nios2: Remove all GDB support for Nios II targets.

Intel has EOL'ed the Nios II architecture, and it's time to remove support
from all toolchain components before it gets any more bit-rotten from
lack of maintenance or regular testing.

24 files changed, 6 insertions, 3326 deletions

diff --git a/gdb/MAINTAINERS b/gdb/MAINTAINERS
index 128adff..927be43 100644
--- a/gdb/MAINTAINERS
+++ b/gdb/MAINTAINERS
@@ -383,9 +383,7 @@ the native maintainer when resolving ABI issues.
 
 	ms1		Deleted
 
-	nios2		--target=nios2-elf
-			--target=nios2-linux-gnu
-			Yao Qi			qiyao@sourceware.org
+	nios2		Deleted
 
 	ns32k		Deleted
 
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 93a789c..5295075 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -857,8 +857,6 @@ ALL_TARGET_OBS = \
 	msp430-tdep.o \
 	netbsd-tdep.o \
 	nds32-tdep.o \
-	nios2-linux-tdep.o \
-	nios2-tdep.o \
 	obsd-tdep.o \
 	or1k-linux-tdep.o \
 	or1k-tdep.o \
@@ -1441,7 +1439,6 @@ HFILES_NO_SRCDIR = \
 	netbsd-nat.h \
 	netbsd-tdep.h \
 	nds32-tdep.h \
-	nios2-tdep.h \
 	elf-none-tdep.h \
 	objc-lang.h \
 	objfiles.h \
@@ -1806,8 +1803,6 @@ ALLDEPFILES = \
 	netbsd-nat.c \
 	netbsd-tdep.c \
 	nds32-tdep.c \
-	nios2-linux-tdep.c \
-	nios2-tdep.c \
 	obsd-nat.c \
 	obsd-tdep.c \
 	or1k-linux-nat.c \
diff --git a/gdb/NEWS b/gdb/NEWS
index 0f2d9be..361d772 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,9 @@
 
 *** Changes since GDB 15
 
+* Support for Nios II targets has been removed as this architecture
+  has been EOL'ed by Intel.
+
 * GDB now supports watchpoints for tagged data pointers (see
   https://en.wikipedia.org/wiki/Tagged_pointer) on amd64, such as the
   one used by the Linear Address Masking (LAM) feature provided by
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 2d78c11..f7b9e32 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -466,17 +466,6 @@ nds32*-*-elf)
 	gdb_target_obs="nds32-tdep.o"
 	;;
 
-nios2*-*-linux*)
-	# Target: Altera Nios II running Linux
-	gdb_target_obs="nios2-tdep.o nios2-linux-tdep.o solib-svr4.o \
-			symfile-mem.o glibc-tdep.o linux-tdep.o"
-	;;
-
-nios2*-*-*)
-	# Target: Altera Nios II bare-metal
-	gdb_target_obs="nios2-tdep.o"
-	;;
-
 or1k*-*-linux*)
 	# Target: OpenCores OpenRISC 1000 32-bit running Linux
 	gdb_target_obs="or1k-tdep.o or1k-linux-tdep.o solib-svr4.o \
diff --git a/gdb/disasm-selftests.c b/gdb/disasm-selftests.c
index dd849fb..221b94f 100644
--- a/gdb/disasm-selftests.c
+++ b/gdb/disasm-selftests.c
@@ -92,10 +92,9 @@ get_test_insn (struct gdbarch *gdbarch, size_t *len)
       insn = xstormy16_insn;
       *len = sizeof (xstormy16_insn);
       break;
-    case bfd_arch_nios2:
     case bfd_arch_score:
     case bfd_arch_riscv:
-      /* nios2, riscv, and score need to know the current instruction
+      /* riscv and score need to know the current instruction
 	 to select breakpoint instruction.  Give the breakpoint
 	 instruction kind explicitly.  */
       {
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 7c6059d..85ac3d9 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -26426,7 +26426,6 @@ all uses of @value{GDBN} with the architecture, both native and cross.
 * MIPS::
 * HPPA::               HP PA architecture
 * PowerPC::
-* Nios II::
 * Sparc64::
 * S12Z::
 * AMD GPU::            @acronym{AMD GPU} architectures
@@ -27015,25 +27014,6 @@ by joining the even/odd register pairs @code{f0} and @code{f1} for @code{$dl0},
 For POWER7 processors, @value{GDBN} provides a set of pseudo-registers, the 64-bit
 wide Extended Floating Point Registers (@samp{f32} through @samp{f63}).
 
-@node Nios II
-@subsection Nios II
-@cindex Nios II architecture
-
-When @value{GDBN} is debugging the Nios II architecture,
-it provides the following special commands:
-
-@table @code
-
-@item set debug nios2
-@kindex set debug nios2
-This command turns on and off debugging messages for the Nios II
-target code in @value{GDBN}.
-
-@item show debug nios2
-@kindex show debug nios2
-Show the current setting of Nios II debugging messages.
-@end table
-
 @node Sparc64
 @subsection Sparc64
 @cindex Sparc64 support
@@ -49008,7 +48988,6 @@ registers using the capitalization used in the description.
 * MIPS Features::
 * M68K Features::
 * NDS32 Features::
-* Nios II Features::
 * OpenRISC 1000 Features::
 * PowerPC Features::
 * RISC-V Features::
@@ -49841,16 +49820,6 @@ overlapping 64-bit double-precision registers.  Listing 32-bit
 single-precision registers explicitly is deprecated, and the
 support to it could be totally removed some day.
 
-@node Nios II Features
-@subsection Nios II Features
-@cindex target descriptions, Nios II features
-
-The @samp{org.gnu.gdb.nios2.cpu} feature is required for Nios II
-targets.  It should contain the 32 core registers (@samp{zero},
-@samp{at}, @samp{r2} through @samp{r23}, @samp{et} through @samp{ra}),
-@samp{pc}, and the 16 control registers (@samp{status} through
-@samp{mpuacc}).
-
 @node OpenRISC 1000 Features
 @subsection Openrisc 1000 Features
 @cindex target descriptions, OpenRISC 1000 features
diff --git a/gdb/features/Makefile b/gdb/features/Makefile
index 4f42d00..7c10f20 100644
--- a/gdb/features/Makefile
+++ b/gdb/features/Makefile
@@ -46,7 +46,6 @@
 # List of .dat files to create in ../regformats/
 WHICH = mips-linux mips-dsp-linux \
 	mips64-linux mips64-dsp-linux \
-	nios2-linux \
 	or1k-linux \
 	rs6000/powerpc-32 \
 	rs6000/powerpc-32l rs6000/powerpc-altivec32l rs6000/powerpc-e500l \
@@ -73,7 +72,6 @@ mips-expedite = r29,pc
 mips-dsp-expedite = r29,pc
 mips64-expedite = r29,pc
 mips64-dsp-expedite = r29,pc
-nios2-linux-expedite = sp,pc
 or1k-expedite = r1,npc
 powerpc-expedite = r1,pc
 s390-linux32-expedite = r14,r15,pswa
@@ -107,7 +105,6 @@ XMLTOC = \
 	mips64-dsp-linux.xml \
 	mips64-linux.xml \
 	nds32.xml \
-	nios2.xml \
 	or1k.xml \
 	or1k-linux.xml \
 	rs6000/powerpc-32.xml \
diff --git a/gdb/features/nios2-cpu.xml b/gdb/features/nios2-cpu.xml
deleted file mode 100644
index 9e442df..0000000
--- a/gdb/features/nios2-cpu.xml
+++ /dev/null
@@ -1,59 +0,0 @@
-<?xml version="1.0"?>
-<!-- Copyright (C) 2012-2024 Free Software Foundation, Inc.
-
-     Copying and distribution of this file, with or without modification,
-     are permitted in any medium without royalty provided the copyright
-     notice and this notice are preserved.  -->
-
-<!DOCTYPE feature SYSTEM "gdb-target.dtd">
-<feature name="org.gnu.gdb.nios2.cpu">
-  <reg name="zero" bitsize="32" type="uint32"/>
-  <reg name="at" bitsize="32" type="uint32"/>
-  <reg name="r2" bitsize="32" type="uint32"/>
-  <reg name="r3" bitsize="32" type="uint32"/>
-  <reg name="r4" bitsize="32" type="uint32"/>
-  <reg name="r5" bitsize="32" type="uint32"/>
-  <reg name="r6" bitsize="32" type="uint32"/>
-  <reg name="r7" bitsize="32" type="uint32"/>
-  <reg name="r8" bitsize="32" type="uint32"/>
-  <reg name="r9" bitsize="32" type="uint32"/>
-  <reg name="r10" bitsize="32" type="uint32"/>
-  <reg name="r11" bitsize="32" type="uint32"/>
-  <reg name="r12" bitsize="32" type="uint32"/>
-  <reg name="r13" bitsize="32" type="uint32"/>
-  <reg name="r14" bitsize="32" type="uint32"/>
-  <reg name="r15" bitsize="32" type="uint32"/>
-  <reg name="r16" bitsize="32" type="uint32"/>
-  <reg name="r17" bitsize="32" type="uint32"/>
-  <reg name="r18" bitsize="32" type="uint32"/>
-  <reg name="r19" bitsize="32" type="uint32"/>
-  <reg name="r20" bitsize="32" type="uint32"/>
-  <reg name="r21" bitsize="32" type="uint32"/>
-  <reg name="r22" bitsize="32" type="uint32"/>
-  <reg name="r23" bitsize="32" type="uint32"/>
-  <reg name="et" bitsize="32" type="uint32"/>
-  <reg name="bt" bitsize="32" type="uint32"/>
-  <reg name="gp" bitsize="32" type="data_ptr"/>
-  <reg name="sp" bitsize="32" type="data_ptr"/>
-  <reg name="fp" bitsize="32" type="data_ptr"/>
-  <reg name="ea" bitsize="32" type="code_ptr"/>
-  <reg name="sstatus" bitsize="32" type="uint32"/>
-  <reg name="ra" bitsize="32" type="code_ptr"/>
-  <reg name="pc" bitsize="32" type="code_ptr"/>
-  <reg name="status" bitsize="32" type="uint32"/>
-  <reg name="estatus" bitsize="32" type="uint32"/>
-  <reg name="bstatus" bitsize="32" type="uint32"/>
-  <reg name="ienable" bitsize="32" type="uint32"/>
-  <reg name="ipending" bitsize="32" type="uint32"/>
-  <reg name="cpuid" bitsize="32" type="uint32"/>
-  <reg name="ctl6" bitsize="32" type="uint32"/>
-  <reg name="exception" bitsize="32" type="uint32"/>
-  <reg name="pteaddr" bitsize="32" type="uint32"/>
-  <reg name="tlbacc" bitsize="32" type="uint32"/>
-  <reg name="tlbmisc" bitsize="32" type="uint32"/>
-  <reg name="eccinj" bitsize="32" type="uint32"/>
-  <reg name="badaddr" bitsize="32" type="uint32"/>
-  <reg name="config" bitsize="32" type="uint32"/>
-  <reg name="mpubase" bitsize="32" type="uint32"/>
-  <reg name="mpuacc" bitsize="32" type="uint32"/>
-</feature>
diff --git a/gdb/features/nios2-linux.xml b/gdb/features/nios2-linux.xml
deleted file mode 100644
index 1c9f8c1..0000000
--- a/gdb/features/nios2-linux.xml
+++ /dev/null
@@ -1,13 +0,0 @@
-<?xml version="1.0"?>
-<!-- Copyright (C) 2012-2024 Free Software Foundation, Inc.
-
-     Copying and distribution of this file, with or without modification,
-     are permitted in any medium without royalty provided the copyright
-     notice and this notice are preserved.  -->
-
-<!DOCTYPE target SYSTEM "gdb-target.dtd">
-<target>
-  <architecture>nios2</architecture>
-  <osabi>GNU/Linux</osabi>
-  <xi:include href="nios2-cpu.xml"/>
-</target>
diff --git a/gdb/features/nios2.c b/gdb/features/nios2.c
deleted file mode 100644
index f53b0dd..0000000
--- a/gdb/features/nios2.c
+++ /dev/null
@@ -1,68 +0,0 @@
-/* THIS FILE IS GENERATED.  -*- buffer-read-only: t -*- vi:set ro:
-  Original: nios2.xml */
-
-#include "osabi.h"
-#include "target-descriptions.h"
-
-const struct target_desc *tdesc_nios2;
-static void
-initialize_tdesc_nios2 (void)
-{
-  target_desc_up result = allocate_target_description ();
-  set_tdesc_architecture (result.get (), bfd_scan_arch ("nios2"));
-
-  struct tdesc_feature *feature;
-
-  feature = tdesc_create_feature (result.get (), "org.gnu.gdb.nios2.cpu");
-  tdesc_create_reg (feature, "zero", 0, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "at", 1, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r2", 2, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r3", 3, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r4", 4, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r5", 5, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r6", 6, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r7", 7, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r8", 8, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r9", 9, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r10", 10, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r11", 11, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r12", 12, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r13", 13, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r14", 14, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r15", 15, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r16", 16, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r17", 17, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r18", 18, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r19", 19, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r20", 20, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r21", 21, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r22", 22, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "r23", 23, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "et", 24, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "bt", 25, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "gp", 26, 1, NULL, 32, "data_ptr");
-  tdesc_create_reg (feature, "sp", 27, 1, NULL, 32, "data_ptr");
-  tdesc_create_reg (feature, "fp", 28, 1, NULL, 32, "data_ptr");
-  tdesc_create_reg (feature, "ea", 29, 1, NULL, 32, "code_ptr");
-  tdesc_create_reg (feature, "sstatus", 30, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "ra", 31, 1, NULL, 32, "code_ptr");
-  tdesc_create_reg (feature, "pc", 32, 1, NULL, 32, "code_ptr");
-  tdesc_create_reg (feature, "status", 33, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "estatus", 34, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "bstatus", 35, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "ienable", 36, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "ipending", 37, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "cpuid", 38, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "ctl6", 39, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "exception", 40, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "pteaddr", 41, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "tlbacc", 42, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "tlbmisc", 43, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "eccinj", 44, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "badaddr", 45, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "config", 46, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "mpubase", 47, 1, NULL, 32, "uint32");
-  tdesc_create_reg (feature, "mpuacc", 48, 1, NULL, 32, "uint32");
-
-  tdesc_nios2 = result.release ();
-}
diff --git a/gdb/features/nios2.xml b/gdb/features/nios2.xml
deleted file mode 100644
index 6d8e043..0000000
--- a/gdb/features/nios2.xml
+++ /dev/null
@@ -1,12 +0,0 @@
-<?xml version="1.0"?>
-<!-- Copyright (C) 2013-2024 Free Software Foundation, Inc.
-
-     Copying and distribution of this file, with or without modification,
-     are permitted in any medium without royalty provided the copyright
-     notice and this notice are preserved.  -->
-
-<!DOCTYPE target SYSTEM "gdb-target.dtd">
-<target>
-  <architecture>nios2</architecture>
-  <xi:include href="nios2-cpu.xml"/>
-</target>
diff --git a/gdb/nios2-linux-tdep.c b/gdb/nios2-linux-tdep.c
deleted file mode 100644
index 085e13c..0000000
--- a/gdb/nios2-linux-tdep.c
+++ /dev/null
@@ -1,261 +0,0 @@
-/* Target-dependent code for GNU/Linux on Nios II.
-   Copyright (C) 2012-2024 Free Software Foundation, Inc.
-   Contributed by Mentor Graphics, Inc.
