[nvptx libgomp plugin] Build only in supported configurations

As recently again discussed in <https://gcc.gnu.org/PR97436> "[nvptx] -m32
support", nvptx offloading other than for 64-bit host has never been
implemented, tested, supported.  So we simply should buildn't the nvptx libgomp
plugin in this case.

This avoids build problems if, for example, in a (standard) bi-arch
x86_64-pc-linux-gnu '-m64'/'-m32' build, libcuda is available only in a 64-bit
variant but not in a 32-bit one, which, for example, is the case if you build
GCC against the CUDA toolkit's 'stubs/libcuda.so' (see
<https://stackoverflow.com/a/52784819>).

This amends PR65099 commit a92defdab79a1268f4b9dcf42b937e4002a4cf15 (r225560)
"[nvptx offloading] Only 64-bit configurations are currently supported" to
match the way we're doing this for the HSA/GCN plugins.

	libgomp/
	PR libgomp/65099
	* plugin/configfrag.ac (PLUGIN_NVPTX): Restrict to supported
	configurations.
	* configure: Regenerate.
	* plugin/plugin-nvptx.c (nvptx_get_num_devices): Remove 64-bit
	check.

diff --git a/libgomp/configure b/libgomp/configure
index 89c17c571b70e425f88c6b8acb84843124649612..48bf8e4a72c4792ff1c32257e415a817be9096dd 100755 (executable)
--- a/libgomp/configure
+++ b/libgomp/configure
@@ -15272,21 +15272,30 @@ if test x"$enable_offload_targets" != x; then
        tgt_plugin=intelmic
        ;;
       nvptx*)
-       tgt_plugin=nvptx
-       PLUGIN_NVPTX=$tgt
-       if test "x$CUDA_DRIVER_LIB" != xno \
-          && test "x$CUDA_DRIVER_LIB" != xno; then
-         PLUGIN_NVPTX_CPPFLAGS=$CUDA_DRIVER_CPPFLAGS
-         PLUGIN_NVPTX_LDFLAGS=$CUDA_DRIVER_LDFLAGS
-         PLUGIN_NVPTX_LIBS='-lcuda'
-
-         PLUGIN_NVPTX_save_CPPFLAGS=$CPPFLAGS
-         CPPFLAGS="$PLUGIN_NVPTX_CPPFLAGS $CPPFLAGS"
-         PLUGIN_NVPTX_save_LDFLAGS=$LDFLAGS
-         LDFLAGS="$PLUGIN_NVPTX_LDFLAGS $LDFLAGS"
-         PLUGIN_NVPTX_save_LIBS=$LIBS
-         LIBS="$PLUGIN_NVPTX_LIBS $LIBS"
-         cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+       case "${target}" in
+         aarch64*-*-* | powerpc64le-*-* | x86_64-*-*)
+           case " ${CC} ${CFLAGS} " in
+             *" -m32 "* | *" -mx32 "*)
+               # PR libgomp/65099: Currently, we only support offloading in
+               # 64-bit configurations.
+               PLUGIN_NVPTX=0
+               ;;
+             *)
+               tgt_plugin=nvptx
+               PLUGIN_NVPTX=$tgt
+               if test "x$CUDA_DRIVER_LIB" != xno \
+                  && test "x$CUDA_DRIVER_LIB" != xno; then
+                 PLUGIN_NVPTX_CPPFLAGS=$CUDA_DRIVER_CPPFLAGS
+                 PLUGIN_NVPTX_LDFLAGS=$CUDA_DRIVER_LDFLAGS
+                 PLUGIN_NVPTX_LIBS='-lcuda'
+
+                 PLUGIN_NVPTX_save_CPPFLAGS=$CPPFLAGS
+                 CPPFLAGS="$PLUGIN_NVPTX_CPPFLAGS $CPPFLAGS"
+                 PLUGIN_NVPTX_save_LDFLAGS=$LDFLAGS
+                 LDFLAGS="$PLUGIN_NVPTX_LDFLAGS $LDFLAGS"
+                 PLUGIN_NVPTX_save_LIBS=$LIBS
+                 LIBS="$PLUGIN_NVPTX_LIBS $LIBS"
+                 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 #include "cuda.h"
 int
@@ -15302,28 +15311,35 @@ if ac_fn_c_try_link "$LINENO"; then :
 fi
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext conftest.$ac_ext
-         CPPFLAGS=$PLUGIN_NVPTX_save_CPPFLAGS
-         LDFLAGS=$PLUGIN_NVPTX_save_LDFLAGS
-         LIBS=$PLUGIN_NVPTX_save_LIBS
-       fi
-       case $PLUGIN_NVPTX in
-         nvptx*)
-           if (test "x$CUDA_DRIVER_INCLUDE" = x \
-               || test "x$CUDA_DRIVER_INCLUDE" = xno) \
-              && (test "x$CUDA_DRIVER_LIB" = x \
-                  || test "x$CUDA_DRIVER_LIB" = xno); then
-             PLUGIN_NVPTX=1
-             PLUGIN_NVPTX_CPPFLAGS='-I$(srcdir)/plugin/cuda'
-             PLUGIN_NVPTX_LIBS='-ldl'
-             PLUGIN_NVPTX_DYNAMIC=1
-           else
-             PLUGIN_NVPTX=0
-             as_fn_error $? "CUDA driver package required for nvptx support" "$LINENO" 5
-           fi
-         ;;
+                 CPPFLAGS=$PLUGIN_NVPTX_save_CPPFLAGS
+                 LDFLAGS=$PLUGIN_NVPTX_save_LDFLAGS
+                 LIBS=$PLUGIN_NVPTX_save_LIBS
+               fi
+               case $PLUGIN_NVPTX in
+                 nvptx*)
+                   if (test "x$CUDA_DRIVER_INCLUDE" = x \
+                       || test "x$CUDA_DRIVER_INCLUDE" = xno) \
+                      && (test "x$CUDA_DRIVER_LIB" = x \
+                          || test "x$CUDA_DRIVER_LIB" = xno); then
+                     PLUGIN_NVPTX=1
+                     PLUGIN_NVPTX_CPPFLAGS='-I$(srcdir)/plugin/cuda'
+                     PLUGIN_NVPTX_LIBS='-ldl'
+                     PLUGIN_NVPTX_DYNAMIC=1
+                   else
+                     PLUGIN_NVPTX=0
+                     as_fn_error $? "CUDA driver package required for nvptx support" "$LINENO" 5
+                   fi
+                   ;;
+               esac
+               ;;
+           esac
+           ;;
+         *-*-*)
+           # Target architecture not supported.
+           PLUGIN_NVPTX=0
+           ;;
        esac
        ;;
-
       amdgcn*)
        case "${target}" in
          x86_64-*-*)

