Cleanup hadnling of modref access_nodes in tree-ssa-alias and tree-ssa-dse
Commit Message
Hi,
this patch implements the cleanup suggested by Richard to move code
getting tree op from access_node and stmt to a common place. I also commonized
logic to build ao_ref. While I was on it I also replaced FOR_EACH_* by range
for since they reads better.
Bootstrapped/regtesed x86_64-linux, will commit it shortly.
Honza
gcc/ChangeLog:
2021-11-14 Jan Hubicka <hubicka@ucw.cz>
* ipa-modref-tree.c (modref_access_node::get_call_arg): New member
function.
(modref_access_node::get_ao_ref): Likewise.
* ipa-modref-tree.h (modref_access_node::get_call_arg): Declare.
(modref_access_node::get_ao_ref): Declare.
* tree-ssa-alias.c (modref_may_conflict): Use new accessors.
* tree-ssa-dse.c (dse_optimize_call): Use new accessors.
Comments
Hi,
this is variant I comitted. Commonizing the code exposed that I can
drop memory walking when parameter passed is NULL (under assumption of
flag_delete_null_pointer_checks) since it can not point to useful
memory. This was already done in tree-ssa-alias, but not in
tree-ssa-dse. This needed bit of testsuite compensation for cases where
we optimize out invalid memory accesses.
Bootstrapped/regtested x86_64-linux, comitted.
gcc/ChangeLog:
2021-11-14 Jan Hubicka <hubicka@ucw.cz>
* ipa-modref-tree.c (modref_access_node::get_call_arg): New member
function.
(modref_access_node::get_ao_ref): Likewise.
* ipa-modref-tree.h (modref_access_node::get_call_arg): Declare.
(modref_access_node::get_ao_ref): Declare.
* tree-ssa-alias.c (modref_may_conflict): Use new accessors.
* tree-ssa-dse.c (dse_optimize_call): Use new accessors.
gcc/testsuite/ChangeLog:
2021-11-14 Jan Hubicka <hubicka@ucw.cz>
* c-c++-common/asan/null-deref-1.c: Update template.
* c-c++-common/tsan/free_race.c: Update template.
* c-c++-common/tsan/free_race2.c: Update template.
* gcc.dg/ipa/ipa-sra-4.c: Update template.
diff --git a/gcc/ipa-modref-tree.c b/gcc/ipa-modref-tree.c
index 70ec71c3808..6fc2b7298f4 100644
--- a/gcc/ipa-modref-tree.c
+++ b/gcc/ipa-modref-tree.c
@@ -25,6 +25,8 @@ along with GCC; see the file COPYING3. If not see
#include "tree.h"
#include "ipa-modref-tree.h"
#include "selftest.h"
+#include "tree-ssa-alias.h"
+#include "gimple.h"
/* Return true if both accesses are the same. */
bool
@@ -603,6 +605,39 @@ modref_access_node::dump (FILE *out)
fprintf (out, "\n");
}
+/* Return tree corresponding to parameter of the range in STMT. */
+tree
+modref_access_node::get_call_arg (const gcall *stmt) const
+{
+ if (parm_index == MODREF_UNKNOWN_PARM)
+ return NULL;
+ if (parm_index == MODREF_STATIC_CHAIN_PARM)
+ return gimple_call_chain (stmt);
+ /* MODREF_RETSLOT_PARM should not happen in access trees since the store
+ is seen explicitly in the caller. */
+ gcc_checking_assert (parm_index >= 0);
+ if (parm_index >= (int)gimple_call_num_args (stmt))
+ return NULL;
+ return gimple_call_arg (stmt, parm_index);
+}
+
+/* Return tree corresponding to parameter of the range in STMT. */
+bool
+modref_access_node::get_ao_ref (const gcall *stmt, ao_ref *ref) const
+{
+ tree arg;
+
+ if (!parm_offset_known || !(arg = get_call_arg (stmt)))
+ return false;
+ poly_offset_int off = (poly_offset_int)offset
+ + ((poly_offset_int)parm_offset << LOG2_BITS_PER_UNIT);
+ poly_int64 off2;
+ if (!off.to_shwi (&off2))
+ return false;
+ ao_ref_init_from_ptr_and_range (ref, arg, true, off2, size, max_size);
+ return true;
+}
+
#if CHECKING_P
namespace selftest {
diff --git a/gcc/ipa-modref-tree.h b/gcc/ipa-modref-tree.h
index 1fafd59debe..2fcabe480bd 100644
--- a/gcc/ipa-modref-tree.h
+++ b/gcc/ipa-modref-tree.h
@@ -77,7 +77,7 @@ struct GTY(()) modref_access_node
This has to be limited in order to keep dataflow finite. */
unsigned char adjustments;
- /* Return true if access node holds no useful info. */
+ /* Return true if access node holds some useful info. */
bool useful_p () const
{
return parm_index != MODREF_UNKNOWN_PARM;
@@ -88,10 +88,13 @@ struct GTY(()) modref_access_node
bool operator == (modref_access_node &a) const;
/* Return true if range info is useful. */
bool range_info_useful_p () const;
+ /* Return tree corresponding to parameter of the range in STMT. */
+ tree get_call_arg (const gcall *stmt) const;
+ /* Build ao_ref corresponding to the access and return true if succesful. */
+ bool get_ao_ref (const gcall *stmt, class ao_ref *ref) const;
/* Insert A into vector ACCESSES. Limit size of vector to MAX_ACCESSES and
if RECORD_ADJUSTMENT is true keep track of adjustment counts.
- Return 0 if nothing changed, 1 is insertion suceeded and -1 if
- failed. */
+ Return 0 if nothing changed, 1 is insertion suceeded and -1 if failed. */
static int insert (vec <modref_access_node, va_gc> *&accesses,
modref_access_node a, size_t max_accesses,
bool record_adjustments);
diff --git a/gcc/testsuite/c-c++-common/asan/null-deref-1.c b/gcc/testsuite/c-c++-common/asan/null-deref-1.c
index bae016d6419..c967b29b9e2 100644
--- a/gcc/testsuite/c-c++-common/asan/null-deref-1.c
+++ b/gcc/testsuite/c-c++-common/asan/null-deref-1.c
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-fno-omit-frame-pointer -fno-shrink-wrap" } */
+/* { dg-options "-fno-omit-frame-pointer -fno-shrink-wrap -fno-ipa-modref" } */
/* { dg-additional-options "-mno-omit-leaf-frame-pointer" { target { i?86-*-* x86_64-*-* } } } */
/* { dg-shouldfail "asan" } */
diff --git a/gcc/testsuite/c-c++-common/tsan/free_race.c b/gcc/testsuite/c-c++-common/tsan/free_race.c
index 258f7b7420d..831c23e8859 100644
--- a/gcc/testsuite/c-c++-common/tsan/free_race.c
+++ b/gcc/testsuite/c-c++-common/tsan/free_race.c
@@ -1,4 +1,5 @@
/* { dg-shouldfail "tsan" } */
+/* { dg-additional-options "-ldl -fno-ipa-modref" } */
#include <stdlib.h>
diff --git a/gcc/testsuite/c-c++-common/tsan/free_race2.c b/gcc/testsuite/c-c++-common/tsan/free_race2.c
index 3971180c22b..a74d9dc3940 100644
--- a/gcc/testsuite/c-c++-common/tsan/free_race2.c
+++ b/gcc/testsuite/c-c++-common/tsan/free_race2.c
@@ -1,4 +1,5 @@
/* { dg-shouldfail "tsan" } */
+/* { dg-additional-options "-ldl -fno-ipa-modref" } */
#include <stdlib.h>
diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c b/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
index fdbd5e5d72d..c86ae8320a7 100644
--- a/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
+++ b/gcc/testsuite/gcc.dg/ipa/ipa-sra-4.c
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fipa-sra -fno-ipa-pure-const -fdump-ipa-sra" } */
+/* { dg-options "-O2 -fipa-sra -fno-ipa-pure-const -fdump-ipa-sra -fno-ipa-modref" } */
static int
__attribute__((noinline))
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
index 2965902912f..29be1f848b5 100644
--- a/gcc/tree-ssa-alias.c
+++ b/gcc/tree-ssa-alias.c
@@ -2535,13 +2535,10 @@ refs_output_dependent_p (tree store1, tree store2)
IF TBAA_P is true, use TBAA oracle. */
static bool
-modref_may_conflict (const gimple *stmt,
+modref_may_conflict (const gcall *stmt,
modref_tree <alias_set_type> *tt, ao_ref *ref, bool tbaa_p)
{
alias_set_type base_set, ref_set;
- modref_base_node <alias_set_type> *base_node;
- modref_ref_node <alias_set_type> *ref_node;
- size_t i, j, k;
if (tt->every_base)
return true;
@@ -2554,7 +2551,7 @@ modref_may_conflict (const gimple *stmt,
ref_set = ao_ref_alias_set (ref);
int num_tests = 0, max_tests = param_modref_max_tests;
- FOR_EACH_VEC_SAFE_ELT (tt->bases, i, base_node)
+ for (auto base_node : tt->bases)
{
if (tbaa_p && flag_strict_aliasing)
{
@@ -2569,7 +2566,7 @@ modref_may_conflict (const gimple *stmt,
if (base_node->every_ref)
return true;
- FOR_EACH_VEC_SAFE_ELT (base_node->refs, j, ref_node)
+ for (auto ref_node : base_node->refs)
{
/* Do not repeat same test as before. */
if ((ref_set != base_set || base_node->base != ref_node->ref)
@@ -2583,66 +2580,43 @@ modref_may_conflict (const gimple *stmt,
num_tests++;
}
- /* TBAA checks did not disambiguate, try to use base pointer, for
- that we however need to have ref->ref or ref->base. */
- if (ref_node->every_access || (!ref->ref && !ref->base))
+ if (ref_node->every_access)
return true;
- modref_access_node *access_node;
- FOR_EACH_VEC_SAFE_ELT (ref_node->accesses, k, access_node)
+ /* TBAA checks did not disambiguate, try individual accesses. */
+ for (auto access_node : ref_node->accesses)
{
if (num_tests >= max_tests)
return true;
- if (access_node->parm_index == MODREF_UNKNOWN_PARM
- || access_node->parm_index
- >= (int)gimple_call_num_args (stmt))
+ tree arg = access_node.get_call_arg (stmt);
+ if (!arg)
return true;
alias_stats.modref_baseptr_tests++;
- tree arg;
-
- if (access_node->parm_index == MODREF_STATIC_CHAIN_PARM)
- arg = gimple_call_chain (stmt);
- else
- arg = gimple_call_arg (stmt, access_node->parm_index);
if (integer_zerop (arg) && flag_delete_null_pointer_checks)
continue;
+ /* PTA oracle will be unhapy of arg is not an pointer. */
if (!POINTER_TYPE_P (TREE_TYPE (arg)))
return true;
- /* ao_ref_init_from_ptr_and_range assumes that memory access
- starts by the pointed to location. If we did not track the
- offset it is possible that it starts before the actual
- pointer. */
- if (!access_node->parm_offset_known)
- {
- if (ptr_deref_may_alias_ref_p_1 (arg, ref))
- return true;
- }
- else
+ /* If we don't have base pointer, give up. */
+ if (!ref->ref && !ref->base)
+ continue;
+
+ ao_ref ref2;
+ if (access_node.get_ao_ref (stmt, &ref2))
{
- ao_ref ref2;
- poly_offset_int off = (poly_offset_int)access_node->offset
- + ((poly_offset_int)access_node->parm_offset
- << LOG2_BITS_PER_UNIT);
- poly_int64 off2;
- if (off.to_shwi (&off2))
- {
