PR fortran/23516

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-loop-niter.c

diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
index a8e4737..b720e19 100644 (file)
--- a/gcc/tree-ssa-loop-niter.c
+++ b/gcc/tree-ssa-loop-niter.c
@@ -634,11 +634,15 @@ expand_simple_operations (tree expr)
 {
   unsigned i, n;
   tree ret = NULL_TREE, e, ee, stmt;
-  enum tree_code code = TREE_CODE (expr);
+  enum tree_code code;
+
+  if (expr == NULL_TREE)
+    return expr;
 
   if (is_gimple_min_invariant (expr))
     return expr;
 
+  code = TREE_CODE (expr);
   if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
     {
       n = TREE_CODE_LENGTH (code);
@@ -1434,10 +1438,10 @@ infer_loop_bounds_from_undefined (struct loop *loop)
                /* For each array access, analyze its access function
                   and record a bound on the loop iteration domain.  */
                if (TREE_CODE (op1) == ARRAY_REF)
-                 analyze_array (stmt, op1, true);
+                 estimate_iters_using_array (stmt, op1);
 
                if (TREE_CODE (op0) == ARRAY_REF)
-                 analyze_array (stmt, op0, false);
+                 estimate_iters_using_array (stmt, op0);
 
                /* For each signed type variable in LOOP, analyze its
                   scalar evolution and record a bound of the loop
@@ -1460,7 +1464,9 @@ infer_loop_bounds_from_undefined (struct loop *loop)
                    if (init == NULL_TREE
                        || step == NULL_TREE
                        || TREE_CODE (init) != INTEGER_CST
-                       || TREE_CODE (step) != INTEGER_CST)
+                       || TREE_CODE (step) != INTEGER_CST
+                       || TYPE_MIN_VALUE (type) == NULL_TREE
+                       || TYPE_MAX_VALUE (type) == NULL_TREE)
                      break;
 
                    utype = unsigned_type_for (type);
@@ -1486,7 +1492,7 @@ infer_loop_bounds_from_undefined (struct loop *loop)
                for (args = TREE_OPERAND (stmt, 1); args;
                     args = TREE_CHAIN (args))
                  if (TREE_CODE (TREE_VALUE (args)) == ARRAY_REF)
-                   analyze_array (stmt, TREE_VALUE (args), true);
+                   estimate_iters_using_array (stmt, TREE_VALUE (args));
 
                break;
              }
@@ -1821,7 +1827,8 @@ scev_probably_wraps_p (tree type, tree base, tree step,
   struct nb_iter_bound *bound;
   tree delta, step_abs;
   tree unsigned_type, valid_niter;
-  tree base_plus_step;
+  tree base_plus_step, bpsps;
+  int cps, cpsps;
 
   /* FIXME: The following code will not be used anymore once
      http://gcc.gnu.org/ml/gcc-patches/2005-06/msg02025.html is
@@ -1854,7 +1861,9 @@ scev_probably_wraps_p (tree type, tree base, tree step,
        }
     }
 
-  if (TREE_CODE (base) == REAL_CST
+  if (chrec_contains_undetermined (base)
+      || chrec_contains_undetermined (step)
+      || TREE_CODE (base) == REAL_CST
       || TREE_CODE (step) == REAL_CST)
     {
       *unknown_max = true;
@@ -1863,7 +1872,17 @@ scev_probably_wraps_p (tree type, tree base, tree step,
 
   *unknown_max = false;
   base_plus_step = fold_build2 (PLUS_EXPR, type, base, step);
-  switch (compare_trees (base_plus_step, base))
+  bpsps = fold_build2 (PLUS_EXPR, type, base_plus_step, step);
+  cps = compare_trees (base_plus_step, base);
+  cpsps = compare_trees (bpsps, base_plus_step);
+
+  /* Check that the sequence is not wrapping in the first step: it
+     should have the same monotonicity for the first two steps.  See
+     PR23410.  */
+  if (cps != cpsps)
+    return true;
+
+  switch (cps)
     {
     case -1:
       {
@@ -1965,7 +1984,13 @@ tree
 convert_step (struct loop *loop, tree new_type, tree base, tree step,
              tree at_stmt)
 {
-  tree base_type = TREE_TYPE (base);
+  tree base_type;
+
+  if (chrec_contains_undetermined (base)
+      || chrec_contains_undetermined (step))
+    return NULL_TREE;
+
+  base_type = TREE_TYPE (base);
 
   /* When not using wrapping arithmetic, signed types don't wrap.  */
   if (!flag_wrapv && !TYPE_UNSIGNED (base_type))