tree-ssa-structalias.c (find_func_aliases_for_builtin_call): New function split out...
authorRichard Guenther <rguenther@suse.de>
Thu, 28 Apr 2011 09:08:42 +0000 (09:08 +0000)
committerRichard Biener <rguenth@gcc.gnu.org>
Thu, 28 Apr 2011 09:08:42 +0000 (09:08 +0000)
2011-04-28  Richard Guenther  <rguenther@suse.de>

* tree-ssa-structalias.c (find_func_aliases_for_builtin_call):
New function split out from ...
(find_func_aliases): ... here.  Call it.
(find_func_aliases_for_call): Likewise.

From-SVN: r173060

gcc/ChangeLog
gcc/tree-ssa-structalias.c

index cbaa0e62600fed7e077852d518443d1272059756..7c74bba013df4e3014b9492e4596ba5585742491 100644 (file)
@@ -1,3 +1,10 @@
+2011-04-28  Richard Guenther  <rguenther@suse.de>
+
+       * tree-ssa-structalias.c (find_func_aliases_for_builtin_call):
+       New function split out from ...
+       (find_func_aliases): ... here.  Call it.
+       (find_func_aliases_for_call): Likewise.
+
 2011-04-27  Gabriel Dos Reis  <gdr@integrable-solutions.net>
 
        * internal-fn.h (internal_fn_name_array): Declare.
index 9bae3ff319c399ae3c9c691f89f0df117853cdb5..6dc0a2c8596e106a53c373467ec34e0a9246fe2f 100644 (file)
@@ -3959,375 +3959,406 @@ get_fi_for_callee (gimple call)
     gcc_unreachable ();
 }
 
-/* Walk statement T setting up aliasing constraints according to the
-   references found in T.  This function is the main part of the
-   constraint builder.  AI points to auxiliary alias information used
-   when building alias sets and computing alias grouping heuristics.  */
+/* Create constraints for the builtin call T.  Return true if the call
+   was handled, otherwise false.  */
 
-static void
-find_func_aliases (gimple origt)
+static bool
+find_func_aliases_for_builtin_call (gimple t)
 {
-  gimple t = origt;
+  tree fndecl = gimple_call_fndecl (t);
   VEC(ce_s, heap) *lhsc = NULL;
   VEC(ce_s, heap) *rhsc = NULL;
-  struct constraint_expr *c;
   varinfo_t fi;
 
