Cleanup of ARM exception handlers. Remove the unused code and...

src/ia32/codegen-ia32.cc

 // Copyright 2006-2009 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 3234 matching lines @@
     has_unlinks = has_unlinks || shadows[i]->is_linked();
   }
   function_return_is_shadowed_ = function_return_was_shadowed;
 
   // Get an external reference to the handler address.
   ExternalReference handler_address(Top::k_handler_address);
 
   // Make sure that there's nothing left on the stack above the
   // handler structure.
   if (FLAG_debug_code) {
-    ASSERT(StackHandlerConstants::kAddressDisplacement == 0);
     __ mov(eax, Operand::StaticVariable(handler_address));
     __ cmp(esp, Operand(eax));
     __ Assert(equal, "stack pointer should point to top handler");
   }
 
   // If we can fall off the end of the try block, unlink from try chain.
   if (has_valid_frame()) {
     // The next handler address is on top of the frame.  Unlink from
     // the handler list and drop the rest of this handler from the
     // frame.
@@ skipping 18 matching lines @@
       } else {
         shadows[i]->Bind();
       }
       // Because we can be jumping here (to spilled code) from
       // unspilled code, we need to reestablish a spilled frame at
       // this block.
       frame_->SpillAll();
 
       // Reload sp from the top handler, because some statements that we
       // break from (eg, for...in) may have left stuff on the stack.
-      ASSERT(StackHandlerConstants::kAddressDisplacement == 0);
       __ mov(esp, Operand::StaticVariable(handler_address));
       frame_->Forget(frame_->height() - handler_height);
 
       ASSERT(StackHandlerConstants::kNextOffset == 0);
       frame_->EmitPop(Operand::StaticVariable(handler_address));
       frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
 
       if (i == kReturnShadowIndex) {
         if (!function_return_is_shadowed_) frame_->PrepareForReturn();
         shadows[i]->other_target()->Jump(&return_value);
@@ skipping 104 matching lines @@
         shadows[i]->Bind();
       }
       // Because we can be jumping here (to spilled code) from
       // unspilled code, we need to reestablish a spilled frame at
       // this block.
       frame_->SpillAll();
 
       // Reload sp from the top handler, because some statements that
       // we break from (eg, for...in) may have left stuff on the
       // stack.
-      ASSERT(StackHandlerConstants::kAddressDisplacement == 0);
       __ mov(esp, Operand::StaticVariable(handler_address));
       frame_->Forget(frame_->height() - handler_height);
 
       // Unlink this handler and drop it from the frame.
       ASSERT(StackHandlerConstants::kNextOffset == 0);
       frame_->EmitPop(Operand::StaticVariable(handler_address));
       frame_->Drop(StackHandlerConstants::kSize / kPointerSize - 1);
 
       if (i == kReturnShadowIndex) {
         // If this target shadowed the function return, materialize
@@ skipping 3518 matching lines @@
   __ Set(eax, Immediate(argc_));
   __ Set(ebx, Immediate(0));
   __ GetBuiltinEntry(edx, Builtins::CALL_NON_FUNCTION);
   Handle<Code> adaptor(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline));
   __ jmp(adaptor, RelocInfo::CODE_TARGET);
 }
 
 
 
 void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) {
+  // eax holds the exception.
+
   // Adjust this code if not the case.
   ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
 
   // Drop the sp to the top of the handler.
-  ASSERT(StackHandlerConstants::kAddressDisplacement == 0);
   ExternalReference handler_address(Top::k_handler_address);
   __ mov(esp, Operand::StaticVariable(handler_address));
 
   // Restore next handler and frame pointer, discard handler state.
   ASSERT(StackHandlerConstants::kNextOffset == 0);
   __ pop(Operand::StaticVariable(handler_address));
   ASSERT(StackHandlerConstants::kFPOffset == 1 * kPointerSize);
   __ pop(ebp);
   __ pop(edx);  // Remove state.
 
-  // Before returning we restore the context from the frame pointer if not NULL.
-  // The frame pointer is NULL in the exception handler of a JS entry frame.
-  __ xor_(esi, Operand(esi));  // tentatively set context pointer to NULL
+  // Before returning we restore the context from the frame pointer if
+  // not NULL.  The frame pointer is NULL in the exception handler of
+  // a JS entry frame.
+  __ xor_(esi, Operand(esi));  // Tentatively set context pointer to NULL.
   Label skip;
   __ cmp(ebp, 0);
   __ j(equal, &skip, not_taken);
   __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
   __ bind(&skip);
 
   ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
   __ ret(0);
 }
 
@@ skipping 76 matching lines @@
   // Retry.
   __ bind(&retry);
 }
 
 
 void CEntryStub::GenerateThrowOutOfMemory(MacroAssembler* masm) {
   // Adjust this code if not the case.
   ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
 
   // Drop sp to the top stack handler.
-  ASSERT(StackHandlerConstants::kAddressDisplacement == 0);
   ExternalReference handler_address(Top::k_handler_address);
   __ mov(esp, Operand::StaticVariable(handler_address));
 
   // Unwind the handlers until the ENTRY handler is found.
   Label loop, done;
   __ bind(&loop);
   // Load the type of the current stack handler.
   const int kStateOffset = StackHandlerConstants::kStateOffset;
   __ cmp(Operand(esp, kStateOffset), Immediate(StackHandler::ENTRY));
   __ j(equal, &done);
@@ skipping 251 matching lines @@
 
   // Slow-case: Go through the JavaScript implementation.
   __ bind(&slow);
   __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal