Initial implementation of fast path operation for bitwise OR.

src/x64/fast-codegen-x64.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
@@ skipping 17 matching lines @@
 #include "v8.h"
 
 #include "codegen-inl.h"
 #include "fast-codegen.h"
 
 namespace v8 {
 namespace internal {
 
 #define __ ACCESS_MASM(masm())
 
-// Registers rcx, rdi, and r8-r15 are free to use as scratch registers
-// without saving and restoring any other registers.
 Register FastCodeGenerator::accumulator0() { return rax; }
 Register FastCodeGenerator::accumulator1() { return rdx; }
 Register FastCodeGenerator::scratch0() { return rcx; }
 Register FastCodeGenerator::scratch1() { return rdi; }
 Register FastCodeGenerator::receiver_reg() { return rbx; }
 Register FastCodeGenerator::context_reg() { return rsi; }
 
 
 void FastCodeGenerator::EmitLoadReceiver() {
   // Offset 2 is due to return address and saved frame pointer.
   int index = 2 + scope()->num_parameters();
   __ movq(receiver_reg(), Operand(rbp, index * kPointerSize));
 }
 
 
 void FastCodeGenerator::EmitGlobalVariableLoad(Handle<Object> cell) {
+  ASSERT(!destination().is(no_reg));
   ASSERT(cell->IsJSGlobalPropertyCell());
-  __ Move(accumulator0(), cell);
-  __ movq(accumulator0(),
-          FieldOperand(accumulator0(), JSGlobalPropertyCell::kValueOffset));
+  __ Move(destination(), cell);
+  __ movq(destination(),
+          FieldOperand(destination(), JSGlobalPropertyCell::kValueOffset));
   if (FLAG_debug_code) {
-    __ Cmp(accumulator0(), Factory::the_hole_value());
+    __ Cmp(destination(), Factory::the_hole_value());
     __ Check(not_equal, "DontDelete cells can't contain the hole");
   }
 }
 
 
 void FastCodeGenerator::EmitThisPropertyStore(Handle<String> name) {
   LookupResult lookup;
   info()->receiver()->Lookup(*name, &lookup);
 
   ASSERT(lookup.holder() == *info()->receiver());
   ASSERT(lookup.type() == FIELD);
   Handle<Map> map(Handle<HeapObject>::cast(info()->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();
     __ movq(scratch0(), receiver_reg());  // Copy receiver for write barrier.
   } else {
     offset += FixedArray::kHeaderSize;
     __ movq(scratch0(),
             FieldOperand(receiver_reg(), JSObject::kPropertiesOffset));
   }
   // Perform the store.
   __ movq(FieldOperand(scratch0(), offset), accumulator0());
-  // Preserve value from write barrier in case it's needed.
-  __ movq(accumulator1(), accumulator0());
-  // The other accumulator register is available as a scratch register
-  // because this is not an AST leaf node.
-  __ RecordWrite(scratch0(), offset, accumulator1(), scratch1());
+  if (destination().is(no_reg)) {
+    __ RecordWrite(scratch0(), offset, accumulator0(), scratch1());
+  } else {
+    // Copy the value to the other accumulator to preserve a copy from the
+    // write barrier. One of the accumulators is available as a scratch
+    // register.
+    __ movq(accumulator1(), accumulator0());
+    Register value_scratch = other_accumulator(destination());
+    __ RecordWrite(scratch0(), offset, value_scratch, scratch1());
+  }
 }
 
 
+void FastCodeGenerator::EmitThisPropertyLoad(Handle<String> name) {
+  ASSERT(!destination().is(no_reg));
+  LookupResult lookup;
+  info()->receiver()->Lookup(*name, &lookup);
+
+  ASSERT(lookup.holder() == *info()->receiver());
+  ASSERT(lookup.type() == FIELD);
+  Handle<Map> map(Handle<HeapObject>::cast(info()->receiver())->map());
+  int index = lookup.GetFieldIndex() - map->inobject_properties();
+  int offset = index * kPointerSize;
+
+  // Perform the load.  Negative offsets are inobject properties.
+  if (offset < 0) {
+    offset += map->instance_size();
+    __ movq(destination(), FieldOperand(receiver_reg(), offset));
+  } else {
+    offset += FixedArray::kHeaderSize;
+    __ movq(scratch0(),
+            FieldOperand(receiver_reg(), JSObject::kPropertiesOffset));
+    __ movq(destination(), FieldOperand(scratch0(), offset));
+  }
+}
+
+
+void FastCodeGenerator::EmitBitOr() {
+  Register copied;  // One operand is copied to a scratch register.
+  Register other;   // The other is not modified by the operation.
+  Register check;   // A register is used for the smi check/operation.
+  if (destination().is(no_reg)) {
+    copied = accumulator1();  // Arbitrary choice of operand to copy.
+    other = accumulator0();
+    check = scratch0();  // Do not clobber either operand register.
+  } else {
+    copied = destination();
+    other = other_accumulator(destination());
+    check = destination();
+  }
+  __ movq(scratch0(), copied);
+  __ or_(check, other);
+  // Restore the clobbered operand if necessary.
+  if (destination().is(no_reg)) {
+    __ JumpIfNotSmi(check, bailout());
+  } else {
+    Label done;
+    __ JumpIfSmi(check, &done);
+    __ movq(copied, scratch0());
+    __ jmp(bailout());
+    __ bind(&done);
+  }
+}
+
+
 void FastCodeGenerator::Generate(CompilationInfo* compilation_info) {
   ASSERT(info_ == NULL);
   info_ = compilation_info;
 
   // Save the caller's frame pointer and set up our own.
   Comment prologue_cmnt(masm(), ";; Prologue");
   __ push(rbp);
   __ movq(rbp, rsp);
   __ push(rsi);  // Context.
   __ push(rdi);  // Closure.
@@ skipping 38 matching lines @@
   __ ret((scope()->num_parameters() + 1) * kPointerSize);
 
   __ bind(&bailout_);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal