Switch full-codegen from StackHandlers to handler table.

src/isolate.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 <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
 
 #include "src/v8.h"
@@ skipping 990 matching lines @@
 
 Object* Isolate::ReThrow(Object* exception) {
   DCHECK(!has_pending_exception());
 
   // Set the exception being re-thrown.
   set_pending_exception(exception);
   return heap()->exception();
 }
 
 
-// TODO(turbofan): Make sure table is sorted and use binary search.
-static int LookupInHandlerTable(Code* code, int pc_offset) {
-  FixedArray* handler_table = code->handler_table();
-  for (int i = 0; i < handler_table->length(); i += 2) {
-    int return_offset = Smi::cast(handler_table->get(i))->value();
-    int handler_offset = Smi::cast(handler_table->get(i + 1))->value();
-    if (pc_offset == return_offset) return handler_offset;
-  }
-  return -1;
-}
-
-
 Object* Isolate::FindHandler() {
   Object* exception = pending_exception();
 
   Code* code = nullptr;
   Context* context = nullptr;
   intptr_t offset = 0;
   Address handler_sp = nullptr;
   Address handler_fp = nullptr;
 
   // Special handling of termination exceptions, uncatchable by JavaScript code,
   // we unwind the handlers until the top ENTRY handler is found.
   bool catchable_by_js = is_catchable_by_javascript(exception);
 
   // Compute handler and stack unwinding information by performing a full walk
   // over the stack and dispatching according to the frame type.
   for (StackFrameIterator iter(this); !iter.done(); iter.Advance()) {
     StackFrame* frame = iter.frame();
 
     // For JSEntryStub frames we always have a handler.
     if (frame->is_entry() || frame->is_entry_construct()) {
       StackHandler* handler = frame->top_handler();
-      DCHECK_EQ(0, handler->index());
 
       // Restore the next handler.
       thread_local_top()->handler_ = handler->next()->address();
 
       // Gather information from the handler.
       code = frame->LookupCode();
       handler_sp = handler->address() + StackHandlerConstants::kSize;
       offset = Smi::cast(code->handler_table()->get(0))->value();
       break;
     }
 
-    // For JavaScript frames which have a handler, we use the handler.
-    if (frame->is_java_script() && catchable_by_js && frame->HasHandler()) {
-      StackHandler* handler = frame->top_handler();
-
-      // Restore the next handler.
-      thread_local_top()->handler_ = handler->next()->address();
-
-      // Gather information from the handler.
-      code = frame->LookupCode();
-      context = handler->context();
-      offset = Smi::cast(code->handler_table()->get(handler->index()))->value();
-      handler_sp = handler->address() + StackHandlerConstants::kSize;
-      handler_fp = frame->fp();
-      break;
-    }
-
     // For optimized frames we perform a lookup in the handler table.
     if (frame->is_optimized() && catchable_by_js) {
-      Code* frame_code = frame->LookupCode();
-      DCHECK(frame_code->is_optimized_code());
-      int pc_offset = static_cast<int>(frame->pc() - frame_code->entry());
-      int handler_offset = LookupInHandlerTable(frame_code, pc_offset);
-      if (handler_offset < 0) continue;
+      OptimizedFrame* js_frame = static_cast<OptimizedFrame*>(frame);
+      int stack_slots = 0;  // Will contain stack slot count of frame.
+      offset = js_frame->LookupExceptionHandlerInTable(&stack_slots);
+      if (offset < 0) continue;
 
       // Compute the stack pointer from the frame pointer. This ensures that
       // argument slots on the stack are dropped as returning would.
       Address return_sp = frame->fp() -
                           StandardFrameConstants::kFixedFrameSizeFromFp -
-                          frame_code->stack_slots() * kPointerSize;
+                          stack_slots * kPointerSize;
 
       // Gather information from the frame.
-      code = frame_code;
-      offset = handler_offset;
+      code = frame->LookupCode();
       handler_sp = return_sp;
       handler_fp = frame->fp();
       break;
+    }
+
+    // For JavaScript frames we perform a range lookup in the handler table.
+    if (frame->is_java_script() && catchable_by_js) {
+      JavaScriptFrame* js_frame = static_cast<JavaScriptFrame*>(frame);
+      int stack_slots = 0;  // Will contain operand stack depth of handler.
+      offset = js_frame->LookupExceptionHandlerInTable(&stack_slots);
+      if (offset < 0) continue;
+
+      // Compute the stack pointer from the frame pointer. This ensures that
+      // operand stack slots are dropped for nested statements. Also restore
+      // correct context for the handler which is pushed within the try-block.
+      Address return_sp = frame->fp() -
+                          StandardFrameConstants::kFixedFrameSizeFromFp -
+                          stack_slots * kPointerSize;
+      STATIC_ASSERT(TryBlockConstant::kElementCount == 1);
+      context = Context::cast(Memory::Object_at(return_sp - kPointerSize));
+
+      // Gather information from the frame.
+      code = frame->LookupCode();
+      handler_sp = return_sp;
+      handler_fp = frame->fp();
+      break;
     }
   }
 
   // Handler must exist.
   CHECK(code != nullptr);
 
   // Store information to be consumed by the CEntryStub.
   thread_local_top()->pending_handler_context_ = context;
   thread_local_top()->pending_handler_code_ = code;
   thread_local_top()->pending_handler_offset_ = offset;
   thread_local_top()->pending_handler_fp_ = handler_fp;
   thread_local_top()->pending_handler_sp_ = handler_sp;
 
   // Return and clear pending exception.
   clear_pending_exception();
   return exception;
 }
 
 
 // TODO(mstarzinger): We shouldn't need the exception object here.
 bool Isolate::PredictWhetherExceptionIsCaught(Object* exception) {
   if (IsExternalHandlerOnTop(exception)) return true;
 
-  // Search for a JavaScript handler by performing a full walk over the stack
-  // and dispatching according to the frame type.
-  for (StackFrameIterator iter(this); !iter.done(); iter.Advance()) {
-    StackFrame* frame = iter.frame();
-
-    // For JavaScript frames which have a handler, we use the handler.
-    if (frame->is_java_script() && frame->HasHandler()) {
-      return true;
-    }
-
-    // For optimized frames we perform a lookup in the handler table.
-    if (frame->is_optimized()) {
-      Code* frame_code = frame->LookupCode();
-      DCHECK(frame_code->is_optimized_code());
-      int pc_offset = static_cast<int>(frame->pc() - frame_code->entry());
-      int handler_offset = LookupInHandlerTable(frame_code, pc_offset);
-      if (handler_offset < 0) continue;
-      return true;
-    }
+  // Search for a JavaScript handler by performing a full walk over the stack.
+  for (JavaScriptFrameIterator iter(this); !iter.done(); iter.Advance()) {
+    JavaScriptFrame* frame = iter.frame();
+    int stack_slots = 0;  // The computed stack slot count is not used.
+    if (frame->LookupExceptionHandlerInTable(&stack_slots) > 0) return true;
   }
 
   // Handler not found.
   return false;
 }
 
 
 Object* Isolate::ThrowIllegalOperation() {
   if (FLAG_stack_trace_on_illegal) PrintStack(stdout);
   return Throw(heap()->illegal_access_string());
@@ skipping 1478 matching lines @@
   if (prev_ && prev_->Intercept(flag)) return true;
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 } }  // namespace v8::internal