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);
>> +}
