/* Alias analysis for GNU C
- Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
+ Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
Free Software Foundation, Inc.
Contributed by John Carr (jfc@mit.edu).
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
#include "config.h"
#include "system.h"
#include "tree.h"
#include "tm_p.h"
#include "function.h"
-#include "expr.h"
+#include "alias.h"
+#include "emit-rtl.h"
#include "regs.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "target.h"
#include "cgraph.h"
#include "varray.h"
+#include "tree-pass.h"
+#include "ipa-type-escape.h"
+
+/* The aliasing API provided here solves related but different problems:
+
+ Say there exists (in c)
+
+ struct X {
+ struct Y y1;
+ struct Z z2;
+ } x1, *px1, *px2;
+
+ struct Y y2, *py;
+ struct Z z2, *pz;
+
+
+ py = &px1.y1;
+ px2 = &x1;
+
+ Consider the four questions:
+
+ Can a store to x1 interfere with px2->y1?
+ Can a store to x1 interfere with px2->z2?
+ (*px2).z2
+ Can a store to x1 change the value pointed to by with py?
+ Can a store to x1 change the value pointed to by with pz?
+
+ The answer to these questions can be yes, yes, yes, and maybe.
+
+ The first two questions can be answered with a simple examination
+ of the type system. If structure X contains a field of type Y then
+ a store thru a pointer to an X can overwrite any field that is
+ contained (recursively) in an X (unless we know that px1 != px2).
+
+ The last two of the questions can be solved in the same way as the
+ first two questions but this is too conservative. The observation
+ is that in some cases analysis we can know if which (if any) fields
+ are addressed and if those addresses are used in bad ways. This
+ analysis may be language specific. In C, arbitrary operations may
+ be applied to pointers. However, there is some indication that
+ this may be too conservative for some C++ types.
+
+ The pass ipa-type-escape does this analysis for the types whose
+ instances do not escape across the compilation boundary.
+
+ Historically in GCC, these two problems were combined and a single
+ data structure was used to represent the solution to these
+ problems. We now have two similar but different data structures,
+ The data structure to solve the last two question is similar to the
+ first, but does not contain have the fields in it whose address are
+ never taken. For types that do escape the compilation unit, the
+ data structures will have identical information.
+*/
/* The alias sets assigned to MEMs assist the back-end in determining
which MEMs can alias which other MEMs. In general, two MEMs in
However, this is no actual entry for alias set zero. It is an
error to attempt to explicitly construct a subset of zero. */
-typedef struct alias_set_entry
+struct alias_set_entry GTY(())
{
/* The alias set number, as stored in MEM_ALIAS_SET. */
HOST_WIDE_INT alias_set;
continuing our example above, the children here will be all of
`int', `double', `float', and `struct S'. */
- splay_tree children;
+ splay_tree GTY((param1_is (int), param2_is (int))) children;
/* Nonzero if would have a child of zero: this effectively makes this
alias set the same as alias set zero. */
int has_zero_child;
-} *alias_set_entry;
+};
+typedef struct alias_set_entry *alias_set_entry;
static int rtx_equal_for_memref_p (rtx, rtx);
static rtx find_symbolic_term (rtx);
static tree decl_for_component_ref (tree);
static rtx adjust_offset_for_component_ref (tree, rtx);
static int nonoverlapping_memrefs_p (rtx, rtx);
-static int write_dependence_p (rtx, rtx, int, int);
-
-static int nonlocal_mentioned_p_1 (rtx *, void *);
-static int nonlocal_mentioned_p (rtx);
-static int nonlocal_referenced_p_1 (rtx *, void *);
-static int nonlocal_referenced_p (rtx);
-static int nonlocal_set_p_1 (rtx *, void *);
-static int nonlocal_set_p (rtx);
+static int write_dependence_p (rtx, rtx, int);
+
static void memory_modified_1 (rtx, rtx, void *);
+static void record_alias_subset (HOST_WIDE_INT, HOST_WIDE_INT);
/* Set up all info needed to perform alias analysis on memory references. */
current function performs nonlocal memory memory references for the
purposes of marking the function as a constant function. */
-static GTY((length ("reg_base_value_size"))) rtx *reg_base_value;
+static GTY(()) varray_type reg_base_value;
static rtx *new_reg_base_value;
-static unsigned int reg_base_value_size; /* size of reg_base_value array */
+
+/* We preserve the copy of old array around to avoid amount of garbage
+ produced. About 8% of garbage produced were attributed to this
+ array. */
+static GTY((deletable)) varray_type old_reg_base_value;
/* Static hunks of RTL used by the aliasing code; these are initialized
once per function to avoid unnecessary RTL allocations. */
static GTY (()) rtx static_reg_base_value[FIRST_PSEUDO_REGISTER];
#define REG_BASE_VALUE(X) \
- (REGNO (X) < reg_base_value_size \
- ? reg_base_value[REGNO (X)] : 0)
+ (reg_base_value && REGNO (X) < VARRAY_SIZE (reg_base_value) \
+ ? VARRAY_RTX (reg_base_value, REGNO (X)) : 0)
/* Vector of known invariant relationships between registers. Set in
loop unrolling. Indexed by register number, if nonzero the value
Because this array contains only pseudo registers it has no effect
after reload. */
-static rtx *alias_invariant;
+static GTY((length("alias_invariant_size"))) rtx *alias_invariant;
+static GTY(()) unsigned int alias_invariant_size;
/* Vector indexed by N giving the initial (unchanging) value known for
- pseudo-register N. This array is initialized in
- init_alias_analysis, and does not change until end_alias_analysis
- is called. */
-rtx *reg_known_value;
+ pseudo-register N. This array is initialized in init_alias_analysis,
+ and does not change until end_alias_analysis is called. */
+static GTY((length("reg_known_value_size"))) rtx *reg_known_value;
/* Indicates number of valid entries in reg_known_value. */
-static unsigned int reg_known_value_size;
+static GTY(()) unsigned int reg_known_value_size;
/* Vector recording for each reg_known_value whether it is due to a
REG_EQUIV note. Future passes (viz., reload) may replace the
REG_EQUIV notes. One could argue that the REG_EQUIV notes are
wrong, but solving the problem in the scheduler will likely give
better code, so we do it here. */
-char *reg_known_equiv_p;
+static bool *reg_known_equiv_p;
/* True when scanning insns from the start of the rtl to the
NOTE_INSN_FUNCTION_BEG note. */
static bool copying_arguments;
/* The splay-tree used to store the various alias set entries. */
-varray_type alias_sets;
+static GTY ((param_is (struct alias_set_entry))) varray_type alias_sets;
\f
/* Returns a pointer to the alias set entry for ALIAS_SET, if there is
such an entry, or NULL otherwise. */
static inline int
mems_in_disjoint_alias_sets_p (rtx mem1, rtx mem2)
{
-#ifdef ENABLE_CHECKING
/* Perform a basic sanity check. Namely, that there are no alias sets
if we're not using strict aliasing. This helps to catch bugs
whereby someone uses PUT_CODE, but doesn't clear MEM_ALIAS_SET, or
gen_rtx_MEM, and the MEM_ALIAS_SET is not cleared. If we begin to
use alias sets to indicate that spilled registers cannot alias each
other, we might need to remove this check. */
- if (! flag_strict_aliasing
- && (MEM_ALIAS_SET (mem1) != 0 || MEM_ALIAS_SET (mem2) != 0))
- abort ();
-#endif
+ gcc_assert (flag_strict_aliasing
+ || (!MEM_ALIAS_SET (mem1) && !MEM_ALIAS_SET (mem2)));
return ! alias_sets_conflict_p (MEM_ALIAS_SET (mem1), MEM_ALIAS_SET (mem2));
}
child of the other. Therefore, they cannot alias. */
return 0;
}
-\f
-/* Return 1 if TYPE is a RECORD_TYPE, UNION_TYPE, or QUAL_UNION_TYPE and has
- has any readonly fields. If any of the fields have types that
- contain readonly fields, return true as well. */
+
+/* Return 1 if the two specified alias sets might conflict, or if any subtype
+ of these alias sets might conflict. */
int
-readonly_fields_p (tree type)
+alias_sets_might_conflict_p (HOST_WIDE_INT set1, HOST_WIDE_INT set2)
{
- tree field;
-
- if (TREE_CODE (type) != RECORD_TYPE && TREE_CODE (type) != UNION_TYPE
- && TREE_CODE (type) != QUAL_UNION_TYPE)
- return 0;
-
- for (field = TYPE_FIELDS (type); field != 0; field = TREE_CHAIN (field))
- if (TREE_CODE (field) == FIELD_DECL
- && (TREE_READONLY (field)
- || readonly_fields_p (TREE_TYPE (field))))
- return 1;
+ if (set1 == 0 || set2 == 0 || set1 == set2)
+ return 1;
return 0;
}
+
\f
/* Return 1 if any MEM object of type T1 will always conflict (using the
dependency routines in this file) with any MEM object of type T2.
if (t1 == 0 && t2 == 0)
return 0;
- /* If one or the other has readonly fields or is readonly,
- then they may not conflict. */
- if ((t1 != 0 && readonly_fields_p (t1))
- || (t2 != 0 && readonly_fields_p (t2))
- || (t1 != 0 && lang_hooks.honor_readonly && TYPE_READONLY (t1))
- || (t2 != 0 && lang_hooks.honor_readonly && TYPE_READONLY (t2)))
- return 0;
-
/* If they are the same type, they must conflict. */
if (t1 == t2
/* Likewise if both are volatile. */
static tree
find_base_decl (tree t)
{
- tree d0, d1, d2;
+ tree d0, d1;
if (t == 0 || t == error_mark_node || ! POINTER_TYPE_P (TREE_TYPE (t)))
return 0;
- /* If this is a declaration, return it. */
- if (TREE_CODE_CLASS (TREE_CODE (t)) == 'd')
- return t;
+ /* If this is a declaration, return it. If T is based on a restrict
+ qualified decl, return that decl. */
+ if (DECL_P (t))
+ {
+ if (TREE_CODE (t) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (t))
+ t = DECL_GET_RESTRICT_BASE (t);
+ return t;
+ }
/* Handle general expressions. It would be nice to deal with
COMPONENT_REFs here. If we could tell that `a' and `b' were the
same, then `a->f' and `b->f' are also the same. */
switch (TREE_CODE_CLASS (TREE_CODE (t)))
{
- case '1':
+ case tcc_unary:
return find_base_decl (TREE_OPERAND (t, 0));
- case '2':
+ case tcc_binary:
/* Return 0 if found in neither or both are the same. */
d0 = find_base_decl (TREE_OPERAND (t, 0));
d1 = find_base_decl (TREE_OPERAND (t, 1));
else
return 0;
- case '3':
- d0 = find_base_decl (TREE_OPERAND (t, 0));
- d1 = find_base_decl (TREE_OPERAND (t, 1));
- d2 = find_base_decl (TREE_OPERAND (t, 2));
-
- /* Set any nonzero values from the last, then from the first. */
- if (d1 == 0) d1 = d2;
- if (d0 == 0) d0 = d1;
- if (d1 == 0) d1 = d0;
- if (d2 == 0) d2 = d1;
-
- /* At this point all are nonzero or all are zero. If all three are the
- same, return it. Otherwise, return zero. */
- return (d0 == d1 && d1 == d2) ? d0 : 0;
-
default:
return 0;
}
}
-/* Return 1 if all the nested component references handled by
- get_inner_reference in T are such that we can address the object in T. */
+/* Return true if all nested component references handled by
+ get_inner_reference in T are such that we should use the alias set
+ provided by the object at the heart of T.
-int
-can_address_p (tree t)
+ This is true for non-addressable components (which don't have their
+ own alias set), as well as components of objects in alias set zero.
+ This later point is a special case wherein we wish to override the
+ alias set used by the component, but we don't have per-FIELD_DECL
+ assignable alias sets. */
+
+bool
+component_uses_parent_alias_set (tree t)
{
- /* If we're at the end, it is vacuously addressable. */
- if (! handled_component_p (t))
- return 1;
+ while (1)
+ {
+ /* If we're at the end, it vacuously uses its own alias set. */
+ if (!handled_component_p (t))
+ return false;
- /* Bitfields are never addressable. */
- else if (TREE_CODE (t) == BIT_FIELD_REF)
- return 0;
+ switch (TREE_CODE (t))
+ {
+ case COMPONENT_REF:
+ if (DECL_NONADDRESSABLE_P (TREE_OPERAND (t, 1)))
+ return true;
+ break;
- /* Fields are addressable unless they are marked as nonaddressable or
- the containing type has alias set 0. */
- else if (TREE_CODE (t) == COMPONENT_REF
- && ! DECL_NONADDRESSABLE_P (TREE_OPERAND (t, 1))
- && get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) != 0
- && can_address_p (TREE_OPERAND (t, 0)))
- return 1;
+ case ARRAY_REF:
+ case ARRAY_RANGE_REF:
+ if (TYPE_NONALIASED_COMPONENT (TREE_TYPE (TREE_OPERAND (t, 0))))
+ return true;
+ break;
- /* Likewise for arrays. */
- else if ((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
- && ! TYPE_NONALIASED_COMPONENT (TREE_TYPE (TREE_OPERAND (t, 0)))
- && get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) != 0
- && can_address_p (TREE_OPERAND (t, 0)))
- return 1;
+ case REALPART_EXPR:
+ case IMAGPART_EXPR:
+ break;
- return 0;
+ default:
+ /* Bitfields and casts are never addressable. */
+ return true;
+ }
+
+ t = TREE_OPERAND (t, 0);
+ if (get_alias_set (TREE_TYPE (t)) == 0)
+ return true;
+ }
}
/* Return the alias set for T, which may be either a type or an
if (! TYPE_P (t))
{
tree inner = t;
- tree placeholder_ptr = 0;
/* Remove any nops, then give the language a chance to do
something with this tree before we look at it. */
STRIP_NOPS (t);
- set = (*lang_hooks.get_alias_set) (t);
+ set = lang_hooks.get_alias_set (t);
if (set != -1)
return set;
/* First see if the actual object referenced is an INDIRECT_REF from a
- restrict-qualified pointer or a "void *". Replace
- PLACEHOLDER_EXPRs. */
- while (TREE_CODE (inner) == PLACEHOLDER_EXPR
- || handled_component_p (inner))
+ restrict-qualified pointer or a "void *". */
+ while (handled_component_p (inner))
{
- if (TREE_CODE (inner) == PLACEHOLDER_EXPR)
- inner = find_placeholder (inner, &placeholder_ptr);
- else
- inner = TREE_OPERAND (inner, 0);
-
+ inner = TREE_OPERAND (inner, 0);
STRIP_NOPS (inner);
}
/* Check for accesses through restrict-qualified pointers. */
- if (TREE_CODE (inner) == INDIRECT_REF)
+ if (INDIRECT_REF_P (inner))
{
tree decl = find_base_decl (TREE_OPERAND (inner, 0));
/* If we haven't computed the actual alias set, do it now. */
if (DECL_POINTER_ALIAS_SET (decl) == -2)
{
+ tree pointed_to_type = TREE_TYPE (TREE_TYPE (decl));
+
/* No two restricted pointers can point at the same thing.
However, a restricted pointer can point at the same thing
as an unrestricted pointer, if that unrestricted pointer
alias set for the type pointed to by the type of the
decl. */
HOST_WIDE_INT pointed_to_alias_set
- = get_alias_set (TREE_TYPE (TREE_TYPE (decl)));
+ = get_alias_set (pointed_to_type);
if (pointed_to_alias_set == 0)
/* It's not legal to make a subset of alias set zero. */
- ;
+ DECL_POINTER_ALIAS_SET (decl) = 0;
+ else if (AGGREGATE_TYPE_P (pointed_to_type))
+ /* For an aggregate, we must treat the restricted
+ pointer the same as an ordinary pointer. If we
+ were to make the type pointed to by the
+ restricted pointer a subset of the pointed-to
+ type, then we would believe that other subsets
+ of the pointed-to type (such as fields of that
+ type) do not conflict with the type pointed to
+ by the restricted pointer. */
+ DECL_POINTER_ALIAS_SET (decl)
+ = pointed_to_alias_set;
else
{
DECL_POINTER_ALIAS_SET (decl) = new_alias_set ();
}
/* If we have an INDIRECT_REF via a void pointer, we don't
- know anything about what that might alias. */
- else if (TREE_CODE (TREE_TYPE (inner)) == VOID_TYPE)
+ know anything about what that might alias. Likewise if the
+ pointer is marked that way. */
+ else if (TREE_CODE (TREE_TYPE (inner)) == VOID_TYPE
+ || (TYPE_REF_CAN_ALIAS_ALL
+ (TREE_TYPE (TREE_OPERAND (inner, 0)))))
return 0;
}
/* Otherwise, pick up the outermost object that we could have a pointer
- to, processing conversion and PLACEHOLDER_EXPR as above. */
- placeholder_ptr = 0;
- while (TREE_CODE (t) == PLACEHOLDER_EXPR
- || (handled_component_p (t) && ! can_address_p (t)))
+ to, processing conversions as above. */
+ while (component_uses_parent_alias_set (t))
{
- if (TREE_CODE (t) == PLACEHOLDER_EXPR)
- t = find_placeholder (t, &placeholder_ptr);
- else
- t = TREE_OPERAND (t, 0);
-
+ t = TREE_OPERAND (t, 0);
STRIP_NOPS (t);
}
it. This is necessary for C++ anonymous unions, whose component
variables don't look like union members (boo!). */
if (TREE_CODE (t) == VAR_DECL
- && DECL_RTL_SET_P (t) && GET_CODE (DECL_RTL (t)) == MEM)
+ && DECL_RTL_SET_P (t) && MEM_P (DECL_RTL (t)))
return MEM_ALIAS_SET (DECL_RTL (t));
/* Now all we care about is the type. */
return TYPE_ALIAS_SET (t);
/* See if the language has special handling for this type. */
- set = (*lang_hooks.get_alias_set) (t);
+ set = lang_hooks.get_alias_set (t);
if (set != -1)
return set;
/* Return a brand-new alias set. */
+static GTY(()) HOST_WIDE_INT last_alias_set;
+
HOST_WIDE_INT
new_alias_set (void)
{
- static HOST_WIDE_INT last_alias_set;
-
if (flag_strict_aliasing)
{
- VARRAY_GROW (alias_sets, last_alias_set + 2);
+ if (!alias_sets)
+ VARRAY_GENERIC_PTR_INIT (alias_sets, 10, "alias sets");
+ else
+ VARRAY_GROW (alias_sets, last_alias_set + 2);
return ++last_alias_set;
}
else
It is illegal for SUPERSET to be zero; everything is implicitly a
subset of alias set zero. */
-void
+static void
record_alias_subset (HOST_WIDE_INT superset, HOST_WIDE_INT subset)
{
alias_set_entry superset_entry;
if (superset == subset)
return;
- if (superset == 0)
- abort ();
+ gcc_assert (superset);
superset_entry = get_alias_set_entry (superset);
if (superset_entry == 0)
{
/* Create an entry for the SUPERSET, so that we have a place to
attach the SUBSET. */
- superset_entry = xmalloc (sizeof (struct alias_set_entry));
+ superset_entry = ggc_alloc (sizeof (struct alias_set_entry));
superset_entry->alias_set = superset;
superset_entry->children
- = splay_tree_new (splay_tree_compare_ints, 0, 0);
+ = splay_tree_new_ggc (splay_tree_compare_ints);
superset_entry->has_zero_child = 0;
VARRAY_GENERIC_PTR (alias_sets, superset) = superset_entry;
}
case UNION_TYPE:
case QUAL_UNION_TYPE:
/* Recursively record aliases for the base classes, if there are any. */
- if (TYPE_BINFO (type) != NULL && TYPE_BINFO_BASETYPES (type) != NULL)
+ if (TYPE_BINFO (type))
{
int i;
- for (i = 0; i < TREE_VEC_LENGTH (TYPE_BINFO_BASETYPES (type)); i++)
- {
- tree binfo = TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), i);
- record_alias_subset (superset,
- get_alias_set (BINFO_TYPE (binfo)));
- }
+ tree binfo, base_binfo;
+
+ for (binfo = TYPE_BINFO (type), i = 0;
+ BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
+ record_alias_subset (superset,
+ get_alias_set (BINFO_TYPE (base_binfo)));
}
for (field = TYPE_FIELDS (type); field != 0; field = TREE_CHAIN (field))
if (TREE_CODE (field) == FIELD_DECL && ! DECL_NONADDRESSABLE_P (field))
/* Allocate an alias set for use in storing and reading from the varargs
spill area. */
+static GTY(()) HOST_WIDE_INT varargs_set = -1;
+
HOST_WIDE_INT
get_varargs_alias_set (void)
{
- static HOST_WIDE_INT set = -1;
-
- if (set == -1)
- set = new_alias_set ();
+#if 1
+ /* We now lower VA_ARG_EXPR, and there's currently no way to attach the
+ varargs alias set to an INDIRECT_REF (FIXME!), so we can't
+ consistently use the varargs alias set for loads from the varargs
+ area. So don't use it anywhere. */
+ return 0;
+#else
+ if (varargs_set == -1)
+ varargs_set = new_alias_set ();
- return set;
+ return varargs_set;
+#endif
}
/* Likewise, but used for the fixed portions of the frame, e.g., register
save areas. */
+static GTY(()) HOST_WIDE_INT frame_set = -1;
+
HOST_WIDE_INT
get_frame_alias_set (void)
{
- static HOST_WIDE_INT set = -1;
-
- if (set == -1)
- set = new_alias_set ();
+ if (frame_set == -1)
+ frame_set = new_alias_set ();
- return set;
+ return frame_set;
}
/* Inside SRC, the source of a SET, find a base address. */
The test above is not sufficient because the scheduler may move
a copy out of an arg reg past the NOTE_INSN_FUNCTION_BEGIN. */
if ((regno >= FIRST_PSEUDO_REGISTER || fixed_regs[regno])
- && regno < reg_base_value_size)
+ && regno < VARRAY_SIZE (reg_base_value))
{
/* If we're inside init_alias_analysis, use new_reg_base_value
to reduce the number of relaxation iterations. */
&& REG_N_SETS (regno) == 1)
return new_reg_base_value[regno];
- if (reg_base_value[regno])
- return reg_base_value[regno];
+ if (VARRAY_RTX (reg_base_value, regno))
+ return VARRAY_RTX (reg_base_value, regno);
}
return 0;
rtx src;
int n;
- if (GET_CODE (dest) != REG)
+ if (!REG_P (dest))
return;
regno = REGNO (dest);
- if (regno >= reg_base_value_size)
- abort ();
+ gcc_assert (regno < VARRAY_SIZE (reg_base_value));
/* If this spans multiple hard registers, then we must indicate that every
register has an unusable value. */
if (regno < FIRST_PSEUDO_REGISTER)
- n = HARD_REGNO_NREGS (regno, GET_MODE (dest));
+ n = hard_regno_nregs[regno][GET_MODE (dest)];
else
n = 1;
if (n != 1)
return;
}
- /* This is not the first set. If the new value is not related to the
- old value, forget the base value. Note that the following code is
- not detected:
- extern int x, y; int *p = &x; p += (&y-&x);
+ /* If this is not the first set of REGNO, see whether the new value
+ is related to the old one. There are two cases of interest:
+
+ (1) The register might be assigned an entirely new value
+ that has the same base term as the original set.
+
+ (2) The set might be a simple self-modification that
+ cannot change REGNO's base value.
+
+ If neither case holds, reject the original base value as invalid.
+ Note that the following situation is not detected:
+
+ extern int x, y; int *p = &x; p += (&y-&x);
+
ANSI C does not allow computing the difference of addresses
of distinct top level objects. */
- if (new_reg_base_value[regno])
+ if (new_reg_base_value[regno] != 0
+ && find_base_value (src) != new_reg_base_value[regno])
switch (GET_CODE (src))
{
case LO_SUM:
void
record_base_value (unsigned int regno, rtx val, int invariant)
{
- if (regno >= reg_base_value_size)
- return;
-
- if (invariant && alias_invariant)
+ if (invariant && alias_invariant && regno < alias_invariant_size)
alias_invariant[regno] = val;
- if (GET_CODE (val) == REG)
- {
- if (REGNO (val) < reg_base_value_size)
- reg_base_value[regno] = reg_base_value[REGNO (val)];
+ if (regno >= VARRAY_SIZE (reg_base_value))
+ VARRAY_GROW (reg_base_value, max_reg_num ());
+ if (REG_P (val))
+ {
+ VARRAY_RTX (reg_base_value, regno)
+ = REG_BASE_VALUE (val);
return;
}
-
- reg_base_value[regno] = find_base_value (val);
+ VARRAY_RTX (reg_base_value, regno)
+ = find_base_value (val);
}
/* Clear alias info for a register. This is used if an RTL transformation
{
unsigned int regno = REGNO (reg);
- if (regno < reg_known_value_size && regno >= FIRST_PSEUDO_REGISTER)
- reg_known_value[regno] = reg;
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ {
+ regno -= FIRST_PSEUDO_REGISTER;
+ if (regno < reg_known_value_size)
+ {
+ reg_known_value[regno] = reg;
+ reg_known_equiv_p[regno] = false;
+ }
+ }
}
+/* If a value is known for REGNO, return it. */
+
+rtx
+get_reg_known_value (unsigned int regno)
+{
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ {
+ regno -= FIRST_PSEUDO_REGISTER;
+ if (regno < reg_known_value_size)
+ return reg_known_value[regno];
+ }
+ return NULL;
+}
+
+/* Set it. */
+
+static void
+set_reg_known_value (unsigned int regno, rtx val)
+{
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ {
+ regno -= FIRST_PSEUDO_REGISTER;
+ if (regno < reg_known_value_size)
+ reg_known_value[regno] = val;
+ }
+}
+
+/* Similarly for reg_known_equiv_p. */
+
+bool
+get_reg_known_equiv_p (unsigned int regno)
+{
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ {
+ regno -= FIRST_PSEUDO_REGISTER;
+ if (regno < reg_known_value_size)
+ return reg_known_equiv_p[regno];
+ }
+ return false;
+}
+
+static void
+set_reg_known_equiv_p (unsigned int regno, bool val)
+{
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ {
+ regno -= FIRST_PSEUDO_REGISTER;
+ if (regno < reg_known_value_size)
+ reg_known_equiv_p[regno] = val;
+ }
+}
+
+
/* Returns a canonical version of X, from the point of view alias
analysis. (For example, if X is a MEM whose address is a register,
and the register has a known value (say a SYMBOL_REF), then a MEM
canon_rtx (rtx x)
{
/* Recursively look for equivalences. */
- if (GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER
- && REGNO (x) < reg_known_value_size)
- return reg_known_value[REGNO (x)] == x
- ? x : canon_rtx (reg_known_value[REGNO (x)]);
- else if (GET_CODE (x) == PLUS)
+ if (REG_P (x) && REGNO (x) >= FIRST_PSEUDO_REGISTER)
+ {
+ rtx t = get_reg_known_value (REGNO (x));
+ if (t == x)
+ return x;
+ if (t)
+ return canon_rtx (t);
+ }
+
+ if (GET_CODE (x) == PLUS)
{
rtx x0 = canon_rtx (XEXP (x, 0));
rtx x1 = canon_rtx (XEXP (x, 1));
the loop optimizer. Note we want to leave the original
MEM alone, but need to return the canonicalized MEM with
all the flags with their original values. */
- else if (GET_CODE (x) == MEM)
+ else if (MEM_P (x))
x = replace_equiv_address_nv (x, canon_rtx (XEXP (x, 0)));
return x;
/* Some RTL can be compared without a recursive examination. */
switch (code)
{
- case VALUE:
- return CSELIB_VAL_PTR (x) == CSELIB_VAL_PTR (y);
-
case REG:
return REGNO (x) == REGNO (y);
case SYMBOL_REF:
return XSTR (x, 0) == XSTR (y, 0);
+ case VALUE:
case CONST_INT:
case CONST_DOUBLE:
/* There's no need to compare the contents of CONST_DOUBLEs or
comparison for these nodes. */
return 0;
- case ADDRESSOF:
- return (XINT (x, 1) == XINT (y, 1)
- && rtx_equal_for_memref_p (XEXP (x, 0),
- XEXP (y, 0)));
-
default:
break;
}
&& rtx_equal_for_memref_p (XEXP (x, 1), XEXP (y, 0))));
/* For commutative operations, the RTX match if the operand match in any
order. Also handle the simple binary and unary cases without a loop. */
- if (code == EQ || code == NE || GET_RTX_CLASS (code) == 'c')
+ if (COMMUTATIVE_P (x))
{
rtx xop0 = canon_rtx (XEXP (x, 0));
rtx yop0 = canon_rtx (XEXP (y, 0));
|| (rtx_equal_for_memref_p (xop0, yop1)
&& rtx_equal_for_memref_p (canon_rtx (XEXP (x, 1)), yop0)));
}
- else if (GET_RTX_CLASS (code) == '<' || GET_RTX_CLASS (code) == '2')
+ else if (NON_COMMUTATIVE_P (x))
{
return (rtx_equal_for_memref_p (canon_rtx (XEXP (x, 0)),
canon_rtx (XEXP (y, 0)))
&& rtx_equal_for_memref_p (canon_rtx (XEXP (x, 1)),
canon_rtx (XEXP (y, 1))));
}
- else if (GET_RTX_CLASS (code) == '1')
+ else if (UNARY_P (x))
return rtx_equal_for_memref_p (canon_rtx (XEXP (x, 0)),
canon_rtx (XEXP (y, 0)));
contain anything but integers and other rtx's,
except for within LABEL_REFs and SYMBOL_REFs. */
default:
- abort ();
+ gcc_unreachable ();
}
}
return 1;
code = GET_CODE (x);
if (code == SYMBOL_REF || code == LABEL_REF)
return x;
- if (GET_RTX_CLASS (code) == 'o')
+ if (OBJECT_P (x))
return 0;
fmt = GET_RTX_FORMAT (code);
case VALUE:
val = CSELIB_VAL_PTR (x);
+ if (!val)
+ return 0;
for (l = val->locs; l; l = l->next)
if ((x = find_base_term (l->loc)) != 0)
return x;
case LABEL_REF:
return x;
- case ADDRESSOF:
- return REG_BASE_VALUE (frame_pointer_rtx);
-
default:
return 0;
}
if (GET_CODE (x) != VALUE)
return x;
v = CSELIB_VAL_PTR (x);
- for (l = v->locs; l; l = l->next)
- if (CONSTANT_P (l->loc))
- return l->loc;
- for (l = v->locs; l; l = l->next)
- if (GET_CODE (l->loc) != REG && GET_CODE (l->loc) != MEM)
- return l->loc;
- if (v->locs)
- return v->locs->loc;
+ if (v)
+ {
+ for (l = v->locs; l; l = l->next)
+ if (CONSTANT_P (l->loc))
+ return l->loc;
+ for (l = v->locs; l; l = l->next)
+ if (!REG_P (l->loc) && !MEM_P (l->loc))
+ return l->loc;
+ if (v->locs)
+ return v->locs->loc;
+ }
return x;
}
where SIZE is the size in bytes of the memory reference. If ADDR
is not modified by the memory reference then ADDR is returned. */
-rtx
+static rtx
addr_side_effect_eval (rtx addr, int size, int n_refs)
{
int offset = 0;
unsigned int r_x = REGNO (x), r_y = REGNO (y);
rtx i_x, i_y; /* invariant relationships of X and Y */
- i_x = r_x >= reg_base_value_size ? 0 : alias_invariant[r_x];
- i_y = r_y >= reg_base_value_size ? 0 : alias_invariant[r_y];
+ i_x = r_x >= alias_invariant_size ? 0 : alias_invariant[r_x];
+ i_y = r_y >= alias_invariant_size ? 0 : alias_invariant[r_y];
if (i_x == 0 && i_y == 0)
break;
return memrefs_conflict_p (xsize, x, ysize, canon_rtx (XEXP (y, 0)), c);
}
- if (GET_CODE (x) == ADDRESSOF)
- {
- if (y == frame_pointer_rtx
- || GET_CODE (y) == ADDRESSOF)
- return xsize <= 0 || ysize <= 0;
- }
- if (GET_CODE (y) == ADDRESSOF)
- {
- if (x == frame_pointer_rtx)
- return xsize <= 0 || ysize <= 0;
- }
-
if (CONSTANT_P (x))
{
if (GET_CODE (x) == CONST_INT && GET_CODE (y) == CONST_INT)
aliases_everything_p (rtx mem)
{
if (GET_CODE (XEXP (mem, 0)) == AND)
- /* If the address is an AND, its very hard to know at what it is
+ /* If the address is an AND, it's very hard to know at what it is
actually pointing. */
return 1;
do
{
fieldx = TREE_OPERAND (x, 1);
- typex = DECL_FIELD_CONTEXT (fieldx);
+ typex = TYPE_MAIN_VARIANT (DECL_FIELD_CONTEXT (fieldx));
y = orig_y;
do
{
fieldy = TREE_OPERAND (y, 1);
- typey = DECL_FIELD_CONTEXT (fieldy);
+ typey = TYPE_MAIN_VARIANT (DECL_FIELD_CONTEXT (fieldy));
if (typex == typey)
goto found;
x = TREE_OPERAND (x, 0);
}
while (x && TREE_CODE (x) == COMPONENT_REF);
-
/* Never found a common type. */
return false;
ioffset = INTVAL (offset);
do
{
+ tree offset = component_ref_field_offset (x);
tree field = TREE_OPERAND (x, 1);
- if (! host_integerp (DECL_FIELD_OFFSET (field), 1))
+ if (! host_integerp (offset, 1))
return NULL_RTX;
- ioffset += (tree_low_cst (DECL_FIELD_OFFSET (field), 1)
+ ioffset += (tree_low_cst (offset, 1)
+ (tree_low_cst (DECL_FIELD_BIT_OFFSET (field), 1)
/ BITS_PER_UNIT));
/* Unless both have exprs, we can't tell anything. */
if (exprx == 0 || expry == 0)
return 0;
-
+
/* If both are field references, we may be able to determine something. */
if (TREE_CODE (exprx) == COMPONENT_REF
&& TREE_CODE (expry) == COMPONENT_REF
&& nonoverlapping_component_refs_p (exprx, expry))
return 1;
+
/* If the field reference test failed, look at the DECLs involved. */
moffsetx = MEM_OFFSET (x);
if (TREE_CODE (exprx) == COMPONENT_REF)
{
- tree t = decl_for_component_ref (exprx);
- if (! t)
- return 0;
- moffsetx = adjust_offset_for_component_ref (exprx, moffsetx);
- exprx = t;
+ if (TREE_CODE (expry) == VAR_DECL
+ && POINTER_TYPE_P (TREE_TYPE (expry)))
+ {
+ tree field = TREE_OPERAND (exprx, 1);
+ tree fieldcontext = DECL_FIELD_CONTEXT (field);
+ if (ipa_type_escape_field_does_not_clobber_p (fieldcontext,
+ TREE_TYPE (field)))
+ return 1;
+ }
+ {
+ tree t = decl_for_component_ref (exprx);
+ if (! t)
+ return 0;
+ moffsetx = adjust_offset_for_component_ref (exprx, moffsetx);
+ exprx = t;
+ }
}
- else if (TREE_CODE (exprx) == INDIRECT_REF)
+ else if (INDIRECT_REF_P (exprx))
{
exprx = TREE_OPERAND (exprx, 0);
if (flag_argument_noalias < 2
moffsety = MEM_OFFSET (y);
if (TREE_CODE (expry) == COMPONENT_REF)
{
- tree t = decl_for_component_ref (expry);
- if (! t)
- return 0;
- moffsety = adjust_offset_for_component_ref (expry, moffsety);
- expry = t;
+ if (TREE_CODE (exprx) == VAR_DECL
+ && POINTER_TYPE_P (TREE_TYPE (exprx)))
+ {
+ tree field = TREE_OPERAND (expry, 1);
+ tree fieldcontext = DECL_FIELD_CONTEXT (field);
+ if (ipa_type_escape_field_does_not_clobber_p (fieldcontext,
+ TREE_TYPE (field)))
+ return 1;
+ }
+ {
+ tree t = decl_for_component_ref (expry);
+ if (! t)
+ return 0;
+ moffsety = adjust_offset_for_component_ref (expry, moffsety);
+ expry = t;
+ }
}
- else if (TREE_CODE (expry) == INDIRECT_REF)
+ else if (INDIRECT_REF_P (expry))
{
expry = TREE_OPERAND (expry, 0);
if (flag_argument_noalias < 2
/* If either RTL is not a MEM, it must be a REG or CONCAT, meaning they
can't overlap unless they are the same because we never reuse that part
of the stack frame used for locals for spilled pseudos. */
- if ((GET_CODE (rtlx) != MEM || GET_CODE (rtly) != MEM)
+ if ((!MEM_P (rtlx) || !MEM_P (rtly))
&& ! rtx_equal_p (rtlx, rtly))
return 1;
know both are and are the same, so use that as the base. The only
we can avoid overlap is if we can deduce that they are nonoverlapping
pieces of that decl, which is very rare. */
- basex = GET_CODE (rtlx) == MEM ? XEXP (rtlx, 0) : rtlx;
+ basex = MEM_P (rtlx) ? XEXP (rtlx, 0) : rtlx;
if (GET_CODE (basex) == PLUS && GET_CODE (XEXP (basex, 1)) == CONST_INT)
offsetx = INTVAL (XEXP (basex, 1)), basex = XEXP (basex, 0);
- basey = GET_CODE (rtly) == MEM ? XEXP (rtly, 0) : rtly;
+ basey = MEM_P (rtly) ? XEXP (rtly, 0) : rtly;
if (GET_CODE (basey) == PLUS && GET_CODE (XEXP (basey, 1)) == CONST_INT)
offsety = INTVAL (XEXP (basey, 1)), basey = XEXP (basey, 0);
|| (CONSTANT_P (basey) && REG_P (basex)
&& REGNO_PTR_FRAME_P (REGNO (basex))));
- sizex = (GET_CODE (rtlx) != MEM ? (int) GET_MODE_SIZE (GET_MODE (rtlx))
+ sizex = (!MEM_P (rtlx) ? (int) GET_MODE_SIZE (GET_MODE (rtlx))
: MEM_SIZE (rtlx) ? INTVAL (MEM_SIZE (rtlx))
: -1);
- sizey = (GET_CODE (rtly) != MEM ? (int) GET_MODE_SIZE (GET_MODE (rtly))
+ sizey = (!MEM_P (rtly) ? (int) GET_MODE_SIZE (GET_MODE (rtly))
: MEM_SIZE (rtly) ? INTVAL (MEM_SIZE (rtly)) :
-1);
return 1;
if (GET_MODE (mem) == BLKmode && GET_CODE (XEXP (mem, 0)) == SCRATCH)
return 1;
+ if (MEM_ALIAS_SET (x) == ALIAS_SET_MEMORY_BARRIER
+ || MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
+ return 1;
if (DIFFERENT_ALIAS_SETS_P (x, mem))
return 0;
- /* Unchanging memory can't conflict with non-unchanging memory.
- A non-unchanging read can conflict with a non-unchanging write.
- An unchanging read can conflict with an unchanging write since
- there may be a single store to this address to initialize it.
- Note that an unchanging store can conflict with a non-unchanging read
- since we have to make conservative assumptions when we have a
- record with readonly fields and we are copying the whole thing.
- Just fall through to the code below to resolve potential conflicts.
- This won't handle all cases optimally, but the possible performance
- loss should be negligible. */
- if (RTX_UNCHANGING_P (x) && ! RTX_UNCHANGING_P (mem))
+ /* Read-only memory is by definition never modified, and therefore can't
+ conflict with anything. We don't expect to find read-only set on MEM,
+ but stupid user tricks can produce them, so don't die. */
+ if (MEM_READONLY_P (x))
return 0;
if (nonoverlapping_memrefs_p (mem, x))
return 1;
if (GET_MODE (mem) == BLKmode && GET_CODE (XEXP (mem, 0)) == SCRATCH)
return 1;
+ if (MEM_ALIAS_SET (x) == ALIAS_SET_MEMORY_BARRIER
+ || MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
+ return 1;
if (DIFFERENT_ALIAS_SETS_P (x, mem))
return 0;
- /* If X is an unchanging read, then it can't possibly conflict with any
- non-unchanging store. It may conflict with an unchanging write though,
- because there may be a single store to this address to initialize it.
- Just fall through to the code below to resolve the case where we have
- both an unchanging read and an unchanging write. This won't handle all
- cases optimally, but the possible performance loss should be
- negligible. */
- if (RTX_UNCHANGING_P (x) && ! RTX_UNCHANGING_P (mem))
+ /* Read-only memory is by definition never modified, and therefore can't
+ conflict with anything. We don't expect to find read-only set on MEM,
+ but stupid user tricks can produce them, so don't die. */
+ if (MEM_READONLY_P (x))
return 0;
if (nonoverlapping_memrefs_p (x, mem))
}
/* Returns nonzero if a write to X might alias a previous read from
- (or, if WRITEP is nonzero, a write to) MEM. If CONSTP is nonzero,
- honor the RTX_UNCHANGING_P flags on X and MEM. */
+ (or, if WRITEP is nonzero, a write to) MEM. */
static int
-write_dependence_p (rtx mem, rtx x, int writep, int constp)
+write_dependence_p (rtx mem, rtx x, int writep)
{
rtx x_addr, mem_addr;
rtx fixed_scalar;
return 1;
if (GET_MODE (mem) == BLKmode && GET_CODE (XEXP (mem, 0)) == SCRATCH)
return 1;
+ if (MEM_ALIAS_SET (x) == ALIAS_SET_MEMORY_BARRIER
+ || MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
+ return 1;
if (DIFFERENT_ALIAS_SETS_P (x, mem))
return 0;
- if (constp)
- {
- /* Unchanging memory can't conflict with non-unchanging memory. */
- if (RTX_UNCHANGING_P (x) != RTX_UNCHANGING_P (mem))
- return 0;
-
- /* If MEM is an unchanging read, then it can't possibly conflict with
- the store to X, because there is at most one store to MEM, and it
- must have occurred somewhere before MEM. */
- if (! writep && RTX_UNCHANGING_P (mem))
- return 0;
- }
+ /* A read from read-only memory can't conflict with read-write memory. */
+ if (!writep && MEM_READONLY_P (mem))
+ return 0;
if (nonoverlapping_memrefs_p (x, mem))
return 0;
int
anti_dependence (rtx mem, rtx x)
{
- return write_dependence_p (mem, x, /*writep=*/0, /*constp*/1);
+ return write_dependence_p (mem, x, /*writep=*/0);
}
/* Output dependence: X is written after store in MEM takes place. */
int
output_dependence (rtx mem, rtx x)
{
- return write_dependence_p (mem, x, /*writep=*/1, /*constp*/1);
-}
-
-/* Unchanging anti dependence: Like anti_dependence but ignores
- the UNCHANGING_RTX_P property on const variable references. */
-
-int
-unchanging_anti_dependence (rtx mem, rtx x)
-{
- return write_dependence_p (mem, x, /*writep=*/0, /*constp*/0);
-}
-\f
-/* A subroutine of nonlocal_mentioned_p, returns 1 if *LOC mentions
- something which is not local to the function and is not constant. */
-
-static int
-nonlocal_mentioned_p_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
-{
- rtx x = *loc;
- rtx base;
- int regno;
-
- if (! x)
- return 0;
-
- switch (GET_CODE (x))
- {
- case SUBREG:
- if (GET_CODE (SUBREG_REG (x)) == REG)
- {
- /* Global registers are not local. */
- if (REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER
- && global_regs[subreg_regno (x)])
- return 1;
- return 0;
- }
- break;
-
- case REG:
- regno = REGNO (x);
- /* Global registers are not local. */
- if (regno < FIRST_PSEUDO_REGISTER && global_regs[regno])
- return 1;
- return 0;
-
- case SCRATCH:
- case PC:
- case CC0:
- case CONST_INT:
- case CONST_DOUBLE:
- case CONST_VECTOR:
- case CONST:
- case LABEL_REF:
- return 0;
-
- case SYMBOL_REF:
- /* Constants in the function's constants pool are constant. */
- if (CONSTANT_POOL_ADDRESS_P (x))
- return 0;
- return 1;
-
- case CALL:
- /* Non-constant calls and recursion are not local. */
- return 1;
-
- case MEM:
- /* Be overly conservative and consider any volatile memory
- reference as not local. */
- if (MEM_VOLATILE_P (x))
- return 1;
- base = find_base_term (XEXP (x, 0));
- if (base)
- {
- /* A Pmode ADDRESS could be a reference via the structure value
- address or static chain. Such memory references are nonlocal.
