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

src/arm/builtins-arm.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_ARM
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1212 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.
   __ Move(lr, masm->isolate()->builtins()->InterpreterEntryTrampoline());
 
   Generate_EnterBytecodeDispatch(masm);
 }
 
 
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- r0 : argument count (preserved for callee)
+  //  -- r3 : new target (preserved for callee)
+  //  -- r1 : 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 = r0;
+  Register closure = r1;
+  Register new_target = r3;
+  __ push(argument_count);
+  __ push(new_target);
+  __ push(closure);
+
+  Register map = argument_count;
+  Register index = r2;
+  __ ldr(map, FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
+  __ ldr(map,
+         FieldMemOperand(map, SharedFunctionInfo::kOptimizedCodeMapOffset));
+  __ ldr(index, FieldMemOperand(map, FixedArray::kLengthOffset));
+  __ cmp(index, Operand(Smi::FromInt(2)));
+  __ b(lt, &gotta_call_runtime);
+
+  // Find literals.
+  // r3  : native context
+  // r2  : length / index
+  // r0  : optimized code map
+  // stack[0] : new target
+  // stack[4] : closure
+  Register native_context = r3;
+  __ ldr(native_context, NativeContextMemOperand());
+
+  __ bind(&loop_top);
+  Register temp = r1;
+  Register array_pointer = r5;
+
+  // Does the native context match?
+  __ add(array_pointer, map, Operand::PointerOffsetFromSmiKey(index));
+  __ ldr(temp, FieldMemOperand(array_pointer,
+                               SharedFunctionInfo::OffsetToPreviousContext()));
+  __ ldr(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
+  __ cmp(temp, native_context);
+  __ b(ne, &loop_bottom);
+  // OSR id set to none?
+  __ ldr(temp, FieldMemOperand(array_pointer,
+                               SharedFunctionInfo::OffsetToPreviousOsrAstId()));
+  const int bailout_id = BailoutId::None().ToInt();
+  __ cmp(temp, Operand(Smi::FromInt(bailout_id)));
+  __ b(ne, &loop_bottom);
+  // Literals available?
+  __ ldr(temp, FieldMemOperand(array_pointer,
+                               SharedFunctionInfo::OffsetToPreviousLiterals()));
+  __ ldr(temp, FieldMemOperand(temp, WeakCell::kValueOffset));
+  __ JumpIfSmi(temp, &gotta_call_runtime);
+
+  // Save the literals in the closure.
+  __ ldr(r4, MemOperand(sp, 0));
+  __ str(temp, FieldMemOperand(r4, JSFunction::kLiteralsOffset));
+  __ push(index);
+  __ RecordWriteField(r4, JSFunction::kLiteralsOffset, temp, index,
+                      kLRHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+                      OMIT_SMI_CHECK);
+  __ pop(index);
+
+  // Code available?
+  Register entry = r4;
+  __ ldr(entry,
+         FieldMemOperand(array_pointer,
+                         SharedFunctionInfo::OffsetToPreviousCachedCode()));
+  __ ldr(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.
+  __ add(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
+
+  Label install_optimized_code_and_tailcall;
+  __ bind(&install_optimized_code_and_tailcall);
+  __ str(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset));
+  __ RecordWriteCodeEntryField(closure, entry, r5);
+
+  // Link the closure into the optimized function list.
+  // r4 : code entry
+  // r3 : native context
+  // r1 : closure
+  __ ldr(r5,
+         ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
+  __ str(r5, FieldMemOperand(closure, JSFunction::kNextFunctionLinkOffset));
+  __ RecordWriteField(closure, JSFunction::kNextFunctionLinkOffset, r5, r0,
+                      kLRHasNotBeenSaved, kDontSaveFPRegs, EMIT_REMEMBERED_SET,
+                      OMIT_SMI_CHECK);
+  const int function_list_offset =
+      Context::SlotOffset(Context::OPTIMIZED_FUNCTIONS_LIST);
+  __ str(closure,
+         ContextMemOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
+  // Save closure before the write barrier.
+  __ mov(r5, closure);
+  __ RecordWriteContextSlot(native_context, function_list_offset, closure, r0,
+                            kLRHasNotBeenSaved, kDontSaveFPRegs);
+  __ mov(closure, r5);
+  __ pop(new_target);
+  __ pop(argument_count);
+  __ Jump(entry);
+
+  __ bind(&loop_bottom);
+  __ sub(index, index, Operand(Smi::FromInt(SharedFunctionInfo::kEntryLength)));
+  __ cmp(index, Operand(Smi::FromInt(1)));
+  __ b(gt, &loop_top);
+
+  // 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.
+  __ ldr(entry, FieldMemOperand(map, FixedArray::kHeaderSize +
+                                         SharedFunctionInfo::kSharedCodeIndex));
+  __ ldr(entry, FieldMemOperand(entry, WeakCell::kValueOffset));
+  __ JumpIfSmi(entry, &try_shared);
+
+  // Store code entry in the closure.
+  __ add(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?
+  __ ldr(entry,
+         FieldMemOperand(closure, JSFunction::kSharedFunctionInfoOffset));
+  __ ldr(entry, FieldMemOperand(entry, SharedFunctionInfo::kCodeOffset));
+  __ ldr(r5, FieldMemOperand(entry, Code::kFlagsOffset));
+  __ and_(r5, r5, Operand(Code::KindField::kMask));
+  __ mov(r5, Operand(r5, LSR, Code::KindField::kShift));
+  __ cmp(r5, Operand(Code::BUILTIN));
+  __ b(eq, &gotta_call_runtime_no_stack);
+  // Yes, install the full code.
+  __ add(entry, entry, Operand(Code::kHeaderSize - kHeapObjectTag));
+  __ str(entry, FieldMemOperand(closure, JSFunction::kCodeEntryOffset));
+  __ RecordWriteCodeEntryField(closure, entry, r5);
+  __ 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 1379 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM