Hi,
Gentle ping https://gcc.gnu.org/pipermail/gcc-patches/2022-May/594699.html
BR,
Kewen
on 2022/5/13 13:29, Kewen.Lin via Gcc-patches wrote:
> Hi,
>
> PR105485 exposes that new builtin function framework doesn't handle
> unresolved overloaded builtin function well. With new builtin
> function support, we don't have builtin info for any overloaded
> rs6000_gen_builtins enum, since they are expected to be resolved to
> one specific instance. So when function rs6000_gimple_fold_builtin
> faces one unresolved overloaded builtin, the access for builtin info
> becomes out of bound and gets ICE then.
>
> We should not try to fold one unresolved overloaded builtin there
> and as the previous support we should emit one error message during
> expansion phase like "unresolved overload for builtin ...".
>
> Bootstrapped and regtested on powerpc64-linux-gnu P8 and
> powerpc64le-linux-gnu P9 and P10.
>
> Is it ok for trunk?
>
> BR,
> Kewen
> -----
> PR target/105485
>
> gcc/ChangeLog:
>
> * config/rs6000/rs6000-builtin.cc (rs6000_gimple_fold_builtin): Add
> the handling for unresolved overloaded builtin function.
> (rs6000_expand_builtin): Likewise.
>
> gcc/testsuite/ChangeLog:
>
> * g++.target/powerpc/pr105485.C: New test.
>
> ---
> gcc/config/rs6000/rs6000-builtin.cc | 13 +++++++++++++
> gcc/testsuite/g++.target/powerpc/pr105485.C | 9 +++++++++
> 2 files changed, 22 insertions(+)
> create mode 100644 gcc/testsuite/g++.target/powerpc/pr105485.C
>
> diff --git a/gcc/config/rs6000/rs6000-builtin.cc
> b/gcc/config/rs6000/rs6000-builtin.cc
> index e925ba9fad9..e102305c90c 100644
> --- a/gcc/config/rs6000/rs6000-builtin.cc
> +++ b/gcc/config/rs6000/rs6000-builtin.cc
> @@ -1294,6 +1294,11 @@ rs6000_gimple_fold_builtin (gimple_stmt_iterator *gsi)
> enum tree_code bcode;
> gimple *g;
>
> + /* For an unresolved overloaded builtin, return early here since there
> + is no builtin info for it and we are unable to fold it. */
> + if (fn_code > RS6000_OVLD_NONE)
> + return false;
> +
> size_t uns_fncode = (size_t) fn_code;
> enum insn_code icode = rs6000_builtin_info[uns_fncode].icode;
> const char *fn_name1 = rs6000_builtin_info[uns_fncode].bifname;
> @@ -3295,6 +3300,14 @@ rs6000_expand_builtin (tree exp, rtx target, rtx /*
> subtarget */,
> tree fndecl = TREE_OPERAND (CALL_EXPR_FN (exp), 0);
> enum rs6000_gen_builtins fcode
> = (enum rs6000_gen_builtins) DECL_MD_FUNCTION_CODE (fndecl);
> +
> + /* Emit error message if it's an unresolved overloaded builtin. */
> + if (fcode > RS6000_OVLD_NONE)
> + {
> + error ("unresolved overload for builtin %qF", fndecl);
> + return const0_rtx;
> + }
> +
> size_t uns_fcode = (size_t)fcode;
> enum insn_code icode = rs6000_builtin_info[uns_fcode].icode;
>
> diff --git a/gcc/testsuite/g++.target/powerpc/pr105485.C
> b/gcc/testsuite/g++.target/powerpc/pr105485.C
> new file mode 100644
> index 00000000000..a3b8290df8c
> --- /dev/null
> +++ b/gcc/testsuite/g++.target/powerpc/pr105485.C
> @@ -0,0 +1,9 @@
> +/* It's to verify no ICE here, ignore error/warning messages since
> + they are not test points here. */
> +/* { dg-excess-errors "pr105485" } */
> +
> +template <class> void __builtin_vec_vslv();
> +typedef __attribute__((altivec(vector__))) char T;
> +T b (T c, T d) {
> + return __builtin_vec_vslv(c, d);
> +}
