re PR tree-optimization/85787 (malloc_candidate_p fails to detect malloc attribute...

2018-10-04  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>

	PR tree-optimization/85787
	* ipa-pure-const.c (malloc_candidate_p_1): Move most of malloc_candidate_p
	into this function and add support for detecting multiple phis.
	(DUMP_AND_RETURN): Move from malloc_candidate_p into top-level macro.

testsuite/
	* gcc.dg/ipa/propmalloc-4.c: New test.

From-SVN: r264838

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index fbf6862f5221322566c75b796df35187e72a634d..8022aabfc2166821655dfc9bcdb31c1920d1756c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2018-10-04  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>
+
+       PR tree-optimization/85787
+       * ipa-pure-const.c (malloc_candidate_p_1): Move most of malloc_candidate_p
+       into this function and add support for detecting multiple phis.
+       (DUMP_AND_RETURN): Move from malloc_candidate_p into top-level macro.
+
 2018-10-04  Martin Liska  <mliska@suse.cz>
 
        PR ipa/87491

diff --git a/gcc/ipa-pure-const.c b/gcc/ipa-pure-const.c
index a9a8863d907627908f37b5c5de3961fc14e3f10f..66c81be23ecd9844a5f38d7927f26b6971c7d330 100644 (file)
--- a/gcc/ipa-pure-const.c
+++ b/gcc/ipa-pure-const.c
@@ -869,14 +869,6 @@ check_retval_uses (tree retval, gimple *stmt)
       and return_stmt (and likewise a phi arg has immediate use only within comparison
       or the phi stmt).  */
 
-static bool
-malloc_candidate_p (function *fun, bool ipa)
-{
-  basic_block exit_block = EXIT_BLOCK_PTR_FOR_FN (fun);
-  edge e;
-  edge_iterator ei;
-  cgraph_node *node = cgraph_node::get_create (fun->decl);
-
 #define DUMP_AND_RETURN(reason)  \
 {  \
   if (dump_file && (dump_flags & TDF_DETAILS))  \
@@ -885,6 +877,96 @@ malloc_candidate_p (function *fun, bool ipa)
   return false;  \
 }
 
+static bool
+malloc_candidate_p_1 (function *fun, tree retval, gimple *ret_stmt, bool ipa)
+{
+  cgraph_node *node = cgraph_node::get_create (fun->decl);
+
+  if (!check_retval_uses (retval, ret_stmt))
+    DUMP_AND_RETURN("Return value has uses outside return stmt"
+                   " and comparisons against 0.")
+
+  gimple *def = SSA_NAME_DEF_STMT (retval);
+
+  if (gcall *call_stmt = dyn_cast<gcall *> (def))
+    {
+      tree callee_decl = gimple_call_fndecl (call_stmt);
+      if (!callee_decl)
+       return false;
+
+      if (!ipa && !DECL_IS_MALLOC (callee_decl))
+       DUMP_AND_RETURN("callee_decl does not have malloc attribute for"
+                       " non-ipa mode.")
+
+      cgraph_edge *cs = node->get_edge (call_stmt);
+      if (cs)
+       {
+         ipa_call_summary *es = ipa_call_summaries->get_create (cs);
+         es->is_return_callee_uncaptured = true;
+       }
+    }
+
+    else if (gphi *phi = dyn_cast<gphi *> (def))
+      {
+       bool all_args_zero = true;
+       for (unsigned i = 0; i < gimple_phi_num_args (phi); ++i)
+         {
+           tree arg = gimple_phi_arg_def (phi, i);
+           if (integer_zerop (arg))
+             continue;
+
+           all_args_zero = false;
+           if (TREE_CODE (arg) != SSA_NAME)
+             DUMP_AND_RETURN ("phi arg is not SSA_NAME.");
+           if (!check_retval_uses (arg, phi))
+             DUMP_AND_RETURN ("phi arg has uses outside phi"
+                                " and comparisons against 0.")
+
+           gimple *arg_def = SSA_NAME_DEF_STMT (arg);
+           if (is_a<gphi *> (arg_def))
+             {
+               if (!malloc_candidate_p_1 (fun, arg, phi, ipa))
+                   DUMP_AND_RETURN ("nested phi fail")
+               continue;
+             }
+
+           gcall *call_stmt = dyn_cast<gcall *> (arg_def);
+           if (!call_stmt)
+             DUMP_AND_RETURN ("phi arg is a not a call_stmt.")
+
+           tree callee_decl = gimple_call_fndecl (call_stmt);
+           if (!callee_decl)
+             return false;
+           if (!ipa && !DECL_IS_MALLOC (callee_decl))
+             DUMP_AND_RETURN("callee_decl does not have malloc attribute"
+                             " for non-ipa mode.")
+
+           cgraph_edge *cs = node->get_edge (call_stmt);
+           if (cs)
+             {
+               ipa_call_summary *es = ipa_call_summaries->get_create (cs);
+               es->is_return_callee_uncaptured = true;
+             }
+         }
+
+       if (all_args_zero)
+         DUMP_AND_RETURN ("Return value is a phi with all args equal to 0.")
+      }
+
+    else
+      DUMP_AND_RETURN("def_stmt of return value is not a call or phi-stmt.")
+
+  return true;
+}
+
+static bool
+malloc_candidate_p (function *fun, bool ipa)
+{
+  basic_block exit_block = EXIT_BLOCK_PTR_FOR_FN (fun);
+  edge e;
+  edge_iterator ei;
+  cgraph_node *node = cgraph_node::get_create (fun->decl);
+
   if (EDGE_COUNT (exit_block->preds) == 0
       || !flag_delete_null_pointer_checks)
     return false;
@@ -905,80 +987,17 @@ malloc_candidate_p (function *fun, bool ipa)
          || TREE_CODE (TREE_TYPE (retval)) != POINTER_TYPE)
        DUMP_AND_RETURN("Return value is not SSA_NAME or not a pointer type.")
 
