* gcc-interface/ada-tree.h (DECL_RESTRICTED_ALIASING_P): New flag.
* gcc-interface/decl.c (gnat_to_gnu_param): For parameters passed by
reference but whose type isn't by-ref and whose mechanism hasn't been
forced to by-ref, set the DECL_RESTRICTED_ALIASING_P flag directly on
them instead of changing their type.
* gcc-interface/trans.c (scan_rhs_r): New helper function.
(independent_iterations_p): New predicate.
(Loop_Statement_to_gnu): For a loop with an iteration scheme, set an
ivdep pragma if the iterations are independent.
From-SVN: r228377
+2015-10-02 Eric Botcazou <ebotcazou@adacore.com>
+
+ * gcc-interface/ada-tree.h (DECL_RESTRICTED_ALIASING_P): New flag.
+ * gcc-interface/decl.c (gnat_to_gnu_param): For parameters passed by
+ reference but whose type isn't by-ref and whose mechanism hasn't been
+ forced to by-ref, set the DECL_RESTRICTED_ALIASING_P flag directly on
+ them instead of changing their type.
+ * gcc-interface/trans.c (scan_rhs_r): New helper function.
+ (independent_iterations_p): New predicate.
+ (Loop_Statement_to_gnu): For a loop with an iteration scheme, set an
+ ivdep pragma if the iterations are independent.
+
2015-10-02 Eric Botcazou <ebotcazou@adacore.com>
* gcc-interface/trans.c (find_loop_for): Use FOR_EACH_VEC_ELT_REVERSE.
in the main unit, i.e. the full declaration is available. */
#define DECL_TAFT_TYPE_P(NODE) DECL_LANG_FLAG_0 (TYPE_DECL_CHECK (NODE))
+/* Nonzero in a PARM_DECL passed by reference but for which only a restricted
+ form of aliasing is allowed. The first restriction comes explicitly from
+ the RM 6.2(12) clause: there is no read-after-write dependency between a
+ store based on such a PARM_DECL and a load not based on this PARM_DECL,
+ so stores based on such PARM_DECLs can be sunk past all loads based on
+ a distinct object. The second restriction can be inferred from the same
+ clause: there is no write-after-write dependency between a store based
+ on such a PARM_DECL and a store based on a distinct such PARM_DECL, as
+ the compiler would be allowed to pass the parameters by copy and the
+ order of assignment to actual parameters after a call is arbitrary as
+ per the RM 6.4.1(17) clause, so stores based on distinct such PARM_DECLs
+ can be swapped. */
+#define DECL_RESTRICTED_ALIASING_P(NODE) \
+ DECL_LANG_FLAG_0 (PARM_DECL_CHECK (NODE))
+
/* Nonzero in a DECL if it is always used by reference, i.e. an INDIRECT_REF
is needed to access the object. */
#define DECL_BY_REF_P(NODE) DECL_LANG_FLAG_1 (NODE)
bool ro_param = in_param && !Address_Taken (gnat_param);
bool by_return = false, by_component_ptr = false;
bool by_ref = false;
+ bool restricted_aliasing_p = false;
tree gnu_param;
/* Copy-return is used only for the first parameter of a valued procedure.
