perf: Speedup coins.AmountOf() by removing many regex calls (backport #…

…10021) (#10166)

* perf: Speedup coins.AmountOf() by removing many regex calls (#10021)

(cherry picked from commit ed35bfd)

# Conflicts:
#	CHANGELOG.md

* fix conflict

* fix changelog

Co-authored-by: Dev Ojha <ValarDragon@users.noreply.github.com>
Co-authored-by: Robert Zaremba <robert@zaremba.ch>

CHANGELOG.md

@@ -37,6 +37,9 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## [Unreleased]
 
+### Improvements
+* (types) [\#10021](https://github.com/cosmos/cosmos-sdk/pull/10021) Speedup coins.AmountOf(), by removing many intermittent regex calls.
+
 ### Bug Fixes
 
 * (x/genutil) [#10104](https://github.com/cosmos/cosmos-sdk/pull/10104) Ensure the `init` command reads the `--home` flag value correctly.

types/coin.go

@@ -517,7 +517,12 @@ func (coins Coins) Empty() bool {
 // AmountOf returns the amount of a denom from coins
 func (coins Coins) AmountOf(denom string) Int {
 	mustValidateDenom(denom)
+	return coins.AmountOfNoDenomValidation(denom)
+}
 
+// AmountOfNoDenomValidation returns the amount of a denom from coins
+// without validating the denomination.
+func (coins Coins) AmountOfNoDenomValidation(denom string) Int {
 	switch len(coins) {
 	case 0:
 		return ZeroInt()
@@ -530,15 +535,16 @@ func (coins Coins) AmountOf(denom string) Int {
 		return ZeroInt()
 
 	default:
+		// Binary search the amount of coins remaining
 		midIdx := len(coins) / 2 // 2:1, 3:1, 4:2
 		coin := coins[midIdx]
 		switch {
 		case denom < coin.Denom:
-			return coins[:midIdx].AmountOf(denom)
+			return coins[:midIdx].AmountOfNoDenomValidation(denom)
 		case denom == coin.Denom:
 			return coin.Amount
 		default:
-			return coins[midIdx+1:].AmountOf(denom)
+			return coins[midIdx+1:].AmountOfNoDenomValidation(denom)
 		}
 	}
 }