On Fri, 27 Nov 2020, Jakub Jelinek wrote:
> Hi!
>
> My recent match.pd change required quite a lot of code due to the separate
> need to handle INTEGER_CSTs and SSA_NAMEs, and after all, I didn't even
> handle one case there, when in x * y / y the x is INTEGER_CST and y is
> SSA_NAME.
> The following patch allows to simplify it, by allowing non-SSA_NAME argument
> to get_range_info, for INTEGER_CSTs it will return VR_RANGE with *min == *max
> equal to the constnat, and for non-INTEGER_CST/SSA_NAMEs it will just return
> VR_VARYING.
>
> This allows not to simplify just the match.pd, but some other spots too.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
OK.
Thanks,
Richard.
> 2020-11-27 Jakub Jelinek <ja...@redhat.com>
>
> * tree-ssanames.c (get_range_info): Handle INTEGER_CST by returning
> VR_RANGE with both *min and *max set to the wide_int value of the
> INTEGER_CST. Return VR_VARYING for non-SSA_NAMEs.
> * match.pd ((t * 2) / 2) -> t): Handle also @0 being INTEGER_CST.
> Simplify by calling get_range_info on everything.
> * tree-ssa-strlen.c (maybe_diag_stxncpy_trunc): Simplify by calling
> get_range_info on everything.
> * tree-scalar-evolution.c (iv_can_overflow_p): Likewise.
>
> --- gcc/tree-ssanames.c.jj 2020-11-23 17:01:52.002013364 +0100
> +++ gcc/tree-ssanames.c 2020-11-26 16:28:10.092549635 +0100
> @@ -420,21 +420,30 @@ set_range_info (tree name, const value_r
> is used to determine if MIN and MAX are valid values. */
>
> enum value_range_kind
> -get_range_info (const_tree name, wide_int *min, wide_int *max)
> +get_range_info (const_tree expr, wide_int *min, wide_int *max)
> {
> - gcc_assert (!POINTER_TYPE_P (TREE_TYPE (name)));
> + gcc_assert (!POINTER_TYPE_P (TREE_TYPE (expr)));
> gcc_assert (min && max);
> - range_info_def *ri = SSA_NAME_RANGE_INFO (name);
> + if (TREE_CODE (expr) == INTEGER_CST)
> + {
> + *min = wi::to_wide (expr);
> + *max = *min;
> + return VR_RANGE;
> + }
> + if (TREE_CODE (expr) != SSA_NAME)
> + return VR_VARYING;
> +
> + range_info_def *ri = SSA_NAME_RANGE_INFO (expr);
>
> /* Return VR_VARYING for SSA_NAMEs with NULL RANGE_INFO or SSA_NAMEs
> with integral types width > 2 * HOST_BITS_PER_WIDE_INT precision. */
> - if (!ri || (GET_MODE_PRECISION (SCALAR_INT_TYPE_MODE (TREE_TYPE (name)))
> + if (!ri || (GET_MODE_PRECISION (SCALAR_INT_TYPE_MODE (TREE_TYPE (expr)))
> > 2 * HOST_BITS_PER_WIDE_INT))
> return VR_VARYING;
>
> *min = ri->get_min ();
> *max = ri->get_max ();
> - return SSA_NAME_RANGE_TYPE (name);
> + return SSA_NAME_RANGE_TYPE (expr);
> }
>
> /* Gets range information corresponding to ssa_name NAME and stores it
> --- gcc/match.pd.jj 2020-11-26 16:23:55.037394625 +0100
> +++ gcc/match.pd 2020-11-26 16:42:11.527163758 +0100
> @@ -654,42 +654,30 @@ (define_operator_list COND_TERNARY
> (if (TYPE_OVERFLOW_UNDEFINED (type))
> @0
> #if GIMPLE
> - (if (TREE_CODE (@0) == SSA_NAME
> - && (TREE_CODE (@1) == SSA_NAME || TREE_CODE (@1) == INTEGER_CST))
> - (with
> - {
> - bool overflowed = true;
> - wide_int wmin0, wmax0;
> - if (get_range_info (@0, &wmin0, &wmax0) == VR_RANGE)
> - {
> - /* If the multiplication can't overflow/wrap around, then
> - it can be optimized too. */
> - wide_int wmin1, wmax1;
> - wi::overflow_type min_ovf, max_ovf;
> - if (TREE_CODE (@1) == INTEGER_CST)
> - {
> - wmin1 = wi::to_wide (@1);
> - wi::mul (wmin0, wmin1, TYPE_SIGN (type), &min_ovf);
> - wi::mul (wmax0, wmin1, TYPE_SIGN (type), &max_ovf);
> - if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> - overflowed = false;
> - }
> - else if (get_range_info (@1, &wmin1, &wmax1) == VR_RANGE)
> - {
> - wi::mul (wmin0, wmin1, TYPE_SIGN (type), &min_ovf);
> - wi::mul (wmax0, wmax1, TYPE_SIGN (type), &max_ovf);