diff --git a/libgomp/plugin/configfrag.ac b/libgomp/plugin/configfrag.ac
index 2e086c017fed09c6bd1117be7e1eb6b79ebe26ef..88550982eabe9ad309fe54a52efd28076a7b420f 100644 (file)
--- a/libgomp/plugin/configfrag.ac
+++ b/libgomp/plugin/configfrag.ac
@@ -158,47 +158,63 @@ if test x"$enable_offload_targets" != x; then
        tgt_plugin=intelmic
        ;;
       nvptx*)
-       tgt_plugin=nvptx
-       PLUGIN_NVPTX=$tgt
-       if test "x$CUDA_DRIVER_LIB" != xno \
-          && test "x$CUDA_DRIVER_LIB" != xno; then
-         PLUGIN_NVPTX_CPPFLAGS=$CUDA_DRIVER_CPPFLAGS
-         PLUGIN_NVPTX_LDFLAGS=$CUDA_DRIVER_LDFLAGS
-         PLUGIN_NVPTX_LIBS='-lcuda'
+       case "${target}" in
+         aarch64*-*-* | powerpc64le-*-* | x86_64-*-*)
+           case " ${CC} ${CFLAGS} " in
+             *" -m32 "* | *" -mx32 "*)
+               # PR libgomp/65099: Currently, we only support offloading in
+               # 64-bit configurations.
+               PLUGIN_NVPTX=0
+               ;;
+             *)
+               tgt_plugin=nvptx
+               PLUGIN_NVPTX=$tgt
+               if test "x$CUDA_DRIVER_LIB" != xno \
+                  && test "x$CUDA_DRIVER_LIB" != xno; then
+                 PLUGIN_NVPTX_CPPFLAGS=$CUDA_DRIVER_CPPFLAGS
+                 PLUGIN_NVPTX_LDFLAGS=$CUDA_DRIVER_LDFLAGS
+                 PLUGIN_NVPTX_LIBS='-lcuda'
 
