[gcc(refs/vendors/redhat/heads/gcc-10-branch)] SRA: Total scalarization after access propagation [PR92706]
Jakub Jelinek
jakub@gcc.gnu.org
Thu Jan 30 20:56:00 GMT 2020
https://gcc.gnu.org/g:636e80eea24b780f1d5f4c14c58fc00001df8508
commit 636e80eea24b780f1d5f4c14c58fc00001df8508
Author: Martin Jambor <mjambor@suse.cz>
Date: Wed Jan 29 13:13:13 2020 +0100
SRA: Total scalarization after access propagation [PR92706]
2020-01-29 Martin Jambor <mjambor@suse.cz>
PR tree-optimization/92706
* tree-sra.c (struct access): Adjust comment of
grp_total_scalarization.
(find_access_in_subtree): Look for single children spanning an entire
access.
(scalarizable_type_p): Allow register accesses, adjust callers.
(completely_scalarize): Remove function.
(scalarize_elem): Likewise.
(create_total_scalarization_access): Likewise.
(sort_and_splice_var_accesses): Do not track total scalarization
flags.
(analyze_access_subtree): New parameter totally, adjust to new meaning
of grp_total_scalarization.
(analyze_access_trees): Pass new parameter to analyze_access_subtree.
(can_totally_scalarize_forest_p): New function.
(create_total_scalarization_access): Likewise.
(create_total_access_and_reshape): Likewise.
(total_should_skip_creating_access): Likewise.
(totally_scalarize_subtree): Likewise.
(analyze_all_variable_accesses): Perform total scalarization after
subaccess propagation using the new functions above.
(initialize_constant_pool_replacements): Output initializers by
traversing the access tree.
testsuite/
* gcc.dg/tree-ssa/pr92706-2.c: New test.
* gcc.dg/guality/pr59776.c: Xfail tests for s2.g.
Diff:
---
gcc/ChangeLog | 26 ++
gcc/testsuite/ChangeLog | 6 +
gcc/testsuite/gcc.dg/guality/pr59776.c | 4 +-
gcc/testsuite/gcc.dg/tree-ssa/pr92706-2.c | 19 +
gcc/tree-sra.c | 666 ++++++++++++++++++++++--------
5 files changed, 537 insertions(+), 184 deletions(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 16247a5..61da54d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,31 @@
2020-01-29 Martin Jambor <mjambor@suse.cz>
+ PR tree-optimization/92706
+ * tree-sra.c (struct access): Adjust comment of
+ grp_total_scalarization.
+ (find_access_in_subtree): Look for single children spanning an entire
+ access.
+ (scalarizable_type_p): Allow register accesses, adjust callers.
+ (completely_scalarize): Remove function.
+ (scalarize_elem): Likewise.
+ (create_total_scalarization_access): Likewise.
+ (sort_and_splice_var_accesses): Do not track total scalarization
+ flags.
+ (analyze_access_subtree): New parameter totally, adjust to new meaning
+ of grp_total_scalarization.
+ (analyze_access_trees): Pass new parameter to analyze_access_subtree.
+ (can_totally_scalarize_forest_p): New function.
+ (create_total_scalarization_access): Likewise.
+ (create_total_access_and_reshape): Likewise.
+ (total_should_skip_creating_access): Likewise.
+ (totally_scalarize_subtree): Likewise.
+ (analyze_all_variable_accesses): Perform total scalarization after
+ subaccess propagation using the new functions above.
+ (initialize_constant_pool_replacements): Output initializers by
+ traversing the access tree.
+
+2020-01-29 Martin Jambor <mjambor@suse.cz>
+
* tree-sra.c (verify_sra_access_forest): New function.
(verify_all_sra_access_forests): Likewise.
(create_artificial_child_access): Set parent.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0551884..3875820 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2020-01-29 Martin Jambor <mjambor@suse.cz>
+
+ PR tree-optimization/92706
+ * gcc.dg/tree-ssa/pr92706-2.c: New test.
+ * gcc.dg/guality/pr59776.c: Xfail tests for s2.g.
+
2020-01-28 Jan Hubicka <hubicka@ucw.cz>
* gcc.dg/tree-prof/indir-call-prof-2.c: New testcase.
diff --git a/gcc/testsuite/gcc.dg/guality/pr59776.c b/gcc/testsuite/gcc.dg/guality/pr59776.c
index 382abb6..6c1c816 100644
--- a/gcc/testsuite/gcc.dg/guality/pr59776.c
+++ b/gcc/testsuite/gcc.dg/guality/pr59776.c
@@ -12,11 +12,11 @@ foo (struct S *p)
struct S s1, s2; /* { dg-final { gdb-test pr59776.c:17 "s1.f" "5.0" } } */
s1 = *p; /* { dg-final { gdb-test pr59776.c:17 "s1.g" "6.0" } } */
s2 = s1; /* { dg-final { gdb-test pr59776.c:17 "s2.f" "0.0" } } */
- *(int *) &s2.f = 0; /* { dg-final { gdb-test pr59776.c:17 "s2.g" "6.0" } } */
+ *(int *) &s2.f = 0; /* { dg-final { gdb-test pr59776.c:17 "s2.g" "6.0" { xfail *-*-* } } } */
asm volatile (NOP : : : "memory"); /* { dg-final { gdb-test pr59776.c:20 "s1.f" "5.0" } } */
asm volatile (NOP : : : "memory"); /* { dg-final { gdb-test pr59776.c:20 "s1.g" "6.0" } } */
s2 = s1; /* { dg-final { gdb-test pr59776.c:20 "s2.f" "5.0" } } */
- asm volatile (NOP : : : "memory"); /* { dg-final { gdb-test pr59776.c:20 "s2.g" "6.0" } } */
+ asm volatile (NOP : : : "memory"); /* { dg-final { gdb-test pr59776.c:20 "s2.g" "6.0" { xfail *-*-* } } } */
asm volatile (NOP : : : "memory");
}
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr92706-2.c b/gcc/testsuite/gcc.dg/tree-ssa/pr92706-2.c
new file mode 100644
index 0000000..37ab976
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr92706-2.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-esra" } */
+
+typedef __UINT64_TYPE__ uint64_t;
+typedef __UINT32_TYPE__ uint32_t;
+struct S { uint32_t i[2]; } __attribute__((aligned(__alignof__(uint64_t))));
+typedef uint64_t my_int64 __attribute__((may_alias));
+uint64_t load (void *p)
+{
+ struct S u, v, w;
+ uint64_t tem;
+ tem = *(my_int64 *)p;
+ *(my_int64 *)&v = tem;
+ u = v;
+ w = u;
+ return *(my_int64 *)&w;
+}
+
+/* { dg-final { scan-tree-dump "Created a replacement for v" "esra" } } */
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
index 36106fe..2b08498 100644
--- a/gcc/tree-sra.c
+++ b/gcc/tree-sra.c
@@ -211,8 +211,11 @@ struct access
is not propagated in the access tree in any direction. */
unsigned grp_scalar_write : 1;
- /* Is this access an artificial one created to scalarize some record
- entirely? */
+ /* In a root of an access tree, true means that the entire tree should be
+ totally scalarized - that all scalar leafs should be scalarized and
+ non-root grp_total_scalarization accesses should be honored. Otherwise,
+ non-root accesses with grp_total_scalarization should never get scalar
+ replacements. */
unsigned grp_total_scalarization : 1;
/* Other passes of the analysis use this bit to make function
@@ -485,6 +488,15 @@ find_access_in_subtree (struct access *access, HOST_WIDE_INT offset,
access = child;
}
+ /* Total scalarization does not replace single field structures with their
+ single field but rather creates an access for them underneath. Look for
+ it. */
+ if (access)
+ while (access->first_child
+ && access->first_child->offset == offset
+ && access->first_child->size == size)
+ access = access->first_child;
+
return access;
}
@@ -856,7 +868,8 @@ create_access (tree expr, gimple *stmt, bool write)
static bool
scalarizable_type_p (tree type, bool const_decl)
{
- gcc_assert (!is_gimple_reg_type (type));
+ if (is_gimple_reg_type (type))
+ return true;
if (type_contains_placeholder_p (type))
return false;
@@ -871,8 +884,7 @@ scalarizable_type_p (tree type, bool const_decl)
if (DECL_BIT_FIELD (fld))
return false;
- if (!is_gimple_reg_type (ft)
- && !scalarizable_type_p (ft, const_decl))
+ if (!scalarizable_type_p (ft, const_decl))
return false;
}
@@ -902,8 +914,7 @@ scalarizable_type_p (tree type, bool const_decl)
return false;
tree elem = TREE_TYPE (type);
- if (!is_gimple_reg_type (elem)
- && !scalarizable_type_p (elem, const_decl))
+ if (!scalarizable_type_p (elem, const_decl))
return false;
return true;
}
@@ -912,114 +923,6 @@ scalarizable_type_p (tree type, bool const_decl)
}
}
-static void scalarize_elem (tree, HOST_WIDE_INT, HOST_WIDE_INT, bool, tree, tree);
-
-/* Create total_scalarization accesses for all scalar fields of a member
- of type DECL_TYPE conforming to scalarizable_type_p. BASE
- must be the top-most VAR_DECL representing the variable; within that,
- OFFSET locates the member and REF must be the memory reference expression for
- the member. */
-
-static void
-completely_scalarize (tree base, tree decl_type, HOST_WIDE_INT offset, tree ref)
-{
- switch (TREE_CODE (decl_type))
- {
- case RECORD_TYPE:
- for (tree fld = TYPE_FIELDS (decl_type); fld; fld = DECL_CHAIN (fld))
- if (TREE_CODE (fld) == FIELD_DECL)
- {
- HOST_WIDE_INT pos = offset + int_bit_position (fld);
