From d23330d49647d3b179c1213fe8fd95540f1b9fe4 Mon Sep 17 00:00:00 2001
From: "zhengxing.li" <zhengxing.li@intel.com>
Date: Sun, 22 Nov 2015 19:16:48 -0800
Subject: [PATCH] X87: Fix object initialization when slack tracking for it's
 map is still enabled.

  port 2fc2cb99f52974d0743610189213a94585c30ac6 (r32144)

  original commit message:
  The old code was not ready for properly initialize objects with non standard headers and non zero in-object properties number.

  MacroAssembler::Allocate() implementations now return both start and end addresses of the new object (done by parameter renaming).

BUG=

Review URL: https://codereview.chromium.org/1467923002

Cr-Commit-Position: refs/heads/master@{#32161}
---
 src/x87/builtins-x87.cc        | 14 ++++----------
 src/x87/macro-assembler-x87.cc | 10 +++++-----
 src/x87/macro-assembler-x87.h  | 11 +++++------
 3 files changed, 14 insertions(+), 21 deletions(-)

diff --git a/src/x87/builtins-x87.cc b/src/x87/builtins-x87.cc
index 651616aa6a..80141d3f46 100644
--- a/src/x87/builtins-x87.cc
+++ b/src/x87/builtins-x87.cc
@@ -241,18 +241,12 @@ static void Generate_JSConstructStubHelper(MacroAssembler* masm,
           __ j(less, &no_inobject_slack_tracking);
 
           // Allocate object with a slack.
-          __ movzx_b(
-              esi,
-              FieldOperand(
-                  eax,
-                  Map::kInObjectPropertiesOrConstructorFunctionIndexOffset));
-          __ movzx_b(eax, FieldOperand(eax, Map::kUnusedPropertyFieldsOffset));
-          __ sub(esi, eax);
-          __ lea(esi,
-                 Operand(ebx, esi, times_pointer_size, JSObject::kHeaderSize));
+          __ movzx_b(esi, FieldOperand(eax, Map::kUnusedPropertyFieldsOffset));
+          __ neg(esi);
+          __ lea(esi, Operand(edi, esi, times_pointer_size, 0));
           // esi: offset of first field after pre-allocated fields
           if (FLAG_debug_code) {
-            __ cmp(esi, edi);
+            __ cmp(ecx, esi);
             __ Assert(less_equal,
                       kUnexpectedNumberOfPreAllocatedPropertyFields);
           }
diff --git a/src/x87/macro-assembler-x87.cc b/src/x87/macro-assembler-x87.cc
index 0d2ff96dcb..a743380c60 100644
--- a/src/x87/macro-assembler-x87.cc
+++ b/src/x87/macro-assembler-x87.cc
@@ -1700,16 +1700,16 @@ void MacroAssembler::CopyBytes(Register source,
 }
 
 
-void MacroAssembler::InitializeFieldsWithFiller(Register start_offset,
-                                                Register end_offset,
+void MacroAssembler::InitializeFieldsWithFiller(Register current_address,
+                                                Register end_address,
                                                 Register filler) {
   Label loop, entry;
   jmp(&entry);
   bind(&loop);
-  mov(Operand(start_offset, 0), filler);
-  add(start_offset, Immediate(kPointerSize));
+  mov(Operand(current_address, 0), filler);
+  add(current_address, Immediate(kPointerSize));
   bind(&entry);
-  cmp(start_offset, end_offset);
+  cmp(current_address, end_address);
   j(below, &loop);
 }
 
diff --git a/src/x87/macro-assembler-x87.h b/src/x87/macro-assembler-x87.h
index 06dfdaf79d..481581eba9 100644
--- a/src/x87/macro-assembler-x87.h
+++ b/src/x87/macro-assembler-x87.h
@@ -685,12 +685,11 @@ class MacroAssembler: public Assembler {
                  Register length,
                  Register scratch);
 
-  // Initialize fields with filler values.  Fields starting at |start_offset|
-  // not including end_offset are overwritten with the value in |filler|.  At
-  // the end the loop, |start_offset| takes the value of |end_offset|.
-  void InitializeFieldsWithFiller(Register start_offset,
-                                  Register end_offset,
-                                  Register filler);
+  // Initialize fields with filler values.  Fields starting at |current_address|
+  // not including |end_address| are overwritten with the value in |filler|.  At
+  // the end the loop, |current_address| takes the value of |end_address|.
+  void InitializeFieldsWithFiller(Register current_address,
+                                  Register end_address, Register filler);
 
   // ---------------------------------------------------------------------------
   // Support functions.