run_make_support/
wasm.rs

1//! Wasm-specific helpers for various tests
2
3use wasmparser::{Parser, Payload};
4
5use crate::{Rustc, target};
6
7/// Returns whether the current compilation target will emit a WebAssembly
8/// component.
9pub fn target_emits_components() -> bool {
10    let target = target();
11    if target.contains("wasi") {
12        return !target.contains("wasip1");
13    }
14    if target.contains("component") {
15        return true;
16    }
17    return false;
18}
19
20/// Helper methods for the `Rustc` type.
21impl Rustc {
22    /// Helper to emit a core module for this wasm target, skipping the
23    /// component output part of compilation.
24    pub fn emit_wasm_core_module(&mut self) -> &mut Self {
25        if target_emits_components() {
26            self.arg("-Clink-arg=--skip-wit-component");
27        }
28        self
29    }
30}
31
32/// Returns the size, in bytes, of the wasm module in `bytes`.
33///
34/// This excludes custom sections to avoid counting easily strippable sections
35/// such as debuginfo.
36pub fn wasm_binary_size(bytes: &[u8]) -> usize {
37    let mut size = 0;
38    for payload in Parser::new(0).parse_all(bytes) {
39        let payload = payload.unwrap();
40        match payload {
41            // Don't count the size of custom sections as they're easily
42            // stripped, and don't double-count modules since this'll recurse
43            // into module.
44            Payload::CustomSection { .. } | Payload::ModuleSection { .. } => continue,
45            _ => {}
46        }
47        if let Some((_, range)) = payload.as_section() {
48            size += range.len();
49        }
50    }
51    size
52}
run_make_support/wasm.rs

run_make_support/
wasm.rs
