re PR middle-end/44784 (Failed to build 403.gcc in SPEC CPU 2006)

2010-07-05  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/44784
	* tree-ssa-pre.c (bitmap_find_leader): Fix dominance check
	for inserted stmts.
	(find_or_generate_expression): Fix SCCVN insertion check.

	* gcc.c-torture/compile/pr44784.c: New testcase.

From-SVN: r161829

gcc/ChangeLog

+2010-07-05  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/44784
+	* tree-ssa-pre.c (bitmap_find_leader): Fix dominance check
+	for inserted stmts.
+	(find_or_generate_expression): Fix SCCVN insertion check.
+
 2010-07-05  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* config/rs6000/e500crtsavg64gprctr.asm: Correct done label name.

gcc/testsuite/ChangeLog

+2010-07-05  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/44784
+	* gcc.c-torture/compile/pr44784.c: New testcase.
+
 2010-07-05  Ira Rosen  <irar@il.ibm.com>
 
 	* gcc.dg/vect/costmodel/i386/costmodel-fast-math-vect-pr29925.c:

gcc/testsuite/gcc.c-torture/compile/pr44784.c

+typedef struct rtx_def *rtx;
+enum rtx_code { SUBREG };
+typedef union rtunion_def {
+    long rtint;
+    unsigned long rtuint;
+    rtx rtx;
+} rtunion;
+struct rtx_def {
+    enum rtx_code code: 8;
+    rtunion fld[1];
+};
+typedef struct simple_bitmap_def {
+    unsigned long long elms[1];
+} *sbitmap;
+struct df_link {
+    struct df_link *next;
+    rtx reg;
+};
+typedef enum { UNDEFINED,   CONSTANT,   VARYING } latticevalue;
+typedef struct {
+    latticevalue lattice_val;
+} value;
+static value *values;
+static sbitmap ssa_edges;
+void defs_to_varying (struct df_link *start)
+{
+  struct df_link *currdef;
+  for (currdef = start;
+       currdef;
+       currdef = currdef->next)
+    {
+      rtx reg = currdef->reg;
+      if (values[(reg->code == SUBREG
+		  ? reg->fld[0].rtx
+		  : reg)->fld[0].rtuint].lattice_val != VARYING)
+	ssa_edges->elms [(reg->code == SUBREG
+			  ? reg->fld[0].rtx
+			  : reg)->fld[0].rtuint / 64]
+	    |= ((unsigned long long) 1
+		<< (reg->code == SUBREG
+		    ? reg->fld[0].rtx
+		    : reg)->fld[0].rtuint % 64);
+      values[(reg->code == SUBREG
+	      ? reg->fld[0].rtx
+	      : reg)->fld[0].rtuint].lattice_val = VARYING;
+    }
+}

gcc/tree-ssa-pre.c

@@ -1955,7 +1955,10 @@ bitmap_find_leader (bitmap_set_t set, unsigned int val, gimple stmt)
 	      gimple def_stmt = SSA_NAME_DEF_STMT (PRE_EXPR_NAME (val));
 	      if (gimple_code (def_stmt) != GIMPLE_PHI
 		  && gimple_bb (def_stmt) == gimple_bb (stmt)
-		  && gimple_uid (def_stmt) >= gimple_uid (stmt))
+		  /* PRE insertions are at the end of the basic-block
+		     and have UID 0.  */
+		  && (gimple_uid (def_stmt) == 0
+		      || gimple_uid (def_stmt) >= gimple_uid (stmt)))
 		continue;
 	    }
 	  return val;
@@ -3021,9 +3024,10 @@ find_or_generate_expression (basic_block block, pre_expr expr,
     }
 
   /* If it's still NULL, it must be a complex expression, so generate
-     it recursively.  Not so for FRE though.  */
+     it recursively.  Not so if inserting expressions for values generated
+     by SCCVN.  */
   if (genop == NULL
-      && !in_fre)
+      && !domstmt)
     {
       bitmap_set_t exprset;
       unsigned int lookfor = get_expr_value_id (expr);