tint: Fix transform errors when calling arrayLength() as a statement
Bug: chromium:1360925
Change-Id: If60fa4bb1cf4981c10dd15f8814c0aed70c0066e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/101780
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
diff --git a/src/tint/transform/calculate_array_length.cc b/src/tint/transform/calculate_array_length.cc
index 8edcbf5..b06f7b6 100644
--- a/src/tint/transform/calculate_array_length.cc
+++ b/src/tint/transform/calculate_array_length.cc
@@ -130,6 +130,16 @@
if (builtin->Type() == sem::BuiltinType::kArrayLength) {
// We're dealing with an arrayLength() call
+ if (auto* call_stmt = call->Stmt()->Declaration()->As<ast::CallStatement>()) {
+ if (call_stmt->expr == call_expr) {
+ // arrayLength() is used as a statement.
+ // The argument expression must be side-effect free, so just drop the
+ // statement.
+ RemoveStatement(ctx, call_stmt);
+ continue;
+ }
+ }
+
// A runtime-sized array can only appear as the store type of a variable, or the
// last element of a structure (which cannot itself be nested). Given that we
// require SimplifyPointers, we can assume that the arrayLength() call has one
