Add '-Wopenacc-parallelism'

... to diagnose potentially suboptimal choices regarding OpenACC parallelism.

Not enabled by default: too noisy ("*potentially* suboptimal choices"); see
XFAILed 'dg-bogus'es.

	gcc/c-family/
	* c.opt (Wopenacc-parallelism): New.
	gcc/fortran/
	* lang.opt (Wopenacc-parallelism): New.
	gcc/
	* omp-offload.c (oacc_validate_dims): Implement
	'-Wopenacc-parallelism'.
	* doc/invoke.texi (-Wopenacc-parallelism): Document.
	gcc/testsuite/
	* c-c++-common/goacc/diag-parallelism-1.c: New.
	* c-c++-common/goacc/acc-icf.c: Specify '-Wopenacc-parallelism',
	and match diagnostics, as appropriate.
	* c-c++-common/goacc/classify-kernels-unparallelized.c: Likewise.
	* c-c++-common/goacc/classify-kernels.c: Likewise.
	* c-c++-common/goacc/classify-parallel.c: Likewise.
	* c-c++-common/goacc/classify-routine.c: Likewise.
	* c-c++-common/goacc/classify-serial.c: Likewise.
	* c-c++-common/goacc/kernels-decompose-1.c: Likewise.
	* c-c++-common/goacc/kernels-decompose-2.c: Likewise.
	* c-c++-common/goacc/parallel-dims-1.c: Likewise.
	* c-c++-common/goacc/parallel-reduction.c: Likewise.
	* c-c++-common/goacc/pr70688.c: Likewise.
	* c-c++-common/goacc/routine-1.c: Likewise.
	* c-c++-common/goacc/routine-level-of-parallelism-2.c: Likewise.
	* c-c++-common/goacc/uninit-dim-clause.c: Likewise.
	* gfortran.dg/goacc/classify-kernels-unparallelized.f95: Likewise.
	* gfortran.dg/goacc/classify-kernels.f95: Likewise.
	* gfortran.dg/goacc/classify-parallel.f95: Likewise.
	* gfortran.dg/goacc/classify-routine.f95: Likewise.
	* gfortran.dg/goacc/classify-serial.f95: Likewise.
	* gfortran.dg/goacc/kernels-decompose-1.f95: Likewise.
	* gfortran.dg/goacc/kernels-decompose-2.f95: Likewise.
	* gfortran.dg/goacc/parallel-tree.f95: Likewise.
	* gfortran.dg/goacc/routine-4.f90: Likewise.
	* gfortran.dg/goacc/routine-level-of-parallelism-1.f90: Likewise.
	* gfortran.dg/goacc/routine-module-mod-1.f90: Likewise.
	* gfortran.dg/goacc/routine-multiple-directives-1.f90: Likewise.
	* gfortran.dg/goacc/uninit-dim-clause.f95: Likewise.
	libgomp/
	* testsuite/libgomp.oacc-c-c++-common/firstprivate-1.c: Specify
	'-Wopenacc-parallelism', and match diagnostics, as appropriate.
	* testsuite/libgomp.oacc-c-c++-common/loop-auto-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/loop-red-w-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/loop-red-w-2.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/loop-w-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/mode-transitions.c:
	Likewise.
	* testsuite/libgomp.oacc-c-c++-common/par-reduction-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/par-reduction-2.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/parallel-dims.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/parallel-reduction.c:
	Likewise.
	* testsuite/libgomp.oacc-c-c++-common/pr85381-3.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/private-variables.c:
	Likewise.
	* testsuite/libgomp.oacc-c-c++-common/reduction-5.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/reduction-7.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/routine-g-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/routine-w-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/routine-wv-2.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/static-variable-1.c:
	Likewise.
	* testsuite/libgomp.oacc-fortran/optional-private.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/par-reduction-2-1.f: Likewise.
	* testsuite/libgomp.oacc-fortran/par-reduction-2-2.f: Likewise.
	* testsuite/libgomp.oacc-fortran/parallel-dims.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/parallel-reduction.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/pr84028.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/private-variables.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/reduction-1.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/reduction-5.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/reduction-6.f90: Likewise.
	* testsuite/libgomp.oacc-fortran/routine-7.f90: Likewise.

Co-Authored-By: Nathan Sidwell <nathan@codesourcery.com>
Co-Authored-By: Tom de Vries <vries@codesourcery.com>
Co-Authored-By: Julian Brown <julian@codesourcery.com>
Co-Authored-By: Kwok Cheung Yeung <kcy@codesourcery.com>

32 files changed, 302 insertions, 1 deletions

diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 3f8b72c..f1b4c3f 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -1037,6 +1037,10 @@ Wold-style-definition
 C ObjC Var(warn_old_style_definition) Init(-1) Warning
 Warn if an old-style parameter definition is used.
 
