Handle BUILT_IN_GOMP_PARALLEL in ipa-pta

2015-11-30  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/46032
	* tree-ssa-structalias.c (find_func_aliases_for_call_arg): New function,
	factored out of ...
	(find_func_aliases_for_call): ... here.
	(find_func_aliases_for_builtin_call, find_func_clobbers): Handle
	BUILT_IN_GOMP_PARALLEL.
	(ipa_pta_execute): Same.  Handle node->parallelized_function as a local
	function.

	* gcc.dg/pr46032.c: New test.

	* testsuite/libgomp.c/pr46032.c: New test.

From-SVN: r231076

4 files changed, 121 insertions, 13 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 735fbd9..229aa77 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2015-11-30  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/46032
+	* tree-ssa-structalias.c (find_func_aliases_for_call_arg): New function,
+	factored out of ...
+	(find_func_aliases_for_call): ... here.
+	(find_func_aliases_for_builtin_call, find_func_clobbers): Handle
+	BUILT_IN_GOMP_PARALLEL.
+	(ipa_pta_execute): Same.  Handle node->parallelized_function as a local
+	function.
+
 2015-11-30  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/68501
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 368b4e7..c9283ad 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-11-30  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/46032
+	* gcc.dg/pr46032.c: New test.
+
 2015-11-30  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/68592
diff --git a/gcc/testsuite/gcc.dg/pr46032.c b/gcc/testsuite/gcc.dg/pr46032.c
new file mode 100644
index 0000000..b91190e
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr46032.c
@@ -0,0 +1,47 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fopenmp -ftree-vectorize -std=c99 -fipa-pta -fdump-tree-vect-all" } */
+
+extern void abort (void);
+
+#define nEvents 1000
+
+static void __attribute__((noinline, noclone, optimize("-fno-tree-vectorize")))
+init (unsigned *results, unsigned *pData)
+{
+  unsigned int i;
+  for (i = 0; i < nEvents; ++i)
+    pData[i] = i % 3;
+}
+
+static void __attribute__((noinline, noclone, optimize("-fno-tree-vectorize")))
+check (unsigned *results)
+{
+  unsigned sum = 0;
+  for (int idx = 0; idx < (int)nEvents; idx++)
+    sum += results[idx];
+
+  if (sum != 1998)
+    abort ();
+}
+
+int
+main (void)
+{
+  unsigned results[nEvents];
+  unsigned pData[nEvents];
+  unsigned coeff = 2;
+
+  init (&results[0], &pData[0]);
+
+#pragma omp parallel for
+  for (int idx = 0; idx < (int)nEvents; idx++)
+    results[idx] = coeff * pData[idx];
+
+  check (&results[0]);
+
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "note: vectorized 1 loop" 1 "vect" } } */
+/* { dg-final { scan-tree-dump-not "versioning for alias required" "vect" } } */
+
diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index f24ebeba..7f4a8ad 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -4139,6 +4139,24 @@ get_fi_for_callee (gcall *call)
   return get_vi_for_tree (fn);
 }
 
+/* Create constraints for assigning call argument ARG to the incoming parameter
+   INDEX of function FI.  */
+
+static void
+find_func_aliases_for_call_arg (varinfo_t fi, unsigned index, tree arg)
+{
+  struct constraint_expr lhs;
+  lhs = get_function_part_constraint (fi, fi_parm_base + index);
+
+  auto_vec<ce_s, 2> rhsc;
+  get_constraint_for_rhs (arg, &rhsc);
+
+  unsigned j;
+  struct constraint_expr *rhsp;
+  FOR_EACH_VEC_ELT (rhsc, j, rhsp)
+    process_constraint (new_constraint (lhs, *rhsp));
+}
+
 /* Create constraints for the builtin call T.  Return true if the call
    was handled, otherwise false.  */
 
@@ -4488,6 +4506,25 @@ find_func_aliases_for_builtin_call (struct function *fn, gcall *t)
 	    }
 	  return true;
 	}
+      case BUILT_IN_GOMP_PARALLEL:
+	{
+	  /* Handle __builtin_GOMP_parallel (fn, data, num_threads, flags) as
+	     fn (data).  */
+	  if (in_ipa_mode)
+	    {
+	      tree fnarg = gimple_call_arg (t, 0);
+	      gcc_assert (TREE_CODE (fnarg) == ADDR_EXPR);
+	      tree fndecl = TREE_OPERAND (fnarg, 0);
+	      tree arg = gimple_call_arg (t, 1);
+	      gcc_assert (TREE_CODE (arg) == ADDR_EXPR);
+
+	      varinfo_t fi = get_vi_for_tree (fndecl);
+	      find_func_aliases_for_call_arg (fi, 0, arg);
+	      return true;
+	    }
+	  /* Else fallthru to generic call handling.  */
+	  break;
+	}
       /* printf-style functions may have hooks to set pointers to
 	 point to somewhere into the generated string.  Leave them
 	 for a later exercise...  */
@@ -4546,18 +4583,8 @@ find_func_aliases_for_call (struct function *fn, gcall *t)
 	 parameters of the function.  */
       for (j = 0; j < gimple_call_num_args (t); j++)
 	{
-	  struct constraint_expr lhs ;
-	  struct constraint_expr *rhsp;
 	  tree arg = gimple_call_arg (t, j);
-
-	  get_constraint_for_rhs (arg, &rhsc);
-	  lhs = get_function_part_constraint (fi, fi_parm_base + j);
-	  while (rhsc.length () != 0)
-	    {
-	      rhsp = &rhsc.last ();
-	      process_constraint (new_constraint (lhs, *rhsp));
-	      rhsc.pop ();
-	    }
+	  find_func_aliases_for_call_arg (fi, j, arg);
 	}
 
       /* If we are returning a value, assign it to the result.  */
@@ -5036,6 +5063,8 @@ find_func_clobbers (struct function *fn, gimple *origt)
 	  case BUILT_IN_VA_START:
 	  case BUILT_IN_VA_END:
 	    return;
+	  case BUILT_IN_GOMP_PARALLEL:
+	    return;
 	  /* printf-style functions may have hooks to set pointers to
 	     point to somewhere into the generated string.  Leave them
 	     for a later exercise...  */
@@ -7345,6 +7374,18 @@ ipa_pta_execute (void)
 
       gcc_assert (!node->clone_of);
 
+      /* When parallelizing a code region, we split the region off into a
+	 separate function, to be run by several threads in parallel.  So for a
+	 function foo, we split off a region into a function
+	 foo._0 (void *foodata), and replace the region with some variant of a
+	 function call run_on_threads (&foo._0, data).  The '&foo._0' sets the
+	 address_taken bit for function foo._0, which would make it non-local.
+	 But for the purpose of ipa-pta, we can regard the run_on_threads call
+	 as a local call foo._0 (data),  so we ignore address_taken on nodes
+	 with parallelized_function set.  */
+      bool node_address_taken = (node->address_taken
+				 && !node->parallelized_function);
+
       /* For externally visible or attribute used annotated functions use
 	 local constraints for their arguments.
 	 For local functions we see all callers and thus do not need initial
@@ -7352,7 +7393,7 @@ ipa_pta_execute (void)
       bool nonlocal_p = (node->used_from_other_partition
 			 || node->externally_visible
 			 || node->force_output
-			 || node->address_taken);
+			 || node_address_taken);
 
       vi = create_function_info_for (node->decl,
 				     alias_get_name (node->decl), false,
@@ -7504,7 +7545,11 @@ ipa_pta_execute (void)
 		continue;
 
 	      /* Handle direct calls to functions with body.  */
-	      decl = gimple_call_fndecl (stmt);
+	      if (gimple_call_builtin_p (stmt, BUILT_IN_GOMP_PARALLEL))
+		decl = TREE_OPERAND (gimple_call_arg (stmt, 0), 0);
+	      else
+		decl = gimple_call_fndecl (stmt);
+
 	      if (decl
 		  && (fi = lookup_vi_for_tree (decl))
 		  && fi->is_fn_info)