Visit the Optimized Code Map on first call rather than closure creation.

src/mips/builtins-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_MIPS
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1208 matching lines @@
   // This simulates the initial call to bytecode handlers in interpreter entry
   // trampoline. The return will never actually be taken, but our stack walker
   // uses this address to determine whether a frame is interpreted.
   __ li(ra, Operand(masm->isolate()->builtins()->InterpreterEntryTrampoline()));
 
   Generate_EnterBytecodeDispatch(masm);
 }
 
 
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- a0 : argument count (preserved for callee)
+  //  -- a3 : new target (preserved for callee)
+  //  -- a1 : target function (preserved for callee)
+  // -----------------------------------
+  // First lookup code, maybe we don't need to compile!
+  Label gotta_call_runtime, gotta_call_runtime_no_stack;
+  Label maybe_call_runtime;
+  Label try_shared;
+  Label loop_top, loop_bottom;
+
+  Register argument_count = a0;
+  Register closure = a1;
+  Register new_target = a3;
+  __ push(argument_count);
+  __ push(new_target);
+  __ push(closure);
+
+  Register map = a0;
+  Register index = a2;
+  __ lw(map, FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
+  __ lw(map, FieldMemOperand(map, SharedFunctionInfo::kOptimizedCodeMapOffset));
+  __ lw(index, FieldMemOperand(map, FixedArray::kLengthOffset));
+  __ Branch(&gotta_call_runtime, lt, index, Operand(Smi::FromInt(2)));
+
+  // Find literals.
+  // a3  : native context
+  // a2  : length / index
+  // a0  : optimized code map
+  // stack[0] : new target
+  // stack[4] : closure
+  Register native_context = a3;
+  __ lw(native_context, NativeContextMemOperand());
+
+  __ bind(&loop_top);
+  Register temp = a1;
+  Register array_pointer = t1;
+
+  // Does the native context match?
+  __ sll(at, index, kPointerSizeLog2 - kSmiTagSize);
+  __ Addu(array_pointer, map, Operand(at));
+  __ lw(temp, FieldMemOperand(array_pointer,
+                              SharedFunctionInfo::kOffsetToPreviousContext));
+  __ lw(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
+  __ Branch(&loop_bottom, ne, temp, Operand(native_context));
+  // OSR id set to none?
+  __ lw(temp, FieldMemOperand(array_pointer,
+                              SharedFunctionInfo::kOffsetToPreviousOsrAstId));
+  const int bailout_id = BailoutId::None().ToInt();
+  __ Branch(&loop_bottom, ne, temp, Operand(Smi::FromInt(bailout_id)));
+  // Literals available?
+  __ lw(temp, FieldMemOperand(array_pointer,
+                              SharedFunctionInfo::kOffsetToPreviousLiterals));
+  __ lw(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
+  __ JumpIfSmi(temp, &gotta_call_runtime);
+
+  // Save the literals in the closure.
+  __ lw(t0, MemOperand(sp, 0));
+  __ sw(temp, FieldMemOperand(t0, JSFunction::kLiteralsOffset));
+  __ push(index);
+  __ RecordWriteField(t0, JSFunction::kLiteralsOffset, temp, index,
+                      kRAHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+                      OMIT_SMI_CHECK);
+  __ pop(index);
+
+  // Code available?
+  Register entry = t0;
+  __ lw(entry,
+        FieldMemOperand(array_pointer,
+                        SharedFunctionInfo::kOffsetToPreviousCachedCode));
+  __ lw(entry, FieldMemOperand(entry, WeakCell::kValueOffset));
+  __ JumpIfSmi(entry, &maybe_call_runtime);
+
+  // Found literals and code. Get them into the closure and return.
+  __ pop(closure);
+  // Store code entry in the closure.
+  __ Addu(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
+
+  Label install_optimized_code_and_tailcall;
+  __ bind(&install_optimized_code_and_tailcall);
+  __ sw(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset));
+  __ RecordWriteCodeEntryField(closure, entry, t1);
+
+  // Link the closure into the optimized function list.
+  // t0 : code entry
+  // a3 : native context
+  // a1 : closure
+  __ lw(t1,
+        ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
+  __ sw(t1, FieldMemOperand(closure, JSFunction::kNextFunctionLinkOffset));
+  __ RecordWriteField(closure, JSFunction::kNextFunctionLinkOffset, t1, a0,
+                      kRAHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+                      OMIT_SMI_CHECK);
+  const int function_list_offset =
+      Context::SlotOffset(Context::OPTIMIZED_FUNCTIONS_LIST);
+  __ sw(closure,
+        ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
+  // Save closure before the write barrier.
+  __ mov(t1, closure);
+  __ RecordWriteContextSlot(native_context, function_list_offset, closure, a0,
+                            kRAHasNotBeenSaved, kDontSaveFPRegs);
+  __ mov(closure, t1);
+  __ pop(new_target);
+  __ pop(argument_count);
+  __ Jump(entry);
+
+  __ bind(&loop_bottom);
+  __ Subu(index, index,
+          Operand(Smi::FromInt(SharedFunctionInfo::kEntryLength)));
+  __ Branch(&loop_top, gt, index, Operand(Smi::FromInt(1)));
+
+  // We found neither literals nor code.
+  __ jmp(&gotta_call_runtime);
+
+  __ bind(&maybe_call_runtime);
+  __ pop(closure);
+
+  // Last possibility. Check the context free optimized code map entry.
+  __ lw(entry, FieldMemOperand(map, FixedArray::kHeaderSize +
+                                        SharedFunctionInfo::kSharedCodeIndex));
+  __ lw(entry, FieldMemOperand(entry, WeakCell::kValueOffset));
+  __ JumpIfSmi(entry, &try_shared);
+
+  // Store code entry in the closure.
+  __ Addu(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ jmp(&install_optimized_code_and_tailcall);
+
+  __ bind(&try_shared);
+  __ pop(new_target);
+  __ pop(argument_count);
+  // Is the full code valid?
+  __ lw(entry, FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
+  __ lw(entry, FieldMemOperand(entry, SharedFunctionInfo::kCodeOffset));
+  __ lw(t1, FieldMemOperand(entry, Code::kFlagsOffset));
+  __ And(t1, t1, Operand(Code::KindField::kMask));
+  __ srl(t1, t1, Code::KindField::kShift);
+  __ Branch(&gotta_call_runtime_no_stack, eq, t1, Operand(Code::BUILTIN));
+  // Yes, install the full code.
+  __ Addu(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ sw(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset));
+  __ RecordWriteCodeEntryField(closure, entry, t1);
+  __ Jump(entry);
+
+  __ bind(&gotta_call_runtime);
+  __ pop(closure);
+  __ pop(new_target);
+  __ pop(argument_count);
+  __ bind(&gotta_call_runtime_no_stack);
   GenerateTailCallToReturnedCode(masm, Runtime::kCompileLazy);
 }
 
 
 void Builtins::Generate_CompileOptimized(MacroAssembler* masm) {
   GenerateTailCallToReturnedCode(masm,
                                  Runtime::kCompileOptimized_NotConcurrent);
 }
 
 
@@ skipping 1469 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS