diff options
Diffstat (limited to 'gcc/targhooks.cc')
| -rw-r--r-- | gcc/targhooks.cc | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/gcc/targhooks.cc b/gcc/targhooks.cc index 8a69051..8ea8d77 100644 --- a/gcc/targhooks.cc +++ b/gcc/targhooks.cc @@ -95,6 +95,7 @@ along with GCC; see the file COPYING3. If not see #include "tree-vectorizer.h" #include "options.h" #include "case-cfn-macros.h" +#include "avoid-store-forwarding.h" bool default_legitimate_address_p (machine_mode mode ATTRIBUTE_UNUSED, @@ -2280,6 +2281,32 @@ default_class_max_nregs (reg_class_t rclass ATTRIBUTE_UNUSED, #endif } +/* The default implementation of TARGET_AVOID_STORE_FORWARDING_P. */ + +bool +default_avoid_store_forwarding_p (vec<store_fwd_info>, rtx, int total_cost, + bool) +{ + /* Use a simple cost heurstic base on param_store_forwarding_max_distance. + In general the distance should be somewhat correlated to the store + forwarding penalty; if the penalty is large then it is justified to + increase the window size. Use this to reject sequences that are clearly + unprofitable. + Skip the cost check if param_store_forwarding_max_distance is 0. */ + int max_cost = COSTS_N_INSNS (param_store_forwarding_max_distance / 2); + const bool unlimited_cost = (param_store_forwarding_max_distance == 0); + if (!unlimited_cost && total_cost > max_cost && max_cost) + { + if (dump_file) + fprintf (dump_file, "Not transformed due to cost: %d > %d.\n", + total_cost, max_cost); + + return false; + } + + return true; +} + /* Determine the debugging unwind mechanism for the target. */ enum unwind_info_type |