bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Simplify assume of a constant.

Browse source
This commit is contained in:
Camille GILLOT 2023-07-22 15:34:22 +00:00
parent c748ac1f11
commit 0b13e636f5
6 changed files with 80 additions and 85 deletions
Download patch file Download diff file Expand all files Collapse all files

19
compiler/rustc_mir_transform/src/simplify_branches.rs
View file

@ -16,8 +16,25 @@ impl<'tcx> MirPass<'tcx> for SimplifyConstCondition {
}
fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
trace!("Running SimplifyConstCondition on {:?}", body.source);
let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
for block in body.basic_blocks_mut() {
'blocks: for block in body.basic_blocks_mut() {
for stmt in block.statements.iter_mut() {
if let StatementKind::Intrinsic(box ref intrinsic) = stmt.kind
&& let NonDivergingIntrinsic::Assume(discr) = intrinsic
&& let Operand::Constant(ref c) = discr
&& let Some(constant) = c.const_.try_eval_bool(tcx, param_env)
{
if constant {
stmt.make_nop();
} else {
block.statements.clear();
block.terminator_mut().kind = TerminatorKind::Unreachable;
continue 'blocks;
}
}
}
let terminator = block.terminator_mut();
terminator.kind = match terminator.kind {
TerminatorKind::SwitchInt {