[wasm] Stage tail calls

R=ahaas@chromium.org
CC=ecmziegler@chromium.org

Bug: v8:7431
Change-Id: Ia6303984be4b4f23051fe39a80cdff3143811bb2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2367867
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69518}

src/wasm/wasm-feature-flags.h

@@ -20,11 +20,6 @@
   /* V8 side owner: gdeepti */                                                 \
   V(simd, "SIMD opcodes", false)                                               \
                                                                                \
-  /* Tail call / return call proposal. */                                      \
-  /* https://github.com/webassembly/tail-call */                               \
-  /* V8 side owner: fgm */                                                     \
-  V(return_call, "return call opcodes", false)                                 \
-                                                                               \
   /* No official proposal (yet?). */                                           \
   /* V8 side owner: clemensb */                                                \
   V(compilation_hints, "compilation hints section", false)                     \
@@ -55,6 +50,12 @@
   /* Staged in v7.8. */                                                        \
   V(reftypes, "reference type opcodes", false)                                 \
                                                                                \
+  /* Tail call / return call proposal. */                                      \
+  /* https://github.com/webassembly/tail-call */                               \
+  /* V8 side owner: thibaudm */                                                \
+  /* Staged in v8.7 * */                                                       \
+  V(return_call, "return call opcodes", false)                                 \
+                                                                               \
   /* Threads proposal. */                                                      \
   /* https://github.com/webassembly/threads */                                 \
   /* NOTE: This is enabled via chromium flag on desktop systems since v7.4  */ \

test/fuzzer/wasm-compile.cc

@@ -1726,7 +1726,6 @@ class WasmCompileFuzzer : public WasmExecutionFuzzer {
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   constexpr bool require_valid = true;
   EXPERIMENTAL_FLAG_SCOPE(reftypes);
-  EXPERIMENTAL_FLAG_SCOPE(return_call);
   WasmCompileFuzzer().FuzzWasmModule({data, size}, require_valid);
   return 0;
 }