Add feature flags and validation to wasm-metadce (#2364)

Sometimes wasm-metadce is the last tool to run over a binary in
Emscripten, and in that case it needs to know what features are
enabled in order to emit a valid binary. For example it needs to know
whether to emit a data count section.

3 files changed, 16 insertions, 2 deletions

diff --git a/test/metadce/all-outside.wast b/test/metadce/all-outside.wast
index f84d2580e..3af8f2545 100644
--- a/test/metadce/all-outside.wast
+++ b/test/metadce/all-outside.wast
@@ -1,2 +1 @@
 (module)
-
diff --git a/test/metadce/spanning_cycle.wast b/test/metadce/spanning_cycle.wast
index 83a1c786f..cfb74346a 100644
--- a/test/metadce/spanning_cycle.wast
+++ b/test/metadce/spanning_cycle.wast
@@ -1,10 +1,18 @@
 (module
+ (memory 1 1)
+ (data passive "Hello, datacount section!")
+
  (import "env" "js_func" (func $a_js_func))
 
  (export "wasm_func_a" (func $a_wasm_func))
 
  (func $a_wasm_func
+  ;; refer to the data segment to keep it around
+  (memory.init 0
+   (i32.const 0)
+   (i32.const 0)
+   (i32.const 25)
+  )
   (call $a_js_func)
  )
 )
-
diff --git a/test/metadce/spanning_cycle.wast.dced b/test/metadce/spanning_cycle.wast.dced
index 74c4eb4a5..3782d20fd 100644
--- a/test/metadce/spanning_cycle.wast.dced
+++ b/test/metadce/spanning_cycle.wast.dced
@@ -1,8 +1,15 @@
 (module
  (type $FUNCSIG$v (func))
  (import "env" "js_func" (func $a_js_func))
+ (memory $0 1 1)
+ (data passive "Hello, datacount section!")
  (export "wasm_func_a" (func $a_wasm_func))
  (func $a_wasm_func (; 1 ;) (type $FUNCSIG$v)
+  (memory.init 0
+   (i32.const 0)
+   (i32.const 0)
+   (i32.const 25)
+  )
   (call $a_js_func)
  )
 )