-  /* Now build constraints expressions.  */
-  if (gimple_code (t) == GIMPLE_PHI)
-    {
-      size_t i;
-      unsigned int j;
-
-      /* For a phi node, assign all the arguments to
-        the result.  */
-      get_constraint_for (gimple_phi_result (t), &lhsc);
-      for (i = 0; i < gimple_phi_num_args (t); i++)
+  if (fndecl != NULL_TREE
+      && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
+    /* ???  All builtins that are handled here need to be handled
+       in the alias-oracle query functions explicitly!  */
+    switch (DECL_FUNCTION_CODE (fndecl))
+      {
+      /* All the following functions return a pointer to the same object
+        as their first argument points to.  The functions do not add
+        to the ESCAPED solution.  The functions make the first argument
+        pointed to memory point to what the second argument pointed to
+        memory points to.  */
+      case BUILT_IN_STRCPY:
+      case BUILT_IN_STRNCPY:
+      case BUILT_IN_BCOPY:
+      case BUILT_IN_MEMCPY:
+      case BUILT_IN_MEMMOVE:
+      case BUILT_IN_MEMPCPY:
+      case BUILT_IN_STPCPY:
+      case BUILT_IN_STPNCPY:
+      case BUILT_IN_STRCAT:
+      case BUILT_IN_STRNCAT:
        {
-         tree strippedrhs = PHI_ARG_DEF (t, i);
-
-         STRIP_NOPS (strippedrhs);
-         get_constraint_for_rhs (gimple_phi_arg_def (t, i), &rhsc);
-
-         FOR_EACH_VEC_ELT (ce_s, lhsc, j, c)
+         tree res = gimple_call_lhs (t);
+         tree dest = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl)
+                                          == BUILT_IN_BCOPY ? 1 : 0));
+         tree src = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl)
+                                         == BUILT_IN_BCOPY ? 0 : 1));
+         if (res != NULL_TREE)
            {
-             struct constraint_expr *c2;
-             while (VEC_length (ce_s, rhsc) > 0)
-               {
-                 c2 = VEC_last (ce_s, rhsc);
-                 process_constraint (new_constraint (*c, *c2));
-                 VEC_pop (ce_s, rhsc);
-               }
+             get_constraint_for (res, &lhsc);
+             if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMPCPY
+                 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPCPY
+                 || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPNCPY)
+               get_constraint_for_ptr_offset (dest, NULL_TREE, &rhsc);
+             else
+               get_constraint_for (dest, &rhsc);
+             process_all_all_constraints (lhsc, rhsc);
+             VEC_free (ce_s, heap, lhsc);
+             VEC_free (ce_s, heap, rhsc);
            }
+         get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
+         get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
+         do_deref (&lhsc);
+         do_deref (&rhsc);
+         process_all_all_constraints (lhsc, rhsc);
+         VEC_free (ce_s, heap, lhsc);
+         VEC_free (ce_s, heap, rhsc);
+         return true;
        }
-    }
-  /* In IPA mode, we need to generate constraints to pass call
-     arguments through their calls.   There are two cases,
-     either a GIMPLE_CALL returning a value, or just a plain
-     GIMPLE_CALL when we are not.
-
-     In non-ipa mode, we need to generate constraints for each
-     pointer passed by address.  */
-  else if (is_gimple_call (t))
-    {
-      tree fndecl = gimple_call_fndecl (t);
-      if (fndecl != NULL_TREE
-         && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
-       /* ???  All builtins that are handled here need to be handled
-          in the alias-oracle query functions explicitly!  */
-       switch (DECL_FUNCTION_CODE (fndecl))
-         {
-         /* All the following functions return a pointer to the same object
-            as their first argument points to.  The functions do not add
-            to the ESCAPED solution.  The functions make the first argument
-            pointed to memory point to what the second argument pointed to
-            memory points to.  */
-         case BUILT_IN_STRCPY:
-         case BUILT_IN_STRNCPY:
-         case BUILT_IN_BCOPY:
-         case BUILT_IN_MEMCPY:
-         case BUILT_IN_MEMMOVE:
-         case BUILT_IN_MEMPCPY:
-         case BUILT_IN_STPCPY:
-         case BUILT_IN_STPNCPY:
-         case BUILT_IN_STRCAT:
-         case BUILT_IN_STRNCAT:
+      case BUILT_IN_MEMSET:
+       {
+         tree res = gimple_call_lhs (t);
+         tree dest = gimple_call_arg (t, 0);
+         unsigned i;
+         ce_s *lhsp;
+         struct constraint_expr ac;
+         if (res != NULL_TREE)
            {
-             tree res = gimple_call_lhs (t);
-             tree dest = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl)
-                                              == BUILT_IN_BCOPY ? 1 : 0));
-             tree src = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl)
-                                             == BUILT_IN_BCOPY ? 0 : 1));
-             if (res != NULL_TREE)
-               {
-                 get_constraint_for (res, &lhsc);
-                 if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMPCPY
-                     || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPCPY
-                     || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPNCPY)
-                   get_constraint_for_ptr_offset (dest, NULL_TREE, &rhsc);
-                 else
-                   get_constraint_for (dest, &rhsc);
-                 process_all_all_constraints (lhsc, rhsc);
-                 VEC_free (ce_s, heap, lhsc);
-                 VEC_free (ce_s, heap, rhsc);
-               }
-             get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
-             get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc);
-             do_deref (&lhsc);
-             do_deref (&rhsc);
+             get_constraint_for (res, &lhsc);
+             get_constraint_for (dest, &rhsc);
              process_all_all_constraints (lhsc, rhsc);
              VEC_free (ce_s, heap, lhsc);
              VEC_free (ce_s, heap, rhsc);
-             return;
            }
-         case BUILT_IN_MEMSET:
+         get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
+         do_deref (&lhsc);
+         if (flag_delete_null_pointer_checks
+             && integer_zerop (gimple_call_arg (t, 1)))
            {
-             tree res = gimple_call_lhs (t);
-             tree dest = gimple_call_arg (t, 0);
-             unsigned i;
-             ce_s *lhsp;
-             struct constraint_expr ac;
-             if (res != NULL_TREE)
-               {
-                 get_constraint_for (res, &lhsc);
-                 get_constraint_for (dest, &rhsc);
-                 process_all_all_constraints (lhsc, rhsc);
