Convert amd64-linux target descriptions

This patch changes amd64-linux target descriptions so that they can be
dynamically generated in both GDB and GDBserver.

gdb/gdbserver:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* Makefile.in (arch-amd64.o): New rule.
	* configure.srv: Append arch-amd64.o.
	* linux-amd64-ipa.c: Include common/x86-xstate.h.
	(get_ipa_tdesc): Call amd64_linux_read_description.
	(initialize_low_tracepoint): Don't call init_registers_x32_XXX
	and init_registers_amd64_XXX.
	* linux-x86-low.c (x86_linux_read_description): Call
	amd64_linux_read_description.
	(x86_get_ipa_tdesc_idx): Call amd64_get_ipa_tdesc_idx.
	(initialize_low_arch): Don't call init_registers_x32_XXX and
	init_registers_amd64_XXX.
	* linux-x86-tdesc-selftest.c: Declare init_registers_amd64_XXX
	and tdesc_amd64_XXX.
	[__x86_64__] (amd64_tdesc_test): New function.
	(initialize_low_tdesc) [__x86_64__]: Call init_registers_x32_XXX
	and init_registers_amd64_XXX.
	* linux-x86-tdesc.c: Include arch/amd64.h.
	(xcr0_to_tdesc_idx): New function.
	(i386_linux_read_description): New function.
	(amd64_get_ipa_tdesc_idx): New function.
	* linux-x86-tdesc.h (amd64_get_ipa_tdesc_idx): Declare.
	(amd64_get_ipa_tdesc): Declare.

gdb:

2017-09-05  Yao Qi  <yao.qi@linaro.org>

	* amd64-linux-tdep.c: Include arch/amd64.h.  Don't include
	features/i386/*.c.
	(amd64_linux_read_description): Call
	amd64_create_target_description.
	* arch/amd64.c: New file.
	* arch/amd64.h: New file.
	* configure.tgt (x86_64-*-linux*): Append amd64.o.
	* Makefile.in (ALL_64_TARGET_OBS): Append amd64.o.

14 files changed, 375 insertions, 210 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9ac02daa7e8..91c5b20f008 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,16 @@
 2017-09-05  Yao Qi  <yao.qi@linaro.org>
 
+	* amd64-linux-tdep.c: Include arch/amd64.h.  Don't include
+	features/i386/*.c.
+	(amd64_linux_read_description): Call
+	amd64_create_target_description.
+	* arch/amd64.c: New file.
+	* arch/amd64.h: New file.
+	* configure.tgt (x86_64-*-linux*): Append amd64.o.
+	* Makefile.in (ALL_64_TARGET_OBS): Append amd64.o.
+
+2017-09-05  Yao Qi  <yao.qi@linaro.org>
+
 	* amd64-linux-tdep.c: Don't include amd64-XXX-linux and
 	x32-XXX-linux.c.  Include 64bit-XX.c and x32-XX.c.
 	(amd64_linux_read_description): Create target descriptions.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 2caa67437d5..69e80fa138c 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -763,6 +763,7 @@ ALL_64_TARGET_OBS = \
 	alpha-nbsd-tdep.o \
 	alpha-obsd-tdep.o \
 	alpha-tdep.o \
+	amd64.o \
 	amd64-darwin-tdep.o \
 	amd64-dicos-tdep.o \
 	amd64-fbsd-tdep.o \
diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
index 7afa0124802..7fbd328cdd9 100644
--- a/gdb/amd64-linux-tdep.c
+++ b/gdb/amd64-linux-tdep.c
@@ -39,19 +39,9 @@
 #include "solib-svr4.h"
 #include "xml-syscall.h"
 #include "glibc-tdep.h"
+#include "arch/amd64.h"
 #include "target-descriptions.h"
 
-#include "features/i386/64bit-avx.c"
-#include "features/i386/64bit-avx512.c"
-#include "features/i386/64bit-core.c"
-#include "features/i386/64bit-linux.c"
-#include "features/i386/64bit-mpx.c"
-#include "features/i386/64bit-pkeys.c"
-#include "features/i386/64bit-segments.c"
-#include "features/i386/64bit-sse.c"
-
-#include "features/i386/x32-core.c"
-
 /* The syscall's XML filename for i386.  */
 #define XML_SYSCALL_FILENAME_AMD64 "syscalls/amd64-linux.xml"
 
