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

src/arm/fast-codegen-arm.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();
+  __ ldr(reg, MemOperand(sp, index * kPointerSize));
+}
+
+
+void FastCodeGenerator::EmitReceiverMapCheck() {
+  Comment cmnt(masm(), ";; MapCheck(this)");
+  if (FLAG_print_ir) {
+    PrintF("MapCheck(this)\n");
+  }
+
+  EmitLoadReceiver(r1);
+  __ BranchOnSmi(r1, bailout());
+
+  ASSERT(has_receiver() && receiver()->IsHeapObject());
+  Handle<HeapObject> object = Handle<HeapObject>::cast(receiver());
+  Handle<Map> map(object->map());
+  __ ldr(r3, FieldMemOperand(r1, HeapObject::kMapOffset));
+  __ mov(ip, Operand(map));
+  __ cmp(r3, ip);
+  __ b(ne, bailout());
+}
+
+
+void FastCodeGenerator::EmitGlobalVariableLoad(Handle<String> name) {
+  // Compile global variable accesses as load IC calls.  The only live
+  // registers are cp (context) and possibly r1 (this).  Both are also saved
+  // in the stack and cp is preserved by the call.
+  __ ldr(ip, CodeGenerator::GlobalObject());
+  __ push(ip);
+  __ mov(r2, Operand(name));
+  Handle<Code> ic(Builtins::builtin(Builtins::LoadIC_Initialize));
+  __ Call(ic, RelocInfo::CODE_TARGET_CONTEXT);
+  if (has_this_properties()) {
+    // Restore this.
+    EmitLoadReceiver(r1);
+  }
+}
+
+
+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(r2, r1);  // Copy receiver for write barrier.
+  } else {
+    offset += FixedArray::kHeaderSize;
+    __ ldr(r2, FieldMemOperand(r1, JSObject::kPropertiesOffset));
+  }
+  // Perform the store.
+  __ str(r0, FieldMemOperand(r2, offset));
+  __ mov(r3, Operand(offset));
+  __ RecordWrite(r2, r3, ip);
+}
+
+
+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");
+  __ stm(db_w, sp, r1.bit() | cp.bit() | fp.bit() | lr.bit());
+  // Note that we keep a live register reference to cp (context) at
+  // this point.
+
+  // Receiver (this) is allocated to r1 if there are this properties.
+  if (has_this_properties()) EmitReceiverMapCheck();
+
+  VisitStatements(fun->body());
+
+  Comment return_cmnt(masm(), ";; Return(<undefined>)");
+  __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
+
+  Comment epilogue_cmnt(masm(), ";; Epilogue");
+  __ mov(sp, fp);
+  __ ldm(ia_w, sp, fp.bit() | lr.bit());
+  int32_t sp_delta = (fun->scope()->num_parameters() + 1) * kPointerSize;
+  __ add(sp, sp, Operand(sp_delta));
+  __ Jump(lr);
+
+  __ bind(&bailout_);
+}
+
+
+#undef __
+
+
+} }  // namespace v8::internal