-
-   This file is part of GDB.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program 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 a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include "frame.h"
-#include "osabi.h"
-#include "solib-svr4.h"
-#include "trad-frame.h"
-#include "tramp-frame.h"
-#include "symtab.h"
-#include "regset.h"
-#include "regcache.h"
-#include "linux-tdep.h"
-#include "glibc-tdep.h"
-#include "nios2-tdep.h"
-#include "gdbarch.h"
-
-/* Core file and register set support.  */
-
-/* Map from the normal register enumeration order to the order that
-   registers appear in core files, which corresponds to the order
-   of the register slots in the kernel's struct pt_regs.  */
-
-static const int reg_offsets[NIOS2_NUM_REGS] =
-{
-  -1,  8,  9, 10, 11, 12, 13, 14,	/* r0 - r7 */
-  0,  1,  2,  3,  4,  5,  6,  7,	/* r8 - r15 */
-  23, 24, 25, 26, 27, 28, 29, 30,	/* r16 - r23 */
-  -1, -1, 19, 18, 17, 21, -1, 16,	/* et bt gp sp fp ea sstatus ra */
-  21,					/* pc */
-  -1, 20, -1, -1, -1, -1, -1, -1,	/* status estatus ...  */
-  -1, -1, -1, -1, -1, -1, -1, -1
-};
-
-/* General register set size.  Should match sizeof (struct pt_regs) +
-   sizeof (struct switch_stack) from the NIOS2 Linux kernel patch.  */
-
-#define NIOS2_GREGS_SIZE (4 * 34)
-
-/* Implement the supply_regset hook for core files.  */
-
-static void
-nios2_supply_gregset (const struct regset *regset,
-		      struct regcache *regcache,
-		      int regnum, const void *gregs_buf, size_t len)
-{
-  const gdb_byte *gregs = (const gdb_byte *) gregs_buf;
-  int regno;
-
-  for (regno = NIOS2_Z_REGNUM; regno <= NIOS2_MPUACC_REGNUM; regno++)
-    if (regnum == -1 || regnum == regno)
-      {
-	if (reg_offsets[regno] != -1)
-	  regcache->raw_supply (regno, gregs + 4 * reg_offsets[regno]);
-	else
-	  regcache->raw_supply_zeroed (regno);
-      }
-}
-
-/* Implement the collect_regset hook for core files.  */
-
-static void
-nios2_collect_gregset (const struct regset *regset,
-		       const struct regcache *regcache,
-		       int regnum, void *gregs_buf, size_t len)
-{
-  gdb_byte *gregs = (gdb_byte *) gregs_buf;
-  int regno;
-
-  for (regno = NIOS2_Z_REGNUM; regno <= NIOS2_MPUACC_REGNUM; regno++)
-    if (regnum == -1 || regnum == regno)
-      {
-	if (reg_offsets[regno] != -1)
-	  regcache->raw_collect (regno, gregs + 4 * reg_offsets[regno]);
-      }
-}
-
-static const struct regset nios2_core_regset =
-{
-  NULL,
-  nios2_supply_gregset,
-  nios2_collect_gregset
-};
-
-/* Iterate over core file register note sections.  */
-
-static void
-nios2_iterate_over_regset_sections (struct gdbarch *gdbarch,
-				    iterate_over_regset_sections_cb *cb,
-				    void *cb_data,
-				    const struct regcache *regcache)
-{
-  cb (".reg", NIOS2_GREGS_SIZE, NIOS2_GREGS_SIZE, &nios2_core_regset, NULL,
-      cb_data);
-}
-
-/* Initialize a trad-frame cache corresponding to the tramp-frame.
-   FUNC is the address of the instruction TRAMP[0] in memory.
-
-   This ABI is not documented.  It corresponds to rt_setup_ucontext in
-   the kernel arch/nios2/kernel/signal.c file.
-
-   The key points are:
-   - The kernel creates a trampoline at the hard-wired address 0x1044.
-   - The stack pointer points to an object of type struct rt_sigframe.
-     The definition of this structure is not exported from the kernel.
-     The register save area is located at offset 152 bytes (as determined
-     by inspection of the stack contents in the debugger), and the
-     registers are saved as r1-r23, ra, fp, gp, ea, sp.
-
-   This interface was implemented with kernel version 3.19 (the first
-   official mainline kernel).  Older unofficial kernel versions used
-   incompatible conventions; we do not support those here.  */
-
-#define NIOS2_SIGRETURN_TRAMP_ADDR 0x1044
-#define NIOS2_SIGRETURN_REGSAVE_OFFSET 152
-
-static void
-nios2_linux_rt_sigreturn_init (const struct tramp_frame *self,
-			       const frame_info_ptr &next_frame,
-			       struct trad_frame_cache *this_cache,
-			       CORE_ADDR func)
-{
-  CORE_ADDR sp = get_frame_register_unsigned (next_frame, NIOS2_SP_REGNUM);
-  CORE_ADDR base = sp + NIOS2_SIGRETURN_REGSAVE_OFFSET;
-  int i;
-
-  for (i = 0; i < 23; i++)
-    trad_frame_set_reg_addr (this_cache, i + 1, base + i * 4);
-  trad_frame_set_reg_addr (this_cache, NIOS2_RA_REGNUM, base + 23 * 4);
-  trad_frame_set_reg_addr (this_cache, NIOS2_FP_REGNUM, base + 24 * 4);
-  trad_frame_set_reg_addr (this_cache, NIOS2_GP_REGNUM, base + 25 * 4);
-  trad_frame_set_reg_addr (this_cache, NIOS2_PC_REGNUM, base + 27 * 4);
-  trad_frame_set_reg_addr (this_cache, NIOS2_SP_REGNUM, base + 28 * 4);
-
-  /* Save a frame ID.  */
-  trad_frame_set_id (this_cache, frame_id_build (base, func));
-}
-
-/* Trampoline for sigreturn.  This has the form
-     movi r2, __NR_rt_sigreturn
-     trap 0
-   appropriately encoded for R1 or R2.  */
-
-static struct tramp_frame nios2_r1_linux_rt_sigreturn_tramp_frame =
-{
-  SIGTRAMP_FRAME,
-  4,
-  {
-    { MATCH_R1_MOVI | SET_IW_I_B (2) | SET_IW_I_IMM16 (139), ULONGEST_MAX },
-    { MATCH_R1_TRAP | SET_IW_R_IMM5 (0), ULONGEST_MAX},
-    { TRAMP_SENTINEL_INSN }
-  },
-  nios2_linux_rt_sigreturn_init
-};
-
-static struct tramp_frame nios2_r2_linux_rt_sigreturn_tramp_frame =
-{
-  SIGTRAMP_FRAME,
-  4,
-  {
-    { MATCH_R2_MOVI | SET_IW_F2I16_B (2) | SET_IW_F2I16_IMM16 (139), ULONGEST_MAX },
-    { MATCH_R2_TRAP | SET_IW_X2L5_IMM5 (0), ULONGEST_MAX},
-    { TRAMP_SENTINEL_INSN }
-  },
-  nios2_linux_rt_sigreturn_init
-};
-
-/* When FRAME is at a syscall instruction, return the PC of the next
-   instruction to be executed.  */
-
-static CORE_ADDR
-nios2_linux_syscall_next_pc (const frame_info_ptr &frame,
-			     const struct nios2_opcode *op)
-{
-  CORE_ADDR pc = get_frame_pc (frame);
-  ULONGEST syscall_nr = get_frame_register_unsigned (frame, NIOS2_R2_REGNUM);
-
-  /* If we are about to make a sigreturn syscall, use the unwinder to
-     decode the signal frame.  */
-  if (syscall_nr == 139 /* rt_sigreturn */)
-    return frame_unwind_caller_pc (frame);
-
-  return pc + op->size;
-}
-
-/* Return true if PC is a kernel helper, a function mapped by the kernel
-   into user space on an unwritable page.  Currently the only such function
-   is __kuser_cmpxchg at 0x1004.  See arch/nios2/kernel/entry.S in the Linux
-   kernel sources and sysdeps/unix/sysv/linux/nios2/atomic-machine.h in
-   GLIBC.  */
-static bool
-nios2_linux_is_kernel_helper (CORE_ADDR pc)
-{
-  return pc == 0x1004;
-}
-
-/* Hook function for gdbarch_register_osabi.  */
-
-static void
-nios2_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
-{
-  nios2_gdbarch_tdep *tdep = gdbarch_tdep<nios2_gdbarch_tdep> (gdbarch);
-
-  linux_init_abi (info, gdbarch, 0);
-
-  /* Shared library handling.  */
-  set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
-  set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
-
-  set_solib_svr4_fetch_link_map_offsets (gdbarch,
-					 linux_ilp32_fetch_link_map_offsets);
-  /* Enable TLS support.  */
-  set_gdbarch_fetch_tls_load_module_address (gdbarch,
-					     svr4_fetch_objfile_link_map);
-  /* Core file support.  */
-  set_gdbarch_iterate_over_regset_sections
-    (gdbarch, nios2_iterate_over_regset_sections);
-  /* Linux signal frame unwinders.  */
-  if (gdbarch_bfd_arch_info (gdbarch)->mach == bfd_mach_nios2r2)
-    tramp_frame_prepend_unwinder (gdbarch,
-				  &nios2_r2_linux_rt_sigreturn_tramp_frame);
-  else
-    tramp_frame_prepend_unwinder (gdbarch,
-				  &nios2_r1_linux_rt_sigreturn_tramp_frame);
-
-  tdep->syscall_next_pc = nios2_linux_syscall_next_pc;
-  tdep->is_kernel_helper = nios2_linux_is_kernel_helper;
-
-  /* Index of target address word in glibc jmp_buf.  */
-  tdep->jb_pc = 10;
-}
-
-void _initialize_nios2_linux_tdep ();
-void
-_initialize_nios2_linux_tdep ()
-{
-
-  const struct bfd_arch_info *arch_info;
-
-  for (arch_info = bfd_lookup_arch (bfd_arch_nios2, 0);
-       arch_info != NULL;
-       arch_info = arch_info->next)
-    gdbarch_register_osabi (bfd_arch_nios2, arch_info->mach,
-			    GDB_OSABI_LINUX, nios2_linux_init_abi);
-}
diff --git a/gdb/nios2-tdep.c b/gdb/nios2-tdep.c
deleted file mode 100644
index 130c015..0000000
--- a/gdb/nios2-tdep.c
+++ /dev/null
@@ -1,2406 +0,0 @@
-/* Target-machine dependent code for Nios II, for GDB.
-   Copyright (C) 2012-2024 Free Software Foundation, Inc.
-   Contributed by Peter Brookes (pbrookes@altera.com)
-   and Andrew Draper (adraper@altera.com).
-   Contributed by Mentor Graphics, Inc.
-
-   This file is part of GDB.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program 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 a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include "extract-store-integer.h"
-#include "frame.h"
-#include "frame-unwind.h"
-#include "frame-base.h"
-#include "trad-frame.h"
-#include "dwarf2/frame.h"
-#include "symtab.h"
-#include "inferior.h"
-#include "gdbtypes.h"
-#include "gdbcore.h"
-#include "cli/cli-cmds.h"
-#include "osabi.h"
-#include "target.h"
-#include "dis-asm.h"
-#include "regcache.h"
-#include "value.h"
-#include "symfile.h"
-#include "arch-utils.h"
-#include "infcall.h"
-#include "regset.h"
-#include "target-descriptions.h"
-
-/* To get entry_point_address.  */
-#include "objfiles.h"
-#include <algorithm>
-
-/* Nios II specific header.  */
-#include "nios2-tdep.h"
-
-#include "features/nios2.c"
-
-/* Control debugging information emitted in this file.  */
-
-static bool nios2_debug = false;
-
-/* The following structures are used in the cache for prologue
-   analysis; see the reg_value and reg_saved tables in
-   struct nios2_unwind_cache, respectively.  */
-
-/* struct reg_value is used to record that a register has reg's initial
-   value at the start of a function plus the given constant offset.
-   If reg == 0, then the value is just the offset.
