[regexp] Turn off tier-up when interpret all is on

This CL changes how we handle the case when both --regexp-tier-up and
--regexp-interpret-all flags are on. Previously, we had a CHECK that would
crash if both flags were turned on, now we turn off the tier-up flag and
print a warning message.

Change-Id: I902a59cac9aaf316be05ab2acaee233aa32e023d
Bug: chromium:1002242
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1795353Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Ana Pesko <anapesko@google.com>
Cr-Commit-Position: refs/heads/master@{#63648}

src/init/v8.cc

@@ -90,16 +90,19 @@ void V8::InitializeOncePerProcessImpl() {
     FLAG_expose_wasm = false;
   }
 
+  if (FLAG_regexp_interpret_all && FLAG_regexp_tier_up) {
+    FLAG_regexp_tier_up = false;
+    PrintF(
+        "(WARNING) Turning off the tier-up strategy, because the "
+        "--regexp-interpret-all and --regexp-tier-up flags are incompatible.");
+  }
+
   // The --jitless and --interpreted-frames-native-stack flags are incompatible
   // since the latter requires code generation while the former prohibits code
   // generation.
   CHECK_WITH_MSG(!FLAG_interpreted_frames_native_stack || !FLAG_jitless,
                  "The --jitless and --interpreted-frames-native-stack flags "
-                 "are incompatible");
-
-  CHECK_WITH_MSG(
-      !FLAG_regexp_interpret_all || !FLAG_regexp_tier_up,
-      "The --regexp-interpret-all and --regexp-tier-up flags are incompatible");
+                 "are incompatible.");
 
   base::OS::Initialize(FLAG_hard_abort, FLAG_gc_fake_mmap);