- tree ft = TREE_TYPE (fld);
- tree nref = build3 (COMPONENT_REF, ft, ref, fld, NULL_TREE);
-
- scalarize_elem (base, pos, tree_to_uhwi (DECL_SIZE (fld)),
- TYPE_REVERSE_STORAGE_ORDER (decl_type),
- nref, ft);
- }
- break;
- case ARRAY_TYPE:
- {
- tree elemtype = TREE_TYPE (decl_type);
- tree elem_size = TYPE_SIZE (elemtype);
- gcc_assert (elem_size && tree_fits_shwi_p (elem_size));
- HOST_WIDE_INT el_size = tree_to_shwi (elem_size);
- gcc_assert (el_size > 0);
-
- tree minidx = TYPE_MIN_VALUE (TYPE_DOMAIN (decl_type));
- gcc_assert (TREE_CODE (minidx) == INTEGER_CST);
- tree maxidx = TYPE_MAX_VALUE (TYPE_DOMAIN (decl_type));
- /* Skip (some) zero-length arrays; others have MAXIDX == MINIDX - 1. */
- if (maxidx)
- {
- gcc_assert (TREE_CODE (maxidx) == INTEGER_CST);
- tree domain = TYPE_DOMAIN (decl_type);
- /* MINIDX and MAXIDX are inclusive, and must be interpreted in
- DOMAIN (e.g. signed int, whereas min/max may be size_int). */
- offset_int idx = wi::to_offset (minidx);
- offset_int max = wi::to_offset (maxidx);
- if (!TYPE_UNSIGNED (domain))
- {
- idx = wi::sext (idx, TYPE_PRECISION (domain));
- max = wi::sext (max, TYPE_PRECISION (domain));
- }
- for (int el_off = offset; idx <= max; ++idx)
- {
- tree nref = build4 (ARRAY_REF, elemtype,
- ref,
- wide_int_to_tree (domain, idx),
- NULL_TREE, NULL_TREE);
- scalarize_elem (base, el_off, el_size,
- TYPE_REVERSE_STORAGE_ORDER (decl_type),
- nref, elemtype);
- el_off += el_size;
- }
- }
- }
- break;
- default:
- gcc_unreachable ();
- }
-}
-
-/* Create total_scalarization accesses for a member of type TYPE, which must
- satisfy either is_gimple_reg_type or scalarizable_type_p. BASE must be the
- top-most VAR_DECL representing the variable; within that, POS and SIZE locate
- the member, REVERSE gives its torage order. and REF must be the reference
- expression for it. */
-
-static void
-scalarize_elem (tree base, HOST_WIDE_INT pos, HOST_WIDE_INT size, bool reverse,
- tree ref, tree type)
-{
- if (is_gimple_reg_type (type))
- {
- struct access *access = create_access_1 (base, pos, size);
- access->expr = ref;
- access->type = type;
- access->grp_total_scalarization = 1;
- access->reverse = reverse;
- /* Accesses for intraprocedural SRA can have their stmt NULL. */
- }
- else
- completely_scalarize (base, type, pos, ref);
-}
-
-/* Create a total_scalarization access for VAR as a whole. VAR must be of a
- RECORD_TYPE or ARRAY_TYPE conforming to scalarizable_type_p. */
-
-static void
-create_total_scalarization_access (tree var)
-{
- HOST_WIDE_INT size = tree_to_uhwi (DECL_SIZE (var));
- struct access *access;
-
- access = create_access_1 (var, 0, size);
- access->expr = var;
- access->type = TREE_TYPE (var);
- access->grp_total_scalarization = 1;
-}
-
/* Return true if REF has an VIEW_CONVERT_EXPR somewhere in it. */
static inline bool
@@ -2029,7 +1932,6 @@ sort_and_splice_var_accesses (tree var)
bool grp_assignment_read = access->grp_assignment_read;
bool grp_assignment_write = access->grp_assignment_write;
bool multiple_scalar_reads = false;
- bool total_scalarization = access->grp_total_scalarization;
bool grp_partial_lhs = access->grp_partial_lhs;
bool first_scalar = is_gimple_reg_type (access->type);
bool unscalarizable_region = access->grp_unscalarizable_region;
@@ -2081,7 +1983,6 @@ sort_and_splice_var_accesses (tree var)
grp_assignment_write |= ac2->grp_assignment_write;
grp_partial_lhs |= ac2->grp_partial_lhs;
unscalarizable_region |= ac2->grp_unscalarizable_region;
- total_scalarization |= ac2->grp_total_scalarization;
relink_to_new_repr (access, ac2);
/* If there are both aggregate-type and scalar-type accesses with
@@ -2122,9 +2023,7 @@ sort_and_splice_var_accesses (tree var)
access->grp_scalar_write = grp_scalar_write;
access->grp_assignment_read = grp_assignment_read;
access->grp_assignment_write = grp_assignment_write;
- access->grp_hint = total_scalarization
- || (multiple_scalar_reads && !constant_decl_p (var));
- access->grp_total_scalarization = total_scalarization;
+ access->grp_hint = multiple_scalar_reads && !constant_decl_p (var);
access->grp_partial_lhs = grp_partial_lhs;
access->grp_unscalarizable_region = unscalarizable_region;
access->grp_same_access_path = grp_same_access_path;
@@ -2420,15 +2319,16 @@ expr_with_var_bounded_array_refs_p (tree expr)
}
/* Analyze the subtree of accesses rooted in ROOT, scheduling replacements when
- both seeming beneficial and when ALLOW_REPLACEMENTS allows it. Also set all
- sorts of access flags appropriately along the way, notably always set
- grp_read and grp_assign_read according to MARK_READ and grp_write when
- MARK_WRITE is true.
