diff options
| -rw-r--r-- | src/passes/OptimizeInstructions.cpp | 8 | ||||
| -rw-r--r-- | test/lit/passes/inlining_vacuum_optimize-instructions.wast | 43 |
2 files changed, 50 insertions, 1 deletions
diff --git a/src/passes/OptimizeInstructions.cpp b/src/passes/OptimizeInstructions.cpp index 3de7b6519..f96d4d30a 100644 --- a/src/passes/OptimizeInstructions.cpp +++ b/src/passes/OptimizeInstructions.cpp @@ -1769,7 +1769,13 @@ struct OptimizeInstructions } void visitRefCast(RefCast* curr) { - if (curr->type == Type::unreachable) { + // Note we must check the ref's type here and not our own, since we only + // refinalize at the end, which means our type may not have been updated yet + // after a change in the child. + // TODO: we could update unreachability up the stack perhaps, or just move + // all patterns that can add unreachability to a pass that does so + // already like vacuum or dce. + if (curr->ref->type == Type::unreachable) { return; } diff --git a/test/lit/passes/inlining_vacuum_optimize-instructions.wast b/test/lit/passes/inlining_vacuum_optimize-instructions.wast new file mode 100644 index 000000000..839a5887e --- /dev/null +++ b/test/lit/passes/inlining_vacuum_optimize-instructions.wast @@ -0,0 +1,43 @@ +;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited. + +;; RUN: wasm-opt %s --inlining --vacuum --optimize-instructions -all -S -o - | filecheck %s + +;; Check for a specific bug involving inlining first turning a struct.get's +;; input into a null, then vacuum gets rid of intervening blocks, and then +;; optimize-instructions runs into the following situation: first it turns the +;; struct.get of a null into an unreachable, then it makes a note to itself to +;; refinalize at the end, but before the end it tries to optimize the ref.cast. +;; The ref.cast's type has not been updated to unreachable yet, but its ref has, +;; which is temporarily inconsistent. We must be careful to avoid confusion +;; there. +(module + ;; CHECK: (type $B (struct )) + + ;; CHECK: (type $ref?|$A|_=>_none (func (param (ref null $A)))) + + ;; CHECK: (type $A (struct (field (ref null $B)))) + (type $A (struct_subtype (field (ref null $B)) data)) + (type $B (struct_subtype data)) + ;; CHECK: (func $target (param $0 (ref null $A)) + ;; CHECK-NEXT: (drop + ;; CHECK-NEXT: (ref.cast_static $B + ;; CHECK-NEXT: (unreachable) + ;; CHECK-NEXT: ) + ;; CHECK-NEXT: ) + ;; CHECK-NEXT: (unreachable) + ;; CHECK-NEXT: ) + (func $target (param $0 (ref null $A)) + (drop + (ref.cast_static $B + (struct.get $A 0 + (call $get-null) + ) + ) + ) + (unreachable) + ) + (func $get-null (result (ref null $A)) + (ref.null none) + ) +) + |