Optimize select with const arms (#2869)

  x ? 1 : 0   =>   !!x

and so forth.

4 files changed, 400 insertions, 56 deletions

diff --git a/test/passes/optimize-instructions_all-features.txt b/test/passes/optimize-instructions_all-features.txt
index 76c6ffe0a..e08702b91 100644
--- a/test/passes/optimize-instructions_all-features.txt
+++ b/test/passes/optimize-instructions_all-features.txt
@@ -3,8 +3,8 @@
  (type $i32_=>_i32 (func (param i32) (result i32)))
  (type $none_=>_i32 (func (result i32)))
  (type $none_=>_none (func))
- (type $i32_=>_none (func (param i32)))
  (type $i32_i64_=>_none (func (param i32 i64)))
+ (type $i32_=>_none (func (param i32)))
  (type $i32_i32_=>_i32 (func (param i32 i32) (result i32)))
  (type $none_=>_i64 (func (result i64)))
  (type $i64_=>_i64 (func (param i64) (result i64)))
@@ -3228,7 +3228,7 @@
    (local.get $x)
   )
  )
- (func $select-on-const (param $x i32) (param $y i32)
+ (func $select-on-const (param $x i32) (param $y i64)
   (drop
    (local.get $x)
   )
@@ -3264,6 +3264,157 @@
     (i32.const 6)
    )
   )
+  (drop
+   (i32.eqz
+    (i32.eqz
+     (local.get $x)
+    )
+   )
+  )
+  (drop
+   (i32.eqz
+    (local.get $x)
+   )
+  )
+  (drop
+   (i32.ge_s
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.lt_s
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.lt_s
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.gt_s
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.le_s
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i32.ge_s
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i32.eqz
+     (i32.eqz
+      (local.get $x)
+     )
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i32.eqz
+     (local.get $x)
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i64.eqz
+     (local.get $y)
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i32.eqz
+     (i64.eqz
+      (local.get $y)
+     )
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i64.ge_s
+     (local.get $y)
+     (i64.const 0)
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i64.lt_s
+     (local.get $y)
+     (i64.const 0)
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i64.lt_s
+     (local.get $y)
+     (i64.const 0)
+    )
+   )
+  )
+  (drop
+   (i64.extend_i32_u
+    (i64.ge_s
+     (local.get $y)
+     (i64.const 0)
+    )
+   )
+  )
+  (drop
+   (select
+    (i32.const 0)
+    (local.get $x)
+    (i32.const 0)
+   )
+  )
+  (drop
+   (select
+    (i32.const 2)
+    (local.get $x)
+    (i32.const 2)
+   )
+  )
+  (drop
+   (select
+    (local.get $x)
+    (i32.const 2)
+    (local.get $x)
+   )
+  )
+  (drop
+   (select
+    (local.get $y)
+    (i64.const 0)
+    (i64.eqz
+     (i64.const 0)
+    )
+   )
+  )
+  (drop
+   (select
+    (local.get $y)
+    (i64.const 2)
+    (i64.eqz
+     (i64.const 2)
+    )
+   )
+  )
  )
  (func $optimize-boolean (param $x i32)
   (drop
@@ -3563,6 +3714,19 @@
  (func $if-arms-subtype (result externref)
   (ref.null)
  )
+ (func $optimize-boolean-context (param $x i32) (param $y i32)
+  (if
+   (local.get $x)
+   (unreachable)
+  )
+  (drop
+   (select
+    (local.get $x)
+    (local.get $y)
+    (local.get $x)
+   )
+  )
+ )
 )
 (module
  (type $none_=>_none (func))
diff --git a/test/passes/optimize-instructions_all-features.wast b/test/passes/optimize-instructions_all-features.wast
index c62f0bc42..2790cc9ea 100644
--- a/test/passes/optimize-instructions_all-features.wast
+++ b/test/passes/optimize-instructions_all-features.wast
@@ -3714,7 +3714,7 @@
       )
     )
   )
-  (func $select-on-const (param $x i32) (param $y i32)
+  (func $select-on-const (param $x i32) (param $y i64)
     (drop
       (select
         (i32.const 2)
@@ -3765,6 +3765,200 @@
         (i32.const 1)
       )
     )
+    (drop
+      (select
+        (i32.const 1)
+        (i32.const 0)
+        (local.get $x)
+      )
+    )
+    (drop
+      (select
+        (i32.const 0)
+        (i32.const 1)
+        (local.get $x)
+      )
+    )
+    (drop
+      (select
+        (i32.const 0)
+        (i32.const 1)
+        (i32.lt_s
+          (local.get $x)
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i32.const 1)
+        (i32.const 0)
+        (i32.lt_s
+          (local.get $x)
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i32.const 0)
+        (i32.const 1)
+        (i32.ge_s
+          (local.get $x)
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i32.const 1)
+        (i32.const 0)
+        (i32.gt_s
+          (local.get $x)
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i32.const 0)
+        (i32.const 1)
+        (i32.gt_s
+          (local.get $x)
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i32.const 1)
+        (i32.const 0)
+        (i32.ge_s
+          (local.get $x)
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i64.const 1)
+        (i64.const 0)
+        (local.get $x)
+      )
+    )
+    (drop
+      (select
+        (i64.const 0)
+        (i64.const 1)
+        (local.get $x)
+      )
+    )
+    (drop
+      (select
+        (i64.const 1)
+        (i64.const 0)
+        (i64.eqz
+          (local.get $y)
+        )
+      )
+    )
+    (drop
+      (select
+        (i64.const 0)
+        (i64.const 1)
+        (i64.eqz
+          (local.get $y)
+        )
+      )
+    )
+    (drop
+      (select
+        (i64.const 0)
+        (i64.const 1)
+        (i64.lt_s
+          (local.get $y)
+          (i64.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i64.const 1)
+        (i64.const 0)
+        (i64.lt_s
+          (local.get $y)
+          (i64.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i64.const 0)
+        (i64.const 1)
+        (i64.ge_s
+          (local.get $y)
+          (i64.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (i64.const 1)
+        (i64.const 0)
+        (i64.ge_s
+          (local.get $y)
+          (i64.const 0)
+        )
+      )
+    )
+    ;; optimize boolean
+    (drop
+      (select
+        (local.get $x)
+        (i32.const 0)
+        (i32.eqz
+          (i32.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (local.get $x)
+        (i32.const 2)
+        (i32.eqz
+          (i32.const 2)
+        )
+      )
+    )
+    (drop
+      (select
+        (local.get $x)
+        (i32.const 2)
+        (i32.eqz
+          (i32.eqz
+            (local.get $x)
+          )
+        )
+      )
+    )
+    (drop
+      (select
+        (local.get $y)
+        (i64.const 0)
+        (i64.eqz
+          (i64.const 0)
+        )
+      )
+    )
+    (drop
+      (select
+        (local.get $y)
+        (i64.const 2)
+        (i64.eqz
+          (i64.const 2)
+        )
+      )
+    )
   )
   (func $optimize-boolean (param $x i32)
     (drop
@@ -4021,6 +4215,24 @@
       (ref.null)
     )
   )
+  (func $optimize-boolean-context (param $x i32) (param $y i32)
+    ;; 0 - x   ==>   x
+    (if
+      (i32.sub
+        (i32.const 0)
+        (local.get $x)
+      )
+      (unreachable)
+    )
+    (drop (select
+      (local.get $x)
+      (local.get $y)
+      (i32.sub
+        (i32.const 0)
+        (local.get $x)
+      )
+    ))
+  )
 )
 (module
   (import "env" "memory" (memory $0 (shared 256 256)))
diff --git a/test/wasm2js/i64-lowering.2asm.js.opt b/test/wasm2js/i64-lowering.2asm.js.opt
index e5d955dfd..f4d940863 100644
--- a/test/wasm2js/i64-lowering.2asm.js.opt
+++ b/test/wasm2js/i64-lowering.2asm.js.opt
@@ -20,76 +20,44 @@ function asmFunc(global, env, buffer) {
  var abort = env.abort;
  var nan = global.NaN;
  var infinity = global.Infinity;
- function $3($0, $1, $2, $3_1) {
-  $0 = $0 | 0;
-  $1 = $1 | 0;
-  $2 = $2 | 0;
-  $3_1 = $3_1 | 0;
-  return (($1 | 0) > ($3_1 | 0) ? 1 : ($1 | 0) >= ($3_1 | 0) ? ($0 >>> 0 < $2 >>> 0 ? 0 : 1) : 0) | 0;
+ function legalstub$1($0, $1, $2, $3) {
+  return ($0 | 0) == ($2 | 0) & ($1 | 0) == ($3 | 0);
  }
  
- function $4($0, $1, $2, $3_1) {
-  $0 = $0 | 0;
-  $1 = $1 | 0;
-  $2 = $2 | 0;
-  $3_1 = $3_1 | 0;
-  return (($1 | 0) > ($3_1 | 0) ? 1 : ($1 | 0) >= ($3_1 | 0) ? ($0 >>> 0 <= $2 >>> 0 ? 0 : 1) : 0) | 0;
+ function legalstub$2($0, $1, $2, $3) {
+  return ($0 | 0) != ($2 | 0) | ($1 | 0) != ($3 | 0);
  }
  
- function $5($0, $1, $2, $3_1) {
-  $0 = $0 | 0;
-  $1 = $1 | 0;
-  $2 = $2 | 0;
-  $3_1 = $3_1 | 0;
-  return (($1 | 0) < ($3_1 | 0) ? 1 : ($1 | 0) <= ($3_1 | 0) ? ($0 >>> 0 > $2 >>> 0 ? 0 : 1) : 0) | 0;
+ function legalstub$3($0, $1, $2, $3) {
+  return ($1 | 0) > ($3 | 0) ? 1 : ($1 | 0) >= ($3 | 0) ? $0 >>> 0 >= $2 >>> 0 : 0;
  }
  
- function $6($0, $1, $2, $3_1) {
-  $0 = $0 | 0;
-  $1 = $1 | 0;
-  $2 = $2 | 0;
-  $3_1 = $3_1 | 0;
-  return (($1 | 0) < ($3_1 | 0) ? 1 : ($1 | 0) <= ($3_1 | 0) ? ($0 >>> 0 >= $2 >>> 0 ? 0 : 1) : 0) | 0;
+ function legalstub$4($0, $1, $2, $3) {
+  return ($1 | 0) > ($3 | 0) ? 1 : ($1 | 0) >= ($3 | 0) ? $0 >>> 0 > $2 >>> 0 : 0;
  }
  
- function legalstub$1($0, $1, $2, $3_1) {
-  return ($0 | 0) == ($2 | 0) & ($1 | 0) == ($3_1 | 0);
+ function legalstub$5($0, $1, $2, $3) {
+  return ($1 | 0) < ($3 | 0) ? 1 : ($1 | 0) <= ($3 | 0) ? $0 >>> 0 <= $2 >>> 0 : 0;
  }
  
- function legalstub$2($0, $1, $2, $3_1) {
-  return ($0 | 0) != ($2 | 0) | ($1 | 0) != ($3_1 | 0);
+ function legalstub$6($0, $1, $2, $3) {
+  return ($1 | 0) < ($3 | 0) ? 1 : ($1 | 0) <= ($3 | 0) ? $0 >>> 0 < $2 >>> 0 : 0;
  }
  
- function legalstub$3($0, $1, $2, $3_1) {
-  return $3($0, $1, $2, $3_1);
+ function legalstub$7($0, $1, $2, $3) {
+  return ($1 | 0) == ($3 | 0) & $0 >>> 0 >= $2 >>> 0 | $1 >>> 0 > $3 >>> 0;
  }
  
- function legalstub$4($0, $1, $2, $3_1) {
-  return $4($0, $1, $2, $3_1);
+ function legalstub$8($0, $1, $2, $3) {
+  return ($1 | 0) == ($3 | 0) & $0 >>> 0 > $2 >>> 0 | $1 >>> 0 > $3 >>> 0;
  }
  
- function legalstub$5($0, $1, $2, $3_1) {
-  return $5($0, $1, $2, $3_1);
+ function legalstub$9($0, $1, $2, $3) {
+  return ($1 | 0) == ($3 | 0) & $0 >>> 0 <= $2 >>> 0 | $1 >>> 0 < $3 >>> 0;
  }
  
- function legalstub$6($0, $1, $2, $3_1) {
-  return $6($0, $1, $2, $3_1);
- }
- 
- function legalstub$7($0, $1, $2, $3_1) {
-  return ($1 | 0) == ($3_1 | 0) & $0 >>> 0 >= $2 >>> 0 | $1 >>> 0 > $3_1 >>> 0;
- }
- 
- function legalstub$8($0, $1, $2, $3_1) {
-  return ($1 | 0) == ($3_1 | 0) & $0 >>> 0 > $2 >>> 0 | $1 >>> 0 > $3_1 >>> 0;
- }
- 
- function legalstub$9($0, $1, $2, $3_1) {
-  return ($1 | 0) == ($3_1 | 0) & $0 >>> 0 <= $2 >>> 0 | $1 >>> 0 < $3_1 >>> 0;
- }
- 
- function legalstub$10($0, $1, $2, $3_1) {
-  return ($1 | 0) == ($3_1 | 0) & $0 >>> 0 < $2 >>> 0 | $1 >>> 0 < $3_1 >>> 0;
+ function legalstub$10($0, $1, $2, $3) {
+  return ($1 | 0) == ($3 | 0) & $0 >>> 0 < $2 >>> 0 | $1 >>> 0 < $3 >>> 0;
  }
  
  var FUNCTION_TABLE = [];
diff --git a/test/wasm2js/nested-selects.2asm.js.opt b/test/wasm2js/nested-selects.2asm.js.opt
index 16d5529cd..9bb06d563 100644
--- a/test/wasm2js/nested-selects.2asm.js.opt
+++ b/test/wasm2js/nested-selects.2asm.js.opt
@@ -22,7 +22,7 @@ function asmFunc(global, env, buffer) {
  var infinity = global.Infinity;
  function $1($0) {
   $0 = $0 | 0;
-  return (($0 | 0) < 0 ? -1 : ($0 | 0) > 0 ? 1 : 0) | 0;
+  return (($0 | 0) < 0 ? -1 : ($0 | 0) > 0) | 0;
  }
  
  var FUNCTION_TABLE = [];