+Wopenacc-parallelism
+C C++ Var(warn_openacc_parallelism) Warning
+Warn about potentially suboptimal choices related to OpenACC parallelism.
+
 Wopenmp-simd
 C C++ Var(warn_openmp_simd) Warning LangEnabledBy(C C++,Wall)
 Warn if a simd directive is overridden by the vectorizer cost model.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index e98b096..40cacc6 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -364,7 +364,9 @@ Objective-C and Objective-C++ Dialects}.
 -Wmissing-include-dirs  -Wmissing-noreturn  -Wno-missing-profile @gol
 -Wno-multichar  -Wmultistatement-macros  -Wnonnull  -Wnonnull-compare @gol
 -Wnormalized=@r{[}none@r{|}id@r{|}nfc@r{|}nfkc@r{]} @gol
--Wnull-dereference  -Wno-odr  -Wopenmp-simd  @gol
+-Wnull-dereference  -Wno-odr  @gol
+-Wopenacc-parallelism  @gol
+-Wopenmp-simd  @gol
 -Wno-overflow  -Woverlength-strings  -Wno-override-init-side-effects @gol
 -Wpacked  -Wno-packed-bitfield-compat  -Wpacked-not-aligned  -Wpadded @gol
 -Wparentheses  -Wno-pedantic-ms-format @gol
@@ -8749,6 +8751,12 @@ Do not warn about compile-time overflow in constant expressions.
 Warn about One Definition Rule violations during link-time optimization.
 Enabled by default.
 
+@item -Wopenacc-parallelism
+@opindex Wopenacc-parallelism
+@opindex Wno-openacc-parallelism
+@cindex OpenACC accelerator programming
+Warn about potentially suboptimal choices related to OpenACC parallelism.
+
 @item -Wopenmp-simd
 @opindex Wopenmp-simd
 @opindex Wno-openmp-simd
diff --git a/gcc/fortran/lang.opt b/gcc/fortran/lang.opt
index 388ef8c..6db01c7 100644
--- a/gcc/fortran/lang.opt
+++ b/gcc/fortran/lang.opt
@@ -285,6 +285,10 @@ Wuse-without-only
 Fortran Var(warn_use_without_only) Warning
 Warn about USE statements that have no ONLY qualifier.
 
+Wopenacc-parallelism
+Fortran
+; Documented in C
+
 Wopenmp-simd
 Fortran
 ; Documented in C
diff --git a/gcc/omp-offload.c b/gcc/omp-offload.c
index ba0937f..1612461 100644
--- a/gcc/omp-offload.c
+++ b/gcc/omp-offload.c
@@ -928,6 +928,35 @@ oacc_validate_dims (tree fn, tree attrs, int *dims, int level, unsigned used)
       pos = TREE_CHAIN (pos);
     }
 
+  bool check = true;
+#ifdef ACCEL_COMPILER
+  check = false;
+#endif
+  if (check
+      && warn_openacc_parallelism
+      && !lookup_attribute ("oacc kernels", DECL_ATTRIBUTES (fn)))
+    {
+      static char const *const axes[] =
+      /* Must be kept in sync with GOMP_DIM enumeration.  */
+	{ "gang", "worker", "vector" };
+      for (ix = level >= 0 ? level : 0; ix != GOMP_DIM_MAX; ix++)
+	if (dims[ix] < 0)
+	  ; /* Defaulting axis.  */
+	else if ((used & GOMP_DIM_MASK (ix)) && dims[ix] == 1)
+	  /* There is partitioned execution, but the user requested a
+	     dimension size of 1.  They're probably confused.  */
+	  warning_at (DECL_SOURCE_LOCATION (fn), OPT_Wopenacc_parallelism,
+		      "region contains %s partitioned code but"
+		      " is not %s partitioned", axes[ix], axes[ix]);
+	else if (!(used & GOMP_DIM_MASK (ix)) && dims[ix] != 1)
+	  /* The dimension is explicitly partitioned to non-unity, but
+	     no use is made within the region.  */
+	  warning_at (DECL_SOURCE_LOCATION (fn), OPT_Wopenacc_parallelism,
+		      "region is %s partitioned but"
+		      " does not contain %s partitioned code",
+		      axes[ix], axes[ix]);
+    }
+
   bool changed = targetm.goacc.validate_dims (fn, dims, level, used);
 
   /* Default anything left to 1 or a partitioned default.  */
diff --git a/gcc/testsuite/c-c++-common/goacc/acc-icf.c b/gcc/testsuite/c-c++-common/goacc/acc-icf.c
index 98b536c..9cf119b 100644
--- a/gcc/testsuite/c-c++-common/goacc/acc-icf.c
+++ b/gcc/testsuite/c-c++-common/goacc/acc-icf.c
@@ -2,7 +2,12 @@
 
 /* { dg-additional-options "-fopenacc -O2 -fdump-ipa-icf" }  */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #pragma acc routine gang
+/* { dg-bogus "warning: region is worker partitioned but does not contain worker partitioned code" "TODO default 'gang' 'vector'" { xfail *-*-* } .+3 }
+   TODO It's the compiler's own decision to not use 'worker' parallelism here, so it doesn't make sense to bother the user about it.  */
 int
 routine1 (int n)
 {
@@ -16,6 +21,8 @@ routine1 (int n)
 }
 
 #pragma acc routine gang
+/* { dg-bogus "warning: region is worker partitioned but does not contain worker partitioned code" "TODO default 'gang' 'vector'" { xfail *-*-* } .+3 }
+   TODO It's the compiler's own decision to not use 'worker' parallelism here, so it doesn't make sense to bother the user about it.  */
 int
 routine2 (int n)
 {
diff --git a/gcc/testsuite/c-c++-common/goacc/classify-kernels-unparallelized.c b/gcc/testsuite/c-c++-common/goacc/classify-kernels-unparallelized.c
index d4c4b2c..218f624 100644
--- a/gcc/testsuite/c-c++-common/goacc/classify-kernels-unparallelized.c
+++ b/gcc/testsuite/c-c++-common/goacc/classify-kernels-unparallelized.c
@@ -7,6 +7,9 @@
    { dg-additional-options "-fdump-tree-parloops1-all" }
    { dg-additional-options "-fdump-tree-oaccdevlow" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #define N 1024
 
 extern unsigned int *__restrict a;
diff --git a/gcc/testsuite/c-c++-common/goacc/classify-kernels.c b/gcc/testsuite/c-c++-common/goacc/classify-kernels.c
index 16e9b9e..95a150c 100644
--- a/gcc/testsuite/c-c++-common/goacc/classify-kernels.c
+++ b/gcc/testsuite/c-c++-common/goacc/classify-kernels.c
@@ -7,6 +7,9 @@
    { dg-additional-options "-fdump-tree-parloops1-all" }
    { dg-additional-options "-fdump-tree-oaccdevlow" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #define N 1024
 
 extern unsigned int *__restrict a;
diff --git a/gcc/testsuite/c-c++-common/goacc/classify-parallel.c b/gcc/testsuite/c-c++-common/goacc/classify-parallel.c
index 933d766..230e70c 100644
--- a/gcc/testsuite/c-c++-common/goacc/classify-parallel.c
+++ b/gcc/testsuite/c-c++-common/goacc/classify-parallel.c
@@ -6,6 +6,9 @@
    { dg-additional-options "-fdump-tree-ompexp" }
    { dg-additional-options "-fdump-tree-oaccdevlow" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #define N 1024
 
 extern unsigned int *__restrict a;
diff --git a/gcc/testsuite/c-c++-common/goacc/classify-routine.c b/gcc/testsuite/c-c++-common/goacc/classify-routine.c
index 0b9ba6e..81fe369 100644
--- a/gcc/testsuite/c-c++-common/goacc/classify-routine.c
+++ b/gcc/testsuite/c-c++-common/goacc/classify-routine.c
@@ -6,6 +6,9 @@
    { dg-additional-options "-fdump-tree-ompexp" }
    { dg-additional-options "-fdump-tree-oaccdevlow" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #define N 1024
 
 extern unsigned int *__restrict a;
diff --git a/gcc/testsuite/c-c++-common/goacc/classify-serial.c b/gcc/testsuite/c-c++-common/goacc/classify-serial.c
index 94ace1b..ae052ae 100644
--- a/gcc/testsuite/c-c++-common/goacc/classify-serial.c
+++ b/gcc/testsuite/c-c++-common/goacc/classify-serial.c
@@ -6,6 +6,9 @@
    { dg-additional-options "-fdump-tree-ompexp" }
    { dg-additional-options "-fdump-tree-oaccdevlow" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #define N 1024
 