-                 VEC_free (ce_s, heap, lhsc);
-                 VEC_free (ce_s, heap, rhsc);
-               }
-             get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc);
-             do_deref (&lhsc);
-             if (flag_delete_null_pointer_checks
-                 && integer_zerop (gimple_call_arg (t, 1)))
-               {
-                 ac.type = ADDRESSOF;
-                 ac.var = nothing_id;
-               }
-             else
-               {
-                 ac.type = SCALAR;
-                 ac.var = integer_id;
-               }
-             ac.offset = 0;
-             FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
-               process_constraint (new_constraint (*lhsp, ac));
-             VEC_free (ce_s, heap, lhsc);
-             return;
+             ac.type = ADDRESSOF;
+             ac.var = nothing_id;
            }
-         /* All the following functions do not return pointers, do not
-            modify the points-to sets of memory reachable from their
-            arguments and do not add to the ESCAPED solution.  */
-         case BUILT_IN_SINCOS:
-         case BUILT_IN_SINCOSF:
-         case BUILT_IN_SINCOSL:
-         case BUILT_IN_FREXP:
-         case BUILT_IN_FREXPF:
-         case BUILT_IN_FREXPL:
-         case BUILT_IN_GAMMA_R:
-         case BUILT_IN_GAMMAF_R:
-         case BUILT_IN_GAMMAL_R:
-         case BUILT_IN_LGAMMA_R:
-         case BUILT_IN_LGAMMAF_R:
-         case BUILT_IN_LGAMMAL_R:
-         case BUILT_IN_MODF:
-         case BUILT_IN_MODFF:
-         case BUILT_IN_MODFL:
-         case BUILT_IN_REMQUO:
-         case BUILT_IN_REMQUOF:
-         case BUILT_IN_REMQUOL:
-         case BUILT_IN_FREE:
-           return;
-         /* Trampolines are special - they set up passing the static
-            frame.  */
-         case BUILT_IN_INIT_TRAMPOLINE:
+         else
            {
-             tree tramp = gimple_call_arg (t, 0);
-             tree nfunc = gimple_call_arg (t, 1);
-             tree frame = gimple_call_arg (t, 2);
-             unsigned i;
-             struct constraint_expr lhs, *rhsp;
-             if (in_ipa_mode)
-               {
-                 varinfo_t nfi = NULL;
-                 gcc_assert (TREE_CODE (nfunc) == ADDR_EXPR);
-                 nfi = lookup_vi_for_tree (TREE_OPERAND (nfunc, 0));
-                 if (nfi)
-                   {
-                     lhs = get_function_part_constraint (nfi, fi_static_chain);
-                     get_constraint_for (frame, &rhsc);
-                     FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
-                       process_constraint (new_constraint (lhs, *rhsp));
-                     VEC_free (ce_s, heap, rhsc);
-
-                     /* Make the frame point to the function for
-                        the trampoline adjustment call.  */
-                     get_constraint_for (tramp, &lhsc);
-                     do_deref (&lhsc);
-                     get_constraint_for (nfunc, &rhsc);
-                     process_all_all_constraints (lhsc, rhsc);
-                     VEC_free (ce_s, heap, rhsc);
-                     VEC_free (ce_s, heap, lhsc);
-
-                     return;
-                   }
-               }
-             /* Else fallthru to generic handling which will let
-                the frame escape.  */
-             break;
+             ac.type = SCALAR;
+             ac.var = integer_id;
            }
-         case BUILT_IN_ADJUST_TRAMPOLINE:
+         ac.offset = 0;
+         FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+             process_constraint (new_constraint (*lhsp, ac));
+         VEC_free (ce_s, heap, lhsc);
+         return true;
+       }
+      /* All the following functions do not return pointers, do not
+        modify the points-to sets of memory reachable from their
+        arguments and do not add to the ESCAPED solution.  */
+      case BUILT_IN_SINCOS:
+      case BUILT_IN_SINCOSF:
+      case BUILT_IN_SINCOSL:
+      case BUILT_IN_FREXP:
+      case BUILT_IN_FREXPF:
+      case BUILT_IN_FREXPL:
+      case BUILT_IN_GAMMA_R:
+      case BUILT_IN_GAMMAF_R:
+      case BUILT_IN_GAMMAL_R:
+      case BUILT_IN_LGAMMA_R:
+      case BUILT_IN_LGAMMAF_R:
+      case BUILT_IN_LGAMMAL_R:
+      case BUILT_IN_MODF:
+      case BUILT_IN_MODFF:
+      case BUILT_IN_MODFL:
+      case BUILT_IN_REMQUO:
+      case BUILT_IN_REMQUOF:
+      case BUILT_IN_REMQUOL:
+      case BUILT_IN_FREE:
+       return true;
+      /* Trampolines are special - they set up passing the static
+        frame.  */
+      case BUILT_IN_INIT_TRAMPOLINE:
+       {
+         tree tramp = gimple_call_arg (t, 0);
+         tree nfunc = gimple_call_arg (t, 1);
+         tree frame = gimple_call_arg (t, 2);
+         unsigned i;
+         struct constraint_expr lhs, *rhsp;
+         if (in_ipa_mode)
            {
-             tree tramp = gimple_call_arg (t, 0);
-             tree res = gimple_call_lhs (t);
-             if (in_ipa_mode && res)
+             varinfo_t nfi = NULL;
+             gcc_assert (TREE_CODE (nfunc) == ADDR_EXPR);
+             nfi = lookup_vi_for_tree (TREE_OPERAND (nfunc, 0));
+             if (nfi)
                {
-                 get_constraint_for (res, &lhsc);
-                 get_constraint_for (tramp, &rhsc);
-                 do_deref (&rhsc);
+                 lhs = get_function_part_constraint (nfi, fi_static_chain);
+                 get_constraint_for (frame, &rhsc);
+                 FOR_EACH_VEC_ELT (ce_s, rhsc, i, rhsp)
+                     process_constraint (new_constraint (lhs, *rhsp));
+                 VEC_free (ce_s, heap, rhsc);
+
+                 /* Make the frame point to the function for
+                    the trampoline adjustment call.  */
+                 get_constraint_for (tramp, &lhsc);
+                 do_deref (&lhsc);
+                 get_constraint_for (nfunc, &rhsc);
                  process_all_all_constraints (lhsc, rhsc);
                  VEC_free (ce_s, heap, rhsc);
                  VEC_free (ce_s, heap, lhsc);
+
+                 return true;
                }
-             return;
            }
-         /* Variadic argument handling needs to be handled in IPA
-            mode as well.  */
-         case BUILT_IN_VA_START:
+         /* Else fallthru to generic handling which will let
+            the frame escape.  */
+         break;
+       }
+      case BUILT_IN_ADJUST_TRAMPOLINE:
+       {
+         tree tramp = gimple_call_arg (t, 0);
+         tree res = gimple_call_lhs (t);
+         if (in_ipa_mode && res)
            {
-             if (in_ipa_mode)
-               {
-                 tree valist = gimple_call_arg (t, 0);
-                 struct constraint_expr rhs, *lhsp;
-                 unsigned i;
-                 /* The va_list gets access to pointers in variadic
-                    arguments.  */
-                 fi = lookup_vi_for_tree (cfun->decl);
-                 gcc_assert (fi != NULL);
-                 get_constraint_for (valist, &lhsc);
-                 do_deref (&lhsc);
-                 rhs = get_function_part_constraint (fi, ~0);
-                 rhs.type = ADDRESSOF;
-                 FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
-                   process_constraint (new_constraint (*lhsp, rhs));
-                 VEC_free (ce_s, heap, lhsc);
-                 /* va_list is clobbered.  */
-                 make_constraint_to (get_call_clobber_vi (t)->id, valist);
-                 return;
-               }
-             break;
+             get_constraint_for (res, &lhsc);
+             get_constraint_for (tramp, &rhsc);
+             do_deref (&rhsc);
+             process_all_all_constraints (lhsc, rhsc);
+             VEC_free (ce_s, heap, rhsc);
+             VEC_free (ce_s, heap, lhsc);
            }
-         /* va_end doesn't have any effect that matters.  */
-         case BUILT_IN_VA_END:
-           return;
-         /* Alternate return.  Simply give up for now.  */
-         case BUILT_IN_RETURN:
+         return true;
+       }
+      /* Variadic argument handling needs to be handled in IPA
+        mode as well.  */
+      case BUILT_IN_VA_START:
+       {
+         if (in_ipa_mode)
            {
-             fi = NULL;
-             if (!in_ipa_mode
-                 || !(fi = get_vi_for_tree (cfun->decl)))
-               make_constraint_from (get_varinfo (escaped_id), anything_id);
-             else if (in_ipa_mode
-                      && fi != NULL)
-               {
-                 struct constraint_expr lhs, rhs;
-                 lhs = get_function_part_constraint (fi, fi_result);
-                 rhs.var = anything_id;
-                 rhs.offset = 0;
-                 rhs.type = SCALAR;
-                 process_constraint (new_constraint (lhs, rhs));
-               }
-             return;
+             tree valist = gimple_call_arg (t, 0);
+             struct constraint_expr rhs, *lhsp;
+             unsigned i;
+             /* The va_list gets access to pointers in variadic
+                arguments.  */
+             fi = lookup_vi_for_tree (cfun->decl);
+             gcc_assert (fi != NULL);
+             get_constraint_for (valist, &lhsc);
+             do_deref (&lhsc);
+             rhs = get_function_part_constraint (fi, ~0);
+             rhs.type = ADDRESSOF;
+             FOR_EACH_VEC_ELT (ce_s, lhsc, i, lhsp)
+                 process_constraint (new_constraint (*lhsp, rhs));
+             VEC_free (ce_s, heap, lhsc);
+             /* va_list is clobbered.  */
+             make_constraint_to (get_call_clobber_vi (t)->id, valist);
+             return true;
            }
-         /* printf-style functions may have hooks to set pointers to
-            point to somewhere into the generated string.  Leave them
-            for a later excercise...  */
-         default:
-           /* Fallthru to general call handling.  */;
-         }
-      if (!in_ipa_mode
-         || gimple_call_internal_p (t)
-         || (fndecl
-             && (!(fi = lookup_vi_for_tree (fndecl))
-                 || !fi->is_fn_info)))
+         break;
+       }
+      /* va_end doesn't have any effect that matters.  */
+      case BUILT_IN_VA_END:
+       return true;
+      /* Alternate return.  Simply give up for now.  */
+      case BUILT_IN_RETURN:
        {
-         VEC(ce_s, heap) *rhsc = NULL;
-         int flags = gimple_call_flags (t);
-
-         /* Const functions can return their arguments and addresses
-            of global memory but not of escaped memory.  */
-         if (flags & (ECF_CONST|ECF_NOVOPS))
+         fi = NULL;
+         if (!in_ipa_mode
+             || !(fi = get_vi_for_tree (cfun->decl)))
+           make_constraint_from (get_varinfo (escaped_id), anything_id);
+         else if (in_ipa_mode
+                  && fi != NULL)
            {
-             if (gimple_call_lhs (t))
-               handle_const_call (t, &rhsc);
+             struct constraint_expr lhs, rhs;
+             lhs = get_function_part_constraint (fi, fi_result);
+             rhs.var = anything_id;
+             rhs.offset = 0;
+             rhs.type = SCALAR;
+             process_constraint (new_constraint (lhs, rhs));
            }
-         /* Pure functions can return addresses in and of memory
-            reachable from their arguments, but they are not an escape
-            point for reachable memory of their arguments.  */
-         else if (flags & (ECF_PURE|ECF_LOOPING_CONST_OR_PURE))
-           handle_pure_call (t, &rhsc);
-         else
-           handle_rhs_call (t, &rhsc);
+         return true;
+       }
+      /* printf-style functions may have hooks to set pointers to
+        point to somewhere into the generated string.  Leave them
+        for a later excercise...  */
+      default:
+       /* Fallthru to general call handling.  */;
+      }
+
+  return false;
+}
+
+/* Create constraints for the call T.  */
+
+static void
+find_func_aliases_for_call (gimple t)
+{
+  tree fndecl = gimple_call_fndecl (t);
+  VEC(ce_s, heap) *lhsc = NULL;
+  VEC(ce_s, heap) *rhsc = NULL;
+  varinfo_t fi;
+
+  if (fndecl != NULL_TREE
+      && DECL_BUILT_IN (fndecl)
+      && find_func_aliases_for_builtin_call (t))
+    return;
+
+  if (!in_ipa_mode
+      || gimple_call_internal_p (t)
+      || (fndecl
+         && (!(fi = lookup_vi_for_tree (fndecl))
+             || !fi->is_fn_info)))
+    {
+      VEC(ce_s, heap) *rhsc = NULL;
+      int flags = gimple_call_flags (t);
+
+      /* Const functions can return their arguments and addresses
+        of global memory but not of escaped memory.  */
+      if (flags & (ECF_CONST|ECF_NOVOPS))
+       {
          if (gimple_call_lhs (t))
-           handle_lhs_call (t, gimple_call_lhs (t), flags, rhsc, fndecl);
-         VEC_free (ce_s, heap, rhsc);
+           handle_const_call (t, &rhsc);
        }
+      /* Pure functions can return addresses in and of memory
+        reachable from their arguments, but they are not an escape
+        point for reachable memory of their arguments.  */
+      else if (flags & (ECF_PURE|ECF_LOOPING_CONST_OR_PURE))
+       handle_pure_call (t, &rhsc);
       else
-       {
-         tree lhsop;
-         unsigned j;
+       handle_rhs_call (t, &rhsc);
+      if (gimple_call_lhs (t))
+       handle_lhs_call (t, gimple_call_lhs (t), flags, rhsc, fndecl);
+      VEC_free (ce_s, heap, rhsc);
+    }
+  else
+    {
+      tree lhsop;
+      unsigned j;
 
-         fi = get_fi_for_callee (t);
+      fi = get_fi_for_callee (t);
 
-         /* Assign all the passed arguments to the appropriate incoming
-            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 (VEC_length (ce_s, rhsc) != 0)
-               {
-                 rhsp = VEC_last (ce_s, rhsc);
-                 process_constraint (new_constraint (lhs, *rhsp));
-                 VEC_pop (ce_s, rhsc);
-               }
-           }
+      /* Assign all the passed arguments to the appropriate incoming
+        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);
 
-         /* If we are returning a value, assign it to the result.  */
-         lhsop = gimple_call_lhs (t);
-         if (lhsop)
+         get_constraint_for_rhs (arg, &rhsc);
+         lhs = get_function_part_constraint (fi, fi_parm_base + j);
+         while (VEC_length (ce_s, rhsc) != 0)
            {
-             struct constraint_expr rhs;
-             struct constraint_expr *lhsp;
-
-             get_constraint_for (lhsop, &lhsc);
-             rhs = get_function_part_constraint (fi, fi_result);
-             if (fndecl
-                 && DECL_RESULT (fndecl)
-                 && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
-               {
-                 VEC(ce_s, heap) *tem = NULL;
-                 VEC_safe_push (ce_s, heap, tem, &rhs);
-                 do_deref (&tem);
-                 rhs = *VEC_index (ce_s, tem, 0);
-                 VEC_free(ce_s, heap, tem);
-               }
-             FOR_EACH_VEC_ELT (ce_s, lhsc, j, lhsp)
-               process_constraint (new_constraint (*lhsp, rhs));
+             rhsp = VEC_last (ce_s, rhsc);
+             process_constraint (new_constraint (lhs, *rhsp));
+             VEC_pop (ce_s, rhsc);
            }
+       }
 
