Precompilation: Generate instance calls as IC calls that can switch to Megamoprhic calls.

runtime/vm/stub_code_mips.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_MIPS)
 
 #include "vm/assembler.h"
 #include "vm/code_generator.h"
 #include "vm/compiler.h"
@@ skipping 545 matching lines @@
   __ BranchNotEqual(T0, Object::null_object(), call_target_function);
   __ EnterStubFrame();
   // Load the receiver.
   __ lw(A1, FieldAddress(S4, ArgumentsDescriptor::count_offset()));
   __ sll(TMP, A1, 1);  // A1 is a Smi.
   __ addu(TMP, FP, TMP);
   __ lw(T6, Address(TMP, kParamEndSlotFromFp * kWordSize));
 
   // Push space for the return value.
   // Push the receiver.
-  // Push IC data object.
+  // Push ICData/MegamorphicCache object.
   // Push arguments descriptor array.
   // Push original arguments array.
   __ addiu(SP, SP, Immediate(-4 * kWordSize));
   __ LoadObject(TMP, Object::null_object());
   __ sw(TMP, Address(SP, 3 * kWordSize));
   __ sw(T6, Address(SP, 2 * kWordSize));
   __ sw(S5, Address(SP, 1 * kWordSize));
   __ sw(S4, Address(SP, 0 * kWordSize));
   // A1: Smi-tagged arguments array length.
   PushArgumentsArray(assembler);
@@ skipping 1627 matching lines @@
   const Register temp2 = T3;
   const Register left = T1;
   const Register right = T0;
   __ lw(left, Address(SP, 1 * kWordSize));
   __ lw(right, Address(SP, 0 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp1, temp2);
   __ Ret();
 }
 
 
-void StubCode::EmitMegamorphicLookup(
-    Assembler* assembler, Register receiver, Register cache, Register target) {
-  ASSERT((cache != T0) && (cache != T2));
-  __ LoadTaggedClassIdMayBeSmi(T0, receiver);
+void StubCode::EmitMegamorphicLookup(Assembler* assembler) {
+  __ LoadTaggedClassIdMayBeSmi(T0, T0);
   // T0: class ID of the receiver (smi).
-  __ lw(T2, FieldAddress(cache, MegamorphicCache::buckets_offset()));
-  __ lw(T1, FieldAddress(cache, MegamorphicCache::mask_offset()));
+  __ lw(S4, FieldAddress(S5, MegamorphicCache::arguments_descriptor_offset()));
+  __ lw(T2, FieldAddress(S5, MegamorphicCache::buckets_offset()));
+  __ lw(T1, FieldAddress(S5, MegamorphicCache::mask_offset()));
   // T2: cache buckets array.
   // T1: mask.
   __ mov(T3, T0);
+  // T3: probe.
 
   Label loop, update, call_target_function;
   __ b(&loop);
 
   __ Bind(&update);
   __ addiu(T3, T3, Immediate(Smi::RawValue(1)));
   __ Bind(&loop);
   __ and_(T3, T3, T1);
   const intptr_t base = Array::data_offset();
   // T3 is smi tagged, but table entries are two words, so LSL 2.
   __ sll(TMP, T3, 2);
   __ addu(TMP, T2, TMP);
   __ lw(T4, FieldAddress(TMP, base));
 
   ASSERT(kIllegalCid == 0);
   __ beq(T4, ZR, &call_target_function);
   __ bne(T4, T0, &update);
 
   __ Bind(&call_target_function);
   // Call the target found in the cache.  For a class id match, this is a
   // proper target for the given name and arguments descriptor.  If the
   // illegal class id was found, the target is a cache miss handler that can
   // be invoked as a normal Dart function.
   __ sll(T1, T3, 2);
   __ addu(T1, T2, T1);
   __ lw(T0, FieldAddress(T1, base + kWordSize));
 
+  __ lw(T1, FieldAddress(T0, Function::entry_point_offset()));
   __ lw(CODE_REG, FieldAddress(T0, Function::code_offset()));
-  __ lw(target, FieldAddress(T0, Function::entry_point_offset()));
 }
 
 
 // Called from megamorphic calls.
-//  T0: receiver.
-//  T1: lookup cache.
+//  T0: receiver
+//  S5: MegamorphicCache (preserved)
 // Result:
-//  T1: entry point.
+//  T1: target entry point
+//  CODE_REG: target Code
+//  S4: arguments descriptor
 void StubCode::GenerateMegamorphicLookupStub(Assembler* assembler) {
-  EmitMegamorphicLookup(assembler, T0, T1, T1);
+  EmitMegamorphicLookup(assembler);
   __ Ret();
 }
 
+
+// Called from switchable IC calls.
+//  T0: receiver
+//  S5: ICData (preserved)
+// Result:
+//  T1: target entry point
+//  CODE_REG: target Code object
+//  S4: arguments descriptor
+void StubCode::GenerateICLookupStub(Assembler* assembler) {
+  Label loop, found, miss;
+  __ lw(T6, FieldAddress(S5, ICData::ic_data_offset()));
+  __ lw(S4, FieldAddress(S5, ICData::arguments_descriptor_offset()));
+  __ AddImmediate(T6, T6, Array::data_offset() - kHeapObjectTag);
+  // T6: first IC entry.
+  __ LoadTaggedClassIdMayBeSmi(T1, T0);
+  // T1: receiver cid as Smi
+
+  __ Bind(&loop);
+  __ lw(T2, Address(T6, 0));
+  __ beq(T1, T2, &found);
+  ASSERT(Smi::RawValue(kIllegalCid) == 0);
+  __ beq(T2, ZR, &miss);
+
+  const intptr_t entry_length = ICData::TestEntryLengthFor(1) * kWordSize;
+  __ AddImmediate(T6, entry_length);  // Next entry.
+  __ b(&loop);
+
+  __ Bind(&found);
+  const intptr_t target_offset = ICData::TargetIndexFor(1) * kWordSize;
+  __ lw(T0, Address(T6, target_offset));
+  __ lw(CODE_REG, FieldAddress(T0, Function::code_offset()));
+  __ lw(T1, FieldAddress(T0, Function::entry_point_offset()));
+  __ Ret();
+
+  __ Bind(&miss);
+  __ LoadIsolate(T2);
+  __ lw(T0, Address(T2, Isolate::ic_miss_function_offset()));
+  __ lw(T1, FieldAddress(T0, Function::entry_point_offset()));
+  __ lw(CODE_REG, FieldAddress(T0, Function::code_offset()));
+  __ Ret();
+}
+
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS