diff options
Diffstat (limited to 'gcc/rtl.def')
| -rw-r--r-- | gcc/rtl.def | 89 |
1 files changed, 70 insertions, 19 deletions
diff --git a/gcc/rtl.def b/gcc/rtl.def index 5608676f205..a33f245b286 100644 --- a/gcc/rtl.def +++ b/gcc/rtl.def @@ -358,9 +358,8 @@ DEF_RTL_EXPR(ADDRESS, "address", "e", 'm') DEF_RTL_EXPR(DEFINE_CPU_UNIT, "define_cpu_unit", "sS", 'x') /* (define_query_cpu_unit string [string]) describes cpu functional - units analogously to define_cpu_unit. If we use automaton without - minimization, the reservation of such units can be queried for - automaton state. */ + units analogously to define_cpu_unit. The reservation of such + units can be queried for automaton state. */ DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", 'x') /* (exclusion_set string string) means that each CPU functional unit @@ -370,28 +369,80 @@ DEF_RTL_EXPR(DEFINE_QUERY_CPU_UNIT, "define_query_cpu_unit", "sS", 'x') for description CPU with fully pipelined floating point functional unit which can execute simultaneously only single floating point insns or only double floating point insns. All CPU functional - units in a set should belong the same automaton. */ + units in a set should belong to the same automaton. */ DEF_RTL_EXPR(EXCLUSION_SET, "exclusion_set", "ss", 'x') /* (presence_set string string) means that each CPU functional unit in - the first string can not be reserved unless at least one of units - whose names are in the second string is reserved. This is an - asymmetric relation. CPU units in the string are separated by - commas. For example, it is useful for description that slot1 is - reserved after slot0 reservation for VLIW processor. All CPU - functional units in a set should belong the same automaton. */ + the first string can not be reserved unless at least one of pattern + of units whose names are in the second string is reserved. This is + an asymmetric relation. CPU units or unit patterns in the strings + are separated by commas. Pattern is one unit name or unit names + separated by white-spaces. + + For example, it is useful for description that slot1 is reserved + after slot0 reservation for a VLIW processor. We could describe it + by the following construction + + (presence_set "slot1" "slot0") + + Or slot1 is reserved only after slot0 and unit b0 reservation. In + this case we could write + + (presence_set "slot1" "slot0 b0") + + All CPU functional units in a set should belong to the same + automaton. */ DEF_RTL_EXPR(PRESENCE_SET, "presence_set", "ss", 'x') +/* (final_presence_set string string) is analogous to `presence_set'. + The difference between them is when checking is done. When an + instruction is issued in given automaton state reflecting all + current and planned unit reservations, the automaton state is + changed. The first state is a source state, the second one is a + result state. Checking for `presence_set' is done on the source + state reservation, checking for `final_presence_set' is done on the + result reservation. This construction is useful to describe a + reservation which is actually two subsequent reservations. For + example, if we use + + (presence_set "slot1" "slot0") + + the following insn will be never issued (because slot1 requires + slot0 which is absent in the source state). + + (define_reservation "insn_and_nop" "slot0 + slot1") + + but it can be issued if we use analogous `final_presence_set'. */ +DEF_RTL_EXPR(FINAL_PRESENCE_SET, "final_presence_set", "ss", 'x') + /* (absence_set string string) means that each CPU functional unit in - the first string can not be reserved only if each unit whose name - is in the second string is not reserved. This is an asymmetric - relation (actually exclusion set is analogous to this one but it is - symmetric). CPU units in the string are separated by commas. For - example, it is useful for description that slot0 can not be - reserved after slot1 or slot2 reservation for VLIW processor. All - CPU functional units in a set should belong the same automaton. */ + the first string can be reserved only if each pattern of units + whose names are in the second string is not reserved. This is an + asymmetric relation (actually exclusion set is analogous to this + one but it is symmetric). CPU units or unit patterns in the string + are separated by commas. Pattern is one unit name or unit names + separated by white-spaces. + + For example, it is useful for description that slot0 can not be + reserved after slot1 or slot2 reservation for a VLIW processor. We + could describe it by the following construction + + (absence_set "slot2" "slot0, slot1") + + Or slot2 can not be reserved if slot0 and unit b0 are reserved or + slot1 and unit b1 are reserved . In this case we could write + + (absence_set "slot2" "slot0 b0, slot1 b1") + + All CPU functional units in a set should to belong the same + automaton. */ DEF_RTL_EXPR(ABSENCE_SET, "absence_set", "ss", 'x') +/* (final_absence_set string string) is analogous to `absence_set' but + checking is done on the result (state) reservation. See comments + for `final_presence_set'. */ +DEF_RTL_EXPR(FINAL_ABSENCE_SET, "final_absence_set", "ss", 'x') + /* (define_bypass number out_insn_names in_insn_names) names bypass with given latency (the first number) from insns given by the first string (see define_insn_reservation) into insns given by the second @@ -416,8 +467,8 @@ DEF_RTL_EXPR(DEFINE_AUTOMATON, "define_automaton", "s", 'x') automata. Currently there are the following options: o "no-minimization" which makes no minimization of automata. This - is only worth to do when we are going to query CPU functional - unit reservations in an automaton state. + is only worth to do when we are debugging the description and + need to look more accurately at reservations of states. o "time" which means printing additional time statistics about generation of automata. |