@@ -1599,37 +1589,7 @@ amd64_linux_read_description (uint64_t xcr0_features_bit, bool is_x32)
     }
 
   if (*tdesc == NULL)
-    {
-      *tdesc = allocate_target_description ();
-
-      set_tdesc_architecture (*tdesc,
-			      is_x32 ? "i386:x64-32" : "i386:x86-64");
-
-      set_tdesc_osabi (*tdesc, osabi_from_tdesc_string ("GNU/Linux"));
-
-      long regnum = 0;
-
-      if (is_x32)
-	regnum = create_feature_i386_x32_core (*tdesc, regnum);
-      else
-	regnum = create_feature_i386_64bit_core (*tdesc, regnum);
-
-      regnum = create_feature_i386_64bit_sse (*tdesc, regnum);
-      regnum = create_feature_i386_64bit_linux (*tdesc, regnum);
-      regnum = create_feature_i386_64bit_segments (*tdesc, regnum);
-
-      if (xcr0_features_bit & X86_XSTATE_AVX)
-	regnum = create_feature_i386_64bit_avx (*tdesc, regnum);
-
-      if ((xcr0_features_bit & X86_XSTATE_MPX) && !is_x32)
-	regnum = create_feature_i386_64bit_mpx (*tdesc, regnum);
-
-      if (xcr0_features_bit & X86_XSTATE_AVX512)
-	regnum = create_feature_i386_64bit_avx512 (*tdesc, regnum);
-
-      if ((xcr0_features_bit & X86_XSTATE_PKRU) && !is_x32)
-	regnum = create_feature_i386_64bit_pkeys (*tdesc, regnum);
-    }
+    *tdesc = amd64_create_target_description (xcr0_features_bit, is_x32);
 
   return *tdesc;
 }
diff --git a/gdb/arch/amd64.c b/gdb/arch/amd64.c
new file mode 100644
index 00000000000..626733d6dbd
--- /dev/null
+++ b/gdb/arch/amd64.c
@@ -0,0 +1,71 @@
+/* Copyright (C) 2017 Free Software Foundation, 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 "amd64.h"
+#include "x86-xstate.h"
+#include <stdlib.h>
+
+#include "../features/i386/64bit-avx.c"
+#include "../features/i386/64bit-avx512.c"
+#include "../features/i386/64bit-core.c"
+#include "../features/i386/64bit-linux.c"
+#include "../features/i386/64bit-mpx.c"
+#include "../features/i386/64bit-pkeys.c"
+#include "../features/i386/64bit-segments.c"
+#include "../features/i386/64bit-sse.c"
+
+#include "../features/i386/x32-core.c"
+
+/* Create amd64 target descriptions according to XCR0.  If IS_X32 is
+   true, create the x32 ones.  */
+
+target_desc *
+amd64_create_target_description (uint64_t xcr0, bool is_x32)
+{
+  target_desc *tdesc = allocate_target_description ();
+
+#ifndef IN_PROCESS_AGENT
+  set_tdesc_architecture (tdesc, is_x32 ? "i386:x64-32" : "i386:x86-64");
+
+  set_tdesc_osabi (tdesc, "GNU/Linux");
+#endif
+
+  long regnum = 0;
+
+  if (is_x32)
+    regnum = create_feature_i386_x32_core (tdesc, regnum);
+  else
+    regnum = create_feature_i386_64bit_core (tdesc, regnum);
+
+  regnum = create_feature_i386_64bit_sse (tdesc, regnum);
+  regnum = create_feature_i386_64bit_linux (tdesc, regnum);
+  regnum = create_feature_i386_64bit_segments (tdesc, regnum);
+
+  if (xcr0 & X86_XSTATE_AVX)
+    regnum = create_feature_i386_64bit_avx (tdesc, regnum);
+
+  if ((xcr0 & X86_XSTATE_MPX) && !is_x32)
+    regnum = create_feature_i386_64bit_mpx (tdesc, regnum);
+
+  if (xcr0 & X86_XSTATE_AVX512)
+    regnum = create_feature_i386_64bit_avx512 (tdesc, regnum);
+
+  if ((xcr0 & X86_XSTATE_PKRU) && !is_x32)
+    regnum = create_feature_i386_64bit_pkeys (tdesc, regnum);
+
+  return tdesc;
+}
diff --git a/gdb/arch/amd64.h b/gdb/arch/amd64.h
new file mode 100644
index 00000000000..0821a7c0f43
--- /dev/null
+++ b/gdb/arch/amd64.h
@@ -0,0 +1,21 @@
+/* Copyright (C) 2017 Free Software Foundation, 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 "tdesc.h"
+#include <stdint.h>
+
+target_desc *amd64_create_target_description (uint64_t xcr0, bool is_x32);
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 1f263515fd4..402d6babfdc 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -678,7 +678,7 @@ x86_64-*-elf*)
 	;;
 x86_64-*-linux*)
 	# Target: GNU/Linux x86-64
-	gdb_target_obs="amd64-tdep.o amd64-linux-tdep.o i386-tdep.o \
+	gdb_target_obs="amd64-tdep.o amd64-linux-tdep.o amd64.o i386-tdep.o \
 			i387-tdep.o i386.o i386-linux-tdep.o glibc-tdep.o \
 			solib-svr4.o symfile-mem.o linux-tdep.o linux-record.o"
 	build_gdbserver=yes
diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 30b4fec8e2c..0efb7e129fa 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,5 +1,30 @@
 2017-09-05  Yao Qi  <yao.qi@linaro.org>
 
