8204084: Remove the G1RSBarrierRegionFilter develop flag

Reviewed-by: sjohanss, shade

src/hotspot/cpu/ppc/gc/g1/g1BarrierSetAssembler_ppc.cpp

@@ -214,11 +214,9 @@ void G1BarrierSetAssembler::g1_write_barrier_post(MacroAssembler* masm, Decorato
   assert(sizeof(*ct->card_table()->byte_map_base()) == sizeof(jbyte), "adjust this code");
 
   // Does store cross heap regions?
-  if (G1RSBarrierRegionFilter) {
-    __ xorr(tmp1, store_addr, new_val);
-    __ srdi_(tmp1, tmp1, HeapRegion::LogOfHRGrainBytes);
-    __ beq(CCR0, filtered);
-  }
+  __ xorr(tmp1, store_addr, new_val);
+  __ srdi_(tmp1, tmp1, HeapRegion::LogOfHRGrainBytes);
+  __ beq(CCR0, filtered);
 
   // Crosses regions, storing NULL?
   if (not_null) {

src/hotspot/cpu/s390/gc/g1/g1BarrierSetAssembler_s390.cpp

@@ -273,16 +273,14 @@ void G1BarrierSetAssembler::g1_write_barrier_post(MacroAssembler* masm, Decorato
 
   // Does store cross heap regions?
   // It does if the two addresses specify different grain addresses.
-  if (G1RSBarrierRegionFilter) {
-    if (VM_Version::has_DistinctOpnds()) {
-      __ z_xgrk(Rtmp1, Rstore_addr, Rnew_val);
-    } else {
-      __ z_lgr(Rtmp1, Rstore_addr);
-      __ z_xgr(Rtmp1, Rnew_val);
-    }
-    __ z_srag(Rtmp1, Rtmp1, HeapRegion::LogOfHRGrainBytes);
-    __ z_bre(filtered);
+  if (VM_Version::has_DistinctOpnds()) {
+    __ z_xgrk(Rtmp1, Rstore_addr, Rnew_val);
+  } else {
+    __ z_lgr(Rtmp1, Rstore_addr);
+    __ z_xgr(Rtmp1, Rnew_val);
   }
+  __ z_srag(Rtmp1, Rtmp1, HeapRegion::LogOfHRGrainBytes);
+  __ z_bre(filtered);
 
   // Crosses regions, storing NULL?
   if (not_null) {

src/hotspot/cpu/sparc/gc/g1/g1BarrierSetAssembler_sparc.cpp

@@ -369,12 +369,10 @@ void G1BarrierSetAssembler::g1_write_barrier_post(MacroAssembler* masm, Register
 
   G1BarrierSet* bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set());
 
-  if (G1RSBarrierRegionFilter) {
-    __ xor3(store_addr, new_val, tmp);
-    __ srlx(tmp, HeapRegion::LogOfHRGrainBytes, tmp);
+  __ xor3(store_addr, new_val, tmp);
+  __ srlx(tmp, HeapRegion::LogOfHRGrainBytes, tmp);
 
-    __ cmp_and_brx_short(tmp, G0, Assembler::equal, Assembler::pt, filtered);
-  }
+  __ cmp_and_brx_short(tmp, G0, Assembler::equal, Assembler::pt, filtered);
 
   // If the "store_addr" register is an "in" or "local" register, move it to
   // a scratch reg so we can pass it as an argument.

src/hotspot/share/gc/g1/g1_globals.hpp

@@ -108,9 +108,6 @@
           "When expanding, % of uncommitted space to claim.")               \
           range(0, 100)                                                     \
                                                                             \
-  develop(bool, G1RSBarrierRegionFilter, true,                              \
-          "If true, generate region filtering code in RS barrier")          \
-                                                                            \
   product(size_t, G1UpdateBufferSize, 256,                                  \
           "Size of an update buffer")                                       \
           range(1, NOT_LP64(32*M) LP64_ONLY(1*G))                           \