Implement simple fast-path code for functions containing this property stores and global variables.

src/ia32/fast-codegen-ia32.cc

+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "v8.h"
+
+#include "codegen-inl.h"
+#include "fast-codegen.h"
+
+namespace v8 {
+namespace internal {
+
+#define __ ACCESS_MASM(masm())
+
+void FastCodeGenerator::EmitLoadReceiver(Register reg) {
+  // Offset 2 is due to return address and saved frame pointer.
+  int index = 2 + function()->scope()->num_parameters();
+  __ mov(reg, Operand(ebp, index * kPointerSize));
+}
+
+
+void FastCodeGenerator::EmitReceiverMapCheck() {
+  Comment cmnt(masm(), ";; MapCheck(this)");
+  if (FLAG_print_ir) {
+    PrintF("MapCheck(this)\n");
+  }
+
+  EmitLoadReceiver(edx);
+  __ test(edx, Immediate(kSmiTagMask));
+  __ j(zero, bailout());
+
+  ASSERT(has_receiver() && receiver()->IsHeapObject());
+  Handle<HeapObject> object = Handle<HeapObject>::cast(receiver());
+  Handle<Map> map(object->map());
+  __ cmp(FieldOperand(edx, HeapObject::kMapOffset), Immediate(map));
+  __ j(not_equal, bailout());
+}
+
+
+void FastCodeGenerator::EmitGlobalVariableLoad(Handle<String> name) {
+  // Compile global variable accesses as load IC calls.  The only live
+  // registers are esi (context) and possibly edx (this).  Both are also
+  // saved in the stack and esi is preserved by the call.
+  __ push(CodeGenerator::GlobalObject());
+  __ mov(ecx, name);
+  Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
+  __ call(ic, RelocInfo::CODE_TARGET_CONTEXT);
+  if (has_this_properties()) {
+    // Restore this.
+    EmitLoadReceiver(edx);
+  } else {
+    __ nop();  // Not test eax, indicates IC has no inlined code at call site.
+  }
+}
+
+
+void FastCodeGenerator::EmitThisPropertyStore(Handle<String> name) {
+  LookupResult lookup;
+  receiver()->Lookup(*name, &lookup);
+
+  ASSERT(lookup.holder() == *receiver());
+  ASSERT(lookup.type() == FIELD);
+  Handle<Map> map(Handle<HeapObject>::cast(receiver())->map());
+  int index = lookup.GetFieldIndex() - map->inobject_properties();
+  int offset = index * kPointerSize;
+
+  // Negative offsets are inobject properties.
+  if (offset < 0) {
+    offset += map->instance_size();
+    __ mov(ecx, edx);  // Copy receiver for write barrier.
+  } else {
+    offset += FixedArray::kHeaderSize;
+    __ mov(ecx, FieldOperand(edx, JSObject::kPropertiesOffset));
+  }
+  // Perform the store.
+  __ mov(FieldOperand(ecx, offset), eax);
+  // Preserve value from write barrier in case it's needed.
+  __ mov(ebx, eax);
+  __ RecordWrite(ecx, offset, ebx, edi);
+}
+
+
+void FastCodeGenerator::Generate(FunctionLiteral* fun, CompilationInfo* info) {
+  ASSERT(function_ == NULL);
+  ASSERT(info_ == NULL);
+  function_ = fun;
+  info_ = info;
+
+  // Save the caller's frame pointer and set up our own.
+  Comment prologue_cmnt(masm(), ";; Prologue");
+  __ push(ebp);
+  __ mov(ebp, esp);
+  __ push(esi);  // Context.
+  __ push(edi);  // Closure.
+  // Note that we keep a live register reference to esi (context) at this
+  // point.
+
+  // Receiver (this) is allocated to edx if there are this properties.
+  if (has_this_properties()) EmitReceiverMapCheck();
+
+  VisitStatements(fun->body());
+
+  Comment return_cmnt(masm(), ";; Return(<undefined>)");
+  __ mov(eax, Factory::undefined_value());
+
+  Comment epilogue_cmnt(masm(), ";; Epilogue");
+  __ mov(esp, ebp);
+  __ pop(ebp);
+  __ ret((fun->scope()->num_parameters() + 1) * kPointerSize);
+
+  __ bind(&bailout_);
+}
+
+
+#undef __
+
+
+} }  // namespace v8::internal