-
- Thus, we have to examine the contents of the ADDRESS to find
- out if this is a local reference or not. */
- if (GET_CODE (base) == ADDRESS
- && GET_MODE (base) == Pmode
- && (XEXP (base, 0) == stack_pointer_rtx
- || XEXP (base, 0) == arg_pointer_rtx
-#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
- || XEXP (base, 0) == hard_frame_pointer_rtx
-#endif
- || XEXP (base, 0) == frame_pointer_rtx))
- return 0;
- /* Constants in the function's constant pool are constant. */
- if (GET_CODE (base) == SYMBOL_REF && CONSTANT_POOL_ADDRESS_P (base))
- return 0;
- }
- return 1;
-
- case UNSPEC_VOLATILE:
- case ASM_INPUT:
- return 1;
-
- case ASM_OPERANDS:
- if (MEM_VOLATILE_P (x))
- return 1;
-
- /* Fall through. */
-
- default:
- break;
- }
-
- return 0;
-}
-
-/* Returns nonzero if X might mention something which is not
- local to the function and is not constant. */
-
-static int
-nonlocal_mentioned_p (rtx x)
-{
- if (INSN_P (x))
- {
- if (GET_CODE (x) == CALL_INSN)
- {
- if (! CONST_OR_PURE_CALL_P (x))
- return 1;
- x = CALL_INSN_FUNCTION_USAGE (x);
- if (x == 0)
- return 0;
- }
- else
- x = PATTERN (x);
- }
-
- return for_each_rtx (&x, nonlocal_mentioned_p_1, NULL);
-}
-
-/* A subroutine of nonlocal_referenced_p, returns 1 if *LOC references
- something which is not local to the function and is not constant. */
-
-static int
-nonlocal_referenced_p_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
-{
- rtx x = *loc;
-
- if (! x)
- return 0;
-
- switch (GET_CODE (x))
- {
- case MEM:
- case REG:
- case SYMBOL_REF:
- case SUBREG:
- return nonlocal_mentioned_p (x);
-
- case CALL:
- /* Non-constant calls and recursion are not local. */
- return 1;
-
- case SET:
- if (nonlocal_mentioned_p (SET_SRC (x)))
- return 1;
-
- if (GET_CODE (SET_DEST (x)) == MEM)
- return nonlocal_mentioned_p (XEXP (SET_DEST (x), 0));
-
- /* If the destination is anything other than a CC0, PC,
- MEM, REG, or a SUBREG of a REG that occupies all of
- the REG, then X references nonlocal memory if it is
- mentioned in the destination. */
- if (GET_CODE (SET_DEST (x)) != CC0
- && GET_CODE (SET_DEST (x)) != PC
- && GET_CODE (SET_DEST (x)) != REG
- && ! (GET_CODE (SET_DEST (x)) == SUBREG
- && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG
- && (((GET_MODE_SIZE (GET_MODE (SUBREG_REG (SET_DEST (x))))
- + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
- == ((GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
- + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))))
- return nonlocal_mentioned_p (SET_DEST (x));
- return 0;
-
- case CLOBBER:
- if (GET_CODE (XEXP (x, 0)) == MEM)
- return nonlocal_mentioned_p (XEXP (XEXP (x, 0), 0));
- return 0;
-
- case USE:
- return nonlocal_mentioned_p (XEXP (x, 0));
-
- case ASM_INPUT:
- case UNSPEC_VOLATILE:
- return 1;
-
- case ASM_OPERANDS:
- if (MEM_VOLATILE_P (x))
- return 1;
-
- /* Fall through. */
-
- default:
- break;
- }
-
- return 0;
-}
-
-/* Returns nonzero if X might reference something which is not
- local to the function and is not constant. */
-
-static int
-nonlocal_referenced_p (rtx x)
-{
- if (INSN_P (x))
- {
- if (GET_CODE (x) == CALL_INSN)
- {
- if (! CONST_OR_PURE_CALL_P (x))
- return 1;
- x = CALL_INSN_FUNCTION_USAGE (x);
- if (x == 0)
- return 0;
- }
- else
- x = PATTERN (x);
- }
-
- return for_each_rtx (&x, nonlocal_referenced_p_1, NULL);
-}
-
-/* A subroutine of nonlocal_set_p, returns 1 if *LOC sets
- something which is not local to the function and is not constant. */
-
-static int
-nonlocal_set_p_1 (rtx *loc, void *data ATTRIBUTE_UNUSED)
-{
- rtx x = *loc;
-
- if (! x)
- return 0;
-
- switch (GET_CODE (x))
- {
- case CALL:
- /* Non-constant calls and recursion are not local. */
- return 1;
-
- case PRE_INC:
- case PRE_DEC:
- case POST_INC:
- case POST_DEC:
- case PRE_MODIFY:
- case POST_MODIFY:
- return nonlocal_mentioned_p (XEXP (x, 0));
-
- case SET:
- if (nonlocal_mentioned_p (SET_DEST (x)))
- return 1;
- return nonlocal_set_p (SET_SRC (x));
-
- case CLOBBER:
- return nonlocal_mentioned_p (XEXP (x, 0));
-
- case USE:
- return 0;
-
- case ASM_INPUT:
- case UNSPEC_VOLATILE:
- return 1;
-
- case ASM_OPERANDS:
- if (MEM_VOLATILE_P (x))
- return 1;
-
- /* Fall through. */
-
- default:
- break;
- }
-
- return 0;
-}
-
-/* Returns nonzero if X might set something which is not
- local to the function and is not constant. */
-
-static int
-nonlocal_set_p (rtx x)
-{
- if (INSN_P (x))
- {
- if (GET_CODE (x) == CALL_INSN)
- {
- if (! CONST_OR_PURE_CALL_P (x))
- return 1;
- x = CALL_INSN_FUNCTION_USAGE (x);
- if (x == 0)
- return 0;
- }
- else
- x = PATTERN (x);
- }
-
- return for_each_rtx (&x, nonlocal_set_p_1, NULL);
-}
-
-/* Mark the function if it is pure or constant. */
-
-void
-mark_constant_function (void)
-{
- rtx insn;
- int nonlocal_memory_referenced;
-
- if (TREE_READONLY (current_function_decl)
- || DECL_IS_PURE (current_function_decl)
- || TREE_THIS_VOLATILE (current_function_decl)
- || current_function_has_nonlocal_goto
- || !(*targetm.binds_local_p) (current_function_decl))
- return;
-
- /* A loop might not return which counts as a side effect. */
- if (mark_dfs_back_edges ())
- return;
-
- nonlocal_memory_referenced = 0;
-
- init_alias_analysis ();
-
- /* Determine if this is a constant or pure function. */
-
- for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
- {
- if (! INSN_P (insn))
- continue;
-
- if (nonlocal_set_p (insn) || global_reg_mentioned_p (insn)
- || volatile_refs_p (PATTERN (insn)))
- break;
-
- if (! nonlocal_memory_referenced)
- nonlocal_memory_referenced = nonlocal_referenced_p (insn);
- }
-
- end_alias_analysis ();
-
- /* Mark the function. */
-
- if (insn)
- ;
- else if (nonlocal_memory_referenced)
- {
- cgraph_rtl_info (current_function_decl)->pure_function = 1;
- DECL_IS_PURE (current_function_decl) = 1;
- }
- else
- {
- cgraph_rtl_info (current_function_decl)->const_function = 1;
- TREE_READONLY (current_function_decl) = 1;
- }
+ return write_dependence_p (mem, x, /*writep=*/1);
}
\f
{
int i;
-#ifndef OUTGOING_REGNO
-#define OUTGOING_REGNO(N) N
-#endif
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
/* Check whether this register can hold an incoming pointer
argument. FUNCTION_ARG_REGNO_P tests outgoing register
static_reg_base_value[HARD_FRAME_POINTER_REGNUM]
= gen_rtx_ADDRESS (Pmode, hard_frame_pointer_rtx);
#endif
-
- VARRAY_GENERIC_PTR_INIT (alias_sets, 10, "alias sets");
}
/* Set MEMORY_MODIFIED when X modifies DATA (that is assumed
static void
memory_modified_1 (rtx x, rtx pat ATTRIBUTE_UNUSED, void *data)
{
- if (GET_CODE (x) == MEM)
+ if (MEM_P (x))
{
if (anti_dependence (x, (rtx)data) || output_dependence (x, (rtx)data))
memory_modified = true;
/* Return true when INSN possibly modify memory contents of MEM
- (ie address can be modified). */
+ (i.e. address can be modified). */
bool
memory_modified_in_insn_p (rtx mem, rtx insn)
{
void
init_alias_analysis (void)
{
- int maxreg = max_reg_num ();
+ unsigned int maxreg = max_reg_num ();
int changed, pass;
int i;
unsigned int ui;
timevar_push (TV_ALIAS_ANALYSIS);
- reg_known_value_size = maxreg;
-
- reg_known_value
- = (rtx *) xcalloc ((maxreg - FIRST_PSEUDO_REGISTER), sizeof (rtx))
- - FIRST_PSEUDO_REGISTER;
- reg_known_equiv_p
- = (char*) xcalloc ((maxreg - FIRST_PSEUDO_REGISTER), sizeof (char))
- - FIRST_PSEUDO_REGISTER;
+ reg_known_value_size = maxreg - FIRST_PSEUDO_REGISTER;
+ reg_known_value = ggc_calloc (reg_known_value_size, sizeof (rtx));
+ reg_known_equiv_p = xcalloc (reg_known_value_size, sizeof (bool));
/* Overallocate reg_base_value to allow some growth during loop
optimization. Loop unrolling can create a large number of
registers. */
- reg_base_value_size = maxreg * 2;
- reg_base_value = ggc_alloc_cleared (reg_base_value_size * sizeof (rtx));
-
- new_reg_base_value = xmalloc (reg_base_value_size * sizeof (rtx));
- reg_seen = xmalloc (reg_base_value_size);
- if (! reload_completed && flag_old_unroll_loops)
+ if (old_reg_base_value)
{
- /* ??? Why are we realloc'ing if we're just going to zero it? */
- alias_invariant = xrealloc (alias_invariant,
- reg_base_value_size * sizeof (rtx));
- memset (alias_invariant, 0, reg_base_value_size * sizeof (rtx));
+ reg_base_value = old_reg_base_value;
+ /* If varray gets large zeroing cost may get important. */
+ if (VARRAY_SIZE (reg_base_value) > 256
+ && VARRAY_SIZE (reg_base_value) > 4 * maxreg)
+ VARRAY_GROW (reg_base_value, maxreg);
+ VARRAY_CLEAR (reg_base_value);
+ if (VARRAY_SIZE (reg_base_value) < maxreg)
+ VARRAY_GROW (reg_base_value, maxreg);
+ }
+ else
+ {
+ VARRAY_RTX_INIT (reg_base_value, maxreg, "reg_base_value");
}
+ new_reg_base_value = XNEWVEC (rtx, maxreg);
+ reg_seen = XNEWVEC (char, maxreg);
+
/* The basic idea is that each pass through this loop will use the
"constant" information from the previous pass to propagate alias
information through another level of assignments.
copying_arguments = true;
/* Wipe the potential alias information clean for this pass. */
- memset (new_reg_base_value, 0, reg_base_value_size * sizeof (rtx));
+ memset (new_reg_base_value, 0, maxreg * sizeof (rtx));
/* Wipe the reg_seen array clean. */
- memset (reg_seen, 0, reg_base_value_size);
+ memset (reg_seen, 0, maxreg);
/* Mark all hard registers which may contain an address.
The stack, frame and argument pointers may contain an address.
set = single_set (insn);
if (set != 0
- && GET_CODE (SET_DEST (set)) == REG
+ && REG_P (SET_DEST (set))
&& REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER)
{
unsigned int regno = REGNO (SET_DEST (set));
rtx src = SET_SRC (set);
+ rtx t;
if (REG_NOTES (insn) != 0
&& (((note = find_reg_note (insn, REG_EQUAL, 0)) != 0
|| (note = find_reg_note (insn, REG_EQUIV, NULL_RTX)) != 0)
&& GET_CODE (XEXP (note, 0)) != EXPR_LIST
&& ! rtx_varies_p (XEXP (note, 0), 1)
- && ! reg_overlap_mentioned_p (SET_DEST (set), XEXP (note, 0)))
+ && ! reg_overlap_mentioned_p (SET_DEST (set),
+ XEXP (note, 0)))
{
- reg_known_value[regno] = XEXP (note, 0);
- reg_known_equiv_p[regno] = REG_NOTE_KIND (note) == REG_EQUIV;
+ set_reg_known_value (regno, XEXP (note, 0));
+ set_reg_known_equiv_p (regno,
+ REG_NOTE_KIND (note) == REG_EQUIV);
}
else if (REG_N_SETS (regno) == 1
&& GET_CODE (src) == PLUS
- && GET_CODE (XEXP (src, 0)) == REG
- && REGNO (XEXP (src, 0)) >= FIRST_PSEUDO_REGISTER
- && (reg_known_value[REGNO (XEXP (src, 0))])
+ && REG_P (XEXP (src, 0))
+ && (t = get_reg_known_value (REGNO (XEXP (src, 0))))
&& GET_CODE (XEXP (src, 1)) == CONST_INT)
{
- rtx op0 = XEXP (src, 0);
- op0 = reg_known_value[REGNO (op0)];
- reg_known_value[regno]
- = plus_constant (op0, INTVAL (XEXP (src, 1)));
- reg_known_equiv_p[regno] = 0;
+ t = plus_constant (t, INTVAL (XEXP (src, 1)));
+ set_reg_known_value (regno, t);
+ set_reg_known_equiv_p (regno, 0);
}
else if (REG_N_SETS (regno) == 1
&& ! rtx_varies_p (src, 1))
{
- reg_known_value[regno] = src;
- reg_known_equiv_p[regno] = 0;
+ set_reg_known_value (regno, src);
+ set_reg_known_equiv_p (regno, 0);
}
}
}
- else if (GET_CODE (insn) == NOTE
+ else if (NOTE_P (insn)
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG)
copying_arguments = false;
}
/* Now propagate values from new_reg_base_value to reg_base_value. */
- for (ui = 0; ui < reg_base_value_size; ui++)
+ gcc_assert (maxreg == (unsigned int) max_reg_num());
+
+ for (ui = 0; ui < maxreg; ui++)
{
if (new_reg_base_value[ui]
- && new_reg_base_value[ui] != reg_base_value[ui]
- && ! rtx_equal_p (new_reg_base_value[ui], reg_base_value[ui]))
+ && new_reg_base_value[ui] != VARRAY_RTX (reg_base_value, ui)
+ && ! rtx_equal_p (new_reg_base_value[ui],
+ VARRAY_RTX (reg_base_value, ui)))
{
- reg_base_value[ui] = new_reg_base_value[ui];
+ VARRAY_RTX (reg_base_value, ui) = new_reg_base_value[ui];
changed = 1;
}
}
while (changed && ++pass < MAX_ALIAS_LOOP_PASSES);
/* Fill in the remaining entries. */
- for (i = FIRST_PSEUDO_REGISTER; i < maxreg; i++)
+ for (i = 0; i < (int)reg_known_value_size; i++)
if (reg_known_value[i] == 0)
- reg_known_value[i] = regno_reg_rtx[i];
+ reg_known_value[i] = regno_reg_rtx[i + FIRST_PSEUDO_REGISTER];
/* Simplify the reg_base_value array so that no register refers to
another register, except to special registers indirectly through
{
changed = 0;
pass++;
- for (ui = 0; ui < reg_base_value_size; ui++)
+ for (ui = 0; ui < maxreg; ui++)
{
- rtx base = reg_base_value[ui];
- if (base && GET_CODE (base) == REG)
+ rtx base = VARRAY_RTX (reg_base_value, ui);
+ if (base && REG_P (base))
{
unsigned int base_regno = REGNO (base);
if (base_regno == ui) /* register set from itself */
- reg_base_value[ui] = 0;
+ VARRAY_RTX (reg_base_value, ui) = 0;
else
- reg_base_value[ui] = reg_base_value[base_regno];
+ VARRAY_RTX (reg_base_value, ui)
+ = VARRAY_RTX (reg_base_value, base_regno);
changed = 1;
}
}
void
end_alias_analysis (void)
{
- free (reg_known_value + FIRST_PSEUDO_REGISTER);
+ old_reg_base_value = reg_base_value;
+ ggc_free (reg_known_value);
reg_known_value = 0;
reg_known_value_size = 0;
- free (reg_known_equiv_p + FIRST_PSEUDO_REGISTER);
+ free (reg_known_equiv_p);
reg_known_equiv_p = 0;
- reg_base_value = 0;
- reg_base_value_size = 0;
if (alias_invariant)
{
- free (alias_invariant);
+ ggc_free (alias_invariant);
alias_invariant = 0;
+ alias_invariant_size = 0;
}
}
+\f
+/* Do control and data flow analysis; write some of the results to the
+ dump file. */
+static void
+rest_of_handle_cfg (void)
+{
+ if (dump_file)
+ dump_flow_info (dump_file, dump_flags);
+ if (optimize)
+ cleanup_cfg (CLEANUP_EXPENSIVE
+ | (flag_thread_jumps ? CLEANUP_THREADING : 0));
+}
+
+struct tree_opt_pass pass_cfg =
+{
+ "cfg", /* name */
+ NULL, /* gate */
+ rest_of_handle_cfg, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_FLOW, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ TODO_dump_func, /* todo_flags_finish */
+ 'f' /* letter */
+};
+
#include "gt-alias.h"
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