Simplify handling of IC and megamorphic cache misses.

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 474 matching lines @@
   __ lw(T3, Address(T1));
   __ addiu(A1, A1, Immediate(-Smi::RawValue(1)));
   __ addiu(T1, T1, Immediate(-kWordSize));
   __ addiu(T2, T2, Immediate(kWordSize));
   __ bgez(A1, &loop);
   __ delay_slot()->sw(T3, Address(T2, -kWordSize));
   __ Bind(&loop_exit);
 }
 
 
-// Input parameters:
-//   S5: ic-data.
-//   S4: arguments descriptor array.
-// Note: The receiver object is the first argument to the function being
-//       called, the stub accesses the receiver from this location directly
-//       when trying to resolve the call.
-void StubCode::GenerateInstanceFunctionLookupStub(Assembler* assembler) {
-  __ TraceSimMsg("InstanceFunctionLookupStub");
-  __ EnterStubFrame();
-
-  // Load the receiver.
-  __ lw(A1, FieldAddress(S4, ArgumentsDescriptor::count_offset()));
-  __ sll(TMP, A1, 1);  // A1 is Smi.
-  __ addu(TMP, FP, TMP);
-  __ lw(T1, Address(TMP, kParamEndSlotFromFp * kWordSize));
-
-  // Push space for the return value.
-  // Push the receiver.
-  // Push TMP data object.
-  // Push arguments descriptor array.
-  __ addiu(SP, SP, Immediate(-4 * kWordSize));
-  __ LoadImmediate(TMP, reinterpret_cast<intptr_t>(Object::null()));
-  __ sw(TMP, Address(SP, 3 * kWordSize));
-  __ sw(T1, Address(SP, 2 * kWordSize));
-  __ sw(S5, Address(SP, 1 * kWordSize));
-  __ sw(S4, Address(SP, 0 * kWordSize));
-
-  // A1: Smi-tagged arguments array length.
-  PushArgumentsArray(assembler);
-  __ TraceSimMsg("InstanceFunctionLookupStub return");
-
-  __ CallRuntime(kInstanceFunctionLookupRuntimeEntry, 4);
-
-  __ lw(V0, Address(SP, 4 * kWordSize));  // Get result into V0.
-  __ addiu(SP, SP, Immediate(5 * kWordSize));    // Remove arguments.
-
-  __ LeaveStubFrameAndReturn();
-}
-
-
 DECLARE_LEAF_RUNTIME_ENTRY(intptr_t, DeoptimizeCopyFrame,
                            intptr_t deopt_reason,
                            uword saved_registers_address);
 
 DECLARE_LEAF_RUNTIME_ENTRY(void, DeoptimizeFillFrame, uword last_fp);
 
 
 // Used by eager and lazy deoptimization. Preserve result in V0 if necessary.
 // This stub translates optimized frame into unoptimized frame. The optimized
 // frame can contain values in registers and on stack, the unoptimized
@@ skipping 156 matching lines @@
   // Push IC data object.
   // Push arguments descriptor array.
   __ LoadImmediate(TMP, reinterpret_cast<intptr_t>(Object::null()));
   __ sw(TMP, Address(SP, 3 * kWordSize));
   __ sw(T6, Address(SP, 2 * kWordSize));
   __ sw(S5, Address(SP, 1 * kWordSize));
   __ sw(S4, Address(SP, 0 * kWordSize));
 
   __ CallRuntime(kMegamorphicCacheMissHandlerRuntimeEntry, 3);
 
-  __ lw(T0, Address(SP, 3 * kWordSize));  // Get result.
+  __ lw(T0, Address(SP, 3 * kWordSize));  // Get result function.
   __ lw(S4, Address(SP, 4 * kWordSize));  // Restore argument descriptor.
   __ lw(S5, Address(SP, 5 * kWordSize));  // Restore IC data.
   __ addiu(SP, SP, Immediate(6 * kWordSize));
 
   __ LeaveStubFrame();
 
-  Label nonnull;
-  __ BranchNotEqual(T0, reinterpret_cast<int32_t>(Object::null()), &nonnull);
-  __ Branch(&StubCode::InstanceFunctionLookupLabel());
-  __ Bind(&nonnull);
-  __ AddImmediate(T0, Instructions::HeaderSize() - kHeapObjectTag);
-  __ jr(T0);
+  __ lw(T2, FieldAddress(T0, Function::code_offset()));
+  __ lw(T2, FieldAddress(T2, Code::instructions_offset()));
+  __ AddImmediate(T2, Instructions::HeaderSize() - kHeapObjectTag);
+  __ jr(T2);
 }
 
 
 // Called for inline allocation of arrays.
 // Input parameters:
 //   RA: return address.
 //   A1: Array length as Smi.
 //   A0: array element type (either NULL or an instantiated type).
 // NOTE: A1 cannot be clobbered here as the caller relies on it being saved.
 // The newly allocated object is returned in V0.
@@ skipping 935 matching lines @@
   __ sw(TMP, Address(SP, (num_slots - 3) * kWordSize));
   // Push call arguments.
   for (intptr_t i = 0; i < num_args; i++) {
     __ lw(TMP, Address(T1, -i * kWordSize));
     __ sw(TMP, Address(SP, (num_slots - i - 4) * kWordSize));
   }
   // Pass IC data object.
   __ sw(S5, Address(SP, (num_slots - num_args - 4) * kWordSize));
   __ CallRuntime(handle_ic_miss, num_args + 1);
   __ TraceSimMsg("NArgsCheckInlineCacheStub return");
-  // Pop returned code object into T3 (null if not found).
+  // Pop returned function object into T3.
   // Restore arguments descriptor array and IC data array.
   __ lw(T3, Address(SP, (num_slots - 3) * kWordSize));
   __ lw(S4, Address(SP, (num_slots - 2) * kWordSize));
   __ lw(S5, Address(SP, (num_slots - 1) * kWordSize));
   // Remove the call arguments pushed earlier, including the IC data object
   // and the arguments descriptor array.
   __ addiu(SP, SP, Immediate(num_slots * kWordSize));
   __ LeaveStubFrame();
+
   Label call_target_function;
-  __ BranchNotEqual(T3, reinterpret_cast<int32_t>(Object::null()),
-                    &call_target_function);
-
-  // NoSuchMethod or closure.
-  // Mark IC call that it may be a closure call that does not collect
-  // type feedback.
-  __ LoadImmediate(T6, 1);
-  __ Branch(&StubCode::InstanceFunctionLookupLabel());
-  __ delay_slot()->sb(T6, FieldAddress(S5, ICData::is_closure_call_offset()));
+  __ b(&call_target_function);
 
   __ Bind(&found);
   // T0: Pointer to an IC data check group.
   const intptr_t target_offset = ICData::TargetIndexFor(num_args) * kWordSize;
   const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
   __ lw(T3, Address(T0, target_offset));
   __ lw(T4, Address(T0, count_offset));
 
   __ AddImmediateDetectOverflow(T4, T4, Smi::RawValue(1), T5, T6);
 
@@ skipping 532 matching lines @@
   const Register right = T0;
   __ lw(left, Address(SP, 1 * kWordSize));
   __ lw(right, Address(SP, 0 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp1, temp2);
   __ Ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS