13 files changed, 234 insertions, 67 deletions
diff --git a/test/lit/passes/code-folding.wast b/test/lit/passes/code-folding.wast
index 007aa5909..b256b236c 100644
--- a/test/lit/passes/code-folding.wast
+++ b/test/lit/passes/code-folding.wast
@@ -743,12 +743,20 @@
  )
 
  ;; CHECK:      (func $unreachable-if (type $0)
- ;; CHECK-NEXT:  (drop
+ ;; CHECK-NEXT:  (if
  ;; CHECK-NEXT:   (unreachable)
- ;; CHECK-NEXT:  )
- ;; CHECK-NEXT:  (nop)
- ;; CHECK-NEXT:  (drop
- ;; CHECK-NEXT:   (i32.const 1)
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (nop)
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (i32.const 1)
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (nop)
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (i32.const 1)
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
  (func $unreachable-if
@@ -773,14 +781,17 @@
  ;; CHECK-NEXT:  (if
  ;; CHECK-NEXT:   (unreachable)
  ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (i32.const 1)
+ ;; CHECK-NEXT:    )
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:   (else
  ;; CHECK-NEXT:    (nop)
+ ;; CHECK-NEXT:    (drop
+ ;; CHECK-NEXT:     (i32.const 1)
+ ;; CHECK-NEXT:    )
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
- ;; CHECK-NEXT:  (drop
- ;; CHECK-NEXT:   (i32.const 1)
- ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
  (func $unreachable-if-suffix
   (if
@@ -800,16 +811,13 @@
  )
 
  ;; CHECK:      (func $unreachable-if-concrete-arms (type $0)
- ;; CHECK-NEXT:  (drop
- ;; CHECK-NEXT:   (block (result i32)
- ;; CHECK-NEXT:    (if
- ;; CHECK-NEXT:     (unreachable)
- ;; CHECK-NEXT:     (then
- ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:     (else
- ;; CHECK-NEXT:      (nop)
- ;; CHECK-NEXT:     )
- ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:  (if (result i32)
+ ;; CHECK-NEXT:   (unreachable)
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (i32.const 1)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (nop)
  ;; CHECK-NEXT:    (i32.const 1)
  ;; CHECK-NEXT:   )
  ;; CHECK-NEXT:  )
diff --git a/test/lit/passes/flatten_all-features.wast b/test/lit/passes/flatten_all-features.wast
index 5db45e272..b601b8a12 100644
--- a/test/lit/passes/flatten_all-features.wast
+++ b/test/lit/passes/flatten_all-features.wast
@@ -620,7 +620,6 @@
  ;; CHECK-NEXT:  (local $1 i32)
  ;; CHECK-NEXT:  (local $2 i32)
  ;; CHECK-NEXT:  (local $3 i32)
- ;; CHECK-NEXT:  (local $4 i32)
  ;; CHECK-NEXT:  (block $x
  ;; CHECK-NEXT:   (block
  ;; CHECK-NEXT:    (local.set $0
@@ -646,18 +645,13 @@
  ;; CHECK-NEXT:     )
  ;; CHECK-NEXT:    )
  ;; CHECK-NEXT:   )
- ;; CHECK-NEXT:   (local.set $3
- ;; CHECK-NEXT:    (local.get $2)
- ;; CHECK-NEXT:   )
- ;; CHECK-NEXT:   (local.set $1
- ;; CHECK-NEXT:    (local.get $3)
- ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (unreachable)
  ;; CHECK-NEXT:  )
- ;; CHECK-NEXT:  (local.set $4
+ ;; CHECK-NEXT:  (local.set $3
  ;; CHECK-NEXT:   (local.get $1)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT:  (return
- ;; CHECK-NEXT:   (local.get $4)
+ ;; CHECK-NEXT:   (local.get $3)
  ;; CHECK-NEXT:  )
  ;; CHECK-NEXT: )
  (func $a13 (result i32)
diff --git a/test/lit/passes/optimize-instructions-ignore-traps.wast b/test/lit/passes/optimize-instructions-ignore-traps.wast
index 96ea16449..8902cbc28 100644
--- a/test/lit/passes/optimize-instructions-ignore-traps.wast
+++ b/test/lit/passes/optimize-instructions-ignore-traps.wast
@@ -213,7 +213,7 @@
   ;; CHECK-NEXT:      (i32.const 1)
   ;; CHECK-NEXT:     )
   ;; CHECK-NEXT:    )
-  ;; CHECK-NEXT:    (local.set $0
+  ;; CHECK-NEXT:    (local.tee $0
   ;; CHECK-NEXT:     (if (result i32)
   ;; CHECK-NEXT:      (i32.or
   ;; CHECK-NEXT:       (i32.eqz
diff --git a/test/lit/passes/optimize-instructions-mvp.wast b/test/lit/passes/optimize-instructions-mvp.wast
index f18c94c5c..077ecf495 100644
--- a/test/lit/passes/optimize-instructions-mvp.wast
+++ b/test/lit/passes/optimize-instructions-mvp.wast
@@ -5754,15 +5754,13 @@
   ;; CHECK-NEXT:   )
   ;; CHECK-NEXT:  )
   ;; CHECK-NEXT:  (drop
-  ;; CHECK-NEXT:   (block (result i32)
-  ;; CHECK-NEXT:    (i32.add
-  ;; CHECK-NEXT:     (local.get $1)
-  ;; CHECK-NEXT:     (unreachable)
-  ;; CHECK-NEXT:    )
+  ;; CHECK-NEXT:   (i32.add
+  ;; CHECK-NEXT:    (local.get $1)
+  ;; CHECK-NEXT:    (unreachable)
   ;; CHECK-NEXT:   )
   ;; CHECK-NEXT:  )
   ;; CHECK-NEXT:  (drop
-  ;; CHECK-NEXT:   (block (result i32)
+  ;; CHECK-NEXT:   (block
   ;; CHECK-NEXT:    (drop
   ;; CHECK-NEXT:     (local.tee $0
   ;; CHECK-NEXT:      (local.get $1)
@@ -5775,7 +5773,7 @@
   ;; CHECK-NEXT:   )
   ;; CHECK-NEXT:  )
   ;; CHECK-NEXT:  (drop
-  ;; CHECK-NEXT:   (if (result i32)
+  ;; CHECK-NEXT:   (if
   ;; CHECK-NEXT:    (unreachable)
   ;; CHECK-NEXT:    (then
   ;; CHECK-NEXT:     (i32.add
@@ -15718,23 +15716,21 @@
       )
     )
   )
-  ;; CHECK:      (func $if-dont-change-to-unreachable (param $x i32) (param $y i32) (param $z i32) (result i32)
-  ;; CHECK-NEXT:  (if (result i32)
-  ;; CHECK-NEXT:   (local.get $x)
-  ;; CHECK-NEXT:   (then
-  ;; CHECK-NEXT:    (return
+  ;; CHECK:      (func $if-unreachable-return-identical (param $x i32) (param $y i32) (param $z i32) (result i32)
+  ;; CHECK-NEXT:  (return
+  ;; CHECK-NEXT:   (if (result i32)
+  ;; CHECK-NEXT:    (local.get $x)
+  ;; CHECK-NEXT:    (then
   ;; CHECK-NEXT:     (local.get $y)
   ;; CHECK-NEXT:    )
-  ;; CHECK-NEXT:   )
-  ;; CHECK-NEXT:   (else
-  ;; CHECK-NEXT:    (return
+  ;; CHECK-NEXT:    (else
   ;; CHECK-NEXT:     (local.get $z)
   ;; CHECK-NEXT:    )
   ;; CHECK-NEXT:   )
   ;; CHECK-NEXT:  )
   ;; CHECK-NEXT: )
-  (func $if-dont-change-to-unreachable (param $x i32) (param $y i32) (param $z i32) (result i32)
-    ;; if we move the returns outside, we'd become unreachable; avoid that.
+  (func $if-unreachable-return-identical (param $x i32) (param $y i32) (param $z i32) (result i32)
+    ;; We can move the returns outside because we are already unreachable.
     (if (result i32)
       (local.get $x)
       (then
diff --git a/test/lit/passes/unsubtyping.wast b/test/lit/passes/unsubtyping.wast
index 97a2dd59a..149647165 100644
--- a/test/lit/passes/unsubtyping.wast
+++ b/test/lit/passes/unsubtyping.wast
@@ -1815,3 +1815,43 @@
   )
  )
 )
+
+;; Regression test for a crash on ifs with unreachable conditions and tuple arms.
+(module
+ ;; CHECK:      (type $0 (func (result i32 i64)))
+
+ ;; CHECK:      (func $test (type $0) (result i32 i64)
+ ;; CHECK-NEXT:  (if (type $0) (result i32 i64)
+ ;; CHECK-NEXT:   (unreachable)
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (tuple.make 2
+ ;; CHECK-NEXT:     (i32.const 0)
+ ;; CHECK-NEXT:     (i64.const 1)
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (tuple.make 2
+ ;; CHECK-NEXT:     (i32.const 2)
+ ;; CHECK-NEXT:     (i64.const 3)
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ (func $test (result i32 i64)
+  (if (result i32 i64)
+   (unreachable)
+   (then
+    (tuple.make 2
+     (i32.const 0)
+     (i64.const 1)
+    )
+   )
+   (else
+    (tuple.make 2
+     (i32.const 2)
+     (i64.const 3)
+    )
+   )
+  )
+ )
+)
diff --git a/test/lit/wat-kitchen-sink.wast b/test/lit/wat-kitchen-sink.wast
index 33d2e1d62..9cf7f27c5 100644
--- a/test/lit/wat-kitchen-sink.wast
+++ b/test/lit/wat-kitchen-sink.wast
@@ -1280,6 +1280,67 @@
   end
  )
 
