diff --git a/benchmark/index.js b/benchmark/index.js
index f9f544c..9912e18 100644
--- a/benchmark/index.js
+++ b/benchmark/index.js
@@ -1,6 +1,6 @@
 import { run, mark, utils } from 'micro-bmark';
 import * as sm from 'sm-crypto'
-import * as smV2 from '../dist/index.js'
+import * as smV2 from 'sm-crypto-v2'
 
 const msg = 'Hello world~!'
 const longMsg = msg.repeat(10000)
diff --git a/src/sm2/globalThis.ts b/src/sm2/globalThis.ts
new file mode 100644
index 0000000..be5a199
--- /dev/null
+++ b/src/sm2/globalThis.ts
@@ -0,0 +1,21 @@
+
+(function (Object) {
+  typeof globalThis !== 'object' && (
+    // @ts-ignore
+    this ?
+      get() :
+      (Object.defineProperty(Object.prototype, '_T_', {
+        configurable: true,
+        get: get
+    // @ts-ignore
+      }), _T_)
+  );
+  function get() {
+    // @ts-ignore
+    var global = this || self;
+    global.globalThis = global;
+    // @ts-ignore
+    delete Object.prototype._T_;
+  }
+}(Object));
+export default globalThis as any;
\ No newline at end of file
diff --git a/src/sm2/index.ts b/src/sm2/index.ts
index 9a5f87a..3ae0453 100644
--- a/src/sm2/index.ts
+++ b/src/sm2/index.ts
@@ -19,14 +19,39 @@ export const EmptyArray = new Uint8Array()
 /**
  * 加密
  */
+class LRUMap<K, V> extends Map<K, V> {
+  length: number
+  constructor(length: number) {
+    super();
+    this.length = length;
+  }
+  set(key: K, value: V) {
+    super.delete(this.size < this.length ? key : super.keys().next().value);
+    return super.set(key, value);
+  }
+}
+// 保存最后 3 个加密的公钥，用来保证在这个情况下，性能不退化的太厉害
+const precomputedPublicKey = new LRUMap<string, ProjPointType<JSBI>>(3)
 export function doEncrypt(msg: string | Uint8Array, publicKey: string | ProjPointType<JSBI>, cipherMode = 1, options?: {
   asn1?: boolean // 使用 ASN.1 对 C1 编码
 }) {
-
   const msgArr = typeof msg === 'string' ? hexToArray(utf8ToHex(msg)) : Uint8Array.from(msg)
-  const publicKeyPoint = typeof publicKey === 'string' ? sm2Curve.ProjectivePoint.fromHex(publicKey) :
-    publicKey
-
+  let publicKeyPoint: ProjPointType<JSBI>
+  if (typeof publicKey === 'string') {
+    const cached = precomputedPublicKey.get(publicKey)
+    if (cached) {
+      publicKeyPoint = cached
+    } else {
+      const point = sm2Curve.ProjectivePoint.fromHex(publicKey)
+      sm2Curve.utils.precompute(undefined, point)
+      precomputedPublicKey.set(publicKey, point)
+      publicKeyPoint = point
+    }
+  } else {
+    publicKeyPoint = publicKey
+  }
+  // publicKeyPoint = typeof publicKey === 'string' ? sm2Curve.ProjectivePoint.fromHex(publicKey) :
+  //   publicKey
   const keypair = generateKeyPairHex()
   const k = utils.hexToNumber(keypair.privateKey)
 
@@ -222,7 +247,22 @@ export function doVerifySignature(msg: string | Uint8Array, signHex: string, pub
     s = utils.hexToNumber(signHex.substring(64))
   }
   
-  const PA = typeof publicKey === 'string' ? sm2Curve.ProjectivePoint.fromHex(publicKey) : publicKey
+  let PA: ProjPointType<JSBI>
+  
+  if (typeof publicKey === 'string') {
+    const cached = precomputedPublicKey.get(publicKey)
+    if (cached) {
+      PA = cached
+    } else {
+      const point = sm2Curve.ProjectivePoint.fromHex(publicKey)
+      sm2Curve.utils.precompute(undefined, point)
+      precomputedPublicKey.set(publicKey, point)
+      PA = point
+    }
+  } else {
+    PA = publicKey
+  }
+
   const e = utils.hexToNumber(hashHex)
   
   // t = (r + s) mod n
diff --git a/src/sm2/rng.ts b/src/sm2/rng.ts
index 6ccc06b..68d18cd 100644
--- a/src/sm2/rng.ts
+++ b/src/sm2/rng.ts
@@ -5,6 +5,8 @@
 // Web: globalThis.crypto
 // Node: async import("crypto").webcrypto
 // Mini Program: wx.getRandomValues
+import globalThis from './globalThis';
+
 declare module wx {
   function getRandomValues(options: {
     length: number;
diff --git a/src/sm2/sm3.ts b/src/sm2/sm3.ts
index 3154a4e..c5ff4c9 100644
--- a/src/sm2/sm3.ts
+++ b/src/sm2/sm3.ts
@@ -1,16 +1,17 @@
 // import assert from './_assert.js';
+import JSBI from 'jsbi';
 import { Hash, createView, Input, toBytes, wrapConstructor } from '../sm3/utils.js';
 
 const BoolA = (A: number, B: number, C: number) => ((A & B) | (A & C)) | (B & C)
 const BoolB = (A: number, B: number, C: number) => ((A ^ B) ^ C)
 const BoolC = (A: number, B: number, C: number) => (A & B) | ((~A) & C)
 // Polyfill for Safari 14
-function setBigUint64(view: DataView, byteOffset: number, value: bigint, isLE: boolean): void {
-  if (typeof view.setBigUint64 === 'function') return view.setBigUint64(byteOffset, value, isLE);
-  const _32n = BigInt(32);
-  const _u32_max = BigInt(0xffffffff);
-  const wh = Number((value >> _32n) & _u32_max);
-  const wl = Number(value & _u32_max);
+function setBigUint64(view: DataView, byteOffset: number, value: JSBI, isLE: boolean): void {
+  // if (typeof view.setBigUint64 === 'function') return view.setBigUint64(byteOffset, value, isLE);
+  const _32n = JSBI.BigInt(32);
+  const _u32_max = JSBI.BigInt(0xffffffff);
+  const wh = Number((JSBI.bitwiseAnd(JSBI.signedRightShift(value, _32n), _u32_max)));
+  const wl = Number(JSBI.bitwiseAnd(value, _u32_max));
   const h = isLE ? 4 : 0;
   const l = isLE ? 0 : 4;
   view.setUint32(byteOffset + h, wh, isLE);
@@ -120,7 +121,7 @@ export abstract class SHA2<T extends SHA2<T>> extends Hash<T> {
     // Note: sha512 requires length to be 128bit integer, but length in JS will overflow before that
     // You need to write around 2 exabytes (u64_max / 8 / (1024**6)) for this to happen.
     // So we just write lowest 64 bits of that value.
-    setBigUint64(view, blockLen - 8, BigInt(this.length * 8), isLE);
+    setBigUint64(view, blockLen - 8, JSBI.BigInt(this.length * 8), isLE);
     this.process(view, 0);
     const oview = createView(out);
     const len = this.outputLen;