On 19/08/16 12:48, Matthew Wahab wrote:
> Hello,
>
> Test gcc.c-torture/execute/ieee/pr72824-2.c fails for arm targets
> because the code generated to move a vector of signed and unsigned zeros
> treats it as a vector of unsigned zeros.
>
> That is, an assignment x = { 0.f, -0.f, 0.f, -0.f } is treated as the
> assignment x = { 0.f, 0.f, 0.f, 0.f }.
>
> This is due to config/arm/arm.c/neon_valid_immediate using real_equal to
> compare the vector elements. This patch replaces the check, using
> const_vec_duplicate_p instead. It doesn't add a new test because
> pr72824-2.c is enough to check the behaviour.
>
> Tested for arm-none-linux-gnueabihf with native bootstrap and make check
> and for arm-none-eabi with cross-compiled check-gcc.
>
> 2016-08-19 Matthew Wahab <matthew.wa...@arm.com>
>
> PR target/77281
> * config/arm/arm.c (neon_valid_immediate): Delete declaration.
> Use const_vec_duplicate to check for duplicated elements.
>
> Ok for trunk?
OK.
Thanks.
R.
> Matthew
>
> 0001-ARM-Fix-a-wrong-test-for-vectors-of-the-same-constan.patch
>
>
> From 90c1c86b7a3d8bc6ac07363aea5fba8f29ef3e96 Mon Sep 17 00:00:00 2001
> From: Matthew Wahab <matthew.wa...@arm.com>
> Date: Wed, 17 Aug 2016 14:43:48 +0100
> Subject: [PATCH] [ARM] Fix a wrong test for vectors of the same constants.
>
> ---
> gcc/config/arm/arm.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
> index a6afdcc..c1d010c 100644
> --- a/gcc/config/arm/arm.c
> +++ b/gcc/config/arm/arm.c
> @@ -12471,7 +12471,6 @@ neon_valid_immediate (rtx op, machine_mode mode, int
> inverse,
> if (GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
> {
> rtx el0 = CONST_VECTOR_ELT (op, 0);
> - const REAL_VALUE_TYPE *r0;
>
> if (!vfp3_const_double_rtx (el0) && el0 != CONST0_RTX (GET_MODE (el0)))
> return -1;
> @@ -12480,14 +12479,10 @@ neon_valid_immediate (rtx op, machine_mode mode,
> int inverse,
> if (GET_MODE_INNER (mode) == HFmode)
> return -1;
>
> - r0 = CONST_DOUBLE_REAL_VALUE (el0);
> -
> - for (i = 1; i < n_elts; i++)
> - {
> - rtx elt = CONST_VECTOR_ELT (op, i);
> - if (!real_equal (r0, CONST_DOUBLE_REAL_VALUE (elt)))
> - return -1;
> - }
> + /* All elements in the vector must be the same. Note that 0.0 and -0.0
> + are distinct in this context. */
> + if (!const_vec_duplicate_p (op))
> + return -1;
>
> if (modconst)
> *modconst = CONST_VECTOR_ELT (op, 0);
>
