From 782cb9437be91f9d9c912d52a8f9c0bc92f41eaf Mon Sep 17 00:00:00 2001
From: Brendan Chou <3680392+BrendanChou@users.noreply.github.com>
Date: Tue, 28 May 2024 11:05:37 -0400
Subject: [PATCH] remove use of BigIntMulSignedPpm in favor of BigMulPpm

---
 protocol/lib/big_math.go                       | 11 -----------
 protocol/x/clob/keeper/mev.go                  |  2 +-
 protocol/x/clob/keeper/process_single_match.go |  4 ++--
 protocol/x/clob/types/pending_updates.go       |  2 +-
 protocol/x/rewards/keeper/keeper.go            |  2 +-
 5 files changed, 5 insertions(+), 16 deletions(-)

diff --git a/protocol/lib/big_math.go b/protocol/lib/big_math.go
index 35ee84f6cf..d9befbcf1d 100644
--- a/protocol/lib/big_math.go
+++ b/protocol/lib/big_math.go
@@ -74,17 +74,6 @@ func BigIntMulPpm(input *big.Int, ppm uint32) *big.Int {
 	return result.Div(result, big.NewInt(int64(OneMillion)))
 }
 
-// BigIntMulSignedPpm takes a `big.Int` and returns the result of `input * ppm / 1_000_000`.
-func BigIntMulSignedPpm(input *big.Int, ppm int32, roundUp bool) *big.Int {
-	result := new(big.Rat)
-	result.Mul(
-		new(big.Rat).SetInt(input),
-		new(big.Rat).SetInt64(int64(ppm)),
-	)
-	result.Quo(result, BigRatOneMillion())
-	return BigRatRound(result, roundUp)
-}
-
 // BigMin takes two `big.Int` as parameters and returns the smaller one.
 func BigMin(a, b *big.Int) *big.Int {
 	result := new(big.Int)
diff --git a/protocol/x/clob/keeper/mev.go b/protocol/x/clob/keeper/mev.go
index d9987425c5..9f8a4e6b2c 100644
--- a/protocol/x/clob/keeper/mev.go
+++ b/protocol/x/clob/keeper/mev.go
@@ -874,7 +874,7 @@ func (c *CumulativePnL) AddPnLForTradeWithFilledQuoteQuantums(
 	}
 
 	// Calculate fees.
-	bigFeeQuoteQuantums := lib.BigIntMulSignedPpm(filledQuoteQuantums, feePpm, true)
+	bigFeeQuoteQuantums := lib.BigMulPpm(filledQuoteQuantums, feePpm, true)
 	pnl.Sub(pnl, bigFeeQuoteQuantums)
 
 	c.AddDeltaToSubaccount(subaccountId, pnl)
diff --git a/protocol/x/clob/keeper/process_single_match.go b/protocol/x/clob/keeper/process_single_match.go
index 7410bdd140..d3201234aa 100644
--- a/protocol/x/clob/keeper/process_single_match.go
+++ b/protocol/x/clob/keeper/process_single_match.go
@@ -317,8 +317,8 @@ func (k Keeper) persistMatchedOrders(
 	isTakerLiquidation := matchWithOrders.TakerOrder.IsLiquidation()
 
 	// Taker fees and maker fees/rebates are rounded towards positive infinity.
-	bigTakerFeeQuoteQuantums := lib.BigIntMulSignedPpm(bigFillQuoteQuantums, takerFeePpm, true)
-	bigMakerFeeQuoteQuantums := lib.BigIntMulSignedPpm(bigFillQuoteQuantums, makerFeePpm, true)
+	bigTakerFeeQuoteQuantums := lib.BigMulPpm(bigFillQuoteQuantums, takerFeePpm, true)
+	bigMakerFeeQuoteQuantums := lib.BigMulPpm(bigFillQuoteQuantums, makerFeePpm, true)
 
 	matchWithOrders.MakerFee = bigMakerFeeQuoteQuantums.Int64()
 	// Liquidation orders pay the liquidation fee instead of the standard taker fee
diff --git a/protocol/x/clob/types/pending_updates.go b/protocol/x/clob/types/pending_updates.go
index 1838df709c..d71015fc25 100644
--- a/protocol/x/clob/types/pending_updates.go
+++ b/protocol/x/clob/types/pending_updates.go
@@ -169,7 +169,7 @@ func (p *PendingUpdates) AddPerpetualFill(
 		totalFee = big.NewInt(0)
 	}
 
-	bigFeeQuoteQuantums := lib.BigIntMulSignedPpm(bigFillQuoteQuantums, feePpm, true)
+	bigFeeQuoteQuantums := lib.BigMulPpm(bigFillQuoteQuantums, feePpm, true)
 
 	totalFee.Add(
 		totalFee,
diff --git a/protocol/x/rewards/keeper/keeper.go b/protocol/x/rewards/keeper/keeper.go
index 8d414f81ea..69fb522556 100644
--- a/protocol/x/rewards/keeper/keeper.go
+++ b/protocol/x/rewards/keeper/keeper.go
@@ -136,7 +136,7 @@ func (k Keeper) AddRewardSharesForFill(
 	lowestMakerFee := k.feeTiersKeeper.GetLowestMakerFee(ctx)
 	maxMakerRebatePpm := lib.Min(int32(0), lowestMakerFee)
 	// Calculate quote_quantums * max_maker_rebate. Result is non-positive.
-	makerRebateMulTakerVolume := lib.BigIntMulSignedPpm(bigFillQuoteQuantums, maxMakerRebatePpm, false)
+	makerRebateMulTakerVolume := lib.BigMulPpm(bigFillQuoteQuantums, maxMakerRebatePpm, false)
 	takerWeight := new(big.Int).Add(
 		bigTakerFeeQuoteQuantums,
 		makerRebateMulTakerVolume,