Reland "[turbofan] Discard the shared code entry in the optimized code map."

src/builtins/ia32/builtins-ia32.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_IA32
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1037 matching lines @@
 }
 
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- eax : argument count (preserved for callee)
   //  -- edx : new target (preserved for callee)
   //  -- edi : 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 closure = edi;
   Register new_target = edx;
   Register argument_count = eax;
 
   __ push(argument_count);
   __ push(new_target);
   __ push(closure);
@@ skipping 42 matching lines @@
   __ push(index);
   __ RecordWriteField(ecx, JSFunction::kLiteralsOffset, temp, index,
                       kDontSaveFPRegs, EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
   __ pop(index);
 
   // Code available?
   Register entry = ecx;
   __ mov(entry, FieldOperand(map, index, times_half_pointer_size,
                              SharedFunctionInfo::kOffsetToPreviousCachedCode));
   __ mov(entry, FieldOperand(entry, WeakCell::kValueOffset));
-  __ JumpIfSmi(entry, &maybe_call_runtime);
+  __ JumpIfSmi(entry, &try_shared);
 
   // Found literals and code. Get them into the closure and return.
   __ pop(closure);
   // Store code entry in the closure.
   __ lea(entry, FieldOperand(entry, Code::kHeaderSize));
-
-  Label install_optimized_code_and_tailcall;
-  __ bind(&install_optimized_code_and_tailcall);
   __ mov(FieldOperand(closure, JSFunction::kCodeEntryOffset), entry);
   __ RecordWriteCodeEntryField(closure, entry, eax);
 
   // Link the closure into the optimized function list.
   // ecx : code entry
   // edx : native context
   // edi : closure
   __ mov(ebx,
          ContextOperand(native_context, Context::OPTIMIZED_FUNCTIONS_LIST));
   __ mov(FieldOperand(closure, JSFunction::kNextFunctionLinkOffset), ebx);
@@ skipping 13 matching lines @@
   __ jmp(entry);
 
   __ bind(&loop_bottom);
   __ sub(index, Immediate(Smi::FromInt(SharedFunctionInfo::kEntryLength)));
   __ cmp(index, Immediate(Smi::FromInt(1)));
   __ j(greater, &loop_top);
 
   // We found neither literals nor code.
   __ jmp(&gotta_call_runtime);
 
-  __ bind(&maybe_call_runtime);
+  __ bind(&try_shared);
   __ pop(closure);
-
-  // Last possibility. Check the context free optimized code map entry.
-  __ mov(entry, FieldOperand(map, FixedArray::kHeaderSize +
-                                      SharedFunctionInfo::kSharedCodeIndex));
-  __ mov(entry, FieldOperand(entry, WeakCell::kValueOffset));
-  __ JumpIfSmi(entry, &try_shared);
-
-  // Store code entry in the closure.
-  __ lea(entry, FieldOperand(entry, Code::kHeaderSize));
-  __ jmp(&install_optimized_code_and_tailcall);
-
-  __ bind(&try_shared);
   __ pop(new_target);
   __ pop(argument_count);
   // Is the full code valid?
   __ mov(entry, FieldOperand(closure, JSFunction::kSharedFunctionInfoOffset));
   __ mov(entry, FieldOperand(entry, SharedFunctionInfo::kCodeOffset));
   __ mov(ebx, FieldOperand(entry, Code::kFlagsOffset));
   __ and_(ebx, Code::KindField::kMask);
   __ shr(ebx, Code::KindField::kShift);
   __ cmp(ebx, Immediate(Code::BUILTIN));
   __ j(equal, &gotta_call_runtime_no_stack);
@@ skipping 1955 matching lines @@
 
 void Builtins::Generate_InterpreterOnStackReplacement(MacroAssembler* masm) {
   Generate_OnStackReplacementHelper(masm, true);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32