Allow a ParseInfo without a script for %SetCode users

src/compiler.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/compiler.h"
 
 #include <algorithm>
 #include <memory>
 
 #include "src/asmjs/asm-js.h"
@@ skipping 330 matching lines @@
   bool is_unsupported_by_crankshaft_but_turbofanable =
       must_use_ignition_turbo && strcmp(FLAG_turbo_filter, "~~") == 0;
 
   // 3. Explicitly enabled by the command-line filter.
   bool passes_turbo_filter = shared->PassesFilter(FLAG_turbo_filter);
 
   return is_turbofanable_asm || is_unsupported_by_crankshaft_but_turbofanable ||
          passes_turbo_filter;
 }
 
-bool ShouldUseIgnition(CompilationInfo* info) {
-  DCHECK(info->has_shared_info());
-  Handle<SharedFunctionInfo> shared = info->shared_info();
-
+bool ShouldUseIgnition(Handle<SharedFunctionInfo> shared,
+                       bool marked_as_debug) {
   // Code which can't be supported by the old pipeline should use Ignition.
   if (shared->must_use_ignition_turbo()) return true;
 
   // Resumable functions are not supported by {FullCodeGenerator}, suspended
   // activations stored as {JSGeneratorObject} on the heap always assume the
   // underlying code to be based on the bytecode array.
   DCHECK(!IsResumableFunction(shared->kind()));
 
   // Skip Ignition for asm.js functions.
   if (shared->asm_function()) return false;
 
   // Skip Ignition for asm wasm code.
   if (FLAG_validate_asm && shared->HasAsmWasmData()) {
     return false;
   }
 
   // When requesting debug code as a replacement for existing code, we provide
   // the same kind as the existing code (to prevent implicit tier-change).
-  if (info->is_debug() && shared->is_compiled()) {
+  if (marked_as_debug && shared->is_compiled()) {
     return !shared->HasBaselineCode();
   }
 
   // Code destined for TurboFan should be compiled with Ignition first.
   if (UseTurboFan(shared)) return true;
 
   // Only use Ignition for any other function if FLAG_ignition is true.
   return FLAG_ignition;
 }
 
+bool ShouldUseIgnition(CompilationInfo* info) {
+  DCHECK(info->has_shared_info());
+  return ShouldUseIgnition(info->shared_info(), info->is_debug());
+}
+
 bool UseAsmWasm(DeclarationScope* scope, Handle<SharedFunctionInfo> shared_info,
                 bool is_debug) {
   return FLAG_validate_asm && scope->asm_module() &&
          !shared_info->is_asm_wasm_broken() && !is_debug;
 }
 
 bool UseCompilerDispatcher(Compiler::ConcurrencyMode inner_function_mode,
                            CompilerDispatcher* dispatcher,
                            DeclarationScope* scope,
                            Handle<SharedFunctionInfo> shared_info,
@@ skipping 442 matching lines @@
   if (shared->HasBaselineCode()) {
     shared->code()->set_profiler_ticks(0);
   } else if (shared->HasBytecodeArray()) {
     shared->set_profiler_ticks(0);
   }
 
   VMState<COMPILER> state(isolate);
   DCHECK(!isolate->has_pending_exception());
   PostponeInterruptsScope postpone(isolate);
   bool use_turbofan = UseTurboFan(shared) || ignition_osr;
+  bool has_script = shared->script()->IsScript();
+  // BUG(5946): This DCHECK is necessary to make certain that we won't tolerate
+  // the lack of a script without bytecode.
+  DCHECK_IMPLIES(!has_script, ShouldUseIgnition(shared, false));
   std::unique_ptr<CompilationJob> job(
-      use_turbofan ? compiler::Pipeline::NewCompilationJob(function)
+      use_turbofan ? compiler::Pipeline::NewCompilationJob(function, has_script)
                    : new HCompilationJob(function));
   CompilationInfo* info = job->info();
   ParseInfo* parse_info = info->parse_info();
 
   info->SetOptimizingForOsr(osr_ast_id, osr_frame);
 
   // Do not use Crankshaft/TurboFan if we need to be able to set break points.
   if (info->shared_info()->HasDebugInfo()) {
     info->AbortOptimization(kFunctionBeingDebugged);
     return MaybeHandle<Code>();
@@ skipping 201 matching lines @@
     return cached_code;
   }
 
   if (function->shared()->is_compiled() &&
       function->shared()->marked_for_tier_up()) {
     DCHECK(FLAG_mark_shared_functions_for_tier_up);
 
     function->shared()->set_marked_for_tier_up(false);
 
     switch (Compiler::NextCompilationTier(*function)) {
       case Compiler::BASELINE: {

[Leszek Swirski, 2017/02/15 14:58:37]

Can you add a comment here stating that we don't tier up to BASELINE because
GetBaselineCode doesn't support top-level/eval code?

[mvstanton, 2017/02/15 15:18:46]

Yep, done.

-        if (FLAG_trace_opt) {
-          PrintF("[recompiling function ");
-          function->ShortPrint();
-          PrintF(
-              " to baseline eagerly (shared function marked for tier up)]\n");
-        }
-
-        Handle<Code> code;
-        if (GetBaselineCode(function).ToHandle(&code)) {
-          return code;
-        }
         break;
       }
       case Compiler::OPTIMIZED: {
         if (FLAG_trace_opt) {
           PrintF("[optimizing method ");
           function->ShortPrint();
           PrintF(" eagerly (shared function marked for tier up)]\n");
         }
 
         Handle<Code> code;
@@ skipping 822 matching lines @@
   }
 
   if (shared->is_compiled()) {
     // TODO(mvstanton): pass pretenure flag to EnsureLiterals.
     JSFunction::EnsureLiterals(function);
   }
 }
 
 }  // namespace internal
 }  // namespace v8