[multiple changes]

2004-06-11  Steven Bosscher <stevenb@suse.de>

	* tree-ssa-dce.c (mark_control_dependent_edges_necessary):
	Don't try to mark anything control dependent on the entry or
	exit blocks.

2004-06-11  Daniel Berlin  <dberlin@dberlin.org>

	Fix Bug 15899
	Fix Bug 15460
	* tree.h (SSA_NAME_VALUE): New macro.
	(struct tree_ssa_name): Add value_handle member.
	* tree-ssa-pre.c: Replaced.
	* tree-flow.h (tree_ann_type): Add CST_ANN, EXPR_ANN.
	(struct cst_ann_d): New.
	(struct expr_ann_d): New.
	(union tree_ann_d): Add cst_ann, expr_ann.
	* tree-dfa.c (create_cst_ann): New function.
	(create_expr_ann): Ditto.
	* tree-flow-inline.h (cst_ann): New function.
	(expr_ann): Ditto.
	(get_cst_ann): Ditto.
	(get_expr_ann): Ditto..

From-SVN: r83010

gcc/ChangeLog

@@ -1,3 +1,27 @@
+2004-06-11  Steven Bosscher <stevenb@suse.de>
+
+	* tree-ssa-dce.c (mark_control_dependent_edges_necessary):
+	Don't try to mark anything control dependent on the entry or
+	exit blocks.
+
+2004-06-11  Daniel Berlin  <dberlin@dberlin.org>
+	
+	Fix Bug 15899
+	Fix Bug 15460
+	* tree.h (SSA_NAME_VALUE): New macro.
+	(struct tree_ssa_name): Add value_handle member.
+	* tree-ssa-pre.c: Replaced.
+	* tree-flow.h (tree_ann_type): Add CST_ANN, EXPR_ANN.
+	(struct cst_ann_d): New.
+	(struct expr_ann_d): New.
+	(union tree_ann_d): Add cst_ann, expr_ann.
+	* tree-dfa.c (create_cst_ann): New function.
+	(create_expr_ann): Ditto.
+	* tree-flow-inline.h (cst_ann): New function.
+	(expr_ann): Ditto.
+	(get_cst_ann): Ditto.
+	(get_expr_ann): Ditto..
+
 2004-06-11  John David Anglin  <dave.anglin@nrc-cnrc.gc.ca>
 
 	* pa.c (pa_hpux_init_libfunc): Add support for unord_optab.

gcc/testsuite/gcc.c-torture/compile/20040611-1.c

@@ -0,0 +1,8 @@
+/* This would cause PRE load motion to generate invalid code and ICE */
+void foo (char *name)
+{
+  if (*name)
+    name ++;
+  while (name[0]);
+  asm ("" : "=r" (name));
+}

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

@@ -16,4 +16,4 @@ int main(int argc, char **argv)
 }
 /* We should eliminate one evaluation of b + c along the main path, 
    causing one reload. */
-/* { dg-final { scan-tree-dump-times "Reloads:1" 1 "pre"} } */
+/* { dg-final { scan-tree-dump-times "Eliminated:1" 1 "pre"} } */

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

@@ -17,4 +17,4 @@ int motion_test1(int data, int data_0, int data_3, int v)
 }
 /* We should eliminate one computation of data_0 + data_3 along the 
    main path, causing one reload. */
-/* { dg-final { scan-tree-dump-times "Reloads:1" 1 "pre"} } */
+/* { dg-final { scan-tree-dump-times "Eliminated:1" 1 "pre"} } */

gcc/tree-dfa.c

@@ -463,6 +463,52 @@ create_stmt_ann (tree t)
 }
 
 
+/* Create a new annotation for a constant T.  */
+
+cst_ann_t
+create_cst_ann (tree t)
+{
+  cst_ann_t ann;
+
+#if defined ENABLE_CHECKING
+  if (t == NULL_TREE
+      || (t->common.ann
+	  && t->common.ann->common.type != CST_ANN))
+    abort ();
+#endif
+
+  ann = ggc_alloc (sizeof (*ann));
+  memset ((void *) ann, 0, sizeof (*ann));
+
+  ann->common.type = CST_ANN;
+  t->common.ann = (tree_ann) ann;
+
+  return ann;
+}
+
+/* Create a new annotation for an expression T.  */
+
+expr_ann_t
+create_expr_ann (tree t)
+{
+  expr_ann_t ann;
+
+#if defined ENABLE_CHECKING
+  if (t == NULL_TREE
+      || (t->common.ann
+	  && t->common.ann->common.type != EXPR_ANN))
+    abort ();
+#endif
+
+  ann = ggc_alloc (sizeof (*ann));
+  memset ((void *) ann, 0, sizeof (*ann));
+
+  ann->common.type = EXPR_ANN;
+  t->common.ann = (tree_ann) ann;
+
+  return ann;
+}
+
 /* Build a temporary.  Make sure and register it to be renamed.  */
 
 tree

gcc/tree-flow-inline.h

@@ -46,6 +46,47 @@ get_var_ann (tree var)
   return (ann) ? ann : create_var_ann (var);
 }
 
