From: Ju-Zhe Zhong <juzhe.zh...@rivai.ai>
Hi, Richi.
This patch is adding LEN_MASK_STORE into DSE.
My understanding is LEN_MASK_STORE is predicated by mask and len.
No matter len is constant or not, the ao_ref should be the same as MASK_STORE.
Wheras for LEN_STORE, when len is constant, we use (len - bias), otherwise, it's
the same as MASK_STORE/LEN_MASK_STORE.
Not sure whether I am on the same page with you, feel free to correct me.
Thanks.
gcc/ChangeLog:
* tree-ssa-dse.cc (initialize_ao_ref_for_dse): Add LEN_MASK_STORE and
fix LEN_STORE.
(dse_optimize_stmt): Add LEN_MASK_STORE.
---
gcc/tree-ssa-dse.cc | 47 ++++++++++++++++++++++++++++++---------------
1 file changed, 31 insertions(+), 16 deletions(-)
diff --git a/gcc/tree-ssa-dse.cc b/gcc/tree-ssa-dse.cc
index 3c7a2e9992d..f8338037a61 100644
--- a/gcc/tree-ssa-dse.cc
+++ b/gcc/tree-ssa-dse.cc
@@ -48,6 +48,7 @@ along with GCC; see the file COPYING3. If not see
#include "tree-ssa-loop-niter.h"
#include "cfgloop.h"
#include "tree-data-ref.h"
+#include "internal-fn.h"
/* This file implements dead store elimination.
@@ -157,23 +158,36 @@ initialize_ao_ref_for_dse (gimple *stmt, ao_ref *write,
bool may_def_ok = false)
switch (gimple_call_internal_fn (stmt))
{
case IFN_LEN_STORE:
- ao_ref_init_from_ptr_and_size
- (write, gimple_call_arg (stmt, 0),
- int_const_binop (MINUS_EXPR,
- gimple_call_arg (stmt, 2),
- gimple_call_arg (stmt, 4)));
- return true;
case IFN_MASK_STORE:
- /* We cannot initialize a must-def ao_ref (in all cases) but we
- can provide a may-def variant. */
- if (may_def_ok)
- {
- ao_ref_init_from_ptr_and_size
- (write, gimple_call_arg (stmt, 0),
- TYPE_SIZE_UNIT (TREE_TYPE (gimple_call_arg (stmt, 3))));
- return true;
- }
- break;
+ case IFN_LEN_MASK_STORE:
+ {
+ int stored_value_index
+ = internal_fn_stored_value_index (gimple_call_internal_fn (stmt));
+ if (gimple_call_internal_fn (stmt) == IFN_LEN_STORE)
+ {
+ tree len = gimple_call_arg (stmt, 2);
+ tree bias = gimple_call_arg (stmt, 4);
+ if (tree_fits_uhwi_p (len))
+ {
+ ao_ref_init_from_ptr_and_size (write,
+ gimple_call_arg (stmt, 0),
+ int_const_binop (MINUS_EXPR,
+ len, bias));
+ return true;
+ }
+ }
+ /* We cannot initialize a must-def ao_ref (in all cases) but we
+ can provide a may-def variant. */
+ if (may_def_ok)
+ {
+ ao_ref_init_from_ptr_and_size (
+ write, gimple_call_arg (stmt, 0),
+ TYPE_SIZE_UNIT (
+ TREE_TYPE (gimple_call_arg (stmt, stored_value_index))));
+ return true;
+ }
+ break;
+ }
default:;
}
}
@@ -1502,6 +1516,7 @@ dse_optimize_stmt (function *fun, gimple_stmt_iterator
*gsi, sbitmap live_bytes)
{
case IFN_LEN_STORE:
case IFN_MASK_STORE:
+ case IFN_LEN_MASK_STORE:
{
enum dse_store_status store_status;
store_status = dse_classify_store (&ref, stmt, false, live_bytes);
--
2.36.3
