diff --git a/src/tools/tidy/src/ui_tests.rs b/src/tools/tidy/src/ui_tests.rs
index 20b8a2c3b24..f582666ab28 100644
--- a/src/tools/tidy/src/ui_tests.rs
+++ b/src/tools/tidy/src/ui_tests.rs
@@ -9,7 +9,7 @@
 
 const ENTRY_LIMIT: usize = 1000;
 // FIXME: The following limits should be reduced eventually.
-const ROOT_ENTRY_LIMIT: usize = 940;
+const ROOT_ENTRY_LIMIT: usize = 881;
 const ISSUES_ENTRY_LIMIT: usize = 1978;
 
 fn check_entries(tests_path: &Path, bad: &mut bool) {
diff --git a/tests/ui/slightly-nice-generic-literal-messages.rs b/tests/ui/generics/slightly-nice-generic-literal-messages.rs
similarity index 100%
rename from tests/ui/slightly-nice-generic-literal-messages.rs
rename to tests/ui/generics/slightly-nice-generic-literal-messages.rs
diff --git a/tests/ui/slightly-nice-generic-literal-messages.stderr b/tests/ui/generics/slightly-nice-generic-literal-messages.stderr
similarity index 100%
rename from tests/ui/slightly-nice-generic-literal-messages.stderr
rename to tests/ui/generics/slightly-nice-generic-literal-messages.stderr
diff --git a/tests/ui/unterminated-comment.rs b/tests/ui/lexer/unterminated-comment.rs
similarity index 100%
rename from tests/ui/unterminated-comment.rs
rename to tests/ui/lexer/unterminated-comment.rs
diff --git a/tests/ui/unterminated-comment.stderr b/tests/ui/lexer/unterminated-comment.stderr
similarity index 100%
rename from tests/ui/unterminated-comment.stderr
rename to tests/ui/lexer/unterminated-comment.stderr
diff --git a/tests/ui/unterminated-nested-comment.rs b/tests/ui/lexer/unterminated-nested-comment.rs
similarity index 100%
rename from tests/ui/unterminated-nested-comment.rs
rename to tests/ui/lexer/unterminated-nested-comment.rs
diff --git a/tests/ui/unterminated-nested-comment.stderr b/tests/ui/lexer/unterminated-nested-comment.stderr
similarity index 100%
rename from tests/ui/unterminated-nested-comment.stderr
rename to tests/ui/lexer/unterminated-nested-comment.stderr
diff --git a/tests/ui/auxiliary/xc-private-method-lib.rs b/tests/ui/privacy/auxiliary/xc-private-method-lib.rs
similarity index 100%
rename from tests/ui/auxiliary/xc-private-method-lib.rs
rename to tests/ui/privacy/auxiliary/xc-private-method-lib.rs
diff --git a/tests/ui/xc-private-method.rs b/tests/ui/privacy/xc-private-method.rs
similarity index 100%
rename from tests/ui/xc-private-method.rs
rename to tests/ui/privacy/xc-private-method.rs
diff --git a/tests/ui/xc-private-method.stderr b/tests/ui/privacy/xc-private-method.stderr
similarity index 100%
rename from tests/ui/xc-private-method.stderr
rename to tests/ui/privacy/xc-private-method.stderr
diff --git a/tests/ui/xc-private-method2.rs b/tests/ui/privacy/xc-private-method2.rs
similarity index 100%
rename from tests/ui/xc-private-method2.rs
rename to tests/ui/privacy/xc-private-method2.rs
diff --git a/tests/ui/xc-private-method2.stderr b/tests/ui/privacy/xc-private-method2.stderr
similarity index 100%
rename from tests/ui/xc-private-method2.stderr
rename to tests/ui/privacy/xc-private-method2.stderr
diff --git a/tests/ui/reachable-unnameable-type-alias.rs b/tests/ui/reachable/reachable-unnameable-type-alias.rs
similarity index 100%
rename from tests/ui/reachable-unnameable-type-alias.rs
rename to tests/ui/reachable/reachable-unnameable-type-alias.rs
diff --git a/tests/ui/disambiguate-identical-names.rs b/tests/ui/resolve/disambiguate-identical-names.rs
similarity index 100%
rename from tests/ui/disambiguate-identical-names.rs
rename to tests/ui/resolve/disambiguate-identical-names.rs
diff --git a/tests/ui/disambiguate-identical-names.stderr b/tests/ui/resolve/disambiguate-identical-names.stderr
similarity index 100%
rename from tests/ui/disambiguate-identical-names.stderr
rename to tests/ui/resolve/disambiguate-identical-names.stderr
diff --git a/tests/ui/thread-local-mutation.rs b/tests/ui/thread-local/thread-local-mutation.rs
similarity index 100%
rename from tests/ui/thread-local-mutation.rs
rename to tests/ui/thread-local/thread-local-mutation.rs
diff --git a/tests/ui/thread-local-mutation.stderr b/tests/ui/thread-local/thread-local-mutation.stderr
similarity index 100%
rename from tests/ui/thread-local-mutation.stderr
rename to tests/ui/thread-local/thread-local-mutation.stderr
diff --git a/tests/ui/thread-local-static.rs b/tests/ui/thread-local/thread-local-static.rs
similarity index 100%
rename from tests/ui/thread-local-static.rs
rename to tests/ui/thread-local/thread-local-static.rs
diff --git a/tests/ui/thread-local-static.stderr b/tests/ui/thread-local/thread-local-static.stderr
similarity index 100%
rename from tests/ui/thread-local-static.stderr
rename to tests/ui/thread-local/thread-local-static.stderr
diff --git a/tests/ui/wrong-mul-method-signature.rs b/tests/ui/traits/wrong-mul-method-signature.rs
similarity index 100%
rename from tests/ui/wrong-mul-method-signature.rs
rename to tests/ui/traits/wrong-mul-method-signature.rs
diff --git a/tests/ui/wrong-mul-method-signature.stderr b/tests/ui/traits/wrong-mul-method-signature.stderr
similarity index 100%
rename from tests/ui/wrong-mul-method-signature.stderr
rename to tests/ui/traits/wrong-mul-method-signature.stderr
diff --git a/tests/ui/tuple-index.rs b/tests/ui/tuple/tuple-index.rs
similarity index 100%
rename from tests/ui/tuple-index.rs
rename to tests/ui/tuple/tuple-index.rs
diff --git a/tests/ui/output-type-mismatch.rs b/tests/ui/typeck/output-type-mismatch.rs
similarity index 100%
rename from tests/ui/output-type-mismatch.rs
rename to tests/ui/typeck/output-type-mismatch.rs
diff --git a/tests/ui/output-type-mismatch.stderr b/tests/ui/typeck/output-type-mismatch.stderr
similarity index 100%
rename from tests/ui/output-type-mismatch.stderr
rename to tests/ui/typeck/output-type-mismatch.stderr
diff --git a/tests/ui/suppressed-error.rs b/tests/ui/typeck/suppressed-error.rs
similarity index 100%
rename from tests/ui/suppressed-error.rs
rename to tests/ui/typeck/suppressed-error.rs
diff --git a/tests/ui/suppressed-error.stderr b/tests/ui/typeck/suppressed-error.stderr
similarity index 100%
rename from tests/ui/suppressed-error.stderr
rename to tests/ui/typeck/suppressed-error.stderr
diff --git a/tests/ui/tag-that-dare-not-speak-its-name.rs b/tests/ui/typeck/tag-that-dare-not-speak-its-name.rs
similarity index 100%
rename from tests/ui/tag-that-dare-not-speak-its-name.rs
rename to tests/ui/typeck/tag-that-dare-not-speak-its-name.rs
diff --git a/tests/ui/tag-that-dare-not-speak-its-name.stderr b/tests/ui/typeck/tag-that-dare-not-speak-its-name.stderr
similarity index 100%
rename from tests/ui/tag-that-dare-not-speak-its-name.stderr
rename to tests/ui/typeck/tag-that-dare-not-speak-its-name.stderr
diff --git a/tests/ui/terr-in-field.rs b/tests/ui/typeck/terr-in-field.rs
similarity index 100%
rename from tests/ui/terr-in-field.rs