-      if (!check_retval_uses (retval, ret_stmt))
-       DUMP_AND_RETURN("Return value has uses outside return stmt"
-                       " and comparisons against 0.")
-
-      gimple *def = SSA_NAME_DEF_STMT (retval);
-      if (gcall *call_stmt = dyn_cast<gcall *> (def))
-       {
-         tree callee_decl = gimple_call_fndecl (call_stmt);
-         if (!callee_decl)
-           return false;
-
-         if (!ipa && !DECL_IS_MALLOC (callee_decl))
-           DUMP_AND_RETURN("callee_decl does not have malloc attribute for"
-                           " non-ipa mode.")
-
-         cgraph_edge *cs = node->get_edge (call_stmt);
-         if (cs)
-           {
-             ipa_call_summary *es = ipa_call_summaries->get_create (cs);
-             es->is_return_callee_uncaptured = true;
-           }
-       }
-
-      else if (gphi *phi = dyn_cast<gphi *> (def))
-       {
-         bool all_args_zero = true;
-         for (unsigned i = 0; i < gimple_phi_num_args (phi); ++i)
-           {
-             tree arg = gimple_phi_arg_def (phi, i);
-             if (integer_zerop (arg))
-               continue;
-
-             all_args_zero = false;
-             if (TREE_CODE (arg) != SSA_NAME)
-               DUMP_AND_RETURN ("phi arg is not SSA_NAME.");
-             if (!check_retval_uses (arg, phi))
-               DUMP_AND_RETURN ("phi arg has uses outside phi"
-                                " and comparisons against 0.")
-
-             gimple *arg_def = SSA_NAME_DEF_STMT (arg);
-             gcall *call_stmt = dyn_cast<gcall *> (arg_def);
-             if (!call_stmt)
-               return false;
-             tree callee_decl = gimple_call_fndecl (call_stmt);
-             if (!callee_decl)
-               return false;
-             if (!ipa && !DECL_IS_MALLOC (callee_decl))
-               DUMP_AND_RETURN("callee_decl does not have malloc attribute"
-                               " for non-ipa mode.")
-
-             cgraph_edge *cs = node->get_edge (call_stmt);
-             if (cs)
-               {
-                 ipa_call_summary *es = ipa_call_summaries->get_create (cs);
-                 es->is_return_callee_uncaptured = true;
-               }
-           }
-
-         if (all_args_zero)
-           DUMP_AND_RETURN ("Return value is a phi with all args equal to 0.");
-       }
-
-      else
-       DUMP_AND_RETURN("def_stmt of return value is not a call or phi-stmt.")
+      if (!malloc_candidate_p_1 (fun, retval, ret_stmt, ipa))
+       return false;
     }
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     fprintf (dump_file, "\nFound %s to be candidate for malloc attribute\n",
             IDENTIFIER_POINTER (DECL_NAME (fun->decl)));
   return true;
-
-#undef DUMP_AND_RETURN
 }
 
+#undef DUMP_AND_RETURN
 
 /* This is the main routine for finding the reference patterns for
    global variables within a function FN.  */

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 55af1bd5b3e4da673f9002bf07e9f9a4098c05ce..a6865fee246a18be80c093cf302f509e5593daff 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-10-04  Prathamesh Kulkarni  <prathamesh.kulkarni@linaro.org>
+
+       PR tree-optimization/85787
+       * gcc.dg/ipa/propmalloc-4.c: New test.
+
 2018-10-04  Richard Biener  <rguenther@suse.de>
 
        * gcc.dg/tree-ssa/cunroll-15.c: Add XFAILs for arm and powerpc.

diff --git a/gcc/testsuite/gcc.dg/ipa/propmalloc-4.c b/gcc/testsuite/gcc.dg/ipa/propmalloc-4.c
new file mode 100644 (file)
index 0000000..4c40d63
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/propmalloc-4.c
@@ -0,0 +1,56 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-local-pure-const-details" } */
+
+void *foo(int cond1, int cond2, int cond3)
+{
+  void *ret;
+  void *a;
+  void *b;
+
+  if (cond1)
+    a = __builtin_malloc (10);
+  else
+    a = __builtin_malloc (20);
+
+  if (cond2)
+    b = __builtin_malloc (30);
+  else
+    b = __builtin_malloc (40);
+
+  if (cond3)
+    ret = a;
+  else
+    ret = b;
+
+  return ret;
+}
+
+void *foo2(int cond1, int cond2, int cond3)
+{
+  void *ret;
+  void *a;
+  void *b;
+  void bar(void *, void *);
+
+  if (cond1)
+    a = __builtin_malloc (10);
+  else
+    a = __builtin_malloc (20);
+
+  if (cond2)
+    b = __builtin_malloc (30);
+  else
+    b = __builtin_malloc (40);
+
+  bar (a, b);
+
+  if (cond3)
+    ret = a;
+  else
+    ret = b;
+
+  return ret;
+}
+
+/* { dg-final { scan-tree-dump "Function found to be malloc: foo" "local-pure-const1" } } */
+/* { dg-final { scan-tree-dump-not "Function found to be malloc: foo2" "local-pure-const1" } } */