use std::fmt::{Display, Formatter, Result, Write};
use flowgraph::ControlFlowGraph;
use ir::instructions::BranchInfo;
use ir::Function;
pub struct CFGPrinter<'a> {
func: &'a Function,
cfg: ControlFlowGraph,
}
impl<'a> CFGPrinter<'a> {
pub fn new(func: &'a Function) -> CFGPrinter<'a> {
CFGPrinter {
func,
cfg: ControlFlowGraph::with_function(func),
}
}
pub fn write(&self, w: &mut Write) -> Result {
self.header(w)?;
self.ebb_nodes(w)?;
self.cfg_connections(w)?;
writeln!(w, "}}")
}
fn header(&self, w: &mut Write) -> Result {
writeln!(w, "digraph \"{}\" {{", self.func.name)?;
if let Some(entry) = self.func.layout.entry_block() {
writeln!(w, " {{rank=min; {}}}", entry)?;
}
Ok(())
}
fn ebb_nodes(&self, w: &mut Write) -> Result {
for ebb in &self.func.layout {
write!(w, " {} [shape=record, label=\"{{{}", ebb, ebb)?;
for inst in self.func.layout.ebb_insts(ebb) {
let idata = &self.func.dfg[inst];
match idata.analyze_branch(&self.func.dfg.value_lists) {
BranchInfo::SingleDest(dest, _) => {
write!(w, " | <{}>{} {}", inst, idata.opcode(), dest)?
}
BranchInfo::Table(table) => {
write!(w, " | <{}>{} {}", inst, idata.opcode(), table)?
}
BranchInfo::NotABranch => {}
}
}
writeln!(w, "}}\"]")?
}
Ok(())
}
fn cfg_connections(&self, w: &mut Write) -> Result {
for ebb in &self.func.layout {
for (parent, inst) in self.cfg.pred_iter(ebb) {
writeln!(w, " {}:{} -> {}", parent, inst, ebb)?;
}
}
Ok(())
}
}
impl<'a> Display for CFGPrinter<'a> {
fn fmt(&self, f: &mut Formatter) -> Result {
self.write(f)
}
}