firedancer-io · topointon-jump · Dec 15, 2025
diff --git a/src/flamenco/features/fd_features_generated.c b/src/flamenco/features/fd_features_generated.c
@@ -1703,6 +1703,12 @@ fd_feature_id_t const ids[] = {
     .name                      = "provide_instruction_data_offset_in_vm_r2",
     .cleaned_up                = {UINT_MAX, UINT_MAX, UINT_MAX} },
 
+  { .index                     = offsetof(fd_features_t, static_instruction_limit)>>3,
+    .id                        = {"\x4b\x3e\xa0\x91\xa9\xb6\xb5\xda\x05\x3a\x32\x6f\x7c\x18\xd9\x0d\x60\x87\x99\x76\xfb\xc6\x6f\x18\xc1\xfa\x37\x38\x94\x41\xc1\xf9"},
+                                 /* 64ixypL1HPu8WtJhNSMb9mSgfFaJvsANuRkTbHyuLfnx */
+    .name                      = "static_instruction_limit",
+    .cleaned_up                = {UINT_MAX, UINT_MAX, UINT_MAX} },
+
   { .index = ULONG_MAX }
 };
 /* TODO replace this with fd_map_perfect */
@@ -1958,6 +1964,7 @@ fd_feature_id_query( ulong prefix ) {
   case 0x8c7bee4552d93e0c: return &ids[ 246 ];
   case 0x866094bbfe00a7c6: return &ids[ 247 ];
   case 0x7c4802b8ba3fa849: return &ids[ 248 ];
+  case 0xdab5b6a991a03e4b: return &ids[ 249 ];
   default: break;
   }
   return NULL;
@@ -2212,4 +2219,5 @@ FD_STATIC_ASSERT( offsetof( fd_features_t, fix_alt_bn128_pairing_length_check
 FD_STATIC_ASSERT( offsetof( fd_features_t, poseidon_enforce_padding                                )>>3==246UL, layout );
 FD_STATIC_ASSERT( offsetof( fd_features_t, relax_intrabatch_account_locks                          )>>3==247UL, layout );
 FD_STATIC_ASSERT( offsetof( fd_features_t, provide_instruction_data_offset_in_vm_r2                )>>3==248UL, layout );
+FD_STATIC_ASSERT( offsetof( fd_features_t, static_instruction_limit                                )>>3==249UL, layout );
 FD_STATIC_ASSERT( sizeof( fd_features_t )>>3==FD_FEATURE_ID_CNT, layout );
diff --git a/src/flamenco/features/fd_features_generated.h b/src/flamenco/features/fd_features_generated.h
@@ -8,10 +8,10 @@
 #endif
 
 /* FEATURE_ID_CNT is the number of features in ids */
-#define FD_FEATURE_ID_CNT (249UL)
+#define FD_FEATURE_ID_CNT (250UL)
 
 /* Feature set ID calculated from all feature names */
-#define FD_FEATURE_SET_ID (4167120720U)
+#define FD_FEATURE_SET_ID (3098242546U)
 
 union fd_features {
   ulong f[ FD_FEATURE_ID_CNT ];
@@ -265,5 +265,6 @@ union fd_features {
     /* 0x8c7bee4552d93e0c */ ulong poseidon_enforce_padding;
     /* 0x866094bbfe00a7c6 */ ulong relax_intrabatch_account_locks;
     /* 0x7c4802b8ba3fa849 */ ulong provide_instruction_data_offset_in_vm_r2;
+    /* 0xdab5b6a991a03e4b */ ulong static_instruction_limit;
   };
 };
diff --git a/src/flamenco/features/feature_map.json b/src/flamenco/features/feature_map.json
@@ -247,5 +247,6 @@
   {"name":"fix_alt_bn128_pairing_length_check","pubkey":"bnYzodLwmybj7e1HAe98yZrdJTd7we69eMMLgCXqKZm"},
   {"name":"poseidon_enforce_padding","pubkey":"poUdAqRXXsNmfqAZ6UqpjbeYgwBygbfQLEvWSqVhSnb"},
   {"name":"relax_intrabatch_account_locks","pubkey":"ENTRYnPAoT5Swwx73YDGzMp3XnNH1kxacyvLosRHza1i"},
-  {"name":"provide_instruction_data_offset_in_vm_r2","pubkey":"5xXZc66h4UdB6Yq7FzdBxBiRAFMMScMLwHxk2QZDaNZL"}
+  {"name":"provide_instruction_data_offset_in_vm_r2","pubkey":"5xXZc66h4UdB6Yq7FzdBxBiRAFMMScMLwHxk2QZDaNZL"},
+  {"name":"static_instruction_limit","pubkey":"64ixypL1HPu8WtJhNSMb9mSgfFaJvsANuRkTbHyuLfnx"}
 ]
diff --git a/src/flamenco/runtime/Local.mk b/src/flamenco/runtime/Local.mk
@@ -55,6 +55,8 @@ ifdef FD_HAS_HOSTED
 ifdef FD_HAS_SECP256K1
 $(call make-unit-test,test_bank,test_bank,fd_flamenco fd_funk fd_ballet fd_util)
 $(call run-unit-test,test_bank,)
+$(call make-unit-test,test_static_instruction_limit,test_static_instruction_limit,fd_flamenco fd_funk fd_ballet fd_util)
+$(call run-unit-test,test_static_instruction_limit,)
 endif
 endif
 

diff --git a/src/flamenco/runtime/fd_executor.c b/src/flamenco/runtime/fd_executor.c
@@ -401,11 +401,18 @@ fd_executor_check_transactions( fd_runtime_t *      runtime,
 
    https://github.com/anza-xyz/agave/blob/v2.3.1/runtime/src/bank.rs#L5725-L5753 */
 int
-fd_executor_verify_transaction( fd_bank_t *         bank,
+fd_executor_verify_transaction( fd_bank_t const *   bank,
                                 fd_txn_in_t const * txn_in,
                                 fd_txn_out_t *      txn_out ) {
   int err = FD_RUNTIME_EXECUTE_SUCCESS;
 
+  /* SIMD-0160: enforce static limit on number of instructions.
+     https://github.com/anza-xyz/agave/blob/v3.1.4/runtime/src/bank.rs#L4710-L4716 */
+  if( FD_UNLIKELY( FD_FEATURE_ACTIVE_BANK( bank, static_instruction_limit ) &&
+                   TXN( txn_in->txn )->instr_cnt > FD_MAX_INSTRUCTION_TRACE_LENGTH ) ) {
+    return FD_RUNTIME_TXN_ERR_SANITIZE_FAILURE;
+  }
+
   /* https://github.com/anza-xyz/agave/blob/v2.2.13/svm/src/transaction_processor.rs#L566-L569 */
   err = fd_executor_compute_budget_program_execute_instructions( bank, txn_in, txn_out );
   if( FD_UNLIKELY( err ) ) return err;

diff --git a/src/flamenco/runtime/fd_executor.h b/src/flamenco/runtime/fd_executor.h
@@ -40,7 +40,7 @@ uchar
 fd_executor_pubkey_is_bpf_loader( fd_pubkey_t const * pubkey );
 
 int
-fd_executor_verify_transaction( fd_bank_t *         bank,
+fd_executor_verify_transaction( fd_bank_t const *   bank,
                                 fd_txn_in_t const * txn_in,
                                 fd_txn_out_t *      txn_out );
 

diff --git a/src/flamenco/runtime/program/fd_builtin_programs.c b/src/flamenco/runtime/program/fd_builtin_programs.c
@@ -336,7 +336,7 @@ fd_num_precompiles( void ) {
 }
 
 uchar
-fd_is_migrating_builtin_program( fd_bank_t *         bank,
+fd_is_migrating_builtin_program( fd_bank_t const *   bank,
                                  fd_pubkey_t const * pubkey,
                                  uchar *             migrated_yet ) {
   *migrated_yet = 0;

diff --git a/src/flamenco/runtime/program/fd_builtin_programs.h b/src/flamenco/runtime/program/fd_builtin_programs.h
@@ -95,7 +95,7 @@ fd_num_stateless_builtins( void );
     |      1       |        1          | Program is a migrating builtin program id, AND has been migrated to BPF  |
 */
 uchar
-fd_is_migrating_builtin_program( fd_bank_t *         bank,
+fd_is_migrating_builtin_program( fd_bank_t const *   bank,
                                  fd_pubkey_t const * pubkey,
                                  uchar *             migrated_yet );
 

diff --git a/src/flamenco/runtime/program/fd_compute_budget_program.c b/src/flamenco/runtime/program/fd_compute_budget_program.c
@@ -14,7 +14,7 @@
 #define MAX_BUILTIN_ALLOCATION_COMPUTE_UNIT_LIMIT (3000UL)
 
 FD_FN_PURE static inline uchar
-get_program_kind( fd_bank_t *            bank,
+get_program_kind( fd_bank_t const *      bank,
                   fd_txn_in_t const *    txn_in,
                   fd_txn_instr_t const * instr ) {
   fd_acct_addr_t const * txn_accs       = fd_txn_get_acct_addrs( TXN( txn_in->txn ), txn_in->txn->payload );
@@ -114,7 +114,7 @@ fd_sanitize_compute_unit_limits( fd_txn_out_t * txn_out ) {
 
    https://github.com/anza-xyz/agave/blob/v2.3.1/compute-budget-instruction/src/compute_budget_instruction_details.rs#L54-L99 */
 int
-fd_executor_compute_budget_program_execute_instructions( fd_bank_t *         bank,
+fd_executor_compute_budget_program_execute_instructions( fd_bank_t const *   bank,
                                                          fd_txn_in_t const * txn_in,
                                                          fd_txn_out_t *      txn_out ) {
   fd_compute_budget_details_t * details = &txn_out->details.compute_budget;

diff --git a/src/flamenco/runtime/program/fd_compute_budget_program.h b/src/flamenco/runtime/program/fd_compute_budget_program.h
@@ -30,7 +30,7 @@ int
 fd_sanitize_compute_unit_limits( fd_txn_out_t * txn_out );
 
 int
-fd_executor_compute_budget_program_execute_instructions( fd_bank_t *         bank,
+fd_executor_compute_budget_program_execute_instructions( fd_bank_t const *   bank,
                                                          fd_txn_in_t const * txn_in,
                                                          fd_txn_out_t *      txn_out );
 

diff --git a/src/flamenco/runtime/test_static_instruction_limit.c b/src/flamenco/runtime/test_static_instruction_limit.c
@@ -0,0 +1,125 @@
+/* Test for SIMD-0160 static_instruction_limit */
+
+#include "fd_executor.h"
+#include "fd_bank.h"
+#include "fd_runtime.h"
+#include "fd_runtime_err.h"
+#include "../features/fd_features.h"
+
+static void
+init_bank( fd_bank_t * bank ) {
+  memset( bank, 0, sizeof(fd_bank_t) );
+  fd_bank_slot_set( bank, 1UL );
+}
+
+static void
+init_txn_with_instr_cnt( fd_txn_p_t * txn_p,
+                         ushort       instr_cnt ) {
+  fd_txn_t * txn = TXN( txn_p );
+
+  txn->transaction_version = FD_TXN_V0;
+  txn->instr_cnt           = instr_cnt;
+
+  for( ushort i=0; i<instr_cnt; i++ ) {
+    txn->instr[i].program_id = 0;
+    txn->instr[i].acct_cnt   = 0;
+    txn->instr[i].data_sz    = 0;
+    txn->instr[i].acct_off   = 0;
+    txn->instr[i].data_off   = 0;
+  }
+}
+
+static void
+activate_static_instruction_limit( fd_bank_t * bank ) {
+  fd_bank_features_modify( bank )->static_instruction_limit = 0UL;
+}
+
+static void
+deactivate_static_instruction_limit( fd_bank_t * bank ) {
+  fd_bank_features_modify( bank )->static_instruction_limit = FD_FEATURE_DISABLED;
+}
+
+static void
+test_static_instruction_limit_deactivated( fd_bank_t * bank ) {
+  fd_txn_p_t   txn_p[1]   = {0};
+  fd_txn_out_t txn_out[1] = {0};
+
+  init_bank( bank );
+  deactivate_static_instruction_limit( bank );
+  init_txn_with_instr_cnt( txn_p, 65 );
+
+  fd_txn_in_t txn_in = { .txn = txn_p };
+
+  FD_TEST( fd_executor_verify_transaction( bank, &txn_in, txn_out )==FD_RUNTIME_EXECUTE_SUCCESS );
+}
+
+static void
+test_static_instruction_limit_exceeded( fd_bank_t * bank ) {
+  fd_txn_p_t   txn_p[1]   = {0};
+  fd_txn_out_t txn_out[1] = {0};
+
+  init_bank( bank );
+  activate_static_instruction_limit( bank );
+  init_txn_with_instr_cnt( txn_p, 65 );
+
+  fd_txn_in_t txn_in = { .txn = txn_p };
+
+  FD_TEST( fd_executor_verify_transaction( bank, &txn_in, txn_out )==FD_RUNTIME_TXN_ERR_SANITIZE_FAILURE );
+}
+
+static void
+test_static_instruction_limit_at_limit( fd_bank_t * bank ) {
+  fd_txn_p_t   txn_p[1]   = {0};
+  fd_txn_out_t txn_out[1] = {0};
+
+  init_bank( bank );
+  activate_static_instruction_limit( bank );
+  init_txn_with_instr_cnt( txn_p, 64 );
+
+  fd_txn_in_t txn_in = { .txn = txn_p };
+
+  FD_TEST( fd_executor_verify_transaction( bank, &txn_in, txn_out )==FD_RUNTIME_EXECUTE_SUCCESS );
+}
+
+static void
+test_static_instruction_limit_under_limit( fd_bank_t * bank ) {
+  fd_txn_p_t   txn_p[1]   = {0};
+  fd_txn_out_t txn_out[1] = {0};
+
+  init_bank( bank );
+  activate_static_instruction_limit( bank );
+  init_txn_with_instr_cnt( txn_p, 1 );
+
+  fd_txn_in_t txn_in = { .txn = txn_p };
+
+  FD_TEST( fd_executor_verify_transaction( bank, &txn_in, txn_out )==FD_RUNTIME_EXECUTE_SUCCESS );
+}
+
+int
+main( int     argc,
+      char ** argv ) {
+  fd_boot( &argc, &argv );
+
+  char *      _page_sz = "gigantic";
+  ulong       numa_idx = fd_shmem_numa_idx( 0 );
+  fd_wksp_t * wksp     = fd_wksp_new_anonymous( fd_cstr_to_shmem_page_sz( _page_sz ),
+                                                1UL,
+                                                fd_shmem_cpu_idx( numa_idx ),
+                                                "wksp",
+                                                0UL );
+  FD_TEST( wksp );
+
+  fd_bank_t * bank = fd_wksp_alloc_laddr( wksp, alignof(fd_bank_t), sizeof(fd_bank_t), 1UL );
+  FD_TEST( bank );
+
+  test_static_instruction_limit_deactivated( bank );
+  test_static_instruction_limit_exceeded( bank );
+  test_static_instruction_limit_at_limit( bank );
+  test_static_instruction_limit_under_limit( bank );
+
+  fd_wksp_delete_anonymous( wksp );
+
+  FD_LOG_NOTICE(( "pass" ));
+  fd_halt();
+  return 0;
+}