From ad4188f8385f86cc04806fb0e26c7da1f5f655b8 Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Wed, 19 Jan 2022 13:59:21 +0100 Subject: [PATCH] tree-optimization/104114 - avoid diagnosing V1mode lowering Currently we diagnose vector lowering of V1mode operations that are not natively supported into V_C_E, scalar op plus CTOR with -Wvector-operation-performance but that's hardly useful behavior even though the way we lower things can be improved. The following disables the diagnostics for the cases the vect.exp testsuite runs into, on x86 that are vect-cond-11.c and vect-singleton_1.c. 2022-01-19 Richard Biener PR tree-optimization/104114 * tree-vect-generic.cc (expand_vector_piecewise): Do not diagnose single element vector decomposition. --- gcc/tree-vect-generic.cc | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/gcc/tree-vect-generic.cc b/gcc/tree-vect-generic.cc index 5814a71..f4fc7d1 100644 --- a/gcc/tree-vect-generic.cc +++ b/gcc/tree-vect-generic.cc @@ -317,7 +317,10 @@ expand_vector_piecewise (gimple_stmt_iterator *gsi, elem_op_func f, int i; location_t loc = gimple_location (gsi_stmt (*gsi)); - if (ret_type || !parallel_p) + if (nunits == 1) + /* Do not diagnose decomposing single element vectors. */ + ; + else if (ret_type || !parallel_p) warning_at (loc, OPT_Wvector_operation_performance, "vector operation will be expanded piecewise"); else -- 2.7.4