Specialize breakpoint stubs by set of live registers of the stubs they are intercepting.

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 16 matching lines @@
 DECLARE_FLAG(bool, trace_optimized_ic_calls);
 
 DECLARE_FLAG(bool, enable_debugger);
 
 // Input parameters:
 //   RA : return address.
 //   SP : address of last argument in argument array.
 //   SP + 4*S4 - 4 : address of first argument in argument array.
 //   SP + 4*S4 : address of return value.
 //   S5 : address of the runtime function to call.
-//   S4 : number of arguments to the call as Smi.
+//   S4 : number of arguments to the call.
 void StubCode::GenerateCallToRuntimeStub(Assembler* assembler) {
   const intptr_t isolate_offset = NativeArguments::isolate_offset();
   const intptr_t argc_tag_offset = NativeArguments::argc_tag_offset();
   const intptr_t argv_offset = NativeArguments::argv_offset();
   const intptr_t retval_offset = NativeArguments::retval_offset();
   const intptr_t exitframe_last_param_slot_from_fp = 2;
 
   __ SetPrologueOffset();
   __ TraceSimMsg("CallToRuntimeStub");
   __ addiu(SP, SP, Immediate(-3 * kWordSize));
   __ sw(ZR, Address(SP, 2 * kWordSize));  // Push 0 for the PC marker
   __ sw(RA, Address(SP, 1 * kWordSize));
   __ sw(FP, Address(SP, 0 * kWordSize));
   __ mov(FP, SP);
-  __ SmiUntag(S4);
 
   // Load current Isolate pointer from Context structure into A0.
   __ lw(A0, FieldAddress(CTX, Context::isolate_offset()));
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to Dart VM C++ code.
   __ sw(SP, Address(A0, Isolate::top_exit_frame_info_offset()));
 
   // Save current Context pointer into Isolate structure.
   __ sw(CTX, Address(A0, Isolate::top_context_offset()));
@@ skipping 1651 matching lines @@
   __ lw(S5, Address(SP, 2 * kWordSize));  // Restore IC data array.
   __ addiu(SP, SP, Immediate(3 * kWordSize));
   __ LeaveStubFrame();
 
   __ lw(T2, FieldAddress(T0, Function::instructions_offset()));
   __ AddImmediate(T2, Instructions::HeaderSize() - kHeapObjectTag);
   __ jr(T2);
 }
 
 
-void StubCode::GenerateBreakpointRuntimeStub(Assembler* assembler) {
-  __ Comment("BreakpointRuntime stub");
+// S5: Contains an ICData.
+void StubCode::GenerateICCallBreakpointStub(Assembler* assembler) {
+  __ Comment("ICCallBreakpoint stub");
+  __ EnterStubFrame();
+  __ addiu(SP, SP, Immediate(-2 * kWordSize));
+  __ sw(S5, Address(SP, 1 * kWordSize));
+  __ LoadImmediate(TMP, reinterpret_cast<intptr_t>(Object::null()));
+  __ sw(TMP, Address(SP, 0 * kWordSize));
+
+  __ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
+
+  __ lw(S5, Address(SP, 1 * kWordSize));
+  __ lw(T0, Address(SP, 0 * kWordSize));
+  __ addiu(SP, SP, Immediate(2 * kWordSize));
+  __ LeaveStubFrame();
+  __ jr(T0);
+}
+
+
+// S5: Contains Smi 0 (need to preserve a GC-safe value for the lazy compile
+// stub).
+// S4: Contains an arguments descriptor.
+void StubCode::GenerateClosureCallBreakpointStub(Assembler* assembler) {
+  __ Comment("ClosureCallBreakpoint stub");
   __ EnterStubFrame();
   __ addiu(SP, SP, Immediate(-3 * kWordSize));
   __ sw(S5, Address(SP, 2 * kWordSize));
   __ sw(S4, Address(SP, 1 * kWordSize));
   __ LoadImmediate(TMP, reinterpret_cast<intptr_t>(Object::null()));
   __ sw(TMP, Address(SP, 0 * kWordSize));
 
   __ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
 
   __ lw(S5, Address(SP, 2 * kWordSize));
   __ lw(S4, Address(SP, 1 * kWordSize));
   __ lw(T0, Address(SP, 0 * kWordSize));
   __ addiu(SP, SP, Immediate(3 * kWordSize));
   __ LeaveStubFrame();
   __ jr(T0);
 }
 
 
+// S5: Garbage or function address.
+// S4: Garbage or raw argument count.
+void StubCode::GenerateRuntimeCallBreakpointStub(Assembler* assembler) {
+  __ Comment("RuntimeCallBreakpoint stub");
+  __ EnterStubFrame();
+  __ addiu(SP, SP, Immediate(-3 * kWordSize));
+  __ AndImmediate(S5, S5, ~kSmiTagMask);
+  __ sw(S5, Address(SP, 2 * kWordSize));
+  __ SmiTag(S4);
+  __ sw(S4, Address(SP, 1 * kWordSize));
+  __ LoadImmediate(TMP, reinterpret_cast<intptr_t>(Object::null()));
+  __ sw(TMP, Address(SP, 0 * kWordSize));
+
+  __ CallRuntime(kBreakpointRuntimeHandlerRuntimeEntry, 0);
+
+  __ lw(S5, Address(SP, 2 * kWordSize));
+  __ lw(S4, Address(SP, 1 * kWordSize));
+  __ SmiUntag(S4);
+  __ lw(T0, Address(SP, 0 * kWordSize));
+  __ addiu(SP, SP, Immediate(3 * kWordSize));
+  __ LeaveStubFrame();
+  __ jr(T0);
+}
+
+
 // Called only from unoptimized code. All relevant registers have been saved.
 // RA: return address.
 void StubCode::GenerateDebugStepCheckStub(Assembler* assembler) {
   if (FLAG_enable_debugger) {
     // Check single stepping.
     Label not_stepping;
     __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
     __ lbu(T0, Address(T0, Isolate::single_step_offset()));
     __ BranchEqual(T0, 0, &not_stepping);
     // Call single step callback in debugger.
@@ skipping 308 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