+ both seeming beneficial and when ALLOW_REPLACEMENTS allows it. If TOTALLY
+ is set, we are totally scalarizing the aggregate. Also set all sorts of
+ access flags appropriately along the way, notably always set grp_read and
+ grp_assign_read according to MARK_READ and grp_write when MARK_WRITE is
+ true.
Creating a replacement for a scalar access is considered beneficial if its
- grp_hint is set (this means we are either attempting total scalarization or
- there is more than one direct read access) or according to the following
- table:
+ grp_hint ot TOTALLY is set (this means either that there is more than one
+ direct read access or that we are attempting total scalarization) or
+ according to the following table:
Access written to through a scalar type (once or more times)
|
@@ -2459,7 +2359,7 @@ expr_with_var_bounded_array_refs_p (tree expr)
static bool
analyze_access_subtree (struct access *root, struct access *parent,
- bool allow_replacements)
+ bool allow_replacements, bool totally)
{
struct access *child;
HOST_WIDE_INT limit = root->offset + root->size;
@@ -2477,8 +2377,6 @@ analyze_access_subtree (struct access *root, struct access *parent,
root->grp_write = 1;
if (parent->grp_assignment_write)
root->grp_assignment_write = 1;
- if (parent->grp_total_scalarization)
- root->grp_total_scalarization = 1;
if (!parent->grp_same_access_path)
root->grp_same_access_path = 0;
}
@@ -2493,10 +2391,10 @@ analyze_access_subtree (struct access *root, struct access *parent,
{
hole |= covered_to < child->offset;
sth_created |= analyze_access_subtree (child, root,
- allow_replacements && !scalar);
+ allow_replacements && !scalar,
+ totally);
root->grp_unscalarized_data |= child->grp_unscalarized_data;
- root->grp_total_scalarization &= child->grp_total_scalarization;
if (child->grp_covered)
covered_to += child->size;
else
@@ -2504,7 +2402,9 @@ analyze_access_subtree (struct access *root, struct access *parent,
}
if (allow_replacements && scalar && !root->first_child
- && (root->grp_hint
+ && (totally || !root->grp_total_scalarization)
+ && (totally
+ || root->grp_hint
|| ((root->grp_scalar_read || root->grp_assignment_read)
&& (root->grp_scalar_write || root->grp_assignment_write))))
{
@@ -2546,6 +2446,7 @@ analyze_access_subtree (struct access *root, struct access *parent,
{
if (allow_replacements
&& scalar && !root->first_child
+ && !root->grp_total_scalarization
&& (root->grp_scalar_write || root->grp_assignment_write)
&& !bitmap_bit_p (cannot_scalarize_away_bitmap,
DECL_UID (root->base)))
@@ -2566,7 +2467,7 @@ analyze_access_subtree (struct access *root, struct access *parent,
root->grp_total_scalarization = 0;
}
- if (!hole || root->grp_total_scalarization)
+ if (!hole || totally)
root->grp_covered = 1;
else if (root->grp_write || comes_initialized_p (root->base))
root->grp_unscalarized_data = 1; /* not covered and written to */
@@ -2582,7 +2483,8 @@ analyze_access_trees (struct access *access)
while (access)
{
- if (analyze_access_subtree (access, NULL, true))
+ if (analyze_access_subtree (access, NULL, true,
+ access->grp_total_scalarization))
ret = true;
access = access->next_grp;
}
@@ -2855,6 +2757,369 @@ propagate_all_subaccesses (void)
}
}
+/* Return true if the forest beginning with ROOT does not contain
+ unscalarizable regions or non-byte aligned accesses. */
+
+static bool
+can_totally_scalarize_forest_p (struct access *root)
+{
+ struct access *access = root;
+ do
+ {
+ if (access->grp_unscalarizable_region
+ || (access->offset % BITS_PER_UNIT) != 0
+ || (access->size % BITS_PER_UNIT) != 0
+ || (is_gimple_reg_type (access->type)
+ && access->first_child))
+ return false;
+
+ if (access->first_child)
+ access = access->first_child;
+ else if (access->next_sibling)
+ access = access->next_sibling;
