diff mbox series

[03/12] libgomp: runtime support for target_device selector

Message ID 20240504212153.3561429-4-sloosemore@baylibre.com
State New
Headers show
Series OpenMP: Metadirective support + "declare variant" improvements | expand

Commit Message

Sandra Loosemore May 4, 2024, 9:21 p.m. UTC
This patch implements the libgomp runtime support for the dynamic
target_device selector via the GOMP_evaluate_target_device function.

include/ChangeLog
	* cuda/cuda.h (CUdevice_attribute): Add definitions for
	CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR and
	CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR.

libgomp/ChangeLog
	* Makefile.am (libgomp_la_SOURCES): Add selector.c.
	* Makefile.in: Regenerate.
	* config/gcn/selector.c: New.
	* config/linux/selector.c: New.
	* config/linux/x86/selector.c: New.
	* config/nvptx/selector.c: New.
	* libgomp-plugin.h (GOMP_OFFLOAD_evaluate_device): New.
	* libgomp.h (struct gomp_device_descr): Add evaluate_device_func field.
	* libgomp.map (GOMP_5.1.3): New, add GOMP_evaluate_target_device.
	* libgomp.texi (OpenMP Context Selectors): Document dynamic selector
	matching of kind/arch/isa.
	* libgomp_g.h (GOMP_evaluate_current_device): New.
	(GOMP_evaluate_target_device): New.
	* oacc-host.c (host_evaluate_device): New.
	(host_openacc_exec): Initialize evaluate_device_func field to
	host_evaluate_device.
	* plugin/plugin-gcn.c (gomp_match_selectors): New.
	(gomp_match_isa): New.
	(GOMP_OFFLOAD_evaluate_device): New.
	* plugin/plugin-nvptx.c (struct ptx_device): Add compute_major and
	compute_minor fields.
	(nvptx_open_device): Read compute capability information from device.
	(gomp_match_selectors): New.
	(gomp_match_selector): New.
	(CHECK_ISA): New macro.
	(GOMP_OFFLOAD_evaluate_device): New.
	* selector.c: New.
	* target.c (GOMP_evaluate_target_device): New.
	(gomp_load_plugin_for_device): Load evaluate_device plugin function.

Co-Authored-By: Kwok Cheung Yeung <kcy@codesourcery.com>
Co-Authored-By: Sandra Loosemore <sandra@codesourcery.com>
---
 include/cuda/cuda.h                 |   2 +
 libgomp/Makefile.am                 |   2 +-
 libgomp/Makefile.in                 |   5 +-
 libgomp/config/gcn/selector.c       | 102 +++++++
 libgomp/config/linux/selector.c     |  65 +++++
 libgomp/config/linux/x86/selector.c | 406 ++++++++++++++++++++++++++++
 libgomp/config/nvptx/selector.c     |  77 ++++++
 libgomp/libgomp-plugin.h            |   2 +
 libgomp/libgomp.h                   |   1 +
 libgomp/libgomp.map                 |   5 +
 libgomp/libgomp.texi                |  18 +-
 libgomp/libgomp_g.h                 |   8 +
 libgomp/oacc-host.c                 |  11 +
 libgomp/plugin/plugin-gcn.c         |  52 ++++
 libgomp/plugin/plugin-nvptx.c       |  82 ++++++
 libgomp/selector.c                  |  64 +++++
 libgomp/target.c                    |  40 +++
 17 files changed, 936 insertions(+), 6 deletions(-)
 create mode 100644 libgomp/config/gcn/selector.c
 create mode 100644 libgomp/config/linux/selector.c
 create mode 100644 libgomp/config/linux/x86/selector.c
 create mode 100644 libgomp/config/nvptx/selector.c
 create mode 100644 libgomp/selector.c
diff mbox series

Patch

diff --git a/include/cuda/cuda.h b/include/cuda/cuda.h
index 0dca4b3a5c0..a775450df03 100644
--- a/include/cuda/cuda.h
+++ b/include/cuda/cuda.h
@@ -83,6 +83,8 @@  typedef enum {
   CU_DEVICE_ATTRIBUTE_MAX_THREADS_PER_MULTIPROCESSOR = 39,
   CU_DEVICE_ATTRIBUTE_ASYNC_ENGINE_COUNT = 40,
   CU_DEVICE_ATTRIBUTE_UNIFIED_ADDRESSING = 41,
+  CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR = 75,
+  CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR = 76,
   CU_DEVICE_ATTRIBUTE_MAX_REGISTERS_PER_MULTIPROCESSOR = 82
 } CUdevice_attribute;
 
diff --git a/libgomp/Makefile.am b/libgomp/Makefile.am
index 1871590596d..87658da2d5d 100644
--- a/libgomp/Makefile.am
+++ b/libgomp/Makefile.am
@@ -72,7 +72,7 @@  libgomp_la_SOURCES = alloc.c atomic.c barrier.c critical.c env.c error.c \
 	target.c splay-tree.c libgomp-plugin.c oacc-parallel.c oacc-host.c \
 	oacc-init.c oacc-mem.c oacc-async.c oacc-plugin.c oacc-cuda.c \
 	priority_queue.c affinity-fmt.c teams.c allocator.c oacc-profiling.c \
-	oacc-target.c target-indirect.c
+	oacc-target.c target-indirect.c selector.c
 
 include $(top_srcdir)/plugin/Makefrag.am
 
diff --git a/libgomp/Makefile.in b/libgomp/Makefile.in
index 11480d6a953..30e57571404 100644
--- a/libgomp/Makefile.in
+++ b/libgomp/Makefile.in
@@ -219,7 +219,7 @@  am_libgomp_la_OBJECTS = alloc.lo atomic.lo barrier.lo critical.lo \
 	oacc-parallel.lo oacc-host.lo oacc-init.lo oacc-mem.lo \
 	oacc-async.lo oacc-plugin.lo oacc-cuda.lo priority_queue.lo \
 	affinity-fmt.lo teams.lo allocator.lo oacc-profiling.lo \
-	oacc-target.lo target-indirect.lo $(am__objects_1)
+	oacc-target.lo target-indirect.lo selector.lo $(am__objects_1)
 libgomp_la_OBJECTS = $(am_libgomp_la_OBJECTS)
 AM_V_P = $(am__v_P_@AM_V@)
 am__v_P_ = $(am__v_P_@AM_DEFAULT_V@)
@@ -552,7 +552,7 @@  libgomp_la_SOURCES = alloc.c atomic.c barrier.c critical.c env.c \
 	oacc-parallel.c oacc-host.c oacc-init.c oacc-mem.c \
 	oacc-async.c oacc-plugin.c oacc-cuda.c priority_queue.c \
 	affinity-fmt.c teams.c allocator.c oacc-profiling.c \
-	oacc-target.c target-indirect.c $(am__append_3)
+	oacc-target.c target-indirect.c selector.c $(am__append_3)
 
 # Nvidia PTX OpenACC plugin.
 @PLUGIN_NVPTX_TRUE@libgomp_plugin_nvptx_version_info = -version-info $(libtool_VERSION)
@@ -777,6 +777,7 @@  distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ptrlock.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/scope.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/sections.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/selector.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/sem.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/single.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/splay-tree.Plo@am__quote@
diff --git a/libgomp/config/gcn/selector.c b/libgomp/config/gcn/selector.c
new file mode 100644
index 00000000000..7e099a00b97
--- /dev/null
+++ b/libgomp/config/gcn/selector.c
@@ -0,0 +1,102 @@ 
+/* Copyright (C) 2022 Free Software Foundation, Inc.
+   Contributed by Mentor, a Siemens Business.
+
+   This file is part of the GNU Offloading and Multi Processing Library
+   (libgomp).
+
+   Libgomp 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, or (at your option)
+   any later version.
+
+   Libgomp 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.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file contains an implementation of GOMP_evaluate_current_device for
+   an AMD GCN GPU.  */
+
+#include "libgomp.h"
+#include <string.h>
+
+/* The selectors are passed as strings, but are actually sets of multiple
+   trait property names, separated by '\0' and with an extra '\0' at
+   the end.  Match such a string SELECTORS against an array of strings
+   CHOICES, that is terminated by a null pointer.
+   matches.  */
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+bool
+GOMP_evaluate_current_device (const char *kind, const char *arch,
+			      const char *isa)
+{
+  static const char *kind_choices[] = { "gpu", "nohost", NULL };
+  static const char *arch_choices[] = { "gcn", "amdgcn", NULL };
+  static const char *isa_choices[]
+    = {
+#ifdef __fiji__
+       "fiji", "gfx803",
+#endif
+#ifdef __gfx900__
+       "gfx900",
+#endif
+#ifdef __gfx906__
+       "gfx906",
+#endif
+#ifdef __gfx908__
+       "gfx908",
+#endif
+#ifdef __gfx90a__
+       "gfx90a",
+#endif
+#ifdef __gfx90c__
+       "gfx90c",
+#endif
+#ifdef __gfx1030__
+       "gfx1030",
+#endif
+#ifdef __gfx1036__
+       "gfx1036",
+#endif
+#ifdef __gfx1100__
+       "gfx1100",
+#endif
+#ifdef __gfx1103__
+       "gfx1103",
+#endif
+       NULL };
+
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+
+  if (arch && !gomp_match_selectors (arch, arch_choices))
+    return false;
+
+  if (isa && !gomp_match_selectors (isa, isa_choices))
+    return false;
+
+  return true;
+}
diff --git a/libgomp/config/linux/selector.c b/libgomp/config/linux/selector.c
new file mode 100644
index 00000000000..064cb937ecc
--- /dev/null
+++ b/libgomp/config/linux/selector.c
@@ -0,0 +1,65 @@ 
+/* Copyright (C) 2022 Free Software Foundation, Inc.
+   Contributed by Mentor, a Siemens Business.
+
+   This file is part of the GNU Offloading and Multi Processing Library
+   (libgomp).
+
+   Libgomp 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, or (at your option)
+   any later version.
+
+   Libgomp 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.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file contains a generic implementation of
+   GOMP_evaluate_current_device when run on a Linux host.  */
+
+#include <string.h>
+#include "libgomp.h"
+
+/* The selectors are passed as strings, but are actually sets of multiple
+   trait property names, separated by '\0' and with an extra '\0' at
+   the end.  Match such a string SELECTORS against an array of strings
+   CHOICES, that is terminated by a null pointer.
+   matches.  */
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+bool
+GOMP_evaluate_current_device (const char *kind, const char *arch,
+			      const char *isa)
+{
+  static const char *kind_choices[] = { "cpu", "host", NULL };
+
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+
+  if (arch || isa)
+    return false;
+
+  return true;
+}
diff --git a/libgomp/config/linux/x86/selector.c b/libgomp/config/linux/x86/selector.c
new file mode 100644
index 00000000000..13cd2e14389
--- /dev/null
+++ b/libgomp/config/linux/x86/selector.c
@@ -0,0 +1,406 @@ 
+/* Copyright (C) 2022 Free Software Foundation, Inc.
+   Contributed by Mentor, a Siemens Business.
+
+   This file is part of the GNU Offloading and Multi Processing Library
+   (libgomp).
+
+   Libgomp 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, or (at your option)
+   any later version.
+
+   Libgomp 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.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file contains an implementation of GOMP_evaluate_current_device for
+   an x86/x64-based Linux host.  */
+
+#include <string.h>
+#include "libgomp.h"
+
+/* The selectors are passed as strings, but are actually sets of multiple
+   trait property names, separated by '\0' and with an extra '\0' at
+   the end.  Match such a string SELECTORS against an array of strings
+   CHOICES, that is terminated by a null pointer.
+   matches.  */
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+bool
+GOMP_evaluate_current_device (const char *kind, const char *arch,
+			      const char *isa)
+{
+  static const char *kind_choices[] = { "cpu", "host", NULL };
+
+  static const char *arch_choices[]
+    = { "x86",
+	"ia32",
+#ifdef __x86_64__
+	"x86_64",
+#endif
+#ifdef __ILP32__
+	"x32",
+#endif
+	"i386",
+#ifdef __i486__
+	"i486",
+#endif
+#ifdef __i586__
+	"i586",
+#endif
+#ifdef __i686__
+	"i686",
+#endif
+	NULL };
+
+  static const char *isa_choices[]
+    = {
+#ifdef __WBNOINVD__
+       "wbnoinvd",
+#endif
+#ifdef __AVX512VP2INTERSECT__
+       "avx512vp2intersect",
+#endif
+#ifdef __MMX__
+       "mmx",
+#endif
+#ifdef __3dNOW__
+       "3dnow",
+#endif
+#ifdef __3dNOW_A__
+       "3dnowa",
+#endif
+#ifdef __SSE__
+       "sse",
+#endif
+#ifdef __SSE2__
+       "sse2",
+#endif
+#ifdef __SSE3__
+       "sse3",
+#endif
+#ifdef __SSSE3__
+       "ssse3",
+#endif
+#ifdef __SSE4_1__
+       "sse4.1",
+#endif
+#ifdef __SSE4_2__
+       "sse4",
+       "sse4.2",
+#endif
+#ifdef __AES__
+       "aes",
+#endif
+#ifdef __SHA__
+       "sha",
+#endif
+#ifdef __PCLMUL__
+       "pclmul",
+#endif
+#ifdef __AVX__
+       "avx",
+#endif
+#ifdef __AVX2__
+       "avx2",
+#endif
+#ifdef __AVX512F__
+  "avx512f",
+#endif
+#ifdef __AVX512ER__
+       "avx512er",
+#endif
+#ifdef __AVX512CD__
+       "avx512cd",
+#endif
+#ifdef __AVX512PF__
+       "avx512pf",
+#endif
+#ifdef __AVX512DQ__
+       "avx512dq",
+#endif
+#ifdef __AVX512BW__
+       "avx512bw",
+#endif
+#ifdef __AVX512VL__
+       "avx512vl",
+#endif
+#ifdef __AVX512VBMI__
+       "avx512vbmi",
+#endif
+#ifdef __AVX512IFMA__
+       "avx512ifma",
+#endif
+#ifdef __AVX5124VNNIW__
+       "avx5124vnniw",
+#endif
+#ifdef __AVX512VBMI2__
+       "avx512vbmi2",
+#endif
+#ifdef __AVX512VNNI__
+       "avx512vnni",
+#endif
+#ifdef __PCONFIG__
+       "pconfig",
+#endif
+#ifdef __SGX__
+       "sgx",
+#endif
+#ifdef __AVX5124FMAPS__
+       "avx5124fmaps",
+#endif
+#ifdef __AVX512BITALG__
+       "avx512bitalg",
+#endif
+#ifdef __AVX512VPOPCNTDQ__
+       "avx512vpopcntdq",
+#endif
+#ifdef __FMA__
+       "fma",
+#endif
+#ifdef __RTM__
+       "rtm",
+#endif
+#ifdef __SSE4A__
+       "sse4a",
+#endif
+#ifdef __FMA4__
+       "fma4",
+#endif
+#ifdef __XOP__
+       "xop",
+#endif
+#ifdef __LWP__
+       "lwp",
+#endif
+#ifdef __ABM__
+       "abm",
+#endif
+#ifdef __BMI__
+       "bmi",
+#endif
+#ifdef __BMI2__
+       "bmi2",
+#endif
+#ifdef __LZCNT__
+       "lzcnt",
+#endif
+#ifdef __TBM__
+       "tbm",
+#endif
+#ifdef __CRC32__
+       "crc32",
+#endif
+#ifdef __POPCNT__
+       "popcnt",
+#endif
+#ifdef __FSGSBASE__
+       "fsgsbase",
+#endif
+#ifdef __RDRND__
+       "rdrnd",
+#endif
+#ifdef __F16C__
+       "f16c",
+#endif
+#ifdef __RDSEED__
+       "rdseed",
+#endif
+#ifdef __PRFCHW__
+       "prfchw",
+#endif
+#ifdef __ADX__
+       "adx",
+#endif
+#ifdef __FXSR__
+       "fxsr",
+#endif
+#ifdef __XSAVE__
+       "xsave",
+#endif
+#ifdef __XSAVEOPT__
+       "xsaveopt",
+#endif
+#ifdef __PREFETCHWT1__
+       "prefetchwt1",
+#endif
+#ifdef __CLFLUSHOPT__
+       "clflushopt",
+#endif
+#ifdef __CLZERO__
+       "clzero",
+#endif
+#ifdef __XSAVEC__
+       "xsavec",
+#endif
+#ifdef __XSAVES__
+       "xsaves",
+#endif
+#ifdef __CLWB__
+       "clwb",
+#endif
+#ifdef __MWAITX__
+       "mwaitx",
+#endif
+#ifdef __PKU__
+       "pku",
+#endif
+#ifdef __RDPID__
+       "rdpid",