rename to tests/ui/typeck/terr-in-field.rs
diff --git a/tests/ui/terr-in-field.stderr b/tests/ui/typeck/terr-in-field.stderr
similarity index 100%
rename from tests/ui/terr-in-field.stderr
rename to tests/ui/typeck/terr-in-field.stderr
diff --git a/tests/ui/terr-sorts.rs b/tests/ui/typeck/terr-sorts.rs
similarity index 100%
rename from tests/ui/terr-sorts.rs
rename to tests/ui/typeck/terr-sorts.rs
diff --git a/tests/ui/terr-sorts.stderr b/tests/ui/typeck/terr-sorts.stderr
similarity index 100%
rename from tests/ui/terr-sorts.stderr
rename to tests/ui/typeck/terr-sorts.stderr
diff --git a/tests/ui/while-type-error.rs b/tests/ui/typeck/while-type-error.rs
similarity index 100%
rename from tests/ui/while-type-error.rs
rename to tests/ui/typeck/while-type-error.rs
diff --git a/tests/ui/while-type-error.stderr b/tests/ui/typeck/while-type-error.stderr
similarity index 100%
rename from tests/ui/while-type-error.stderr
rename to tests/ui/typeck/while-type-error.stderr
diff --git a/tests/ui/wrong-ret-type.rs b/tests/ui/typeck/wrong-ret-type.rs
similarity index 100%
rename from tests/ui/wrong-ret-type.rs
rename to tests/ui/typeck/wrong-ret-type.rs
diff --git a/tests/ui/wrong-ret-type.stderr b/tests/ui/typeck/wrong-ret-type.stderr
similarity index 100%
rename from tests/ui/wrong-ret-type.stderr
rename to tests/ui/typeck/wrong-ret-type.stderr
diff --git a/tests/ui/ufcs-polymorphic-paths.rs b/tests/ui/ufcs/ufcs-polymorphic-paths.rs
similarity index 100%
rename from tests/ui/ufcs-polymorphic-paths.rs
rename to tests/ui/ufcs/ufcs-polymorphic-paths.rs
diff --git a/tests/ui/expr-block-generic-unique1.rs b/tests/ui/unique/expr-block-generic-unique1.rs
similarity index 100%
rename from tests/ui/expr-block-generic-unique1.rs
rename to tests/ui/unique/expr-block-generic-unique1.rs
diff --git a/tests/ui/expr-block-generic-unique2.rs b/tests/ui/unique/expr-block-generic-unique2.rs
similarity index 100%
rename from tests/ui/expr-block-generic-unique2.rs
rename to tests/ui/unique/expr-block-generic-unique2.rs
diff --git a/tests/ui/expr-if-unique.rs b/tests/ui/unique/expr-if-unique.rs
similarity index 100%
rename from tests/ui/expr-if-unique.rs
rename to tests/ui/unique/expr-if-unique.rs
diff --git a/tests/ui/unique-object-noncopyable.rs b/tests/ui/unique/unique-object-noncopyable.rs
similarity index 100%
rename from tests/ui/unique-object-noncopyable.rs
rename to tests/ui/unique/unique-object-noncopyable.rs
diff --git a/tests/ui/unique-object-noncopyable.stderr b/tests/ui/unique/unique-object-noncopyable.stderr
similarity index 100%
rename from tests/ui/unique-object-noncopyable.stderr
rename to tests/ui/unique/unique-object-noncopyable.stderr
diff --git a/tests/ui/unique-pinned-nocopy.rs b/tests/ui/unique/unique-pinned-nocopy.rs
similarity index 100%
rename from tests/ui/unique-pinned-nocopy.rs
rename to tests/ui/unique/unique-pinned-nocopy.rs
diff --git a/tests/ui/unique-pinned-nocopy.stderr b/tests/ui/unique/unique-pinned-nocopy.stderr
similarity index 100%
rename from tests/ui/unique-pinned-nocopy.stderr
rename to tests/ui/unique/unique-pinned-nocopy.stderr
diff --git a/tests/ui/unwind-unique.rs b/tests/ui/unique/unwind-unique.rs
similarity index 100%
rename from tests/ui/unwind-unique.rs
rename to tests/ui/unique/unwind-unique.rs
diff --git a/tests/ui/mir-unpretty.rs b/tests/ui/unpretty/mir-unpretty.rs
similarity index 100%
rename from tests/ui/mir-unpretty.rs
