Splits up dependent load in update of allocation stats.

runtime/vm/assembler_arm.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/assembler.h"
 #include "vm/cpu.h"
 #include "vm/longjump.h"
@@ skipping 3077 matching lines @@
 }
 
 
 void Assembler::LeaveStubFrame() {
   LeaveFrame((1 << PP) | (1 << FP) | (1 << LR));
   // Adjust SP for null PC pushed in EnterStubFrame.
   AddImmediate(SP, kWordSize);
 }
 
 
-void Assembler::UpdateAllocationStats(intptr_t cid,
-                                      Register temp_reg,
-                                      Heap::Space space) {
-  ASSERT(temp_reg != kNoRegister);
-  ASSERT(temp_reg != TMP);
+void Assembler::LoadAllocationStatsAddress(Register dest,
+                                           intptr_t cid,
+                                           Heap::Space space) {
+  ASSERT(dest != kNoRegister);
+  ASSERT(dest != TMP);
   ASSERT(cid > 0);
   Isolate* isolate = Isolate::Current();
   ClassTable* class_table = isolate->class_table();
   if (cid < kNumPredefinedCids) {
     const uword class_heap_stats_table_address =
         class_table->PredefinedClassHeapStatsTableAddress();
     const uword class_offset = cid * sizeof(ClassHeapStats);  // NOLINT
-    const uword count_field_offset = (space == Heap::kNew) ?
-      ClassHeapStats::allocated_since_gc_new_space_offset() :
-      ClassHeapStats::allocated_since_gc_old_space_offset();
-    LoadImmediate(temp_reg, class_heap_stats_table_address + class_offset);
-    const Address& count_address = Address(temp_reg, count_field_offset);
-    ldr(TMP, count_address);
-    AddImmediate(TMP, 1);
-    str(TMP, count_address);
+    LoadImmediate(dest, class_heap_stats_table_address + class_offset);
   } else {
-    ASSERT(temp_reg != kNoRegister);
     const uword class_offset = cid * sizeof(ClassHeapStats);  // NOLINT
-    const uword count_field_offset = (space == Heap::kNew) ?
-      ClassHeapStats::allocated_since_gc_new_space_offset() :
-      ClassHeapStats::allocated_since_gc_old_space_offset();
-    LoadImmediate(temp_reg, class_table->ClassStatsTableAddress());
-    ldr(temp_reg, Address(temp_reg, 0));
-    AddImmediate(temp_reg, class_offset);
-    ldr(TMP, Address(temp_reg, count_field_offset));
-    AddImmediate(TMP, 1);
-    str(TMP, Address(temp_reg, count_field_offset));
+    LoadImmediate(dest, class_table->ClassStatsTableAddress());
+    ldr(dest, Address(dest, 0));
+    AddImmediate(dest, class_offset);
   }
 }
 
 
-void Assembler::UpdateAllocationStatsWithSize(intptr_t cid,
-                                              Register size_reg,
-                                              Register temp_reg,
-                                              Heap::Space space) {
-  ASSERT(temp_reg != kNoRegister);
-  ASSERT(temp_reg != TMP);
+void Assembler::IncrementAllocationStats(Register stats_addr_reg,
+                                         intptr_t cid,
+                                         Heap::Space space) {
+  ASSERT(stats_addr_reg != kNoRegister);
+  ASSERT(stats_addr_reg != TMP);
   ASSERT(cid > 0);
-  Isolate* isolate = Isolate::Current();
-  ClassTable* class_table = isolate->class_table();
-  if (cid < kNumPredefinedCids) {
-    const uword class_heap_stats_table_address =
-        class_table->PredefinedClassHeapStatsTableAddress();
-    const uword class_offset = cid * sizeof(ClassHeapStats);  // NOLINT
-    const uword count_field_offset = (space == Heap::kNew) ?
-      ClassHeapStats::allocated_since_gc_new_space_offset() :
-      ClassHeapStats::allocated_since_gc_old_space_offset();
-    const uword size_field_offset = (space == Heap::kNew) ?
-      ClassHeapStats::allocated_size_since_gc_new_space_offset() :
-      ClassHeapStats::allocated_size_since_gc_old_space_offset();
-    LoadImmediate(temp_reg, class_heap_stats_table_address + class_offset);
-    const Address& count_address = Address(temp_reg, count_field_offset);
-    const Address& size_address = Address(temp_reg, size_field_offset);
-    ldr(TMP, count_address);
-    AddImmediate(TMP, 1);
-    str(TMP, count_address);
-    ldr(TMP, size_address);
-    add(TMP, TMP, Operand(size_reg));
-    str(TMP, size_address);
-  } else {
-    ASSERT(temp_reg != kNoRegister);
-    const uword class_offset = cid * sizeof(ClassHeapStats);  // NOLINT
-    const uword count_field_offset = (space == Heap::kNew) ?
-      ClassHeapStats::allocated_since_gc_new_space_offset() :
-      ClassHeapStats::allocated_since_gc_old_space_offset();
-    const uword size_field_offset = (space == Heap::kNew) ?
-      ClassHeapStats::allocated_size_since_gc_new_space_offset() :
-      ClassHeapStats::allocated_size_since_gc_old_space_offset();
-    LoadImmediate(temp_reg, class_table->ClassStatsTableAddress());
-    ldr(temp_reg, Address(temp_reg, 0));
-    AddImmediate(temp_reg, class_offset);
-    ldr(TMP, Address(temp_reg, count_field_offset));
-    AddImmediate(TMP, 1);
-    str(TMP, Address(temp_reg, count_field_offset));
-    ldr(TMP, Address(temp_reg, size_field_offset));
-    add(TMP, TMP, Operand(size_reg));
-    str(TMP, Address(temp_reg, size_field_offset));
-  }
+  const uword count_field_offset = (space == Heap::kNew) ?
+    ClassHeapStats::allocated_since_gc_new_space_offset() :
+    ClassHeapStats::allocated_since_gc_old_space_offset();
+  const Address& count_address = Address(stats_addr_reg, count_field_offset);
+  ldr(TMP, count_address);
+  AddImmediate(TMP, 1);
+  str(TMP, count_address);
+}
+
+
+void Assembler::IncrementAllocationStatsWithSize(Register stats_addr_reg,
+                                                 Register size_reg,
+                                                 intptr_t cid,
+                                                 Heap::Space space) {
+  ASSERT(stats_addr_reg != kNoRegister);
+  ASSERT(stats_addr_reg != TMP);
+  ASSERT(cid > 0);
+  const uword count_field_offset = (space == Heap::kNew) ?
+    ClassHeapStats::allocated_since_gc_new_space_offset() :
+    ClassHeapStats::allocated_since_gc_old_space_offset();
+  const uword size_field_offset = (space == Heap::kNew) ?
+    ClassHeapStats::allocated_size_since_gc_new_space_offset() :
+    ClassHeapStats::allocated_size_since_gc_old_space_offset();
+  const Address& count_address = Address(stats_addr_reg, count_field_offset);
+  const Address& size_address = Address(stats_addr_reg, size_field_offset);
+  ldr(TMP, count_address);
+  AddImmediate(TMP, 1);
+  str(TMP, count_address);
+  ldr(TMP, size_address);
+  add(TMP, TMP, Operand(size_reg));
+  str(TMP, size_address);
 }
 