 extern unsigned int *__restrict a;
@@ -15,6 +18,11 @@ extern unsigned int *__restrict c;
 void SERIAL ()
 {
 #pragma acc serial loop copyin (a[0:N], b[0:N]) copyout (c[0:N]) /* { dg-message "optimized: assigned OpenACC gang vector loop parallelism" } */
+  /* { dg-bogus "warning: region contains gang partitioned code but is not gang partitioned" "TODO 'serial'" { xfail *-*-* } .-1 }
+     { dg-bogus "warning: region contains worker partitioned code but is not worker partitioned" "" { target *-*-* } .-2 }
+     { dg-bogus "warning: region contains vector partitioned code but is not vector partitioned" "TODO 'serial'" { xfail *-*-* } .-3 }
+     TODO Should we really diagnose this if the user explicitly requested 'serial'?
+     TODO Should we instead diagnose ('-Wextra' category?) that the user may enable use of parallelism if replacing 'serial' with 'parallel', if applicable?  */
   for (unsigned int i = 0; i < N; i++)
     c[i] = a[i] + b[i];
 }
diff --git a/gcc/testsuite/c-c++-common/goacc/diag-parallelism-1.c b/gcc/testsuite/c-c++-common/goacc/diag-parallelism-1.c
new file mode 100644
index 0000000..6ee7bd0
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/diag-parallelism-1.c
@@ -0,0 +1,124 @@
+/* Diagnostics about potentially suboptimal choices related to OpenACC
+   parallelism.
+
+   { dg-additional-options "-Wopenacc-parallelism" }
+*/
+
+
+//TODO 'kernels'
+
+//TODO 'serial'
+
+//TODO 'routine'
+
+//TODO Fortran
+
+
+static void f1 ()
+{
+  int ary[10];
+
+
+#pragma acc parallel num_gangs (1)
+  /* { dg-warning "region contains gang partitioned code but is not gang partitioned" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop gang
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel num_workers (1)
+  /* { dg-warning "region contains worker partitioned code but is not worker partitioned" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop worker
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel vector_length (1)
+  /* { dg-warning "region contains vector partitioned code but is not vector partitioned" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop vector
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+}
+
+
+static void f2 ()
+{
+  int ary[10];
+
+
+#pragma acc parallel num_gangs (8)
+  /* { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop worker
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel num_gangs (8)
+  /* { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop vector
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel num_gangs (8)
+  /* { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop worker vector
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel num_workers (8)
+  /* { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop gang
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel num_workers (8)
+  /* { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop vector
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel num_workers (8)
+  /* { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop gang vector
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel vector_length (8)
+  /* { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop gang
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel vector_length (8)
+  /* { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop worker
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+
+#pragma acc parallel vector_length (8)
+  /* { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-1 } */
+  {
+    #pragma acc loop gang worker
+    for (int i = 0; i < 10; i++)
+      ary[i] = i;
+  }
+}
diff --git a/gcc/testsuite/c-c++-common/goacc/kernels-decompose-1.c b/gcc/testsuite/c-c++-common/goacc/kernels-decompose-1.c
index 87219c8..f549cba 100644
--- a/gcc/testsuite/c-c++-common/goacc/kernels-decompose-1.c
+++ b/gcc/testsuite/c-c++-common/goacc/kernels-decompose-1.c
@@ -5,6 +5,9 @@
 /* { dg-additional-options "--param=openacc-kernels=decompose" }
    { dg-additional-options "-fdump-tree-omp_oacc_kernels_decompose" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 /* See also '../../gfortran.dg/goacc/kernels-decompose-1.f95'.  */
 
 /* It's only with Tcl 8.5 (released in 2007) that "the variable 'varName'
diff --git a/gcc/testsuite/c-c++-common/goacc/kernels-decompose-2.c b/gcc/testsuite/c-c++-common/goacc/kernels-decompose-2.c
index 3781e75..cdf85d4 100644
--- a/gcc/testsuite/c-c++-common/goacc/kernels-decompose-2.c
+++ b/gcc/testsuite/c-c++-common/goacc/kernels-decompose-2.c
@@ -4,6 +4,9 @@
 /* { dg-additional-options "--param=openacc-kernels=decompose" }
 /* { dg-additional-options "-O2" } for 'parloops'.  */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 /* See also '../../gfortran.dg/goacc/kernels-decompose-2.f95'.  */
 
 /* It's only with Tcl 8.5 (released in 2007) that "the variable 'varName'
@@ -116,6 +119,7 @@ main ()
   }
 