|| (!foreign
&& default_pass_by_ref (gnu_param_type)))))
{
+ gnu_param_type = build_reference_type (gnu_param_type);
/* We take advantage of 6.2(12) by considering that references built for
parameters whose type isn't by-ref and for which the mechanism hasn't
- been forced to by-ref are restrict-qualified in the C sense. */
- bool restrict_p
+ been forced to by-ref allow only a restricted form of aliasing. */
+ restricted_aliasing_p
= !TYPE_IS_BY_REFERENCE_P (gnu_param_type) && mech != By_Reference;
- gnu_param_type = build_reference_type (gnu_param_type);
- if (restrict_p)
- gnu_param_type
- = change_qualified_type (gnu_param_type, TYPE_QUAL_RESTRICT);
by_ref = true;
}
DECL_POINTS_TO_READONLY_P (gnu_param)
= (ro_param && (by_ref || by_component_ptr));
DECL_CAN_NEVER_BE_NULL_P (gnu_param) = Can_Never_Be_Null (gnat_param);
+ DECL_RESTRICTED_ALIASING_P (gnu_param) = restricted_aliasing_p;
/* If no Mechanism was specified, indicate what we're using, then
back-annotate it. */
return tree_int_cst_lt (val1, val2);
}
+/* Helper function for walk_tree, used by independent_iterations_p below. */
+
+static tree
+scan_rhs_r (tree *tp, int *walk_subtrees, void *data)
+{
+ bitmap *params = (bitmap *)data;
+ tree t = *tp;
+
+ /* No need to walk into types or decls. */
+ if (IS_TYPE_OR_DECL_P (t))
+ *walk_subtrees = 0;
+
+ if (TREE_CODE (t) == PARM_DECL && bitmap_bit_p (*params, DECL_UID (t)))
+ return t;
+
+ return NULL_TREE;
+}
+
+/* Return true if STMT_LIST generates independent iterations in a loop. */
+
+static bool
+independent_iterations_p (tree stmt_list)
+{
+ tree_stmt_iterator tsi;
+ bitmap params = BITMAP_GGC_ALLOC();
+ auto_vec<tree> rhs;
+ tree iter;
+ int i;
+
+ if (TREE_CODE (stmt_list) == BIND_EXPR)
+ stmt_list = BIND_EXPR_BODY (stmt_list);
+
+ /* Scan the list and return false on anything that is not either a check
+ or an assignment to a parameter with restricted aliasing. */
+ for (tsi = tsi_start (stmt_list); !tsi_end_p (tsi); tsi_next (&tsi))
+ {
+ tree stmt = tsi_stmt (tsi);
+
+ switch (TREE_CODE (stmt))
+ {
+ case COND_EXPR:
+ {
+ if (COND_EXPR_ELSE (stmt))
+ return false;
+ if (TREE_CODE (COND_EXPR_THEN (stmt)) != CALL_EXPR)
+ return false;
+ tree func = get_callee_fndecl (COND_EXPR_THEN (stmt));
+ if (!(func && TREE_THIS_VOLATILE (func)))
+ return false;
+ break;
+ }
+
+ case MODIFY_EXPR:
+ {
+ tree lhs = TREE_OPERAND (stmt, 0);
+ while (handled_component_p (lhs))
+ lhs = TREE_OPERAND (lhs, 0);
+ if (TREE_CODE (lhs) != INDIRECT_REF)
+ return false;
+ lhs = TREE_OPERAND (lhs, 0);
+ if (!(TREE_CODE (lhs) == PARM_DECL
+ && DECL_RESTRICTED_ALIASING_P (lhs)))
+ return false;
+ bitmap_set_bit (params, DECL_UID (lhs));
+ rhs.safe_push (TREE_OPERAND (stmt, 1));
+ break;
+ }
+
+ default:
+ return false;
+ }
+ }
+
+ /* At this point we know that the list contains only statements that will
+ modify parameters with restricted aliasing. Check that the statements
+ don't at the time read from these parameters. */
+ FOR_EACH_VEC_ELT (rhs, i, iter)
+ if (walk_tree_without_duplicates (&iter, scan_rhs_r, ¶ms))
+ return false;
+
+ return true;
+}
+
/* Subroutine of gnat_to_gnu to translate gnat_node, an N_Loop_Statement,
to a GCC tree, which is returned. */
add_stmt_with_node_force (rci->invariant_cond, gnat_node);
}
+ /* Second, if loop vectorization is enabled and the iterations of the
+ loop can easily be proved as independent, mark the loop. */
+ if (optimize
+ && flag_tree_loop_vectorize
+ && independent_iterations_p (LOOP_STMT_BODY (gnu_loop_stmt)))
+ LOOP_STMT_IVDEP (gnu_loop_stmt) = 1;
+
add_stmt (gnu_loop_stmt);
gnat_poplevel ();
gnu_loop_stmt = end_stmt_group ();
+2015-10-02 Eric Botcazou <ebotcazou@adacore.com>
+
+ * gnat.dg/vect15.ad[sb]: New test.
+ * gnat.dg/vect16.ad[sb]: Likewise.
+ * gnat.dg/vect17.ad[sb]: Likewise.
+ * gnat.dg/vect18.ad[sb]: Likewise.
+
2015-10-02 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
PR rtl-optimization/67786
--- /dev/null
+-- { dg-do compile { target i?86-*-* x86_64-*-* } }
+-- { dg-options "-O3 -msse2 -fdump-tree-vect-details" }
+
+package body Vect15 is
+
+ procedure Add (X, Y : Sarray; R : out Sarray) is
+ begin
+ for I in Sarray'Range loop
+ R(I) := X(I) + Y(I);
+ end loop;
+ end;
+
+end Vect15;
+
+-- { dg-final { scan-tree-dump-not "possible aliasing" "vect" } }
--- /dev/null
+package Vect15 is
+
+ type Sarray is array (1 .. 4) of Long_Float;
+ for Sarray'Alignment use 16;
+
+ procedure Add (X, Y : Sarray; R : out Sarray);
+
+end Vect15;
--- /dev/null
+-- { dg-do compile { target i?86-*-* x86_64-*-* } }
+-- { dg-options "-O3 -msse2 -fdump-tree-vect-details" }
+
+package body Vect16 is
+
+ procedure Add_Sub (X, Y : Sarray; R,S : out Sarray) is
+ begin
+ for I in Sarray'Range loop
+ R(I) := X(I) + Y(I);
+ S(I) := X(I) - Y(I);
+ end loop;
+ end;
+
+end Vect16;
+
+-- { dg-final { scan-tree-dump-not "possible aliasing" "vect" } }
--- /dev/null
+package Vect16 is
+
+ type Sarray is array (1 .. 4) of Long_Float;
+ for Sarray'Alignment use 16;
+
+ procedure Add_Sub (X, Y : Sarray; R,S : out Sarray);
+
+end Vect16;
--- /dev/null
+-- { dg-do compile { target i?86-*-* x86_64-*-* } }
+-- { dg-options "-O3 -msse2 -fdump-tree-vect-details" }
+
+package body Vect17 is
+
+ procedure Add (X, Y : aliased Sarray; R : aliased out Sarray) is
+ begin
+ for I in Sarray'Range loop
+ R(I) := X(I) + Y(I);
+ end loop;
+ end;
+
+end Vect17;
+
+-- { dg-final { scan-tree-dump "possible aliasing" "vect" } }
--- /dev/null
+package Vect17 is
+
+ type Sarray is array (1 .. 4) of Long_Float;
+ for Sarray'Alignment use 16;
+
+ procedure Add (X, Y : aliased Sarray; R : aliased out Sarray);
+
+end Vect17;
--- /dev/null
+-- { dg-do compile { target i?86-*-* x86_64-*-* } }
+-- { dg-options "-O3 -msse2 -fdump-tree-vect-details" }
+
+package body Vect18 is
+
+ procedure Comp (X, Y : Sarray; R : in out Sarray) is
+ Tmp : Long_Float := R(4);
+ begin
+ for I in 1 .. 3 loop
+ R(I+1) := R(I) + X(I) + Y(I);
+ end loop;
+ R(1) := Tmp + X(4) + Y(4);
+ end;
+
+end Vect18;
+
+-- { dg-final { scan-tree-dump "bad data dependence" "vect" } }
--- /dev/null
+package Vect18 is
+
+ type Sarray is array (1 .. 4) of Long_Float;
+ for Sarray'Alignment use 16;
+
+ procedure Comp (X, Y : Sarray; R : in out Sarray);
+
+end Vect18;
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