- ao_ref_init_from_ptr_and_range
- (&ref2, arg, true, off2,
- access_node->size,
- access_node->max_size);
- ref2.ref_alias_set = ref_set;
- ref2.base_alias_set = base_set;
- if (refs_may_alias_p_1 (&ref2, ref, tbaa_p))
- return true;
- }
- else if (ptr_deref_may_alias_ref_p_1 (arg, ref))
+ ref2.ref_alias_set = ref_node->ref;
+ ref2.base_alias_set = base_node->base;
+ if (refs_may_alias_p_1 (&ref2, ref, tbaa_p))
return true;
}
+ else if (ptr_deref_may_alias_ref_p_1 (arg, ref))
+ return true;
+
num_tests++;
}
}
diff --git a/gcc/tree-ssa-dse.c b/gcc/tree-ssa-dse.c
index 0e8c4ed1435..ce0083a6dab 100644
--- a/gcc/tree-ssa-dse.c
+++ b/gcc/tree-ssa-dse.c
@@ -1079,35 +1079,25 @@ dse_optimize_call (gimple_stmt_iterator *gsi, sbitmap live_bytes)
if (!summary || !summary->try_dse)
return false;
- modref_base_node <alias_set_type> *base_node;
- modref_ref_node <alias_set_type> *ref_node;
- modref_access_node *access_node;
- size_t i, j, k;
bool by_clobber_p = false;
/* Walk all memory writes and verify that they are dead. */
- FOR_EACH_VEC_SAFE_ELT (summary->stores->bases, i, base_node)
- FOR_EACH_VEC_SAFE_ELT (base_node->refs, j, ref_node)
- FOR_EACH_VEC_SAFE_ELT (ref_node->accesses, k, access_node)
+ for (auto base_node : summary->stores->bases)
+ for (auto ref_node : base_node->refs)
+ for (auto access_node : ref_node->accesses)
{
- gcc_checking_assert (access_node->parm_offset_known);
+ tree arg = access_node.get_call_arg (stmt);
- tree arg;
- if (access_node->parm_index == MODREF_STATIC_CHAIN_PARM)
- arg = gimple_call_chain (stmt);
- else
- arg = gimple_call_arg (stmt, access_node->parm_index);
+ if (!arg)
+ return false;
+
+ if (integer_zerop (arg) && flag_delete_null_pointer_checks)
+ continue;
ao_ref ref;
- poly_offset_int off = (poly_offset_int)access_node->offset
- + ((poly_offset_int)access_node->parm_offset
- << LOG2_BITS_PER_UNIT);
- poly_int64 off2;
- if (!off.to_shwi (&off2))
+
+ if (!access_node.get_ao_ref (stmt, &ref))
return false;
- ao_ref_init_from_ptr_and_range
- (&ref, arg, true, off2, access_node->size,
- access_node->max_size);
ref.ref_alias_set = ref_node->ref;
ref.base_alias_set = base_node->base;
@@ -25,6 +25,8 @@ along with GCC; see the file COPYING3. If not see
#include "tree.h"
#include "ipa-modref-tree.h"
#include "selftest.h"
+#include "tree-ssa-alias.h"
+#include "gimple.h"
/* Return true if both accesses are the same. */
bool
@@ -603,6 +605,39 @@ modref_access_node::dump (FILE *out)
fprintf (out, "\n");
}
+/* Return tree corresponding to parameter of the range in STMT. */
+tree
+modref_access_node::get_call_arg (const gcall *stmt) const
+{
+ if (parm_index == MODREF_UNKNOWN_PARM)
+ return NULL;
+ if (parm_index == MODREF_STATIC_CHAIN_PARM)
+ return gimple_call_chain (stmt);
+ /* MODREF_RETSLOT_PARM should not happen in access trees since the store
+ is seen explicitly in the caller. */
+ gcc_checking_assert (parm_index >= 0);
+ if (parm_index >= (int)gimple_call_num_args (stmt))
+ return NULL;
+ return gimple_call_arg (stmt, parm_index);
+}
+
+/* Return tree corresponding to parameter of the range in STMT. */
+bool
+modref_access_node::get_ao_ref (const gcall *stmt, ao_ref *ref) const
+{
+ tree arg;
+
+ if (!parm_offset_known || !(arg = get_call_arg (stmt)))
+ return false;
+ poly_offset_int off = (poly_offset_int)offset
+ + ((poly_offset_int)parm_offset << LOG2_BITS_PER_UNIT);
+ poly_int64 off2;
+ if (!off.to_shwi (&off2))
+ return false;
+ ao_ref_init_from_ptr_and_range (ref, arg, true, off2, size, max_size);
+ return true;
+}
+
#if CHECKING_P
namespace selftest {
@@ -77,7 +77,7 @@ struct GTY(()) modref_access_node
This has to be limited in order to keep dataflow finite. */
unsigned char adjustments;
- /* Return true if access node holds no useful info. */
+ /* Return true if access node holds some useful info. */
bool useful_p () const
{
return parm_index != MODREF_UNKNOWN_PARM;
@@ -88,10 +88,13 @@ struct GTY(()) modref_access_node
bool operator == (modref_access_node &a) const;
/* Return true if range info is useful. */
bool range_info_useful_p () const;
+ /* Return tree corresponding to parameter of the range in STMT. */
+ tree get_call_arg (const gcall *stmt) const;
+ /* Build ao_ref corresponding to the access and return true if succesful. */
+ bool get_ao_ref (const gcall *stmt, class ao_ref *ref) const;
/* Insert A into vector ACCESSES. Limit size of vector to MAX_ACCESSES and
if RECORD_ADJUSTMENT is true keep track of adjustment counts.
- Return 0 if nothing changed, 1 is insertion suceeded and -1 if
- failed. */
+ Return 0 if nothing changed, 1 is insertion suceeded and -1 if failed. */
static int insert (vec <modref_access_node, va_gc> *&accesses,
modref_access_node a, size_t max_accesses,
bool record_adjustments);
@@ -2535,13 +2535,10 @@ refs_output_dependent_p (tree store1, tree store2)
IF TBAA_P is true, use TBAA oracle. */
static bool
-modref_may_conflict (const gimple *stmt,
+modref_may_conflict (const gcall *stmt,
modref_tree <alias_set_type> *tt, ao_ref *ref, bool tbaa_p)
{
alias_set_type base_set, ref_set;
- modref_base_node <alias_set_type> *base_node;
- modref_ref_node <alias_set_type> *ref_node;
- size_t i, j, k;
if (tt->every_base)
return true;
@@ -2554,7 +2551,7 @@ modref_may_conflict (const gimple *stmt,
ref_set = ao_ref_alias_set (ref);
int num_tests = 0, max_tests = param_modref_max_tests;
- FOR_EACH_VEC_SAFE_ELT (tt->bases, i, base_node)
+ for (auto base_node : tt->bases)
{
if (tbaa_p && flag_strict_aliasing)
{
@@ -2569,7 +2566,7 @@ modref_may_conflict (const gimple *stmt,
if (base_node->every_ref)
return true;
- FOR_EACH_VEC_SAFE_ELT (base_node->refs, j, ref_node)
+ for (auto ref_node : base_node->refs)
{
/* Do not repeat same test as before. */
if ((ref_set != base_set || base_node->base != ref_node->ref)
@@ -2583,66 +2580,43 @@ modref_may_conflict (const gimple *stmt,
num_tests++;
}
- /* TBAA checks did not disambiguate, try to use base pointer, for
- that we however need to have ref->ref or ref->base. */
- if (ref_node->every_access || (!ref->ref && !ref->base))
+ if (ref_node->every_access)
return true;
- modref_access_node *access_node;
- FOR_EACH_VEC_SAFE_ELT (ref_node->accesses, k, access_node)
+ /* TBAA checks did not disambiguate, try individual accesses. */
+ for (auto access_node : ref_node->accesses)
{
if (num_tests >= max_tests)
return true;
- if (access_node->parm_index == MODREF_UNKNOWN_PARM
- || access_node->parm_index
- >= (int)gimple_call_num_args (stmt))
+ tree arg = access_node.get_call_arg (stmt);
+ if (!arg)
return true;
alias_stats.modref_baseptr_tests++;
- tree arg;
-
- if (access_node->parm_index == MODREF_STATIC_CHAIN_PARM)
- arg = gimple_call_chain (stmt);
- else
- arg = gimple_call_arg (stmt, access_node->parm_index);
if (integer_zerop (arg) && flag_delete_null_pointer_checks)
continue;
+ /* PTA oracle will be unhapy of arg is not an pointer. */
if (!POINTER_TYPE_P (TREE_TYPE (arg)))
return true;
- /* ao_ref_init_from_ptr_and_range assumes that memory access
- starts by the pointed to location. If we did not track the
- offset it is possible that it starts before the actual
- pointer. */
- if (!access_node->parm_offset_known)
- {
- if (ptr_deref_may_alias_ref_p_1 (arg, ref))
- return true;
- }
- else
+ /* If we don't have base pointer, give up. */
+ if (!ref->ref && !ref->base)
+ continue;
+
+ ao_ref ref2;
+ if (access_node.get_ao_ref (stmt, &ref2))
{
- ao_ref ref2;
- poly_offset_int off = (poly_offset_int)access_node->offset
- + ((poly_offset_int)access_node->parm_offset
- << LOG2_BITS_PER_UNIT);
- poly_int64 off2;
- if (off.to_shwi (&off2))
- {
- ao_ref_init_from_ptr_and_range
- (&ref2, arg, true, off2,
- access_node->size,
- access_node->max_size);
- ref2.ref_alias_set = ref_set;
- ref2.base_alias_set = base_set;
- if (refs_may_alias_p_1 (&ref2, ref, tbaa_p))
- return true;
- }
- else if (ptr_deref_may_alias_ref_p_1 (arg, ref))
+ ref2.ref_alias_set = ref_node->ref;
+ ref2.base_alias_set = base_node->base;
+ if (refs_may_alias_p_1 (&ref2, ref, tbaa_p))
return true;
}
+ else if (ptr_deref_may_alias_ref_p_1 (arg, ref))
+ return true;
+
num_tests++;
}
}
@@ -1079,35 +1079,25 @@ dse_optimize_call (gimple_stmt_iterator *gsi, sbitmap live_bytes)
if (!summary || !summary->try_dse)
return false;
- modref_base_node <alias_set_type> *base_node;
- modref_ref_node <alias_set_type> *ref_node;
- modref_access_node *access_node;
- size_t i, j, k;
bool by_clobber_p = false;
/* Walk all memory writes and verify that they are dead. */
- FOR_EACH_VEC_SAFE_ELT (summary->stores->bases, i, base_node)
- FOR_EACH_VEC_SAFE_ELT (base_node->refs, j, ref_node)
- FOR_EACH_VEC_SAFE_ELT (ref_node->accesses, k, access_node)
+ for (auto base_node : summary->stores->bases)
+ for (auto ref_node : base_node->refs)
+ for (auto access_node : ref_node->accesses)
{
- gcc_checking_assert (access_node->parm_offset_known);
+ tree arg = access_node.get_call_arg (stmt);
- tree arg;
- if (access_node->parm_index == MODREF_STATIC_CHAIN_PARM)
- arg = gimple_call_chain (stmt);
- else
- arg = gimple_call_arg (stmt, access_node->parm_index);
+ if (!arg)
+ return false;
+
+ if (integer_zerop (arg) && flag_delete_null_pointer_checks)
+ continue;
ao_ref ref;
- poly_offset_int off = (poly_offset_int)access_node->offset
- + ((poly_offset_int)access_node->parm_offset
- << LOG2_BITS_PER_UNIT);
- poly_int64 off2;
- if (!off.to_shwi (&off2))
+
+ if (!access_node.get_ao_ref (stmt, &ref))
return false;
- ao_ref_init_from_ptr_and_range
- (&ref, arg, true, off2, access_node->size,
- access_node->max_size);
ref.ref_alias_set = ref_node->ref;
ref.base_alias_set = base_node->base;