[Isolates] Merge 6500:6700 from bleeding_edge to isolates.

src/ia32/macro-assembler-ia32.cc

 // Copyright 2011 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 588 matching lines @@
 
   // Load address of new object into result.
   LoadAllocationTopHelper(result, scratch, flags);
 
   Register top_reg = result_end.is_valid() ? result_end : result;
 
   // Calculate new top and bail out if new space is exhausted.
   ExternalReference new_space_allocation_limit =
       ExternalReference::new_space_allocation_limit_address();
 
-  if (top_reg.is(result)) {
-    add(Operand(top_reg), Immediate(object_size));
-  } else {
-    lea(top_reg, Operand(result, object_size));
+  if (!top_reg.is(result)) {
+    mov(top_reg, result);
   }
+  add(Operand(top_reg), Immediate(object_size));
+  j(carry, gc_required, not_taken);
   cmp(top_reg, Operand::StaticVariable(new_space_allocation_limit));
   j(above, gc_required, not_taken);
 
   // Update allocation top.
   UpdateAllocationTopHelper(top_reg, scratch);
 
   // Tag result if requested.
   if (top_reg.is(result)) {
     if ((flags & TAG_OBJECT) != 0) {
       sub(Operand(result), Immediate(object_size - kHeapObjectTag));
@@ skipping 28 matching lines @@
     return;
   }
   ASSERT(!result.is(result_end));
 
   // Load address of new object into result.
   LoadAllocationTopHelper(result, scratch, flags);
 
   // Calculate new top and bail out if new space is exhausted.
   ExternalReference new_space_allocation_limit =
       ExternalReference::new_space_allocation_limit_address();
-  lea(result_end, Operand(result, element_count, element_size, header_size));
+
+  // We assume that element_count*element_size + header_size does not
+  // overflow.
+  lea(result_end, Operand(element_count, element_size, header_size));
+  add(result_end, Operand(result));
+  j(carry, gc_required);
   cmp(result_end, Operand::StaticVariable(new_space_allocation_limit));
   j(above, gc_required);
 
   // Tag result if requested.
   if ((flags & TAG_OBJECT) != 0) {
     lea(result, Operand(result, kHeapObjectTag));
   }
 
   // Update allocation top.
   UpdateAllocationTopHelper(result_end, scratch);
@@ skipping 24 matching lines @@
   // Load address of new object into result.
   LoadAllocationTopHelper(result, scratch, flags);
 
   // Calculate new top and bail out if new space is exhausted.
   ExternalReference new_space_allocation_limit =
       ExternalReference::new_space_allocation_limit_address();
   if (!object_size.is(result_end)) {
     mov(result_end, object_size);
   }
   add(result_end, Operand(result));
+  j(carry, gc_required, not_taken);
   cmp(result_end, Operand::StaticVariable(new_space_allocation_limit));
   j(above, gc_required, not_taken);
 
   // Tag result if requested.
   if ((flags & TAG_OBJECT) != 0) {
     lea(result, Operand(result, kHeapObjectTag));
   }
 
   // Update allocation top.
   UpdateAllocationTopHelper(result_end, scratch);
@@ skipping 804 matching lines @@
 void MacroAssembler::LoadContext(Register dst, int context_chain_length) {
   if (context_chain_length > 0) {
     // Move up the chain of contexts to the context containing the slot.
     mov(dst, Operand(esi, Context::SlotOffset(Context::CLOSURE_INDEX)));
     // Load the function context (which is the incoming, outer context).
     mov(dst, FieldOperand(dst, JSFunction::kContextOffset));
     for (int i = 1; i < context_chain_length; i++) {
       mov(dst, Operand(dst, Context::SlotOffset(Context::CLOSURE_INDEX)));
       mov(dst, FieldOperand(dst, JSFunction::kContextOffset));
     }
-    // The context may be an intermediate context, not a function context.
-    mov(dst, Operand(dst, Context::SlotOffset(Context::FCONTEXT_INDEX)));
-  } else {  // Slot is in the current function context.
-    // The context may be an intermediate context, not a function context.
-    mov(dst, Operand(esi, Context::SlotOffset(Context::FCONTEXT_INDEX)));
+  } else {
+    // Slot is in the current function context.  Move it into the
+    // destination register in case we store into it (the write barrier
+    // cannot be allowed to destroy the context in esi).
+    mov(dst, esi);
+  }
+
+  // We should not have found a 'with' context by walking the context chain
+  // (i.e., the static scope chain and runtime context chain do not agree).
+  // A variable occurring in such a scope should have slot type LOOKUP and
+  // not CONTEXT.
+  if (FLAG_debug_code) {
+    cmp(dst, Operand(dst, Context::SlotOffset(Context::FCONTEXT_INDEX)));
+    Check(equal, "Yo dawg, I heard you liked function contexts "
+                 "so I put function contexts in all your contexts");
   }
 }
 
 
 void MacroAssembler::LoadGlobalFunction(int index, Register function) {
   // Load the global or builtins object from the current context.
   mov(function, Operand(esi, Context::SlotOffset(Context::GLOBAL_INDEX)));
   // Load the global context from the global or builtins object.
   mov(function, FieldOperand(function, GlobalObject::kGlobalContextOffset));
   // Load the function from the global context.
@@ skipping 23 matching lines @@
   ASSERT(reg_code >= 0 && reg_code < kNumSafepointRegisters);
   return kNumSafepointRegisters - reg_code - 1;
 }
 
 
 void MacroAssembler::Ret() {
   ret(0);
 }
 
 
+void MacroAssembler::Ret(int bytes_dropped, Register scratch) {
+  if (is_uint16(bytes_dropped)) {
+    ret(bytes_dropped);
+  } else {
+    pop(scratch);
+    add(Operand(esp), Immediate(bytes_dropped));
+    push(scratch);
+    ret(0);
+  }
+}
+
+
+
+
 void MacroAssembler::Drop(int stack_elements) {
   if (stack_elements > 0) {
     add(Operand(esp), Immediate(stack_elements * kPointerSize));
   }
 }
 
 
 void MacroAssembler::Move(Register dst, Register src) {
   if (!dst.is(src)) {
     mov(dst, src);
@@ skipping 313 matching lines @@
 
   // Check that the code was patched as expected.
   ASSERT(masm_.pc_ == address_ + size_);
   ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32