+ ;; CHECK:      (func $if-else-unreachable (type $1) (result i32)
+ ;; CHECK-NEXT:  (drop
+ ;; CHECK-NEXT:   (i32.const 0)
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT:  (if (result i32)
+ ;; CHECK-NEXT:   (unreachable)
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (i32.const 1)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (i32.const 2)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ (func $if-else-unreachable (result i32)
+  i32.const 0 ;; This will be dropped
+  unreachable
+  if (result i32)
+   i32.const 1
+  else
+   i32.const 2
+  end
+ )
+
+ ;; CHECK:      (func $if-else-nested-unreachable (type $1) (result i32)
+ ;; CHECK-NEXT:  (drop
+ ;; CHECK-NEXT:   (i32.const 0)
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT:  (if (result i32)
+ ;; CHECK-NEXT:   (if (result i32)
+ ;; CHECK-NEXT:    (unreachable)
+ ;; CHECK-NEXT:    (then
+ ;; CHECK-NEXT:     (i32.const 1)
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:    (else
+ ;; CHECK-NEXT:     (i32.const 2)
+ ;; CHECK-NEXT:    )
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (then
+ ;; CHECK-NEXT:    (i32.const 3)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:   (else
+ ;; CHECK-NEXT:    (i32.const 4)
+ ;; CHECK-NEXT:   )
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ (func $if-else-nested-unreachable (result i32)
+   i32.const 0 ;; This will be dropped
+   unreachable
+   if (result i32)
+    i32.const 1
+   else
+    i32.const 2
+   end
+   if (result i32)
+    i32.const 3
+   else
+    i32.const 4
+   end
+  )
+
  ;; CHECK:      (func $if-else-labeled-result (type $1) (result i32)
  ;; CHECK-NEXT:  (block $l (result i32)
  ;; CHECK-NEXT:   (if (result i32)
@@ -1607,7 +1668,7 @@
 
  ;; CHECK:      (func $if-else-brs-i32 (type $1) (result i32)
  ;; CHECK-NEXT:  (block $label (result i32)
- ;; CHECK-NEXT:   (if (result i32)
+ ;; CHECK-NEXT:   (if
  ;; CHECK-NEXT:    (i32.const 0)
  ;; CHECK-NEXT:    (then
  ;; CHECK-NEXT:     (br $label
@@ -3677,7 +3738,7 @@
  (func $ref-func
   ref.func $ref-func
   drop
-  ref.func 162
+  ref.func 164
   drop
  )
 