 #pragma acc kernels
+  /* { dg-bogus "warning: region contains gang partitioned code but is not gang partitioned" "TODO 'kernels'" { xfail *-*-* } .-1 } */
   {
     y = f_g (a[5]); /* { dg-line l_part[incr c_part] } */
     /*TODO If such a construct is placed in its own part (like it is, here), can't this actually use gang paralelism, instead of "gang-single"?
diff --git a/gcc/testsuite/c-c++-common/goacc/parallel-dims-1.c b/gcc/testsuite/c-c++-common/goacc/parallel-dims-1.c
index 57f682f..2a8d35d 100644
--- a/gcc/testsuite/c-c++-common/goacc/parallel-dims-1.c
+++ b/gcc/testsuite/c-c++-common/goacc/parallel-dims-1.c
@@ -1,11 +1,18 @@
 /* Valid use of OpenACC parallelism dimensions clauses: num_gangs, num_workers,
    vector_length.  */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 void f(int i)
 {
 #pragma acc kernels num_gangs(i) num_workers(i) vector_length(i)
   ;
 
 #pragma acc parallel num_gangs(i) num_workers(i) vector_length(i)
+  /* { dg-bogus "warning: region is gang partitioned but does not contain gang partitioned code" "TODO runtime" { xfail *-*-* } .-1 }
+     { dg-bogus "warning: region is worker partitioned but does not contain worker partitioned code" "TODO runtime" { xfail *-*-* } .-2 }
+     { dg-bogus "warning: region is vector partitioned but does not contain vector partitioned code" "TODO runtime" { xfail *-*-* } .-3 }
+     TODO 'region is [...] partitioned' isn't correct for 'i == 1'.  */
   ;
 }
diff --git a/gcc/testsuite/c-c++-common/goacc/parallel-reduction.c b/gcc/testsuite/c-c++-common/goacc/parallel-reduction.c
index d7cc947..c5c0edc 100644
--- a/gcc/testsuite/c-c++-common/goacc/parallel-reduction.c
+++ b/gcc/testsuite/c-c++-common/goacc/parallel-reduction.c
@@ -1,3 +1,6 @@
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 int
 main ()
 {
@@ -7,6 +10,7 @@ main ()
 #pragma acc data copy (dummy)
   {
 #pragma acc parallel num_gangs (10) copy (sum) reduction (+:sum)
+    /* { dg-bogus "warning: region is gang partitioned but does not contain gang partitioned code" "TODO 'reduction'" { xfail *-*-* } .-1 } */
     {
       int v = 5;
       sum += 10 + v;
diff --git a/gcc/testsuite/c-c++-common/goacc/pr70688.c b/gcc/testsuite/c-c++-common/goacc/pr70688.c
index 5a23665..e96a853 100644
--- a/gcc/testsuite/c-c++-common/goacc/pr70688.c
+++ b/gcc/testsuite/c-c++-common/goacc/pr70688.c
@@ -1,3 +1,6 @@
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 const int n = 100;
 
 int
@@ -22,6 +25,7 @@ parallel_reduction ()
 #pragma acc data copy (dummy)
   {
 #pragma acc parallel num_gangs (10) copy (sum) reduction (+:sum)
+    /* { dg-bogus "warning: region is gang partitioned but does not contain gang partitioned code" "TODO 'reduction'" { xfail *-*-* } .-1 } */
     {
       int v = 5;
       sum += 10 + v;
@@ -37,10 +41,12 @@ main ()
   int i, s = 0;
 
 #pragma acc parallel num_gangs (10) copy (s) reduction (+:s)
+  /* { dg-bogus "warning: region is gang partitioned but does not contain gang partitioned code" "TODO 'reduction'" { xfail *-*-* } .-1 } */
   for (i = 0; i < n; i++)
     s += i+1;
 
 #pragma acc parallel num_gangs (10) reduction (+:s) copy (s)
+  /* { dg-bogus "warning: region is gang partitioned but does not contain gang partitioned code" "TODO 'reduction'" { xfail *-*-* } .-1 } */
   for (i = 0; i < n; i++)
     s += i+1;
 
diff --git a/gcc/testsuite/c-c++-common/goacc/routine-1.c b/gcc/testsuite/c-c++-common/goacc/routine-1.c
index a756922..051f793 100644
--- a/gcc/testsuite/c-c++-common/goacc/routine-1.c
+++ b/gcc/testsuite/c-c++-common/goacc/routine-1.c
@@ -1,15 +1,23 @@
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
 
 #pragma acc routine gang
+/* { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .+3 }
+   { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .+2 }
+   { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .+1 } */
 void gang (void)
 {
 }
 
 #pragma acc routine worker
+/* { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .+2 }
+   { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .+1 } */
 void worker (void)
 {
 }
 
