This exposes an interface for users to create new uses in RTL-SSA.
This is needed for updating uses after inserting a new store pair insn
in the aarch64 load/store pair fusion pass.
gcc/ChangeLog:
PR target/113070
* rtl-ssa/accesses.cc (function_info::create_use): New.
* rtl-ssa/changes.cc (function_info::finalize_new_accesses):
Handle temporary uses, ensure new uses end up referring to
permanent defs.
* rtl-ssa/functions.h (function_info::create_use): Declare.
---
gcc/rtl-ssa/accesses.cc | 10 ++++++++++
gcc/rtl-ssa/changes.cc | 24 +++++++++++++++++++-----
gcc/rtl-ssa/functions.h | 5 +++++
3 files changed, 34 insertions(+), 5 deletions(-)
diff --git a/gcc/rtl-ssa/accesses.cc b/gcc/rtl-ssa/accesses.cc
index ce4a8b8dc00..3f1304fc5bf 100644
--- a/gcc/rtl-ssa/accesses.cc
+++ b/gcc/rtl-ssa/accesses.cc
@@ -1466,6 +1466,16 @@ function_info::create_set (obstack_watermark &watermark,
return set;
}
+use_info *
+function_info::create_use (obstack_watermark &watermark,
+ insn_info *insn,
+ set_info *set)
+{
+ auto use = change_alloc<use_info> (watermark, insn, set->resource (), set);
+ use->m_is_temp = true;
+ return use;
+}
+
// Return true if ACCESS1 can represent ACCESS2 and if ACCESS2 can
// represent ACCESS1.
static bool
diff --git a/gcc/rtl-ssa/changes.cc b/gcc/rtl-ssa/changes.cc
index e538b637848..ce51d6ccd8d 100644
--- a/gcc/rtl-ssa/changes.cc
+++ b/gcc/rtl-ssa/changes.cc
@@ -538,7 +538,9 @@ function_info::finalize_new_accesses (insn_change &change, insn_info *pos)
unsigned int i = 0;
for (use_info *use : change.new_uses)
{
- if (!use->m_has_been_superceded)
+ if (use->m_is_temp)
+ use->m_has_been_superceded = true;
+ else if (!use->m_has_been_superceded)
{
use = allocate_temp<use_info> (insn, use->resource (), use->def ());
use->m_has_been_superceded = true;
@@ -609,15 +611,27 @@ function_info::finalize_new_accesses (insn_change &change, insn_info *pos)
m_temp_uses[i] = use = allocate<use_info> (*use);
use->m_is_temp = false;
set_info *def = use->def ();
- // Handle cases in which the value was previously not used
- // within the block.
- if (def && def->m_is_temp)
+ if (!def || !def->m_is_temp)
+ continue;
+
+ if (auto phi = dyn_cast<phi_info *> (def))
{
- phi_info *phi = as_a<phi_info *> (def);
+ // Handle cases in which the value was previously not used
+ // within the block.
gcc_assert (phi->is_degenerate ());
phi = create_degenerate_phi (phi->ebb (), phi->input_value (0));
use->set_def (phi);
}
+ else
+ {
+ // The temporary def may also be a set added with this change, in
+ // which case the permanent set is stored in the last_def link,
+ // and we need to update the use to refer to the permanent set.
+ gcc_assert (is_a<set_info *> (def));
+ auto perm_set = as_a<set_info *> (def->last_def ());
+ gcc_assert (!perm_set->is_temporary ());
+ use->set_def (perm_set);
+ }
}
}
diff --git a/gcc/rtl-ssa/functions.h b/gcc/rtl-ssa/functions.h
index 58d0b50ea83..962180e27d6 100644
--- a/gcc/rtl-ssa/functions.h
+++ b/gcc/rtl-ssa/functions.h
@@ -73,6 +73,11 @@ public:
insn_info *insn,
resource_info resource);
+ // Create a temporary use.
+ use_info *create_use (obstack_watermark &watermark,
+ insn_info *insn,
+ set_info *set);
+
// Create a temporary insn with code INSN_CODE and pattern PAT.
insn_info *create_insn (obstack_watermark &watermark,
rtx_code insn_code,
