From b3fea30f84fef3ff7aa77775e00b83ba62d997cc Mon Sep 17 00:00:00 2001 From: Thomas Lively Date: Fri, 22 Mar 2024 16:56:33 -0700 Subject: [Strings] Represent string values as WTF-16 internally (#6418) WTF-16, i.e. arbitrary sequences of 16-bit values, is the encoding of Java and JavaScript strings, and using the same encoding makes the interpretation of string operations trivial, even when accounting for non-ascii characters. Specifically, use little-endian WTF-16. Re-encode string constants from WTF-8 to WTF-16 in the parsers, then back to WTF-8 in the writers. Update the constructor for string `Literal`s to interpret the string as WTF-16 and store a sequence of WTF-16 code units, i.e. 16-bit integers. Update `Builder::makeConstantExpression` accordingly to convert from the new `Literal` string representation back to a WTF-16 string. Update the interpreter to remove the logic for detecting non-ascii characters and bailing out. The naive implementations of all the string operations are correct now that our string encoding matches the JS string encoding. --- CHANGELOG.md | 1 + 1 file changed, 1 insertion(+) (limited to 'CHANGELOG.md') diff --git a/CHANGELOG.md b/CHANGELOG.md index ba9adda87..c4b81c710 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -21,6 +21,7 @@ Current Trunk - Add a new `BinaryenModuleReadWithFeatures` function to the C API that allows to configure which features to enable in the parser. - The build-time option to use legacy WasmGC opcodes is removed. + - The strings in `string.const` instructions must now be valid WTF-8. v117 ---- -- cgit v1.2.3