fix(es/minifier): Don't drop used variables from sequential inliner (#…

…6520) **Related issue:** - Closes #6510.
swc-project · Nov 29, 2022 · b394f9f · b394f9f · github-actions · Nov 29, 2022
1 parent 08e1c50
commit b394f9f
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Showing 8 changed files with 125 additions and 2 deletions.
diff --git a/crates/swc/tests/tsc-references/nonPrimitiveAssignError.2.minified.js b/crates/swc/tests/tsc-references/nonPrimitiveAssignError.2.minified.js
@@ -4,4 +4,4 @@ var a, x = {}, y = {
 };
 x = a, y = a, a = x, a = y;
 var s = "fooo";
-a = 123, a = !0, n = a = s, b = a, s = a, a = 123, a = !0, a = "string";
+a = 123, a = !0, s = a = s, a = 123, a = !0, a = "string";
diff --git a/crates/swc_ecma_minifier/src/compress/optimize/sequences.rs b/crates/swc_ecma_minifier/src/compress/optimize/sequences.rs
@@ -2222,7 +2222,8 @@ where
                             if let Some(usage) = self.data.vars.get(&left_id.to_id()) {
                                 // We are eliminating one usage, so we use 1 instead of
                                 // 0
-                                if !$force_drop && usage.usage_count == 1 {
+                                if !$force_drop && usage.usage_count == 1 && usage.assign_count == 0
+                                {
                                     report_change!("sequences: Dropping inlined variable");
                                     a.name.take();
                                 }

diff --git a/crates/swc_ecma_minifier/tests/fixture/next/joda/input.js b/crates/swc_ecma_minifier/tests/fixture/next/joda/input.js
@@ -0,0 +1,26 @@
+"use strict";
+(self["webpackChunk_N_E"] = self["webpackChunk_N_E"] || []).push([[715], {
+
+/***/ 3266:
+/***/ (function (__unused_webpack_module, __webpack_exports__, __webpack_require__) {
+
+/* harmony export */ __webpack_require__.d(__webpack_exports__, {
+/* harmony export */   "h": function () { return /* binding */ LocalDate; }
+  /* harmony export */
+});
+
+      var isInit = false;
+
+      function init() {
+        if (isInit) {
+          return;
+        }
+
+        isInit = true;
+      }
+
+      init();
+
+    })
+
+}]);
diff --git a/crates/swc_ecma_minifier/tests/fixture/next/joda/output.js b/crates/swc_ecma_minifier/tests/fixture/next/joda/output.js
@@ -0,0 +1,15 @@
+"use strict";
+(self.webpackChunk_N_E = self.webpackChunk_N_E || []).push([
+    [
+        715
+    ],
+    {
+        3266: function(__unused_webpack_module, __webpack_exports__, __webpack_require__) {
+            __webpack_require__.d(__webpack_exports__, {
+                h: function() {
+                    return LocalDate;
+                }
+            });
+        }
+    }
+]);
diff --git a/crates/swc_ecma_minifier/tests/pass-1/joda/1/input.js b/crates/swc_ecma_minifier/tests/pass-1/joda/1/input.js
@@ -0,0 +1,26 @@
+"use strict";
+(self["webpackChunk_N_E"] = self["webpackChunk_N_E"] || []).push([[715], {
+
+/***/ 3266:
+/***/ (function (__unused_webpack_module, __webpack_exports__, __webpack_require__) {
+
+/* harmony export */ __webpack_require__.d(__webpack_exports__, {
+/* harmony export */   "h": function () { return /* binding */ LocalDate; }
+  /* harmony export */
+});
+
+      var isInit = false;
+
+      function init() {
+        if (isInit) {
+          return;
+        }
+
+        isInit = true;
+      }
+
+      init();
+
+    })
+
+}]);
diff --git a/crates/swc_ecma_minifier/tests/pass-1/joda/1/output.js b/crates/swc_ecma_minifier/tests/pass-1/joda/1/output.js
@@ -0,0 +1,19 @@
+"use strict";
+(self.webpackChunk_N_E = self.webpackChunk_N_E || []).push([
+    [
+        715
+    ],
+    {
+        3266: function(__unused_webpack_module, __webpack_exports__, __webpack_require__) {
+            __webpack_require__.d(__webpack_exports__, {
+                h: function() {
+                    return LocalDate;
+                }
+            });
+            var isInit = !1;
+            !function() {
+                if (!isInit) isInit = !0;
+            }();
+        }
+    }
+]);
diff --git a/crates/swc_ecma_minifier/tests/pass-1/joda/2/input.js b/crates/swc_ecma_minifier/tests/pass-1/joda/2/input.js
@@ -0,0 +1,19 @@
+"use strict";
+(self.webpackChunk_N_E = self.webpackChunk_N_E || []).push([
+  [
+    715
+  ],
+  {
+    3266: function (__unused_webpack_module, __webpack_exports__, __webpack_require__) {
+      __webpack_require__.d(__webpack_exports__, {
+        h: function () {
+          return LocalDate;
+        }
+      });
+      var isInit = !1;
+      !function () {
+        if (!isInit) isInit = !0;
+      }();
+    }
+  }
+]);
diff --git a/crates/swc_ecma_minifier/tests/pass-1/joda/2/output.js b/crates/swc_ecma_minifier/tests/pass-1/joda/2/output.js
@@ -0,0 +1,17 @@
+"use strict";
+(self.webpackChunk_N_E = self.webpackChunk_N_E || []).push([
+    [
+        715
+    ],
+    {
+        3266: function(__unused_webpack_module, __webpack_exports__, __webpack_require__) {
+            __webpack_require__.d(__webpack_exports__, {
+                h: function() {
+                    return LocalDate;
+                }
+            });
+            var isInit = !1;
+            isInit = !0;
+        }
+    }
+]);
Benchmark suite	Current: `b394f9f`	Previous: `e3cbe7e`	Ratio
`es/full/bugs-1`	`350508` ns/iter (`± 29305`)	`376952` ns/iter (`± 63545`)	`0.93`
`es/full/minify/libraries/antd`	`2111879218` ns/iter (`± 98075579`)	`2206985732` ns/iter (`± 42259483`)	`0.96`
`es/full/minify/libraries/d3`	`477253912` ns/iter (`± 23150529`)	`484973260` ns/iter (`± 39467533`)	`0.98`
`es/full/minify/libraries/echarts`	`1768784942` ns/iter (`± 44996832`)	`1857187478` ns/iter (`± 510194701`)	`0.95`
`es/full/minify/libraries/jquery`	`120848711` ns/iter (`± 1356858`)	`130091506` ns/iter (`± 20044770`)	`0.93`
`es/full/minify/libraries/lodash`	`139617902` ns/iter (`± 9597166`)	`146377125` ns/iter (`± 26383586`)	`0.95`
`es/full/minify/libraries/moment`	`69739935` ns/iter (`± 3553422`)	`71872937` ns/iter (`± 1502540`)	`0.97`
`es/full/minify/libraries/react`	`22974476` ns/iter (`± 143473`)	`23211015` ns/iter (`± 684772`)	`0.99`
`es/full/minify/libraries/terser`	`397168315` ns/iter (`± 43026278`)	`383136017` ns/iter (`± 18860054`)	`1.04`
`es/full/minify/libraries/three`	`659201334` ns/iter (`± 35529274`)	`711727581` ns/iter (`± 62140383`)	`0.93`
`es/full/minify/libraries/typescript`	`3985253857` ns/iter (`± 60110808`)	`4053621880` ns/iter (`± 71180315`)	`0.98`
`es/full/minify/libraries/victory`	`956683828` ns/iter (`± 30089334`)	`999038812` ns/iter (`± 62498851`)	`0.96`
`es/full/minify/libraries/vue`	`185152232` ns/iter (`± 4541908`)	`192076773` ns/iter (`± 10135522`)	`0.96`
`es/full/codegen/es3`	`33985` ns/iter (`± 1272`)	`34210` ns/iter (`± 5190`)	`0.99`
`es/full/codegen/es5`	`34084` ns/iter (`± 656`)	`33777` ns/iter (`± 4969`)	`1.01`
`es/full/codegen/es2015`	`34032` ns/iter (`± 631`)	`33849` ns/iter (`± 4475`)	`1.01`
`es/full/codegen/es2016`	`33974` ns/iter (`± 802`)	`34213` ns/iter (`± 5357`)	`0.99`
`es/full/codegen/es2017`	`34080` ns/iter (`± 1291`)	`33764` ns/iter (`± 4339`)	`1.01`
`es/full/codegen/es2018`	`34071` ns/iter (`± 648`)	`33728` ns/iter (`± 3952`)	`1.01`
`es/full/codegen/es2019`	`34126` ns/iter (`± 374`)	`33797` ns/iter (`± 1742`)	`1.01`
`es/full/codegen/es2020`	`34227` ns/iter (`± 1533`)	`34018` ns/iter (`± 1077`)	`1.01`
`es/full/all/es3`	`205468621` ns/iter (`± 11777873`)	`213102648` ns/iter (`± 20481603`)	`0.96`
`es/full/all/es5`	`187566358` ns/iter (`± 14030526`)	`195372280` ns/iter (`± 18757534`)	`0.96`
`es/full/all/es2015`	`148442741` ns/iter (`± 11936301`)	`155940559` ns/iter (`± 14707035`)	`0.95`
`es/full/all/es2016`	`146573299` ns/iter (`± 9311702`)	`150608362` ns/iter (`± 16151921`)	`0.97`
`es/full/all/es2017`	`145423013` ns/iter (`± 8809769`)	`149342192` ns/iter (`± 12163642`)	`0.97`
`es/full/all/es2018`	`145189265` ns/iter (`± 8078586`)	`148412554` ns/iter (`± 17358285`)	`0.98`
`es/full/all/es2019`	`144159830` ns/iter (`± 8356838`)	`147093097` ns/iter (`± 16962553`)	`0.98`
`es/full/all/es2020`	`138094151` ns/iter (`± 7190825`)	`141669916` ns/iter (`± 9577567`)	`0.97`
`es/full/parser`	`730601` ns/iter (`± 47270`)	`735105` ns/iter (`± 43330`)	`0.99`
`es/full/base/fixer`	`26442` ns/iter (`± 734`)	`26692` ns/iter (`± 2253`)	`0.99`
`es/full/base/resolver_and_hygiene`	`91909` ns/iter (`± 3392`)	`93471` ns/iter (`± 12030`)	`0.98`
`serialization of ast node`	`217` ns/iter (`± 7`)	`217` ns/iter (`± 11`)	`1`
`serialization of serde`	`221` ns/iter (`± 2`)	`223` ns/iter (`± 32`)	`0.99`