1 files changed, 106 insertions, 0 deletions
diff --git a/test/lit/binary/dwarf-multivalue.test b/test/lit/binary/dwarf-multivalue.test
new file mode 100644
index 000000000..435aebe25
--- /dev/null
+++ b/test/lit/binary/dwarf-multivalue.test
@@ -0,0 +1,106 @@
+;; Test that we handle multivalue + DWARF correctly. When we need to preserve
+;; DWARF info, we don't do any local reordering and all newly added locals
+;; during parsing/writing are added at the end of the local list.
+
+;; Generated from this c file with the following command:
+;; $ emcc -g -Xclang -target-abi -Xclang experimental-mv dwarf-multivalue.c -o dwarf-multivalue.wasm
+;;
+;; struct MyStruct {
+;;   int a;
+;;   float b;
+;; };
+;;
+;; struct MyStruct foo() {
+;;   struct MyStruct ret = {.a = 3, .b = 3.5};
+;;   return ret;
+;; }
+;;
+;; void test() {
+;;   struct MyStruct s = foo();
+;; }
+;;
+;; int main() {
+;;   test();
+;;   return 0;
+;; }
+
+;; The original wasm file's $test function's locals are as follows:
+;; (func $test
+;;  (local $0 i32)
+;;  (local $1 i32)
+;;  (local $2 i32)
+;;  (local $3 i32)
+;;  (local $4 f32)
+;;  (local $5 i32)
+;;  (local $6 i32)
+;;  (local $7 i32)
+;;  (local $8 f32)
+;;  (local $9 i32)
+;;  (local $10 f32)
+
+;; If we parse this wasm file into Binaryen IR, two locals are added in the
+;; process. Here $11 is added for tuple parsing and $12 is added for stacky IR
+;; resolving during binary reading process.
+;; RUN: wasm-dis %s.wasm -o - | filecheck %s --check-prefix=ORIG
+;; ORIG:      (func $test
+;; ORIG-NEXT:  (local $0 i32)
+;; ORIG-NEXT:  (local $1 i32)
+;; ORIG-NEXT:  (local $2 i32)
+;; ORIG-NEXT:  (local $3 i32)
+;; ORIG-NEXT:  (local $4 f32)
+;; ORIG-NEXT:  (local $5 i32)
+;; ORIG-NEXT:  (local $6 i32)
+;; ORIG-NEXT:  (local $7 i32)
+;; ORIG-NEXT:  (local $8 f32)
+;; ORIG-NEXT:  (local $9 i32)
+;; ORIG-NEXT:  (local $10 f32)
+;; ORIG-NEXT:  (local $11 (tuple i32 f32))
+;; ORIG-NEXT:  (local $12 i32)
+
+;; If we write this IR into binary, even if this cannot be displayed in the wast
+;; format, the local order of $test will look like this, because we don't
+;; reorder locals:
+;; (func $test
+;;  (local $0 i32)
+;;  (local $1 i32)
+;;  (local $2 i32)
+;;  (local $3 i32)
+;;  (local $4 f32)
+;;  (local $5 i32)
+;;  (local $6 i32)
+;;  (local $7 i32)
+;;  (local $8 f32)
+;;  (local $9 i32)
+;;  (local $10 f32)
+;;  (local $11 i32) ;; Previous (local $11 (tuple i32 f32))'s first element
+;;  (local $12 f32) ;; Previous (local $11 (tuple i32 f32))'s second element
+;;  (local $13 i32) ;; Previous (local $12 i32)
+;;  (local $14 f32) ;; scratch local for f32
+
+;; We parse this binary again into Binaryen IR, roundtripping the original
+;; binary. Here until (local $14) is the same with the previous list, and $15 is
+;; is added for tuple parsing and $16 is added for stacky IR resolving during
+;; binary reading process.
+;; RUN: wasm-opt -all -g --roundtrip %s.wasm -S -o - | filecheck %s --check-prefix=ROUNDTRIP
+;; ROUNDTRIP:      (func $test
+;; ROUNDTRIP-NEXT:  (local $0 i32)
+;; ROUNDTRIP-NEXT:  (local $1 i32)
+;; ROUNDTRIP-NEXT:  (local $2 i32)
+;; ROUNDTRIP-NEXT:  (local $3 i32)
+;; ROUNDTRIP-NEXT:  (local $4 f32)
+;; ROUNDTRIP-NEXT:  (local $5 i32)
+;; ROUNDTRIP-NEXT:  (local $6 i32)
+;; ROUNDTRIP-NEXT:  (local $7 i32)
+;; ROUNDTRIP-NEXT:  (local $8 f32)
+;; ROUNDTRIP-NEXT:  (local $9 i32)
+;; ROUNDTRIP-NEXT:  (local $10 f32)
+;; ROUNDTRIP-NEXT:  (local $11 i32)
+;; ROUNDTRIP-NEXT:  (local $12 f32)
+;; ROUNDTRIP-NEXT:  (local $13 i32)
+;; ROUNDTRIP-NEXT:  (local $14 f32)
+;; ROUNDTRIP-NEXT:  (local $15 (tuple i32 f32))
+;; ROUNDTRIP-NEXT:  (local $16 i32)
+
+;; We can see that we don't reorder the locals during the process and the
+;; original list of locals, local $0~$10, is untouched, to NOT invalidate DWARF
+;; info.