diff options
Diffstat (limited to 'gcc/tree-vect-loop.c')
| -rw-r--r-- | gcc/tree-vect-loop.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c index f21d995..d5e3552 100644 --- a/gcc/tree-vect-loop.c +++ b/gcc/tree-vect-loop.c @@ -462,6 +462,40 @@ vect_is_simple_iv_evolution (unsigned loop_nb, tree access_fn, tree * init, return true; } +/* Return true if PHI, described by STMT_INFO, is the inner PHI in + what we are assuming is a double reduction. For example, given + a structure like this: + + outer1: + x_1 = PHI <x_4(outer2), ...>; + ... + + inner: + x_2 = PHI <x_1(outer1), ...>; + ... + x_3 = ...; + ... + + outer2: + x_4 = PHI <x_3(inner)>; + ... + + outer loop analysis would treat x_1 as a double reduction phi and + this function would then return true for x_2. */ + +static bool +vect_inner_phi_in_double_reduction_p (stmt_vec_info stmt_info, gphi *phi) +{ + loop_vec_info loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_info); + use_operand_p use_p; + ssa_op_iter op_iter; + FOR_EACH_PHI_ARG (use_p, phi, op_iter, SSA_OP_USE) + if (stmt_vec_info def_info = loop_vinfo->lookup_def (USE_FROM_PTR (use_p))) + if (STMT_VINFO_DEF_TYPE (def_info) == vect_double_reduction_def) + return true; + return false; +} + /* Function vect_analyze_scalar_cycles_1. Examine the cross iteration def-use cycles of scalar variables @@ -522,6 +556,7 @@ vect_analyze_scalar_cycles_1 (loop_vec_info loop_vinfo, struct loop *loop) } if (!access_fn + || vect_inner_phi_in_double_reduction_p (stmt_vinfo, phi) || !vect_is_simple_iv_evolution (loop->num, access_fn, &init, &step) || (LOOP_VINFO_LOOP (loop_vinfo) != loop && TREE_CODE (step) != INTEGER_CST)) |