-   If reg < 0, then the value is unknown.  */
-
-struct reg_value
-{
-  int reg;
-  int offset;
-};
-
-/* struct reg_saved is used to record that a register value has been saved at
-   basereg + addr, for basereg >= 0.  If basereg < 0, that indicates
-   that the register is not known to have been saved.  Note that when
-   basereg == NIOS2_Z_REGNUM (that is, r0, which holds value 0),
-   addr is an absolute address.  */
-
-struct reg_saved
-{
-  int basereg;
-  CORE_ADDR addr;
-};
-
-struct nios2_unwind_cache
-{
-  /* The frame's base, optionally used by the high-level debug info.  */
-  CORE_ADDR base;
-
-  /* The previous frame's inner most stack address.  Used as this
-     frame ID's stack_addr.  */
-  CORE_ADDR cfa;
-
-  /* The address of the first instruction in this function.  */
-  CORE_ADDR pc;
-
-  /* Which register holds the return address for the frame.  */
-  int return_regnum;
-
-  /* Table indicating what changes have been made to each register.  */
-  struct reg_value reg_value[NIOS2_NUM_REGS];
-
-  /* Table indicating where each register has been saved.  */
-  struct reg_saved reg_saved[NIOS2_NUM_REGS];
-};
-
-
-/* This array is a mapping from Dwarf-2 register numbering to GDB's.  */
-
-static int nios2_dwarf2gdb_regno_map[] =
-{
-  0, 1, 2, 3,
-  4, 5, 6, 7,
-  8, 9, 10, 11,
-  12, 13, 14, 15,
-  16, 17, 18, 19,
-  20, 21, 22, 23,
-  24, 25,
-  NIOS2_GP_REGNUM,        /* 26 */
-  NIOS2_SP_REGNUM,        /* 27 */
-  NIOS2_FP_REGNUM,        /* 28 */
-  NIOS2_EA_REGNUM,        /* 29 */
-  NIOS2_BA_REGNUM,        /* 30 */
-  NIOS2_RA_REGNUM,        /* 31 */
-  NIOS2_PC_REGNUM,        /* 32 */
-  NIOS2_STATUS_REGNUM,    /* 33 */
-  NIOS2_ESTATUS_REGNUM,   /* 34 */
-  NIOS2_BSTATUS_REGNUM,   /* 35 */
-  NIOS2_IENABLE_REGNUM,   /* 36 */
-  NIOS2_IPENDING_REGNUM,  /* 37 */
-  NIOS2_CPUID_REGNUM,     /* 38 */
-  39, /* CTL6 */          /* 39 */
-  NIOS2_EXCEPTION_REGNUM, /* 40 */
-  NIOS2_PTEADDR_REGNUM,   /* 41 */
-  NIOS2_TLBACC_REGNUM,    /* 42 */
-  NIOS2_TLBMISC_REGNUM,   /* 43 */
-  NIOS2_ECCINJ_REGNUM,    /* 44 */
-  NIOS2_BADADDR_REGNUM,   /* 45 */
-  NIOS2_CONFIG_REGNUM,    /* 46 */
-  NIOS2_MPUBASE_REGNUM,   /* 47 */
-  NIOS2_MPUACC_REGNUM     /* 48 */
-};
-
-static_assert (ARRAY_SIZE (nios2_dwarf2gdb_regno_map) == NIOS2_NUM_REGS);
-
-/* Implement the dwarf2_reg_to_regnum gdbarch method.  */
-
-static int
-nios2_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int dw_reg)
-{
-  if (dw_reg < 0 || dw_reg >= NIOS2_NUM_REGS)
-    return -1;
-
-  return nios2_dwarf2gdb_regno_map[dw_reg];
-}
-
-/* Canonical names for the 49 registers.  */
-
-static const char *const nios2_reg_names[NIOS2_NUM_REGS] =
-{
-  "zero", "at", "r2", "r3", "r4", "r5", "r6", "r7",
-  "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
-  "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
-  "et", "bt", "gp", "sp", "fp", "ea", "sstatus", "ra",
-  "pc",
-  "status", "estatus", "bstatus", "ienable",
-  "ipending", "cpuid", "ctl6", "exception",
-  "pteaddr", "tlbacc", "tlbmisc", "eccinj",
-  "badaddr", "config", "mpubase", "mpuacc"
-};
-
-/* Implement the register_name gdbarch method.  */
-
-static const char *
-nios2_register_name (struct gdbarch *gdbarch, int regno)
-{
-  /* Use mnemonic aliases for GPRs.  */
-  if (regno < NIOS2_NUM_REGS)
-    return nios2_reg_names[regno];
-  else
-    return tdesc_register_name (gdbarch, regno);
-}
-
-/* Implement the register_type gdbarch method.  */
-
-static struct type *
-nios2_register_type (struct gdbarch *gdbarch, int regno)
-{
-  /* If the XML description has register information, use that to
-     determine the register type.  */
-  if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
-    return tdesc_register_type (gdbarch, regno);
-
-  if (regno == NIOS2_PC_REGNUM)
-    return builtin_type (gdbarch)->builtin_func_ptr;
-  else if (regno == NIOS2_SP_REGNUM)
-    return builtin_type (gdbarch)->builtin_data_ptr;
-  else
-    return builtin_type (gdbarch)->builtin_uint32;
-}
-
-/* Given a return value in REGCACHE with a type VALTYPE,
-   extract and copy its value into VALBUF.  */
-
-static void
-nios2_extract_return_value (struct gdbarch *gdbarch, struct type *valtype,
-			    struct regcache *regcache, gdb_byte *valbuf)
-{
-  int len = valtype->length ();
-
-  /* Return values of up to 8 bytes are returned in $r2 $r3.  */
-  if (len <= register_size (gdbarch, NIOS2_R2_REGNUM))
-    regcache->cooked_read (NIOS2_R2_REGNUM, valbuf);
-  else
-    {
-      gdb_assert (len <= (register_size (gdbarch, NIOS2_R2_REGNUM)
-			  + register_size (gdbarch, NIOS2_R3_REGNUM)));
-      regcache->cooked_read (NIOS2_R2_REGNUM, valbuf);
-      regcache->cooked_read (NIOS2_R3_REGNUM, valbuf + 4);
-    }
-}
-
-/* Write into appropriate registers a function return value
-   of type TYPE, given in virtual format.  */
-
-static void
-nios2_store_return_value (struct gdbarch *gdbarch, struct type *valtype,
-			  struct regcache *regcache, const gdb_byte *valbuf)
-{
-  int len = valtype->length ();
-
-  /* Return values of up to 8 bytes are returned in $r2 $r3.  */
-  if (len <= register_size (gdbarch, NIOS2_R2_REGNUM))
-    regcache->cooked_write (NIOS2_R2_REGNUM, valbuf);
-  else
-    {
-      gdb_assert (len <= (register_size (gdbarch, NIOS2_R2_REGNUM)
-			  + register_size (gdbarch, NIOS2_R3_REGNUM)));
-      regcache->cooked_write (NIOS2_R2_REGNUM, valbuf);
-      regcache->cooked_write (NIOS2_R3_REGNUM, valbuf + 4);
-    }
-}
-
-
-/* Set up the default values of the registers.  */
-
-static void
-nios2_setup_default (struct nios2_unwind_cache *cache)
-{
-  int i;
-
-  for (i = 0; i < NIOS2_NUM_REGS; i++)
-    {
-      /* All registers start off holding their previous values.  */
-      cache->reg_value[i].reg    = i;
-      cache->reg_value[i].offset = 0;
-
-      /* All registers start off not saved.  */
-      cache->reg_saved[i].basereg = -1;
-      cache->reg_saved[i].addr    = 0;
-    }
-}
-
-/* Initialize the unwind cache.  */
-
-static void
-nios2_init_cache (struct nios2_unwind_cache *cache, CORE_ADDR pc)
-{
-  cache->base = 0;
-  cache->cfa = 0;
-  cache->pc = pc;
-  cache->return_regnum = NIOS2_RA_REGNUM;
-  nios2_setup_default (cache);
-}
-
-/* Read and identify an instruction at PC.  If INSNP is non-null,
-   store the instruction word into that location.  Return the opcode
-   pointer or NULL if the memory couldn't be read or disassembled.  */
-
-static const struct nios2_opcode *
-nios2_fetch_insn (struct gdbarch *gdbarch, CORE_ADDR pc,
-		  unsigned int *insnp)
-{
-  LONGEST memword;
-  unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach;
-  unsigned int insn;
-
-  if (mach == bfd_mach_nios2r2)
-    {
-      if (!safe_read_memory_integer (pc, NIOS2_OPCODE_SIZE,
-				     BFD_ENDIAN_LITTLE, &memword)
-	  && !safe_read_memory_integer (pc, NIOS2_CDX_OPCODE_SIZE,
-					BFD_ENDIAN_LITTLE, &memword))
-	return NULL;
-    }
-  else if (!safe_read_memory_integer (pc, NIOS2_OPCODE_SIZE,
-				      gdbarch_byte_order (gdbarch), &memword))
-    return NULL;
-
-  insn = (unsigned int) memword;
-  if (insnp)
-    *insnp = insn;
-  return nios2_find_opcode_hash (insn, mach);
-}
-
-
-/* Match and disassemble an ADD-type instruction, with 3 register operands.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_add (uint32_t insn, const struct nios2_opcode *op,
-		 unsigned long mach, int *ra, int *rb, int *rc)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && (op->match == MATCH_R1_ADD || op->match == MATCH_R1_MOV))
-    {
-      *ra = GET_IW_R_A (insn);
-      *rb = GET_IW_R_B (insn);
-      *rc = GET_IW_R_C (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_ADD || op->match == MATCH_R2_MOV)
-    {
-      *ra = GET_IW_F3X6L5_A (insn);
-      *rb = GET_IW_F3X6L5_B (insn);
-      *rc = GET_IW_F3X6L5_C (insn);
-      return 1;
-    }
-  else if (op->match == MATCH_R2_ADD_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T3X1_A3 (insn)];
-      *rb = nios2_r2_reg3_mappings[GET_IW_T3X1_B3 (insn)];
-      *rc = nios2_r2_reg3_mappings[GET_IW_T3X1_C3 (insn)];
-      return 1;
-    }
-  else if (op->match == MATCH_R2_MOV_N)
-    {
-      *ra = GET_IW_F2_A (insn);
-      *rb = 0;
-      *rc = GET_IW_F2_B (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a SUB-type instruction, with 3 register operands.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_sub (uint32_t insn, const struct nios2_opcode *op,
-		 unsigned long mach, int *ra, int *rb, int *rc)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_SUB)
-    {
-      *ra = GET_IW_R_A (insn);
-      *rb = GET_IW_R_B (insn);
-      *rc = GET_IW_R_C (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_SUB)
-    {
-      *ra = GET_IW_F3X6L5_A (insn);
-      *rb = GET_IW_F3X6L5_B (insn);
-      *rc = GET_IW_F3X6L5_C (insn);
-      return 1;
-    }
-  else if (op->match == MATCH_R2_SUB_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T3X1_A3 (insn)];
-      *rb = nios2_r2_reg3_mappings[GET_IW_T3X1_B3 (insn)];
-      *rc = nios2_r2_reg3_mappings[GET_IW_T3X1_C3 (insn)];
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble an ADDI-type instruction, with 2 register operands
-   and one immediate operand.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_addi (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, int *ra, int *rb, int *imm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_ADDI)
-    {
-      *ra = GET_IW_I_A (insn);
-      *rb = GET_IW_I_B (insn);
-      *imm = (signed) (GET_IW_I_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_ADDI)
-    {
-      *ra = GET_IW_F2I16_A (insn);
-      *rb = GET_IW_F2I16_B (insn);
-      *imm = (signed) (GET_IW_F2I16_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_ADDI_N || op->match == MATCH_R2_SUBI_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T2X1I3_A3 (insn)];
-      *rb = nios2_r2_reg3_mappings[GET_IW_T2X1I3_B3 (insn)];
-      *imm = nios2_r2_asi_n_mappings[GET_IW_T2X1I3_IMM3 (insn)];
-      if (op->match == MATCH_R2_SUBI_N)
-	*imm = - (*imm);
-      return 1;
-    }
-  else if (op->match == MATCH_R2_SPADDI_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T1I7_A3 (insn)];
-      *rb = NIOS2_SP_REGNUM;
-      *imm = GET_IW_T1I7_IMM7 (insn) << 2;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_SPINCI_N || op->match == MATCH_R2_SPDECI_N)
-    {
-      *ra = NIOS2_SP_REGNUM;
-      *rb = NIOS2_SP_REGNUM;
-      *imm = GET_IW_X1I7_IMM7 (insn) << 2;
-      if (op->match == MATCH_R2_SPDECI_N)
-	*imm = - (*imm);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble an ORHI-type instruction, with 2 register operands
-   and one unsigned immediate operand.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_orhi (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, int *ra, int *rb, unsigned int *uimm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_ORHI)
-    {
-      *ra = GET_IW_I_A (insn);
-      *rb = GET_IW_I_B (insn);
-      *uimm = GET_IW_I_IMM16 (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_ORHI)
-    {
-      *ra = GET_IW_F2I16_A (insn);
-      *rb = GET_IW_F2I16_B (insn);
-      *uimm = GET_IW_F2I16_IMM16 (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a STW-type instruction, with 2 register operands
-   and one immediate operand.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_stw (uint32_t insn, const struct nios2_opcode *op,
-		 unsigned long mach, int *ra, int *rb, int *imm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && (op->match == MATCH_R1_STW || op->match == MATCH_R1_STWIO))
-    {
-      *ra = GET_IW_I_A (insn);
-      *rb = GET_IW_I_B (insn);
-      *imm = (signed) (GET_IW_I_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_STW)
-    {
-      *ra = GET_IW_F2I16_A (insn);
-      *rb = GET_IW_F2I16_B (insn);
-      *imm = (signed) (GET_IW_F2I16_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_STWIO)
-    {
-      *ra = GET_IW_F2X4I12_A (insn);
-      *rb = GET_IW_F2X4I12_B (insn);
-      *imm = (signed) (GET_IW_F2X4I12_IMM12 (insn) << 20) >> 20;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_STW_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T2I4_A3 (insn)];
-      *rb = nios2_r2_reg3_mappings[GET_IW_T2I4_B3 (insn)];
-      *imm = GET_IW_T2I4_IMM4 (insn) << 2;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_STWSP_N)
-    {
-      *ra = NIOS2_SP_REGNUM;
-      *rb = GET_IW_F1I5_B (insn);
-      *imm = GET_IW_F1I5_IMM5 (insn) << 2;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_STWZ_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T1X1I6_A3 (insn)];
-      *rb = 0;
-      *imm = GET_IW_T1X1I6_IMM6 (insn) << 2;
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a LDW-type instruction, with 2 register operands
-   and one immediate operand.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_ldw (uint32_t insn, const struct nios2_opcode *op,
-		 unsigned long mach, int *ra, int *rb, int *imm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && (op->match == MATCH_R1_LDW || op->match == MATCH_R1_LDWIO))
-    {
-      *ra = GET_IW_I_A (insn);
-      *rb = GET_IW_I_B (insn);
-      *imm = (signed) (GET_IW_I_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_LDW)
-    {
-      *ra = GET_IW_F2I16_A (insn);
-      *rb = GET_IW_F2I16_B (insn);
-      *imm = (signed) (GET_IW_F2I16_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_LDWIO)
-    {
-      *ra = GET_IW_F2X4I12_A (insn);
-      *rb = GET_IW_F2X4I12_B (insn);
-      *imm = (signed) (GET_IW_F2X4I12_IMM12 (insn) << 20) >> 20;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_LDW_N)
-    {
-      *ra = nios2_r2_reg3_mappings[GET_IW_T2I4_A3 (insn)];
-      *rb = nios2_r2_reg3_mappings[GET_IW_T2I4_B3 (insn)];
-      *imm = GET_IW_T2I4_IMM4 (insn) << 2;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_LDWSP_N)
-    {
-      *ra = NIOS2_SP_REGNUM;
-      *rb = GET_IW_F1I5_B (insn);
-      *imm = GET_IW_F1I5_IMM5 (insn) << 2;
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a RDCTL instruction, with 2 register operands.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_rdctl (uint32_t insn, const struct nios2_opcode *op,
-		   unsigned long mach, int *ra, int *rc)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && (op->match == MATCH_R1_RDCTL))
-    {
-      *ra = GET_IW_R_IMM5 (insn);
-      *rc = GET_IW_R_C (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_RDCTL)
-    {
-      *ra = GET_IW_F3X6L5_IMM5 (insn);
-      *rc = GET_IW_F3X6L5_C (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a PUSH.N or STWM instruction.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_stwm (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, unsigned int *reglist,
-		  int *ra, int *imm, int *wb, int *id)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_PUSH_N)
-    {
-      *reglist = 1 << 31;
-      if (GET_IW_L5I4X1_FP (insn))
-	*reglist |= (1 << 28);
-      if (GET_IW_L5I4X1_CS (insn))
-	{
-	  int val = GET_IW_L5I4X1_REGRANGE (insn);
-	  *reglist |= nios2_r2_reg_range_mappings[val];
-	}
-      *ra = NIOS2_SP_REGNUM;
-      *imm = GET_IW_L5I4X1_IMM4 (insn) << 2;
-      *wb = 1;
-      *id = 0;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_STWM)
-    {
-      unsigned int rawmask = GET_IW_F1X4L17_REGMASK (insn);
-      if (GET_IW_F1X4L17_RS (insn))
-	{
-	  *reglist = ((rawmask << 14) & 0x00ffc000);
-	  if (rawmask & (1 << 10))
-	    *reglist |= (1 << 28);
-	  if (rawmask & (1 << 11))
-	    *reglist |= (1 << 31);
-	}
-      else
-	*reglist = rawmask << 2;
-      *ra = GET_IW_F1X4L17_A (insn);
-      *imm = 0;
-      *wb = GET_IW_F1X4L17_WB (insn);
-      *id = GET_IW_F1X4L17_ID (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a POP.N or LDWM instruction.
-   Returns true on success, and fills in the operand pointers.  */
-
-static int
-nios2_match_ldwm (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, unsigned int *reglist,
-		  int *ra, int *imm, int *wb, int *id, int *ret)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_POP_N)
-    {
-      *reglist = 1 << 31;
-      if (GET_IW_L5I4X1_FP (insn))
-	*reglist |= (1 << 28);
-      if (GET_IW_L5I4X1_CS (insn))
-	{
-	  int val = GET_IW_L5I4X1_REGRANGE (insn);
-	  *reglist |= nios2_r2_reg_range_mappings[val];
-	}
-      *ra = NIOS2_SP_REGNUM;
-      *imm = GET_IW_L5I4X1_IMM4 (insn) << 2;
-      *wb = 1;
-      *id = 1;
-      *ret = 1;
-      return 1;
-    }
-  else if (op->match == MATCH_R2_LDWM)
-    {
-      unsigned int rawmask = GET_IW_F1X4L17_REGMASK (insn);
-      if (GET_IW_F1X4L17_RS (insn))
-	{
-	  *reglist = ((rawmask << 14) & 0x00ffc000);
-	  if (rawmask & (1 << 10))
-	    *reglist |= (1 << 28);
-	  if (rawmask & (1 << 11))
-	    *reglist |= (1 << 31);
-	}
-      else
-	*reglist = rawmask << 2;
-      *ra = GET_IW_F1X4L17_A (insn);
-      *imm = 0;
-      *wb = GET_IW_F1X4L17_WB (insn);
-      *id = GET_IW_F1X4L17_ID (insn);
-      *ret = GET_IW_F1X4L17_PC (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a branch instruction, with (potentially)
-   2 register operands and one immediate operand.
-   Returns true on success, and fills in the operand pointers.  */
-
-enum branch_condition {
-  branch_none,
-  branch_eq,
-  branch_ne,
-  branch_ge,
-  branch_geu,
-  branch_lt,
-  branch_ltu
-};
-  
-static int
-nios2_match_branch (uint32_t insn, const struct nios2_opcode *op,
-		    unsigned long mach, int *ra, int *rb, int *imm,
-		    enum branch_condition *cond)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2)
-    {
-      switch (op->match)
-	{
-	case MATCH_R1_BR:
-	  *cond = branch_none;
-	  break;
-	case MATCH_R1_BEQ:
-	  *cond = branch_eq;
-	  break;
-	case MATCH_R1_BNE:
-	  *cond = branch_ne;
-	  break;
-	case MATCH_R1_BGE:
-	  *cond = branch_ge;
-	  break;
-	case MATCH_R1_BGEU:
-	  *cond = branch_geu;
-	  break;
-	case MATCH_R1_BLT:
-	  *cond = branch_lt;
-	  break;
-	case MATCH_R1_BLTU:
-	  *cond = branch_ltu;
-	  break;
-	default:
-	  return 0;
-	}
-      *imm = (signed) (GET_IW_I_IMM16 (insn) << 16) >> 16;
-      *ra = GET_IW_I_A (insn);
-      *rb = GET_IW_I_B (insn);
-      return 1;
-    }
-  else
-    {
-      switch (op->match)
-	{
-	case MATCH_R2_BR_N:
-	  *cond = branch_none;
-	  *ra = NIOS2_Z_REGNUM;
-	  *rb = NIOS2_Z_REGNUM;
-	  *imm = (signed) ((GET_IW_I10_IMM10 (insn) << 1) << 21) >> 21;
-	  return 1;
-	case MATCH_R2_BEQZ_N:
-	  *cond = branch_eq;
-	  *ra = nios2_r2_reg3_mappings[GET_IW_T1I7_A3 (insn)];
-	  *rb = NIOS2_Z_REGNUM;
-	  *imm = (signed) ((GET_IW_T1I7_IMM7 (insn) << 1) << 24) >> 24;
-	  return 1;
-	case MATCH_R2_BNEZ_N:
-	  *cond = branch_ne;
-	  *ra = nios2_r2_reg3_mappings[GET_IW_T1I7_A3 (insn)];
-	  *rb = NIOS2_Z_REGNUM;
-	  *imm = (signed) ((GET_IW_T1I7_IMM7 (insn) << 1) << 24) >> 24;
-	  return 1;
-	case MATCH_R2_BR:
-	  *cond = branch_none;
-	  break;
-	case MATCH_R2_BEQ:
-	  *cond = branch_eq;
-	  break;
-	case MATCH_R2_BNE:
-	  *cond = branch_ne;
-	  break;
-	case MATCH_R2_BGE:
-	  *cond = branch_ge;
-	  break;
-	case MATCH_R2_BGEU:
-	  *cond = branch_geu;
-	  break;
-	case MATCH_R2_BLT:
-	  *cond = branch_lt;
-	  break;
-	case MATCH_R2_BLTU:
-	  *cond = branch_ltu;
-	  break;
-	default:
-	  return 0;
-	}
-      *ra = GET_IW_F2I16_A (insn);
-      *rb = GET_IW_F2I16_B (insn);
-      *imm = (signed) (GET_IW_F2I16_IMM16 (insn) << 16) >> 16;
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a direct jump instruction, with an
-   unsigned operand.  Returns true on success, and fills in the operand
-   pointer.  */
-
-static int
-nios2_match_jmpi (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, unsigned int *uimm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_JMPI)
-    {
-      *uimm = GET_IW_J_IMM26 (insn) << 2;
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_JMPI)
-    {
-      *uimm = GET_IW_L26_IMM26 (insn) << 2;
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a direct call instruction, with an
-   unsigned operand.  Returns true on success, and fills in the operand
-   pointer.  */
-
-static int
-nios2_match_calli (uint32_t insn, const struct nios2_opcode *op,
-		   unsigned long mach, unsigned int *uimm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_CALL)
-    {
-      *uimm = GET_IW_J_IMM26 (insn) << 2;
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_CALL)
-    {
-      *uimm = GET_IW_L26_IMM26 (insn) << 2;
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble an indirect jump instruction, with a
-   (possibly implicit) register operand.  Returns true on success, and fills
-   in the operand pointer.  */
-
-static int
-nios2_match_jmpr (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, int *ra)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2)
-    switch (op->match)
-      {
-      case MATCH_R1_JMP:
-	*ra = GET_IW_I_A (insn);
-	return 1;
-      case MATCH_R1_RET:
-	*ra = NIOS2_RA_REGNUM;
-	return 1;
-      case MATCH_R1_ERET:
-	*ra = NIOS2_EA_REGNUM;
-	return 1;
-      case MATCH_R1_BRET:
-	*ra = NIOS2_BA_REGNUM;
-	return 1;
-      default:
-	return 0;
-      }
-  else
-    switch (op->match)
-      {
-      case MATCH_R2_JMP:
-	*ra = GET_IW_F2I16_A (insn);
-	return 1;
-      case MATCH_R2_JMPR_N:
-	*ra = GET_IW_F1X1_A (insn);
-	return 1;
-      case MATCH_R2_RET:
-      case MATCH_R2_RET_N:
-	*ra = NIOS2_RA_REGNUM;
-	return 1;
-      case MATCH_R2_ERET:
-	*ra = NIOS2_EA_REGNUM;
-	return 1;
-      case MATCH_R2_BRET:
-	*ra = NIOS2_BA_REGNUM;
-	return 1;
-      default:
-	return 0;
-      }
-  return 0;
-}
-
-/* Match and disassemble an indirect call instruction, with a register
-   operand.  Returns true on success, and fills in the operand pointer.  */
-
-static int
-nios2_match_callr (uint32_t insn, const struct nios2_opcode *op,
-		   unsigned long mach, int *ra)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_CALLR)
-    {
-      *ra = GET_IW_I_A (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_CALLR)
-    {
-      *ra = GET_IW_F2I16_A (insn);
-      return 1;
-    }
-  else if (op->match == MATCH_R2_CALLR_N)
-    {
-      *ra = GET_IW_F1X1_A (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a break instruction, with an unsigned operand.
-   Returns true on success, and fills in the operand pointer.  */
-
-static int
-nios2_match_break (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, unsigned int *uimm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_BREAK)
-    {
-      *uimm = GET_IW_R_IMM5 (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_BREAK)
-    {
-      *uimm = GET_IW_F3X6L5_IMM5 (insn);
-      return 1;
-    }
-  else if (op->match == MATCH_R2_BREAK_N)
-    {
-      *uimm = GET_IW_X2L5_IMM5 (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Match and disassemble a trap instruction, with an unsigned operand.
-   Returns true on success, and fills in the operand pointer.  */
-
-static int
-nios2_match_trap (uint32_t insn, const struct nios2_opcode *op,
-		  unsigned long mach, unsigned int *uimm)
-{
-  int is_r2 = (mach == bfd_mach_nios2r2);
-
-  if (!is_r2 && op->match == MATCH_R1_TRAP)
-    {
-      *uimm = GET_IW_R_IMM5 (insn);
-      return 1;
-    }
-  else if (!is_r2)
-    return 0;
-  else if (op->match == MATCH_R2_TRAP)
-    {
-      *uimm = GET_IW_F3X6L5_IMM5 (insn);
-      return 1;
-    }
-  else if (op->match == MATCH_R2_TRAP_N)
-    {
-      *uimm = GET_IW_X2L5_IMM5 (insn);
-      return 1;
-    }
-  return 0;
-}
-
-/* Helper function to identify when we're in a function epilogue;
-   that is, the part of the function from the point at which the
-   stack adjustments are made, to the return or sibcall.
-   Note that we may have several stack adjustment instructions, and
-   this function needs to test whether the stack teardown has already
-   started before current_pc, not whether it has completed.  */
-
-static int
-nios2_in_epilogue_p (struct gdbarch *gdbarch,
-		     CORE_ADDR current_pc,
-		     CORE_ADDR start_pc)
-{
-  unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach;
-  int is_r2 = (mach == bfd_mach_nios2r2);
-  /* Maximum number of possibly-epilogue instructions to check.
-     Note that this number should not be too large, else we can
-     potentially end up iterating through unmapped memory.  */
-  int ninsns, max_insns = 5;
-  unsigned int insn;
-  const struct nios2_opcode *op = NULL;
-  unsigned int uimm;
-  int imm;
-  int wb, id, ret;
-  int ra, rb, rc;
-  enum branch_condition cond;
-  CORE_ADDR pc;
-
-  /* There has to be a previous instruction in the function.  */
-  if (current_pc <= start_pc)
-    return 0;
-
-  /* Find the previous instruction before current_pc.  For R2, it might
-     be either a 16-bit or 32-bit instruction; the only way to know for
-     sure is to scan through from the beginning of the function,
-     disassembling as we go.  */
-  if (is_r2)
-    for (pc = start_pc; ; )
-      {
-	op = nios2_fetch_insn (gdbarch, pc, &insn);
-	if (op == NULL)
-	  return 0;
-	if (pc + op->size < current_pc)
-	  pc += op->size;
-	else
-	  break;
-	/* We can skip over insns to a forward branch target.  Since
-	   the branch offset is relative to the next instruction,
-	   it's correct to do this after incrementing the pc above.  */
-	if (nios2_match_branch (insn, op, mach, &ra, &rb, &imm, &cond)
-	    && imm > 0
-	    && pc + imm < current_pc)
-	  pc += imm;
-      }
-  /* Otherwise just go back to the previous 32-bit insn.  */
-  else
-    pc = current_pc - NIOS2_OPCODE_SIZE;
-
-  /* Beginning with the previous instruction we just located, check whether
-     we are in a sequence of at least one stack adjustment instruction.
-     Possible instructions here include:
-	 ADDI sp, sp, n
-	 ADD sp, sp, rn
-	 LDW sp, n(sp)
-	 SPINCI.N n
-	 LDWSP.N sp, n(sp)
-	 LDWM {reglist}, (sp)++, wb */
-  for (ninsns = 0; ninsns < max_insns; ninsns++)
-    {
-      int ok = 0;
-
-      /* Fetch the insn at pc.  */
-      op = nios2_fetch_insn (gdbarch, pc, &insn);
-      if (op == NULL)
-	return 0;
-      pc += op->size;
-
-      /* Was it a stack adjustment?  */
-      if (nios2_match_addi (insn, op, mach, &ra, &rb, &imm))
-	ok = (rb == NIOS2_SP_REGNUM);
-      else if (nios2_match_add (insn, op, mach, &ra, &rb, &rc))
-	ok = (rc == NIOS2_SP_REGNUM);
-      else if (nios2_match_ldw (insn, op, mach, &ra, &rb, &imm))
-	ok = (rb == NIOS2_SP_REGNUM);
-      else if (nios2_match_ldwm (insn, op, mach, &uimm, &ra,
-				 &imm, &wb, &ret, &id))
-	ok = (ra == NIOS2_SP_REGNUM && wb && id);
-      if (!ok)
-	break;
-    }
-
-  /* No stack adjustments found.  */
-  if (ninsns == 0)
-    return 0;
-
-  /* We found more stack adjustments than we expect GCC to be generating.
-     Since it looks like a stack unwind might be in progress tell GDB to
-     treat it as such.  */
-  if (ninsns == max_insns)
-    return 1;
-
-  /* The next instruction following the stack adjustments must be a
-     return, jump, or unconditional branch, or a CDX pop.n or ldwm
-     that does an implicit return.  */
-  if (nios2_match_jmpr (insn, op, mach, &ra)
-      || nios2_match_jmpi (insn, op, mach, &uimm)
-      || (nios2_match_ldwm (insn, op, mach, &uimm, &ra, &imm, &wb, &id, &ret)
-	  && ret)
-      || (nios2_match_branch (insn, op, mach, &ra, &rb, &imm, &cond)
-	  && cond == branch_none))
-    return 1;
-
-  return 0;
-}
-
-/* Implement the stack_frame_destroyed_p gdbarch method.  */
-
-static int
-nios2_stack_frame_destroyed_p (struct gdbarch *gdbarch, CORE_ADDR pc)
-{
-  CORE_ADDR func_addr;
-
-  if (find_pc_partial_function (pc, NULL, &func_addr, NULL))
-    return nios2_in_epilogue_p (gdbarch, pc, func_addr);
-
-  return 0;
-}
-
-/* Do prologue analysis, returning the PC of the first instruction
-   after the function prologue.  Assumes CACHE has already been
-   initialized.  THIS_FRAME can be null, in which case we are only
-   interested in skipping the prologue.  Otherwise CACHE is filled in
-   from the frame information.
-
-   The prologue may consist of the following parts:
-     1) Profiling instrumentation.  For non-PIC code it looks like:
-	  mov	 r8, ra
-	  call	 mcount
-	  mov	 ra, r8
-
-     2) A stack adjustment and save of R4-R7 for varargs functions.
-	For R2 CDX this is typically handled with a STWM, otherwise
-	this is typically merged with item 3.
-
-     3) A stack adjustment and save of the callee-saved registers.
-	For R2 CDX these are typically handled with a PUSH.N or STWM,
-	otherwise as an explicit SP decrement and individual register
-	saves.
-
-	There may also be a stack switch here in an exception handler
-	in place of a stack adjustment.  It looks like:
-	  movhi  rx, %hiadj(newstack)
-	  addhi  rx, rx, %lo(newstack)
-	  stw    sp, constant(rx)
-	  mov    sp, rx
-
-     4) A frame pointer save, which can be either a MOV or ADDI.
-
-     5) A further stack pointer adjustment.  This is normally included
-	adjustment in step 3 unless the total adjustment is too large
-	to be done in one step.
-
-     7) A stack overflow check, which can take either of these forms:
-	  bgeu   sp, rx, +8
-	  trap  3
-	or
-	  bltu   sp, rx, .Lstack_overflow
-	  ...
-	.Lstack_overflow:
-	  trap  3
-	  
-	Older versions of GCC emitted "break 3" instead of "trap 3" here,
-	so we check for both cases.
-
-	Older GCC versions emitted stack overflow checks after the SP
-	adjustments in both steps 3 and 4.  Starting with GCC 6, there is
-	at most one overflow check, which is placed before the first
-	stack adjustment for R2 CDX and after the first stack adjustment
-	otherwise.
-
-    The prologue instructions may be combined or interleaved with other
-    instructions.
-
-    To cope with all this variability we decode all the instructions
-    from the start of the prologue until we hit an instruction that
-    cannot possibly be a prologue instruction, such as a branch, call,
-    return, or epilogue instruction.  The prologue is considered to end
-    at the last instruction that can definitely be considered a
-    prologue instruction.  */
-
-static CORE_ADDR
-nios2_analyze_prologue (struct gdbarch *gdbarch, const CORE_ADDR start_pc,
-			const CORE_ADDR current_pc,
-			struct nios2_unwind_cache *cache,
-			const frame_info_ptr &this_frame)
-{
-  /* Maximum number of possibly-prologue instructions to check.
-     Note that this number should not be too large, else we can
-     potentially end up iterating through unmapped memory.  */
-  int ninsns, max_insns = 50;
-  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
-  unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach;
-
-  /* Does the frame set up the FP register?  */
-  int base_reg = 0;
-
-  struct reg_value *value = cache->reg_value;
-  struct reg_value temp_value[NIOS2_NUM_REGS];
-
-  /* Save the starting PC so we can correct the pc after running
-     through the prolog, using symbol info.  */
-  CORE_ADDR pc = start_pc;
-
-  /* Is this an exception handler?  */
-  int exception_handler = 0;
-
-  /* What was the original value of SP (or fake original value for
-     functions which switch stacks?  */
-  CORE_ADDR frame_high;
-
-  /* The last definitely-prologue instruction seen.  */
-  CORE_ADDR prologue_end;
-
-  /* Is this the innermost function?  */
-  int innermost = (this_frame ? (frame_relative_level (this_frame) == 0) : 1);
-
-  if (nios2_debug)
-    gdb_printf (gdb_stdlog,
-		"{ nios2_analyze_prologue start=%s, current=%s ",
-		paddress (gdbarch, start_pc),
-		paddress (gdbarch, current_pc));
-
-  /* Set up the default values of the registers.  */
-  nios2_setup_default (cache);
-
-  /* Find the prologue instructions.  */
-  prologue_end = start_pc;
-  for (ninsns = 0; ninsns < max_insns; ninsns++)
-    {
-      /* Present instruction.  */
-      uint32_t insn;
-      const struct nios2_opcode *op;
-      int ra, rb, rc, imm;
-      unsigned int uimm;
-      unsigned int reglist;
-      int wb, id, ret;
-      enum branch_condition cond;
-
-      if (pc == current_pc)
-	{
-	  /* When we reach the current PC we must save the current
-	     register state (for the backtrace) but keep analysing
-	     because there might be more to find out (eg. is this an
-	     exception handler).  */
-	  memcpy (temp_value, value, sizeof (temp_value));
-	  value = temp_value;
-	  if (nios2_debug)
-	    gdb_printf (gdb_stdlog, "*");
-	}
-
-      op = nios2_fetch_insn (gdbarch, pc, &insn);
-
-      /* Unknown opcode?  Stop scanning.  */
-      if (op == NULL)
-	break;
-      pc += op->size;
-
-      if (nios2_debug)
-	{
-	  if (op->size == 2)
-	    gdb_printf (gdb_stdlog, "[%04X]", insn & 0xffff);
-	  else
-	    gdb_printf (gdb_stdlog, "[%08X]", insn);
-	}
-
-      /* The following instructions can appear in the prologue.  */
-
-      if (nios2_match_add (insn, op, mach, &ra, &rb, &rc))
-	{
-	  /* ADD   rc, ra, rb  (also used for MOV) */
-	  if (rc == NIOS2_SP_REGNUM
-	      && rb == 0
-	      && value[ra].reg == cache->reg_saved[NIOS2_SP_REGNUM].basereg)
-	    {
-	      /* If the previous value of SP is available somewhere
-		 near the new stack pointer value then this is a
-		 stack switch.  */
-
-	      /* If any registers were saved on the stack before then
-		 we can't backtrace into them now.  */
-	      for (int i = 0 ; i < NIOS2_NUM_REGS ; i++)
-		{
-		  if (cache->reg_saved[i].basereg == NIOS2_SP_REGNUM)
-		    cache->reg_saved[i].basereg = -1;
-		  if (value[i].reg == NIOS2_SP_REGNUM)
-		    value[i].reg = -1;
-		}
-
-	      /* Create a fake "high water mark" 4 bytes above where SP
-		 was stored and fake up the registers to be consistent
-		 with that.  */
-	      value[NIOS2_SP_REGNUM].reg = NIOS2_SP_REGNUM;
-	      value[NIOS2_SP_REGNUM].offset
-		= (value[ra].offset
-		   - cache->reg_saved[NIOS2_SP_REGNUM].addr
-		   - 4);
-	      cache->reg_saved[NIOS2_SP_REGNUM].basereg = NIOS2_SP_REGNUM;
-	      cache->reg_saved[NIOS2_SP_REGNUM].addr = -4;
-	    }
-
-	  else if (rc == NIOS2_SP_REGNUM && ra == NIOS2_FP_REGNUM)
-	    /* This is setting SP from FP.  This only happens in the
-	       function epilogue.  */
-	    break;
-
-	  else if (rc != 0)
-	    {
-	      if (value[rb].reg == 0)
-		value[rc].reg = value[ra].reg;
-	      else if (value[ra].reg == 0)
-		value[rc].reg = value[rb].reg;
-	      else
-		value[rc].reg = -1;
-	      value[rc].offset = value[ra].offset + value[rb].offset;
-	    }
-
-	  /* The add/move is only considered a prologue instruction
-	     if the destination is SP or FP.  */
-	  if (rc == NIOS2_SP_REGNUM || rc == NIOS2_FP_REGNUM)
-	    prologue_end = pc;
-	}
-      
-      else if (nios2_match_sub (insn, op, mach, &ra, &rb, &rc))
-	{
-	  /* SUB   rc, ra, rb */
-	  if (rc == NIOS2_SP_REGNUM && rb == NIOS2_SP_REGNUM
-	      && value[rc].reg != 0)
-	    /* If we are decrementing the SP by a non-constant amount,
-	       this is alloca, not part of the prologue.  */
-	    break;
-	  else if (rc != 0)
-	    {
-	      if (value[rb].reg == 0)
-		value[rc].reg = value[ra].reg;
-	      else
-		value[rc].reg = -1;
-	      value[rc].offset = value[ra].offset - value[rb].offset;
-	    }
-	}
-
-      else if (nios2_match_addi (insn, op, mach, &ra, &rb, &imm))
-	{
-	  /* ADDI    rb, ra, imm */
-
-	  /* A positive stack adjustment has to be part of the epilogue.  */
-	  if (rb == NIOS2_SP_REGNUM
-	      && (imm > 0 || value[ra].reg != NIOS2_SP_REGNUM))
-	    break;
-
-	  /* Likewise restoring SP from FP.  */
-	  else if (rb == NIOS2_SP_REGNUM && ra == NIOS2_FP_REGNUM)
-	    break;
-
-	  if (rb != 0)
-	    {
-	      value[rb].reg    = value[ra].reg;
-	      value[rb].offset = value[ra].offset + imm;
-	    }
-
-	  /* The add is only considered a prologue instruction
-	     if the destination is SP or FP.  */
-	  if (rb == NIOS2_SP_REGNUM || rb == NIOS2_FP_REGNUM)
-	    prologue_end = pc;
-	}
-
-      else if (nios2_match_orhi (insn, op, mach, &ra, &rb, &uimm))
-	{
-	  /* ORHI  rb, ra, uimm   (also used for MOVHI) */
-	  if (rb != 0)
-	    {
-	      value[rb].reg    = (value[ra].reg == 0) ? 0 : -1;
-	      value[rb].offset = value[ra].offset | (uimm << 16);
-	    }
-	}
-
-      else if (nios2_match_stw (insn, op, mach, &ra, &rb, &imm))
-	{
-	  /* STW rb, imm(ra) */
-
-	  /* Are we storing the original value of a register to the stack?
-	     For exception handlers the value of EA-4 (return
-	     address from interrupts etc) is sometimes stored.  */
-	  int orig = value[rb].reg;
-	  if (orig > 0
-	      && (value[rb].offset == 0
-		  || (orig == NIOS2_EA_REGNUM && value[rb].offset == -4))
-	      && value[ra].reg == NIOS2_SP_REGNUM)
-	    {
-	      if (pc < current_pc)
-		{
-		  /* Save off callee saved registers.  */
-		  cache->reg_saved[orig].basereg = value[ra].reg;
-		  cache->reg_saved[orig].addr = value[ra].offset + imm;
-		}
-	      
-	      prologue_end = pc;
-	      
-	      if (orig == NIOS2_EA_REGNUM || orig == NIOS2_ESTATUS_REGNUM)
-		exception_handler = 1;
-	    }
-	  else
-	    /* Non-stack memory writes cannot appear in the prologue.  */
-	    break;
-	}
-
-      else if (nios2_match_stwm (insn, op, mach,
-				 &reglist, &ra, &imm, &wb, &id))
-	{
-	  /* PUSH.N {reglist}, adjust
-	     or
-	     STWM {reglist}, --(SP)[, writeback] */
-	  int off = 0;
-
-	  if (ra != NIOS2_SP_REGNUM || id != 0)
-	    /* This is a non-stack-push memory write and cannot be
-	       part of the prologue.  */
-	    break;
-
-	  for (int i = 31; i >= 0; i--)
-	    if (reglist & (1 << i))
-	      {
-		int orig = value[i].reg;
-		
-		off += 4;
-		if (orig > 0 && value[i].offset == 0 && pc < current_pc)
-		  {
-		    cache->reg_saved[orig].basereg
-		      = value[NIOS2_SP_REGNUM].reg;
-		    cache->reg_saved[orig].addr
-		      = value[NIOS2_SP_REGNUM].offset - off;
-		  }
-	      }
-
-	  if (wb)
-	    value[NIOS2_SP_REGNUM].offset -= off;
-	  value[NIOS2_SP_REGNUM].offset -= imm;
-
-	  prologue_end = pc;
-	}
-
-      else if (nios2_match_rdctl (insn, op, mach, &ra, &rc))
-	{
-	  /* RDCTL rC, ctlN
-	     This can appear in exception handlers in combination with
-	     a subsequent save to the stack frame.  */
-	  if (rc != 0)
-	    {
-	      value[rc].reg    = NIOS2_STATUS_REGNUM + ra;
-	      value[rc].offset = 0;
-	    }
-	}
-
-      else if (nios2_match_calli (insn, op, mach, &uimm))
-	{
-	  if (value[8].reg == NIOS2_RA_REGNUM
-	      && value[8].offset == 0
-	      && value[NIOS2_SP_REGNUM].reg == NIOS2_SP_REGNUM
-	      && value[NIOS2_SP_REGNUM].offset == 0)
-	    {
-	      /* A CALL instruction.  This is treated as a call to mcount
-		 if ra has been stored into r8 beforehand and if it's
-		 before the stack adjust.
-		 Note mcount corrupts r2-r3, r9-r15 & ra.  */
-	      for (int i = 2 ; i <= 3 ; i++)
-		value[i].reg = -1;
-	      for (int i = 9 ; i <= 15 ; i++)
-		value[i].reg = -1;
-	      value[NIOS2_RA_REGNUM].reg = -1;
-
-	      prologue_end = pc;
-	    }
-
-	  /* Other calls are not part of the prologue.  */
-	  else
-	    break;
-	}
-
-      else if (nios2_match_branch (insn, op, mach, &ra, &rb, &imm, &cond))
-	{
-	  /* Branches not involving a stack overflow check aren't part of
-	     the prologue.  */
-	  if (ra != NIOS2_SP_REGNUM)
-	    break;
-	  else if (cond == branch_geu)
-	    {
-	      /* BGEU sp, rx, +8
-		 TRAP 3  (or BREAK 3)
-		 This instruction sequence is used in stack checking;
-		 we can ignore it.  */
-	      unsigned int next_insn;
-	      const struct nios2_opcode *next_op
-		= nios2_fetch_insn (gdbarch, pc, &next_insn);
-	      if (next_op != NULL
-		  && (nios2_match_trap (next_insn, op, mach, &uimm)
-		      || nios2_match_break (next_insn, op, mach, &uimm)))
-		pc += next_op->size;
-	      else
-		break;
-	    }
-	  else if (cond == branch_ltu)
-	    {
-	      /* BLTU sp, rx, .Lstackoverflow
-		 If the location branched to holds a TRAP or BREAK
-		 instruction then this is also stack overflow detection.  */
-	      unsigned int next_insn;
-	      const struct nios2_opcode *next_op
-		= nios2_fetch_insn (gdbarch, pc + imm, &next_insn);
-	      if (next_op != NULL
-		  && (nios2_match_trap (next_insn, op, mach, &uimm)
-		      || nios2_match_break (next_insn, op, mach, &uimm)))
-		;
-	      else
-		break;
-	    }
-	  else
-	    break;
-	}
-
-      /* All other calls, jumps, returns, TRAPs, or BREAKs terminate
-	 the prologue.  */
-      else if (nios2_match_callr (insn, op, mach, &ra)
-	       || nios2_match_jmpr (insn, op, mach, &ra)
-	       || nios2_match_jmpi (insn, op, mach, &uimm)
-	       || (nios2_match_ldwm (insn, op, mach, &reglist, &ra,
-				     &imm, &wb, &id, &ret)
-		   && ret)
-	       || nios2_match_trap (insn, op, mach, &uimm)
-	       || nios2_match_break (insn, op, mach, &uimm))
-	break;
-    }
-
-  /* If THIS_FRAME is NULL, we are being called from skip_prologue
-     and are only interested in the PROLOGUE_END value, so just
-     return that now and skip over the cache updates, which depend
-     on having frame information.  */
-  if (this_frame == NULL)
-    return prologue_end;
-
-  /* If we are in the function epilogue and have already popped
-     registers off the stack in preparation for returning, then we
-     want to go back to the original register values.  */
-  if (innermost && nios2_in_epilogue_p (gdbarch, current_pc, start_pc))
-    nios2_setup_default (cache);
-
-  /* Exception handlers use a different return address register.  */
-  if (exception_handler)
-    cache->return_regnum = NIOS2_EA_REGNUM;
-
-  if (nios2_debug)
-    gdb_printf (gdb_stdlog, "\n-> retreg=%d, ", cache->return_regnum);
-
-  if (cache->reg_value[NIOS2_FP_REGNUM].reg == NIOS2_SP_REGNUM)
-    /* If the FP now holds an offset from the CFA then this is a
-       normal frame which uses the frame pointer.  */
-    base_reg = NIOS2_FP_REGNUM;
-  else if (cache->reg_value[NIOS2_SP_REGNUM].reg == NIOS2_SP_REGNUM)
-    /* FP doesn't hold an offset from the CFA.  If SP still holds an
-       offset from the CFA then we might be in a function which omits
-       the frame pointer, or we might be partway through the prologue.
-       In both cases we can find the CFA using SP.  */
-    base_reg = NIOS2_SP_REGNUM;
-  else
-    {
-      /* Somehow the stack pointer has been corrupted.
