Files
wasmtime/cranelift/src/utils.rs
2019-10-24 09:54:31 -06:00

98 lines
3.0 KiB
Rust

//! Utility functions.
use cranelift_codegen::isa;
use cranelift_codegen::isa::TargetIsa;
use cranelift_codegen::settings::{self, FlagsOrIsa};
use cranelift_reader::{parse_options, Location};
use std::fs::File;
use std::io::{self, Read};
use std::path::Path;
use std::str::FromStr;
use target_lexicon::Triple;
/// Read an entire file into a string.
pub fn read_to_string<P: AsRef<Path>>(path: P) -> io::Result<String> {
let mut buffer = String::new();
if path.as_ref() == Path::new("-") {
let stdin = io::stdin();
let mut stdin = stdin.lock();
stdin.read_to_string(&mut buffer)?;
} else {
let mut file = File::open(path)?;
file.read_to_string(&mut buffer)?;
}
Ok(buffer)
}
/// Read an entire file into a vector of bytes.
#[cfg(feature = "wasm")]
pub fn read_to_end<P: AsRef<Path>>(path: P) -> io::Result<Vec<u8>> {
let mut buffer = Vec::new();
if path.as_ref() == Path::new("-") {
let stdin = io::stdin();
let mut stdin = stdin.lock();
stdin.read_to_end(&mut buffer)?;
} else {
let mut file = File::open(path)?;
file.read_to_end(&mut buffer)?;
}
Ok(buffer)
}
/// Like `FlagsOrIsa`, but holds ownership.
pub enum OwnedFlagsOrIsa {
Flags(settings::Flags),
Isa(Box<dyn TargetIsa>),
}
impl OwnedFlagsOrIsa {
/// Produce a FlagsOrIsa reference.
pub fn as_fisa(&self) -> FlagsOrIsa {
match *self {
Self::Flags(ref flags) => FlagsOrIsa::from(flags),
Self::Isa(ref isa) => FlagsOrIsa::from(&**isa),
}
}
}
/// Parse "set" and "triple" commands.
pub fn parse_sets_and_triple(
flag_set: &[String],
flag_triple: &str,
) -> Result<OwnedFlagsOrIsa, String> {
let mut flag_builder = settings::builder();
parse_options(
flag_set.iter().map(|x| x.as_str()),
&mut flag_builder,
Location { line_number: 0 },
)
.map_err(|err| err.to_string())?;
let mut words = flag_triple.trim().split_whitespace();
// Look for `target foo`.
if let Some(triple_name) = words.next() {
let triple = match Triple::from_str(triple_name) {
Ok(triple) => triple,
Err(parse_error) => return Err(parse_error.to_string()),
};
let mut isa_builder = isa::lookup(triple).map_err(|err| match err {
isa::LookupError::SupportDisabled => {
format!("support for triple '{}' is disabled", triple_name)
}
isa::LookupError::Unsupported => format!(
"support for triple '{}' is not implemented yet",
triple_name
),
})?;
// Apply the ISA-specific settings to `isa_builder`.
parse_options(words, &mut isa_builder, Location { line_number: 0 })
.map_err(|err| err.to_string())?;
Ok(OwnedFlagsOrIsa::Isa(
isa_builder.finish(settings::Flags::new(flag_builder)),
))
} else {
Ok(OwnedFlagsOrIsa::Flags(settings::Flags::new(flag_builder)))
}
}