+	* Makefile.in (arch-amd64.o): New rule.
+	* configure.srv: Append arch-amd64.o.
+	* linux-amd64-ipa.c: Include common/x86-xstate.h.
+	(get_ipa_tdesc): Call amd64_linux_read_description.
+	(initialize_low_tracepoint): Don't call init_registers_x32_XXX
+	and init_registers_amd64_XXX.
+	* linux-x86-low.c (x86_linux_read_description): Call
+	amd64_linux_read_description.
+	(x86_get_ipa_tdesc_idx): Call amd64_get_ipa_tdesc_idx.
+	(initialize_low_arch): Don't call init_registers_x32_XXX and
+	init_registers_amd64_XXX.
+	* linux-x86-tdesc-selftest.c: Declare init_registers_amd64_XXX
+	and tdesc_amd64_XXX.
+	[__x86_64__] (amd64_tdesc_test): New function.
+	(initialize_low_tdesc) [__x86_64__]: Call init_registers_x32_XXX
+	and init_registers_amd64_XXX.
+	* linux-x86-tdesc.c: Include arch/amd64.h.
+	(xcr0_to_tdesc_idx): New function.
+	(i386_linux_read_description): New function.
+	(amd64_get_ipa_tdesc_idx): New function.
+	* linux-x86-tdesc.h (amd64_get_ipa_tdesc_idx): Declare.
+	(amd64_get_ipa_tdesc): Declare.
+
+2017-09-05  Yao Qi  <yao.qi@linaro.org>
+
 	* configure.srv (srv_i386_linux_xmlfiles): Remove
 	i386/i386-XXX-linux.xml from it.
 
diff --git a/gdb/gdbserver/Makefile.in b/gdb/gdbserver/Makefile.in
index b552b698147..1bbe5156295 100644
--- a/gdb/gdbserver/Makefile.in
+++ b/gdb/gdbserver/Makefile.in
@@ -532,6 +532,10 @@ arch-i386.o: ../arch/i386.c
 	$(COMPILE) $<
 	$(POSTCOMPILE)
 
+arch-amd64.o: ../arch/amd64.c
+	$(COMPILE) $<
+	$(POSTCOMPILE)
+
 # Rules for objects that go in the in-process agent.
 
 %-ipa.o: %-generated.c
diff --git a/gdb/gdbserver/configure.srv b/gdb/gdbserver/configure.srv
index 946119c0cc9..95649f4b850 100644
--- a/gdb/gdbserver/configure.srv
+++ b/gdb/gdbserver/configure.srv
@@ -365,7 +365,7 @@ case "${target}" in
 			;;
   x86_64-*-linux*)	srv_regobj="$srv_amd64_linux_regobj $srv_i386_linux_regobj"
 			srv_tgtobj="$srv_linux_obj linux-x86-low.o x86-low.o x86-dregs.o i387-fp.o"
-			srv_tgtobj="${srv_tgtobj} arch-i386.o"
+			srv_tgtobj="${srv_tgtobj} arch-i386.o arch-amd64.o"
 			srv_tgtobj="${srv_tgtobj} linux-x86-tdesc.o"
 			srv_tgtobj="${srv_tgtobj} linux-btrace.o x86-linux.o"
 			srv_tgtobj="${srv_tgtobj} x86-linux-dregs.o"
@@ -381,6 +381,7 @@ case "${target}" in
 			    ipa_obj="${ipa_amd64_linux_regobj}"
 			fi
 			ipa_obj="${ipa_obj} linux-amd64-ipa.o linux-x86-tdesc-ipa.o"
+			ipa_obj="${ipa_obj} amd64-ipa.o"
 			;;
   x86_64-*-mingw*)	srv_regobj="$srv_amd64_regobj"
 			srv_tgtobj="x86-low.o x86-dregs.o i387-fp.o win32-low.o win32-i386-low.o"
diff --git a/gdb/gdbserver/linux-amd64-ipa.c b/gdb/gdbserver/linux-amd64-ipa.c
index 683339b2013..85d0d453746 100644
--- a/gdb/gdbserver/linux-amd64-ipa.c
+++ b/gdb/gdbserver/linux-amd64-ipa.c
@@ -22,6 +22,7 @@
 #include <sys/mman.h>
 #include "tracepoint.h"
 #include "linux-x86-tdesc.h"
+#include "common/x86-xstate.h"
 
