+2014-10-27 Alan Lawrence <alan.lawrence@arm.com>
+
+ PR tree-optimization/61114
+ * doc/md.texi (Standard Names): Add reduc_(plus,[us](min|max))|scal
+ optabs, and note in reduc_[us](plus|min|max) to prefer the former.
+
+ * expr.c (expand_expr_real_2): Use reduc_..._scal if available, fall
+ back to old reduc_... + BIT_FIELD_REF only if not.
+
+ * optabs.c (optab_for_tree_code): for REDUC_(MAX,MIN,PLUS)_EXPR,
+ return the reduce-to-scalar (reduc_..._scal) optab.
+ (scalar_reduc_to_vector): New.
+
+ * optabs.def (reduc_smax_scal_optab, reduc_smin_scal_optab,
+ reduc_plus_scal_optab, reduc_umax_scal_optab, reduc_umin_scal_optab):
+ New.
+
+ * optabs.h (scalar_reduc_to_vector): Declare.
+
+ * tree-vect-loop.c (vectorizable_reduction): Look for optabs reducing
+ to either scalar or vector.
+
2014-10-27 Alan Lawrence <alan.lawrence@arm.com>
PR tree-optimization/61114
@cindex @code{reduc_smax_@var{m}} instruction pattern
@item @samp{reduc_smin_@var{m}}, @samp{reduc_smax_@var{m}}
Find the signed minimum/maximum of the elements of a vector. The vector is
-operand 1, and the scalar result is stored in the least significant bits of
+operand 1, and the result is stored in the least significant bits of
operand 0 (also a vector). The output and input vector should have the same
-modes.
+modes. These are legacy optabs, and platforms should prefer to implement
+@samp{reduc_smin_scal_@var{m}} and @samp{reduc_smax_scal_@var{m}}.
@cindex @code{reduc_umin_@var{m}} instruction pattern
@cindex @code{reduc_umax_@var{m}} instruction pattern
@item @samp{reduc_umin_@var{m}}, @samp{reduc_umax_@var{m}}
Find the unsigned minimum/maximum of the elements of a vector. The vector is
-operand 1, and the scalar result is stored in the least significant bits of
+operand 1, and the result is stored in the least significant bits of
operand 0 (also a vector). The output and input vector should have the same
-modes.
+modes. These are legacy optabs, and platforms should prefer to implement
+@samp{reduc_umin_scal_@var{m}} and @samp{reduc_umax_scal_@var{m}}.
@cindex @code{reduc_splus_@var{m}} instruction pattern
-@item @samp{reduc_splus_@var{m}}
-Compute the sum of the signed elements of a vector. The vector is operand 1,
-and the scalar result is stored in the least significant bits of operand 0
-(also a vector). The output and input vector should have the same modes.
-
@cindex @code{reduc_uplus_@var{m}} instruction pattern
-@item @samp{reduc_uplus_@var{m}}
-Compute the sum of the unsigned elements of a vector. The vector is operand 1,
-and the scalar result is stored in the least significant bits of operand 0
+@item @samp{reduc_splus_@var{m}}, @samp{reduc_uplus_@var{m}}
+Compute the sum of the signed/unsigned elements of a vector. The vector is
+operand 1, and the result is stored in the least significant bits of operand 0
(also a vector). The output and input vector should have the same modes.
+These are legacy optabs, and platforms should prefer to implement
+@samp{reduc_plus_scal_@var{m}}.
+
+@cindex @code{reduc_smin_scal_@var{m}} instruction pattern
+@cindex @code{reduc_smax_scal_@var{m}} instruction pattern
+@item @samp{reduc_smin_scal_@var{m}}, @samp{reduc_smax_scal_@var{m}}
+Find the signed minimum/maximum of the elements of a vector. The vector is
+operand 1, and operand 0 is the scalar result, with mode equal to the mode of
+the elements of the input vector.
+
+@cindex @code{reduc_umin_scal_@var{m}} instruction pattern
+@cindex @code{reduc_umax_scal_@var{m}} instruction pattern
+@item @samp{reduc_umin_scal_@var{m}}, @samp{reduc_umax_scal_@var{m}}
+Find the unsigned minimum/maximum of the elements of a vector. The vector is
+operand 1, and operand 0 is the scalar result, with mode equal to the mode of
+the elements of the input vector.
+
+@cindex @code{reduc_plus_scal_@var{m}} instruction pattern
+@item @samp{reduc_plus_scal_@var{m}}
+Compute the sum of the elements of a vector. The vector is operand 1, and
+operand 0 is the scalar result, with mode equal to the mode of the elements of
+the input vector.
