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authorRalf Jung <post@ralfj.de>2024-03-24 12:53:03 +0100
committerRalf Jung <post@ralfj.de>2024-03-24 12:53:03 +0100
commit42526e142aa697db9391c7df0810ca4a4f73a164 (patch)
tree56a41fb0cebc07feef737e9140c6f9261900545c
parent548e14b43963882fb758deb89e8258d9b8c2fc2a (diff)
downloadrust-42526e142aa697db9391c7df0810ca4a4f73a164.tar.gz
rust-42526e142aa697db9391c7df0810ca4a4f73a164.zip
simplify_branches: add comment
-rw-r--r--compiler/rustc_mir_transform/src/simplify_branches.rs1
1 files changed, 1 insertions, 0 deletions
diff --git a/compiler/rustc_mir_transform/src/simplify_branches.rs b/compiler/rustc_mir_transform/src/simplify_branches.rs
index 35a052166bd..c746041ebd8 100644
--- a/compiler/rustc_mir_transform/src/simplify_branches.rs
+++ b/compiler/rustc_mir_transform/src/simplify_branches.rs
@@ -19,6 +19,7 @@ impl<'tcx> MirPass<'tcx> for SimplifyConstCondition {
         let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
         'blocks: for block in body.basic_blocks_mut() {
             for stmt in block.statements.iter_mut() {
+                // Simplify `assume` of a known value: either a NOP or unreachable.
                 if let StatementKind::Intrinsic(box ref intrinsic) = stmt.kind
                     && let NonDivergingIntrinsic::Assume(discr) = intrinsic
                     && let Operand::Constant(ref c) = discr