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use ir::Function;
use isa::TargetIsa;
use regalloc::RegDiversions;
use timing;
pub fn shrink_instructions(func: &mut Function, isa: &TargetIsa) {
let _tt = timing::shrink_instructions();
let encinfo = isa.encoding_info();
let mut divert = RegDiversions::new();
for ebb in func.layout.ebbs() {
divert.clear();
for inst in func.layout.ebb_insts(ebb) {
let enc = func.encodings[inst];
if enc.is_legal() {
let ctrl_type = func.dfg.ctrl_typevar(inst);
let best_enc = isa.legal_encodings(func, &func.dfg[inst], ctrl_type)
.filter(|e| encinfo.constraints[e.recipe()].satisfied(inst, &divert, &func))
.min_by_key(|e| encinfo.bytes(*e))
.unwrap();
if best_enc != enc {
func.encodings[inst] = best_enc;
dbg!(
"Shrunk [{}] to [{}] in {}, reducing the size from {} to {}",
encinfo.display(enc),
encinfo.display(best_enc),
func.dfg.display_inst(inst, isa),
encinfo.bytes(enc),
encinfo.bytes(best_enc)
);
}
}
divert.apply(&func.dfg[inst]);
}
}
}