Richard Biener <rguent...@suse.de> writes:
> On Fri, 21 Jan 2022, Jiufu Guo wrote:
>
>> Hi,
>>
>> This patch correct the type of niter->control.base, when it is updated
>> as a PLUS expr.
>> During build PLUS expr, the result type should align with the type of
>> the operands.
>>
>> Bootstrap and regtest pass on ppc64/ppc64le and x86.
>> Is this ok for trunk?
>
> OK.
>
> Thanks,
> Richard.
Thanks! committed as r12-6834.
BR,
Jiufu
>
>> BR,
>> Jiufu
>>
>>
>> PR tree-optimization/102087
>>
>> gcc/ChangeLog:
>>
>> * tree-ssa-loop-niter.c (number_of_iterations_until_wrap):
>> Correct PLUS result type.
>>
>> gcc/testsuite/ChangeLog:
>>
>> * gcc.dg/pr102087_1.c: New test.
>>
>> ---
>> gcc/tree-ssa-loop-niter.c | 17 +++++++++++++++--
>> gcc/testsuite/gcc.dg/pr102087_1.c | 13 +++++++++++++
>> 2 files changed, 28 insertions(+), 2 deletions(-)
>> create mode 100644 gcc/testsuite/gcc.dg/pr102087_1.c
>>
>> diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
>> index b767056aeb0..21cc257c91b 100644
>> --- a/gcc/tree-ssa-loop-niter.c
>> +++ b/gcc/tree-ssa-loop-niter.c
>> @@ -1579,8 +1579,21 @@ number_of_iterations_until_wrap (class loop *loop,
>> tree type, affine_iv *iv0,
>> { IVbase - STEP, +, STEP } != bound
>> Here, biasing IVbase by 1 step makes 'bound' be the value before wrap.
>> */
>> - niter->control.base = fold_build2 (MINUS_EXPR, niter_type,
>> - niter->control.base, niter->control.step);
>> + tree base_type = TREE_TYPE (niter->control.base);
>> + if (POINTER_TYPE_P (base_type))
>> + {
>> + tree utype = unsigned_type_for (base_type);
>> + niter->control.base
>> + = fold_build2 (MINUS_EXPR, utype,
>> + fold_convert (utype, niter->control.base),
>> + fold_convert (utype, niter->control.step));
>> + niter->control.base = fold_convert (base_type, niter->control.base);
>> + }
>> + else
>> + niter->control.base
>> + = fold_build2 (MINUS_EXPR, base_type, niter->control.base,
>> + niter->control.step);
>> +
>> span = fold_build2 (MULT_EXPR, niter_type, niter->niter,
>> fold_convert (niter_type, niter->control.step));
>> niter->bound = fold_build2 (PLUS_EXPR, niter_type, span,
>> diff --git a/gcc/testsuite/gcc.dg/pr102087_1.c
>> b/gcc/testsuite/gcc.dg/pr102087_1.c
>> new file mode 100644
>> index 00000000000..ba4efe3b412
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/pr102087_1.c
>> @@ -0,0 +1,13 @@
>> +/* PR tree-optimization/102087 */
>> +/* { dg-do compile } */
>> +/* { dg-options "-O3 -fprefetch-loop-arrays -w" { target x86_64-*-*
>> powerpc*-*-* } } */
>> +
>> +char **Gif_ClipImage_gfi_0;
>> +int Gif_ClipImage_gfi_1, Gif_ClipImage_y, Gif_ClipImage_shift;
>> +void Gif_ClipImage() {
>> + Gif_ClipImage_y = Gif_ClipImage_gfi_1 - 1;
>> + for (; Gif_ClipImage_y >= Gif_ClipImage_shift; Gif_ClipImage_y++)
>> + Gif_ClipImage_gfi_0[Gif_ClipImage_shift] =
>> + Gif_ClipImage_gfi_0[Gif_ClipImage_y];
>> +}
>> +
>>
