re PR tree-optimization/90037 (-Wnull-dereference false positive after r269302)

	PR tree-optimization/90037
	* Makefile.in (OBJS): Remove tree-ssa-phionlycprop.c
	* passes.def: Replace all instance of phi-only cprop with the
	lattice propagator.  Move propagation pass from after erroneous
	path isolation to before erroneous path isolation.
	* tree-ssa-phionlycprop.c: Remove.

	* gcc.dg/tree-ssa/20030710-1.c: Update dump file to scan.
	* gcc.dg/isolate-2.c: Likewise.
	* gcc.dg/isolate-4.c: Likewise.
	* gcc.dg/pr19431.c: Accept either ordering of PHI args.
	* gcc.dg/pr90037.c: New test.

From-SVN: r270574

gcc/ChangeLog

+2019-04-24  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/90037
+	* Makefile.in (OBJS): Remove tree-ssa-phionlycprop.c
+	* passes.def: Replace all instance of phi-only cprop with the
+	lattice propagator.  Move propagation pass from after erroneous
+	path isolation to before erroneous path isolation.
+	* tree-ssa-phionlycprop.c: Remove.
+
 2019-04-24  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/90213

gcc/Makefile.in

@@ -1559,7 +1559,6 @@ OBJS = \
 	tree-ssa-loop.o \
 	tree-ssa-math-opts.o \
 	tree-ssa-operands.o \
-	tree-ssa-phionlycprop.o \
 	tree-ssa-phiopt.o \
 	tree-ssa-phiprop.o \
 	tree-ssa-pre.o \

gcc/passes.def

@@ -222,19 +222,13 @@ along with GCC; see the file COPYING3.  If not see
 	 trying to move or duplicate pass_dominator somewhere earlier.  */
       NEXT_PASS (pass_thread_jumps);
       NEXT_PASS (pass_dominator, true /* may_peel_loop_headers_p */);
-      /* At this point the majority of const/copy propagations
-	 are exposed.  Go ahead and identify paths that should never
-	 be executed in a conforming program and isolate those paths.
-
-	 This will expose more degenerate PHIs in the main path and
-	 expose more PRE/DOM optimization opportunities.  */
+      /* Threading can leave many const/copy propagations in the IL.
+	 Clean them up.  Failure to do so well can lead to false
+	 positives from warnings for erroneous code.  */
+      NEXT_PASS (pass_copy_prop);
+      /* Identify paths that should never be executed in a conforming
+	 program and isolate those paths.  */
       NEXT_PASS (pass_isolate_erroneous_paths);
-      /* The only const/copy propagation opportunities left after
-	 DOM and erroneous path isolation should be due to degenerate PHI nodes.
-	 So rather than run the full propagators, run a specialized pass which
-	 only examines PHIs to discover const/copy propagation
-	 opportunities.  */
-      NEXT_PASS (pass_phi_only_cprop);
       NEXT_PASS (pass_dse);
       NEXT_PASS (pass_reassoc, true /* insert_powi_p */);
       NEXT_PASS (pass_dce);
@@ -321,13 +315,10 @@ along with GCC; see the file COPYING3.  If not see
       NEXT_PASS (pass_strlen);
       NEXT_PASS (pass_thread_jumps);
       NEXT_PASS (pass_vrp, false /* warn_array_bounds_p */);
-      /* The only const/copy propagation opportunities left after
-	 DOM and VRP should be due to degenerate PHI nodes.  So rather than
-	 run the full propagators, run a specialized pass which
-	 only examines PHIs to discover const/copy propagation
-	 opportunities.  */
       NEXT_PASS (pass_warn_restrict);
-      NEXT_PASS (pass_phi_only_cprop);
+      /* Threading can leave many const/copy propagations in the IL.
+	 Clean them up.  */
+      NEXT_PASS (pass_copy_prop);
       NEXT_PASS (pass_dse);
       NEXT_PASS (pass_cd_dce);
       NEXT_PASS (pass_forwprop);

gcc/testsuite/ChangeLog

+2019-04-24  Jeff Law  <law@redhat.com>
+
+	PR tree-optimization/90037
+	* gcc.dg/tree-ssa/20030710-1.c: Update dump file to scan.
+	* gcc.dg/isolate-2.c: Likewise.
+	* gcc.dg/isolate-4.c: Likewise.
+	* gcc.dg/pr19431.c: Accept either ordering of PHI args.
+	* gcc.dg/pr90037.c: New test.
+
 2019-04-25  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/44648

