Rollup merge of #69934 - andjo403:inlinecost, r=wesleywiser

Update the mir inline costs

handle that when mir is lowered to llvm-ir more code is generated.
Landingpads generates 10 llvm-ir instructions
and resume 9 llvm-ir instructions.

r? @wesleywiser
This commit is contained in:
Mazdak Farrokhzad 2020-03-21 08:51:12 +01:00 committed by GitHub
commit 426a4cc930
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@ -22,6 +22,8 @@ const HINT_THRESHOLD: usize = 100;
const INSTR_COST: usize = 5;
const CALL_PENALTY: usize = 25;
const LANDINGPAD_PENALTY: usize = 50;
const RESUME_PENALTY: usize = 45;
const UNKNOWN_SIZE_COST: usize = 10;
@ -325,6 +327,7 @@ impl Inliner<'tcx> {
if ty.needs_drop(tcx, param_env) {
cost += CALL_PENALTY;
if let Some(unwind) = unwind {
cost += LANDINGPAD_PENALTY;
work_list.push(unwind);
}
} else {
@ -340,7 +343,7 @@ impl Inliner<'tcx> {
threshold = 0;
}
TerminatorKind::Call { func: Operand::Constant(ref f), .. } => {
TerminatorKind::Call { func: Operand::Constant(ref f), cleanup, .. } => {
if let ty::FnDef(def_id, _) = f.literal.ty.kind {
// Don't give intrinsics the extra penalty for calls
let f = tcx.fn_sig(def_id);
@ -349,9 +352,21 @@ impl Inliner<'tcx> {
} else {
cost += CALL_PENALTY;
}
} else {
cost += CALL_PENALTY;
}
if cleanup.is_some() {
cost += LANDINGPAD_PENALTY;
}
}
TerminatorKind::Assert { .. } => cost += CALL_PENALTY,
TerminatorKind::Assert { cleanup, .. } => {
cost += CALL_PENALTY;
if cleanup.is_some() {
cost += LANDINGPAD_PENALTY;
}
}
TerminatorKind::Resume => cost += RESUME_PENALTY,
_ => cost += INSTR_COST,
}