> - if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> - {
> - wi::mul (wmin0, wmax1, TYPE_SIGN (type), &min_ovf);
> - wi::mul (wmax0, wmin1, TYPE_SIGN (type), &max_ovf);
> - if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> - overflowed = false;
> - }
> - }
> - }
> - }
> - (if (!overflowed)
> - @0)))
> + (with
> + {
> + bool overflowed = true;
> + wide_int wmin0, wmax0, wmin1, wmax1;
> + if (INTEGRAL_TYPE_P (type)
> + && get_range_info (@0, &wmin0, &wmax0) == VR_RANGE
> + && get_range_info (@1, &wmin1, &wmax1) == VR_RANGE)
> + {
> + /* If the multiplication can't overflow/wrap around, then
> + it can be optimized too. */
> + wi::overflow_type min_ovf, max_ovf;
> + wi::mul (wmin0, wmin1, TYPE_SIGN (type), &min_ovf);
> + wi::mul (wmax0, wmax1, TYPE_SIGN (type), &max_ovf);
> + if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> + {
> + wi::mul (wmin0, wmax1, TYPE_SIGN (type), &min_ovf);
> + wi::mul (wmax0, wmin1, TYPE_SIGN (type), &max_ovf);
> + if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
> + overflowed = false;
> + }
> + }
> + }
> + (if (!overflowed)
> + @0))
> #endif
> ))))
>
> --- gcc/tree-ssa-strlen.c.jj 2020-11-18 09:40:09.782661182 +0100
> +++ gcc/tree-ssa-strlen.c 2020-11-26 16:38:02.633940185 +0100
> @@ -3038,31 +3038,24 @@ maybe_diag_stxncpy_trunc (gimple_stmt_it
>
> wide_int cntrange[2];
>
> - if (TREE_CODE (cnt) == INTEGER_CST)
> - cntrange[0] = cntrange[1] = wi::to_wide (cnt);
> - else if (TREE_CODE (cnt) == SSA_NAME)
> + // FIXME: Use range_query instead of global ranges.
> + enum value_range_kind rng = get_range_info (cnt, cntrange, cntrange + 1);
> + if (rng == VR_RANGE)
> + ;
> + else if (rng == VR_ANTI_RANGE)
> {
> - // FIXME: Use range_query instead of global ranges.
> - enum value_range_kind rng = get_range_info (cnt, cntrange, cntrange +
> 1);
> - if (rng == VR_RANGE)
> - ;
> - else if (rng == VR_ANTI_RANGE)
> - {
> - wide_int maxobjsize = wi::to_wide (TYPE_MAX_VALUE
> (ptrdiff_type_node));
> + wide_int maxobjsize = wi::to_wide (TYPE_MAX_VALUE (ptrdiff_type_node));
>
> - if (wi::ltu_p (cntrange[1], maxobjsize))
> - {
> - cntrange[0] = cntrange[1] + 1;
> - cntrange[1] = maxobjsize;
> - }
> - else
> - {
> - cntrange[1] = cntrange[0] - 1;
> - cntrange[0] = wi::zero (TYPE_PRECISION (TREE_TYPE (cnt)));
> - }
> + if (wi::ltu_p (cntrange[1], maxobjsize))
> + {
> + cntrange[0] = cntrange[1] + 1;
> + cntrange[1] = maxobjsize;
> }
> else
> - return false;
> + {
> + cntrange[1] = cntrange[0] - 1;
> + cntrange[0] = wi::zero (TYPE_PRECISION (TREE_TYPE (cnt)));
> + }
> }
> else
> return false;
> --- gcc/tree-scalar-evolution.c.jj 2020-01-12 11:54:38.500381922 +0100
> +++ gcc/tree-scalar-evolution.c 2020-11-26 16:35:24.873699912 +0100
> @@ -3043,22 +3043,12 @@ iv_can_overflow_p (class loop *loop, tre
> if (integer_zerop (step))
> return false;
>
> - if (TREE_CODE (base) == INTEGER_CST)
> - base_min = base_max = wi::to_wide (base);
> - else if (TREE_CODE (base) == SSA_NAME
> - && INTEGRAL_TYPE_P (TREE_TYPE (base))
> - && get_range_info (base, &base_min, &base_max) == VR_RANGE)
> - ;
> - else
> + if (!INTEGRAL_TYPE_P (TREE_TYPE (base))
> + || get_range_info (base, &base_min, &base_max) != VR_RANGE)
> return true;
>
> - if (TREE_CODE (step) == INTEGER_CST)
> - step_min = step_max = wi::to_wide (step);
> - else if (TREE_CODE (step) == SSA_NAME
> - && INTEGRAL_TYPE_P (TREE_TYPE (step))
> - && get_range_info (step, &step_min, &step_max) == VR_RANGE)
> - ;
> - else
> + if (!INTEGRAL_TYPE_P (TREE_TYPE (step))
> + || get_range_info (step, &step_min, &step_max) != VR_RANGE)
> return true;
>
> if (!get_max_loop_iterations (loop, &nit))
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imend
