remove condition from break

5 files changed, 66 insertions, 39 deletions

diff --git a/src/asm2wasm.h b/src/asm2wasm.h
index 356077460..3a8d3d579 100644
--- a/src/asm2wasm.h
+++ b/src/asm2wasm.h
@@ -836,7 +836,6 @@ Function* Asm2WasmBuilder::processFunction(Ref ast) {
       needTopmost = true;
       auto ret = allocator.alloc<Break>();
       ret->name = TOPMOST;
-      ret->condition = nullptr;
       ret->value = !!ast[1] ? process(ast[1]) : nullptr;
       return ret;
     } else if (what == BLOCK) {
@@ -845,14 +844,12 @@ Function* Asm2WasmBuilder::processFunction(Ref ast) {
       auto ret = allocator.alloc<Break>();
       assert(breakStack.size() > 0);
       ret->name = !!ast[1] ? getBreakLabelName(ast[1]->getIString()) : breakStack.back();
-      ret->condition = nullptr;
       ret->value = nullptr;
       return ret;
     } else if (what == CONTINUE) {
       auto ret = allocator.alloc<Break>();
       assert(continueStack.size() > 0);
       ret->name = !!ast[1] ? getContinueLabelName(ast[1]->getIString()) : continueStack.back();
-      ret->condition = nullptr;
       ret->value = nullptr;
       return ret;
     } else if (what == WHILE) {
@@ -874,12 +871,15 @@ Function* Asm2WasmBuilder::processFunction(Ref ast) {
       if (forever) {
         ret->body = process(ast[2]);
       } else {
-        Break *continueWhile = allocator.alloc<Break>();
-        continueWhile->name = in;
-        continueWhile->condition = process(ast[1]);
-        continueWhile->value = nullptr;
+        Break *breakOut = allocator.alloc<Break>();
+        breakOut->name = in;
+        breakOut->value = nullptr;
+        If *condition = allocator.alloc<If>();
+        condition->condition = process(ast[1]);
+        condition->ifTrue = breakOut;
+        condition->ifFalse = nullptr;
         auto body = allocator.alloc<Block>();
-        body->list.push_back(continueWhile);
+        body->list.push_back(condition);
         body->list.push_back(process(ast[2]));
         ret->body = body;
       }
@@ -923,16 +923,19 @@ Function* Asm2WasmBuilder::processFunction(Ref ast) {
       ret->body = process(ast[2]);
       continueStack.pop_back();
       breakStack.pop_back();
-      Break *continueIf = allocator.alloc<Break>();
-      continueIf->name = in;
-      continueIf->condition = process(ast[1]);
-      continueIf->value = nullptr;
+      Break *continueIn = allocator.alloc<Break>();
+      continueIn->name = in;
+      continueIn->value = nullptr;
+      If *condition = allocator.alloc<If>();
+      condition->condition = process(ast[1]);
+      condition->ifTrue = continueIn;
+      condition->ifFalse = nullptr;
       if (Block *block = ret->body->dyn_cast<Block>()) {
-        block->list.push_back(continueIf);
+        block->list.push_back(condition);
       } else {
         auto newBody = allocator.alloc<Block>();
         newBody->list.push_back(ret->body);
-        newBody->list.push_back(continueIf);
+        newBody->list.push_back(condition);
         ret->body = newBody;
       }
       return ret;
@@ -1054,7 +1057,6 @@ void Asm2WasmBuilder::optimize() {
 
       // look in the child's children to see if there are more uses of this name
       BreakSeeker breakSeeker(curr->name);
-      breakSeeker.walk(child->condition);
       breakSeeker.walk(child->value);
       if (breakSeeker.found == 0) return child->value;
 
diff --git a/src/wasm-interpreter.h b/src/wasm-interpreter.h
index 7356c6b64..a18289c5b 100644
--- a/src/wasm-interpreter.h
+++ b/src/wasm-interpreter.h
@@ -123,11 +123,6 @@ public:
       }
       Flow visitBreak(Break *curr) override {
         NOTE_VISIT("Break");
-        if (curr->condition) {
-          Flow flow = visit(curr->condition);
-          if (flow.breaking()) return flow;
-          if (!flow.value.geti32()) return Flow();
-        }
         if (curr->value) {
           Flow flow = visit(curr->value);
           if (!flow.breaking()) {
diff --git a/src/wasm.h b/src/wasm.h
index 3deae22ef..222eb7cfa 100644
--- a/src/wasm.h
+++ b/src/wasm.h
@@ -387,12 +387,11 @@ public:
   Break() : Expression(BreakId) {}
 
   Name name;
-  Expression *condition, *value;
+  Expression *value;
 
