Allow a ParseInfo without a script for %SetCode users

src/compiler.cc

Index: src/compiler.cc
diff --git a/src/compiler.cc b/src/compiler.cc
index 6292d65a8604c5abd32e46425e13e5eb623b6dd2..e2cd16ae29c27c43caf494fc9d34551d6f016f6e 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -348,10 +348,8 @@ bool UseTurboFan(Handle<SharedFunctionInfo> shared) {
          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;
 
@@ -370,7 +368,7 @@ bool ShouldUseIgnition(CompilationInfo* info) {
 
   // 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();
   }
 
@@ -381,6 +379,11 @@ bool ShouldUseIgnition(CompilationInfo* info) {
   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() &&
@@ -845,8 +848,12 @@ MaybeHandle<Code> GetOptimizedCode(Handle<JSFunction> function,
   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();
@@ -1069,17 +1076,10 @@ MaybeHandle<Code> GetLazyCode(Handle<JSFunction> function) {
 
     switch (Compiler::NextCompilationTier(*function)) {
       case Compiler::BASELINE: {
-        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;
-        }
+        // We don't try to handle baseline here because GetBaselineCode()
+        // doesn't handle top-level code. We aren't supporting
+        // the hybrid pipeline going forward (where Ignition is a first
+        // tier followed by full-code).
         break;
       }
       case Compiler::OPTIMIZED: {