update br type when turning it into a br_if in remove-unused-brs

7 files changed, 112 insertions, 0 deletions

diff --git a/src/passes/RemoveUnusedBrs.cpp b/src/passes/RemoveUnusedBrs.cpp
index 8b7611ec9..86a46374f 100644
--- a/src/passes/RemoveUnusedBrs.cpp
+++ b/src/passes/RemoveUnusedBrs.cpp
@@ -149,6 +149,7 @@ struct RemoveUnusedBrs : public WalkerPass<PostWalker<RemoveUnusedBrs, Visitor<R
         // if the br has a value, then if => br_if means we always execute the value, and also the order is value,condition vs condition,value
         if (canTurnIfIntoBrIf(curr->condition, br->value)) {
           br->condition = curr->condition;
+          br->finalize();
           replaceCurrent(br);
           anotherCycle = true;
         }
@@ -408,6 +409,7 @@ struct RemoveUnusedBrs : public WalkerPass<PostWalker<RemoveUnusedBrs, Visitor<R
             // we are an if-else where the ifTrue is a break without a condition, so we can do this
             list[i] = ifTrueBreak;
             ifTrueBreak->condition = iff->condition;
+            ifTrueBreak->finalize();
             ExpressionManipulator::spliceIntoBlock(curr, i + 1, iff->ifFalse);
             continue;
           }
@@ -416,6 +418,7 @@ struct RemoveUnusedBrs : public WalkerPass<PostWalker<RemoveUnusedBrs, Visitor<R
           if (ifFalseBreak && !ifFalseBreak->condition && canTurnIfIntoBrIf(iff->condition, ifFalseBreak->value)) {
             list[i] = ifFalseBreak;
             ifFalseBreak->condition = Builder(*getModule()).makeUnary(EqZInt32, iff->condition);
+            ifFalseBreak->finalize();
             ExpressionManipulator::spliceIntoBlock(curr, i + 1, iff->ifTrue);
             continue;
           }
diff --git a/src/wasm.h b/src/wasm.h
index d6bdfe91f..ca3c8e5f5 100644
--- a/src/wasm.h
+++ b/src/wasm.h
@@ -1027,6 +1027,8 @@ public:
   void finalize() {
     if (condition) {
       type = none;
+    } else {
+      type = unreachable;
     }
   }
 };
diff --git a/test/unit.asm.js b/test/unit.asm.js
index 5833d2fd8..0decc886c 100644
--- a/test/unit.asm.js
+++ b/test/unit.asm.js
@@ -540,6 +540,23 @@ function asm(global, env, buffer) {
    }
   }
 
+  function __Z12multi_varargiz($0) {
+   $0 = $0|0;
+   var $2 = 0, $$06$i4 = 0, $exitcond$i6 = 0, $12 = 0, $20 = 0;
+   if ($2) {
+    while(1) {
+     $12 = $$06$i4;
+     if ($exitcond$i6) {
+      break;
+     } else {
+      $$06$i4 = $20;
+     }
+    }
+   } else {
+    lb(1) | 0; // returns a value, and the while is unreachable
+   }
+  }
+
   var FUNCTION_TABLE_a = [ z, big_negative, z, z ];
   var FUNCTION_TABLE_b = [ w, w, importedDoubles, w ];
   var FUNCTION_TABLE_c = [ z, cneg ];
diff --git a/test/unit.fromasm b/test/unit.fromasm
index 77e5a9eb1..773cbbd9d 100644
--- a/test/unit.fromasm
+++ b/test/unit.fromasm
@@ -990,4 +990,21 @@
       (br $while-in$1)
     )
   )
+  (func $__Z12multi_varargiz (param $0 i32)
+    (local $1 i32)
+    (local $2 i32)
+    (if
+      (get_local $1)
+      (loop $while-in$1
+        (br_if $while-in$1
+          (i32.eqz
+            (get_local $2)
+          )
+        )
+      )
+      (call $lb
+        (i32.const 1)
+      )
+    )
+  )
 )
diff --git a/test/unit.fromasm.imprecise b/test/unit.fromasm.imprecise
index 35aa3e4f3..80e34dfb9 100644
--- a/test/unit.fromasm.imprecise
+++ b/test/unit.fromasm.imprecise
@@ -971,4 +971,21 @@
       (br $while-in$1)
     )
   )
+  (func $__Z12multi_varargiz (param $0 i32)
+    (local $1 i32)
+    (local $2 i32)
+    (if
+      (get_local $1)
+      (loop $while-in$1
+        (br_if $while-in$1
+          (i32.eqz
+            (get_local $2)
+          )
+        )
+      )
+      (call $lb
+        (i32.const 1)
+      )
+    )
+  )
 )
diff --git a/test/unit.fromasm.imprecise.no-opts b/test/unit.fromasm.imprecise.no-opts
index 7808b6cf2..3e532ef2a 100644
--- a/test/unit.fromasm.imprecise.no-opts
+++ b/test/unit.fromasm.imprecise.no-opts
@@ -1549,4 +1549,32 @@
       )
     )
   )
+  (func $__Z12multi_varargiz (param $$0 i32)
+    (local $$2 i32)
+    (local $$$06$i4 i32)
+    (local $$exitcond$i6 i32)
+    (local $$12 i32)
+    (local $$20 i32)
+    (if
+      (get_local $$2)
+      (loop $while-in$1
+        (block $while-out$0
+          (set_local $$12
+            (get_local $$$06$i4)
+          )
+          (if
+            (get_local $$exitcond$i6)
+            (br $while-out$0)
+            (set_local $$$06$i4
+              (get_local $$20)
+            )
+          )
+          (br $while-in$1)
+        )
+      )
+      (call $lb
+        (i32.const 1)
+      )
+    )
+  )
 )
diff --git a/test/unit.fromasm.no-opts b/test/unit.fromasm.no-opts
index 22528323a..d2c1beec7 100644
--- a/test/unit.fromasm.no-opts
+++ b/test/unit.fromasm.no-opts
@@ -1555,4 +1555,32 @@
       )
     )
   )
+  (func $__Z12multi_varargiz (param $$0 i32)
+    (local $$2 i32)
+    (local $$$06$i4 i32)
+    (local $$exitcond$i6 i32)
+    (local $$12 i32)
+    (local $$20 i32)
+    (if
+      (get_local $$2)
+      (loop $while-in$1
+        (block $while-out$0
+          (set_local $$12
+            (get_local $$$06$i4)
+          )
+          (if
+            (get_local $$exitcond$i6)
+            (br $while-out$0)
+            (set_local $$$06$i4
+              (get_local $$20)
+            )
+          )
+          (br $while-in$1)
+        )
+      )
+      (call $lb
+        (i32.const 1)
+      )
+    )
+  )
 )