On Tue, 2 Aug 2011, Sebastian Pop wrote:
I think that we don't want to canonicalize build_int_cst (..., [01])
to build_{one,zero}_cst. The former is really more descriptive.
The build_{one,zero}_cst wrappers were introduced for the
fold_convert (type, integer_{one,zero}_node) idiom as fold_convert
treats those constants specially and can convert it to any
numerical type (such as a complex double). For that idiom the
build_{one,zero}_cst is more descriptive if we don't know we always
deal with an integer type (in which case we'd use build_int_cst again).
Thanks,
Richard.
> ---
> gcc/tree-ssa-loop-niter.c | 32 ++++++++++++++++----------------
> 1 files changed, 16 insertions(+), 16 deletions(-)
>
> diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
> index 4acfc67..2ee3f6e 100644
> --- a/gcc/tree-ssa-loop-niter.c
> +++ b/gcc/tree-ssa-loop-niter.c
> @@ -101,7 +101,7 @@ split_to_var_and_offset (tree expr, tree *var, mpz_t
> offset)
> break;
>
> case INTEGER_CST:
> - *var = build_int_cst_type (type, 0);
> + *var = build_zero_cst (type);
> off = tree_to_double_int (expr);
> mpz_set_double_int (offset, off, TYPE_UNSIGNED (type));
> break;
> @@ -522,7 +522,7 @@ inverse (tree x, tree mask)
> }
> else
> {
> - rslt = build_int_cst (type, 1);
> + rslt = build_one_cst (type);
> for (; ctr; ctr--)
> {
> rslt = int_const_binop (MULT_EXPR, rslt, x);
> @@ -670,7 +670,7 @@ number_of_iterations_ne (tree type, affine_iv *iv, tree
> final,
> - tree_low_cst (bits, 1)));
>
> d = fold_binary_to_constant (LSHIFT_EXPR, niter_type,
> - build_int_cst (niter_type, 1), bits);
> + build_one_cst (niter_type), bits);
> s = fold_binary_to_constant (RSHIFT_EXPR, niter_type, s, bits);
>
> if (!exit_must_be_taken)
> @@ -679,7 +679,7 @@ number_of_iterations_ne (tree type, affine_iv *iv, tree
> final,
> assumptions for divisibility of c. */
> assumption = fold_build2 (FLOOR_MOD_EXPR, niter_type, c, d);
> assumption = fold_build2 (EQ_EXPR, boolean_type_node,
> - assumption, build_int_cst (niter_type, 0));
> + assumption, build_zero_cst (niter_type));
> if (!integer_nonzerop (assumption))
> niter->assumptions = fold_build2 (TRUTH_AND_EXPR, boolean_type_node,
> niter->assumptions, assumption);
> @@ -846,7 +846,7 @@ assert_no_overflow_lt (tree type, affine_iv *iv0,
> affine_iv *iv1,
> }
> else
> diff = fold_build2 (MINUS_EXPR, niter_type, step,
> - build_int_cst (niter_type, 1));
> + build_one_cst (niter_type));
> bound = fold_build2 (MINUS_EXPR, type,
> TYPE_MAX_VALUE (type), fold_convert (type, diff));
> assumption = fold_build2 (LE_EXPR, boolean_type_node,
> @@ -867,7 +867,7 @@ assert_no_overflow_lt (tree type, affine_iv *iv0,
> affine_iv *iv1,
> }
> else
> diff = fold_build2 (MINUS_EXPR, niter_type, step,
> - build_int_cst (niter_type, 1));
> + build_one_cst (niter_type));
> bound = fold_build2 (PLUS_EXPR, type,
> TYPE_MIN_VALUE (type), fold_convert (type, diff));
> assumption = fold_build2 (GE_EXPR, boolean_type_node,
> @@ -963,7 +963,7 @@ assert_loop_rolls_lt (tree type, affine_iv *iv0,
> affine_iv *iv1,
> if (integer_nonzerop (iv0->step))
> {
> diff = fold_build2 (MINUS_EXPR, type1,
> - iv0->step, build_int_cst (type1, 1));
> + iv0->step, build_one_cst (type1));
>
> /* We need to know that iv0->base >= MIN + iv0->step - 1. Since
> 0 address never belongs to any object, we can assume this for
> @@ -985,7 +985,7 @@ assert_loop_rolls_lt (tree type, affine_iv *iv0,
> affine_iv *iv1,
> else
> {
> diff = fold_build2 (PLUS_EXPR, type1,
> - iv1->step, build_int_cst (type1, 1));
> + iv1->step, build_one_cst (type1));
>
> if (!POINTER_TYPE_P (type))
> {
> @@ -1083,7 +1083,7 @@ number_of_iterations_lt (tree type, affine_iv *iv0,
> affine_iv *iv1,
> {
> affine_iv zps;
>
> - zps.base = build_int_cst (niter_type, 0);
> + zps.base = build_zero_cst (niter_type);
> zps.step = step;
> /* number_of_iterations_lt_to_ne will add assumptions that ensure that
> zps does not overflow. */
> @@ -1102,7 +1102,7 @@ number_of_iterations_lt (tree type, affine_iv *iv0,
> affine_iv *iv1,
> assert_loop_rolls_lt (type, iv0, iv1, niter, bnds);
>
> s = fold_build2 (MINUS_EXPR, niter_type,
> - step, build_int_cst (niter_type, 1));
> + step, build_one_cst (niter_type));
> delta = fold_build2 (PLUS_EXPR, niter_type, delta, s);
> niter->niter = fold_build2 (FLOOR_DIV_EXPR, niter_type, delta, step);
>
> @@ -1167,13 +1167,13 @@ number_of_iterations_le (tree type, affine_iv *iv0,
> affine_iv *iv1,
> iv1->base = fold_build_pointer_plus_hwi (iv1->base, 1);
> else
> iv1->base = fold_build2 (PLUS_EXPR, type1, iv1->base,
> - build_int_cst (type1, 1));
> + build_one_cst (type1));
> }
> else if (POINTER_TYPE_P (type))
> iv0->base = fold_build_pointer_plus_hwi (iv0->base, -1);
> else
> iv0->base = fold_build2 (MINUS_EXPR, type1,
> - iv0->base, build_int_cst (type1, 1));
> + iv0->base, build_one_cst (type1));
>
> bounds_add (bnds, double_int_one, type1);
>
> @@ -1282,7 +1282,7 @@ number_of_iterations_cond (struct loop *loop,
> iv0->step = fold_binary_to_constant (MINUS_EXPR, type,
> iv0->step, iv1->step);
> iv0->no_overflow = false;
> - iv1->step = build_int_cst (type, 0);
> + iv1->step = build_zero_cst (type);
> iv1->no_overflow = true;
> }
>
> @@ -1305,7 +1305,7 @@ number_of_iterations_cond (struct loop *loop,
> /* If the loop exits immediately, there is nothing to do. */
> if (integer_zerop (fold_build2 (code, boolean_type_node, iv0->base,
> iv1->base)))
> {
> - niter->niter = build_int_cst (unsigned_type_for (type), 0);
> + niter->niter = build_zero_cst (unsigned_type_for (type));
> niter->max = double_int_zero;
> return true;
> }
> @@ -1946,7 +1946,7 @@ find_loop_niter (struct loop *loop, edge *exit)
> {
> /* We exit in the first iteration through this exit.
> We won't find anything better. */
> - niter = build_int_cst (unsigned_type_node, 0);
> + niter = build_zero_cst (unsigned_type_node);
> *exit = ex;
> break;
> }
> @@ -3017,7 +3017,7 @@ estimate_numbers_of_iterations_loop (struct loop *loop,
> bool use_undefined_p)
> type = TREE_TYPE (niter);
> if (TREE_CODE (niter_desc.may_be_zero) != INTEGER_CST)
> niter = build3 (COND_EXPR, type, niter_desc.may_be_zero,
> - build_int_cst (type, 0),
> + build_zero_cst (type),
> niter);
> record_estimate (loop, niter, niter_desc.max,
> last_stmt (ex->src),
>
--
Richard Guenther <rguent...@suse.de>
Novell / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer
