Files
wasmtime/src/filetest/domtree.rs
Jakob Stoklund Olesen f84e218a93 Rename the 'cfg' module to 'flowgraph'.
The 'cfg' name was easy to confuse with 'configuration'.
2017-03-21 15:33:23 -07:00

107 lines
4.0 KiB
Rust

//! Test command for verifying dominator trees.
//!
//! The `test domtree` test command looks for annotations on instructions like this:
//!
//! jump ebb3 ; dominates: ebb3
//!
//! This annotation means that the jump instruction is expected to be the immediate dominator of
//! `ebb3`.
//!
//! We verify that the dominator tree annotations are complete and correct.
//!
use cretonne::dominator_tree::DominatorTree;
use cretonne::flowgraph::ControlFlowGraph;
use cretonne::ir::Function;
use cretonne::ir::entities::AnyEntity;
use cton_reader::TestCommand;
use filetest::subtest::{SubTest, Context, Result};
use std::borrow::{Borrow, Cow};
use std::collections::HashMap;
use utils::match_directive;
struct TestDomtree;
pub fn subtest(parsed: &TestCommand) -> Result<Box<SubTest>> {
assert_eq!(parsed.command, "domtree");
if !parsed.options.is_empty() {
Err(format!("No options allowed on {}", parsed))
} else {
Ok(Box::new(TestDomtree))
}
}
impl SubTest for TestDomtree {
fn name(&self) -> Cow<str> {
Cow::from("domtree")
}
// Extract our own dominator tree from
fn run(&self, func: Cow<Function>, context: &Context) -> Result<()> {
let func = func.borrow();
let cfg = ControlFlowGraph::with_function(func);
let domtree = DominatorTree::with_function(func, &cfg);
// Build an expected domtree from the source annotations.
let mut expected = HashMap::new();
for comment in &context.details.comments {
if let Some(tail) = match_directive(comment.text, "dominates:") {
let inst = match comment.entity {
AnyEntity::Inst(inst) => inst,
_ => {
return Err(format!("annotation on non-inst {}: {}",
comment.entity,
comment.text))
}
};
for src_ebb in tail.split_whitespace() {
let ebb = match context.details.map.lookup_str(src_ebb) {
Some(AnyEntity::Ebb(ebb)) => ebb,
_ => return Err(format!("expected EBB: {}", src_ebb)),
};
// Annotations say that `inst` is the idom of `ebb`.
if expected.insert(ebb, inst).is_some() {
return Err(format!("multiple dominators for {}", src_ebb));
}
// Compare to computed domtree.
match domtree.idom(ebb) {
Some(got_inst) if got_inst != inst => {
return Err(format!("mismatching idoms for {}:\n\
want: {}, got: {}",
src_ebb,
inst,
got_inst));
}
None => {
return Err(format!("mismatching idoms for {}:\n\
want: {}, got: unreachable",
src_ebb,
inst));
}
_ => {}
}
}
}
}
// Now we know that everything in `expected` is consistent with `domtree`.
// All other EBB's should be either unreachable or the entry block.
for ebb in func.layout
.ebbs()
.skip(1)
.filter(|ebb| !expected.contains_key(&ebb)) {
if let Some(got_inst) = domtree.idom(ebb) {
return Err(format!("mismatching idoms for renumbered {}:\n\
want: unrechable, got: {}",
ebb,
got_inst));
}
}
Ok(())
}
}