wip implementation of get_epoch_stake syscall

src/flamenco/features/fd_features_generated.c

@@ -1229,6 +1229,12 @@ fd_feature_id_t const ids[] = {
     .name       = "partitioned_epoch_rewards_superfeature",
     .cleaned_up = {UINT_MAX, UINT_MAX, UINT_MAX} },
 
+  { .index      = offsetof(fd_features_t, enable_get_epoch_stake_syscall)>>3,
+    .id         = {"\x64\x88\xa2\xd0\x5a\xcc\xbb\xae\xa0\x4e\xa8\xaf\xeb\x15\xfb\x71\xa7\x5b\x27\x71\x96\x6c\x2f\x05\x0d\xfe\xf3\x44\xbb\x07\x3b\x21"},
+                  /* 7mScTYkJXsbdrcwTQRs7oeCSXoJm4WjzBsRyf8bCU3Np */
+    .name       = "enable_get_epoch_stake_syscall",
+    .cleaned_up = {UINT_MAX, UINT_MAX, UINT_MAX} },
+
   { .index = ULONG_MAX }
 };
 
@@ -1443,6 +1449,7 @@ fd_feature_id_query( ulong prefix ) {
   case 0x0b9047b5bb9ef961: return &ids[ 200 ];
   case 0xa5a66405d0ab6309: return &ids[ 201 ];
   case 0x81fcbfa0d0f6b105: return &ids[ 202 ];
+  case 0xaebbcc5ad0a28864: return &ids[ 203 ];
   default: break;
   }
 
@@ -1654,5 +1661,6 @@ FD_STATIC_ASSERT( offsetof( fd_features_t, zk_elgamal_proof_program_enabled
 FD_STATIC_ASSERT( offsetof( fd_features_t, move_stake_and_move_lamports_ixs                        )>>3==200UL, layout );
 FD_STATIC_ASSERT( offsetof( fd_features_t, deprecate_legacy_vote_ixs                               )>>3==201UL, layout );
 FD_STATIC_ASSERT( offsetof( fd_features_t, partitioned_epoch_rewards_superfeature                  )>>3==202UL, layout );
+FD_STATIC_ASSERT( offsetof( fd_features_t, enable_get_epoch_stake_syscall                          )>>3==203UL, layout );
 
 FD_STATIC_ASSERT( sizeof( fd_features_t )>>3==FD_FEATURE_ID_CNT, layout );

src/flamenco/features/fd_features_generated.h

@@ -6,7 +6,7 @@
 
 /* FEATURE_ID_CNT is the number of features in ids */
 
-#define FD_FEATURE_ID_CNT (203UL)
+#define FD_FEATURE_ID_CNT (204UL)
 
 union fd_features {
 
@@ -216,6 +216,7 @@ union fd_features {
     /* 0x0b9047b5bb9ef961 */ ulong move_stake_and_move_lamports_ixs;
     /* 0xa5a66405d0ab6309 */ ulong deprecate_legacy_vote_ixs;
     /* 0x81fcbfa0d0f6b105 */ ulong partitioned_epoch_rewards_superfeature;
+    /* 0xaebbcc5ad0a28864 */ ulong enable_get_epoch_stake_syscall;
   };
 
 };

src/flamenco/features/feature_map.json

@@ -201,5 +201,6 @@
   {"name":"zk_elgamal_proof_program_enabled","pubkey":"zkhiy5oLowR7HY4zogXjCjeMXyruLqBwSWH21qcFtnv"},
   {"name":"move_stake_and_move_lamports_ixs","pubkey":"7bTK6Jis8Xpfrs8ZoUfiMDPazTcdPcTWheZFJTA5Z6X4"},
   {"name":"deprecate_legacy_vote_ixs","pubkey":"depVvnQ2UysGrhwdiwU42tCadZL8GcBb1i2GYhMopQv"},
-  {"name":"partitioned_epoch_rewards_superfeature","pubkey":"PERzQrt5gBD1XEe2c9XdFWqwgHY3mr7cYWbm5V772V8"}
+  {"name":"partitioned_epoch_rewards_superfeature","pubkey":"PERzQrt5gBD1XEe2c9XdFWqwgHY3mr7cYWbm5V772V8"},
+  {"name":"enable_get_epoch_stake_syscall","pubkey":"7mScTYkJXsbdrcwTQRs7oeCSXoJm4WjzBsRyf8bCU3Np"}
 ]

src/flamenco/runtime/fd_runtime.c

@@ -295,7 +295,7 @@ fd_runtime_init_bank_from_genesis( fd_exec_slot_ctx_t *  slot_ctx,
       .stake_delegations_pool = sacc_pool,
       .stake_delegations_root = sacc_root,
       .epoch = 0,
-      .unused = 0,
+      .total_stake = 0,
       .vote_accounts = (fd_vote_accounts_t){
           .vote_accounts_pool = vacc_pool,
           .vote_accounts_root = vacc_root},
@@ -3931,6 +3931,7 @@ void fd_update_stake_delegations(fd_exec_slot_ctx_t * slot_ctx ) {
 FD_SCRATCH_SCOPE_BEGIN {
   fd_epoch_bank_t * epoch_bank = fd_exec_epoch_ctx_epoch_bank( slot_ctx->epoch_ctx );
   fd_stakes_t * stakes = &epoch_bank->stakes;
+  stakes->total_stake = 0UL;
 
   // TODO: is this size correct if the same stake account is in both the slot and epoch cache? Is this possible?
   ulong stake_delegations_size = fd_delegation_pair_t_map_size(
@@ -4006,6 +4007,7 @@ FD_SCRATCH_SCOPE_BEGIN {
     } else {
       epoch_cache_node->elem.stake = n->elem.stake;
     }
+    stakes->total_stake = fd_ulong_sat_add( stakes->total_stake, epoch_cache_node->elem.stake );
   }
 
   fd_bincode_destroy_ctx_t destroy_slot = {.valloc = slot_ctx->valloc};

src/flamenco/runtime/program/fd_vote_program.c

@@ -1933,7 +1933,7 @@ do_process_vote_state_update( fd_vote_state_t *           vote_state,
 }
 
 // ??
-static ulong
+ulong
 query_pubkey_stake( fd_pubkey_t const * pubkey, fd_vote_accounts_t const * vote_accounts ) {
   fd_vote_accounts_pair_t_mapnode_t key         = { 0 };
   key.elem.key                                  = *pubkey;

src/flamenco/runtime/program/fd_vote_program.h

@@ -77,6 +77,12 @@ void
 fd_vote_store_account( fd_exec_slot_ctx_t *    slot_ctx,
                        fd_borrowed_account_t * vote_account );
 
+/* Queries the delegated stake amount for the given vote account pubkey,
+   given the vote accounts map. */
+ulong 
+query_pubkey_stake( fd_pubkey_t const * pubkey,
+                    fd_vote_accounts_t const * vote_accounts );
+
 FD_PROTOTYPES_END
 
 #endif /* HEADER_fd_src_flamenco_runtime_program_fd_vote_program_h */

src/flamenco/types/fd_types.json

@@ -329,7 +329,7 @@
       "fields": [
         { "name": "vote_accounts", "type": "vote_accounts" },
         { "name": "stake_delegations", "type": "map", "element": "delegation_pair", "key": "account" },
-        { "name": "unused", "type": "ulong" },
+        { "name": "total_stake", "type": "ulong" },
         { "name": "epoch", "type": "ulong" },
         { "name": "stake_history", "type": "stake_history" }
       ],

src/flamenco/vm/syscall/fd_vm_syscall.c

@@ -27,6 +27,7 @@ fd_vm_syscall_register_slot( fd_sbpf_syscalls_t *       syscalls,
   int enable_alt_bn128_syscall             = 0;
   int enable_alt_bn128_compression_syscall = 0;
   int enable_last_restart_slot_syscall     = 0;
+  int enable_get_epoch_stake_syscall       = 0;
 
   int disable_fees_sysvar                  = 0;
 
@@ -38,6 +39,7 @@ fd_vm_syscall_register_slot( fd_sbpf_syscalls_t *       syscalls,
     enable_alt_bn128_syscall             = FD_FEATURE_ACTIVE( slot_ctx, enable_alt_bn128_syscall );
     enable_alt_bn128_compression_syscall = FD_FEATURE_ACTIVE( slot_ctx, enable_alt_bn128_compression_syscall );
     enable_last_restart_slot_syscall     = FD_FEATURE_ACTIVE( slot_ctx, last_restart_slot_sysvar );
+    enable_get_epoch_stake_syscall       = FD_FEATURE_ACTIVE( slot_ctx, enable_get_epoch_stake_syscall );
 
     disable_fees_sysvar                  = !FD_FEATURE_ACTIVE( slot_ctx, disable_fees_sysvar );
 
@@ -139,6 +141,10 @@ fd_vm_syscall_register_slot( fd_sbpf_syscalls_t *       syscalls,
   if( enable_alt_bn128_compression_syscall )
     REGISTER( "sol_alt_bn128_compression",           fd_vm_syscall_sol_alt_bn128_compression );
 
+  if ( enable_get_epoch_stake_syscall ) {
+    REGISTER( "sol_get_epoch_stake",                 fd_vm_syscall_sol_get_epoch_stake );
+  }
+
 # undef REGISTER
 
   return FD_VM_SUCCESS;

src/flamenco/vm/syscall/fd_vm_syscall.h

@@ -781,6 +781,10 @@ FD_VM_SYSCALL_DECL( sol_curve_group_op );
 
 FD_VM_SYSCALL_DECL( sol_curve_multiscalar_mul );
 
+/* syscall sol_get_epoch_stake */
+
+FD_VM_SYSCALL_DECL( sol_get_epoch_stake );
+
 int
 fd_vm_derive_pda( fd_vm_t *           vm,
                   fd_pubkey_t const * program_id,

src/flamenco/vm/syscall/fd_vm_syscall_runtime.c

@@ -6,6 +6,7 @@
 #include "../../runtime/sysvar/fd_sysvar_rent.h"
 #include "../../runtime/sysvar/fd_sysvar_last_restart_slot.h"
 #include "../../runtime/context/fd_exec_txn_ctx.h"
+#include "../../runtime/program/fd_vote_program.h"
 #include "../../runtime/context/fd_exec_instr_ctx.h"
 
 int
@@ -464,3 +465,69 @@ fd_vm_syscall_sol_get_processed_sibling_instruction(
   *ret = 0UL;
   return FD_VM_SUCCESS;
 }
+
+/* fd_vm_syscall_sol_get_epoch_stake */
+int
+fd_vm_syscall_sol_get_epoch_stake(
+    void * _vm,
+    ulong var_vaddr,
+    FD_PARAM_UNUSED ulong   r2,
+    FD_PARAM_UNUSED ulong   r3,
+    FD_PARAM_UNUSED ulong   r4,
+    FD_PARAM_UNUSED ulong   r5,
+    ulong * ret
+) {
+  fd_vm_t * vm = (fd_vm_t *)_vm;
+
+  /* https://github.com/firedancer-io/agave/blob/a68325a4264f4907067bd2f48526944347c606d4/programs/bpf_loader/src/syscalls/mod.rs#L2047 */
+  if ( var_vaddr == 0UL ) {
+    /* Consume base compute cost
+       https://github.com/firedancer-io/agave/blob/a68325a4264f4907067bd2f48526944347c606d4/programs/bpf_loader/src/syscalls/mod.rs#L2056 */
+    FD_VM_CU_UPDATE( vm, FD_VM_SYSCALL_BASE_COST );
+
+    fd_exec_instr_ctx_t const * instr_ctx = vm->instr_ctx;
+    if( FD_UNLIKELY( !instr_ctx ) ) return FD_VM_ERR_SIGCALL;
+
+    /* 
+    Return the total stake in this epoch
+
+    https://github.com/firedancer-io/agave/blob/a68325a4264f4907067bd2f48526944347c606d4/programs/bpf_loader/src/syscalls/mod.rs#L2048 */
+    ulong epoch_total_stake = instr_ctx->epoch_ctx->epoch_bank.stakes.total_stake;
+
+    /* 
+    Get the epoch stakes used to calculate the leader schedule for the current epoch.
+    
+    https://github.com/firedancer-io/agave/blob/a68325a4264f4907067bd2f48526944347c606d4/runtime/src/bank.rs#L6269 */
+    /* FIXME: get total epoch stake */
+
+    *ret = epoch_total_stake;
+    return FD_VM_SUCCESS;
+  }
+
+  /* Charge compute units: syscall_base + floor(PUBKEY_BYTES/cpi_bytes_per_unit) + mem_op_base
+
+    https://github.com/firedancer-io/agave/blob/a68325a4264f4907067bd2f48526944347c606d4/programs/bpf_loader/src/syscalls/mod.rs#L2073 */
+  FD_VM_CU_UPDATE( vm, fd_ulong_sat_add( 
+                          fd_ulong_sat_add(
+                            FD_VM_SYSCALL_BASE_COST,
+                            FD_PUBKEY_FOOTPRINT / FD_VM_CPI_BYTES_PER_UNIT ),
+                          FD_VM_MEM_OP_BASE_COST ) );
+
+  fd_exec_instr_ctx_t const * instr_ctx = vm->instr_ctx;
+  if( FD_UNLIKELY( !instr_ctx ) ) return FD_VM_ERR_SIGCALL;
+
+  /* Look up the amount of stake this vote account has, and return this.
+
+     https://github.com/firedancer-io/agave/blob/a68325a4264f4907067bd2f48526944347c606d4/programs/bpf_loader/src/syscalls/mod.rs#L2097 */
+  fd_pubkey_t const * vote_pubkey = FD_VM_MEM_HADDR_LD( 
+        vm,
+        var_vaddr,
+        FD_VM_ALIGN_RUST_PUBKEY,
+        FD_PUBKEY_FOOTPRINT );
+
+  ulong vote_account_stake = query_pubkey_stake(
+    vote_pubkey, &instr_ctx->epoch_ctx->epoch_bank.stakes.vote_accounts );
+
+  *ret = vote_account_stake;
+  return FD_VM_SUCCESS;
+}