enhance passes (#2229)

- remove hardcoded upper limit
- continue based on node count reduction
- emit verbose statistics

fixes #2226
This commit is contained in:
Alex Lam S.L
2017-07-13 02:18:59 +08:00
committed by GitHub
parent c615a1e80a
commit 458e3e15f0
3 changed files with 40 additions and 26 deletions
+1 -1
View File
@@ -721,7 +721,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
compressor from discarding function names. Useful for code relying on
`Function.prototype.name`. See also: the `keep_fnames` [mangle option](#mangle).
- `passes` -- default `1`. Number of times to run compress with a maximum of 3.
- `passes` -- default `1`. The maximum number of times to run compress.
In some cases more than one pass leads to further compressed code. Keep in
mind more passes will take more time.
+11 -1
View File
@@ -148,10 +148,20 @@ merge(Compressor.prototype, {
node.process_expression(true);
}
var passes = +this.options.passes || 1;
for (var pass = 0; pass < passes && pass < 3; ++pass) {
var last_count = 1 / 0;
for (var pass = 0; pass < passes; pass++) {
if (pass > 0 || this.option("reduce_vars"))
node.reset_opt_flags(this, true);
node = node.transform(this);
if (passes > 1) {
var count = 0;
node.walk(new TreeWalker(function() {
count++;
}));
this.info("pass " + pass + ": last_count: " + last_count + ", count: " + count);
if (count >= last_count) break;
last_count = count;
}
}
if (this.option("expression")) {
node.process_expression(false);
+28 -24
View File
@@ -71,11 +71,13 @@ non_hoisted_function_after_return_2a: {
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:51,16]",
"WARN: Dropping unused variable a [test/compress/issue-1034.js:48,20]",
"WARN: Dropping unused function nope [test/compress/issue-1034.js:55,21]",
"WARN: pass 0: last_count: Infinity, count: 37",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:53,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:53,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:56,12]",
"WARN: Dropping unused variable b [test/compress/issue-1034.js:51,20]",
"WARN: Dropping unused variable c [test/compress/issue-1034.js:53,16]",
"WARN: pass 1: last_count: 37, count: 18",
]
}
@@ -109,11 +111,11 @@ non_hoisted_function_after_return_2b: {
}
expect_warnings: [
// duplicate warnings no longer emitted
"WARN: Dropping unreachable code [test/compress/issue-1034.js:95,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:95,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:97,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:97,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:101,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:97,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:97,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:99,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:99,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:103,12]",
]
}
@@ -151,10 +153,10 @@ non_hoisted_function_after_return_strict: {
}
expect_stdout: "8 7"
expect_warnings: [
'WARN: Dropping unreachable code [test/compress/issue-1034.js:131,16]',
"WARN: Dropping unreachable code [test/compress/issue-1034.js:134,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:137,12]",
"WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:138,21]"
"WARN: Dropping unreachable code [test/compress/issue-1034.js:133,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:136,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:139,12]",
"WARN: Dropping unused function UnusedFunction [test/compress/issue-1034.js:140,21]",
]
}
@@ -194,17 +196,19 @@ non_hoisted_function_after_return_2a_strict: {
}
expect_stdout: "5 6"
expect_warnings: [
"WARN: Dropping unreachable code [test/compress/issue-1034.js:173,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:173,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:176,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:176,16]",
"WARN: Dropping unused variable a [test/compress/issue-1034.js:173,20]",
"WARN: Dropping unused function nope [test/compress/issue-1034.js:180,21]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:178,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:178,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:181,12]",
"WARN: Dropping unused variable b [test/compress/issue-1034.js:176,20]",
"WARN: Dropping unused variable c [test/compress/issue-1034.js:178,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:175,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:175,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:178,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:178,16]",
"WARN: Dropping unused variable a [test/compress/issue-1034.js:175,20]",
"WARN: Dropping unused function nope [test/compress/issue-1034.js:182,21]",
"WARN: pass 0: last_count: Infinity, count: 48",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:180,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:180,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:183,12]",
"WARN: Dropping unused variable b [test/compress/issue-1034.js:178,20]",
"WARN: Dropping unused variable c [test/compress/issue-1034.js:180,16]",
"WARN: pass 1: last_count: 48, count: 29",
]
}
@@ -243,10 +247,10 @@ non_hoisted_function_after_return_2b_strict: {
expect_stdout: "5 6"
expect_warnings: [
// duplicate warnings no longer emitted
"WARN: Dropping unreachable code [test/compress/issue-1034.js:225,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:225,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:227,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:227,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:229,16]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:229,16]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:231,12]",
"WARN: Declarations in unreachable code! [test/compress/issue-1034.js:231,12]",
"WARN: Dropping unreachable code [test/compress/issue-1034.js:235,12]",
]
}