Mauro Bringolf

WIP: Transpile sign extension proposal

14

Here is what I've been working on: * New package that transpiles sign extension instructions back to functions with the (hopefully) same behavior. * The functions replacing the instructions are...

Move local variables onto function node in AST

4

Currently we store them as instructions in the function body which is closer to text format, but conceptually not quite right since they're not instructions. I think we should move...

There are some restrictions on these arguments for the memory instructions to be well typed. * https://github.com/xtuc/webassemblyjs/blob/master/packages/validation/src/type-checker/get-type.js#L355 * https://github.com/xtuc/webassemblyjs/blob/master/packages/validation/src/type-checker/get-type.js#L373

The instructions related to tables are still missing from the type checker.

Nested instruction representation in AST

5

Our AST representation has different ways of representing nested instruction * `node.args`: https://github.com/xtuc/webassemblyjs/blob/master/packages/wast-parser/test/fixtures/return/expected.json#L18 * `node.instr`: https://github.com/xtuc/webassemblyjs/blob/master/packages/wast-parser/test/fixtures/instruction/nested-block/expected.json#L20 * `node.instrArgs`: https://github.com/xtuc/webassemblyjs/blob/d73d782786a02d97b21dd9285e20ada9911c219c/packages/wast-parser/test/fixtures/wast-call-instruction/expected.json#L11 This makes code working with them (in my case the type...

I noticed that the block node has `result: null` instead of `result: []` when its result type is omitted: https://github.com/xtuc/webassemblyjs/blob/master/packages/wast-parser/test/fixtures/block/empty/expected.json#L12 This should be `[]` for consistency, maybe there are other...

Another AST format change proposal. Conversion and memory instructions carry a type in their name (`store8`, `reinterpret/i32`, etc). We currently just store the instruction name and whatever package that requires...

Support NaN and Infinity text constants

2

The text format supports the following literals for floating point numbers * `nan`: https://github.com/WebAssembly/spec/blob/master/test/core/float_literals.wast#L5-L7 * `nan:0x...`: https://github.com/WebAssembly/spec/blob/master/test/core/float_literals.wast#L8-L13 * `inf`: https://github.com/WebAssembly/spec/blob/master/test/core/float_literals.wast#L14-L16 Spec is here https://webassembly.github.io/spec/core/text/values.html#text-float

Capture lost information of number values in JS floats

3

Since we are interpreting in JS it makes sense to use JS floats for all numbers and their operations wherever possible. However, I think there are a few problems with...

We need to ensure that only valid literals are used for each type by comparing the parsed value with the upper and lower bound of the ranges.