rename to tests/ui/unpretty/mir-unpretty.rs
diff --git a/tests/ui/mir-unpretty.stderr b/tests/ui/unpretty/mir-unpretty.stderr
similarity index 100%
rename from tests/ui/mir-unpretty.stderr
rename to tests/ui/unpretty/mir-unpretty.stderr
diff --git a/tests/ui/unpretty-expr-fn-arg.rs b/tests/ui/unpretty/unpretty-expr-fn-arg.rs
similarity index 100%
rename from tests/ui/unpretty-expr-fn-arg.rs
rename to tests/ui/unpretty/unpretty-expr-fn-arg.rs
diff --git a/tests/ui/unpretty-expr-fn-arg.stdout b/tests/ui/unpretty/unpretty-expr-fn-arg.stdout
similarity index 100%
rename from tests/ui/unpretty-expr-fn-arg.stdout
rename to tests/ui/unpretty/unpretty-expr-fn-arg.stdout
diff --git a/tests/ui/foreign-unsafe-fn-called.mir.stderr b/tests/ui/unsafe/foreign-unsafe-fn-called.mir.stderr
similarity index 100%
rename from tests/ui/foreign-unsafe-fn-called.mir.stderr
rename to tests/ui/unsafe/foreign-unsafe-fn-called.mir.stderr
diff --git a/tests/ui/foreign-unsafe-fn-called.rs b/tests/ui/unsafe/foreign-unsafe-fn-called.rs
similarity index 100%
rename from tests/ui/foreign-unsafe-fn-called.rs
rename to tests/ui/unsafe/foreign-unsafe-fn-called.rs
diff --git a/tests/ui/foreign-unsafe-fn-called.thir.stderr b/tests/ui/unsafe/foreign-unsafe-fn-called.thir.stderr
similarity index 100%
rename from tests/ui/foreign-unsafe-fn-called.thir.stderr
rename to tests/ui/unsafe/foreign-unsafe-fn-called.thir.stderr
diff --git a/tests/ui/new-unsafe-pointers.rs b/tests/ui/unsafe/new-unsafe-pointers.rs
similarity index 100%
rename from tests/ui/new-unsafe-pointers.rs
rename to tests/ui/unsafe/new-unsafe-pointers.rs
diff --git a/tests/ui/unsafe-fn-called-from-unsafe-blk.rs b/tests/ui/unsafe/unsafe-fn-called-from-unsafe-blk.rs
similarity index 100%
rename from tests/ui/unsafe-fn-called-from-unsafe-blk.rs
rename to tests/ui/unsafe/unsafe-fn-called-from-unsafe-blk.rs
diff --git a/tests/ui/unsafe-fn-called-from-unsafe-fn.rs b/tests/ui/unsafe/unsafe-fn-called-from-unsafe-fn.rs
similarity index 100%
rename from tests/ui/unsafe-fn-called-from-unsafe-fn.rs
rename to tests/ui/unsafe/unsafe-fn-called-from-unsafe-fn.rs
diff --git a/tests/ui/unsafe-pointer-assignability.rs b/tests/ui/unsafe/unsafe-pointer-assignability.rs
similarity index 100%
rename from tests/ui/unsafe-pointer-assignability.rs
rename to tests/ui/unsafe/unsafe-pointer-assignability.rs
diff --git a/tests/ui/variance-intersection-of-ref-and-opt-ref.rs b/tests/ui/variance/variance-intersection-of-ref-and-opt-ref.rs
similarity index 100%
rename from tests/ui/variance-intersection-of-ref-and-opt-ref.rs
rename to tests/ui/variance/variance-intersection-of-ref-and-opt-ref.rs
diff --git a/tests/ui/variance-iterators-in-libcore.rs b/tests/ui/variance/variance-iterators-in-libcore.rs
similarity index 100%
rename from tests/ui/variance-iterators-in-libcore.rs
rename to tests/ui/variance/variance-iterators-in-libcore.rs
diff --git a/tests/ui/wasm-custom-section-relocations.rs b/tests/ui/wasm/wasm-custom-section-relocations.rs
similarity index 100%
rename from tests/ui/wasm-custom-section-relocations.rs
rename to tests/ui/wasm/wasm-custom-section-relocations.rs
diff --git a/tests/ui/wasm-custom-section-relocations.stderr b/tests/ui/wasm/wasm-custom-section-relocations.stderr
similarity index 100%
rename from tests/ui/wasm-custom-section-relocations.stderr
rename to tests/ui/wasm/wasm-custom-section-relocations.stderr