Consume gas in VmState::jump_to

Author: SpyCheese

crypto/vm/vm.h

@@ -118,6 +118,7 @@ class VmState final : public VmStateInterface {
     stack_entry_gas_price = 1,
     runvm_gas_price = 40,
     hash_ext_entry_gas_price = 1,
+    free_nested_cont_jump = 8,
 
     rist255_mul_gas_price = 2000,
     rist255_mulbase_gas_price = 750,
@@ -366,14 +367,18 @@ class VmState final : public VmStateInterface {
     return cond ? c1_envelope(std::move(cont), save) : std::move(cont);
   }
   void c1_save_set(bool save = true);
-  void fatal(void) const {
+  void fatal() const {
     throw VmFatal{};
   }
   int jump_to(Ref<Continuation> cont) {
-    int res = 0;
+    int res = 0, cnt = 0;
     while (cont.not_null()) {
+      cnt++;
       cont = cont->is_unique() ? cont.unique_write().jump_w(this, res) : cont->jump(this, res);
     }
+    if (global_version >= 9 && cnt > free_nested_cont_jump) {
+      consume_gas(cnt - free_nested_cont_jump);
+    }
     return res;
   }
   static Ref<CellSlice> convert_code_cell(Ref<Cell> code_cell);

doc/GlobalVersions.md

@@ -114,4 +114,5 @@ Operations for working with Merkle proofs, where cells can have non-zero level a
 ## Version 9
 
 - Fix `RAWRESERVE` action with flag `4` (use original balance of the account) by explicitly setting `original_balance` to `balance - msg_balance_remaining`.
-  - Previously it did not work if storage fee was greater than the original balance.
+  - Previously it did not work if storage fee was greater than the original balance.
+- Jumps to nested continuations of depth more than 8 consume 1 gas for eact subsequent continuation (this does not affect most of TVM code).