-         /* If we pass the result decl by reference, honor that.  */
-         if (lhsop
-             && fndecl
+      /* If we are returning a value, assign it to the result.  */
+      lhsop = gimple_call_lhs (t);
+      if (lhsop)
+       {
+         struct constraint_expr rhs;
+         struct constraint_expr *lhsp;
+
+         get_constraint_for (lhsop, &lhsc);
+         rhs = get_function_part_constraint (fi, fi_result);
+         if (fndecl
              && DECL_RESULT (fndecl)
              && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
            {
-             struct constraint_expr lhs;
-             struct constraint_expr *rhsp;
-
-             get_constraint_for_address_of (lhsop, &rhsc);
-             lhs = get_function_part_constraint (fi, fi_result);
-             FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
-               process_constraint (new_constraint (lhs, *rhsp));
-             VEC_free (ce_s, heap, rhsc);
+             VEC(ce_s, heap) *tem = NULL;
+             VEC_safe_push (ce_s, heap, tem, &rhs);
+             do_deref (&tem);
+             rhs = *VEC_index (ce_s, tem, 0);
+             VEC_free(ce_s, heap, tem);
            }
+         FOR_EACH_VEC_ELT (ce_s, lhsc, j, lhsp)
+             process_constraint (new_constraint (*lhsp, rhs));
+       }
 