@cindex @code{sdot_prod@var{m}} instruction pattern
@item @samp{sdot_prod@var{m}}
op0 = expand_normal (treeop0);
this_optab = optab_for_tree_code (code, type, optab_default);
enum machine_mode vec_mode = TYPE_MODE (TREE_TYPE (treeop0));
+
+ if (optab_handler (this_optab, vec_mode) != CODE_FOR_nothing)
+ {
+ struct expand_operand ops[2];
+ enum insn_code icode = optab_handler (this_optab, vec_mode);
+
+ create_output_operand (&ops[0], target, mode);
+ create_input_operand (&ops[1], op0, vec_mode);
+ if (maybe_expand_insn (icode, 2, ops))
+ {
+ target = ops[0].value;
+ if (GET_MODE (target) != mode)
+ return gen_lowpart (tmode, target);
+ return target;
+ }
+ }
+ /* Fall back to optab with vector result, and then extract scalar. */
+ this_optab = scalar_reduc_to_vector (this_optab, type);
temp = expand_unop (vec_mode, this_optab, op0, NULL_RTX, unsignedp);
gcc_assert (temp);
/* The tree code produces a scalar result, but (somewhat by convention)
return fma_optab;
case REDUC_MAX_EXPR:
- return TYPE_UNSIGNED (type) ? reduc_umax_optab : reduc_smax_optab;
+ return TYPE_UNSIGNED (type)
+ ? reduc_umax_scal_optab : reduc_smax_scal_optab;
case REDUC_MIN_EXPR:
- return TYPE_UNSIGNED (type) ? reduc_umin_optab : reduc_smin_optab;
+ return TYPE_UNSIGNED (type)
+ ? reduc_umin_scal_optab : reduc_smin_scal_optab;
case REDUC_PLUS_EXPR:
- return TYPE_UNSIGNED (type) ? reduc_uplus_optab : reduc_splus_optab;
+ return reduc_plus_scal_optab;
case VEC_LSHIFT_EXPR:
return vec_shl_optab;
return unknown_optab;
}
}
-\f
+
+/* Given optab UNOPTAB that reduces a vector to a scalar, find instead the old
+ optab that produces a vector with the reduction result in one element,
+ for a tree with type TYPE. */
+
+optab
+scalar_reduc_to_vector (optab unoptab, const_tree type)
+{
+ switch (unoptab)
+ {
+ case reduc_plus_scal_optab:
+ return TYPE_UNSIGNED (type) ? reduc_uplus_optab : reduc_splus_optab;
+
+ case reduc_smin_scal_optab: return reduc_smin_optab;
+ case reduc_umin_scal_optab: return reduc_umin_optab;
+ case reduc_smax_scal_optab: return reduc_smax_optab;
+ case reduc_umax_scal_optab: return reduc_umax_optab;
+ default: return unknown_optab;
+ }
+}
/* Expand vector widening operations.
OPTAB_D (sincos_optab, "sincos$a3")
OPTAB_D (tan_optab, "tan$a2")
+/* Vector reduction to a scalar. */
+OPTAB_D (reduc_smax_scal_optab, "reduc_smax_scal_$a")
+OPTAB_D (reduc_smin_scal_optab, "reduc_smin_scal_$a")
+OPTAB_D (reduc_plus_scal_optab, "reduc_plus_scal_$a")
+OPTAB_D (reduc_umax_scal_optab, "reduc_umax_scal_$a")
+OPTAB_D (reduc_umin_scal_optab, "reduc_umin_scal_$a")
+/* (Old) Vector reduction, returning a vector with the result in one lane. */
OPTAB_D (reduc_smax_optab, "reduc_smax_$a")
OPTAB_D (reduc_smin_optab, "reduc_smin_$a")
OPTAB_D (reduc_splus_optab, "reduc_splus_$a")
OPTAB_D (reduc_umax_optab, "reduc_umax_$a")
OPTAB_D (reduc_umin_optab, "reduc_umin_$a")
OPTAB_D (reduc_uplus_optab, "reduc_uplus_$a")
+
OPTAB_D (sdot_prod_optab, "sdot_prod$I$a")
OPTAB_D (ssum_widen_optab, "widen_ssum$I$a3")
OPTAB_D (udot_prod_optab, "udot_prod$I$a")
vector shifts and rotates */
extern optab optab_for_tree_code (enum tree_code, const_tree, enum optab_subtype);
+/* Given an optab that reduces a vector to a scalar, find instead the old
+ optab that produces a vector with the reduction result in one element,
+ for a tree with the specified type. */
+extern optab scalar_reduc_to_vector (optab, const_tree type);
+
/* The various uses that a comparison can have; used by can_compare_p:
jumps, conditional moves, store flag operations. */
enum can_compare_purpose
epilog_reduc_code = ERROR_MARK;
}
-
- if (reduc_optab
- && optab_handler (reduc_optab, vec_mode) == CODE_FOR_nothing)
+ else if (optab_handler (reduc_optab, vec_mode) == CODE_FOR_nothing)
{
- if (dump_enabled_p ())
- dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
- "reduc op not supported by target.\n");
+ optab = scalar_reduc_to_vector (reduc_optab, vectype_out);
+ if (optab_handler (optab, vec_mode) == CODE_FOR_nothing)
+ {
+ if (dump_enabled_p ())
+ dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
+ "reduc op not supported by target.\n");
- epilog_reduc_code = ERROR_MARK;
+ epilog_reduc_code = ERROR_MARK;
+ }
}
}
else