Initial tail call implementation (#2197)

Including parsing, printing, assembling, disassembling.

TODO:

 - interpreting
 - effects
 - finalization and typing
 - fuzzing
 - JS/C API

1 files changed, 6 insertions, 0 deletions

diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index 1d12c2452..01cb1e2a8 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -569,6 +569,9 @@ void FunctionValidator::visitSwitch(Switch* curr) {
 }
 
 void FunctionValidator::visitCall(Call* curr) {
+  shouldBeTrue(!curr->isReturn || getModule()->features.hasTailCall(),
+               curr,
+               "return_call requires tail calls to be enabled");
   if (!info.validateGlobally) {
     return;
   }
@@ -593,6 +596,9 @@ void FunctionValidator::visitCall(Call* curr) {
 }
 
 void FunctionValidator::visitCallIndirect(CallIndirect* curr) {
+  shouldBeTrue(!curr->isReturn || getModule()->features.hasTailCall(),
+               curr,
+               "return_call_indirect requires tail calls to be enabled");
   if (!info.validateGlobally) {
     return;
   }