Re: [committed] Fix OpenMP parsing of the specification part in functions (PR fortran/71704)

[Cesar Philippidis <cesar at codesourcery dot com>]

On 07/08/2016 09:18 AM, Jakub Jelinek wrote:
> On Fri, Jul 08, 2016 at 09:13:50AM -0700, Cesar Philippidis wrote:
>> On 06/30/2016 10:47 AM, Jakub Jelinek wrote:
>>
>>> The Fortran parser apparently relies in functions that have still undecided
>>> kind of the result that ST_GET_FCN_CHARACTERISTICS artificial statement is
>>> returned before any executable statements in the function.
>>> In normal statements that is ensured through decode_statement calling
>>> decode_specification_statement, which parses just a subset of statements,
>>> but for OpenMP we need to do something similar.  If we figure out we want
>>> only the case_omp_decl statements, for any other we just try to gfc_match
>>> the keyword and if we match it, it means we'd be about to return an OpenMP
>>> executable statement, so instead return ST_GET_FCN_CHARACTERISTICS.
>>>
>>> Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk,
>>> queued for 6.2 backport.
>>>
>>> Cesar, note OpenACC will need something similar (though,
>>> decode_acc_statement uses just the match macro, so you'll need another one
>>> for the executable statements).
>>
>> Here's the OpenACC followup for this patch. Is it OK for trunk and gcc6?
> 
> ENOPATCH

Sorry!

Cesar

2016-07-08  Cesar Philippidis  <cesar@codesourcery.com>

	gcc/fortran/
	* parse.c (matcha): Define.
	(decode_oacc_directive): Add spec_only local var and set it.  Use
	matcha to parse acc data, enter data, exit data, host_data, parallel,
	kernels, update and wait directives.  Return ST_GET_FCN_CHARACTERISTICS
	if a non-declarative directive could be matched.

	gcc/testsuite/
	* gfortran.dg/goacc/pr71704-acc.f90: New test.


diff --git a/gcc/fortran/parse.c b/gcc/fortran/parse.c
index d795225..b1d9c00 100644
--- a/gcc/fortran/parse.c
+++ b/gcc/fortran/parse.c
@@ -589,11 +589,25 @@ decode_statement (void)
   return ST_NONE;
 }
 
+/* Like match, but don't match anything if not -fopenacc
+   and if spec_only, goto do_spec_only without actually matching.  */
+#define matcha(keyword, subr, st)				\
+    do {							\
+      if (spec_only && gfc_match (keyword) == MATCH_YES)	\
+	goto do_spec_only;					\
+      else if (match_word (keyword, subr, &old_locus)		\
+	       == MATCH_YES)					\
+	return st;						\
+      else							\
+	undo_new_statement ();				  	\
+    } while (0);
+
 static gfc_statement
 decode_oacc_directive (void)
 {
   locus old_locus;
   char c;
+  bool spec_only = false;
 
   gfc_enforce_clean_symbol_state ();
 
@@ -608,6 +622,10 @@ decode_oacc_directive (void)
       return ST_NONE;
     }
 
+  if (gfc_current_state () == COMP_FUNCTION
+      && gfc_current_block ()->result->ts.kind == -1)
+    spec_only = true;
+
   gfc_unset_implicit_pure (NULL);
 
   old_locus = gfc_current_locus;
@@ -627,7 +645,7 @@ decode_oacc_directive (void)
       match ("cache", gfc_match_oacc_cache, ST_OACC_CACHE);
       break;
     case 'd':
-      match ("data", gfc_match_oacc_data, ST_OACC_DATA);
+      matcha ("data", gfc_match_oacc_data, ST_OACC_DATA);
       match ("declare", gfc_match_oacc_declare, ST_OACC_DECLARE);
       break;
     case 'e':
@@ -639,19 +657,19 @@ decode_oacc_directive (void)
       match ("end loop", gfc_match_omp_eos, ST_OACC_END_LOOP);
       match ("end parallel loop", gfc_match_omp_eos, ST_OACC_END_PARALLEL_LOOP);
       match ("end parallel", gfc_match_omp_eos, ST_OACC_END_PARALLEL);
-      match ("enter data", gfc_match_oacc_enter_data, ST_OACC_ENTER_DATA);
-      match ("exit data", gfc_match_oacc_exit_data, ST_OACC_EXIT_DATA);
+      matcha ("enter data", gfc_match_oacc_enter_data, ST_OACC_ENTER_DATA);
+      matcha ("exit data", gfc_match_oacc_exit_data, ST_OACC_EXIT_DATA);
       break;
     case 'h':
-      match ("host_data", gfc_match_oacc_host_data, ST_OACC_HOST_DATA);
+      matcha ("host_data", gfc_match_oacc_host_data, ST_OACC_HOST_DATA);
       break;
     case 'p':
       match ("parallel loop", gfc_match_oacc_parallel_loop, ST_OACC_PARALLEL_LOOP);
-      match ("parallel", gfc_match_oacc_parallel, ST_OACC_PARALLEL);
+      matcha ("parallel", gfc_match_oacc_parallel, ST_OACC_PARALLEL);
       break;
     case 'k':
       match ("kernels loop", gfc_match_oacc_kernels_loop, ST_OACC_KERNELS_LOOP);
-      match ("kernels", gfc_match_oacc_kernels, ST_OACC_KERNELS);
+      matcha ("kernels", gfc_match_oacc_kernels, ST_OACC_KERNELS);
       break;
     case 'l':
       match ("loop", gfc_match_oacc_loop, ST_OACC_LOOP);
@@ -660,10 +678,10 @@ decode_oacc_directive (void)
       match ("routine", gfc_match_oacc_routine, ST_OACC_ROUTINE);
       break;
     case 'u':
-      match ("update", gfc_match_oacc_update, ST_OACC_UPDATE);
+      matcha ("update", gfc_match_oacc_update, ST_OACC_UPDATE);
       break;
     case 'w':
-      match ("wait", gfc_match_oacc_wait, ST_OACC_WAIT);
+      matcha ("wait", gfc_match_oacc_wait, ST_OACC_WAIT);
       break;
     }
 
@@ -678,6 +696,13 @@ decode_oacc_directive (void)
   gfc_error_recovery ();
 
   return ST_NONE;
+
+ do_spec_only:
+  reject_statement ();
+  gfc_clear_error ();
+  gfc_buffer_error (false);
+  gfc_current_locus = old_locus;
+  return ST_GET_FCN_CHARACTERISTICS;
 }
 
 /* Like match, but set a flag simd_matched if keyword matched
diff --git a/gcc/testsuite/gfortran.dg/goacc/pr71704-acc.f90 b/gcc/testsuite/gfortran.dg/goacc/pr71704-acc.f90
new file mode 100644
index 0000000..0235e85
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/goacc/pr71704-acc.f90
@@ -0,0 +1,60 @@
+! PR fortran/71704
+! { dg-do compile }
+
+real function f1 ()
+!$acc routine (f1)
+  f1 = 1
+end
+
+real function f2 (a)
+  integer a
+  !$acc enter data copyin(a)
+  f2 = 1
+end
+
+real function f3 (a)
+  integer a
+!$acc enter data copyin(a)
+  f3 = 1
+end
+
+real function f4 ()
+!$acc wait
+  f4 = 1
+end
+
+real function f5 (a)
+  integer a
+!$acc update device(a)
+  f5 = 1
+end
+
+real function f6 ()
+!$acc parallel
+!$acc end parallel
+  f6 = 1
+end
+
+real function f7 ()
+!$acc kernels
+!$acc end kernels
+  f7 = 1
+end
+
+real function f8 ()
+!$acc data
+!$acc end data
+  f8 = 1
+end
+
+real function f9 ()
+!$acc host_data
+!$acc end host_data
+  f8 = 1
+end
+
+real function f10 (a)
+  integer a
+!$acc declare present (a)
+  f8 = 1
+end