+ else
+ {
+ while (access->parent && !access->next_sibling)
+ access = access->parent;
+ if (access->next_sibling)
+ access = access->next_sibling;
+ else
+ {
+ gcc_assert (access == root);
+ root = root->next_grp;
+ access = root;
+ }
+ }
+ }
+ while (access);
+ return true;
+}
+
+/* Create and return an ACCESS in PARENT spanning from POS with SIZE, TYPE and
+ reference EXPR for total scalarization purposes and mark it as such. Within
+ the children of PARENT, link it in between PTR and NEXT_SIBLING. */
+
+static struct access *
+create_total_scalarization_access (struct access *parent, HOST_WIDE_INT pos,
+ HOST_WIDE_INT size, tree type, tree expr,
+ struct access **ptr,
+ struct access *next_sibling)
+{
+ struct access *access = access_pool.allocate ();
+ memset (access, 0, sizeof (struct access));
+ access->base = parent->base;
+ access->offset = pos;
+ access->size = size;
+ access->expr = expr;
+ access->type = type;
+ access->parent = parent;
+ access->grp_write = parent->grp_write;
+ access->grp_total_scalarization = 1;
+ access->grp_hint = 1;
+ access->grp_same_access_path = path_comparable_for_same_access (expr);
+ access->reverse = reverse_storage_order_for_component_p (expr);
+
+ access->next_sibling = next_sibling;
+ *ptr = access;
+ return access;
+}
+
+/* Create and return an ACCESS in PARENT spanning from POS with SIZE, TYPE and
+ reference EXPR for total scalarization purposes and mark it as such, link it
+ at *PTR and reshape the tree so that those elements at *PTR and their
+ siblings which fall within the part described by POS and SIZE are moved to
+ be children of the new access. If a partial overlap is detected, return
+ NULL. */
+
+static struct access *
+create_total_access_and_reshape (struct access *parent, HOST_WIDE_INT pos,
+ HOST_WIDE_INT size, tree type, tree expr,
+ struct access **ptr)
+{
+ struct access **p = ptr;
+
+ while (*p && (*p)->offset < pos + size)
+ {
+ if ((*p)->offset + (*p)->size > pos + size)
+ return NULL;
+ p = &(*p)->next_sibling;
+ }
+
+ struct access *next_child = *ptr;
+ struct access *new_acc
+ = create_total_scalarization_access (parent, pos, size, type, expr,
+ ptr, *p);
+ if (p != ptr)
+ {
+ new_acc->first_child = next_child;
+ *p = NULL;
+ for (struct access *a = next_child; a; a = a->next_sibling)
+ a->parent = new_acc;
+ }
+ return new_acc;
+}
+
+static bool totally_scalarize_subtree (struct access *root);
+
+/* Return true if INNER is either the same type as OUTER or if it is the type
+ of a record field in OUTER at offset zero, possibly in nested
+ sub-records. */
+
+static bool
+access_and_field_type_match_p (tree outer, tree inner)
+{
+ if (TYPE_MAIN_VARIANT (outer) == TYPE_MAIN_VARIANT (inner))
+ return true;
+ if (TREE_CODE (outer) != RECORD_TYPE)
+ return false;
+ tree fld = TYPE_FIELDS (outer);
+ while (fld)
+ {
+ if (TREE_CODE (fld) == FIELD_DECL)
+ {
+ if (!zerop (DECL_FIELD_OFFSET (fld)))
+ return false;
+ if (TYPE_MAIN_VARIANT (TREE_TYPE (fld)) == inner)
+ return true;
+ if (TREE_CODE (TREE_TYPE (fld)) == RECORD_TYPE)
+ fld = TYPE_FIELDS (TREE_TYPE (fld));
+ else
+ return false;
+ }
+ else
+ fld = DECL_CHAIN (fld);
+ }
+ return false;
+}
+
+/* Return type of total_should_skip_creating_access indicating whether a total
+ scalarization access for a field/element should be created, whether it
+ already exists or whether the entire total scalarization has to fail. */
+
+enum total_sra_field_state {TOTAL_FLD_CREATE, TOTAL_FLD_DONE, TOTAL_FLD_FAILED};
+
+/* Do all the necessary steps in total scalarization when the given aggregate
+ type has a TYPE at POS with the given SIZE should be put into PARENT and
+ when we have processed all its siblings with smaller offsets up until and
+ including LAST_SEEN_SIBLING (which can be NULL).
+
+ If some further siblings are to be skipped, set *LAST_SEEN_SIBLING as
+ appropriate. Return TOTAL_FLD_CREATE id the caller should carry on with
+ creating a new access, TOTAL_FLD_DONE if access or accesses capable of
+ representing the described part of the aggregate for the purposes of total
+ scalarization already exist or TOTAL_FLD_FAILED if there is a problem which
+ prevents total scalarization from happening at all. */
+
+static enum total_sra_field_state
+total_should_skip_creating_access (struct access *parent,
+ struct access **last_seen_sibling,
+ tree type, HOST_WIDE_INT pos,
+ HOST_WIDE_INT size)
+{
+ struct access *next_child;
+ if (!*last_seen_sibling)
+ next_child = parent->first_child;
+ else
+ next_child = (*last_seen_sibling)->next_sibling;
+
+ /* First, traverse the chain of siblings until it points to an access with
+ offset at least equal to POS. Check all skipped accesses whether they
+ span the POS boundary and if so, return with a failure. */
+ while (next_child && next_child->offset < pos)
+ {
+ if (next_child->offset + next_child->size > pos)
+ return TOTAL_FLD_FAILED;
+ *last_seen_sibling = next_child;
+ next_child = next_child->next_sibling;
+ }
+
+ /* Now check whether next_child has exactly the right POS and SIZE and if so,
+ whether it can represent what we need and can be totally scalarized
+ itself. */
+ if (next_child && next_child->offset == pos
+ && next_child->size == size)
+ {
+ if (!is_gimple_reg_type (next_child->type)
+ && (!access_and_field_type_match_p (type, next_child->type)
+ || !totally_scalarize_subtree (next_child)))
+ return TOTAL_FLD_FAILED;
+
+ *last_seen_sibling = next_child;
+ return TOTAL_FLD_DONE;
+ }
+
+ /* If the child we're looking at would partially overlap, we just cannot
+ totally scalarize. */
+ if (next_child
+ && next_child->offset < pos + size
+ && next_child->offset + next_child->size > pos + size)
+ return TOTAL_FLD_FAILED;
+
+ if (is_gimple_reg_type (type))
+ {
+ /* We don't scalarize accesses that are children of other scalar type
+ accesses, so if we go on and create an access for a register type,
+ there should not be any pre-existing children. There are rare cases
+ where the requested type is a vector but we already have register
+ accesses for all its elements which is equally good. Detect that
+ situation or whether we need to bail out. */
+
+ HOST_WIDE_INT covered = pos;
+ bool skipping = false;
+ while (next_child
+ && next_child->offset + next_child->size <= pos + size)
+ {
+ if (next_child->offset != covered
+ || !is_gimple_reg_type (next_child->type))
+ return TOTAL_FLD_FAILED;
+
+ covered += next_child->size;
+ *last_seen_sibling = next_child;
+ next_child = next_child->next_sibling;
+ skipping = true;
+ }
+
+ if (skipping)
+ {
+ if (covered != pos + size)
+ return TOTAL_FLD_FAILED;
+ else
+ return TOTAL_FLD_DONE;
+ }
+ }
+
+ return TOTAL_FLD_CREATE;
+}
+
+/* Go over sub-tree rooted in ROOT and attempt to create scalar accesses
+ spanning all uncovered areas covered by ROOT, return false if the attempt
+ failed. All created accesses will have grp_unscalarizable_region set (and
+ should be ignored if the function returns false). */
+
+static bool
+totally_scalarize_subtree (struct access *root)
+{
+ gcc_checking_assert (!root->grp_unscalarizable_region);
+ gcc_checking_assert (!is_gimple_reg_type (root->type));
+
+ struct access *last_seen_sibling = NULL;
+
+ switch (TREE_CODE (root->type))
+ {
+ case RECORD_TYPE:
+ for (tree fld = TYPE_FIELDS (root->type); fld; fld = DECL_CHAIN (fld))
+ if (TREE_CODE (fld) == FIELD_DECL)
+ {
+ tree ft = TREE_TYPE (fld);
+ HOST_WIDE_INT fsize = tree_to_uhwi (DECL_SIZE (fld));
+ if (!fsize)
+ continue;
+
+ HOST_WIDE_INT pos = root->offset + int_bit_position (fld);
+ enum total_sra_field_state
+ state = total_should_skip_creating_access (root,
+ &last_seen_sibling,
+ ft, pos, fsize);
