tree-data-ref.c (analyze_offset): Add a return value (bool) to indicate success/failure of the analysis.

* tree-data-ref.c (analyze_offset): Add a return value (bool) to
	indicate success/failure of the analysis. Add negation to subtrahend
	in case of subtraction. Fail if both operands contain constants.
	(create_data_ref): Fail if analyze_offset fails.

From-SVN: r122817

gcc/ChangeLog

@@ -1,3 +1,10 @@
+2007-03-11  Ira Rosen  <irar@il.ibm.com>
+
+	* tree-data-ref.c (analyze_offset): Add a return value (bool) to 
+	indicate success/failure of the analysis. Add negation to subtrahend
+	in case of subtraction. Fail if both operands contain constants.
+	(create_data_ref): Fail if analyze_offset fails.
+
 2007-03-11  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386.md (frndintxf2): Rename to ...

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2007-03-11  Ira Rosen  <irar@il.ibm.com>
+
+	PR tree-optimization/29925
+	* gcc.dg/vect/fast-math-vect-pr29925.c: New test.
+
 2007-03-10  Mark Mitchell  <mark@codesourcery.com>
 
 	PR c++/30274

gcc/testsuite/gcc.dg/vect/fast-math-vect-pr29925.c

@@ -0,0 +1,39 @@
+/* { dg-require-effective-target vect_float } */
+
+#include <stdlib.h>
+#include "tree-vect.h"
+
+void interp_pitch(float *exc, float *interp, int pitch, int len)
+{
+   int i,k;
+   int maxj;
+
+   maxj=3;
+   for (i=0;i<len;i++)
+   {
+      float tmp = 0;
+      for (k=0;k<7;k++)
+      {
+         tmp += exc[i-pitch+k+maxj-6];
+      }
+      interp[i] = tmp;
+   }
+}
+
+int main()
+{
+   float *exc = calloc(126,sizeof(float));
+   float *interp = calloc(80,sizeof(float));
+   int pitch = -35;
+
+   check_vect ();
+
+   interp_pitch(exc, interp, pitch, 80);
+   free(exc);
+   free(interp);
+   return 0;
+}
+
+/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+

gcc/tree-data-ref.c

@@ -1835,7 +1835,7 @@ object_analysis (tree memref, tree stmt, bool is_read,
    Extract INVARIANT and CONSTANT parts from OFFSET. 
 
 */
-static void 
+static bool 
 analyze_offset (tree offset, tree *invariant, tree *constant)
 {
   tree op0, op1, constant_0, constant_1, invariant_0, invariant_1;
@@ -1851,23 +1851,36 @@ analyze_offset (tree offset, tree *invariant, tree *constant)
 	*constant = offset;
       else
 	*invariant = offset;
-      return;
+      return true;
     }
 
   op0 = TREE_OPERAND (offset, 0);
   op1 = TREE_OPERAND (offset, 1);
 
   /* Recursive call with the operands.  */
-  analyze_offset (op0, &invariant_0, &constant_0);
-  analyze_offset (op1, &invariant_1, &constant_1);
+  if (!analyze_offset (op0, &invariant_0, &constant_0)
+      || !analyze_offset (op1, &invariant_1, &constant_1))
+    return false;
 
-  /* Combine the results.  */
+  /* Combine the results. Add negation to the subtrahend in case of 
+     subtraction.  */
+  if (constant_0 && constant_1)
+    return false;
   *constant = constant_0 ? constant_0 : constant_1;
+  if (code == MINUS_EXPR && constant_1)
+    *constant = fold_build1 (NEGATE_EXPR, TREE_TYPE (*constant), *constant);
+
   if (invariant_0 && invariant_1)
     *invariant = 
       fold_build2 (code, TREE_TYPE (invariant_0), invariant_0, invariant_1);
   else
-    *invariant = invariant_0 ? invariant_0 : invariant_1;
+    {
+      *invariant = invariant_0 ? invariant_0 : invariant_1;
+      if (code == MINUS_EXPR && invariant_1)
+        *invariant = 
+           fold_build1 (NEGATE_EXPR, TREE_TYPE (*invariant), *invariant);
+    }
+  return true;
 }
 
 /* Free the memory used by the data reference DR.  */
@@ -1941,7 +1954,17 @@ create_data_ref (tree memref, tree stmt, bool is_read)
   STRIP_NOPS (offset);
   if (offset != orig_offset)
     type = TREE_TYPE (orig_offset);
-  analyze_offset (offset, &invariant, &constant);
+  if (!analyze_offset (offset, &invariant, &constant))
+    {
+      if (dump_file && (dump_flags & TDF_DETAILS))
+        {
+          fprintf (dump_file, "\ncreate_data_ref: failed to analyze dr's");
+          fprintf (dump_file, " offset for ");
+          print_generic_expr (dump_file, memref, TDF_SLIM);
+          fprintf (dump_file, "\n");
+        }
+      return NULL;
+    }
   if (type && invariant)
     invariant = fold_convert (type, invariant);