gcc/testsuite/gcc.dg/pr90037.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -Wnull-dereference" } */
+
+typedef __SIZE_TYPE__ size_t;
+typedef unsigned long int uintmax_t;
+
+struct group
+{
+  char *gr_name;
+  char *gr_passwd;
+  unsigned gr_gid;
+  char **gr_mem;
+};
+
+struct passwd
+{
+  char *pw_name;
+  char *pw_passwd;
+
+  unsigned pw_uid;
+  unsigned pw_gid;
+  char *pw_gecos;
+  char *pw_dir;
+  char *pw_shell;
+};
+
+extern struct group *getgrnam (const char *);
+extern struct group *getgrgid (unsigned);
+extern void endgrent (void);
+extern struct passwd *getpwnam (const char *);
+extern void endpwent (void);
+extern unsigned long int strtoul (const char *__restrict,
+				  char **__restrict, int);
+
+char const *
+parse_with_separator (char const *spec, char const *separator,
+                      unsigned *uid, unsigned *gid,
+                      char **username, char **groupname)
+{
+  static const char *E_invalid_user = "invalid user";
+  static const char *E_invalid_group = "invalid group";
+  static const char *E_bad_spec = "invalid spec";
+  const char *error_msg;
+  struct passwd *pwd;
+  struct group *grp;
+  char *u;
+  char const *g;
+  char *gname = 0;
+  unsigned unum = *uid;
+  unsigned gnum = gid ? *gid : (unsigned)-1;
+
+  error_msg = 0;
+
+  if (username)
+    *username = 0;
+
+  if (groupname)
+    *groupname = 0;
+
+  u = 0;
+  if (separator == 0)
+    {
+      if (*spec)
+        u = __builtin_strdup (spec);
+    }
+  else
+    {
+      size_t ulen = separator - spec;
+      if (ulen != 0)
+        {
+          u = __builtin_malloc (ulen + 1);
+          __builtin_memcpy (u, spec, ulen + 1);
+          u[ulen] = '\0';
+        }
+    }
+
+  g = (separator == 0 || *(separator + 1) == '\0' ? 0 : separator + 1);
+
+  if (u != 0)
+    {
+      pwd = (*u == '+' ? 0 : getpwnam (u));
+      if (pwd == 0)
+        {
+	  _Bool use_login_group = (separator != 0 && g == 0);
+          if (use_login_group)
+            {
+              error_msg = E_bad_spec;
+            }
+          else
+            {
+              unsigned long int tmp;
+              tmp = strtoul (u, 0, 10);
+              if (tmp <= (1ul << 31) && (unsigned) tmp != (unsigned) -1)
+                unum = tmp;
+              else
+                error_msg = E_invalid_user;
+            }
+        }
+      else
+        {
+          unum = pwd->pw_uid;
+          if (g == 0 && separator != 0)
+            {
+              char buf[128];
+              gnum = pwd->pw_gid;
+              grp = getgrgid (gnum);
+
+              gname = buf;
+
+              if (grp)
+		gname = __builtin_strdup (grp->gr_name);
+              else
+		__builtin_snprintf (buf, sizeof(buf), "%ju", (uintmax_t)gnum);
+
+              endgrent ();
+            }
+        }
+
+      endpwent ();
+    }
+
+  if (g != 0 && error_msg == 0)
+    {
+      grp = (*g == '+' ? 0 : getgrnam (g));
+      if (grp == 0)
+        {
+	  unsigned long int tmp = strtoul (g, 0, 10);
+		
+	  if (tmp <= (1ul << 31) && (unsigned) tmp != (unsigned) -1)
+            gnum = tmp;
+          else
+            error_msg = E_invalid_group;
+        }
+      else
+        gnum = grp->gr_gid;
+      endgrent ();
+      gname = __builtin_strdup (g);
+    }
+
+  if (error_msg == 0)
+    {
+      *uid = unum;
+      if (gid)
+        *gid = gnum;
+      if (username)
+        {
+          *username = u;
+          u = 0;
+        }
+      if (groupname)
+        {
+          *groupname = gname;
+          gname = 0;
+        }
+    }
+
+  __builtin_free (u);
+  __builtin_free (gname);
+  return error_msg ? error_msg : 0;
+}
+