 #pragma acc routine vector
+/* { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .+1 } */
 void vector (void)
 {
 }
diff --git a/gcc/testsuite/c-c++-common/goacc/routine-level-of-parallelism-2.c b/gcc/testsuite/c-c++-common/goacc/routine-level-of-parallelism-2.c
index a066f2b..33678fe 100644
--- a/gcc/testsuite/c-c++-common/goacc/routine-level-of-parallelism-2.c
+++ b/gcc/testsuite/c-c++-common/goacc/routine-level-of-parallelism-2.c
@@ -2,7 +2,13 @@
    with the OpenACC 'routine' directive.  The Fortran counterpart is
    '../../gfortran.dg/goacc/routine-level-of-parallelism-1.f90'.  */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 #pragma acc routine gang
+/* { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .+3 }
+   { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .+2 }
+   { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .+1 } */
 void g_1 (void)
 {
 }
diff --git a/gcc/testsuite/c-c++-common/goacc/uninit-dim-clause.c b/gcc/testsuite/c-c++-common/goacc/uninit-dim-clause.c
index 827dac7..d9b143b 100644
--- a/gcc/testsuite/c-c++-common/goacc/uninit-dim-clause.c
+++ b/gcc/testsuite/c-c++-common/goacc/uninit-dim-clause.c
@@ -1,16 +1,22 @@
 /* { dg-additional-options "-Wuninitialized" } */
 
+/* { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+   aspects of that functionality.  */
+
 void acc_parallel()
 {
   int i, j, k;
 
   #pragma acc parallel num_gangs(i) /* { dg-warning "is used uninitialized" } */
+  /* { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-1 } */
   ;
 
   #pragma acc parallel num_workers(j) /* { dg-warning "is used uninitialized" } */
+  /* { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-1 } */
   ;
 
   #pragma acc parallel vector_length(k) /* { dg-warning "is used uninitialized" } */
+  /* { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-1 } */
   ;
 }
 
diff --git a/gcc/testsuite/gfortran.dg/goacc/classify-kernels-unparallelized.f95 b/gcc/testsuite/gfortran.dg/goacc/classify-kernels-unparallelized.f95
index 6cca3d6..cb5251a 100644
--- a/gcc/testsuite/gfortran.dg/goacc/classify-kernels-unparallelized.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/classify-kernels-unparallelized.f95
@@ -7,6 +7,9 @@
 ! { dg-additional-options "-fdump-tree-parloops1-all" }
 ! { dg-additional-options "-fdump-tree-oaccdevlow" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 program main
   implicit none
   integer, parameter :: n = 1024
diff --git a/gcc/testsuite/gfortran.dg/goacc/classify-kernels.f95 b/gcc/testsuite/gfortran.dg/goacc/classify-kernels.f95
index 715a983..07aaf06 100644
--- a/gcc/testsuite/gfortran.dg/goacc/classify-kernels.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/classify-kernels.f95
@@ -7,6 +7,9 @@
 ! { dg-additional-options "-fdump-tree-parloops1-all" }
 ! { dg-additional-options "-fdump-tree-oaccdevlow" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 program main
   implicit none
   integer, parameter :: n = 1024
diff --git a/gcc/testsuite/gfortran.dg/goacc/classify-parallel.f95 b/gcc/testsuite/gfortran.dg/goacc/classify-parallel.f95
index 01f06bb..a41e0e6 100644
--- a/gcc/testsuite/gfortran.dg/goacc/classify-parallel.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/classify-parallel.f95
@@ -6,6 +6,9 @@
 ! { dg-additional-options "-fdump-tree-ompexp" }
 ! { dg-additional-options "-fdump-tree-oaccdevlow" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 program main
   implicit none
   integer, parameter :: n = 1024
diff --git a/gcc/testsuite/gfortran.dg/goacc/classify-routine.f95 b/gcc/testsuite/gfortran.dg/goacc/classify-routine.f95
index 401d527..52cc870 100644
--- a/gcc/testsuite/gfortran.dg/goacc/classify-routine.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/classify-routine.f95
@@ -6,6 +6,9 @@
 ! { dg-additional-options "-fdump-tree-ompexp" }
 ! { dg-additional-options "-fdump-tree-oaccdevlow" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 subroutine ROUTINE
   !$acc routine worker
   integer, parameter :: n = 1024
diff --git a/gcc/testsuite/gfortran.dg/goacc/classify-serial.f95 b/gcc/testsuite/gfortran.dg/goacc/classify-serial.f95
index 51061af..6d402e6 100644
--- a/gcc/testsuite/gfortran.dg/goacc/classify-serial.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/classify-serial.f95
@@ -6,6 +6,9 @@
 ! { dg-additional-options "-fdump-tree-ompexp" }
 ! { dg-additional-options "-fdump-tree-oaccdevlow" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 program main
   implicit none
   integer, parameter :: n = 1024
@@ -15,6 +18,9 @@ program main
   call setup(a, b)
 
   !$acc serial loop copyin (a(0:n-1), b(0:n-1)) copyout (c(0:n-1)) ! { dg-message "optimized: assigned OpenACC gang vector loop parallelism" }
+  ! { dg-bogus "warning: region contains gang partitioned code but is not gang partitioned" "TODO 'serial'" { xfail *-*-* } .-1 }
+  ! { dg-bogus "warning: region contains worker partitioned code but is not worker partitioned" "" { target *-*-* } .-2 }
+  ! { dg-bogus "warning: region contains vector partitioned code but is not vector partitioned" "TODO 'serial'" { xfail *-*-* } .-3 }
   do i = 0, n - 1
      c(i) = a(i) + b(i)
   end do
diff --git a/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-1.f95 b/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-1.f95
index e252350..ddaf7f8 100644
--- a/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-1.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-1.f95
@@ -5,6 +5,9 @@
 ! { dg-additional-options "--param=openacc-kernels=decompose" }
 ! { dg-additional-options "-fdump-tree-omp_oacc_kernels_decompose" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 ! See also '../../c-c++-common/goacc/kernels-decompose-1.c'.
 
 ! It's only with Tcl 8.5 (released in 2007) that "the variable 'varName'
diff --git a/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-2.f95 b/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-2.f95
index cc12b77..a3cec83 100644
--- a/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-2.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/kernels-decompose-2.f95
@@ -4,6 +4,9 @@
 ! { dg-additional-options "--param=openacc-kernels=decompose" }
 ! { dg-additional-options "-O2" } for 'parloops'.
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 ! See also '../../c-c++-common/goacc/kernels-decompose-2.c'.
 
 ! It's only with Tcl 8.5 (released in 2007) that "the variable 'varName'
@@ -119,6 +122,7 @@ program main
   !$acc end kernels
 
   !$acc kernels
+  ! { dg-bogus "warning: region contains gang partitioned code but is not gang partitioned" "TODO 'kernels'" { xfail *-*-* } .-1 }
   y = f_g (a(5)) ! { dg-line l_part[incr c_part] }
   !TODO If such a construct is placed in its own part (like it is, here), can't this actually use gang paralelism, instead of "gang-single"?
   ! { dg-message "note: beginning 'gang-single' part in OpenACC 'kernels' region" "" { target *-*-* } l_part$c_part }
diff --git a/gcc/testsuite/gfortran.dg/goacc/parallel-tree.f95 b/gcc/testsuite/gfortran.dg/goacc/parallel-tree.f95
index e33653b..c51cb2a 100644
--- a/gcc/testsuite/gfortran.dg/goacc/parallel-tree.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/parallel-tree.f95
@@ -2,6 +2,9 @@
 
 ! test for tree-dump-original and spaces-commas
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 program test
   implicit none
   integer :: q, i, j, k, m, n, o, p, r, s, t, u, v, w
@@ -12,6 +15,9 @@ program test
   !$acc no_create(n) &
   !$acc present(o), pcopy(p), pcopyin(r), pcopyout(s), pcreate(t) &
   !$acc deviceptr(u), private(v), firstprivate(w)
+  ! { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-1 }
+  ! { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-2 }
+  ! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-3 }
   !$acc end parallel
 
 end program test
diff --git a/gcc/testsuite/gfortran.dg/goacc/routine-4.f90 b/gcc/testsuite/gfortran.dg/goacc/routine-4.f90
index 6714c7b..53b1fbe 100644
--- a/gcc/testsuite/gfortran.dg/goacc/routine-4.f90
+++ b/gcc/testsuite/gfortran.dg/goacc/routine-4.f90
@@ -1,5 +1,8 @@
 ! Test invalid calls to routines.
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 module param
   integer, parameter :: N = 32
 end module param
@@ -120,6 +123,9 @@ contains
 
   subroutine gang (a) ! { dg-message "declared here" 3 }
     !$acc routine gang
+    ! { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-2 }
+    ! { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-3 }
+    ! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-4 }
     integer, intent (inout) :: a(N)
     integer :: i
 
@@ -130,6 +136,8 @@ contains
 
   subroutine worker (a) ! { dg-message "declared here" 2 }
     !$acc routine worker
+    ! { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-2 }
+    ! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-3 }
     integer, intent (inout) :: a(N)
     integer :: i
 