+
+static inline cst_ann_t
+cst_ann (tree t)
+{
+#if defined ENABLE_CHECKING
+  if (TREE_CODE_CLASS (TREE_CODE (t)) != 'c'
+      || (t->common.ann
+	  && t->common.ann->common.type != CST_ANN))
+    abort ();
+#endif
+
+  return (cst_ann_t) t->common.ann;
+}
+
+static inline cst_ann_t
+get_cst_ann (tree var)
+{
+  cst_ann_t ann = cst_ann (var);
+  return (ann) ? ann : create_cst_ann (var);
+}
+
+static inline expr_ann_t
+expr_ann (tree t)
+{
+#if defined ENABLE_CHECKING
+  if (!EXPR_P (t)
+      || (t->common.ann
+	  && t->common.ann->common.type != EXPR_ANN))
+    abort ();
+#endif
+
+  return (expr_ann_t) t->common.ann;
+}
+
+static inline expr_ann_t
+get_expr_ann (tree var)
+{
+  expr_ann_t ann = expr_ann (var);
+  return (ann) ? ann : create_expr_ann (var);
+}
+
 static inline stmt_ann_t
 stmt_ann (tree t)
 {

gcc/tree-flow.h

@@ -40,12 +40,15 @@ typedef struct basic_block_def *basic_block;
 /*---------------------------------------------------------------------------
 		   Tree annotations stored in tree_common.ann
 ---------------------------------------------------------------------------*/
-enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, STMT_ANN };
+enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, CST_ANN, EXPR_ANN, STMT_ANN };
 
 struct tree_ann_common_d GTY(())
 {
   /* Annotation type.  */
   enum tree_ann_type type;
+
+  /* The value handle for this expression.  Used by GVN-PRE.  */
+  tree GTY((skip)) value_handle;
 };
 
 /* It is advantageous to avoid things like life analysis for variables which
@@ -164,6 +167,11 @@ struct var_ann_d GTY(())
      live at the same time and this can happen for each call to the
      dominator optimizer.  */
   tree current_def;
+
+  /* The set of expressions represented by this variable if it is a
+     value handle.  This is used by GVN-PRE.  */
+  PTR GTY ((skip)) expr_set;
+  
 };
 
 
@@ -256,17 +264,38 @@ struct stmt_ann_d GTY(())
 };
 
 
+struct cst_ann_d GTY (())
+{
+  struct tree_ann_common_d common;
+  
+};
+
+struct expr_ann_d GTY(())
+{
+  struct tree_ann_common_d common;
+  
+};
+
+
 union tree_ann_d GTY((desc ("ann_type ((tree_ann)&%h)")))
 {
   struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
   struct var_ann_d GTY((tag ("VAR_ANN"))) decl;
+  struct expr_ann_d GTY((tag ("EXPR_ANN"))) expr;
+  struct cst_ann_d GTY((tag ("CST_ANN"))) cst;
   struct stmt_ann_d GTY((tag ("STMT_ANN"))) stmt;
 };
 
 typedef union tree_ann_d *tree_ann;
 typedef struct var_ann_d *var_ann_t;
 typedef struct stmt_ann_d *stmt_ann_t;
+typedef struct expr_ann_d *expr_ann_t;
+typedef struct cst_ann_d *cst_ann_t;
 
+static inline cst_ann_t cst_ann (tree);
+static inline cst_ann_t get_cst_ann (tree);
+static inline expr_ann_t expr_ann (tree);
+static inline expr_ann_t get_expr_ann (tree);
 static inline var_ann_t var_ann (tree);
 static inline var_ann_t get_var_ann (tree);
 static inline stmt_ann_t stmt_ann (tree);
@@ -464,6 +493,8 @@ extern void dump_generic_bb (FILE *, basic_block, int, int);
 
 /* In tree-dfa.c  */
 extern var_ann_t create_var_ann (tree);
+extern cst_ann_t create_cst_ann (tree);
+extern expr_ann_t create_expr_ann (tree);
 extern stmt_ann_t create_stmt_ann (tree);
 extern tree create_phi_node (tree, basic_block);
 extern void add_phi_arg (tree *, tree, edge);
@@ -567,6 +598,12 @@ extern bool tree_can_throw_internal (tree);
 extern bool tree_can_throw_external (tree);
 extern void add_stmt_to_eh_region (tree, int);
 
+/* In tree-ssa-pre.c */
+tree get_value_handle (tree);
+void set_value_handle (tree, tree);
+void debug_value_expressions (tree);
+void print_value_expressions (FILE *, tree);
+
 #include "tree-flow-inline.h"
 
 #endif /* _TREE_FLOW_H  */

gcc/tree-ssa-dce.c

@@ -482,6 +482,14 @@ mark_control_dependent_edges_necessary (basic_block bb, struct edge_list *el)
 {
   int edge_number;
 
+#ifdef ENABLE_CHECKING
+  if (bb == EXIT_BLOCK_PTR)
+    abort ();
+#endif
+
+  if (bb == ENTRY_BLOCK_PTR)
+    return;
+
   EXECUTE_IF_CONTROL_DEPENDENT (bb->index, edge_number,
     {
       tree t;

gcc/tree.h

@@ -1184,6 +1184,10 @@ struct tree_exp GTY(())
 #define SSA_NAME_PTR_INFO(N) \
     SSA_NAME_CHECK (N)->ssa_name.ptr_info
 
+/* Get the value of this SSA_NAME, if available.  */
+#define SSA_NAME_VALUE(N) \
+   SSA_NAME_CHECK (N)->ssa_name.value_handle
+
 #ifndef GCC_BITMAP_H
 struct bitmap_head_def;
 #endif
@@ -1223,6 +1227,9 @@ struct tree_ssa_name GTY(())
 
   /* Pointer attributes used for alias analysis.  */
   struct ptr_info_def *ptr_info;
+
+  /* Value for SSA name used by GVN.  */ 
+  tree GTY((skip)) value_handle;
 };
 
 /* In a PHI_NODE node.  */