diff --git a/benchmark/es/defaultparams-bench.js b/benchmark/es/defaultparams-bench.js
index 1393abbe54395c..ce2132718ca369 100644
--- a/benchmark/es/defaultparams-bench.js
+++ b/benchmark/es/defaultparams-bench.js
@@ -38,10 +38,10 @@ function runDefaultParams(n) {
   bench.end(n / 1e6);
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
+function main({ millions, method }) {
+  const n = millions * 1e6;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'withoutdefaults':
diff --git a/benchmark/es/destructuring-bench.js b/benchmark/es/destructuring-bench.js
index a6c9a81ae02895..f244506860d248 100644
--- a/benchmark/es/destructuring-bench.js
+++ b/benchmark/es/destructuring-bench.js
@@ -34,10 +34,10 @@ function runSwapDestructured(n) {
   bench.end(n / 1e6);
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
+function main({ millions, method }) {
+  const n = millions * 1e6;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'swap':
diff --git a/benchmark/es/destructuring-object-bench.js b/benchmark/es/destructuring-object-bench.js
index 63e085a2424430..73687f018de9dd 100644
--- a/benchmark/es/destructuring-object-bench.js
+++ b/benchmark/es/destructuring-object-bench.js
@@ -33,10 +33,10 @@ function runDestructured(n) {
   bench.end(n / 1e6);
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
+function main({ millions, method }) {
+  const n = millions * 1e6;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'normal':
diff --git a/benchmark/es/foreach-bench.js b/benchmark/es/foreach-bench.js
index 62aa02236fc7ae..c7caa7cee6f461 100644
--- a/benchmark/es/foreach-bench.js
+++ b/benchmark/es/foreach-bench.js
@@ -52,17 +52,15 @@ function useForEach(n, items) {
   bench.end(n / 1e6);
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
-  const count = +conf.count;
-
+function main({ millions, count, method }) {
+  const n = millions * 1e6;
   const items = new Array(count);
   var i;
   var fn;
   for (i = 0; i < count; i++)
     items[i] = i;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'for':
diff --git a/benchmark/es/map-bench.js b/benchmark/es/map-bench.js
index 035ed1a22aaf91..ba8e35c2eb934f 100644
--- a/benchmark/es/map-bench.js
+++ b/benchmark/es/map-bench.js
@@ -108,10 +108,10 @@ function runMap(n) {
   bench.end(n / 1e6);
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
+function main({ millions, method }) {
+  const n = millions * 1e6;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'object':
diff --git a/benchmark/es/restparams-bench.js b/benchmark/es/restparams-bench.js
index 32fa985dedb806..78299d292ce6f6 100644
--- a/benchmark/es/restparams-bench.js
+++ b/benchmark/es/restparams-bench.js
@@ -60,10 +60,10 @@ function runUseArguments(n) {
   bench.end(n / 1e6);
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
+function main({ millions, method }) {
+  const n = millions * 1e6;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'copy':
diff --git a/benchmark/es/spread-bench.js b/benchmark/es/spread-bench.js
index b6dfb5963e7acc..3c6cc93ea4f817 100644
--- a/benchmark/es/spread-bench.js
+++ b/benchmark/es/spread-bench.js
@@ -23,16 +23,16 @@ function makeTest(count, rest) {
   }
 }
 
-function main(conf) {
-  const n = +conf.millions * 1e6;
-  const ctx = conf.context === 'context' ? {} : null;
-  var fn = makeTest(conf.count, conf.rest);
-  const args = new Array(conf.count);
+function main({ millions, context, count, rest, method }) {
+  const n = millions * 1e6;
+  const ctx = context === 'context' ? {} : null;
+  var fn = makeTest(count, rest);
+  const args = new Array(count);
   var i;
-  for (i = 0; i < conf.count; i++)
+  for (i = 0; i < count; i++)
     args[i] = i;
 
-  switch (conf.method) {
+  switch (method) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'apply':
diff --git a/benchmark/es/string-concatenations.js b/benchmark/es/string-concatenations.js
index b7f5c319361c6c..a40b7fa8c3b9f9 100644
--- a/benchmark/es/string-concatenations.js
+++ b/benchmark/es/string-concatenations.js
@@ -17,15 +17,13 @@ const configs = {
 const bench = common.createBenchmark(main, configs);
 
 
-function main(conf) {
-  const n = +conf.n;
-
+function main({ n, mode }) {
   const str = 'abc';
   const num = 123;
 
   let string;
 
-  switch (conf.mode) {
+  switch (mode) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'multi-concat':
diff --git a/benchmark/es/string-repeat.js b/benchmark/es/string-repeat.js
index 1ddc7db78c7f86..e5bdbb5cc193c1 100644
--- a/benchmark/es/string-repeat.js
+++ b/benchmark/es/string-repeat.js
@@ -12,14 +12,12 @@ const configs = {
 
 const bench = common.createBenchmark(main, configs);
 
-function main(conf) {
-  const n = +conf.n;
-  const size = +conf.size;
-  const character = conf.encoding === 'ascii' ? 'a' : '\ud83d\udc0e'; // '🐎'
+function main({ n, size, encoding, mode }) {
+  const character = encoding === 'ascii' ? 'a' : '\ud83d\udc0e'; // '🐎'
 
   let str;
 
-  switch (conf.mode) {
+  switch (mode) {
     case '':
       // Empty string falls through to next line as default, mostly for tests.
     case 'Array':