analyzer: avoid use of fold_build2

Various places in the analyzer use fold_build2, test the result, then
discard it.  It's more efficient to use fold_binary, which avoids
building and GC-ing a redundant tree for the cases where folding fails.

gcc/analyzer/ChangeLog:
	* constraint-manager.cc (range::constrained_to_single_element):
	Replace fold_build2 with fold_binary.  Remove unnecessary newline.
	(constraint_manager::get_or_add_equiv_class): Replace fold_build2
	with fold_binary in two places, and remove out-of-date comment.
	(constraint_manager::eval_condition): Replace fold_build2 with
	fold_binary.
	* region-model.cc (constant_svalue::eval_condition): Likewise.
	(region_model::on_assignment): Likewise.

diff --git a/gcc/analyzer/ChangeLog b/gcc/analyzer/ChangeLog
index 5e444895101e25259bc26e2908f5f0db3662015d..4f0d0142fdc6b59e777e8657090cea137f855183 100644 (file)
--- a/gcc/analyzer/ChangeLog
+++ b/gcc/analyzer/ChangeLog
@@ -1,3 +1,14 @@
+2020-02-03  David Malcolm  <dmalcolm@redhat.com>
+
+       * constraint-manager.cc (range::constrained_to_single_element):
+       Replace fold_build2 with fold_binary.  Remove unnecessary newline.
+       (constraint_manager::get_or_add_equiv_class): Replace fold_build2
+       with fold_binary in two places, and remove out-of-date comment.
+       (constraint_manager::eval_condition): Replace fold_build2 with
+       fold_binary.
+       * region-model.cc (constant_svalue::eval_condition): Likewise.
+       (region_model::on_assignment): Likewise.
+
 2020-02-03  David Malcolm  <dmalcolm@redhat.com>
 
        PR analyzer/93544

diff --git a/gcc/analyzer/constraint-manager.cc b/gcc/analyzer/constraint-manager.cc
index 4042c50fcb7c6a9d657c72babc0488af016ab9f7..d5a6939e7144eeb30092988647ceabcff13fe5e0 100644 (file)
--- a/gcc/analyzer/constraint-manager.cc
+++ b/gcc/analyzer/constraint-manager.cc
@@ -145,10 +145,9 @@ range::constrained_to_single_element (tree *out)
   m_upper_bound.ensure_closed (true);
 
   // Are they equal?
-  tree comparison
-    = fold_build2 (EQ_EXPR, boolean_type_node,
-                  m_lower_bound.m_constant,
-                  m_upper_bound.m_constant);
+  tree comparison = fold_binary (EQ_EXPR, boolean_type_node,
+                                m_lower_bound.m_constant,
+                                m_upper_bound.m_constant);
   if (comparison == boolean_true_node)
     {
       *out = m_lower_bound.m_constant;
@@ -932,7 +931,7 @@ constraint_manager::get_or_add_equiv_class (svalue_id sid)
            && types_compatible_p (TREE_TYPE (cst),
                                   TREE_TYPE (ec->m_constant)))
          {
-           tree eq = fold_build2 (EQ_EXPR, boolean_type_node,
+           tree eq = fold_binary (EQ_EXPR, boolean_type_node,
                                   cst, ec->m_constant);
            if (eq == boolean_true_node)
              {
@@ -969,10 +968,8 @@ constraint_manager::get_or_add_equiv_class (svalue_id sid)
                 Determine the direction of the inequality, and record that
                 fact.  */
              tree lt
-               = fold_build2 (LT_EXPR, boolean_type_node,
+               = fold_binary (LT_EXPR, boolean_type_node,
                               new_ec->m_constant, other_ec.m_constant);
-             //gcc_assert (lt == boolean_true_node || lt == boolean_false_node);
-             // not true for int vs float comparisons
              if (lt == boolean_true_node)
                add_constraint_internal (new_id, CONSTRAINT_LT, other_id);
              else if (lt == boolean_false_node)
@@ -1018,7 +1015,7 @@ constraint_manager::eval_condition (equiv_class_id lhs_ec,
   if (lhs_const && rhs_const)
     {
       tree comparison
-       = fold_build2 (op, boolean_type_node, lhs_const, rhs_const);
+       = fold_binary (op, boolean_type_node, lhs_const, rhs_const);
       if (comparison == boolean_true_node)
        return tristate (tristate::TS_TRUE);
       if (comparison == boolean_false_node)

diff --git a/gcc/analyzer/region-model.cc b/gcc/analyzer/region-model.cc
index 2cfded836b6dff61f4d8a4e4bbef67929dacae3c..c837ec6ed3b8858fd1869bea98d3b7a40a88d837 100644 (file)
--- a/gcc/analyzer/region-model.cc
+++ b/gcc/analyzer/region-model.cc
@@ -670,7 +670,7 @@ constant_svalue::eval_condition (constant_svalue *lhs,
   if (types_compatible_p (TREE_TYPE (lhs_const), TREE_TYPE (rhs_const)))
     {
       tree comparison
-       = fold_build2 (op, boolean_type_node, lhs_const, rhs_const);
+       = fold_binary (op, boolean_type_node, lhs_const, rhs_const);
       if (comparison == boolean_true_node)
        return tristate (tristate::TS_TRUE);
       if (comparison == boolean_false_node)
@@ -4088,9 +4088,9 @@ region_model::on_assignment (const gassign *assign, region_model_context *ctxt)
        if (tree rhs1_cst = maybe_get_constant (rhs1_sid))
          if (tree rhs2_cst = maybe_get_constant (rhs2_sid))
            {
-             tree result = fold_build2 (op, TREE_TYPE (lhs),
+             tree result = fold_binary (op, TREE_TYPE (lhs),
                                         rhs1_cst, rhs2_cst);
-             if (CONSTANT_CLASS_P (result))
+             if (result && CONSTANT_CLASS_P (result))
                {
                  svalue_id result_sid
                    = get_or_create_constant_svalue (result);