resend the patch for stage1:
https://gcc.gnu.org/pipermail/gcc-patches/2020-January/538186.html
The performance of exchange2 built with PGO will decrease ~28% by r278808
due to profile count set incorrectly. The cloned nodes are updated to a
very small count caused later pass cunroll fail to unroll the recursive
function in exchange2.
digits_2 ->
digits_2.constprop.0, digits_2.constprop.1, etc.
1. Enable proportion orig_sum to the new nodes for self recursive node
(k means multiple self recursive calls):
new_sum = (orig_sum + new_sum) * 1 / k \
* self_recursive_probability * (1 / param_ipa_cp_max_recursive_depth).
2. Two mutually recursive functions are not supported in self recursive
clone yet so also not supported in update_profiling_info here.
3. Improve value range for param_ipa_cp_max_recursive_depth to (0, 8).
If it calls itself two different sets, usually recursive boudary limit
will stop the specialize first, otherwise it is slow even without
recursive specialize.
gcc/ChangeLog:
2020-05-29 Xionghu Luo <luo...@linux.ibm.com>
* ipa-cp.c (update_profiling_info): Check self_scc node.
* params.opt (ipa-cp-max-recursive-depth): Set param range.
gcc/testsuite/ChangeLog:
2020-05-29 Xionghu Luo <luo...@linux.ibm.com>
* gcc.dg/ipa/ipa-clone-3.c: Update count.
---
gcc/ipa-cp.c | 33 +++++++++++++++++++++++++-
gcc/params.opt | 2 +-
gcc/testsuite/gcc.dg/ipa/ipa-clone-3.c | 2 +-
3 files changed, 34 insertions(+), 3 deletions(-)
diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index c64e9104a94..919c741ecfa 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -2046,7 +2046,7 @@ propagate_vals_across_arith_jfunc (cgraph_edge *cs,
/* Recursively generate lattice values with a limited count. */
FOR_EACH_VEC_ELT (val_seeds, i, src_val)
{
- for (int j = 1; j < max_recursive_depth; j++)
+ for (int j = 0; j < max_recursive_depth; j++)
{
tree cstval = get_val_across_arith_op (opcode, opnd1_type, opnd2,
src_val, res_type);
@@ -4345,6 +4345,37 @@ update_profiling_info (struct cgraph_node *orig_node,
false);
new_sum = stats.count_sum;
+ class ipa_node_params *info = IPA_NODE_REF (orig_node);
+ if (info && info->node_is_self_scc)
+ {
+ profile_count self_recursive_count = profile_count::zero ();
+ unsigned k = 0;
+
+ /* The self recursive edge is on the orig_node. */
+ for (cs = orig_node->callees; cs; cs = cs->next_callee)
+ if (ipa_edge_within_scc (cs))
+ {
+ cgraph_node *callee = cs->callee->function_symbol ();
+ if (callee && cs->caller == cs->callee)
+ {
+ self_recursive_count += cs->count;
+ k++;
+ }
+ }
+
+ /* Proportion count for multiple self recursive node. */
+ if (k)
+ self_recursive_count.apply_scale (1, k);
+
+ /* Proportion count for self recursive node from all callers. */
+ new_sum
+ = (orig_sum + new_sum).apply_scale (self_recursive_count, orig_sum);
+
+ /* Proportion count for specialized cloned node. */
+ if (param_ipa_cp_max_recursive_depth)
+ new_sum = new_sum.apply_scale (1, param_ipa_cp_max_recursive_depth);
+ }
+
if (orig_node_count < orig_sum + new_sum)
{
if (dump_file)
diff --git a/gcc/params.opt b/gcc/params.opt
index 4aec480798b..ad000145dfb 100644
--- a/gcc/params.opt
+++ b/gcc/params.opt
@@ -199,7 +199,7 @@ Common Joined UInteger Var(param_ipa_cp_loop_hint_bonus)
Init(64) Param Optimiza
Compile-time bonus IPA-CP assigns to candidates which make loop bounds or
strides known.
-param=ipa-cp-max-recursive-depth=
-Common Joined UInteger Var(param_ipa_cp_max_recursive_depth) Init(8) Param
Optimization
+Common Joined UInteger Var(param_ipa_cp_max_recursive_depth) Init(7)
IntegerRange(0, 8) Param Optimization
Maximum depth of recursive cloning for self-recursive function.
-param=ipa-cp-min-recursive-probability=
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-clone-3.c
b/gcc/testsuite/gcc.dg/ipa/ipa-clone-3.c
index a73cb8b63fc..1efa23ae109 100644
--- a/gcc/testsuite/gcc.dg/ipa/ipa-clone-3.c
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-clone-3.c
@@ -41,4 +41,4 @@ int main ()
return recur_fn (&v);
}
-/* { dg-final { scan-ipa-dump-times "Creating a specialized node of
recur_fn/\[0-9\]*\\." 8 "cp" } } */
+/* { dg-final { scan-ipa-dump-times "Creating a specialized node of
recur_fn/\[0-9\]*\\." 9 "cp" } } */
--
2.21.0.777.g83232e3864