+#endif
+#ifdef __GFNI__
+       "gfni",
+#endif
+#ifdef __SHSTK__
+       "shstk",
+#endif
+#ifdef __VAES__
+       "vaes",
+#endif
+#ifdef __VPCLMULQDQ__
+       "vpclmulqdq",
+#endif
+#ifdef __MOVDIRI__
+       "movdiri",
+#endif
+#ifdef __MOVDIR64B__
+       "movdir64b",
+#endif
+#ifdef __WAITPKG__
+       "waitpkg",
+#endif
+#ifdef __CLDEMOTE__
+       "cldemote",
+#endif
+#ifdef __SERIALIZE__
+       "serialize",
+#endif
+#ifdef __PTWRITE__
+       "ptwrite",
+#endif
+#ifdef __AVX512BF16__
+       "avx512bf16",
+#endif
+#ifdef __AVX512FP16__
+       "avx512fp16",
+#endif
+#ifdef __ENQCMD__
+       "enqcmd",
+#endif
+#ifdef __TSXLDTRK__
+       "tsxldtrk",
+#endif
+#ifdef __AMX_TILE__
+       "amx-tile",
+#endif
+#ifdef __AMX_INT8__
+       "amx-int8",
+#endif
+#ifdef __AMX_BF16__
+       "amx-bf16",
+#endif
+#ifdef __LAHF_SAHF__
+       "sahf",
+#endif
+#ifdef __MOVBE__
+       "movbe",
+#endif
+#ifdef __UINTR__
+       "uintr",
+#endif
+#ifdef __HRESET__
+       "hreset",
+#endif
+#ifdef __KL__
+       "kl",
+#endif
+#ifdef __WIDEKL__
+       "widekl",
+#endif
+#ifdef __AVXVNNI__
+       "avxvnni",
+#endif
+#ifdef __AVXIFMA_
+       "avxifma",_
+#endif
+#ifdef __AVXVNNIINT8__
+       "avxvnniint8",
+#endif
+#ifdef __AVXNECONVERT__
+       "avxneconvert",
+#endif
+#ifdef __CMPCCXADD__
+       "cmpccxadd",
+#endif
+#ifdef __AMX_FP16__
+       "amx-fp16",
+#endif
+#ifdef __PREFETCHI__
+       "prefetchi",
+#endif
+#ifdef __RAOINT__
+       "raoint",
+#endif
+#ifdef __AMX_COMPLEX__
+       "amx-complex",
+#endif
+#ifdef __AVXVNNIINT16__
+       "amxvnniint16",
+#endif
+#ifdef __SM3__
+       "sm3",
+#endif
+#ifdef __SHA512__
+       "sha512",
+#endif
+#ifdef __SM4__
+       "sm4",
+#endif
+#ifdef __EVEX512__
+       "evex512",
+#endif
+#ifdef __USER_MSR__
+       "usermsr",
+#endif
+#ifdef __AVX10_1_256__
+       "avx10.1-256",
+#endif
+#ifdef __AVX10_1_512__
+       "avx10.1-512",
+#endif
+#ifdef __APX_F__
+       "apxf",
+#endif
+       NULL };
+
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+  if (arch && !gomp_match_selectors (arch, arch_choices))
+    return false;
+  if (isa && !gomp_match_selectors (isa, isa_choices))
+    return false;
+  return true;
+}
diff --git a/libgomp/config/nvptx/selector.c b/libgomp/config/nvptx/selector.c
new file mode 100644
index 00000000000..c1e81efca28
--- /dev/null
+++ b/libgomp/config/nvptx/selector.c
@@ -0,0 +1,77 @@ 
+/* Copyright (C) 2022 Free Software Foundation, Inc.
+   Contributed by Mentor, a Siemens Business.
+
+   This file is part of the GNU Offloading and Multi Processing Library
+   (libgomp).
+
+   Libgomp 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, or (at your option)
+   any later version.
+
+   Libgomp 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.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file contains an implementation of GOMP_evaluate_current_device for
+   a Nvidia GPU.  */
+
+#include "libgomp.h"
+#include <string.h>
+
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+bool
+GOMP_evaluate_current_device (const char *kind, const char *arch,
+			      const char *isa)
+{
+  static const char *kind_choices[] = { "gpu", "nohost", NULL };
+  static const char *arch_choices[] = { "nvptx", NULL };
+  static const char *isa_choices[]
+    = {
+       "sm_30",
+#if __PTX_SM__ >= 350
+       "sm_35",
+#endif
+#if __PTX_SM__ >= 530
+       "sm_53",
+#endif
+#if __PTX_SM__ >= 750
+       "sm_75",
+#endif
+#if __PTX_SM__ >= 800
+       "sm_80",
+#endif
+       NULL };
+
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+  if (arch && !gomp_match_selectors (arch, arch_choices))
+    return false;
+  if (isa && !gomp_match_selectors (isa, isa_choices))
+    return false;
+  return true;
+}
diff --git a/libgomp/libgomp-plugin.h b/libgomp/libgomp-plugin.h
index 0c9c28c65cf..73f880ffa2f 100644
--- a/libgomp/libgomp-plugin.h
+++ b/libgomp/libgomp-plugin.h
@@ -152,6 +152,8 @@  extern int GOMP_OFFLOAD_memcpy3d (int, int, size_t, size_t, size_t, void *,
 extern bool GOMP_OFFLOAD_can_run (void *);
 extern void GOMP_OFFLOAD_run (int, void *, void *, void **);
 extern void GOMP_OFFLOAD_async_run (int, void *, void *, void **, void *);
+extern bool GOMP_OFFLOAD_evaluate_device (int, const char *, const char *,
+					  const char *);
 
 extern void GOMP_OFFLOAD_openacc_exec (void (*) (void *), size_t, void **,
 				       void **, unsigned *, void *);
diff --git a/libgomp/libgomp.h b/libgomp/libgomp.h
index 089393846d1..4dad4bc321a 100644
--- a/libgomp/libgomp.h
+++ b/libgomp/libgomp.h
@@ -1417,6 +1417,7 @@  struct gomp_device_descr
   __typeof (GOMP_OFFLOAD_can_run) *can_run_func;
   __typeof (GOMP_OFFLOAD_run) *run_func;
   __typeof (GOMP_OFFLOAD_async_run) *async_run_func;
+  __typeof (GOMP_OFFLOAD_evaluate_device) *evaluate_device_func;
 
   /* Splay tree containing information about mapped memory regions.  */
   struct splay_tree_s mem_map;
diff --git a/libgomp/libgomp.map b/libgomp/libgomp.map
index 65901dff235..70a48874417 100644
--- a/libgomp/libgomp.map
+++ b/libgomp/libgomp.map
@@ -428,6 +428,11 @@  GOMP_5.1.2 {
 	GOMP_target_map_indirect_ptr;
 } GOMP_5.1.1;
 
+GOMP_5.1.3 {
+  global:
+	GOMP_evaluate_target_device;
+} GOMP_5.1.2;
+
 OACC_2.0 {
   global:
 	acc_get_num_devices;
diff --git a/libgomp/libgomp.texi b/libgomp/libgomp.texi
index 71d62105a20..43048da4d6e 100644
--- a/libgomp/libgomp.texi
+++ b/libgomp/libgomp.texi
@@ -6181,9 +6181,10 @@  smaller number.  On non-host devices, the value of the
 @c has to be implemented; cf. also PR target/105640.
 @c For offload devices, add *additionally* gcc/config/*/t-omp-device.
 
-For the host compiler, @code{kind} always matches @code{host}; for the
-offloading architectures AMD GCN and Nvidia PTX, @code{kind} always matches
-@code{gpu}.  For the x86 family of computers, AMD GCN and Nvidia PTX
+For the host compiler, @code{kind} always matches @code{host} and @code{cpu};
+for the offloading architectures AMD GCN and Nvidia PTX, @code{kind}
+always matches @code{gpu} and @code{nohost}.
+For the x86 family of computers, AMD GCN and Nvidia PTX
 the following traits are supported in addition; while OpenMP is supported
 on more architectures, GCC currently does not match any @code{arch} or
 @code{isa} traits for those.
@@ -6200,6 +6201,17 @@  on more architectures, GCC currently does not match any @code{arch} or
       @tab See @code{-march=} in ``Nvidia PTX Options''
 @end multitable
 
+For x86, note that the set of matching @code{arch} and @code{isa}
+selectors is determined by command-line options rather than the actual
+hardware.  This is particularly true of dynamic selectors, which match
+the options used to build libgomp rather than the options used to
+build user programs (which may also differ between compilation units).
+
+For the @code{target_device} selector on AMD GCN and Nvidia PTX,
+the actual hardware is checked at run time.  On AMD GCN, an exact match
+of the @code{isa} selector is required, while on Nvidia PTX lower-numbered
+revisions also match.
+
 @node Memory allocation
 @section Memory allocation
 
diff --git a/libgomp/libgomp_g.h b/libgomp/libgomp_g.h
index c0cc03ae61f..e9d60238e2b 100644
--- a/libgomp/libgomp_g.h
+++ b/libgomp/libgomp_g.h
@@ -337,6 +337,11 @@  extern void GOMP_single_copy_end (void *);
 
 extern void GOMP_scope_start (uintptr_t *);
 
+/* selector.c */
+
+extern bool GOMP_evaluate_current_device (const char *, const char *,
+					  const char *);
+
 /* target.c */
 
 extern void GOMP_target (int, void (*) (void *), const void *,
@@ -359,6 +364,9 @@  extern void GOMP_teams (unsigned int, unsigned int);
 extern bool GOMP_teams4 (unsigned int, unsigned int, unsigned int, bool);
 extern void *GOMP_target_map_indirect_ptr (void *);
 
+extern bool GOMP_evaluate_target_device (int, const char *, const char *,
+					 const char *);
+
 /* teams.c */
 
 extern void GOMP_teams_reg (void (*) (void *), void *, unsigned, unsigned,
diff --git a/libgomp/oacc-host.c b/libgomp/oacc-host.c
index 5efdf7fb796..b6883850250 100644
--- a/libgomp/oacc-host.c
+++ b/libgomp/oacc-host.c
@@ -136,6 +136,16 @@  host_run (int n __attribute__ ((unused)), void *fn_ptr, void *vars,
   fn (vars);
 }
 
+static bool
+host_evaluate_device (int device_num __attribute__ ((unused)),
+		      const char *kind __attribute__ ((unused)),
+		      const char *arch __attribute__ ((unused)),
+		      const char *isa __attribute__ ((unused)))
+{
+  __builtin_unreachable ();
+  return false;
+}
+
 static void
 host_openacc_exec (void (*fn) (void *),
 		   size_t mapnum __attribute__ ((unused)),
@@ -285,6 +295,7 @@  static struct gomp_device_descr host_dispatch =
     .memcpy2d_func = NULL,
     .memcpy3d_func = NULL,
     .run_func = host_run,
+    .evaluate_device_func = host_evaluate_device,
 