-	 We can't return.  */
-      if (nios2_debug)
-	gdb_printf (gdb_stdlog, "<can't reach cfa> }\n");
-      return 0;
-    }
-
-  if (cache->reg_value[base_reg].offset == 0
-      || cache->reg_saved[NIOS2_RA_REGNUM].basereg != NIOS2_SP_REGNUM
-      || cache->reg_saved[cache->return_regnum].basereg != NIOS2_SP_REGNUM)
-    {
-      /* If the frame didn't adjust the stack, didn't save RA or
-	 didn't save EA in an exception handler then it must either
-	 be a leaf function (doesn't call any other functions) or it
-	 can't return.  If it has called another function then it
-	 can't be a leaf, so set base == 0 to indicate that we can't
-	 backtrace past it.  */
-
-      if (!innermost)
-	{
-	  /* If it isn't the innermost function then it can't be a
-	     leaf, unless it was interrupted.  Check whether RA for
-	     this frame is the same as PC.  If so then it probably
-	     wasn't interrupted.  */
-	  CORE_ADDR ra
-	    = get_frame_register_unsigned (this_frame, NIOS2_RA_REGNUM);
-
-	  if (ra == current_pc)
-	    {
-	      if (nios2_debug)
-		gdb_printf
-		  (gdb_stdlog,
-		   "<noreturn ADJUST %s, r31@r%d+?>, r%d@r%d+?> }\n",
-		   paddress (gdbarch, cache->reg_value[base_reg].offset),
-		   cache->reg_saved[NIOS2_RA_REGNUM].basereg,
-		   cache->return_regnum,
-		   cache->reg_saved[cache->return_regnum].basereg);
-	      return 0;
-	    }
-	}
-    }
-
-  /* Get the value of whichever register we are using for the
-     base.  */
-  cache->base = get_frame_register_unsigned (this_frame, base_reg);
-
-  /* What was the value of SP at the start of this function (or just
-     after the stack switch).  */
-  frame_high = cache->base - cache->reg_value[base_reg].offset;
-
-  /* Adjust all the saved registers such that they contain addresses
-     instead of offsets.  */
-  for (int i = 0; i < NIOS2_NUM_REGS; i++)
-    if (cache->reg_saved[i].basereg == NIOS2_SP_REGNUM)
-      {
-	cache->reg_saved[i].basereg = NIOS2_Z_REGNUM;
-	cache->reg_saved[i].addr += frame_high;
-      }
-
-  for (int i = 0; i < NIOS2_NUM_REGS; i++)
-    if (cache->reg_saved[i].basereg == NIOS2_GP_REGNUM)
-      {
-	CORE_ADDR gp = get_frame_register_unsigned (this_frame,
-						    NIOS2_GP_REGNUM);
-
-	for ( ; i < NIOS2_NUM_REGS; i++)
-	  if (cache->reg_saved[i].basereg == NIOS2_GP_REGNUM)
-	    {
-	      cache->reg_saved[i].basereg = NIOS2_Z_REGNUM;
-	      cache->reg_saved[i].addr += gp;
-	    }
-      }
-
-  /* Work out what the value of SP was on the first instruction of
-     this function.  If we didn't switch stacks then this can be
-     trivially computed from the base address.  */
-  if (cache->reg_saved[NIOS2_SP_REGNUM].basereg == NIOS2_Z_REGNUM)
-    cache->cfa
-      = read_memory_unsigned_integer (cache->reg_saved[NIOS2_SP_REGNUM].addr,
-				      4, byte_order);
-  else
-    cache->cfa = frame_high;
-
-  /* Exception handlers restore ESTATUS into STATUS.  */
-  if (exception_handler)
-    {
-      cache->reg_saved[NIOS2_STATUS_REGNUM]
-	= cache->reg_saved[NIOS2_ESTATUS_REGNUM];
-      cache->reg_saved[NIOS2_ESTATUS_REGNUM].basereg = -1;
-    }
-
-  if (nios2_debug)
-    gdb_printf (gdb_stdlog, "cfa=%s }\n",
-		paddress (gdbarch, cache->cfa));
-
-  return prologue_end;
-}
-
-/* Implement the skip_prologue gdbarch hook.  */
-
-static CORE_ADDR
-nios2_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc)
-{
-  CORE_ADDR func_addr;
-
-  struct nios2_unwind_cache cache;
-
-  /* See if we can determine the end of the prologue via the symbol
-     table.  If so, then return either PC, or the PC after the
-     prologue, whichever is greater.  */
-  if (find_pc_partial_function (start_pc, NULL, &func_addr, NULL))
-    {
-      CORE_ADDR post_prologue_pc
-	= skip_prologue_using_sal (gdbarch, func_addr);
-
-      if (post_prologue_pc != 0)
-	return std::max (start_pc, post_prologue_pc);
-    }
-
-  /* Prologue analysis does the rest....  */
-  nios2_init_cache (&cache, start_pc);
-  return nios2_analyze_prologue (gdbarch, start_pc, start_pc, &cache, NULL);
-}
-
-/* Implement the breakpoint_kind_from_pc gdbarch method.  */
-
-static int
-nios2_breakpoint_kind_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr)
-{
-  unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach;
-
-  if (mach == bfd_mach_nios2r2)
-    {
-      unsigned int insn;
-      const struct nios2_opcode *op
-	= nios2_fetch_insn (gdbarch, *pcptr, &insn);
-
-      if (op && op->size == NIOS2_CDX_OPCODE_SIZE)
-	return NIOS2_CDX_OPCODE_SIZE;
-      else
-	return NIOS2_OPCODE_SIZE;
-    }
-  else
-    return NIOS2_OPCODE_SIZE;
-}
-
-/* Implement the sw_breakpoint_from_kind gdbarch method.  */
-
-static const gdb_byte *
-nios2_sw_breakpoint_from_kind (struct gdbarch *gdbarch, int kind, int *size)
-{
-/* The Nios II ABI for Linux says: "Userspace programs should not use
-   the break instruction and userspace debuggers should not insert
-   one." and "Userspace breakpoints are accomplished using the trap
-   instruction with immediate operand 31 (all ones)."
-
-   So, we use "trap 31" consistently as the breakpoint on bare-metal
-   as well as Linux targets.  */
-
-  /* R2 trap encoding:
-     ((0x2d << 26) | (0x1f << 21) | (0x1d << 16) | (0x20 << 0))
-     0xb7fd0020
-     CDX trap.n encoding:
-     ((0xd << 12) | (0x1f << 6) | (0x9 << 0))
-     0xd7c9
-     Note that code is always little-endian on R2.  */
-  *size = kind;
-
-  if (kind == NIOS2_CDX_OPCODE_SIZE)
-    {
-      static const gdb_byte cdx_breakpoint_le[] = {0xc9, 0xd7};
-
-      return cdx_breakpoint_le;
-    }
-  else
-    {
-      unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach;
-
-      if (mach == bfd_mach_nios2r2)
-	{
-	  static const gdb_byte r2_breakpoint_le[] = {0x20, 0x00, 0xfd, 0xb7};
-
-	  return r2_breakpoint_le;
-	}
-      else
-	{
-	  enum bfd_endian byte_order_for_code
-	    = gdbarch_byte_order_for_code (gdbarch);
-	  /* R1 trap encoding:
-	     ((0x1d << 17) | (0x2d << 11) | (0x1f << 6) | (0x3a << 0))
-	     0x003b6ffa */
-	  static const gdb_byte r1_breakpoint_le[] = {0xfa, 0x6f, 0x3b, 0x0};
-	  static const gdb_byte r1_breakpoint_be[] = {0x0, 0x3b, 0x6f, 0xfa};
-
-	  if (byte_order_for_code == BFD_ENDIAN_BIG)
-	    return r1_breakpoint_be;
-	  else
-	    return r1_breakpoint_le;
-	}
-    }
-}
-
-/* Implement the frame_align gdbarch method.  */
-
-static CORE_ADDR
-nios2_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
-{
-  return align_down (addr, 4);
-}
-
-
-/* Implement the return_value gdbarch method.  */
-
-static enum return_value_convention
-nios2_return_value (struct gdbarch *gdbarch, struct value *function,
-		    struct type *type, struct regcache *regcache,
-		    gdb_byte *readbuf, const gdb_byte *writebuf)
-{
-  if (type->length () > 8)
-    return RETURN_VALUE_STRUCT_CONVENTION;
-
-  if (readbuf)
-    nios2_extract_return_value (gdbarch, type, regcache, readbuf);
-  if (writebuf)
-    nios2_store_return_value (gdbarch, type, regcache, writebuf);
-
-  return RETURN_VALUE_REGISTER_CONVENTION;
-}
-
-/* Implement the push_dummy_call gdbarch method.  */
-
-static CORE_ADDR
-nios2_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
-		       struct regcache *regcache, CORE_ADDR bp_addr,
-		       int nargs, struct value **args, CORE_ADDR sp,
-		       function_call_return_method return_method,
-		       CORE_ADDR struct_addr)
-{
-  int argreg;
-  int argnum;
-  int arg_space = 0;
-  int stack_offset = 0;
-  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
-
-  /* Set the return address register to point to the entry point of
-     the program, where a breakpoint lies in wait.  */
-  regcache_cooked_write_signed (regcache, NIOS2_RA_REGNUM, bp_addr);
-
-  /* Now make space on the stack for the args.  */
-  for (argnum = 0; argnum < nargs; argnum++)
-    arg_space += align_up (args[argnum]->type ()->length (), 4);
-  sp -= arg_space;
-
-  /* Initialize the register pointer.  */
-  argreg = NIOS2_FIRST_ARGREG;
-
-  /* The struct_return pointer occupies the first parameter-passing
-     register.  */
-  if (return_method == return_method_struct)
-    regcache_cooked_write_unsigned (regcache, argreg++, struct_addr);
-
-  /* Now load as many as possible of the first arguments into
-     registers, and push the rest onto the stack.  Loop through args
-     from first to last.  */
-  for (argnum = 0; argnum < nargs; argnum++)
-    {
-      const gdb_byte *val;
-      struct value *arg = args[argnum];
-      struct type *arg_type = check_typedef (arg->type ());
-      int len = arg_type->length ();
-
-      val = arg->contents ().data ();
-
-      /* Copy the argument to general registers or the stack in
-	 register-sized pieces.  Large arguments are split between
-	 registers and stack.  */
-      while (len > 0)
-	{
-	  int partial_len = (len < 4 ? len : 4);
-
-	  if (argreg <= NIOS2_LAST_ARGREG)
-	    {
-	      /* The argument is being passed in a register.  */
-	      CORE_ADDR regval = extract_unsigned_integer (val, partial_len,
-							   byte_order);
-
-	      regcache_cooked_write_unsigned (regcache, argreg, regval);
-	      argreg++;
-	    }
-	  else
-	    {
-	      /* The argument is being passed on the stack.  */
-	      CORE_ADDR addr = sp + stack_offset;
-
-	      write_memory (addr, val, partial_len);
-	      stack_offset += align_up (partial_len, 4);
-	    }
-
-	  len -= partial_len;
-	  val += partial_len;
-	}
-    }
-
-  regcache_cooked_write_signed (regcache, NIOS2_SP_REGNUM, sp);
-
-  /* Return adjusted stack pointer.  */
-  return sp;
-}
-
-/* Implement the unwind_pc gdbarch method.  */
-
-static CORE_ADDR
-nios2_unwind_pc (struct gdbarch *gdbarch, const frame_info_ptr &next_frame)
-{
-  gdb_byte buf[4];
-
-  frame_unwind_register (next_frame, NIOS2_PC_REGNUM, buf);
-  return extract_typed_address (buf, builtin_type (gdbarch)->builtin_func_ptr);
-}
-
-/* Use prologue analysis to fill in the register cache
-   *THIS_PROLOGUE_CACHE for THIS_FRAME.  This function initializes
-   *THIS_PROLOGUE_CACHE first.  */
-
-static struct nios2_unwind_cache *
-nios2_frame_unwind_cache (const frame_info_ptr &this_frame,
-			  void **this_prologue_cache)
-{
-  struct gdbarch *gdbarch = get_frame_arch (this_frame);
-  CORE_ADDR current_pc;
-  struct nios2_unwind_cache *cache;
-
-  if (*this_prologue_cache)
-    return (struct nios2_unwind_cache *) *this_prologue_cache;
-
-  cache = FRAME_OBSTACK_ZALLOC (struct nios2_unwind_cache);
-  *this_prologue_cache = cache;
-
-  /* Zero all fields.  */
-  nios2_init_cache (cache, get_frame_func (this_frame));
-
-  /* Prologue analysis does the rest...  */
-  current_pc = get_frame_pc (this_frame);
-  if (cache->pc != 0)
-    nios2_analyze_prologue (gdbarch, cache->pc, current_pc, cache, this_frame);
-
-  return cache;
-}
-
-/* Implement the this_id function for the normal unwinder.  */
-
-static void
-nios2_frame_this_id (const frame_info_ptr &this_frame, void **this_cache,
-		     struct frame_id *this_id)
-{
-  struct nios2_unwind_cache *cache =
-    nios2_frame_unwind_cache (this_frame, this_cache);
-
-  /* This marks the outermost frame.  */
-  if (cache->base == 0)
-    return;
-
-  *this_id = frame_id_build (cache->cfa, cache->pc);
-}
-
-/* Implement the prev_register function for the normal unwinder.  */
-
-static struct value *
-nios2_frame_prev_register (const frame_info_ptr &this_frame, void **this_cache,
-			   int regnum)
-{
-  struct nios2_unwind_cache *cache =
-    nios2_frame_unwind_cache (this_frame, this_cache);
-
-  gdb_assert (regnum >= 0 && regnum < NIOS2_NUM_REGS);
-
-  /* The PC of the previous frame is stored in the RA register of
-     the current frame.  Frob regnum so that we pull the value from
-     the correct place.  */
-  if (regnum == NIOS2_PC_REGNUM)
-    regnum = cache->return_regnum;
-
-  if (regnum == NIOS2_SP_REGNUM && cache->cfa)
-    return frame_unwind_got_constant (this_frame, regnum, cache->cfa);
-
-  /* If we've worked out where a register is stored then load it from
-     there.  */
-  if (cache->reg_saved[regnum].basereg == NIOS2_Z_REGNUM)
-    return frame_unwind_got_memory (this_frame, regnum,
-				    cache->reg_saved[regnum].addr);
-
-  return frame_unwind_got_register (this_frame, regnum, regnum);
-}
-
-/* Implement the this_base, this_locals, and this_args hooks
-   for the normal unwinder.  */
-
-static CORE_ADDR
-nios2_frame_base_address (const frame_info_ptr &this_frame, void **this_cache)
-{
-  struct nios2_unwind_cache *info
-    = nios2_frame_unwind_cache (this_frame, this_cache);
-
-  return info->base;
-}
-
-/* Data structures for the normal prologue-analysis-based
-   unwinder.  */
-
-static const struct frame_unwind nios2_frame_unwind =
-{
-  "nios2 prologue",
-  NORMAL_FRAME,
-  default_frame_unwind_stop_reason,
-  nios2_frame_this_id,
-  nios2_frame_prev_register,
-  NULL,
-  default_frame_sniffer
-};
-
-static const struct frame_base nios2_frame_base =
-{
-  &nios2_frame_unwind,
-  nios2_frame_base_address,
-  nios2_frame_base_address,
-  nios2_frame_base_address
-};
-
-/* Fill in the register cache *THIS_CACHE for THIS_FRAME for use
-   in the stub unwinder.  */
-
-static struct trad_frame_cache *
-nios2_stub_frame_cache (const frame_info_ptr &this_frame, void **this_cache)
-{
-  CORE_ADDR pc;
-  CORE_ADDR start_addr;
-  CORE_ADDR stack_addr;
-  struct trad_frame_cache *this_trad_cache;
-  struct gdbarch *gdbarch = get_frame_arch (this_frame);
-
-  if (*this_cache != NULL)
-    return (struct trad_frame_cache *) *this_cache;
-  this_trad_cache = trad_frame_cache_zalloc (this_frame);
-  *this_cache = this_trad_cache;
-
-  /* The return address is in the link register.  */
-  trad_frame_set_reg_realreg (this_trad_cache,
-			      gdbarch_pc_regnum (gdbarch),
-			      NIOS2_RA_REGNUM);
-
-  /* Frame ID, since it's a frameless / stackless function, no stack
-     space is allocated and SP on entry is the current SP.  */
-  pc = get_frame_pc (this_frame);
-  find_pc_partial_function (pc, NULL, &start_addr, NULL);
-  stack_addr = get_frame_register_unsigned (this_frame, NIOS2_SP_REGNUM);
-  trad_frame_set_id (this_trad_cache, frame_id_build (start_addr, stack_addr));
-  /* Assume that the frame's base is the same as the stack pointer.  */
-  trad_frame_set_this_base (this_trad_cache, stack_addr);
-
-  return this_trad_cache;
-}
-
-/* Implement the this_id function for the stub unwinder.  */
-
-static void
-nios2_stub_frame_this_id (const frame_info_ptr &this_frame, void **this_cache,
-			  struct frame_id *this_id)
-{
-  struct trad_frame_cache *this_trad_cache
-    = nios2_stub_frame_cache (this_frame, this_cache);
-
-  trad_frame_get_id (this_trad_cache, this_id);
-}
-
-/* Implement the prev_register function for the stub unwinder.  */
-
-static struct value *
-nios2_stub_frame_prev_register (const frame_info_ptr &this_frame,
-				void **this_cache, int regnum)
-{
-  struct trad_frame_cache *this_trad_cache
-    = nios2_stub_frame_cache (this_frame, this_cache);
-
-  return trad_frame_get_register (this_trad_cache, this_frame, regnum);
-}
-
-/* Implement the sniffer function for the stub unwinder.