-         /* If we use a static chain, pass it along.  */
-         if (gimple_call_chain (t))
-           {
-             struct constraint_expr lhs;
-             struct constraint_expr *rhsp;
+      /* If we pass the result decl by reference, honor that.  */
+      if (lhsop
+         && fndecl
+         && DECL_RESULT (fndecl)
+         && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
+       {
+         struct constraint_expr lhs;
+         struct constraint_expr *rhsp;
 
-             get_constraint_for (gimple_call_chain (t), &rhsc);
-             lhs = get_function_part_constraint (fi, fi_static_chain);
-             FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
-               process_constraint (new_constraint (lhs, *rhsp));
+         get_constraint_for_address_of (lhsop, &rhsc);
+         lhs = get_function_part_constraint (fi, fi_result);
+         FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
+             process_constraint (new_constraint (lhs, *rhsp));
+         VEC_free (ce_s, heap, rhsc);
+       }
+
+      /* If we use a static chain, pass it along.  */
+      if (gimple_call_chain (t))
+       {
+         struct constraint_expr lhs;
+         struct constraint_expr *rhsp;
+
+         get_constraint_for (gimple_call_chain (t), &rhsc);
+         lhs = get_function_part_constraint (fi, fi_static_chain);
+         FOR_EACH_VEC_ELT (ce_s, rhsc, j, rhsp)
+             process_constraint (new_constraint (lhs, *rhsp));
+       }
+    }
+}
+
+/* Walk statement T setting up aliasing constraints according to the
+   references found in T.  This function is the main part of the
+   constraint builder.  AI points to auxiliary alias information used
+   when building alias sets and computing alias grouping heuristics.  */
+
+static void
+find_func_aliases (gimple origt)
+{
+  gimple t = origt;
+  VEC(ce_s, heap) *lhsc = NULL;
+  VEC(ce_s, heap) *rhsc = NULL;
+  struct constraint_expr *c;
+  varinfo_t fi;
+
+  /* Now build constraints expressions.  */
+  if (gimple_code (t) == GIMPLE_PHI)
+    {
+      size_t i;
+      unsigned int j;
+
+      /* For a phi node, assign all the arguments to
+        the result.  */
+      get_constraint_for (gimple_phi_result (t), &lhsc);
+      for (i = 0; i < gimple_phi_num_args (t); i++)
+       {
+         tree strippedrhs = PHI_ARG_DEF (t, i);
+
+         STRIP_NOPS (strippedrhs);
+         get_constraint_for_rhs (gimple_phi_arg_def (t, i), &rhsc);
+
+         FOR_EACH_VEC_ELT (ce_s, lhsc, j, c)
+           {
+             struct constraint_expr *c2;
+             while (VEC_length (ce_s, rhsc) > 0)
+               {
+                 c2 = VEC_last (ce_s, rhsc);
+                 process_constraint (new_constraint (*c, *c2));
+                 VEC_pop (ce_s, rhsc);
+               }
            }
        }
     }
+  /* In IPA mode, we need to generate constraints to pass call
+     arguments through their calls.   There are two cases,
+     either a GIMPLE_CALL returning a value, or just a plain
+     GIMPLE_CALL when we are not.
+
+     In non-ipa mode, we need to generate constraints for each
+     pointer passed by address.  */
+  else if (is_gimple_call (t))
+    find_func_aliases_for_call (t);
+    
   /* Otherwise, just a regular assignment statement.  Only care about
      operations with pointer result, others are dealt with as escape
      points if they have pointer operands.  */