On Thu, Sep 14, 2023 at 3:25 PM Qing Zhao via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> on conflict across an abnormal edge
>
> This is a bug in tree-ssa-math-opts.cc, when applying the widening mul
> optimization, the compiler needs to check whether the operand is in a
> ABNORMAL PHI, if YES, we should avoid the transformation.
>
> bootstrapped and regression tested on both aarch64 and x86, no issue.
>
> Okay for committing?
OK.
> thanks.
>
> Qing
>
> =====
>
> PR tree-optimization/111407
>
> gcc/ChangeLog:
>
> * tree-ssa-math-opts.cc (convert_mult_to_widen): Avoid the transform
> when one of the operands is subject to abnormal coalescing.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/pr111407.c: New test.
> ---
> gcc/testsuite/gcc.dg/pr111407.c | 21 +++++++++++++++++++++
> gcc/tree-ssa-math-opts.cc | 8 ++++++++
> 2 files changed, 29 insertions(+)
> create mode 100644 gcc/testsuite/gcc.dg/pr111407.c
>
> diff --git a/gcc/testsuite/gcc.dg/pr111407.c b/gcc/testsuite/gcc.dg/pr111407.c
> new file mode 100644
> index 00000000000..a171074753f
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/pr111407.c
> @@ -0,0 +1,21 @@
> +/* PR tree-optimization/111407*/
> +/* { dg-do compile } */
> +/* { dg-options "-O2" } */
> +enum { SEND_TOFILE } __sigsetjmp();
> +void fclose();
> +void foldergets();
> +void sendpart_stats(int *p1, int a1, int b1) {
> + int *a = p1;
> + fclose();
> + p1 = 0;
> + long t = b1;
> + if (__sigsetjmp()) {
> + {
> + long t1 = a1;
> + a1+=1;
> + fclose(a1*(long)t1);
> + }
> + }
> + if (p1)
> + fclose();
> +}
> diff --git a/gcc/tree-ssa-math-opts.cc b/gcc/tree-ssa-math-opts.cc
> index 3db69ad5733..51c14d6bad9 100644
> --- a/gcc/tree-ssa-math-opts.cc
> +++ b/gcc/tree-ssa-math-opts.cc
> @@ -2755,6 +2755,14 @@ convert_mult_to_widen (gimple *stmt,
> gimple_stmt_iterator *gsi)
> if (!is_widening_mult_p (stmt, &type1, &rhs1, &type2, &rhs2))
> return false;
>
> + /* if any one of rhs1 and rhs2 is subject to abnormal coalescing,
> + avoid the tranform. */
> + if ((TREE_CODE (rhs1) == SSA_NAME
> + && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs1))
> + || (TREE_CODE (rhs2) == SSA_NAME
> + && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rhs2)))
> + return false;
> +
> to_mode = SCALAR_INT_TYPE_MODE (type);
> from_mode = SCALAR_INT_TYPE_MODE (type1);
> if (to_mode == from_mode)
> --
> 2.31.1
>
