Apply correct optimization and add documentation

aptos-move/framework/move-stdlib/sources/fixed_point32.move

@@ -56,6 +56,16 @@ module std::fixed_point32 {
         (val * multiplier.value) >> 32
     }
 
+    public fun multiply_u64_return_fixpoint32(val: u64, multiplier: FixedPoint32): FixedPoint32 {
+        // The product of two 64 bit values has 128 bits, so perform the
+        // multiplication with u128 types and keep the full 128 bit product
+        // to avoid losing accuracy.
+        let unscaled_product = (val as u128) * (multiplier.value as u128);
+        // Check whether the value is too large.
+        assert!(unscaled_product <= MAX_U64, EMULTIPLICATION);
+        create_from_raw_value((product as u64));
+    }
+
     /// Divide a u64 integer by a fixed-point number, truncating any
     /// fractional part of the quotient. This will abort if the divisor
     /// is zero or if the quotient overflows.

aptos-move/framework/supra-framework/sources/pbo_delegation_pool.move

@@ -1772,34 +1772,22 @@ module supra_framework::pbo_delegation_pool {
         let last_unlocked_period = unlock_schedule.last_unlock_period;
         let schedule_length = vector::length(&unlock_schedule.schedule);
         let cfraction = unlock_schedule.cumulative_unlocked_fraction;
-        while (last_unlocked_period < unlock_periods_passed
-            && fixed_point64::less(cfraction, one)) {
-            let next_fraction =
-                if (schedule_length <= last_unlocked_period) {
-                    *vector::borrow(&unlock_schedule.schedule, schedule_length - 1)
-                } else {
-                    *vector::borrow(&unlock_schedule.schedule, last_unlocked_period)
-                };
-            let next_fraction_unchanged = next_fraction == *vector::borrow(&unlock_schedule.schedule, schedule_length - 1);
-            // If next fraction is same as last unlocked period, then no need to fetch from schedule
-            if (next_fraction_unchanged) {
-                while (last_unlocked_period < unlock_periods_passed
-                    && fixed_point64::less(cfraction, one)) {
-                    cfraction = fixed_point64::add(cfraction, next_fraction);
-                    last_unlocked_period = last_unlocked_period + 1;
-                };
-            } else {
-                cfraction = fixed_point64::add(cfraction, next_fraction);
-
-                last_unlocked_period = last_unlocked_period + 1;
-            };
+        while (last_unlocked_period < unlock_periods_passed && fixed_point64::less(cfraction, one)
+                && last_unlocked_period < schedule_length) {
+            let next_fraction = *vector::borrow(&unlock_schedule.schedule, last_unlocked_period);
+            cfraction = fixed_point64::add(cfraction, next_fraction);
+            last_unlocked_period = last_unlocked_period + 1;
         };
 
+        let final_fraction= *vector::borrow(&unlock_schedule.schedule, schedule_length - 1);
+        // Fast foward calculation to current period and don't update last_unlocked_period since it is not used anymore
+        cfraction = fixed_point64::add(cfraction, fixed_point64::multiply_u128_return_fixpoint64((unlock_periods_passed - last_unlocked_period as u128), final_fraction));
+        cfraction = fixed_point64::min(cfraction, one);
+
         unlock_schedule.cumulative_unlocked_fraction = cfraction;
         unlock_schedule.last_unlock_period = unlock_periods_passed;
         let unlockable_amount = cached_unlockable_balance(delegator_addr, pool_address);
         amount <= unlockable_amount
-
     }
 
     /// Unlock `amount` from the active + pending_active stake of `delegator` or

aptos-move/framework/supra-framework/sources/vesting_without_staking.move

@@ -495,42 +495,35 @@ module supra_framework::vesting_without_staking {
             / vesting_schedule.period_duration;
 
         // Index is 0-based while period is 1-based so we need to subtract 1.
-        while (last_completed_period >= next_period_to_vest && vesting_record.left_amount > 0) {
-            let schedule_index = next_period_to_vest - 1;
-            let vesting_fraction = if (schedule_index < vector::length(schedule)) {
-                *vector::borrow(schedule, schedule_index)
-            } else {
-                // Last vesting schedule fraction will repeat until the grant runs out.
-                *vector::borrow(schedule, vector::length(schedule) - 1)
-            };
-            let vesting_fraction_unchange = vesting_fraction == *vector::borrow(schedule, vector::length(schedule) - 1);
-            if (vesting_fraction_unchange) {
-                while (last_completed_period >= next_period_to_vest && vesting_record.left_amount > 0) {
-                    vest_transfer(vesting_record, signer_cap, beneficiary, vesting_fraction);
-                    emit_event(&mut vesting_contract.vest_events,
-                        VestEvent {
-                            admin: vesting_contract.admin,
-                            shareholder_address: shareholder_address,
-                            vesting_contract_address: contract_address,
-                            period_vested: next_period_to_vest,
-                        },
-                    );
-                    next_period_to_vest = next_period_to_vest + 1;
-                }
-            } else {
-                vest_transfer(vesting_record, signer_cap, beneficiary, vesting_fraction);
-                emit_event(&mut vesting_contract.vest_events,
-                    VestEvent {
-                        admin: vesting_contract.admin,
-                        shareholder_address: shareholder_address,
-                        vesting_contract_address: contract_address,
-                        period_vested: next_period_to_vest,
-                    },
-                );
-                next_period_to_vest = next_period_to_vest + 1;
-            };
+        while (last_completed_period >= next_period_to_vest && vesting_record.left_amount > 0 && next_period_to_vest <= vector::length(schedule)) {
+            // let schedule_index = next_period_to_vest - 1;
+            let vesting_fraction = *vector::borrow(schedule, vector::length(schedule) - 1);
+            vest_transfer(vesting_record, signer_cap, beneficiary, vesting_fraction);
+            emit_event(&mut vesting_contract.vest_events,
+                VestEvent {
+                    admin: vesting_contract.admin,
+                    shareholder_address: shareholder_address,
+                    vesting_contract_address: contract_address,
+                    period_vested: next_period_to_vest,
+                },
+            );
+            next_period_to_vest = next_period_to_vest + 1;
         };
 
+        let final_fraction = *vector::borrow(schedule, vector::length(schedule) - 1);
+        let total_fraction = fixed_point32::multiply_u64_return_fixpoint32((last_completed_period - next_period_to_vest ), final_fraction);
+        // We don't need to check vesting_record.left_amount > 0 because vest_transfer will handle that.
+        vest_transfer(vesting_record, signer_cap, beneficiary, total_fraction);
+        next_period_to_vest = last_completed_period + 1;
+        emit_event(&mut vesting_contract.vest_events,
+            VestEvent {
+                admin: vesting_contract.admin,
+                shareholder_address: shareholder_address,
+                vesting_contract_address: contract_address,
+                period_vested: next_period_to_vest,
+            },
+        );
+
         //update last_vested_period for the shareholder
         vesting_record.last_vested_period = next_period_to_vest - 1;
     }