Hi,
This is an updated version of
https://gcc.gnu.org/ml/gcc-patches/2015-07/msg02196.html.
Patch to fix PR66726 missed optimization, factor conversion out of
COND_EXPR caused a regression for targets with branch cost greater than
i.e., testcase gcc.dg/pr46309.c failed for these targets. I posted a
patch for this which had some issues. Please find an updated version of
this patch that now passes regression.
This patch makes optimize_range_tests understand the factored out
COND_EXPR. i.e., Updated the final_range_test_p to look for the new
pattern. Changed the maybe_optimize_range_tests (which does the inter
basic block range test optimization) accordingly.
Bootstrapped and regression tested on x86_64-none-linux-gnu with no new
regressions. And also regression tested on arm-none-linux-gnu and
aarch64-none-linux-gnu with no new regressions.
Is this Ok for trunk?
Thanks,
Kugan
gcc/ChangeLog:
2016-01-19 Kugan Vivekanandarajah <kug...@linaro.org>
PR middle-end/66726
* tree-ssa-reassoc.c (optimize_range_tests): Handle tcc_compare stmt
whose result is used in PHI.
(maybe_optimize_range_tests): Likewise.
(final_range_test_p): Lokweise.
diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c
index e53cc56..d0a5cee 100644
--- a/gcc/tree-ssa-reassoc.c
+++ b/gcc/tree-ssa-reassoc.c
@@ -2687,18 +2687,33 @@ optimize_range_tests (enum tree_code opcode,
# _345 = PHI <_123(N), 1(...), 1(...)>
where _234 has bool type, _123 has single use and
bb N has a single successor M. This is commonly used in
+ the last block of a range test.
+
+ Also Return true if STMT is tcc_compare like:
+ <bb N>:
+ ...
+ _234 = a_2(D) == 2;
+
+ <bb M>:
+ # _345 = PHI <_234(N), 1(...), 1(...)>
+ _346 = (int) _345;
+ where _234 has booltype, single use and
+ bb N has a single successor M. This is commonly used in
the last block of a range test. */
static bool
final_range_test_p (gimple *stmt)
{
- basic_block bb, rhs_bb;
+ basic_block bb, rhs_bb, lhs_bb;
edge e;
tree lhs, rhs;
use_operand_p use_p;
gimple *use_stmt;
- if (!gimple_assign_cast_p (stmt))
+ if (!gimple_assign_cast_p (stmt)
+ && (!is_gimple_assign (stmt)
+ || (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt))
+ != tcc_comparison)))
return false;
bb = gimple_bb (stmt);
if (!single_succ_p (bb))
@@ -2709,11 +2724,16 @@ final_range_test_p (gimple *stmt)
lhs = gimple_assign_lhs (stmt);
rhs = gimple_assign_rhs1 (stmt);
- if (!INTEGRAL_TYPE_P (TREE_TYPE (lhs))
- || TREE_CODE (rhs) != SSA_NAME
- || TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE)
+ if (gimple_assign_cast_p (stmt)
+ && (!INTEGRAL_TYPE_P (TREE_TYPE (lhs))
+ || TREE_CODE (rhs) != SSA_NAME
+ || TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE))
return false;
+ if (!gimple_assign_cast_p (stmt)
+ && (TREE_CODE (TREE_TYPE (lhs)) != BOOLEAN_TYPE))
+ return false;
+
/* Test whether lhs is consumed only by a PHI in the only successor bb. */
if (!single_imm_use (lhs, &use_p, &use_stmt))
return false;
@@ -2723,10 +2743,20 @@ final_range_test_p (gimple *stmt)
return false;
/* And that the rhs is defined in the same loop. */
- rhs_bb = gimple_bb (SSA_NAME_DEF_STMT (rhs));
- if (rhs_bb == NULL
- || !flow_bb_inside_loop_p (loop_containing_stmt (stmt), rhs_bb))
- return false;
+ if (gimple_assign_cast_p (stmt))
+ {
+ if (TREE_CODE (rhs) != SSA_NAME
+ || !(rhs_bb = gimple_bb (SSA_NAME_DEF_STMT (rhs)))
+ || !flow_bb_inside_loop_p (loop_containing_stmt (stmt), rhs_bb))
+ return false;
+ }
+ else
+ {
+ if (TREE_CODE (lhs) != SSA_NAME
+ || !(lhs_bb = gimple_bb (SSA_NAME_DEF_STMT (lhs)))
+ || !flow_bb_inside_loop_p (loop_containing_stmt (stmt), lhs_bb))
+ return false;
+ }
return true;
}
@@ -3119,6 +3149,8 @@ maybe_optimize_range_tests (gimple *stmt)
/* stmt is
_123 = (int) _234;
+ OR
+ _234 = a_2(D) == 2;
followed by:
<bb M>:
@@ -3148,6 +3180,8 @@ maybe_optimize_range_tests (gimple *stmt)
of the bitwise or resp. and, recursively. */