gcc/testsuite/gcc.dg/tree-ssa/20030710-1.c

 /* { dg-do compile } */
-/* { dg-options "-O1 -fdump-tree-phicprop1" } */
+/* { dg-options "-O1 -fdump-tree-copyprop2" } */
 
 extern void abort (void);
 extern void blah (void);
@@ -42,14 +42,14 @@ record_component_aliases (type)
 /* The call to blah should have been eliminated.  If the call is not
    eliminated, then dominator optimizations failed and it'll be
    impossible to delete other unnecessary code.  */
-/* { dg-final { scan-tree-dump-not "blah \\(\\)" "phicprop1" } } */
+/* { dg-final { scan-tree-dump-not "blah \\(\\)" "copyprop2" } } */
   
 /* There should be two IF conditionals.  */
-/* { dg-final { scan-tree-dump-times "if " 2 "phicprop1"} } */
+/* { dg-final { scan-tree-dump-times "if " 2 "copyprop2"} } */
                                                                                 
 /* There should be a single load of type.binfo.  */
-/* { dg-final { scan-tree-dump-times "type\\.binfo" 1 "phicprop1"} } */
+/* { dg-final { scan-tree-dump-times "type\\.binfo" 1 "copyprop2"} } */
 
 /* There should be two loads of vec.length.  */
-/* { dg-final { scan-tree-dump-times "vec.length" 2 "phicprop1"} } */
+/* { dg-final { scan-tree-dump-times "vec.length" 2 "copyprop2"} } */
 

gcc/testsuite/gcc.dg/tree-ssa/isolate-2.c

 /* { dg-do compile } */ 
-/* { dg-options "-O2 -fdelete-null-pointer-checks -fisolate-erroneous-paths-attribute -fdump-tree-isolate-paths -fdump-tree-phicprop1" } */
+/* { dg-options "-O2 -fdelete-null-pointer-checks -fisolate-erroneous-paths-attribute -fdump-tree-isolate-paths -fdump-tree-forwprop3" } */
 /* { dg-skip-if "" keeps_null_pointer_checks } */
 
 
@@ -34,9 +34,9 @@ bar (void)
    a return statement.  We test this twice, once where the NULL flows
    from a PHI, the second with an explicit return 0 in the IL.
 
-   We also verify that after isolation phi-cprop simplifies the
+   We also verify that after isolation cprop simplifies the
    return statement so that it returns &z directly. */
 /* { dg-final { scan-tree-dump-times "__builtin_trap" 2 "isolate-paths"} } */
-/* { dg-final { scan-tree-dump-times "return &z;" 1 "phicprop1"} } */
+/* { dg-final { scan-tree-dump-times "return &z;" 1 "forwprop3"} } */
 
 

gcc/testsuite/gcc.dg/tree-ssa/isolate-4.c

 /* { dg-do compile } */ 
-/* { dg-options "-O2 -fdelete-null-pointer-checks -fisolate-erroneous-paths-attribute -fdump-tree-isolate-paths -fdump-tree-phicprop1" } */
+/* { dg-options "-O2 -fdelete-null-pointer-checks -fisolate-erroneous-paths-attribute -fdump-tree-isolate-paths -fdump-tree-ccp3" } */
 /* { dg-skip-if "" keeps_null_pointer_checks } */
 
 
@@ -26,6 +26,6 @@ bar (void)
    We also verify that after isolation phi-cprop simplifies the
    return statement so that it returns &z directly. */
 /* { dg-final { scan-tree-dump-times "__builtin_trap" 2 "isolate-paths"} } */
-/* { dg-final { scan-tree-dump-times "foo .&z.;" 1 "phicprop1"} } */
+/* { dg-final { scan-tree-dump-times "foo .&z.;" 1 "ccp3"} } */
 
 

gcc/testsuite/gcc.dg/tree-ssa/pr19431.c

@@ -24,4 +24,4 @@ int f(int k, int i1, int j1)
   return *f1;
 }
 
-/* { dg-final { scan-tree-dump "\[^\r\n\]*_. = PHI <i1_\[^,\]*, j1_\[^>\]*>" "optimized" } } */
+/* { dg-final { scan-tree-dump "\[^\r\n\]*_. = PHI <\[ij\]1_\[^,\]*, \[ij\]1_\[^>\]*>" "optimized" } } */