Implement new stacktrace and deoptimization stress testing flags:

runtime/vm/intermediate_language_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 2299 matching lines @@
   return summary;
 }
 
 
 class CheckStackOverflowSlowPath : public SlowPathCode {
  public:
   explicit CheckStackOverflowSlowPath(CheckStackOverflowInstr* instruction)
       : instruction_(instruction) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
+    if (FLAG_use_osr) {
+      uword flags_address = Isolate::Current()->stack_overflow_flags_address();
+      Register temp = instruction_->locs()->temp(0).reg();
+      __ Comment("CheckStackOverflowSlowPathOsr");
+      __ Bind(osr_entry_label());
+      __ LoadImmediate(temp, Immediate(flags_address), PP);
+      __ movq(Address(temp, 0), Immediate(Isolate::kOsrRequest));
+    }
     __ Comment("CheckStackOverflowSlowPath");
     __ Bind(entry_label());
     compiler->SaveLiveRegisters(instruction_->locs());
     // pending_deoptimization_env_ is needed to generate a runtime call that
     // may throw an exception.
     ASSERT(compiler->pending_deoptimization_env_ == NULL);
     Environment* env = compiler->SlowPathEnvironmentFor(instruction_);
     compiler->pending_deoptimization_env_ = env;
     compiler->GenerateRuntimeCall(instruction_->token_pos(),
                                   instruction_->deopt_id(),
                                   kStackOverflowRuntimeEntry,
                                   0,
                                   instruction_->locs());
 
     if (FLAG_use_osr && !compiler->is_optimizing() && instruction_->in_loop()) {
       // In unoptimized code, record loop stack checks as possible OSR entries.
       compiler->AddCurrentDescriptor(PcDescriptors::kOsrEntry,
                                      instruction_->deopt_id(),
                                      0);  // No token position.
     }
     compiler->pending_deoptimization_env_ = NULL;
     compiler->RestoreLiveRegisters(instruction_->locs());
     __ jmp(exit_label());
   }
 
+
+  Label* osr_entry_label() {
+    ASSERT(FLAG_use_osr);
+    return &osr_entry_label_;
+  }
+
  private:
   CheckStackOverflowInstr* instruction_;
+  Label osr_entry_label_;
 };
 
 
 void CheckStackOverflowInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   CheckStackOverflowSlowPath* slow_path = new CheckStackOverflowSlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
   Register temp = locs()->temp(0).reg();
   // Generate stack overflow check.
   __ LoadImmediate(
       temp, Immediate(Isolate::Current()->stack_limit_address()), PP);
   __ cmpq(RSP, Address(temp, 0));
   __ j(BELOW_EQUAL, slow_path->entry_label());
   if (compiler->CanOSRFunction() && in_loop()) {
     // In unoptimized code check the usage counter to trigger OSR at loop
     // stack checks.  Use progressively higher thresholds for more deeply
     // nested loops to attempt to hit outer loops with OSR when possible.
     __ LoadObject(temp, compiler->parsed_function().function(), PP);
     intptr_t threshold =
         FLAG_optimization_counter_threshold * (loop_depth() + 1);
     __ CompareImmediate(FieldAddress(temp, Function::usage_counter_offset()),
                         Immediate(threshold), PP);
-    __ j(GREATER_EQUAL, slow_path->entry_label());
+    __ j(GREATER_EQUAL, slow_path->osr_entry_label());
+  }
+  if (compiler->ForceSlowPathForStackOverflow()) {
+    __ jmp(slow_path->entry_label());
   }
   __ Bind(slow_path->exit_label());
 }
 
 
 static void EmitJavascriptOverflowCheck(FlowGraphCompiler* compiler,
                                         Range* range,
                                         Label* overflow,
                                         Register result) {
   if (!range->IsWithin(-0x20000000000000LL, 0x20000000000000LL)) {
@@ skipping 3049 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(ArgumentCount());  // Discard arguments.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64