 
 void Assembler::TryAllocate(const Class& cls,
                             Label* failure,
                             Register instance_reg,
                             Register temp_reg) {
   ASSERT(failure != NULL);
   if (FLAG_inline_alloc) {
     ASSERT(instance_reg != temp_reg);
@@ skipping 13 matching lines @@
     // Could use ldm to load (top, end), but no benefit seen experimentally.
     ldr(IP, Address(temp_reg, end_address - top_address));
     cmp(IP, Operand(instance_reg));
     // fail if heap end unsigned less than or equal to instance_reg.
     b(failure, LS);
 
     // Successfully allocated the object, now update top to point to
     // next object start and store the class in the class field of object.
     str(instance_reg, Address(temp_reg));
 
+    LoadAllocationStatsAddress(temp_reg, cls.id(), space);
+
     ASSERT(instance_size >= kHeapObjectTag);
     AddImmediate(instance_reg, -instance_size + kHeapObjectTag);
-    UpdateAllocationStats(cls.id(), temp_reg, space);
 
     uword tags = 0;
     tags = RawObject::SizeTag::update(instance_size, tags);
     ASSERT(cls.id() != kIllegalCid);
     tags = RawObject::ClassIdTag::update(cls.id(), tags);
     LoadImmediate(IP, tags);
     str(IP, FieldAddress(instance_reg, Object::tags_offset()));
+
+    IncrementAllocationStats(temp_reg, cls.id(), space);
   } else {
     b(failure);
   }
 }
 
 
 void Assembler::TryAllocateArray(intptr_t cid,
                                  intptr_t instance_size,
                                  Label* failure,
                                  Register instance,
@@ skipping 10 matching lines @@
     b(failure, VS);
 
     // Check if the allocation fits into the remaining space.
     // instance: potential new object start.
     // end_address: potential next object start.
     LoadImmediate(temp2, heap->EndAddress(space));
     ldr(temp2, Address(temp2, 0));
     cmp(end_address, Operand(temp2));
     b(failure, CS);
 
+    LoadAllocationStatsAddress(temp2, cid, space);
+
     // Successfully allocated the object(s), now update top to point to
     // next object start and initialize the object.
     str(end_address, Address(temp1, 0));
     add(instance, instance, Operand(kHeapObjectTag));
-    LoadImmediate(temp2, instance_size);
-    UpdateAllocationStatsWithSize(cid, temp2, temp1, space);
 
     // Initialize the tags.
     // instance: new object start as a tagged pointer.
     uword tags = 0;
     tags = RawObject::ClassIdTag::update(cid, tags);
     tags = RawObject::SizeTag::update(instance_size, tags);
-    LoadImmediate(temp2, tags);
-    str(temp2, FieldAddress(instance, Array::tags_offset()));  // Store tags.
+    LoadImmediate(temp1, tags);
+    str(temp1, FieldAddress(instance, Array::tags_offset()));  // Store tags.
+
+    LoadImmediate(temp1, instance_size);
+    IncrementAllocationStatsWithSize(temp2, temp1, cid, space);
   } else {
     b(failure);
   }
 }
 
 
 void Assembler::Stop(const char* message) {
   if (FLAG_print_stop_message) {
     StubCode* stub_code = Isolate::Current()->stub_code();
     PushList((1 << R0) | (1 << IP) | (1 << LR));  // Preserve R0, IP, LR.
@@ skipping 136 matching lines @@
 
 
 const char* Assembler::FpuRegisterName(FpuRegister reg) {
   ASSERT((0 <= reg) && (reg < kNumberOfFpuRegisters));
   return fpu_reg_names[reg];
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM