BTOS opcode; decrease gas usage for HASHSU

Author: SpyCheese

common/global-version.h

@@ -19,6 +19,6 @@
 namespace ton {
 
 // See doc/GlobalVersions.md
-constexpr int SUPPORTED_VERSION = 11;
+constexpr int SUPPORTED_VERSION = 12;
 
 }

crypto/fift/lib/Asm.fif

@@ -697,6 +697,7 @@ x{CF3F} @Defop BCHKBITREFSQ
 x{CF40} @Defop STZEROES
 x{CF41} @Defop STONES
 x{CF42} @Defop STSAME
+x{CF50} @Defop BTOS
 { tuck sbitrefs swap 22 + swap @havebitrefs not
   { swap PUSHSLICE STSLICER }
   { over sbitrefs 2dup 57 3 2x<=

crypto/vm/cellops.cpp

@@ -764,6 +764,15 @@ int exec_store_same(VmState* st, const char* name, int val) {
   return 0;
 }
 
+int exec_builder_to_slice(VmState* st) {
+  Stack& stack = st->get_stack();
+  VM_LOG(st) << "execute BTOS";
+  stack.check_underflow(1);
+  Ref<Cell> cell = stack.pop_builder().write().finalize_novm();
+  stack.push_cellslice(Ref<CellSlice>{true, NoVm(), cell});
+  return 0;
+}
+
 int exec_store_const_slice(VmState* st, CellSlice& cs, unsigned args, int pfx_bits) {
   unsigned refs = (args >> 3) & 3;
   unsigned data_bits = (args & 7) * 8 + 2;
@@ -866,6 +875,7 @@ void register_cell_serialize_ops(OpcodeTable& cp0) {
       .insert(OpcodeInstr::mksimple(0xcf40, 16, "STZEROES", std::bind(exec_store_same, _1, "STZEROES", 0)))
       .insert(OpcodeInstr::mksimple(0xcf41, 16, "STONES", std::bind(exec_store_same, _1, "STONES", 1)))
       .insert(OpcodeInstr::mksimple(0xcf42, 16, "STSAME", std::bind(exec_store_same, _1, "STSAME", -1)))
+      .insert(OpcodeInstr::mksimple(0xcf50, 16, "BTOS", exec_builder_to_slice)->require_version(12))
       .insert(OpcodeInstr::mkext(0xcf80 >> 7, 9, 5, dump_store_const_slice, exec_store_const_slice,
                                  compute_len_store_const_slice));
 }

crypto/vm/tonops.cpp

@@ -618,10 +618,13 @@ int exec_compute_hash(VmState* st, int mode) {
     hash = cell->get_hash().as_array();
   } else {
     auto cs = stack.pop_cellslice();
-    vm::CellBuilder cb;
+    CellBuilder cb;
     CHECK(cb.append_cellslice_bool(std::move(cs)));
-    // TODO: use cb.get_hash() instead
-    hash = cb.finalize()->get_hash().as_array();
+    if (st->get_global_version() >= 12) {
+      hash = cb.finalize_novm()->get_hash().as_array();
+    } else {
+      hash = cb.finalize()->get_hash().as_array();
+    }
   }
   td::RefInt256 res{true};
   CHECK(res.write().import_bytes(hash.data(), hash.size(), false));

doc/GlobalVersions.md

@@ -144,6 +144,7 @@ Example: if the last masterchain block seqno is `19071` then the list contains b
 - Fix recursive jump to continuations with non-null control data.
 
 ## Version 10
+__Enabled in mainnet on 2025-05-07__
 
 ### Extra currencies
 - Internal messages cannot carry more than 2 different extra currencies. The limit can be changed in size limits config (`ConfigParam 43`).
@@ -194,6 +195,7 @@ Reserve modes `+1`, `+4` and `+8` ("reserve all except", "add original balance"
 - Exceeding state limits in transaction now reverts `end_lt` back to `start_lt + 1` and collects action fines.
 
 ## Version 11
+__Enabled in mainnet on 2025-07-05__
 
 ### c7 tuple
 **c7** tuple extended from 17 to 18 elements:
@@ -225,4 +227,12 @@ This is required to help computing storage stats in the future, after collator-v
 
 ### Other changes
 - Fix returning `null` as `c4` and `c5` (when VM state is not committed) in `RUNVM`.
-- In new internal messages `ihr_disabled` is automatically set to `1`, `ihr_fee` is always zero.
+- In new internal messages `ihr_disabled` is automatically set to `1`, `ihr_fee` is always zero.
+
+## Version 12
+
+### New TVM instructions
+- `BTOS` (`b - s`) - same as `ENDC CTOS`, but without gas cost for cell creation and loading. Gas cost: `26`.
+
+### Other TVM changes
+- `HASHSU` (`s - hash`) now does not spend gas for cell creation. Gas cost: `26`.