Fix mul_upper_s_s

assembly/math.ts

@@ -32,24 +32,29 @@ export function mulUpperUnsigned(a: u64, b: u64): u64 {
  * Same as [mulUpperUnsigned] but treat the arguments as signed (two-complement) 64-bit numbers and the result alike.
  */
 export function mulUpperSigned(a: i64, b: i64): u64 {
-  const aSign = a < 0 ? 1 : -1;
-  const bSign = b < 0 ? 1 : -1;
-  const sign = aSign * bSign;
+  let isResultNegative = false;
+  let aAbs = a;
+  let bAbs = b;
+  if (a < 0) {
+    isResultNegative = !isResultNegative;
+    aAbs = ~a + 1;
+  }
+  if (b < 0) {
+    isResultNegative = !isResultNegative;
+    bAbs = ~b + 1;
+  }
 
-  if (sign < 0) {
-    const aAbs: u64 = a < 0 ? ~a + 1 : a;
-    const bAbs: u64 = b < 0 ? ~b + 1 : b;
+  if (isResultNegative) {
     const upper = mulUpperUnsigned(aAbs, bAbs);
     const lower = aAbs * bAbs;
     return ~upper + (lower === 0 ? 1 : 0);
   }
 
-  return mulUpperUnsigned(a, b);
+  return mulUpperUnsigned(aAbs, bAbs);
 }
 
 export function mulUpperSignedUnsigned(a: i64, b: u64): u64 {
-  const aSign = a < 0 ? 1 : -1;
-  if (aSign === 1) {
+  if (a < 0) {
     const aAbs: u64 = ~a + 1;
     const upper = mulUpperUnsigned(aAbs, b);
     const lower = aAbs * b;

bin/fuzz.js

@@ -37,20 +37,24 @@ export function fuzz(data) {
       assert(pvm.getProgramCounter(), output.pc, 'pc');
     });
 
-    writeTestCase(
-      program,
-      {
-        pc,
-        gas,
-        registers,
-      },
-      {
-        status: pvm.getStatus(),
-        gasLeft: pvm.getGasLeft(),
-        pc: pvm.getProgramCounter(),
-        registers: pvm.getRegisters()
-      },
-    );
+    try {
+      writeTestCase(
+        program,
+        {
+          pc,
+          gas,
+          registers,
+        },
+        {
+          status: pvm.getStatus(),
+          gasLeft: pvm.getGasLeft(),
+          pc: pvm.getProgramCounter(),
+          registers: pvm.getRegisters()
+        },
+      );
+    } catch (e) {
+      console.warn('Unable to write file', e);
+    }
   } catch (e) {
     const hex = programHex(program);
     console.log(program);

package.json

@@ -15,7 +15,8 @@
 		"prestart": "npm run build",
 		"preweb": "npm run build",
 		"web": "npx live-server ./web",
-		"start": "node ./bin/index.js"
+		"start": "node ./bin/index.js",
+		"fuzz": "npx jazzer --sync ./bin/fuzz"
 	},
 	"keywords": [],
 	"author": "Fluffy Labs",