* tree-dfa.c (find_hidden_use_vars): Also look inside the

        PENDING_SIZES list for hidden uses.
        * tree-optimize.c (tree_rest_of_compilation): Expand used variables
        before setting up parameters.
        * tree-ssa-copyrename.c (rename_ssa_copies): Do nothing for copies
        where the LHS has a hidden use.


git-svn-id: https://gcc.gnu.org/svn/gcc/branches/tree-ssa-20020619-branch@79692 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 40 insertions, 7 deletions

diff --git a/gcc/ChangeLog.tree-ssa b/gcc/ChangeLog.tree-ssa
index a91a9190733..2f6f7fb3a0f 100644
--- a/gcc/ChangeLog.tree-ssa
+++ b/gcc/ChangeLog.tree-ssa
@@ -1,3 +1,12 @@
+2003-03-19  Jeff Law  <law@redhat.com>
+
+	* tree-dfa.c (find_hidden_use_vars): Also look inside the
+	PENDING_SIZES list for hidden uses.
+	* tree-optimize.c (tree_rest_of_compilation): Expand used variables
+	before setting up parameters.
+	* tree-ssa-copyrename.c (rename_ssa_copies): Do nothing for copies
+	where the LHS has a hidden use.
+
 2004-03-18  Diego Novillo  <dnovillo@redhat.com>
 
 	* Makefile.in (TREE_FLOW_H): Reformat.
diff --git a/gcc/tree-dfa.c b/gcc/tree-dfa.c
index 8d50ccbaa5f..4caa26b5aaa 100644
--- a/gcc/tree-dfa.c
+++ b/gcc/tree-dfa.c
@@ -1000,7 +1000,7 @@ get_virtual_var (tree var)
 static void
 find_hidden_use_vars (tree block)
 {
-  tree sub, decl;
+  tree sub, decl, tem;
 
   /* Check all the arrays declared in the block for VLAs.
 
@@ -1015,6 +1015,21 @@ find_hidden_use_vars (tree block)
   /* Now repeat the search in any sub-blocks.  */
   for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
     find_hidden_use_vars (sub);
+
+  /* A VLA parameter may use a variable which as set from another
+     parameter to declare the size of the VLA.  We need to mark the
+     variable as having a hidden use since it is used to declare the
+     VLA parameter and that declaration is not seen by the SSA code. 
+
+     Note get_pending_sizes clears the PENDING_SIZES chain, so we
+     must restore it. */
+  tem = get_pending_sizes ();
+  put_pending_sizes (tem);
+  for (; tem; tem = TREE_CHAIN (tem))
+    {
+      int inside_vla = 1;
+      walk_tree (&TREE_VALUE (tem), find_hidden_use_vars_r, &inside_vla, NULL);
+    }
 }
 
 /* Callback for walk_tree used by find_hidden_use_vars to analyze each 
diff --git a/gcc/tree-optimize.c b/gcc/tree-optimize.c
index e7778cff9f1..6af4b029389 100644
--- a/gcc/tree-optimize.c
+++ b/gcc/tree-optimize.c
@@ -534,12 +534,15 @@ tree_rest_of_compilation (tree fndecl, bool nested_p)
     walk_tree (&TREE_TYPE (fndecl), set_save_expr_context, fndecl,
 	       NULL);
 
+  /* Expand the variables recorded during gimple lowering.  This must
+     occur before the call to expand_function_start to ensure that
+     all used variables are expanded before we expand anything on the
+     PENDING_SIZES list.  */
+  expand_used_vars ();
+
   /* Set up parameters and prepare for return, for the function.  */
   expand_function_start (fndecl, 0);
 
-  /* Expand the variables recorded during gimple lowering.  */
-  expand_used_vars ();
-
   /* Allow language dialects to perform special processing.  */
   (*lang_hooks.rtl_expand.start) ();
 
diff --git a/gcc/tree-ssa-copyrename.c b/gcc/tree-ssa-copyrename.c
index 8451d0e83a9..8251158f1e4 100644
--- a/gcc/tree-ssa-copyrename.c
+++ b/gcc/tree-ssa-copyrename.c
@@ -274,9 +274,13 @@ rename_ssa_copies (void)
         {
           int i;
 	  tree res = PHI_RESULT (phi);
-	  /* Dont process virtual SSA_NAMES.  */
-	  if (!is_gimple_reg (SSA_NAME_VAR (res)))
+
+	  /* Do not process virtual SSA_NAMES or variables which have
+	     hidden uses.  */
+	  if (!is_gimple_reg (SSA_NAME_VAR (res))
+	      || has_hidden_use (SSA_NAME_VAR (res)))
 	    continue;
+
           for (i = 0; i < PHI_NUM_ARGS (phi); i++)
             {
               tree arg = PHI_ARG_DEF (phi, i);
@@ -294,7 +298,9 @@ rename_ssa_copies (void)
 	      tree lhs = TREE_OPERAND (stmt, 0);
 	      tree rhs = TREE_OPERAND (stmt, 1);
 
-              if (TREE_CODE (lhs) == SSA_NAME && TREE_CODE (rhs) == SSA_NAME)
+              if (TREE_CODE (lhs) == SSA_NAME
+		  && !has_hidden_use (SSA_NAME_VAR (lhs))
+		  && TREE_CODE (rhs) == SSA_NAME)
 		copy_rename_partition_coalesce (map, lhs, rhs, debug);
 	    }
 	}