static bool
copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
{
int p1, p2, p3;
tree root1, root2;
tree rep1, rep2;
bool ign1, ign2, abnorm;
gcc_assert (TREE_CODE (var1) == SSA_NAME);
gcc_assert (TREE_CODE (var2) == SSA_NAME);
register_ssa_partition (map, var1);
register_ssa_partition (map, var2);
p1 = partition_find (map->var_partition, SSA_NAME_VERSION (var1));
p2 = partition_find (map->var_partition, SSA_NAME_VERSION (var2));
if (debug)
{
fprintf (debug, "Try : ");
print_generic_expr (debug, var1, TDF_SLIM);
fprintf (debug, "(P%d) & ", p1);
print_generic_expr (debug, var2, TDF_SLIM);
fprintf (debug, "(P%d)", p2);
}
gcc_assert (p1 != NO_PARTITION);
gcc_assert (p2 != NO_PARTITION);
if (p1 == p2)
{
if (debug)
fprintf (debug, " : Already coalesced.\n");
return false;
}
rep1 = partition_to_var (map, p1);
rep2 = partition_to_var (map, p2);
root1 = SSA_NAME_VAR (rep1);
root2 = SSA_NAME_VAR (rep2);
if (!root1 && !root2)
return false;
/* Don't coalesce if one of the variables occurs in an abnormal PHI. */
abnorm = (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rep1)
|| SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rep2));
if (abnorm)
{
if (debug)
fprintf (debug, " : Abnormal PHI barrier. No coalesce.\n");
return false;
}
/* Partitions already have the same root, simply merge them. */
if (root1 == root2)
{
p1 = partition_union (map->var_partition, p1, p2);
if (debug)
fprintf (debug, " : Same root, coalesced --> P%d.\n", p1);
return false;
}
/* Never attempt to coalesce 2 different parameters. */
if ((root1 && TREE_CODE (root1) == PARM_DECL)
&& (root2 && TREE_CODE (root2) == PARM_DECL))
{
if (debug)
fprintf (debug, " : 2 different PARM_DECLS. No coalesce.\n");
return false;
}
if ((root1 && TREE_CODE (root1) == RESULT_DECL)
!= (root2 && TREE_CODE (root2) == RESULT_DECL))
{
if (debug)
fprintf (debug, " : One root a RESULT_DECL. No coalesce.\n");
return false;
}
ign1 = !root1 || (TREE_CODE (root1) == VAR_DECL && DECL_IGNORED_P (root1));
ign2 = !root2 || (TREE_CODE (root2) == VAR_DECL && DECL_IGNORED_P (root2));
/* Refrain from coalescing user variables, if requested. */
if (!ign1 && !ign2)
{
if (flag_ssa_coalesce_vars && DECL_FROM_INLINE (root2))
ign2 = true;
else if (flag_ssa_coalesce_vars && DECL_FROM_INLINE (root1))
ign1 = true;
else if (flag_ssa_coalesce_vars != 2)
{
if (debug)
fprintf (debug, " : 2 different USER vars. No coalesce.\n");
return false;
}
else
ign2 = true;
}
/* If both values have default defs, we can't coalesce. If only one has a
tag, make sure that variable is the new root partition. */
if (root1 && ssa_default_def (cfun, root1))
{
if (root2 && ssa_default_def (cfun, root2))
{
if (debug)
fprintf (debug, " : 2 default defs. No coalesce.\n");
return false;
}
else
{
ign2 = true;
ign1 = false;
}
}
else if (root2 && ssa_default_def (cfun, root2))
{
ign1 = true;
ign2 = false;
}
/* Do not coalesce if we cannot assign a symbol to the partition. */
if (!(!ign2 && root2)
&& !(!ign1 && root1))
{
if (debug)
fprintf (debug, " : Choosen variable has no root. No coalesce.\n");
return false;
}
/* Don't coalesce if the new chosen root variable would be read-only.
If both ign1 && ign2, then the root var of the larger partition
wins, so reject in that case if any of the root vars is TREE_READONLY.
Otherwise reject only if the root var, on which replace_ssa_name_symbol
will be called below, is readonly. */
if (((root1 && TREE_READONLY (root1)) && ign2)
|| ((root2 && TREE_READONLY (root2)) && ign1))
{
if (debug)
fprintf (debug, " : Readonly variable. No coalesce.\n");
return false;
}
/* Don't coalesce if the two variables aren't type compatible . */
if (!types_compatible_p (TREE_TYPE (var1), TREE_TYPE (var2))
/* There is a disconnect between the middle-end type-system and
VRP, avoid coalescing enum types with different bounds. */
|| ((TREE_CODE (TREE_TYPE (var1)) == ENUMERAL_TYPE
|| TREE_CODE (TREE_TYPE (var2)) == ENUMERAL_TYPE)
&& TREE_TYPE (var1) != TREE_TYPE (var2)))
{
if (debug)
fprintf (debug, " : Incompatible types. No coalesce.\n");
return false;
}
/* Merge the two partitions. */
p3 = partition_union (map->var_partition, p1, p2);
/* Set the root variable of the partition to the better choice, if there is
one. */
if (!ign2 && root2)
replace_ssa_name_symbol (partition_to_var (map, p3), root2);
else if (!ign1 && root1)
replace_ssa_name_symbol (partition_to_var (map, p3), root1);
else
gcc_unreachable ();
if (debug)
{
fprintf (debug, " --> P%d ", p3);
print_generic_expr (debug, SSA_NAME_VAR (partition_to_var (map, p3)),
TDF_SLIM);
fprintf (debug, "\n");
}
return true;
}
static bool
copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
{
int p1, p2, p3;
tree root1, root2;
tree rep1, rep2;
bool ign1, ign2, abnorm;
gcc_assert (TREE_CODE (var1) == SSA_NAME);
gcc_assert (TREE_CODE (var2) == SSA_NAME);
register_ssa_partition (map, var1);
register_ssa_partition (map, var2);
p1 = partition_find (map->var_partition, SSA_NAME_VERSION (var1));
p2 = partition_find (map->var_partition, SSA_NAME_VERSION (var2));
if (debug)
{
fprintf (debug, "Try : ");
print_generic_expr (debug, var1, TDF_SLIM);
fprintf (debug, "(P%d) & ", p1);
print_generic_expr (debug, var2, TDF_SLIM);
fprintf (debug, "(P%d)", p2);
}
gcc_assert (p1 != NO_PARTITION);
gcc_assert (p2 != NO_PARTITION);
rep1 = partition_to_var (map, p1);
rep2 = partition_to_var (map, p2);
root1 = SSA_NAME_VAR (rep1);
root2 = SSA_NAME_VAR (rep2);
if (p1 == p2)
{
if (debug)
fprintf (debug, " : Already coalesced.\n");
return false;
}
/* Don't coalesce if one of the variables occurs in an abnormal PHI. */
abnorm = (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rep1)
|| SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rep2));
if (abnorm)
{
if (debug)
fprintf (debug, " : Abnormal PHI barrier. No coalesce.\n");
return false;
}
/* Partitions already have the same root, simply merge them. */
if (root1 == root2)
{
p1 = partition_union (map->var_partition, p1, p2);
if (debug)
fprintf (debug, " : Same root, coalesced --> P%d.\n", p1);
return false;
}
/* Never attempt to coalesce 2 difference parameters. */
if (TREE_CODE (root1) == PARM_DECL && TREE_CODE (root2) == PARM_DECL)
{
if (debug)
fprintf (debug, " : 2 different PARM_DECLS. No coalesce.\n");
return false;
}
if ((TREE_CODE (root1) == RESULT_DECL) != (TREE_CODE (root2) == RESULT_DECL))
{
if (debug)
fprintf (debug, " : One root a RESULT_DECL. No coalesce.\n");
return false;
}
ign1 = TREE_CODE (root1) == VAR_DECL && DECL_IGNORED_P (root1);
ign2 = TREE_CODE (root2) == VAR_DECL && DECL_IGNORED_P (root2);
/* Never attempt to coalesce 2 user variables unless one is an inline
variable. */
if (!ign1 && !ign2)
{
if (DECL_FROM_INLINE (root2))
ign2 = true;
else if (DECL_FROM_INLINE (root1))
ign1 = true;
else
{
if (debug)
fprintf (debug, " : 2 different USER vars. No coalesce.\n");
return false;
}
}
/* If both values have default defs, we can't coalesce. If only one has a
tag, make sure that variable is the new root partition. */
if (gimple_default_def (cfun, root1))
{
if (gimple_default_def (cfun, root2))
{
if (debug)
fprintf (debug, " : 2 default defs. No coalesce.\n");
return false;
}
else
{
ign2 = true;
ign1 = false;
}
}
else if (gimple_default_def (cfun, root2))
{
ign1 = true;
ign2 = false;
}
/* Don't coalesce if the two variables aren't type compatible. */
if (!types_compatible_p (TREE_TYPE (root1), TREE_TYPE (root2)))
{
if (debug)
fprintf (debug, " : Incompatible types. No coalesce.\n");
return false;
}
/* Merge the two partitions. */
p3 = partition_union (map->var_partition, p1, p2);
/* Set the root variable of the partition to the better choice, if there is
one. */
if (!ign2)
replace_ssa_name_symbol (partition_to_var (map, p3), root2);
else if (!ign1)
replace_ssa_name_symbol (partition_to_var (map, p3), root1);
if (debug)
{
fprintf (debug, " --> P%d ", p3);
print_generic_expr (debug, SSA_NAME_VAR (partition_to_var (map, p3)),
TDF_SLIM);
fprintf (debug, "\n");
}
return true;
}