-         PLUGIN_NVPTX_save_CPPFLAGS=$CPPFLAGS
-         CPPFLAGS="$PLUGIN_NVPTX_CPPFLAGS $CPPFLAGS"
-         PLUGIN_NVPTX_save_LDFLAGS=$LDFLAGS
-         LDFLAGS="$PLUGIN_NVPTX_LDFLAGS $LDFLAGS"
-         PLUGIN_NVPTX_save_LIBS=$LIBS
-         LIBS="$PLUGIN_NVPTX_LIBS $LIBS"
-         AC_LINK_IFELSE(
-           [AC_LANG_PROGRAM(
-             [#include "cuda.h"],
-               [CUresult r = cuCtxPushCurrent (NULL);])],
-           [PLUGIN_NVPTX=1])
-         CPPFLAGS=$PLUGIN_NVPTX_save_CPPFLAGS
-         LDFLAGS=$PLUGIN_NVPTX_save_LDFLAGS
-         LIBS=$PLUGIN_NVPTX_save_LIBS
-       fi
-       case $PLUGIN_NVPTX in
-         nvptx*)
-           if (test "x$CUDA_DRIVER_INCLUDE" = x \
-               || test "x$CUDA_DRIVER_INCLUDE" = xno) \
-              && (test "x$CUDA_DRIVER_LIB" = x \
-                  || test "x$CUDA_DRIVER_LIB" = xno); then
-             PLUGIN_NVPTX=1
-             PLUGIN_NVPTX_CPPFLAGS='-I$(srcdir)/plugin/cuda'
-             PLUGIN_NVPTX_LIBS='-ldl'
-             PLUGIN_NVPTX_DYNAMIC=1
-           else
-             PLUGIN_NVPTX=0
-             AC_MSG_ERROR([CUDA driver package required for nvptx support])
-           fi
-         ;;
+                 PLUGIN_NVPTX_save_CPPFLAGS=$CPPFLAGS
+                 CPPFLAGS="$PLUGIN_NVPTX_CPPFLAGS $CPPFLAGS"
+                 PLUGIN_NVPTX_save_LDFLAGS=$LDFLAGS
+                 LDFLAGS="$PLUGIN_NVPTX_LDFLAGS $LDFLAGS"
+                 PLUGIN_NVPTX_save_LIBS=$LIBS
+                 LIBS="$PLUGIN_NVPTX_LIBS $LIBS"
+                 AC_LINK_IFELSE(
+                   [AC_LANG_PROGRAM(
+                     [#include "cuda.h"],
+                       [CUresult r = cuCtxPushCurrent (NULL);])],
+                   [PLUGIN_NVPTX=1])
+                 CPPFLAGS=$PLUGIN_NVPTX_save_CPPFLAGS
+                 LDFLAGS=$PLUGIN_NVPTX_save_LDFLAGS
+                 LIBS=$PLUGIN_NVPTX_save_LIBS
+               fi
+               case $PLUGIN_NVPTX in
+                 nvptx*)
+                   if (test "x$CUDA_DRIVER_INCLUDE" = x \
+                       || test "x$CUDA_DRIVER_INCLUDE" = xno) \
+                      && (test "x$CUDA_DRIVER_LIB" = x \
+                          || test "x$CUDA_DRIVER_LIB" = xno); then
+                     PLUGIN_NVPTX=1
+                     PLUGIN_NVPTX_CPPFLAGS='-I$(srcdir)/plugin/cuda'
+                     PLUGIN_NVPTX_LIBS='-ldl'
+                     PLUGIN_NVPTX_DYNAMIC=1
+                   else
+                     PLUGIN_NVPTX=0
+                     AC_MSG_ERROR([CUDA driver package required for nvptx support])
+                   fi
+                   ;;
+               esac
+               ;;
+           esac
+           ;;
+         *-*-*)
+           # Target architecture not supported.
+           PLUGIN_NVPTX=0
+           ;;
        esac
        ;;
-
       amdgcn*)
        case "${target}" in
          x86_64-*-*)

diff --git a/libgomp/plugin/plugin-nvptx.c b/libgomp/plugin/plugin-nvptx.c
index 681c344b9c2cd94f70367c70c009c111e87a149f..1215212d501b5cb3dd99d39645370dc9cbeaf92a 100644 (file)
--- a/libgomp/plugin/plugin-nvptx.c
+++ b/libgomp/plugin/plugin-nvptx.c
@@ -572,15 +572,6 @@ nvptx_get_num_devices (void)
 {
   int n;
 
-  /* PR libgomp/65099: Currently, we only support offloading in 64-bit
-     configurations.  */
-  if (sizeof (void *) != 8)
-    {
-      GOMP_PLUGIN_debug (0, "Disabling nvptx offloading;"
-                        " only 64-bit configurations are supported\n");
-      return 0;
-    }
-
   /* This function will be called before the plugin has been initialized in
      order to enumerate available devices, but CUDA API routines can't be used
      until cuInit has been called.  Just call it now (but don't yet do any