-   This unwinder is used for cases where the normal
-   prologue-analysis-based unwinder can't work,
-   such as PLT stubs.  */
-
-static int
-nios2_stub_frame_sniffer (const struct frame_unwind *self,
-			  const frame_info_ptr &this_frame, void **cache)
-{
-  gdb_byte dummy[4];
-  CORE_ADDR pc = get_frame_address_in_block (this_frame);
-
-  /* Use the stub unwinder for unreadable code.  */
-  if (target_read_memory (get_frame_pc (this_frame), dummy, 4) != 0)
-    return 1;
-
-  if (in_plt_section (pc))
-    return 1;
-
-  return 0;
-}
-
-/* Define the data structures for the stub unwinder.  */
-
-static const struct frame_unwind nios2_stub_frame_unwind =
-{
-  "nios2 stub",
-  NORMAL_FRAME,
-  default_frame_unwind_stop_reason,
-  nios2_stub_frame_this_id,
-  nios2_stub_frame_prev_register,
-  NULL,
-  nios2_stub_frame_sniffer
-};
-
-
-
-/* Determine where to set a single step breakpoint while considering
-   branch prediction.  */
-
-static CORE_ADDR
-nios2_get_next_pc (struct regcache *regcache, CORE_ADDR pc)
-{
-  struct gdbarch *gdbarch = regcache->arch ();
-  nios2_gdbarch_tdep *tdep = gdbarch_tdep<nios2_gdbarch_tdep> (gdbarch);
-  unsigned long mach = gdbarch_bfd_arch_info (gdbarch)->mach;
-  unsigned int insn;
-  const struct nios2_opcode *op = nios2_fetch_insn (gdbarch, pc, &insn);
-  int ra;
-  int rb;
-  int imm;
-  unsigned int uimm;
-  int wb, id, ret;
-  enum branch_condition cond;
-
-  /* Do something stupid if we can't disassemble the insn at pc.  */
-  if (op == NULL)
-    return pc + NIOS2_OPCODE_SIZE;
-    
-  if (nios2_match_branch (insn, op, mach, &ra, &rb, &imm, &cond))
-    {
-      int ras = regcache_raw_get_signed (regcache, ra);
-      int rbs = regcache_raw_get_signed (regcache, rb);
-      unsigned int rau = regcache_raw_get_unsigned (regcache, ra);
-      unsigned int rbu = regcache_raw_get_unsigned (regcache, rb);
-
-      pc += op->size;
-      switch (cond)
-	{
-	case branch_none:
-	  pc += imm;
-	  break;
-	case branch_eq:
-	  if (ras == rbs)
-	    pc += imm;
-	  break;
-	case branch_ne:
-	  if (ras != rbs)
-	    pc += imm;
-	  break;
-	case branch_ge:
-	  if (ras >= rbs)
-	    pc += imm;
-	  break;
-	case branch_geu:
-	  if (rau >= rbu)
-	    pc += imm;
-	  break;
-	case branch_lt:
-	  if (ras < rbs)
-	    pc += imm;
-	  break;
-	case branch_ltu:
-	  if (rau < rbu)
-	    pc += imm;
-	  break;
-	default:
-	  break;
-	}
-    }
-
-  else if (nios2_match_jmpi (insn, op, mach, &uimm))
-    pc = (pc & 0xf0000000) | uimm;
-  else if (nios2_match_calli (insn, op, mach, &uimm))
-    {
-      CORE_ADDR callto = (pc & 0xf0000000) | uimm;
-      if (tdep->is_kernel_helper != NULL
-	  && tdep->is_kernel_helper (callto))
-	/* Step over call to kernel helper, which we cannot debug
-	   from user space.  */
-	pc += op->size;
-      else
-	pc = callto;
-    }
-
-  else if (nios2_match_jmpr (insn, op, mach, &ra))
-    pc = regcache_raw_get_unsigned (regcache, ra);
-  else if (nios2_match_callr (insn, op, mach, &ra))
-    {
-      CORE_ADDR callto = regcache_raw_get_unsigned (regcache, ra);
-      if (tdep->is_kernel_helper != NULL
-	  && tdep->is_kernel_helper (callto))
-	/* Step over call to kernel helper.  */
-	pc += op->size;
-      else
-	pc = callto;
-    }
-
-  else if (nios2_match_ldwm (insn, op, mach, &uimm, &ra, &imm, &wb, &id, &ret)
-	   && ret)
-    {
-      /* If ra is in the reglist, we have to use the value saved in the
-	 stack frame rather than the current value.  */
-      if (uimm & (1 << NIOS2_RA_REGNUM))
-	pc = nios2_unwind_pc (gdbarch, get_current_frame ());
-      else
-	pc = regcache_raw_get_unsigned (regcache, NIOS2_RA_REGNUM);
-    }
-
-  else if (nios2_match_trap (insn, op, mach, &uimm) && uimm == 0)
-    {
-      if (tdep->syscall_next_pc != NULL)
-	return tdep->syscall_next_pc (get_current_frame (), op);
-    }
-
-  else
-    pc += op->size;
-
-  return pc;
-}
-
-/* Implement the software_single_step gdbarch method.  */
-
-static std::vector<CORE_ADDR>
-nios2_software_single_step (struct regcache *regcache)
-{
-  CORE_ADDR next_pc = nios2_get_next_pc (regcache, regcache_read_pc (regcache));
-
-  return {next_pc};
-}
-
-/* Implement the get_longjump_target gdbarch method.  */
-
-static int
-nios2_get_longjmp_target (const frame_info_ptr &frame, CORE_ADDR *pc)
-{
-  struct gdbarch *gdbarch = get_frame_arch (frame);
-  nios2_gdbarch_tdep *tdep = gdbarch_tdep<nios2_gdbarch_tdep> (gdbarch);
-  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
-  CORE_ADDR jb_addr = get_frame_register_unsigned (frame, NIOS2_R4_REGNUM);
-  gdb_byte buf[4];
-
-  if (target_read_memory (jb_addr + (tdep->jb_pc * 4), buf, 4))
-    return 0;
-
-  *pc = extract_unsigned_integer (buf, 4, byte_order);
-  return 1;
-}
-
-/* Implement the type_align gdbarch function.  */
-
-static ULONGEST
-nios2_type_align (struct gdbarch *gdbarch, struct type *type)
-{
-  switch (type->code ())
-    {
-    case TYPE_CODE_PTR:
-    case TYPE_CODE_FUNC:
-    case TYPE_CODE_FLAGS:
-    case TYPE_CODE_INT:
-    case TYPE_CODE_RANGE:
-    case TYPE_CODE_FLT:
-    case TYPE_CODE_ENUM:
-    case TYPE_CODE_REF:
-    case TYPE_CODE_RVALUE_REF:
-    case TYPE_CODE_CHAR:
-    case TYPE_CODE_BOOL:
-    case TYPE_CODE_DECFLOAT:
-    case TYPE_CODE_METHODPTR:
-    case TYPE_CODE_MEMBERPTR:
-      type = check_typedef (type);
-      return std::min<ULONGEST> (4, type->length ());
-    default:
-      return 0;
-    }
-}
-
-/* Implement the gcc_target_options gdbarch method.  */
-static std::string
-nios2_gcc_target_options (struct gdbarch *gdbarch)
-{
-  /* GCC doesn't know "-m32".  */
-  return {};
-}
-
-/* Initialize the Nios II gdbarch.  */
-
-static struct gdbarch *
-nios2_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
-{
-  int i;
-  tdesc_arch_data_up tdesc_data;
-  const struct target_desc *tdesc = info.target_desc;
-
-  if (!tdesc_has_registers (tdesc))
-    /* Pick a default target description.  */
-    tdesc = tdesc_nios2;
-
-  /* Check any target description for validity.  */
-  if (tdesc_has_registers (tdesc))
-    {
-      const struct tdesc_feature *feature;
-      int valid_p;
-
-      feature = tdesc_find_feature (tdesc, "org.gnu.gdb.nios2.cpu");
-      if (feature == NULL)
-	return NULL;
-
-      tdesc_data = tdesc_data_alloc ();
-
-      valid_p = 1;
-      
-      for (i = 0; i < NIOS2_NUM_REGS; i++)
-	valid_p &= tdesc_numbered_register (feature, tdesc_data.get (), i,
-					    nios2_reg_names[i]);
-
-      if (!valid_p)
-	return NULL;
-    }
-
-  /* Find a candidate among the list of pre-declared architectures.  */
-  arches = gdbarch_list_lookup_by_info (arches, &info);
-  if (arches != NULL)
-    return arches->gdbarch;
-
-  /* None found, create a new architecture from the information
-     provided.  */
-  gdbarch *gdbarch
-    = gdbarch_alloc (&info, gdbarch_tdep_up (new nios2_gdbarch_tdep));
-  nios2_gdbarch_tdep *tdep = gdbarch_tdep<nios2_gdbarch_tdep> (gdbarch);
-
-  /* longjmp support not enabled by default.  */
-  tdep->jb_pc = -1;
-
-  /* Data type sizes.  */
-  set_gdbarch_ptr_bit (gdbarch, 32);
-  set_gdbarch_addr_bit (gdbarch, 32);
-  set_gdbarch_short_bit (gdbarch, 16);
-  set_gdbarch_int_bit (gdbarch, 32);
-  set_gdbarch_long_bit (gdbarch, 32);
-  set_gdbarch_long_long_bit (gdbarch, 64);
-  set_gdbarch_float_bit (gdbarch, 32);
-  set_gdbarch_double_bit (gdbarch, 64);
-
-  set_gdbarch_type_align (gdbarch, nios2_type_align);
-
-  set_gdbarch_float_format (gdbarch, floatformats_ieee_single);
-  set_gdbarch_double_format (gdbarch, floatformats_ieee_double);
-
-  /* The register set.  */
-  set_gdbarch_num_regs (gdbarch, NIOS2_NUM_REGS);
-  set_gdbarch_sp_regnum (gdbarch, NIOS2_SP_REGNUM);
-  set_gdbarch_pc_regnum (gdbarch, NIOS2_PC_REGNUM);	/* Pseudo register PC */
-
-  set_gdbarch_register_name (gdbarch, nios2_register_name);
-  set_gdbarch_register_type (gdbarch, nios2_register_type);
-
-  /* Provide register mappings for stabs and dwarf2.  */
-  set_gdbarch_stab_reg_to_regnum (gdbarch, nios2_dwarf_reg_to_regnum);
-  set_gdbarch_dwarf2_reg_to_regnum (gdbarch, nios2_dwarf_reg_to_regnum);
-
-  set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
-
-  /* Call dummy code.  */
-  set_gdbarch_frame_align (gdbarch, nios2_frame_align);
-
-  set_gdbarch_return_value (gdbarch, nios2_return_value);
-
-  set_gdbarch_skip_prologue (gdbarch, nios2_skip_prologue);
-  set_gdbarch_stack_frame_destroyed_p (gdbarch, nios2_stack_frame_destroyed_p);
-  set_gdbarch_breakpoint_kind_from_pc (gdbarch, nios2_breakpoint_kind_from_pc);
-  set_gdbarch_sw_breakpoint_from_kind (gdbarch, nios2_sw_breakpoint_from_kind);
-
-  set_gdbarch_unwind_pc (gdbarch, nios2_unwind_pc);
-
-  /* The dwarf2 unwinder will normally produce the best results if
-     the debug information is available, so register it first.  */
-  dwarf2_append_unwinders (gdbarch);
-  frame_unwind_append_unwinder (gdbarch, &nios2_stub_frame_unwind);
-  frame_unwind_append_unwinder (gdbarch, &nios2_frame_unwind);
-
-  /* Single stepping.  */
-  set_gdbarch_software_single_step (gdbarch, nios2_software_single_step);
-
-  /* Target options for compile.  */
-  set_gdbarch_gcc_target_options (gdbarch, nios2_gcc_target_options);
-
-  /* Hook in ABI-specific overrides, if they have been registered.  */
-  gdbarch_init_osabi (info, gdbarch);
-
-  if (tdep->jb_pc >= 0)
-    set_gdbarch_get_longjmp_target (gdbarch, nios2_get_longjmp_target);
-
-  frame_base_set_default (gdbarch, &nios2_frame_base);
-
-  /* Enable inferior call support.  */
-  set_gdbarch_push_dummy_call (gdbarch, nios2_push_dummy_call);
-
-  if (tdesc_data != nullptr)
-    tdesc_use_registers (gdbarch, tdesc, std::move (tdesc_data));
-
-  return gdbarch;
-}
-
-void _initialize_nios2_tdep ();
-void
-_initialize_nios2_tdep ()
-{
-  gdbarch_register (bfd_arch_nios2, nios2_gdbarch_init, NULL);
-  initialize_tdesc_nios2 ();
-
-  /* Allow debugging this file's internals.  */
-  add_setshow_boolean_cmd ("nios2", class_maintenance, &nios2_debug,
-			   _("Set Nios II debugging."),
-			   _("Show Nios II debugging."),
-			   _("When on, Nios II specific debugging is enabled."),
-			   NULL,
-			   NULL,
-			   &setdebuglist, &showdebuglist);
-}
diff --git a/gdb/nios2-tdep.h b/gdb/nios2-tdep.h
deleted file mode 100644
index 57e0de7..0000000
--- a/gdb/nios2-tdep.h
+++ /dev/null
@@ -1,90 +0,0 @@
-/* Target-dependent header for the Nios II architecture, for GDB.
-   Copyright (C) 2012-2024 Free Software Foundation, Inc.
-   Contributed by Mentor Graphics, Inc.
-
-   This file is part of GDB.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program 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 a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#ifndef NIOS2_TDEP_H
-#define NIOS2_TDEP_H
-
-#include "gdbarch.h"
-
-/* Nios II ISA specific encodings and macros.  */
-#include "opcode/nios2.h"
-
-/* Registers.  */
-#define NIOS2_Z_REGNUM 0     /* Zero */
-#define NIOS2_R2_REGNUM 2    /* used for return value */
-#define NIOS2_R3_REGNUM 3    /* used for return value */
-/* Used for hidden zero argument to store ptr to struct return value.  */
-#define NIOS2_R4_REGNUM 4
-#define NIOS2_R7_REGNUM 7
-#define NIOS2_GP_REGNUM 26  /* Global Pointer */
-#define NIOS2_SP_REGNUM 27  /* Stack Pointer */
-#define NIOS2_FP_REGNUM 28  /* Frame Pointer */
-#define NIOS2_EA_REGNUM 29  /* Exception address */
-#define NIOS2_BA_REGNUM 30  /* Breakpoint return address */
-#define NIOS2_RA_REGNUM 31  /* Return address */
-#define NIOS2_PC_REGNUM 32
-
-/* Control registers.  */
-#define NIOS2_STATUS_REGNUM 33
-#define NIOS2_ESTATUS_REGNUM 34
-#define NIOS2_BSTATUS_REGNUM 35
-#define NIOS2_IENABLE_REGNUM 36
-#define NIOS2_IPENDING_REGNUM 37
-#define NIOS2_CPUID_REGNUM 38
-#define NIOS2_EXCEPTION_REGNUM 40
-#define NIOS2_PTEADDR_REGNUM 41
-#define NIOS2_TLBACC_REGNUM 42
-#define NIOS2_TLBMISC_REGNUM 43
-#define NIOS2_ECCINJ_REGNUM 44
-#define NIOS2_BADADDR_REGNUM 45
-#define NIOS2_CONFIG_REGNUM 46
-#define NIOS2_MPUBASE_REGNUM 47
-#define NIOS2_MPUACC_REGNUM 48
-
-/* R4-R7 are used for argument passing.  */
-#define NIOS2_FIRST_ARGREG NIOS2_R4_REGNUM
-#define NIOS2_LAST_ARGREG NIOS2_R7_REGNUM
-
-/* Number of all registers.  */
-#define NIOS2_NUM_REGS 49
-
-/* Size of an instruction, in bytes.  */
-#define NIOS2_OPCODE_SIZE 4
-#define NIOS2_CDX_OPCODE_SIZE 2
-
-/* Target-dependent structure in gdbarch.  */
-struct nios2_gdbarch_tdep : gdbarch_tdep_base
-{
-  /* Assumes FRAME is stopped at a syscall (trap) instruction; returns
-     the expected next PC.  */
-  CORE_ADDR (*syscall_next_pc) (const frame_info_ptr &frame,
-				const struct nios2_opcode *op) = nullptr;
-
-  /* Returns true if PC points to a kernel helper function.  */
-  bool (*is_kernel_helper) (CORE_ADDR pc) = nullptr;
-
-  /* Offset to PC value in jump buffer.
-     If this is negative, longjmp support will be disabled.  */
-  int jb_pc = 0;
-};
-
-extern const struct target_desc *tdesc_nios2_linux;
-extern const struct target_desc *tdesc_nios2;
-
-#endif /* NIOS2_TDEP_H */
diff --git a/gdb/regformats/nios2-linux.dat b/gdb/regformats/nios2-linux.dat
deleted file mode 100644
index ecfca72..0000000
--- a/gdb/regformats/nios2-linux.dat
+++ /dev/null
@@ -1,55 +0,0 @@
-# THIS FILE IS GENERATED.  -*- buffer-read-only: t -*- vi :set ro:
-# Generated from: nios2-linux.xml
-name:nios2_linux
-xmltarget:nios2-linux.xml
-expedite:sp,pc
-osabi:GNU/Linux
-32:zero
-32:at
-32:r2
-32:r3
-32:r4
-32:r5
-32:r6
-32:r7
-32:r8
-32:r9
-32:r10
-32:r11
-32:r12
-32:r13
-32:r14
-32:r15
-32:r16
-32:r17
-32:r18
-32:r19
-32:r20
-32:r21
-32:r22
-32:r23
-32:et
-32:bt
-32:gp
-32:sp
-32:fp
-32:ea
-32:sstatus
-32:ra
-32:pc
-32:status
-32:estatus
-32:bstatus
-32:ienable
-32:ipending
-32:cpuid
-32:ctl6
-32:exception
-32:pteaddr
-32:tlbacc
-32:tlbmisc
-32:eccinj
-32:badaddr
-32:config
-32:mpubase
-32:mpuacc
diff --git a/gdb/testsuite/gdb.base/sigaltstack.exp b/gdb/testsuite/gdb.base/sigaltstack.exp
index ae1634f..fea4e7c 100644
--- a/gdb/testsuite/gdb.base/sigaltstack.exp
+++ b/gdb/testsuite/gdb.base/sigaltstack.exp
@@ -73,7 +73,6 @@ proc finish_test { pattern msg } {
 	    # don't gracefully fall back to single-stepping.
 	    setup_kfail gdb/8841 "i?86-*-linux*"
 	    setup_kfail gdb/8841 "*-*-openbsd*"
-	    setup_kfail gdb/8841 "nios2-*-linux*"
 	    fail "$msg (could not set breakpoint)"
 	}
 	-re "$pattern.*${gdb_prompt} $" {
diff --git a/gdb/testsuite/gdb.base/sigbpt.exp b/gdb/testsuite/gdb.base/sigbpt.exp
index 6f4616e..6808db2 100644
--- a/gdb/testsuite/gdb.base/sigbpt.exp
+++ b/gdb/testsuite/gdb.base/sigbpt.exp
@@ -158,7 +158,6 @@ proc stepi_out { name args } {
 	    fail "$test (could not insert single-step breakpoint)"
 	}
 	-re "Cannot insert breakpoint.*Cannot access memory.*$gdb_prompt $" {
-	    setup_kfail gdb/8841 "nios2*-*-linux*"
 	    fail "$test (could not insert single-step breakpoint)"
 	}
 	-re "keeper.*$gdb_prompt $" {
diff --git a/gdb/testsuite/gdb.base/siginfo.exp b/gdb/testsuite/gdb.base/siginfo.exp
index 4914e3d..d703250 100644
--- a/gdb/testsuite/gdb.base/siginfo.exp
+++ b/gdb/testsuite/gdb.base/siginfo.exp
@@ -61,7 +61,6 @@ gdb_test_multiple "step" "${test}" {
 	fail "$test (could not insert single-step breakpoint)"
     }
     -re "Cannot insert breakpoint.*Cannot access memory.*$gdb_prompt $" {
-        setup_kfail gdb/8841 "nios2*-*-linux*"
 	fail "$test (could not insert single-step breakpoint)"
     }
     -re "done = 1;.*${gdb_prompt} $" {
diff --git a/gdb/testsuite/gdb.base/sigstep.exp b/gdb/testsuite/gdb.base/sigstep.exp
index 4437bf6..315d89d 100644
--- a/gdb/testsuite/gdb.base/sigstep.exp
+++ b/gdb/testsuite/gdb.base/sigstep.exp
@@ -117,7 +117,6 @@ proc advance { enter_cmd in_handler_prefix in_handler exit_cmd } {
 		fail "$test (could not insert single-step breakpoint)"
 	    }
 	    -re "Cannot insert breakpoint.*Cannot access memory.*$gdb_prompt $" {
-		setup_kfail gdb/8841 "nios2*-*-linux*"
 		fail "$test (could not insert single-step breakpoint)"
 	    }
 	    -re "done = 1;.*${gdb_prompt} $" {
@@ -214,7 +213,6 @@ proc advancei { cmd } {
 		# don't gracefully fall back to single-stepping.
 		setup_kfail gdb/8841 "i?86-*-linux*"
 		setup_kfail gdb/8841 "*-*-openbsd*"
-		setup_kfail gdb/8841 "nios2-*-linux*"
 		fail "$test (could not set breakpoint)"
 		return
 	    }
diff --git a/gdb/testsuite/gdb.xml/tdesc-regs.exp b/gdb/testsuite/gdb.xml/tdesc-regs.exp
index 344e387..639c8d5 100644
--- a/gdb/testsuite/gdb.xml/tdesc-regs.exp
+++ b/gdb/testsuite/gdb.xml/tdesc-regs.exp
@@ -45,9 +45,6 @@ switch -glob -- [istarget] {
     "nds32*-*-*" {
 	set core-regs {nds32-core.xml}
     }
-    "nios2-*-*" {
-	set core-regs {nios2-cpu.xml}
-    }
     "or1k-*-*" {
 	set core-regs {or1k-core.xml}
     }
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 127ab27..7ee2043 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -3671,7 +3671,7 @@ proc can_hardware_single_step {} {
 
     if { [istarget "arm*-*-*"] || [istarget "mips*-*-*"]
 	 || [istarget "tic6x-*-*"] || [istarget "sparc*-*-linux*"]
-	 || [istarget "nios2-*-*"] || [istarget "riscv*-*-linux*"] } {
+	 || [istarget "riscv*-*-linux*"] } {
 	return 0
     }
 
diff --git a/gdbserver/Makefile.in b/gdbserver/Makefile.in
index f555ff4..365dcf2 100644
--- a/gdbserver/Makefile.in
+++ b/gdbserver/Makefile.in
@@ -199,7 +199,6 @@ SFILES = \
 	$(srcdir)/linux-low.cc \
 	$(srcdir)/linux-m68k-low.cc \
 	$(srcdir)/linux-mips-low.cc \
-	$(srcdir)/linux-nios2-low.cc \
 	$(srcdir)/linux-or1k-low.cc \
 	$(srcdir)/linux-ppc-low.cc \
 	$(srcdir)/linux-riscv-low.cc \
diff --git a/gdbserver/configure.srv b/gdbserver/configure.srv
index 9535913..ffc8494 100644
--- a/gdbserver/configure.srv
+++ b/gdbserver/configure.srv
@@ -188,14 +188,6 @@ case "${gdbserver_host}" in
 			srv_linux_usrregs=yes
 			srv_linux_thread_db=yes
 			;;
-  nios2*-*-linux*)	srv_regobj="nios2-linux.o"
-			srv_tgtobj="$srv_linux_obj linux-nios2-low.o"
-			srv_xmlfiles="nios2-linux.xml"
-			srv_xmlfiles="${srv_xmlfiles} nios2-cpu.xml"
-			srv_linux_regsets=yes
-			srv_linux_usrregs=yes
-			srv_linux_thread_db=yes
-			;;
   or1k*-*-linux*)	srv_regobj="or1k-linux.o"
 			srv_tgtobj="$srv_linux_obj linux-or1k-low.o"
 			srv_xmlfiles="or1k-linux.xml"
diff --git a/gdbserver/linux-nios2-low.cc b/gdbserver/linux-nios2-low.cc
deleted file mode 100644
index c37bb5a5..0000000
--- a/gdbserver/linux-nios2-low.cc
+++ /dev/null
@@ -1,289 +0,0 @@
-/* GNU/Linux/Nios II specific low level interface, for the remote server for
-   GDB.
-   Copyright (C) 2008-2024 Free Software Foundation, Inc.
-
-   Contributed by Mentor Graphics, Inc.
-
-   This file is part of GDB.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program 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 a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include "linux-low.h"
-#include "elf/common.h"
-#include "nat/gdb_ptrace.h"
-#include <endian.h>
-#include "gdb_proc_service.h"
-#include <asm/ptrace.h>
-
-#ifndef PTRACE_GET_THREAD_AREA
-#define PTRACE_GET_THREAD_AREA 25
-#endif
-
-/* Linux target op definitions for the NIOS II architecture.  */
-
-class nios2_target : public linux_process_target
-{
-public:
-
-  const regs_info *get_regs_info () override;
-
-  const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
-
-protected:
-
-  void low_arch_setup () override;
-
-  bool low_cannot_fetch_register (int regno) override;
-
-  bool low_cannot_store_register (int regno) override;
-
-  bool low_supports_breakpoints () override;
-
-  CORE_ADDR low_get_pc (regcache *regcache) override;
-
-  void low_set_pc (regcache *regcache, CORE_ADDR newpc) override;
-
-  bool low_breakpoint_at (CORE_ADDR pc) override;
-};
-
-/* The singleton target ops object.  */
-
-static nios2_target the_nios2_target;
-
-bool
-nios2_target::low_supports_breakpoints ()
-{
-  return true;
-}
-
-CORE_ADDR
-nios2_target::low_get_pc (regcache *regcache)
-{
-  return linux_get_pc_32bit (regcache);
-}
-
-void
-nios2_target::low_set_pc (regcache *regcache, CORE_ADDR pc)
-{
-  linux_set_pc_32bit (regcache, pc);
-}
-
-/* The following definition must agree with the number of registers
-   defined in "struct user_regs" in GLIBC
-   (sysdeps/unix/sysv/linux/nios2/sys/user.h), and also with
-   NIOS2_NUM_REGS in GDB proper.  */
-
-#define nios2_num_regs 49
-
-/* Defined in auto-generated file nios2-linux.c.  */
-
-void init_registers_nios2_linux (void);
-extern const struct target_desc *tdesc_nios2_linux;
-
-/* This union is used to convert between int and byte buffer
-   representations of register contents.  */
-
-union nios2_register
-{
-  unsigned char buf[4];
-  int reg32;
-};
-
-/* Return the ptrace ``address'' of register REGNO. */
-
-static int nios2_regmap[] = {
-  -1,  1,  2,  3,  4,  5,  6,  7,
-  8,  9,  10, 11, 12, 13, 14, 15,
-  16, 17, 18, 19, 20, 21, 22, 23,
-  24, 25, 26, 27, 28, 29, 30, 31,
-  32, 33, 34, 35, 36, 37, 38, 39,
-  40, 41, 42, 43, 44, 45, 46, 47,
-  48,
-  0
-};
-
-/* Implement the low_arch_setup linux target ops method.  */
-
-void
-nios2_target::low_arch_setup ()
-{
-  current_process ()->tdesc = tdesc_nios2_linux;
-}
-
-/* Implement the low_cannot_fetch_register linux target ops method.  */
-
-bool
-nios2_target::low_cannot_fetch_register (int regno)
-{
-  return (nios2_regmap[regno] == -1);
-}
-
-/* Implement the low_cannot_store_register linux target ops method.  */
-
-bool
-nios2_target::low_cannot_store_register (int regno)
-{
-  return (nios2_regmap[regno] == -1);
-}
-
-/* Breakpoint support.  Also see comments on nios2_breakpoint_from_pc
-   in nios2-tdep.c.  */
-
-#if defined(__nios2_arch__) && __nios2_arch__ == 2
-#define NIOS2_BREAKPOINT 0xb7fd0020
-#define CDX_BREAKPOINT 0xd7c9
-#else
-#define NIOS2_BREAKPOINT 0x003b6ffa
-#endif
-
-/* We only register the 4-byte breakpoint, even on R2 targets which also
-   support 2-byte breakpoints.  Since there is no supports_z_point_type
-   function provided, gdbserver never inserts software breakpoints itself
-   and instead relies on GDB to insert the breakpoint of the correct length
-   via a memory write.  */
-static const unsigned int nios2_breakpoint = NIOS2_BREAKPOINT;
-#define nios2_breakpoint_len 4
-
-/* Implementation of target ops method "sw_breakpoint_from_kind".  */
-
-const gdb_byte *
-nios2_target::sw_breakpoint_from_kind (int kind, int *size)
-{
-  *size = nios2_breakpoint_len;
-  return (const gdb_byte *) &nios2_breakpoint;
-}
-
-/* Implement the low_breakpoint_at linux target ops method.  */
-
-bool
-nios2_target::low_breakpoint_at (CORE_ADDR where)
-{
-  unsigned int insn;
-
-  /* For R2, first check for the 2-byte CDX trap.n breakpoint encoding.  */
-#if defined(__nios2_arch__) && __nios2_arch__ == 2
-  read_memory (where, (unsigned char *) &insn, 2);
-  if (insn == CDX_BREAKPOINT)
-    return true;
-#endif
-
-  read_memory (where, (unsigned char *) &insn, 4);
-  if (insn == nios2_breakpoint)
-    return true;
-  return false;
-}
-
-/* Fetch the thread-local storage pointer for libthread_db.  */
-
-ps_err_e
-ps_get_thread_area (struct ps_prochandle *ph,
-		    lwpid_t lwpid, int idx, void **base)
-{
-  if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) != 0)
-    return PS_ERR;
-
-  /* IDX is the bias from the thread pointer to the beginning of the
-     thread descriptor.  It has to be subtracted due to implementation
-     quirks in libthread_db.  */
-  *base = (void *) ((char *) *base - idx);
-
-  return PS_OK;
-}
-
-/* Helper functions to collect/supply a single register REGNO.  */
-
-static void
-nios2_collect_register (struct regcache *regcache, int regno,
-			union nios2_register *reg)
-{
-  union nios2_register tmp_reg;
-
-  collect_register (regcache, regno, &tmp_reg.reg32);
-  reg->reg32 = tmp_reg.reg32;
-}
-
-static void
-nios2_supply_register (struct regcache *regcache, int regno,
-		       const union nios2_register *reg)
-{
-  supply_register (regcache, regno, reg->buf);
-}
-
-/* We have only a single register set on Nios II.  */
-
-static void
-nios2_fill_gregset (struct regcache *regcache, void *buf)
-{
-  union nios2_register *regset = (union nios2_register *) buf;
-  int i;
-
-  for (i = 1; i < nios2_num_regs; i++)
-    nios2_collect_register (regcache, i, regset + i);
-}
-
-static void
-nios2_store_gregset (struct regcache *regcache, const void *buf)
-{
-  const union nios2_register *regset = (union nios2_register *) buf;
-  int i;
-
-  for (i = 0; i < nios2_num_regs; i++)
-    nios2_supply_register (regcache, i, regset + i);
-}
-
-static struct regset_info nios2_regsets[] =
-{
-  { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_PRSTATUS,
-    nios2_num_regs * 4, GENERAL_REGS,
-    nios2_fill_gregset, nios2_store_gregset },
-  NULL_REGSET
-};
-
-static struct regsets_info nios2_regsets_info =
-  {
-    nios2_regsets, /* regsets */
-    0, /* num_regsets */
-    NULL, /* disabled_regsets */
-  };
-
-static struct usrregs_info nios2_usrregs_info =
-  {
-    nios2_num_regs,
-    nios2_regmap,
-  };
-
-static struct regs_info myregs_info =
-  {
-    NULL, /* regset_bitmap */
-    &nios2_usrregs_info,
-    &nios2_regsets_info
-  };
-
-const regs_info *
-nios2_target::get_regs_info ()
-{
-  return &myregs_info;
-}
-
-/* The linux target ops object.  */
-
-linux_process_target *the_linux_target = &the_nios2_target;
-
-void
-initialize_low_arch (void)
-{
-  init_registers_nios2_linux ();
-
-  initialize_regsets_info (&nios2_regsets_info);
-}