asm.h b/sysdeps/loongarch/sys/asm.h
>new file mode 100644
>index 0000000000..b41ee59694
>--- /dev/null
>+++ b/sysdeps/loongarch/sys/asm.h
>@@ -0,0 +1,59 @@
>+/* Miscellaneous macros.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#ifndef _SYS_ASM_H
>+#define _SYS_ASM_H
>+
>+#include <sys/regdef.h>
>+#include <sysdeps/generic/sysdep.h>
>+
>+/* Macros to handle different pointer/register sizes for 32/64-bit code.  */
>+#define SZREG 8
>+#define SZFREG 8
>+#define REG_L ld.d
>+#define REG_S st.d
>+#define SRLI srli.d
>+#define SLLI slli.d
>+#define ADDI addi.d
>+#define ADD  add.d
>+#define BSTRINS  bstrins.d
>+#define LI  li.d
>+#define FREG_L fld.d
>+#define FREG_S fst.d
>+
>+/* Declare leaf routine.  */
>+#define LEAF(symbol) \
>+  .text; \
>+  .globl symbol; \
>+  .align 3; \
>+  cfi_startproc; \
>+  .type symbol, @function; \
>+  symbol:
>+
>+#define ENTRY(symbol) LEAF (symbol)
>+
>+/* 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/loongarch/tst-audit.h b/sysdeps/loongarch/tst-audit.h
>new file mode 100644
>index 0000000000..e71948c86e
>--- /dev/null
>+++ b/sysdeps/loongarch/tst-audit.h
>@@ -0,0 +1,23 @@
>+/* Definitions for testing PLT entry/exit auditing.
>+   Copyright (C) 2022 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
>+   <https://www.gnu.org/licenses/>.  */
>+
>+#define pltenter la_loongarch_gnu_pltenter
>+#define pltexit la_loongarch_gnu_pltexit
>+#define La_regs La_loongarch_regs
>+#define La_retval La_loongarch_retval
>+#define int_retval lrv_a0
>diff --git a/sysdeps/unix/sysv/linux/loongarch/ldconfig.h b/sysdeps/unix/sysv/linux/loongarch/ldconfig.h
>new file mode 100644
>index 0000000000..4887c30ca2
>--- /dev/null
>+++ b/sysdeps/unix/sysv/linux/loongarch/ldconfig.h
>@@ -0,0 +1,26 @@
>+/* ldconfig default paths and libraries.
>+   Copyright (C) 2022 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 <sysdeps/generic/ldconfig.h>
>+
>+#define SYSDEP_KNOWN_INTERPRETER_NAMES \
>+  { "/lib64/ld-linux-loongarch-lp64d.so.1", FLAG_ELF_LIBC6 },
>+
>+#define SYSDEP_KNOWN_LIBRARY_NAMES	\
>+  { "libc.so.6", FLAG_ELF_LIBC6 },	\
>+  { "libm.so.6", FLAG_ELF_LIBC6 },
>-- 
>2.31.1
>