@@ -140,6 +148,7 @@ contains
 
   subroutine vector (a) ! { dg-message "declared here" }
     !$acc routine vector
+    ! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-2 }
     integer, intent (inout) :: a(N)
     integer :: i
 
diff --git a/gcc/testsuite/gfortran.dg/goacc/routine-level-of-parallelism-1.f90 b/gcc/testsuite/gfortran.dg/goacc/routine-level-of-parallelism-1.f90
index 83b8c24..99929f1 100644
--- a/gcc/testsuite/gfortran.dg/goacc/routine-level-of-parallelism-1.f90
+++ b/gcc/testsuite/gfortran.dg/goacc/routine-level-of-parallelism-1.f90
@@ -2,8 +2,14 @@
 ! with the OpenACC routine directive.  The C/C++ counterpart is
 ! '../../c-c++-common/goacc/routine-level-of-parallelism-2.c'.
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 subroutine g_1
   !$acc routine gang
+  ! { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-2 }
+  ! { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-3 }
+  ! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-4 }
 end subroutine g_1
 
 subroutine s_1_2a
diff --git a/gcc/testsuite/gfortran.dg/goacc/routine-module-mod-1.f90 b/gcc/testsuite/gfortran.dg/goacc/routine-module-mod-1.f90
index 23c673f..2210650 100644
--- a/gcc/testsuite/gfortran.dg/goacc/routine-module-mod-1.f90
+++ b/gcc/testsuite/gfortran.dg/goacc/routine-module-mod-1.f90
@@ -2,6 +2,9 @@
 
 ! { dg-additional-options "-fopt-info-optimized-omp" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 module routine_module_mod_1
 contains
   subroutine s_1
@@ -53,6 +56,7 @@ contains
   subroutine g_1
     implicit none
     !$acc routine gang
+    ! { dg-bogus "warning: region is worker partitioned but does not contain worker partitioned code" "TODO default 'gang' 'vector'" { xfail *-*-* } .-3 }
 
     integer :: i
 
diff --git a/gcc/testsuite/gfortran.dg/goacc/routine-multiple-directives-1.f90 b/gcc/testsuite/gfortran.dg/goacc/routine-multiple-directives-1.f90
index 6e12ee9..622a9d9 100644
--- a/gcc/testsuite/gfortran.dg/goacc/routine-multiple-directives-1.f90
+++ b/gcc/testsuite/gfortran.dg/goacc/routine-multiple-directives-1.f90
@@ -1,5 +1,8 @@
 ! Check for valid cases of multiple OpenACC 'routine' directives.
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
       SUBROUTINE s_1
 !$ACC ROUTINE(s_1)
 !$ACC ROUTINE(s_1) SEQ
@@ -17,12 +20,14 @@
 !$ACC ROUTINE VECTOR
 !$ACC ROUTINE(v_1) VECTOR
 !$ACC ROUTINE VECTOR
+! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-5 }
       END SUBROUTINE v_1
 
       SUBROUTINE v_2
 !$ACC ROUTINE(v_2) VECTOR
 !$ACC ROUTINE VECTOR
 !$ACC ROUTINE(v_2) VECTOR
+! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-4 }
       END SUBROUTINE v_2
 
       SUBROUTINE sub_1
diff --git a/gcc/testsuite/gfortran.dg/goacc/uninit-dim-clause.f95 b/gcc/testsuite/gfortran.dg/goacc/uninit-dim-clause.f95
index c77d47a..59e923f 100644
--- a/gcc/testsuite/gfortran.dg/goacc/uninit-dim-clause.f95
+++ b/gcc/testsuite/gfortran.dg/goacc/uninit-dim-clause.f95
@@ -1,16 +1,22 @@
 ! { dg-additional-options "-Wuninitialized" }
 
+! { dg-additional-options "-Wopenacc-parallelism" } for testing/documenting
+! aspects of that functionality.
+
 subroutine acc_parallel
   implicit none
   integer :: i, j, k
 
   !$acc parallel num_gangs(i) ! { dg-warning "is used uninitialized" }
+  ! { dg-warning "region is gang partitioned but does not contain gang partitioned code" "" { target *-*-* } .-1 }
   !$acc end parallel
 
   !$acc parallel num_workers(j) ! { dg-warning "is used uninitialized" }
+  ! { dg-warning "region is worker partitioned but does not contain worker partitioned code" "" { target *-*-* } .-1 }
   !$acc end parallel
 
   !$acc parallel vector_length(k) ! { dg-warning "is used uninitialized" }
+  ! { dg-warning "region is vector partitioned but does not contain vector partitioned code" "" { target *-*-* } .-1 }
   !$acc end parallel
 end subroutine acc_parallel