 /* Defined in auto-generated file amd64-linux.c.  */
 void init_registers_amd64_linux (void);
@@ -174,38 +175,37 @@ supply_static_tracepoint_registers (struct regcache *regcache,
 const struct target_desc *
 get_ipa_tdesc (int idx)
 {
+  if (idx >= X86_TDESC_LAST)
+    {
+      internal_error (__FILE__, __LINE__,
+		      "unknown ipa tdesc index: %d", idx);
+    }
+
 #if defined __ILP32__
   switch (idx)
     {
     case X86_TDESC_SSE:
-      return tdesc_x32_linux;
+      return amd64_linux_read_description (X86_XSTATE_SSE_MASK, true);
     case X86_TDESC_AVX:
-      return tdesc_x32_avx_linux;
+      return amd64_linux_read_description (X86_XSTATE_AVX_MASK, true);
     case X86_TDESC_AVX_AVX512:
-      return tdesc_x32_avx_avx512_linux;
+      return amd64_linux_read_description (X86_XSTATE_AVX_AVX512_MASK, true);
     default:
       break;
     }
 #else
-  switch (idx)
-    {
-    case X86_TDESC_SSE:
-      return tdesc_amd64_linux;
-    case X86_TDESC_AVX:
-      return tdesc_amd64_avx_linux;
-    case X86_TDESC_MPX:
-      return tdesc_amd64_mpx_linux;
-    case X86_TDESC_AVX_MPX:
-      return tdesc_amd64_avx_mpx_linux;
-    case X86_TDESC_AVX_MPX_AVX512_PKU:
-      return tdesc_amd64_avx_mpx_avx512_pku_linux;
-    case X86_TDESC_AVX_AVX512:
-      return tdesc_amd64_avx_avx512_linux;
-    default:
-      internal_error (__FILE__, __LINE__,
-		      "unknown ipa tdesc index: %d", idx);
-      return tdesc_amd64_linux;
-    }
+  /* Map the tdesc index to xcr0 mask.  */
+  uint64_t idx2mask[X86_TDESC_LAST] = {
+    X86_XSTATE_X87_MASK,
+    X86_XSTATE_SSE_MASK,
+    X86_XSTATE_AVX_MASK,
+    X86_XSTATE_MPX_MASK,
+    X86_XSTATE_AVX_MPX_MASK,
+    X86_XSTATE_AVX_AVX512_MASK,
+    X86_XSTATE_AVX_MPX_AVX512_PKU_MASK,
+  };
+
+  return amd64_linux_read_description (idx2mask[idx], false);
 #endif
 
   internal_error (__FILE__, __LINE__,
@@ -276,16 +276,4 @@ alloc_jump_pad_buffer (size_t size)
 void
 initialize_low_tracepoint (void)
 {
-#if defined __ILP32__
-  init_registers_x32_linux ();
-  init_registers_x32_avx_linux ();
-  init_registers_x32_avx_avx512_linux ();
-#else
-  init_registers_amd64_linux ();
-  init_registers_amd64_avx_linux ();
-  init_registers_amd64_mpx_linux ();
-  init_registers_amd64_avx_mpx_linux ();
-  init_registers_amd64_avx_avx512_linux ();
-  init_registers_amd64_avx_mpx_avx512_pku_linux ();
-#endif
 }
diff --git a/gdb/gdbserver/linux-x86-low.c b/gdb/gdbserver/linux-x86-low.c
index 54be82f870f..f09871ac36f 100644
--- a/gdb/gdbserver/linux-x86-low.c
+++ b/gdb/gdbserver/linux-x86-low.c
@@ -817,58 +817,17 @@ x86_linux_read_description (void)
   if (machine == EM_X86_64)
     {
 #ifdef __x86_64__
-      if (is_elf64)
-	{
-	  if (xcr0_features)
-	    {
-	      switch (xcr0 & X86_XSTATE_ALL_MASK)
-	        {
-		case X86_XSTATE_AVX_MPX_AVX512_PKU_MASK:
-		  return tdesc_amd64_avx_mpx_avx512_pku_linux;
-
-		case X86_XSTATE_AVX_AVX512_MASK:
-		  return tdesc_amd64_avx_avx512_linux;
-
-		case X86_XSTATE_AVX_MPX_MASK:
-		  return tdesc_amd64_avx_mpx_linux;
-
-		case X86_XSTATE_MPX_MASK:
-		  return tdesc_amd64_mpx_linux;
-
-		case X86_XSTATE_AVX_MASK:
-		  return tdesc_amd64_avx_linux;
+      const target_desc *tdesc = NULL;
 
