tree if conversion is an enabler pass for vectorization, so by
default, it is only turned on when vectorization is on, but may also
depend on the optimization level. Currently, the logic to handle this
is in the gate function which become hard to understand and extend.
The proposed patch move the logic from the gate function to
'finish_option' which is much clearer. The downside of this patch is
that function specific optimization node needs to be created for some
cases during omp-lowering.
Comments?
thanks,
David
Index: opts.c
===================================================================
--- opts.c (revision 202229)
+++ opts.c (working copy)
@@ -824,6 +824,12 @@ finish_options (struct gcc_options *opts
}
}
+ if (!opts_set->x_flag_tree_loop_if_convert)
+ opts->x_flag_tree_loop_if_convert = opts->x_flag_tree_vectorize;
+
+ if (!opts_set->x_flag_tree_loop_if_convert_stores)
+ opts->x_flag_tree_loop_if_convert_stores = opts->x_flag_tree_vectorize;
+
/* Set PARAM_MAX_STORES_TO_SINK to 0 if either vectorization or if-conversion
is disabled. */
if (!opts->x_flag_tree_vectorize || !opts->x_flag_tree_loop_if_convert)
Index: omp-low.c
===================================================================
--- omp-low.c (revision 202229)
+++ omp-low.c (working copy)
@@ -5690,8 +5690,36 @@ expand_omp_simd (struct omp_region *regi
|| !global_options_set.x_flag_tree_vectorize)
&& loop->safelen > 1)
{
+ bool need_to_turn_on_if_cvt = false;
+ bool need_to_turn_on_if_cvt_stores = false;
+
loop->force_vect = true;
cfun->has_force_vect_loops = true;
+
+ /* Now check if it is needed to turn on tree-if-convert. */
+
+ if (!global_options_set.x_flag_tree_loop_if_convert
+ && !flag_tree_loop_if_convert)
+ need_to_turn_on_if_cvt = true;
+
+ if (!global_options_set.x_flag_tree_loop_if_convert_stores
+ && !flag_tree_loop_if_convert_stores)
+ need_to_turn_on_if_cvt_stores = true;
+
+ if (need_to_turn_on_if_cvt || need_to_turn_on_if_cvt_stores)
+ {
+ if (need_to_turn_on_if_cvt)
+ global_options.x_flag_tree_loop_if_convert = 1;
+ if (need_to_turn_on_if_cvt_stores)
+ global_options.x_flag_tree_loop_if_convert_stores = 1;
+ DECL_FUNCTION_SPECIFIC_OPTIMIZATION (current_function_decl)
+ = build_optimization_node ();
+ /* restore */
+ if (need_to_turn_on_if_cvt)
+ global_options.x_flag_tree_loop_if_convert = 0;
+ if (need_to_turn_on_if_cvt_stores)
+ global_options.x_flag_tree_loop_if_convert_stores = 0;
+ }
}
}
}
Index: ChangeLog
===================================================================
--- ChangeLog (revision 202229)
+++ ChangeLog (working copy)
@@ -1,3 +1,12 @@
+2013-09-13 Xinliang David Li <davi...@google.com>
+
+ * omp-low.c (expand_omp_simd): Build optimization cl
+ node if necessary.
+ * opts.c (finish_option): Enable/Disable tree if-cvt
+ if not explicitly set.
+ * tree-if-conv.c (gate_tree_if_conversion): Simplify.
+
+
2013-08-29 Xinliang David Li <davi...@google.com>
* tree-vect-slp.c (destroy_bb_vec_info): Data ref cleanup.
Index: common.opt
===================================================================
--- common.opt (revision 202229)
+++ common.opt (working copy)
@@ -1308,7 +1308,7 @@ EnumValue
Enum(stack_reuse_level) String(none) Value(SR_NONE)
ftree-loop-if-convert
-Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
+Common Report Var(flag_tree_loop_if_convert) Optimization
Convert conditional jumps in innermost loops to branchless equivalents
ftree-loop-if-convert-stores
Index: tree-if-conv.c
===================================================================
--- tree-if-conv.c (revision 202229)
+++ tree-if-conv.c (working copy)
@@ -1815,10 +1815,8 @@ main_tree_if_conversion (void)
static bool
gate_tree_if_conversion (void)
{
- return (((flag_tree_vectorize || cfun->has_force_vect_loops)
- && flag_tree_loop_if_convert != 0)
- || flag_tree_loop_if_convert == 1
- || flag_tree_loop_if_convert_stores == 1);
+ return (flag_tree_loop_if_convert
+ || flag_tree_loop_if_convert_stores);
}
namespace {
