On 8/6/19 5:44 PM, Marc Glisse wrote:
> On Tue, 6 Aug 2019, Martin Liška wrote:
>
>> Anyway, I'm sending patch that considers only such new/delete operators
>> that are not a clone of an original type. That should make the current
>> DCE code more solid.
>
> DECL_IS_REPLACEABLE_OPERATOR_NEW_P seems to have been replaced with
> DECL_IS_OPERATOR_NEW_P. Is that on purpose?
Whoops, that was not intentional, thanks for heads up.
>
> I like your cleanup of having a single function to decide if this is the kind
> of operator new/delete DCE can handle, but you may have introduced long lines
> in the substitution.
>
Long lines should be fixed now as well.
Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
Ready to be installed?
Thanks,
Martin
>From 6ccff415a8931558cf7f1a01b34daec999e9f5af Mon Sep 17 00:00:00 2001
From: Martin Liska <mli...@suse.cz>
Date: Tue, 6 Aug 2019 16:14:48 +0200
Subject: [PATCH] Detect not-cloned new/delete operators in DCE.
gcc/ChangeLog:
2019-08-06 Martin Liska <mli...@suse.cz>
* gimple.c (gimple_call_operator_delete_p): Remove.
* gimple.h (gimple_call_operator_delete_p): Likewise.
* tree-ssa-dce.c (operator_new_candidate_p): New.
(operator_delete_candidate_p): Likewise.
(mark_stmt_if_obviously_necessary): Use operator_new_candidate_p
and operator_delete_candidate_p in order to detect operators
that are not not clones.
(mark_all_reaching_defs_necessary_1): Likewise.
(propagate_necessity): Likewise.
(eliminate_unnecessary_stmts): Likewise.
---
gcc/gimple.c | 12 ---------
gcc/gimple.h | 1 -
gcc/tree-ssa-dce.c | 63 ++++++++++++++++++++++++++++------------------
3 files changed, 38 insertions(+), 38 deletions(-)
diff --git a/gcc/gimple.c b/gcc/gimple.c
index 633ef512a19..684b8831b4d 100644
--- a/gcc/gimple.c
+++ b/gcc/gimple.c
@@ -2707,18 +2707,6 @@ gimple_builtin_call_types_compatible_p (const gimple *stmt, tree fndecl)
return true;
}
-/* Return true when STMT is operator delete call. */
-
-bool
-gimple_call_operator_delete_p (const gcall *stmt)
-{
- tree fndecl;
-
- if ((fndecl = gimple_call_fndecl (stmt)) != NULL_TREE)
- return DECL_IS_OPERATOR_DELETE_P (fndecl);
- return false;
-}
-
/* Return true when STMT is builtins call. */
bool
diff --git a/gcc/gimple.h b/gcc/gimple.h
index 55f5d0d33d9..7a1e1f49099 100644
--- a/gcc/gimple.h
+++ b/gcc/gimple.h
@@ -1548,7 +1548,6 @@ extern alias_set_type gimple_get_alias_set (tree);
extern bool gimple_ior_addresses_taken (bitmap, gimple *);
extern bool gimple_builtin_call_types_compatible_p (const gimple *, tree);
extern combined_fn gimple_call_combined_fn (const gimple *);
-extern bool gimple_call_operator_delete_p (const gcall *);
extern bool gimple_call_builtin_p (const gimple *);
extern bool gimple_call_builtin_p (const gimple *, enum built_in_class);
extern bool gimple_call_builtin_p (const gimple *, enum built_in_function);
diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c
index afb7bd9dedc..66eb085b65f 100644
--- a/gcc/tree-ssa-dce.c
+++ b/gcc/tree-ssa-dce.c
@@ -114,6 +114,25 @@ static bool cfg_altered;
/* When non-NULL holds map from basic block index into the postorder. */
static int *bb_postorder;
+/* Return true when FNDECL is a new operator and not a clone. */
+
+static bool
+operator_new_candidate_p (tree fndecl)
+{
+ return (fndecl != NULL_TREE
+ && DECL_IS_REPLACEABLE_OPERATOR_NEW_P (fndecl)
+ && DECL_ABSTRACT_ORIGIN (fndecl) == NULL_TREE);
+}
+
+/* Return true when FNDECL is a delete operator and not a clone. */
+
+static bool
+operator_delete_candidate_p (tree fndecl)
+{
+ return (fndecl != NULL_TREE
+ && DECL_IS_OPERATOR_DELETE_P (fndecl)
+ && DECL_ABSTRACT_ORIGIN (fndecl) == NULL_TREE);
+}
/* True if we should treat any stmt with a vdef as necessary. */