-		default:
-		  return tdesc_amd64_linux;
-		}
-	    }
-	  else
-	    return tdesc_amd64_linux;
-	}
-      else
+      if (xcr0_features)
 	{
-	  if (xcr0_features)
-	    {
-	      switch (xcr0 & X86_XSTATE_ALL_MASK)
-	        {
-		case X86_XSTATE_AVX_MPX_AVX512_PKU_MASK:
-		  /* No x32 MPX and PKU, fall back to avx_avx512.  */
-		  return tdesc_x32_avx_avx512_linux;
-
-		case X86_XSTATE_AVX_AVX512_MASK:
-		  return tdesc_x32_avx_avx512_linux;
-
-		case X86_XSTATE_MPX_MASK: /* No MPX on x32.  */
-		case X86_XSTATE_AVX_MASK:
-		  return tdesc_x32_avx_linux;
-
-		default:
-		  return tdesc_x32_linux;
-		}
-	    }
-	  else
-	    return tdesc_x32_linux;
+	  tdesc = amd64_linux_read_description (xcr0 & X86_XSTATE_ALL_MASK,
+						!is_elf64);
 	}
+
+      if (tdesc == NULL)
+	tdesc = amd64_linux_read_description (X86_XSTATE_SSE_MASK, !is_elf64);
+      return tdesc;
 #endif
     }
   else
@@ -2881,19 +2840,7 @@ x86_get_ipa_tdesc_idx (void)
   const struct target_desc *tdesc = regcache->tdesc;
 
 #ifdef __x86_64__
-  if (tdesc == tdesc_amd64_linux || tdesc == tdesc_amd64_linux_no_xml
-      || tdesc == tdesc_x32_linux)
-    return X86_TDESC_SSE;
-  if (tdesc == tdesc_amd64_avx_linux || tdesc == tdesc_x32_avx_linux)
-    return X86_TDESC_AVX;
-  if (tdesc == tdesc_amd64_mpx_linux)
-    return X86_TDESC_MPX;
-  if (tdesc == tdesc_amd64_avx_mpx_linux)
-    return X86_TDESC_AVX_MPX;
-  if (tdesc == tdesc_amd64_avx_mpx_avx512_pku_linux || tdesc == tdesc_x32_avx_avx512_linux)
-    return X86_TDESC_AVX_MPX_AVX512_PKU;
-  if (tdesc == tdesc_amd64_avx_avx512_linux)
-    return X86_TDESC_AVX_AVX512;
+  return amd64_get_ipa_tdesc_idx (tdesc);
 #endif
 
   if (tdesc == tdesc_i386_linux_no_xml)
@@ -2953,19 +2900,10 @@ initialize_low_arch (void)
 {
   /* Initialize the Linux target descriptions.  */
 #ifdef __x86_64__
-  init_registers_amd64_linux ();
-  init_registers_amd64_avx_linux ();
-  init_registers_amd64_mpx_linux ();
-  init_registers_amd64_avx_mpx_linux ();
-  init_registers_amd64_avx_avx512_linux ();
-  init_registers_amd64_avx_mpx_avx512_pku_linux ();
-
-  init_registers_x32_linux ();
-  init_registers_x32_avx_linux ();
-  init_registers_x32_avx_avx512_linux ();
-
   tdesc_amd64_linux_no_xml = XNEW (struct target_desc);
-  copy_target_description (tdesc_amd64_linux_no_xml, tdesc_amd64_linux);
+  copy_target_description (tdesc_amd64_linux_no_xml,
+			   amd64_linux_read_description (X86_XSTATE_SSE_MASK,
+							 false));
   tdesc_amd64_linux_no_xml->xmltarget = xmltarget_amd64_linux_no_xml;
 #endif
 
diff --git a/gdb/gdbserver/linux-x86-tdesc-selftest.c b/gdb/gdbserver/linux-x86-tdesc-selftest.c
index 558a25be865..aa5a8e9b593 100644
--- a/gdb/gdbserver/linux-x86-tdesc-selftest.c
+++ b/gdb/gdbserver/linux-x86-tdesc-selftest.c
@@ -49,6 +49,46 @@ extern const struct target_desc *tdesc_i386_avx_mpx_avx512_pku_linux;
 void init_registers_i386_mpx_linux (void);
 extern const struct target_desc *tdesc_i386_mpx_linux;
 