if (!get_ops (rhs, code, &ops,
loop_containing_stmt (stmt))
+ && (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt))
+ != tcc_comparison)
&& has_single_use (rhs))
{
/* Otherwise, push the _234 range test itself. */
@@ -3160,6 +3194,23 @@ maybe_optimize_range_tests (gimple *stmt)
ops.safe_push (oe);
bb_ent.last_idx++;
}
+ else if (!get_ops (lhs, code, &ops,
+ loop_containing_stmt (stmt))
+ && TREE_CODE (lhs) == SSA_NAME
+ && INTEGRAL_TYPE_P (TREE_TYPE (lhs))
+ && is_gimple_assign (stmt)
+ && (TREE_CODE_CLASS (gimple_assign_rhs_code (stmt))
+ == tcc_comparison)
+ && has_single_use (lhs))
+ {
+ operand_entry *oe = operand_entry_pool.allocate ();
+ oe->op = lhs;
+ oe->rank = code;
+ oe->id = 0;
+ oe->count = 1;
+ ops.safe_push (oe);
+ bb_ent.last_idx++;
+ }
else
bb_ent.last_idx = ops.length ();
bb_ent.op = rhs;
@@ -3243,26 +3294,60 @@ maybe_optimize_range_tests (gimple *stmt)
{
imm_use_iterator iter;
use_operand_p use_p;
- gimple *use_stmt, *cast_stmt = NULL;
+ gimple *use_stmt, *cast_or_tcc_cmp_stmt = NULL;
FOR_EACH_IMM_USE_STMT (use_stmt, iter, bbinfo[idx].op)
- if (is_gimple_debug (use_stmt))
+ if (is_gimple_debug (use_stmt)
+ || (TREE_CODE (new_op) == SSA_NAME
+ && !reassoc_stmt_dominates_stmt_p
+ (SSA_NAME_DEF_STMT (new_op), use_stmt)))
continue;
- else if (gimple_code (use_stmt) == GIMPLE_COND
- || gimple_code (use_stmt) == GIMPLE_PHI)
- FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
- SET_USE (use_p, new_op);
+ else if (gimple_code (use_stmt) == GIMPLE_PHI)
+ FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+ SET_USE (use_p, new_op);
+ else if (gimple_code (use_stmt) == GIMPLE_COND)
+ {
+ tree new_type, new_lhs;
+ gassign *g;
+ gcond *cond_stmt = as_a <gcond *> (use_stmt);
+ new_type = TREE_TYPE (gimple_cond_lhs (cond_stmt));
+ if (!types_compatible_p (new_type, TREE_TYPE (new_op)))
+ {
+ new_lhs = make_ssa_name (new_type);
+ if (is_gimple_min_invariant (new_op))
+ {
+ new_op = fold_convert (new_type, new_op);
+ g = gimple_build_assign (new_lhs, new_op);
+ }
+ else
+ g = gimple_build_assign (new_lhs,
+ CONVERT_EXPR, new_op);
+ gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
+ gimple_set_uid (g, gimple_uid (use_stmt));
+ gimple_set_visited (g, true);
+ gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+ }
+ else
+ new_lhs = new_op;
+ FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
+ SET_USE (use_p, new_lhs);
+ }
+ else if ((is_gimple_assign (use_stmt)
+ && (TREE_CODE_CLASS (gimple_assign_rhs_code
(use_stmt)) == tcc_comparison)))
+ {
+ cast_or_tcc_cmp_stmt = use_stmt;
+ }
else if (gimple_assign_cast_p (use_stmt))
- cast_stmt = use_stmt;
- else
- gcc_unreachable ();
- if (cast_stmt)
+ cast_or_tcc_cmp_stmt = use_stmt;
+
+ if (cast_or_tcc_cmp_stmt)
{
gcc_assert (bb == last_bb);
- tree lhs = gimple_assign_lhs (cast_stmt);
+ tree lhs = gimple_assign_lhs (cast_or_tcc_cmp_stmt);
tree new_lhs = make_ssa_name (TREE_TYPE (lhs));
enum tree_code rhs_code
- = gimple_assign_rhs_code (cast_stmt);
+ = gimple_assign_cast_p (cast_or_tcc_cmp_stmt) ?
+ gimple_assign_rhs_code (cast_or_tcc_cmp_stmt) :
CONVERT_EXPR;
gassign *g;
if (is_gimple_min_invariant (new_op))
{
@@ -3271,13 +3356,14 @@ maybe_optimize_range_tests (gimple *stmt)
}
else
g = gimple_build_assign (new_lhs, rhs_code, new_op);
- gimple_stmt_iterator gsi = gsi_for_stmt (cast_stmt);
- gimple_set_uid (g, gimple_uid (cast_stmt));
+ gimple_stmt_iterator gsi = gsi_for_stmt
(cast_or_tcc_cmp_stmt);
+ gimple_set_uid (g, gimple_uid (cast_or_tcc_cmp_stmt));
gimple_set_visited (g, true);
- gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+ gsi_insert_after (&gsi, g, GSI_SAME_STMT);
FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
if (is_gimple_debug (use_stmt))
continue;
+ else if (is_gimple_assign (use_stmt));
else if (gimple_code (use_stmt) == GIMPLE_COND
|| gimple_code (use_stmt) == GIMPLE_PHI)
FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