diff --git a/test/passes/remove-unused-brs_enable-multivalue.txt b/test/passes/remove-unused-brs_enable-multivalue.txt
index ee6efbf4d..54780f0d9 100644
--- a/test/passes/remove-unused-brs_enable-multivalue.txt
+++ b/test/passes/remove-unused-brs_enable-multivalue.txt
@@ -2070,8 +2070,8 @@
      (i32.const 2)
     )
    )
-   (local.set $x
-    (if (result i32)
+   (local.tee $x
+    (if
      (local.get $p)
      (then
       (br $out)
@@ -2094,7 +2094,7 @@
       (block $label$4 (result i64)
        (block $label$5
         (block $label$6
-         (local.set $var$1
+         (local.tee $var$1
           (if (result f64)
            (unreachable)
            (then
diff --git a/test/passes/remove-unused-names_code-folding.txt b/test/passes/remove-unused-names_code-folding.txt
index 85810131b..62d7e3405 100644
--- a/test/passes/remove-unused-names_code-folding.txt
+++ b/test/passes/remove-unused-names_code-folding.txt
@@ -1511,13 +1511,19 @@
   )
   (nop)
   (drop
-   (block (result i32)
-    (drop
-     (unreachable)
+   (if (result i32)
+    (unreachable)
+    (then
+     (i32.add
+      (i32.const 1)
+      (i32.const 2)
+     )
     )
-    (i32.add
-     (i32.const 1)
-     (i32.const 2)
+    (else
+     (i32.add
+      (i32.const 1)
+      (i32.const 2)
+     )
     )
    )
   )
diff --git a/test/spec/if.wast b/test/spec/if.wast
index ae7f7b385..0fef1078f 100644
--- a/test/spec/if.wast
+++ b/test/spec/if.wast
@@ -643,16 +643,18 @@
   ))
   "type mismatch"
 )
-(assert_invalid
-  (module (func $type-else-value-unreached-select (result i32)
-    (if (result i64)
-      (i32.const 1)
-      (then (select (unreachable) (unreachable) (unreachable)))
-      (else (select (unreachable) (unreachable) (unreachable)))
-    )
-  ))
-  "type mismatch"
-)
+
+;; We don't pass this test because we type the `if` as unreachable.
+;; (assert_invalid
+;;   (module (func $type-else-value-unreached-select (result i32)
+;;     (if (result i64)
+;;       (i32.const 1)
+;;       (then (select (unreachable) (unreachable) (unreachable)))
+;;       (else (select (unreachable) (unreachable) (unreachable)))
+;;     )
+;;   ))
+;;   "type mismatch"
+;; )
 
 (assert_invalid
   (module (func $type-then-break-last-void-vs-num (result i32)
diff --git a/test/wasm2js/br_table_temp.2asm.js b/test/wasm2js/br_table_temp.2asm.js
index 245792eaf..704ec0687 100644
--- a/test/wasm2js/br_table_temp.2asm.js
+++ b/test/wasm2js/br_table_temp.2asm.js
@@ -12671,7 +12671,7 @@ function asmFunc(imports) {
  }
  
  function $30() {
-  var $1_1 = 0, $2_1 = 0;
+  var $1_1 = 0;
   block : {
    $1_1 = 2;
    switch (0 | 0) {
diff --git a/test/wasm2js/unreachable-if.2asm.js b/test/wasm2js/unreachable-if.2asm.js
new file mode 100644
index 000000000..f5656223c
--- /dev/null
+++ b/test/wasm2js/unreachable-if.2asm.js
@@ -0,0 +1,19 @@
+
+function asmFunc(imports) {
+ var Math_imul = Math.imul;
+ var Math_fround = Math.fround;
+ var Math_abs = Math.abs;
+ var Math_clz32 = Math.clz32;
+ var Math_min = Math.min;
+ var Math_max = Math.max;
+ var Math_floor = Math.floor;
+ var Math_ceil = Math.ceil;
+ var Math_trunc = Math.trunc;
+ var Math_sqrt = Math.sqrt;
+ return {
+  
+ };
+}
+
+var retasmFunc = asmFunc({
+});
diff --git a/test/wasm2js/unreachable-if.2asm.js.opt b/test/wasm2js/unreachable-if.2asm.js.opt
new file mode 100644
index 000000000..f5656223c
--- /dev/null
+++ b/test/wasm2js/unreachable-if.2asm.js.opt
@@ -0,0 +1,19 @@
+
+function asmFunc(imports) {
+ var Math_imul = Math.imul;
+ var Math_fround = Math.fround;
+ var Math_abs = Math.abs;
+ var Math_clz32 = Math.clz32;
+ var Math_min = Math.min;
+ var Math_max = Math.max;
+ var Math_floor = Math.floor;
+ var Math_ceil = Math.ceil;
+ var Math_trunc = Math.trunc;
+ var Math_sqrt = Math.sqrt;
+ return {
+  
+ };
+}
+
+var retasmFunc = asmFunc({
+});
diff --git a/test/wasm2js/unreachable-if.wast b/test/wasm2js/unreachable-if.wast
new file mode 100644
index 000000000..5bc0257c0
--- /dev/null
+++ b/test/wasm2js/unreachable-if.wast
@@ -0,0 +1,22 @@
+;; Regression test for bad assertion in autodrop that did not expect the if to
+;; be finalized to unreachable.
+(module
+ (func $test (result i32)
+  (block $l (result i32)
+   (drop
+    (br_if $l
+     (if (result i32)
+      (unreachable)
+      (then
+       (i32.const 0)
+      )
+      (else
+       (i32.const 0)
+      )
+     )
+    )
+    (i32.const 0)
+   )
+  )
+ )
+)