diff options
| -rw-r--r-- | src/passes/TupleOptimization.cpp | 16 | ||||
| -rw-r--r-- | test/lit/passes/tuple-optimization.wast | 20 |
2 files changed, 32 insertions, 4 deletions
diff --git a/src/passes/TupleOptimization.cpp b/src/passes/TupleOptimization.cpp index f4fd0910b..e4fb1cf00 100644 --- a/src/passes/TupleOptimization.cpp +++ b/src/passes/TupleOptimization.cpp @@ -125,10 +125,18 @@ struct TupleOptimization : public WalkerPass<PostWalker<TupleOptimization>> { // a get), or a tuple.make. if (auto* tee = value->dynCast<LocalSet>()) { assert(tee->isTee()); - validUses[tee->index]++; - validUses[curr->index]++; - copiedIndexes[tee->index].insert(curr->index); - copiedIndexes[curr->index].insert(tee->index); + // We don't want to count anything as valid if the inner tee is + // unreachable. In that case the outer tee is also unreachable, of + // course, and in fact they might not even have the same tuple type or + // the inner one might not even be a tuple (since we are in unreachable + // code, that is possible). We could try to optimize unreachable tees in + // some cases, but it's simpler to let DCE simplify the code first. + if (tee->type != Type::unreachable) { + validUses[tee->index]++; + validUses[curr->index]++; + copiedIndexes[tee->index].insert(curr->index); + copiedIndexes[curr->index].insert(tee->index); + } } else if (auto* get = value->dynCast<LocalGet>()) { validUses[get->index]++; validUses[curr->index]++; diff --git a/test/lit/passes/tuple-optimization.wast b/test/lit/passes/tuple-optimization.wast index 1788b91e9..766f51e81 100644 --- a/test/lit/passes/tuple-optimization.wast +++ b/test/lit/passes/tuple-optimization.wast @@ -569,6 +569,7 @@ ;; CHECK: (func $unreachability (type $0) ;; CHECK-NEXT: (local $tuple (i32 i32)) + ;; CHECK-NEXT: (local $nontuple f64) ;; CHECK-NEXT: (local.set $tuple ;; CHECK-NEXT: (tuple.make ;; CHECK-NEXT: (i32.const 1) @@ -590,9 +591,17 @@ ;; CHECK-NEXT: ) ;; CHECK-NEXT: ) ;; CHECK-NEXT: ) + ;; CHECK-NEXT: (drop + ;; CHECK-NEXT: (local.tee $tuple + ;; CHECK-NEXT: (local.tee $nontuple + ;; CHECK-NEXT: (unreachable) + ;; CHECK-NEXT: ) + ;; CHECK-NEXT: ) + ;; CHECK-NEXT: ) ;; CHECK-NEXT: ) (func $unreachability (local $tuple (i32 i32)) + (local $nontuple f64) (local.set $tuple (tuple.make (i32.const 1) @@ -615,6 +624,17 @@ ) ) ) + ;; Teeing a nontuple into a tuple is allowed in unreachable code (the input + ;; to the outer tee is simply unreachable, so there is no checking that we + ;; are copying a local into another local of a compatible type). We should + ;; not error here. + (drop + (local.tee $tuple + (local.tee $nontuple + (unreachable) + ) + ) + ) ) ;; CHECK: (func $tee-chain (type $0) |