X87: Remove frame pointer from StackHandler.

src/x87/macro-assembler-x87.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
@@ skipping 972 matching lines @@
   mov(esp, ebp);
   pop(ebp);
 
   LeaveExitFrameEpilogue(restore_context);
 }
 
 
 void MacroAssembler::PushTryHandler(StackHandler::Kind kind,
                                     int handler_index) {
   // Adjust this code if not the case.
-  STATIC_ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
+  STATIC_ASSERT(StackHandlerConstants::kSize == 3 * kPointerSize);
   STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
   STATIC_ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize);
   STATIC_ASSERT(StackHandlerConstants::kContextOffset == 2 * kPointerSize);
-  STATIC_ASSERT(StackHandlerConstants::kFPOffset == 3 * kPointerSize);
 
   // We will build up the handler from the bottom by pushing on the stack.
-  // First push the frame pointer and context.
+  // First push the context.
   if (kind == StackHandler::JS_ENTRY) {
-    // The frame pointer does not point to a JS frame so we save NULL for
-    // ebp. We expect the code throwing an exception to check ebp before
-    // dereferencing it to restore the context.
-    push(Immediate(0));  // NULL frame pointer.
     push(Immediate(Smi::FromInt(0)));  // No context.
   } else {
-    push(ebp);
     push(esi);
   }
   // Push the state.
   unsigned state =
       StackHandler::IndexField::encode(handler_index) |
       StackHandler::KindField::encode(kind);
   push(Immediate(state));
 
   // Link the current handler as the next handler.
   ExternalReference handler_address(Isolate::kHandlerAddress, isolate());
@@ skipping 2093 matching lines @@
   if (mag.shift > 0) sar(edx, mag.shift);
   mov(eax, dividend);
   shr(eax, 31);
   add(edx, eax);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X87