[turbofan] Fix crash with --trace-turbo-inlining

When the flag is on and some of the functions don't have bytecode,
we should gracefully print "no bytecode" instead of crashing.

Bug: chromium:983267
Change-Id: Id4e3385cd871a2dd5bead38c29a41b38319cc8d3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1731003Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63031}

src/compiler/js-inlining-heuristic.cc

@@ -736,12 +736,16 @@ void JSInliningHeuristic::PrintCandidates() {
        << candidate.node->op()->mnemonic()
        << ", frequency: " << candidate.frequency << std::endl;
     for (int i = 0; i < candidate.num_functions; ++i) {
+      if (candidate.bytecode[i].has_value()) {
+        PrintF("  - size:%d,", candidate.bytecode[i].value().length());
+      } else {
+        PrintF("  - no bytecode,");
+      }
       SharedFunctionInfoRef shared =
           candidate.functions[i].has_value()
               ? candidate.functions[i].value().shared()
               : candidate.shared_info.value();
-      PrintF("  - size:%d, name: %s\n", candidate.bytecode[i].value().length(),
-             shared.object()->DebugName().ToCString().get());
+      PrintF(" name: %s\n", shared.object()->DebugName().ToCString().get());
     }
   }
 }

test/mjsunit/regress/regress-inlining-printing.js

+// Copyright 2019 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.
+
+// Flags: --allow-natives-syntax --trace-turbo-inlining
+// Flags: --max-inlined-bytecode-size-small=0
+
+function f() {}
+function g() {}
+function h() {}
+
+function test(n) {
+  h;
+  (n == 0 ? f : (n > 0 ? g : h))();
+}
+
+%EnsureFeedbackVectorForFunction(f);
+%EnsureFeedbackVectorForFunction(g);
+
+%PrepareFunctionForOptimization(test);
+test(0);
+test(1);
+%OptimizeFunctionOnNextCall(test);
+test(0);