Hi,
Attached patch Register ranges for y in (x COND y) for Early VRP.
Bootstrapped and regression tested on x86_64-linux-gnu with no new
regressions. Is this OK for trunk?
Thanks,
Kugan
gcc/ChangeLog:
2016-10-06 Kugan Vivekanandarajah <kug...@linaro.org>
* tree-vrp.c (evrp_dom_walker::try_add_new_range): New.
(evrp_dom_walker::before_dom_children): Infer and push new value
ranges for x in y COND x.
>From a90aac71afe66d47268dfb3d0cb7657c96e96b15 Mon Sep 17 00:00:00 2001
From: Kugan Vivekanandarajah <kugan.vivekanandara...@linaro.org>
Date: Mon, 3 Oct 2016 10:12:27 +1100
Subject: [PATCH 2/5] Register ranges for y in x < y
1
---
gcc/tree-vrp.c | 54 ++++++++++++++++++++++++++++++++++++++++--------------
1 file changed, 40 insertions(+), 14 deletions(-)
diff --git a/gcc/tree-vrp.c b/gcc/tree-vrp.c
index 46bbd82..0892709 100644
--- a/gcc/tree-vrp.c
+++ b/gcc/tree-vrp.c
@@ -10640,6 +10640,7 @@ public:
virtual void after_dom_children (basic_block);
void push_value_range (const_tree var, value_range *vr);
value_range *pop_value_range (const_tree var);
+ void try_add_new_range (tree op, tree_code code, tree limit);
/* Cond_stack holds the old VR. */
auto_vec<std::pair <const_tree, value_range*> > stack;
@@ -10647,20 +10648,42 @@ public:
vec<gimple *> stmts_to_fixup;
};
+
+/* Add new range to OP such that (OP CODE LIMIT) is true. */
+
+void
+evrp_dom_walker::try_add_new_range (tree op, tree_code code, tree limit)
+{
+ value_range vr = VR_INITIALIZER;
+ value_range *old_vr = get_value_range (op);
+
+ /* Discover VR when condition is true. */
+ extract_range_for_var_from_comparison_expr (op, code, op,
+ limit, &vr);
+ if (old_vr->type == VR_RANGE || old_vr->type == VR_ANTI_RANGE)
+ vrp_intersect_ranges (&vr, old_vr);
+ /* If we found any usable VR, set the VR to ssa_name and create a
+ PUSH old value in the stack with the old VR. */
+ if (vr.type == VR_RANGE || vr.type == VR_ANTI_RANGE)
+ {
+ value_range *new_vr = vrp_value_range_pool.allocate ();
+ *new_vr = vr;
+ push_value_range (op, new_vr);
+ }
+}
+
/* See if there is any new scope is entered with new VR and set that VR to
ssa_name before visiting the statements in the scope. */
edge
evrp_dom_walker::before_dom_children (basic_block bb)
{
- value_range *new_vr = NULL;
tree op0 = NULL_TREE;
push_value_range (NULL_TREE, NULL);
if (single_pred_p (bb))
{
edge e = single_pred_edge (bb);
- value_range vr = VR_INITIALIZER;
gimple *stmt = last_stmt (e->src);
if (stmt
&& gimple_code (stmt) == GIMPLE_COND
@@ -10673,7 +10696,6 @@ evrp_dom_walker::before_dom_children (basic_block bb)
here. */
tree op1 = gimple_cond_rhs (stmt);
tree_code code = gimple_cond_code (stmt);
- value_range *old_vr = get_value_range (op0);
if (TREE_OVERFLOW_P (op1))
op1 = drop_tree_overflow (op1);
@@ -10682,18 +10704,22 @@ evrp_dom_walker::before_dom_children (basic_block bb)
if (e->flags & EDGE_FALSE_VALUE)
code = invert_tree_comparison (gimple_cond_code (stmt),
HONOR_NANS (op0));
- /* Discover VR when condition is true. */
- extract_range_for_var_from_comparison_expr (op0, code, op0, op1, &vr);
- if (old_vr->type == VR_RANGE || old_vr->type == VR_ANTI_RANGE)
- vrp_intersect_ranges (&vr, old_vr);
-
- /* If we found any usable VR, set the VR to ssa_name and create a
- PUSH old value in the stack with the old VR. */
- if (vr.type == VR_RANGE || vr.type == VR_ANTI_RANGE)
+ /* Add VR when (OP0 CODE OP1) condition is true. */
+ try_add_new_range (op0, code, op1);
+
+
+ /* Register ranges for y in x < y where
+ y might have ranges that are useful. */
+ tree limit;
+ tree_code new_code;
+ if (TREE_CODE (op1) == SSA_NAME
+ && extract_code_and_val_from_cond_with_ops (op1, code,
+ op0, op1,
+ false,
+ &new_code, &limit))
{
- new_vr = vrp_value_range_pool.allocate ();
- *new_vr = vr;
- push_value_range (op0, new_vr);
+ /* Add VR when (OP1 NEW_CODE LIMIT) condition is true. */
+ try_add_new_range (op1, new_code, limit);
}
}
}
--
2.7.4