     .mem_map = { NULL },
     .mem_map_rev = { NULL },
diff --git a/libgomp/plugin/plugin-gcn.c b/libgomp/plugin/plugin-gcn.c
index 3cdc7ba929f..9d9f34cf767 100644
--- a/libgomp/plugin/plugin-gcn.c
+++ b/libgomp/plugin/plugin-gcn.c
@@ -4395,6 +4395,58 @@  GOMP_OFFLOAD_async_run (int device, void *tgt_fn, void *tgt_vars,
 		       GOMP_PLUGIN_target_task_completion, async_data);
 }
 
+/* The selectors are passed as strings, but are actually sets of multiple
+   trait property names, separated by '\0' and with an extra '\0' at
+   the end.  Match such a string SELECTORS against an array of strings
+   CHOICES, that is terminated by a null pointer.
+   matches.  */
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+/* Here we can only have one possible match and it must be
+   the only selector provided.  */
+static bool
+gomp_match_isa (const char *selectors, gcn_isa isa)
+{
+  if (isa_code (selectors) != isa)
+    return false;
+  if (*(selectors + strlen (selectors) + 1) != '\0')
+    return false;
+  return true;
+}
+
+bool
+GOMP_OFFLOAD_evaluate_device (int device_num, const char *kind,
+			      const char *arch, const char *isa)
+{
+  static const char *kind_choices[] = { "gpu", "nohost", NULL };
+  static const char *arch_choices[] = { "gcn", "amdgcn", NULL };
+  struct agent_info *agent = get_agent_info (device_num);
+
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+
+  if (arch && !gomp_match_selectors (arch, arch_choices))
+    return false;
+
+  if (isa && !gomp_match_isa (isa, agent->device_isa))
+    return false;
+
+  return true;
+}
+
 /* }}} */
 /* {{{ OpenACC Plugin API  */
 
diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c
index 5aad3448a8d..5126720eb5c 100644
--- a/libgomp/plugin/plugin-nvptx.c
+++ b/libgomp/plugin/plugin-nvptx.c
@@ -317,6 +317,7 @@  struct ptx_device
   int max_threads_per_block;
   int max_threads_per_multiprocessor;
   int default_dims[GOMP_DIM_MAX];
+  int compute_major, compute_minor;
 
   /* Length as used by the CUDA Runtime API ('struct cudaDeviceProp').  */
   char name[256];
@@ -541,6 +542,14 @@  nvptx_open_device (int n)
   for (int i = 0; i != GOMP_DIM_MAX; i++)
     ptx_dev->default_dims[i] = 0;
 
+  CUDA_CALL_ERET (NULL, cuDeviceGetAttribute, &pi,
+		  CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR, dev);
+  ptx_dev->compute_major = pi;
+
+  CUDA_CALL_ERET (NULL, cuDeviceGetAttribute, &pi,
+		  CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR, dev);
+  ptx_dev->compute_minor = pi;
+
   CUDA_CALL_ERET (NULL, cuDeviceGetName, ptx_dev->name, sizeof ptx_dev->name,
 		  dev);
 
@@ -2314,3 +2323,76 @@  GOMP_OFFLOAD_run (int ord, void *tgt_fn, void *tgt_vars, void **args)
 }
 