@@ -248,7 +267,7 @@ mark_stmt_if_obviously_necessary (gimple *stmt, bool aggressive)
if (callee != NULL_TREE
&& flag_allocation_dce
- && DECL_IS_REPLACEABLE_OPERATOR_NEW_P (callee))
+ && operator_new_candidate_p (callee))
return;
/* Most, but not all function calls are required. Function calls that
@@ -613,8 +632,8 @@ mark_all_reaching_defs_necessary_1 (ao_ref *ref ATTRIBUTE_UNUSED,
}
if (callee != NULL_TREE
- && (DECL_IS_REPLACEABLE_OPERATOR_NEW_P (callee)
- || DECL_IS_OPERATOR_DELETE_P (callee)))
+ && (operator_new_candidate_p (callee)
+ || operator_delete_candidate_p (callee)))
return false;
}
@@ -800,21 +819,18 @@ propagate_necessity (bool aggressive)
which feed this statement's uses as necessary. */
ssa_op_iter iter;
tree use;
+ tree fndecl;
/* If this is a call to free which is directly fed by an
allocation function do not mark that necessary through
processing the argument. */
bool is_delete_operator
= (is_gimple_call (stmt)
- && gimple_call_operator_delete_p (as_a <gcall *> (stmt)));
+ && (fndecl = gimple_call_fndecl (as_a <gcall *> (stmt)))
+ && operator_delete_candidate_p (fndecl));
if (is_delete_operator
|| gimple_call_builtin_p (stmt, BUILT_IN_FREE))
{
- /* It can happen that a user delete operator has the pointer
- argument optimized out already. */
- if (gimple_call_num_args (stmt) == 0)
- continue;
-
tree ptr = gimple_call_arg (stmt, 0);
gimple *def_stmt;
tree def_callee;
@@ -827,7 +843,7 @@ propagate_necessity (bool aggressive)
&& (DECL_FUNCTION_CODE (def_callee) == BUILT_IN_ALIGNED_ALLOC
|| DECL_FUNCTION_CODE (def_callee) == BUILT_IN_MALLOC
|| DECL_FUNCTION_CODE (def_callee) == BUILT_IN_CALLOC))
- || DECL_IS_REPLACEABLE_OPERATOR_NEW_P (def_callee)))
+ || operator_new_candidate_p (def_callee)))
{
/* Delete operators can have alignment and (or) size as next
arguments. When being a SSA_NAME, they must be marked
@@ -900,8 +916,8 @@ propagate_necessity (bool aggressive)
continue;
if (callee != NULL_TREE
- && (DECL_IS_REPLACEABLE_OPERATOR_NEW_P (callee)
- || DECL_IS_OPERATOR_DELETE_P (callee)))
+ && (operator_new_candidate_p (callee)
+ || operator_delete_candidate_p (callee)))
continue;
/* Calls implicitly load from memory, their arguments
@@ -1313,6 +1329,7 @@ eliminate_unnecessary_stmts (void)
auto_bitmap debug_seen;
for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi); gsi = psi)
{
+ tree fndecl;
stmt = gsi_stmt (gsi);
psi = gsi;
@@ -1326,20 +1343,16 @@ eliminate_unnecessary_stmts (void)
if (gimple_plf (stmt, STMT_NECESSARY)
&& (gimple_call_builtin_p (stmt, BUILT_IN_FREE)
|| (is_gimple_call (stmt)
- && gimple_call_operator_delete_p (as_a <gcall *> (stmt)))))
+ && (fndecl = gimple_call_fndecl (as_a <gcall *> (stmt)))
+ && operator_delete_candidate_p (fndecl))))
{
- /* It can happen that a user delete operator has the pointer
- argument optimized out already. */
- if (gimple_call_num_args (stmt) > 0)
+ tree ptr = gimple_call_arg (stmt, 0);
+ if (TREE_CODE (ptr) == SSA_NAME)
{
- tree ptr = gimple_call_arg (stmt, 0);
- if (TREE_CODE (ptr) == SSA_NAME)
- {
- gimple *def_stmt = SSA_NAME_DEF_STMT (ptr);
- if (!gimple_nop_p (def_stmt)
- && !gimple_plf (def_stmt, STMT_NECESSARY))
- gimple_set_plf (stmt, STMT_NECESSARY, false);
- }
+ gimple *def_stmt = SSA_NAME_DEF_STMT (ptr);
+ if (!gimple_nop_p (def_stmt)
+ && !gimple_plf (def_stmt, STMT_NECESSARY))
+ gimple_set_plf (stmt, STMT_NECESSARY, false);
}
}
@@ -1394,7 +1407,7 @@ eliminate_unnecessary_stmts (void)
&& DECL_FUNCTION_CODE (call) != BUILT_IN_CALLOC
&& !ALLOCA_FUNCTION_CODE_P
(DECL_FUNCTION_CODE (call))))
- && !DECL_IS_REPLACEABLE_OPERATOR_NEW_P (call))))
+ && !operator_new_candidate_p (call))))
{
something_changed = true;
if (dump_file && (dump_flags & TDF_DETAILS))
--
2.22.0
