[interpreter] Restrict one-shot optimizations to only top-level IIFEs

IIFE`s within a function are not guaranteed to be executed only once.
They can be called multiple times and compiler can inline them.
Do the one-shot optimizations only for IIFE`s from top-level code.

Bug: v8:8072, chromium:886580
Change-Id: I02370681cc3eab270edcc75ee120ca7ad768ed52
Reviewed-on: https://chromium-review.googlesource.com/1231174
Commit-Queue: Chandan Reddy <chandanreddy@google.com>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56024}

src/interpreter/bytecode-generator.cc

@@ -1820,7 +1820,11 @@ bool BytecodeGenerator::ShouldOptimizeAsOneShot() const {
 
   if (loop_depth_ > 0) return false;
 
-  return info()->literal()->is_top_level() || info()->literal()->is_iife();
+  // non-top-level iife is likely to be executed multiple times and so
+  // shouldn`t be optimized as one-shot
+  bool is_top_level_iife = info()->literal()->is_iife() &&
+                           current_scope()->outer_scope()->is_script_scope();
+  return info()->literal()->is_top_level() || is_top_level_iife;
 }
 
 void BytecodeGenerator::BuildClassLiteral(ClassLiteral* expr) {

test/cctest/interpreter/bytecode_expectations/IIFEWithOneshotOpt.golden

@@ -627,3 +627,118 @@ constant pool: [
 handlers: [
 ]
 
+---
+snippet: "
+  
+        var t = 0;
+        function f2() {};
+        if (t == 0) {
+          (function(){
+            l = {};
+            l.a = 3;
+            l.b = 4;
+            f2();
+            return arguments.callee;
+          })();
+        }
+  
+"
+frame size: 6
+parameter count: 1
+bytecode array length: 80
+bytecodes: [
+                B(CreateMappedArguments),
+                B(Star), R(0),
+  /*   79 E> */ B(StackCheck),
+  /*   93 S> */ B(CreateEmptyObjectLiteral),
+  /*   95 E> */ B(StaGlobal), U8(0), U8(0),
+  /*  111 S> */ B(LdaGlobal), U8(0), U8(2),
+                B(Star), R(1),
+                B(LdaSmi), I8(3),
+                B(Star), R(4),
+                B(LdaConstant), U8(1),
+                B(Star), R(3),
+                B(LdaZero),
+                B(Star), R(5),
+                B(Mov), R(1), R(2),
+  /*  115 E> */ B(CallRuntime), U16(Runtime::kSetNamedProperty), R(2), U8(4),
+  /*  130 S> */ B(LdaGlobal), U8(0), U8(2),
+                B(Star), R(1),
+                B(LdaSmi), I8(4),
+                B(Star), R(4),
+                B(LdaConstant), U8(2),
+                B(Star), R(3),
+                B(LdaZero),
+                B(Star), R(5),
+                B(Mov), R(1), R(2),
+  /*  134 E> */ B(CallRuntime), U16(Runtime::kSetNamedProperty), R(2), U8(4),
+  /*  149 S> */ B(LdaUndefined),
+                B(Star), R(2),
+                B(LdaGlobal), U8(3), U8(4),
+                B(Star), R(1),
+  /*  149 E> */ B(CallNoFeedback), R(1), R(2), U8(1),
+  /*  165 S> */ B(LdaConstant), U8(4),
+                B(Star), R(3),
+                B(Mov), R(0), R(2),
+  /*  182 E> */ B(InvokeIntrinsic), U8(Runtime::k_GetProperty), R(2), U8(2),
+  /*  189 S> */ B(Return),
+]
+constant pool: [
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["l"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["a"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["b"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["f2"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["callee"],
+]
+handlers: [
+]
+
+---
+snippet: "
+  
+          function f2() {};
+          function f() {
+            return (function(){
+              l = {};
+              l.a = 3;
+              l.b = 4;
+              f2();
+              return arguments.callee;
+            })();
+          }
+          f();
+  
+"
+frame size: 2
+parameter count: 1
+bytecode array length: 43
+bytecodes: [
+                B(CreateMappedArguments),
+                B(Star), R(0),
+  /*   76 E> */ B(StackCheck),
+  /*   92 S> */ B(CreateEmptyObjectLiteral),
+  /*   94 E> */ B(StaGlobal), U8(0), U8(0),
+  /*  112 S> */ B(LdaGlobal), U8(0), U8(2),
+                B(Star), R(1),
+                B(LdaSmi), I8(3),
+  /*  116 E> */ B(StaNamedProperty), R(1), U8(1), U8(4),
+  /*  133 S> */ B(LdaGlobal), U8(0), U8(2),
+                B(Star), R(1),
+                B(LdaSmi), I8(4),
+  /*  137 E> */ B(StaNamedProperty), R(1), U8(2), U8(6),
+  /*  154 S> */ B(LdaGlobal), U8(3), U8(8),
+                B(Star), R(1),
+  /*  154 E> */ B(CallUndefinedReceiver0), R(1), U8(10),
+  /*  189 S> */ B(LdaNamedProperty), R(0), U8(4), U8(12),
+  /*  196 S> */ B(Return),
+]
+constant pool: [
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["l"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["a"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["b"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["f2"],
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["callee"],
+]
+handlers: [
+]
+

test/cctest/interpreter/test-bytecode-generator.cc

@@ -663,6 +663,33 @@ TEST(IIFEWithOneshotOpt) {
         return arguments.callee;
       })();
     )",
+      R"(
+      var t = 0;
+      function f2() {};
+      if (t == 0) {
+        (function(){
+          l = {};
+          l.a = 3;
+          l.b = 4;
+          f2();
+          return arguments.callee;
+        })();
+      }
+    )",
+      // No one-shot opt for IIFE`s within a function
+      R"(
+        function f2() {};
+        function f() {
+          return (function(){
+            l = {};
+            l.a = 3;
+            l.b = 4;
+            f2();
+            return arguments.callee;
+          })();
+        }
+        f();
+    )",
   };
   CHECK(CompareTexts(BuildActual(printer, snippets),
                      LoadGolden("IIFEWithOneshotOpt.golden")));

test/cctest/test-log.cc

@@ -584,9 +584,9 @@ TEST(LogAll) {
     CHECK(logger.ContainsLine({"api,v8::Script::Run"}));
     CHECK(logger.ContainsLine({"code-creation,LazyCompile,", "testAddFn"}));
     if (i::FLAG_opt && !i::FLAG_always_opt) {
-      CHECK(logger.ContainsLine({"code-deopt,", "eager"}));
+      CHECK(logger.ContainsLine({"code-deopt,", "not a Smi"}));
       if (i::FLAG_enable_one_shot_optimization)
-        CHECK(logger.ContainsLine({"code-deopt,", "soft"}));
+        CHECK(logger.ContainsLine({"code-deopt,", "DeoptimizeNow"}));
       CHECK(logger.ContainsLine({"timer-event-start", "V8.DeoptimizeCode"}));
       CHECK(logger.ContainsLine({"timer-event-end", "V8.DeoptimizeCode"}));
     }