+#ifdef __x86_64__
+
+/* Defined in auto-generated file amd64-linux.c.  */
+void init_registers_amd64_linux (void);
+extern const struct target_desc *tdesc_amd64_linux;
+
+/* Defined in auto-generated file amd64-avx-linux.c.  */
+void init_registers_amd64_avx_linux (void);
+extern const struct target_desc *tdesc_amd64_avx_linux;
+
+/* Defined in auto-generated file amd64-avx-avx512-linux.c.  */
+void init_registers_amd64_avx_avx512_linux (void);
+extern const struct target_desc *tdesc_amd64_avx_avx512_linux;
+
+/* Defined in auto-generated file amd64-avx-mpx-avx512-pku-linux.c.  */
+void init_registers_amd64_avx_mpx_avx512_pku_linux (void);
+extern const struct target_desc *tdesc_amd64_avx_mpx_avx512_pku_linux;
+
+/* Defined in auto-generated file amd64-avx-mpx-linux.c.  */
+void init_registers_amd64_avx_mpx_linux (void);
+extern const struct target_desc *tdesc_amd64_avx_mpx_linux;
+
+/* Defined in auto-generated file amd64-mpx-linux.c.  */
+void init_registers_amd64_mpx_linux (void);
+extern const struct target_desc *tdesc_amd64_mpx_linux;
+
+/* Defined in auto-generated file x32-linux.c.  */
+void init_registers_x32_linux (void);
+extern const struct target_desc *tdesc_x32_linux;
+
+/* Defined in auto-generated file x32-avx-linux.c.  */
+void init_registers_x32_avx_linux (void);
+extern const struct target_desc *tdesc_x32_avx_linux;
+
+/* Defined in auto-generated file x32-avx-avx512-linux.c.  */
+void init_registers_x32_avx_avx512_linux (void);
+extern const struct target_desc *tdesc_x32_avx_avx512_linux;
+
+#endif
+
 namespace selftests {
 namespace tdesc {
 static void
@@ -75,6 +115,41 @@ i386_tdesc_test ()
       SELF_CHECK (*tdesc == *elem.tdesc);
     }
 }
+
+#ifdef __x86_64__
+
+static void
+amd64_tdesc_test ()
+{
+  struct
+  {
+    unsigned int mask;
+    const target_desc *tdesc[2];
+  } tdesc_tests[] = {
+    { X86_XSTATE_SSE_MASK, { tdesc_amd64_linux, tdesc_x32_linux } },
+    { X86_XSTATE_AVX_MASK, { tdesc_amd64_avx_linux, tdesc_x32_avx_linux } },
+    { X86_XSTATE_MPX_MASK, { tdesc_amd64_mpx_linux, tdesc_x32_avx_linux } },
+    { X86_XSTATE_AVX_MPX_MASK, { tdesc_amd64_avx_mpx_linux,
+				 tdesc_x32_avx_linux } },
+    { X86_XSTATE_AVX_AVX512_MASK, { tdesc_amd64_avx_avx512_linux,
+      tdesc_x32_avx_avx512_linux } },
+    { X86_XSTATE_AVX_MPX_AVX512_PKU_MASK,
+      { tdesc_amd64_avx_mpx_avx512_pku_linux,  tdesc_x32_avx_avx512_linux } },
+  };
+
+  for (auto &elem : tdesc_tests)
+    {
+      for (int i = 0; i < 2; i++)
+	{
+	  const target_desc *tdesc = amd64_linux_read_description (elem.mask,
+								   i);
+
+	  SELF_CHECK (*tdesc == *elem.tdesc[i]);
+	}
+    }
+}
+
+#endif
 }
 } // namespace selftests
 
@@ -90,4 +165,19 @@ initialize_low_tdesc ()
   init_registers_i386_avx_mpx_avx512_pku_linux ();
 
   selftests::register_test (selftests::tdesc::i386_tdesc_test);
+
+#ifdef __x86_64__
+  init_registers_x32_linux ();
+  init_registers_x32_avx_linux ();
+  init_registers_x32_avx_avx512_linux ();
+
+  init_registers_amd64_linux ();
+  init_registers_amd64_avx_linux ();
+  init_registers_amd64_mpx_linux ();
+  init_registers_amd64_avx_mpx_linux ();
+  init_registers_amd64_avx_avx512_linux ();
+  init_registers_amd64_avx_mpx_avx512_pku_linux ();
+
+  selftests::register_test (selftests::tdesc::amd64_tdesc_test);
+#endif
 }
diff --git a/gdb/gdbserver/linux-x86-tdesc.c b/gdb/gdbserver/linux-x86-tdesc.c
index d1e262c4805..9eb61a7208f 100644
--- a/gdb/gdbserver/linux-x86-tdesc.c
+++ b/gdb/gdbserver/linux-x86-tdesc.c
@@ -22,36 +22,68 @@
 #include "linux-x86-tdesc.h"
 #include "arch/i386.h"
 #include "common/x86-xstate.h"
+#ifdef __x86_64__
+#include "arch/amd64.h"
+#endif
 
