From 363b29a9cfbb470d6987fb395035c56bae30c64b Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Thu, 10 Jul 2025 13:30:30 +0200 Subject: [PATCH] properly compute fp/mode for scalar ops for vectorizer costing The x86 add_stmt_hook relies on the passed vectype to determine the mode and whether it is FP for a scalar operation. This is unreliable now for stmts involving patterns and in the future when there is no vector type passed for scalar operations. To be least disruptive I've kept using the vector type if it is passed. * config/i386/i386.cc (ix86_vector_costs::add_stmt_cost): Use the LHS of a scalar stmt to determine mode and whether it is FP. --- gcc/config/i386/i386.cc | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc index ad7360ec71a..313522b88e3 100644 --- a/gcc/config/i386/i386.cc +++ b/gcc/config/i386/i386.cc @@ -25798,6 +25798,14 @@ ix86_vector_costs::add_stmt_cost (int count, vect_cost_for_stmt kind, if (scalar_p) mode = TYPE_MODE (TREE_TYPE (vectype)); } + /* When we are costing a scalar stmt use the scalar stmt to get at the + type of the operation. */ + else if (scalar_p && stmt_info) + if (tree lhs = gimple_get_lhs (stmt_info->stmt)) + { + fp = FLOAT_TYPE_P (TREE_TYPE (lhs)); + mode = TYPE_MODE (TREE_TYPE (lhs)); + } if ((kind == vector_stmt || kind == scalar_stmt) && stmt_info -- 2.47.2