Precompilation: Have instances calls load the entry point and Code object from the ic data array in…

runtime/vm/stub_code_x64.cc

Index: runtime/vm/stub_code_x64.cc
diff --git a/runtime/vm/stub_code_x64.cc b/runtime/vm/stub_code_x64.cc
index b33ee0198bf6545dd8bc14998b367d5f6119498e..a8ed6ef68de339f02a56dd1629c1026871839fe7 100644
--- a/runtime/vm/stub_code_x64.cc
+++ b/runtime/vm/stub_code_x64.cc
@@ -2144,7 +2144,7 @@ void StubCode::GenerateMegamorphicLookupStub(Assembler* assembler) {
 //  RCX: target entry point
 //  CODE_REG: target Code object
 //  R10: arguments descriptor
-void StubCode::GenerateICLookupStub(Assembler* assembler) {
+void StubCode::GenerateICLookupThroughFunctionStub(Assembler* assembler) {
   Label loop, found, miss;
 
   __ movq(R13, FieldAddress(RBX, ICData::ic_data_offset()));
@@ -2181,6 +2181,44 @@ void StubCode::GenerateICLookupStub(Assembler* assembler) {
   __ ret();
 }
 
+
+void StubCode::GenerateICLookupThroughCodeStub(Assembler* assembler) {
+  Label loop, found, miss;
+
+  __ movq(R13, FieldAddress(RBX, ICData::ic_data_offset()));
+  __ movq(R10, FieldAddress(RBX, ICData::arguments_descriptor_offset()));
+  __ leaq(R13, FieldAddress(R13, Array::data_offset()));
+  // R13: first IC entry
+  __ LoadTaggedClassIdMayBeSmi(RAX, RDI);
+  // RAX: receiver cid as Smi
+
+  __ Bind(&loop);
+  __ movq(R9, Address(R13, 0));
+  __ cmpq(RAX, R9);
+  __ j(EQUAL, &found, Assembler::kNearJump);
+
+  ASSERT(Smi::RawValue(kIllegalCid) == 0);
+  __ testq(R9, R9);
+  __ j(ZERO, &miss, Assembler::kNearJump);
+
+  const intptr_t entry_length = ICData::TestEntryLengthFor(1) * kWordSize;
+  __ addq(R13, Immediate(entry_length));  // Next entry.
+  __ jmp(&loop);
+
+  __ Bind(&found);
+  const intptr_t code_offset = ICData::CodeIndexFor(1) * kWordSize;
+  const intptr_t entry_offset = ICData::EntryPointIndexFor(1) * kWordSize;
+  __ movq(RCX, Address(R13, entry_offset));
+  __ movq(CODE_REG, Address(R13, code_offset));
+  __ ret();
+
+  __ Bind(&miss);
+  __ LoadIsolate(RAX);
+  __ movq(CODE_REG, Address(RAX, Isolate::ic_miss_code_offset()));
+  __ movq(RCX, FieldAddress(CODE_REG, Code::entry_point_offset()));
+  __ ret();
+}
+
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64