On Mon, Oct 26, 2015 at 11:08 AM, Richard Sandiford
<richard.sandif...@arm.com> wrote:
> Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.
> OK to install?
Ok.
Thanks,
Richard.
> Thanks,
> Richard
>
>
> gcc/
> * builtins.c (fold_builtin_load_exponent): Rename to...
> (fold_const_builtin_load_exponent): ...this and only handle
> constant arguments.
> (fold_builtin_2): Update accordingly.
> * match.pd: Add rules previously handled by
> fold_builtin_load_exponent.
>
> gcc/testsuite/
> * gcc.dg/torture/builtin-ldexp-1.c: Skip at -O9,
>
> diff --git a/gcc/builtins.c b/gcc/builtins.c
> index 260b66d..248c009 100644
> --- a/gcc/builtins.c
> +++ b/gcc/builtins.c
> @@ -8060,20 +8060,11 @@ fold_builtin_frexp (location_t loc, tree arg0, tree
> arg1, tree rettype)
> check the mode of the TYPE parameter in certain cases. */
>
> static tree
> -fold_builtin_load_exponent (location_t loc, tree arg0, tree arg1,
> - tree type, bool ldexp)
> +fold_const_builtin_load_exponent (tree arg0, tree arg1,
> + tree type, bool ldexp)
> {
> if (validate_arg (arg0, REAL_TYPE) && validate_arg (arg1, INTEGER_TYPE))
> {
> - STRIP_NOPS (arg0);
> - STRIP_NOPS (arg1);
> -
> - /* If arg0 is 0, Inf or NaN, or if arg1 is 0, then return arg0. */
> - if (real_zerop (arg0) || integer_zerop (arg1)
> - || (TREE_CODE (arg0) == REAL_CST
> - && !real_isfinite (&TREE_REAL_CST (arg0))))
> - return omit_one_operand_loc (loc, type, arg0, arg1);
> -
> /* If both arguments are constant, then try to evaluate it. */
> if ((ldexp || REAL_MODE_FORMAT (TYPE_MODE (type))->b == 2)
> && TREE_CODE (arg0) == REAL_CST && !TREE_OVERFLOW (arg0)
> @@ -9126,11 +9117,12 @@ fold_builtin_2 (location_t loc, tree fndecl, tree
> arg0, tree arg1)
> break;
>
> CASE_FLT_FN (BUILT_IN_LDEXP):
> - return fold_builtin_load_exponent (loc, arg0, arg1, type,
> /*ldexp=*/true);
> + return fold_const_builtin_load_exponent (arg0, arg1, type,
> + /*ldexp=*/true);
> CASE_FLT_FN (BUILT_IN_SCALBN):
> CASE_FLT_FN (BUILT_IN_SCALBLN):
> - return fold_builtin_load_exponent (loc, arg0, arg1,
> - type, /*ldexp=*/false);
> + return fold_const_builtin_load_exponent (arg0, arg1, type,
> + /*ldexp=*/false);
>
> CASE_FLT_FN (BUILT_IN_FREXP):
> return fold_builtin_frexp (loc, arg0, arg1, type);
> diff --git a/gcc/match.pd b/gcc/match.pd
> index f2e7d64..b15f42f 100644
> --- a/gcc/match.pd
> +++ b/gcc/match.pd
> @@ -105,6 +105,9 @@ DEFINE_MATH_FN (NEARBYINT)
> DEFINE_MATH_FN (SIGNBIT)
> DEFINE_MATH_FN (FMIN)
> DEFINE_MATH_FN (FMAX)
> +DEFINE_MATH_FN (LDEXP)
> +DEFINE_MATH_FN (SCALBN)
> +DEFINE_MATH_FN (SCALBLN)
>
> DEFINE_INT_AND_FLOAT_ROUND_FN (FLOOR)
> DEFINE_INT_AND_FLOAT_ROUND_FN (CEIL)
> @@ -2580,6 +2583,21 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
> (COPYSIGN @0 tree_expr_nonnegative_p@1)
> (abs @0))
>
> +(for scale (LDEXP SCALBN SCALBLN)
> + /* ldexp(0, x) -> 0. */
> + (simplify
> + (scale real_zerop@0 @1)
> + @0)
> + /* ldexp(x, 0) -> x. */
> + (simplify
> + (scale @0 integer_zerop@1)
> + @0)
> + /* ldexp(x, y) -> x if x is +-Inf or NaN. */
> + (simplify
> + (scale REAL_CST@0 @1)
> + (if (!real_isfinite (TREE_REAL_CST_PTR (@0)))
> + @0)))
> +
> /* Canonicalization of sequences of math builtins. These rules represent
> IL simplifications but are not necessarily optimizations.
>
> diff --git a/gcc/testsuite/gcc.dg/torture/builtin-ldexp-1.c
> b/gcc/testsuite/gcc.dg/torture/builtin-ldexp-1.c
> index 94560a8..6412274 100644
> --- a/gcc/testsuite/gcc.dg/torture/builtin-ldexp-1.c
> +++ b/gcc/testsuite/gcc.dg/torture/builtin-ldexp-1.c
> @@ -7,6 +7,7 @@
>
> /* { dg-do link } */
> /* { dg-options "-fno-finite-math-only" { target sh*-*-* } } */
> +/* { dg-skip-if "" { *-*-* } { "-O0" } { "" } } */
>
> extern void link_error(int);
>
>