-static struct target_desc *i386_tdescs[X86_TDESC_LAST] = { };
+/* Return the right x86_linux_tdesc index for a given XCR0.  Return
+   X86_TDESC_LAST if can't find a match.  */
 
-#if defined __i386__ || !defined IN_PROCESS_AGENT
-
-/* Return the target description according to XCR0.  */
-
-const struct target_desc *
-i386_linux_read_description (uint64_t xcr0)
+static enum x86_linux_tdesc
+xcr0_to_tdesc_idx (uint64_t xcr0, bool is_x32)
 {
-  struct target_desc **tdesc = NULL;
-
   if (xcr0 & X86_XSTATE_PKRU)
-     tdesc = &i386_tdescs[X86_TDESC_AVX_MPX_AVX512_PKU];
+    {
+      if (is_x32)
+	{
+	  /* No x32 MPX and PKU, fall back to avx_avx512.  */
+	  return X86_TDESC_AVX_AVX512;
+	}
+      else
+	return X86_TDESC_AVX_MPX_AVX512_PKU;
+    }
   else if (xcr0 & X86_XSTATE_AVX512)
-    tdesc = &i386_tdescs[X86_TDESC_AVX_AVX512];
+    return X86_TDESC_AVX_AVX512;
   else if ((xcr0 & X86_XSTATE_AVX_MPX_MASK) == X86_XSTATE_AVX_MPX_MASK)
-    tdesc = &i386_tdescs[X86_TDESC_AVX_MPX];
+    {
+      if (is_x32) /* No MPX on x32.  */
+	return X86_TDESC_AVX;
+      else
+	return X86_TDESC_AVX_MPX;
+    }
   else if (xcr0 & X86_XSTATE_MPX)
-    tdesc = &i386_tdescs[X86_TDESC_MPX];
+    {
+      if (is_x32) /* No MPX on x32.  */
+	return X86_TDESC_AVX;
+      else
+	return X86_TDESC_MPX;
+    }
   else if (xcr0 & X86_XSTATE_AVX)
-    tdesc = &i386_tdescs[X86_TDESC_AVX];
+    return X86_TDESC_AVX;
   else if (xcr0 & X86_XSTATE_SSE)
-    tdesc = &i386_tdescs[X86_TDESC_SSE];
+    return X86_TDESC_SSE;
   else if (xcr0 & X86_XSTATE_X87)
-    tdesc = &i386_tdescs[X86_TDESC_MMX];
+    return X86_TDESC_MMX;
+  else
+    return X86_TDESC_LAST;
+}
 
-  if (tdesc == NULL)
+static struct target_desc *i386_tdescs[X86_TDESC_LAST] = { };
+
+#if defined __i386__ || !defined IN_PROCESS_AGENT
+
+/* Return the target description according to XCR0.  */
+
+const struct target_desc *
+i386_linux_read_description (uint64_t xcr0)
+{
+  enum x86_linux_tdesc idx = xcr0_to_tdesc_idx (xcr0, false);
+
+  if (idx == X86_TDESC_LAST)
     return NULL;
 
+  struct target_desc **tdesc = &i386_tdescs[idx];
+
   if (*tdesc == NULL)
     {
       *tdesc = i386_create_target_description (xcr0);
@@ -68,7 +100,44 @@ i386_linux_read_description (uint64_t xcr0)
 }
 #endif
 
+#ifdef __x86_64__
+
+static target_desc *amd64_tdescs[X86_TDESC_LAST] = { };
+static target_desc *x32_tdescs[X86_TDESC_LAST] = { };
+
+const struct target_desc *
+amd64_linux_read_description (uint64_t xcr0, bool is_x32)
+{
+  enum x86_linux_tdesc idx = xcr0_to_tdesc_idx (xcr0, is_x32);
+
+  if (idx == X86_TDESC_LAST)
+    return NULL;
+
+  struct target_desc **tdesc = NULL;
+
+  if (is_x32)
+    tdesc = &x32_tdescs[idx];
+  else
+    tdesc = &amd64_tdescs[idx];
+
+  if (*tdesc == NULL)
+    {
+      *tdesc = amd64_create_target_description (xcr0, is_x32);
+
+      init_target_desc (*tdesc);
+
+#ifndef IN_PROCESS_AGENT
+      static const char *expedite_regs_amd64[] = { "rbp", "rsp", "rip", NULL };
+      (*tdesc)->expedite_regs = expedite_regs_amd64;
+#endif
+    }
+  return *tdesc;
+}
+
+#endif
+
 #ifndef IN_PROCESS_AGENT
+
 int
 i386_get_ipa_tdesc_idx (const struct target_desc *tdesc)
 {
@@ -82,4 +151,23 @@ i386_get_ipa_tdesc_idx (const struct target_desc *tdesc)
   return X86_TDESC_MMX;
 }
 
+#if defined __x86_64__
+int
+amd64_get_ipa_tdesc_idx (const struct target_desc *tdesc)
+{
+  for (int i = 0; i < X86_TDESC_LAST; i++)
+    {
+      if (tdesc == amd64_tdescs[i])
+	return i;
+    }
+  for (int i = 0; i < X86_TDESC_LAST; i++)
+    {
+      if (tdesc == x32_tdescs[i])
+	return i;
+    }
+
+  return X86_TDESC_SSE;
+}
+
+#endif
 #endif
diff --git a/gdb/gdbserver/linux-x86-tdesc.h b/gdb/gdbserver/linux-x86-tdesc.h
index 03bd1f16cf2..a6dc33055b1 100644
--- a/gdb/gdbserver/linux-x86-tdesc.h
+++ b/gdb/gdbserver/linux-x86-tdesc.h
@@ -33,52 +33,19 @@ enum x86_linux_tdesc {
   X86_TDESC_LAST = 7,
 };
 
-#ifdef __x86_64__
-
-#if defined __LP64__  || !defined IN_PROCESS_AGENT
-/* Defined in auto-generated file amd64-linux.c.  */
-void init_registers_amd64_linux (void);
-extern const struct target_desc *tdesc_amd64_linux;
-
-/* Defined in auto-generated file amd64-avx-linux.c.  */
-void init_registers_amd64_avx_linux (void);
-extern const struct target_desc *tdesc_amd64_avx_linux;
-
-/* Defined in auto-generated file amd64-avx-avx512-linux.c.  */
-void init_registers_amd64_avx_avx512_linux (void);
-extern const struct target_desc *tdesc_amd64_avx_avx512_linux;
-
-/* Defined in auto-generated file amd64-avx-mpx-avx512-pku-linux.c.  */
-void init_registers_amd64_avx_mpx_avx512_pku_linux (void);
-extern const struct target_desc *tdesc_amd64_avx_mpx_avx512_pku_linux;
-
-/* Defined in auto-generated file amd64-avx-mpx-linux.c.  */
-void init_registers_amd64_avx_mpx_linux (void);
-extern const struct target_desc *tdesc_amd64_avx_mpx_linux;
-
-/* Defined in auto-generated file amd64-mpx-linux.c.  */
-void init_registers_amd64_mpx_linux (void);
-extern const struct target_desc *tdesc_amd64_mpx_linux;
+#if defined __i386__ || !defined IN_PROCESS_AGENT
+int i386_get_ipa_tdesc_idx (const struct target_desc *tdesc);
 #endif
 
-#if defined __ILP32__ || !defined IN_PROCESS_AGENT
-/* Defined in auto-generated file x32-linux.c.  */
-void init_registers_x32_linux (void);
-extern const struct target_desc *tdesc_x32_linux;
-
-/* Defined in auto-generated file x32-avx-linux.c.  */
-void init_registers_x32_avx_linux (void);
-extern const struct target_desc *tdesc_x32_avx_linux;
-
-/* Defined in auto-generated file x32-avx-avx512-linux.c.  */
-void init_registers_x32_avx_avx512_linux (void);
-extern const struct target_desc *tdesc_x32_avx_avx512_linux;
+#if defined __x86_64__ && !defined IN_PROCESS_AGENT
+int amd64_get_ipa_tdesc_idx (const struct target_desc *tdesc);
 #endif
 
-#endif
+const struct target_desc *i386_get_ipa_tdesc (int idx);
 
-#if defined __i386__ || !defined IN_PROCESS_AGENT
-int i386_get_ipa_tdesc_idx (const struct target_desc *tdesc);
+#ifdef __x86_64__
+const struct target_desc *amd64_linux_read_description (uint64_t xcr0,
+							bool is_x32);
 #endif
 
 const struct target_desc *i386_linux_read_description (uint64_t xcr0);