   std::ostream& doPrint(std::ostream &o, unsigned indent) {
     printOpening(o, "break ") << name;
     incIndent(o, indent);
-    if (condition) printFullLine(o, indent, condition);
     if (value) printFullLine(o, indent, value);
     return decIndent(o, indent);
   }
@@ -1039,7 +1038,6 @@ struct WasmWalker : public WasmVisitor<Expression*> {
       }
       void visitLabel(Label *curr) override {}
       void visitBreak(Break *curr) override {
-        curr->condition = parent.walk(curr->condition);
         curr->value = parent.walk(curr->value);
       }
       void visitSwitch(Switch *curr) override {
diff --git a/test/emcc_O2_hello_world.wast b/test/emcc_O2_hello_world.wast
index 1b3ff0336..777bcc9d0 100644
--- a/test/emcc_O2_hello_world.wast
+++ b/test/emcc_O2_hello_world.wast
@@ -4654,11 +4654,13 @@
                         )
                       )
                     )
-                    (break $do-in$29
+                    (if
                       (i32.ne
                         (get_local $i63)
                         (i32.const 0)
                       )
+                      (break $do-in$29
+                      )
                     )
                   )
                 )
@@ -6677,7 +6679,7 @@
                       (get_local $i63)
                       (i32.const 7)
                     )
-                    (break $do-in$47
+                    (if
                       (i32.lt_u
                         (i32.shr_u
                           (i32.add
@@ -6691,6 +6693,8 @@
                           (i32.const 0)
                         )
                       )
+                      (break $do-in$47
+                      )
                     )
                   )
                 )
@@ -7379,11 +7383,13 @@
                         (i32.const 1)
                       )
                     )
-                    (break $do-in$51
+                    (if
                       (i32.ne
                         (get_local $i5)
                         (i32.const 32)
                       )
+                      (break $do-in$51
+                      )
                     )
                   )
                 )
@@ -11450,11 +11456,13 @@
         (block
           (loop $while-out$0 $while-in$1
             (block
-              (break $while-in$1
+              (if
                 (i32.and
                   (get_local $i1)
                   (i32.const 3)
                 )
+                (break $while-in$1
+                )
               )
               (block
                 (if
@@ -11495,11 +11503,13 @@
           )
           (loop $while-out$2 $while-in$3
             (block
-              (break $while-in$3
+              (if
                 (i32.ge_s
                   (get_local $i3)
                   (i32.const 4)
                 )
+                (break $while-in$3
+                )
               )
               (block
                 (i32.store align=4
@@ -11533,11 +11543,13 @@
       )
       (loop $while-out$4 $while-in$5
         (block
-          (break $while-in$5
+          (if
             (i32.gt_s
               (get_local $i3)
               (i32.const 0)
             )
+            (break $while-in$5
+            )
           )
           (block
             (i32.store8 align=1
@@ -11649,11 +11661,13 @@
               )
               (loop $while-out$0 $while-in$1
                 (block
-                  (break $while-in$1
+                  (if
                     (i32.lt_s
                       (get_local $i1)
                       (get_local $i5)
                     )
+                    (break $while-in$1
+                    )
                   )
                   (block
                     (i32.store8 align=1
@@ -11673,11 +11687,13 @@
           )
           (loop $while-out$2 $while-in$3
             (block
-              (break $while-in$3
+              (if
                 (i32.lt_s
                   (get_local $i1)
                   (get_local $i7)
                 )
+                (break $while-in$3
+                )
               )
               (block
                 (i32.store align=4
@@ -11697,11 +11713,13 @@
       )
       (loop $while-out$4 $while-in$5
         (block
-          (break $while-in$5
+          (if
             (i32.lt_s
               (get_local $i1)
               (get_local $i4)
             )
+            (break $while-in$5
+            )
           )
           (block
             (i32.store8 align=1
diff --git a/test/emcc_hello_world.wast b/test/emcc_hello_world.wast
index 21394f768..7941533c6 100644
--- a/test/emcc_hello_world.wast
+++ b/test/emcc_hello_world.wast
@@ -2300,11 +2300,13 @@
               (i32.const 4)
             )
           )
-          (break $do-in$1
+          (if
             (i32.lt_s
               (get_local $dest)
               (get_local $stop)
             )
+            (break $do-in$1
+            )
           )
         )
       )
@@ -24869,11 +24871,13 @@
               )
               (loop $while-out$0 $while-in$1
                 (block
-                  (break $while-in$1
+                  (if
                     (i32.lt_s
                       (get_local $ptr)
                       (get_local $unaligned)
                     )
+                    (break $while-in$1
+                    )
                   )
                   (block
                     (i32.store8 align=1
@@ -24893,11 +24897,13 @@
           )
           (loop $while-out$2 $while-in$3
             (block
-              (break $while-in$3
+              (if
                 (i32.lt_s
                   (get_local $ptr)
                   (get_local $stop4)
                 )
+                (break $while-in$3
+                )
               )
               (block
                 (i32.store align=4
@@ -24917,11 +24923,13 @@
       )
       (loop $while-out$4 $while-in$5
         (block
-          (break $while-in$5
+          (if
             (i32.lt_s
               (get_local $ptr)
               (get_local $stop)
             )
+            (break $while-in$5
+            )
           )
           (block
             (i32.store8 align=1
@@ -25100,11 +25108,13 @@
         (block
           (loop $while-out$0 $while-in$1
             (block
-              (break $while-in$1
+              (if
                 (i32.and
                   (get_local $dest)
                   (i32.const 3)
                 )
+                (break $while-in$1
+                )
               )
               (block
                 (if
@@ -25145,11 +25155,13 @@
           )
           (loop $while-out$2 $while-in$3
             (block
-              (break $while-in$3
+              (if
                 (i32.ge_s
                   (get_local $num)
                   (i32.const 4)
                 )
+                (break $while-in$3
+                )
               )
               (block
                 (i32.store align=4
@@ -25183,11 +25195,13 @@
       )
       (loop $while-out$4 $while-in$5
         (block
-          (break $while-in$5
+          (if
             (i32.gt_s
               (get_local $num)
               (i32.const 0)
             )
+            (break $while-in$5
+            )
           )
           (block
             (i32.store8 align=1