PR tree-optimization/32367

	* tree-chrec.h (build_polynomial_chrec): Verify that the left hand side
	of the chrec has no evolution in that loop.
	* testsuite/gcc.dg/tree-ssa/pr32367.c: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@125855 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2000145..7fcbe6c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2007-04-11  Sebastian Pop  <sebpop@gmail.com>
+
+       PR tree-optimization/32367
+       * tree-chrec.h (build_polynomial_chrec): Verify that the left hand side 
+       of the chrec has no evolution in that loop.
+       * testsuite/gcc.dg/tree-ssa/pr32367.c: New.
+
 2007-06-19  Bob Wilson  <bob.wilson@acm.org>
 
        * config/xtensa/xtensa.c: Include "df.h".

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr32367.c b/gcc/testsuite/gcc.dg/tree-ssa/pr32367.c
new file mode 100644 (file)
index 0000000..1b153b6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr32367.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+int BinomialCoefficientsInited = 0;
+int BinomialCoefficients[17 * 35];
+double Evaluate_TPat (void)
+{
+        unsigned short n, k;
+        if (BinomialCoefficientsInited == 0)
+        {
+                int *ptr = BinomialCoefficients;
+                for (n = 1; n <= 33; ++n)
+                {
+                        for (k = 1; k < n; ++k)
+                                ++ptr;
+                        *ptr = 1;
+                }
+        }
+}
+

diff --git a/gcc/tree-chrec.h b/gcc/tree-chrec.h
index e6bea92..5e9038c 100644 (file)
--- a/gcc/tree-chrec.h
+++ b/gcc/tree-chrec.h
@@ -83,6 +83,7 @@ extern bool tree_contains_chrecs (tree, int *);
 extern bool evolution_function_is_affine_multivariate_p (tree, int);
 extern bool evolution_function_is_univariate_p (tree);
 extern unsigned nb_vars_in_chrec (tree);
+extern bool evolution_function_is_invariant_p (tree, int);
 
 /* Determines whether CHREC is equal to zero.  */
 
@@ -98,6 +99,24 @@ chrec_zerop (tree chrec)
   return false;
 }
 
+/* Determines whether CHREC is a loop invariant with respect to LOOP_NUM.  
+   Set the result in RES and return true when the property can be computed.  */
+
+static inline bool
+no_evolution_in_loop_p (tree chrec, unsigned loop_num, bool *res)
+{
+  tree scev;
+  
+  if (chrec == chrec_not_analyzed_yet
+      || chrec == chrec_dont_know
+      || chrec_contains_symbols_defined_in_loop (chrec, loop_num))
+    return false;
+
+  scev = hide_evolution_in_other_loops_than_loop (chrec, loop_num);
+  *res = !tree_is_chrec (scev);
+  return true;
+}
+
 /* Build a polynomial chain of recurrence.  */
 
 static inline tree 
@@ -105,10 +124,15 @@ build_polynomial_chrec (unsigned loop_num,
                        tree left, 
                        tree right)
 {
+  bool val;
+
   if (left == chrec_dont_know
       || right == chrec_dont_know)
     return chrec_dont_know;
 
+  if (no_evolution_in_loop_p (left, loop_num, &val) && !val)
+    return chrec_dont_know;
+
   if (POINTER_TYPE_P (TREE_TYPE (left)))
     gcc_assert (sizetype == TREE_TYPE (right));
   else
@@ -140,7 +164,6 @@ evolution_function_is_constant_p (tree chrec)
     }
 }
 
-extern bool evolution_function_is_invariant_p (tree, int);
 /* Determine whether the given tree is an affine evolution function or not.  */
 
 static inline bool 
@@ -183,24 +206,6 @@ tree_does_not_contain_chrecs (tree expr)
   return !tree_contains_chrecs (expr, NULL);
 }
 
-/* Determines whether CHREC is a loop invariant with respect to LOOP_NUM.  
-   Set the result in RES and return true when the property can be computed.  */
-
-static inline bool
-no_evolution_in_loop_p (tree chrec, unsigned loop_num, bool *res)
-{
-  tree scev;
-  
-  if (chrec == chrec_not_analyzed_yet
-      || chrec == chrec_dont_know
-      || chrec_contains_symbols_defined_in_loop (chrec, loop_num))
-    return false;
-
-  scev = hide_evolution_in_other_loops_than_loop (chrec, loop_num);
-  *res = !tree_is_chrec (scev);
-  return true;
-}
-
 /* Returns the type of the chrec.  */
 
 static inline tree