+ switch (state)
+ {
+ case TOTAL_FLD_FAILED:
+ return false;
+ case TOTAL_FLD_DONE:
+ continue;
+ case TOTAL_FLD_CREATE:
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ struct access **p = (last_seen_sibling
+ ? &last_seen_sibling->next_sibling
+ : &root->first_child);
+ tree nref = build3 (COMPONENT_REF, ft, root->expr, fld, NULL_TREE);
+ struct access *new_child
+ = create_total_access_and_reshape (root, pos, fsize, ft, nref, p);
+ if (!new_child)
+ return false;
+
+ if (!is_gimple_reg_type (ft)
+ && !totally_scalarize_subtree (new_child))
+ return false;
+ last_seen_sibling = new_child;
+ }
+ break;
+ case ARRAY_TYPE:
+ {
+ tree elemtype = TREE_TYPE (root->type);
+ tree elem_size = TYPE_SIZE (elemtype);
+ gcc_assert (elem_size && tree_fits_shwi_p (elem_size));
+ HOST_WIDE_INT el_size = tree_to_shwi (elem_size);
+ gcc_assert (el_size > 0);
+
+ tree minidx = TYPE_MIN_VALUE (TYPE_DOMAIN (root->type));
+ gcc_assert (TREE_CODE (minidx) == INTEGER_CST);
+ tree maxidx = TYPE_MAX_VALUE (TYPE_DOMAIN (root->type));
+ /* Skip (some) zero-length arrays; others have MAXIDX == MINIDX - 1. */
+ if (!maxidx)
+ goto out;
+ gcc_assert (TREE_CODE (maxidx) == INTEGER_CST);
+ tree domain = TYPE_DOMAIN (root->type);
+ /* MINIDX and MAXIDX are inclusive, and must be interpreted in
+ DOMAIN (e.g. signed int, whereas min/max may be size_int). */
+ offset_int idx = wi::to_offset (minidx);
+ offset_int max = wi::to_offset (maxidx);
+ if (!TYPE_UNSIGNED (domain))
+ {
+ idx = wi::sext (idx, TYPE_PRECISION (domain));
+ max = wi::sext (max, TYPE_PRECISION (domain));
+ }
+ for (HOST_WIDE_INT pos = root->offset;
+ idx <= max;
+ pos += el_size, ++idx)
+ {
+ enum total_sra_field_state
+ state = total_should_skip_creating_access (root,
+ &last_seen_sibling,
+ elemtype, pos,
+ el_size);
+ switch (state)
+ {
+ case TOTAL_FLD_FAILED:
+ return false;
+ case TOTAL_FLD_DONE:
+ continue;
+ case TOTAL_FLD_CREATE:
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ struct access **p = (last_seen_sibling
+ ? &last_seen_sibling->next_sibling
+ : &root->first_child);
+ tree nref = build4 (ARRAY_REF, elemtype, root->expr,
+ wide_int_to_tree (domain, idx),
+ NULL_TREE, NULL_TREE);
+ struct access *new_child
+ = create_total_access_and_reshape (root, pos, el_size, elemtype,
+ nref, p);
+ if (!new_child)
+ return false;
+
+ if (!is_gimple_reg_type (elemtype)
+ && !totally_scalarize_subtree (new_child))
+ return false;
+ last_seen_sibling = new_child;
+ }
+ }
+ break;
+ default:
+ gcc_unreachable ();
+ }
+
+ out:
+ return true;
+}
+
/* Go through all accesses collected throughout the (intraprocedural) analysis
stage, exclude overlapping ones, identify representatives and build trees
out of them, making decisions about scalarization on the way. Return true
@@ -2867,8 +3132,22 @@ analyze_all_variable_accesses (void)
bitmap tmp = BITMAP_ALLOC (NULL);
bitmap_iterator bi;
unsigned i;
- bool optimize_speed_p = !optimize_function_for_size_p (cfun);
+ bitmap_copy (tmp, candidate_bitmap);
+ EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, bi)
+ {
+ tree var = candidate (i);
+ struct access *access;
+
+ access = sort_and_splice_var_accesses (var);
+ if (!access || !build_access_trees (access))
+ disqualify_candidate (var,
+ "No or inhibitingly overlapping accesses.");
+ }
+
+ propagate_all_subaccesses ();
+
+ bool optimize_speed_p = !optimize_function_for_size_p (cfun);
/* If the user didn't set PARAM_SRA_MAX_SCALARIZATION_SIZE_<...>,
fall back to a target default. */
unsigned HOST_WIDE_INT max_scalarization_size
@@ -2884,7 +3163,6 @@ analyze_all_variable_accesses (void)
if (global_options_set.x_param_sra_max_scalarization_size_size)
max_scalarization_size = param_sra_max_scalarization_size_size;
}
-
max_scalarization_size *= BITS_PER_UNIT;
EXECUTE_IF_SET_IN_BITMAP (candidate_bitmap, 0, i, bi)
@@ -2892,46 +3170,56 @@ analyze_all_variable_accesses (void)
&& !bitmap_bit_p (cannot_scalarize_away_bitmap, i))
{
tree var = candidate (i);
+ if (!VAR_P (var))
+ continue;
- if (VAR_P (var) && scalarizable_type_p (TREE_TYPE (var),
- constant_decl_p (var)))
+ if (tree_to_uhwi (TYPE_SIZE (TREE_TYPE (var))) > max_scalarization_size)
{
- if (tree_to_uhwi (TYPE_SIZE (TREE_TYPE (var)))
- <= max_scalarization_size)
- {
- create_total_scalarization_access (var);
- completely_scalarize (var, TREE_TYPE (var), 0, var);
- statistics_counter_event (cfun,
- "Totally-scalarized aggregates", 1);
- if (dump_file && (dump_flags & TDF_DETAILS))
- {
- fprintf (dump_file, "Will attempt to totally scalarize ");
- print_generic_expr (dump_file, var);
- fprintf (dump_file, " (UID: %u): \n", DECL_UID (var));
- }
- }
- else if (dump_file && (dump_flags & TDF_DETAILS))
+ if (dump_file && (dump_flags & TDF_DETAILS))
{
fprintf (dump_file, "Too big to totally scalarize: ");
print_generic_expr (dump_file, var);
fprintf (dump_file, " (UID: %u)\n", DECL_UID (var));
}
+ continue;
}
- }
- bitmap_copy (tmp, candidate_bitmap);
- EXECUTE_IF_SET_IN_BITMAP (tmp, 0, i, bi)
- {
- tree var = candidate (i);
- struct access *access;
+ bool all_types_ok = true;
+ for (struct access *access = get_first_repr_for_decl (var);
+ access;
+ access = access->next_grp)
+ if (!can_totally_scalarize_forest_p (access)
+ || !scalarizable_type_p (access->type, constant_decl_p (var)))
+ {
+ all_types_ok = false;
+ break;
+ }
+ if (!all_types_ok)
+ continue;
- access = sort_and_splice_var_accesses (var);
- if (!access || !build_access_trees (access))
- disqualify_candidate (var,
- "No or inhibitingly overlapping accesses.");
- }
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "Will attempt to totally scalarize ");
+ print_generic_expr (dump_file, var);
+ fprintf (dump_file, " (UID: %u): \n", DECL_UID (var));
+ }
+ bool scalarized = true;
+ for (struct access *access = get_first_repr_for_decl (var);
+ access;
+ access = access->next_grp)
+ if (!is_gimple_reg_type (access->type)
+ && !totally_scalarize_subtree (access))
+ {
+ scalarized = false;
+ break;
+ }
- propagate_all_subaccesses ();
+ if (scalarized)
+ for (struct access *access = get_first_repr_for_decl (var);
+ access;
+ access = access->next_grp)
+ access->grp_total_scalarization = true;
+ }
if (flag_checking)
verify_all_sra_access_forests ();
@@ -3804,25 +4092,39 @@ initialize_constant_pool_replacements (void)
tree var = candidate (i);
if (!constant_decl_p (var))
continue;
- vec<access_p> *access_vec = get_base_access_vector (var);
- if (!access_vec)
- continue;
- for (unsigned i = 0; i < access_vec->length (); i++)
+
+ struct access *access = get_first_repr_for_decl (var);
+
+ while (access)
{
- struct access *access = (*access_vec)[i];
- if (!access->replacement_decl)
- continue;
- gassign *stmt
- = gimple_build_assign (get_access_replacement (access),
- unshare_expr (access->expr));
- if (dump_file && (dump_flags & TDF_DETAILS))
+ if (access->replacement_decl)
{
- fprintf (dump_file, "Generating constant initializer: ");
- print_gimple_stmt (dump_file, stmt, 0);
- fprintf (dump_file, "\n");
+ gassign *stmt
+ = gimple_build_assign (get_access_replacement (access),
+ unshare_expr (access->expr));
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "Generating constant initializer: ");
+ print_gimple_stmt (dump_file, stmt, 0);
+ fprintf (dump_file, "\n");
+ }
+ gsi_insert_after (&gsi, stmt, GSI_NEW_STMT);
+ update_stmt (stmt);
+ }
+
+ if (access->first_child)
+ access = access->first_child;
+ else if (access->next_sibling)
+ access = access->next_sibling;
+ else
+ {
+ while (access->parent && !access->next_sibling)
+ access = access->parent;
+ if (access->next_sibling)
+ access = access->next_sibling;
+ else
+ access = access->next_grp;
}
- gsi_insert_after (&gsi, stmt, GSI_NEW_STMT);
- update_stmt (stmt);
}
}
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