 /* TODO: Implement GOMP_OFFLOAD_async_run. */
+
+/* The selectors are passed as strings, but are actually sets of multiple
+   trait property names, separated by '\0' and with an extra '\0' at
+   the end.  Match such a string SELECTORS against an array of strings
+   CHOICES, that is terminated by a null pointer.
+   matches.  */
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+/* Here we can only have one possible match and it must be
+   the only selector provided.  */
+static bool
+gomp_match_selector (const char *selectors, const char *choice)
+{
+  if (!strcmp (selectors, choice))
+    return false;
+  if (*(selectors + strlen (selectors) + 1) != '\0')
+    return false;
+  return true;
+}
+
+#define CHECK_ISA(major, minor)					\
+  if (device->compute_major >= major				\
+      && device->compute_minor >= minor				\
+      && gomp_match_selector (isa, "sm_"#major#minor))		\
+    return true
+
+bool
+GOMP_OFFLOAD_evaluate_device (int device_num, const char *kind,
+			      const char *arch, const char *isa)
+{
+  static const char *kind_choices[] = { "gpu", "nohost", NULL };
+  static const char *arch_choices[] = { "nvptx", NULL };
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+
+  if (arch && !gomp_match_selectors (arch, arch_choices))
+    return false;
+
+  if (!isa)
+    return true;
+
+  struct ptx_device *device = ptx_devices[device_num];
+
+  CHECK_ISA (3, 0);
+  CHECK_ISA (3, 5);
+  CHECK_ISA (3, 7);
+  CHECK_ISA (5, 0);
+  CHECK_ISA (5, 2);
+  CHECK_ISA (5, 3);
+  CHECK_ISA (6, 0);
+  CHECK_ISA (6, 1);
+  CHECK_ISA (6, 2);
+  CHECK_ISA (7, 0);
+  CHECK_ISA (7, 2);
+  CHECK_ISA (7, 5);
+  CHECK_ISA (8, 0);
+  CHECK_ISA (8, 6);
+
+  return false;
+}
diff --git a/libgomp/selector.c b/libgomp/selector.c
new file mode 100644
index 00000000000..5b21e582844
--- /dev/null
+++ b/libgomp/selector.c
@@ -0,0 +1,64 @@ 
+/* Copyright (C) 2022 Free Software Foundation, Inc.
+   Contributed by Mentor, a Siemens Business.
+
+   This file is part of the GNU Offloading and Multi Processing Library
+   (libgomp).
+
+   Libgomp 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, or (at your option)
+   any later version.
+
+   Libgomp 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.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file contains a placeholder implementation of
+   GOMP_evaluate_current_device.  */
+
+#include "libgomp.h"
+
+/* The selectors are passed as strings, but are actually sets of multiple
+   trait property names, separated by '\0' and with an extra '\0' at
+   the end.  Match such a string SELECTORS against an array of strings
+   CHOICES, that is terminated by a null pointer.
+   matches.  */
+static bool
+gomp_match_selectors (const char *selectors, const char **choices)
+{
+  while (*selectors != '\0')
+    {
+      bool match = false;
+      for (int i = 0; !match && choices[i]; i++)
+	match = !strcmp (selectors, choices[i]);
+      if (!match)
+	return false;
+      selectors += strlen (selectors) + 1;
+    }
+  return true;
+}
+
+bool
+GOMP_evaluate_current_device (const char *kind, const char *arch,
+			      const char *isa)
+{
+  static const char *kind_choices[] = { "cpu", "host", NULL };
+
+  if (kind && !gomp_match_selectors (kind, kind_choices))
+    return false;
+
+  if (arch || isa)
+    return false;
+
+  return true;
+}
diff --git a/libgomp/target.c b/libgomp/target.c
index 5ec19ae489e..02973ee2f40 100644
--- a/libgomp/target.c
+++ b/libgomp/target.c
@@ -5092,6 +5092,45 @@  omp_pause_resource_all (omp_pause_resource_t kind)
 ialias (omp_pause_resource)
 ialias (omp_pause_resource_all)
 
+bool
+GOMP_evaluate_target_device (int device_num, const char *kind,
+			     const char *arch, const char *isa)
+{
+  bool result = true;
+
+  /* -2 is a magic number to indicate the device number was not specified;
+     in that case it's supposed to use the default device.  */
+  if (device_num == -2)
+    device_num = omp_get_default_device ();
+
+  if (kind && strcmp (kind, "any") == 0)
+    kind = NULL;
+
+  gomp_debug (1, "%s: device_num = %u, kind=%s, arch=%s, isa=%s",
+	      __FUNCTION__, device_num, kind, arch, isa);
+
+  if (omp_get_device_num () == device_num)
+    result = GOMP_evaluate_current_device (kind, arch, isa);
+  else
+    {
+      if (!omp_is_initial_device ())
+	/* Accelerators are not expected to know about other devices.  */
+	result = false;
+      else
+	{
+	  struct gomp_device_descr *device = resolve_device (device_num, true);
+	  if (device == NULL)
+	    result = false;
+	  else if (device->evaluate_device_func)
+	    result = device->evaluate_device_func (device_num, kind, arch,
+						   isa);
+	}
+    }
+
+  gomp_debug (1, " -> %s\n", result ? "true" : "false");
+  return result;
+}
+
 #ifdef PLUGIN_SUPPORT
 
 /* This function tries to load a plugin for DEVICE.  Name of plugin is passed
@@ -5144,6 +5183,7 @@  gomp_load_plugin_for_device (struct gomp_device_descr *device,
   DLSYM (free);
   DLSYM (dev2host);
   DLSYM (host2dev);
+  DLSYM (evaluate_device);
   DLSYM_OPT (memcpy2d, memcpy2d);
   DLSYM_OPT (memcpy3d, memcpy3d);
   device->capabilities = device->get_caps_func ();