rust/src/librustc/middle/trans/basic_block.rs
Daniel Micay 6919cf5fe1 rename std::iterator to std::iter
The trait will keep the `Iterator` naming, but a more concise module
name makes using the free functions less verbose. The module will define
iterables in addition to iterators, as it deals with iteration in
general.
2013-09-09 03:21:46 -04:00

43 lines
1.3 KiB
Rust

// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use lib::llvm::{llvm, BasicBlockRef};
use middle::trans::value::{UserIterator, Value};
use std::iter::{Filter, Map};
pub struct BasicBlock(BasicBlockRef);
pub type PredIterator<'self> = Map<'self, Value, BasicBlock, Filter<'self, Value, UserIterator>>;
/**
* Wrapper for LLVM BasicBlockRef
*/
impl BasicBlock {
pub fn as_value(self) -> Value {
unsafe {
Value(llvm::LLVMBasicBlockAsValue(*self))
}
}
pub fn pred_iter(self) -> PredIterator {
self.as_value().user_iter()
.filter(|user| user.is_a_terminator_inst())
.map(|user| user.get_parent().unwrap())
}
pub fn get_single_predecessor(self) -> Option<BasicBlock> {
let mut iter = self.pred_iter();
match (iter.next(), iter.next()) {
(Some(first), None) => Some(first),
_ => None
}
}
}