Canonicalize subtraction with constant on the right to addition (#3321)

Using addition in more places is better for gzip, and helps simplify the
optimizer as well.

Add a FinalOptimizer phase to do optimizations like our signed LEB tweaks, to
reduce binary size in the rare case when we do want a subtraction.

14 files changed, 20 insertions, 20 deletions

diff --git a/test/wasm2js/atomics_32.2asm.js b/test/wasm2js/atomics_32.2asm.js
index 12cdbe8ff..d3c1ba22b 100644
--- a/test/wasm2js/atomics_32.2asm.js
+++ b/test/wasm2js/atomics_32.2asm.js
@@ -147,7 +147,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   memorySegments[0] = base64DecodeToExistingUint8Array(new Uint8Array(6), 0, "aGVsbG8s");
 memorySegments[1] = base64DecodeToExistingUint8Array(new Uint8Array(6), 0, "d29ybGQh");
diff --git a/test/wasm2js/atomics_32.2asm.js.opt b/test/wasm2js/atomics_32.2asm.js.opt
index 4a7a5d85f..a12b684dc 100644
--- a/test/wasm2js/atomics_32.2asm.js.opt
+++ b/test/wasm2js/atomics_32.2asm.js.opt
@@ -143,7 +143,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   memorySegments[0] = base64DecodeToExistingUint8Array(new Uint8Array(6), 0, "aGVsbG8s");
 memorySegments[1] = base64DecodeToExistingUint8Array(new Uint8Array(6), 0, "d29ybGQh");
diff --git a/test/wasm2js/bulk-memory.2asm.js b/test/wasm2js/bulk-memory.2asm.js
index 2b7431486..c847dbdfd 100644
--- a/test/wasm2js/bulk-memory.2asm.js
+++ b/test/wasm2js/bulk-memory.2asm.js
@@ -180,7 +180,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 0, "qrvM3Q==");
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); }
@@ -287,7 +287,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   memorySegments[0] = base64DecodeToExistingUint8Array(new Uint8Array(4), 0, "qrvM3Q==");
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); }
@@ -405,7 +405,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   memorySegments[0] = base64DecodeToExistingUint8Array(new Uint8Array(0), 0, "");
 base64DecodeToExistingUint8Array(bufferView, 0, "");
diff --git a/test/wasm2js/bulk-memory.2asm.js.opt b/test/wasm2js/bulk-memory.2asm.js.opt
index 77e682c41..4e6ccc529 100644
--- a/test/wasm2js/bulk-memory.2asm.js.opt
+++ b/test/wasm2js/bulk-memory.2asm.js.opt
@@ -180,7 +180,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 0, "qrvM3Q==");
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); }
@@ -287,7 +287,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   memorySegments[0] = base64DecodeToExistingUint8Array(new Uint8Array(4), 0, "qrvM3Q==");
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); }
diff --git a/test/wasm2js/dynamicLibrary.2asm.js b/test/wasm2js/dynamicLibrary.2asm.js
index b570fab36..22d483f45 100644
--- a/test/wasm2js/dynamicLibrary.2asm.js
+++ b/test/wasm2js/dynamicLibrary.2asm.js
@@ -81,7 +81,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, memoryBase, "ZHluYW1pYyBkYXRh");
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); },
diff --git a/test/wasm2js/dynamicLibrary.2asm.js.opt b/test/wasm2js/dynamicLibrary.2asm.js.opt
index 4d7b4ac42..cd959acb8 100644
--- a/test/wasm2js/dynamicLibrary.2asm.js.opt
+++ b/test/wasm2js/dynamicLibrary.2asm.js.opt
@@ -73,7 +73,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, memoryBase, "ZHluYW1pYyBkYXRh");
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); },
diff --git a/test/wasm2js/emscripten-grow-no.2asm.js b/test/wasm2js/emscripten-grow-no.2asm.js
index 998527287..4d6bb4c77 100644
--- a/test/wasm2js/emscripten-grow-no.2asm.js
+++ b/test/wasm2js/emscripten-grow-no.2asm.js
@@ -63,7 +63,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 1600, "YWJj");
 return asmFunc(asmLibraryArg, wasmMemory.buffer)
diff --git a/test/wasm2js/emscripten-grow-no.2asm.js.opt b/test/wasm2js/emscripten-grow-no.2asm.js.opt
index 998527287..4d6bb4c77 100644
--- a/test/wasm2js/emscripten-grow-no.2asm.js.opt
+++ b/test/wasm2js/emscripten-grow-no.2asm.js.opt
@@ -63,7 +63,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 1600, "YWJj");
 return asmFunc(asmLibraryArg, wasmMemory.buffer)
diff --git a/test/wasm2js/emscripten-grow-yes.2asm.js b/test/wasm2js/emscripten-grow-yes.2asm.js
index 3cb5371b1..213524377 100644
--- a/test/wasm2js/emscripten-grow-yes.2asm.js
+++ b/test/wasm2js/emscripten-grow-yes.2asm.js
@@ -87,7 +87,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 1600, "YWJj");
 return asmFunc(asmLibraryArg, wasmMemory.buffer)
diff --git a/test/wasm2js/emscripten-grow-yes.2asm.js.opt b/test/wasm2js/emscripten-grow-yes.2asm.js.opt
index 3cb5371b1..213524377 100644
--- a/test/wasm2js/emscripten-grow-yes.2asm.js.opt
+++ b/test/wasm2js/emscripten-grow-yes.2asm.js.opt
@@ -87,7 +87,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 1600, "YWJj");
 return asmFunc(asmLibraryArg, wasmMemory.buffer)
diff --git a/test/wasm2js/emscripten.2asm.js b/test/wasm2js/emscripten.2asm.js
index 9d08b03a2..e71aaaa83 100644
--- a/test/wasm2js/emscripten.2asm.js
+++ b/test/wasm2js/emscripten.2asm.js
@@ -220,7 +220,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 1024, "aGVsbG8sIHdvcmxkIQoAAJwMAAAtKyAgIDBYMHgAKG51bGwpAAAAAAAAAAAAAAAAEQAKABEREQAAAAAFAAAAAAAACQAAAAALAAAAAAAAAAARAA8KERERAwoHAAETCQsLAAAJBgsAAAsABhEAAAAREREAAAAAAAAAAAAAAAAAAAAACwAAAAAAAAAAEQAKChEREQAKAAACAAkLAAAACQALAAALAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAwAAAAAAAAAAAAAAAwAAAAADAAAAAAJDAAAAAAADAAADAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAOAAAAAAAAAAAAAAANAAAABA0AAAAACQ4AAAAAAA4AAA4AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAEAAAAAAAAAAAAAAADwAAAAAPAAAAAAkQAAAAAAAQAAAQAAASAAAAEhISAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABIAAAASEhIAAAAAAAAJAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAALAAAAAAAAAAAAAAAKAAAAAAoAAAAACQsAAAAAAAsAAAsAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAADAAAAAAAAAAAAAAADAAAAAAMAAAAAAkMAAAAAAAMAAAMAAAwMTIzNDU2Nzg5QUJDREVGLTBYKzBYIDBYLTB4KzB4IDB4AGluZgBJTkYAbmFuAE5BTgAuAA==");
 base64DecodeToExistingUint8Array(bufferView, 1600, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=");
diff --git a/test/wasm2js/emscripten.2asm.js.opt b/test/wasm2js/emscripten.2asm.js.opt
index 0e438f81d..05ecfea7d 100644
--- a/test/wasm2js/emscripten.2asm.js.opt
+++ b/test/wasm2js/emscripten.2asm.js.opt
@@ -201,7 +201,7 @@ for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i
       if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
       if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
     }
-    return uint8Array; 
+    return uint8Array;
   }
   base64DecodeToExistingUint8Array(bufferView, 1024, "aGVsbG8sIHdvcmxkIQoAAJwMAAAtKyAgIDBYMHgAKG51bGwp");
 base64DecodeToExistingUint8Array(bufferView, 1072, "EQAKABEREQAAAAAFAAAAAAAACQAAAAALAAAAAAAAAAARAA8KERERAwoHAAETCQsLAAAJBgsAAAsABhEAAAARERE=");
diff --git a/test/wasm2js/i64-ctz.2asm.js.opt b/test/wasm2js/i64-ctz.2asm.js.opt
index aaacbfc51..9cda827f4 100644
--- a/test/wasm2js/i64-ctz.2asm.js.opt
+++ b/test/wasm2js/i64-ctz.2asm.js.opt
@@ -30,8 +30,8 @@ function asmFunc(env) {
  function __wasm_ctz_i64($0, $1) {
   var $2 = 0, $3 = 0;
   if ($0 | $1) {
-   $2 = $1 + -1 | 0;
-   $3 = $0 + -1 | 0;
+   $2 = $1 - 1 | 0;
+   $3 = $0 - 1 | 0;
    $2 = ($3 | 0) != -1 ? $2 + 1 | 0 : $2;
    $3 = Math_clz32($0 ^ $3) + 32 | 0;
    $0 = Math_clz32($1 ^ $2);
diff --git a/test/wasm2js/unary-ops.2asm.js.opt b/test/wasm2js/unary-ops.2asm.js.opt
index b854489b6..272ea822c 100644
--- a/test/wasm2js/unary-ops.2asm.js.opt
+++ b/test/wasm2js/unary-ops.2asm.js.opt
@@ -26,7 +26,7 @@ function asmFunc(env) {
  function $7($0) {
   $0 = $0 | 0;
   if ($0) {
-   $0 = 31 - Math_clz32($0 + -1 ^ $0) | 0
+   $0 = 31 - Math_clz32($0 - 1 ^ $0) | 0
   } else {
    $0 = 32
   }
@@ -71,8 +71,8 @@ function asmFunc(env) {
  function __wasm_ctz_i64($0, $1_1) {
   var $2 = 0, $3 = 0;
   if ($0 | $1_1) {
-   $2 = $1_1 + -1 | 0;
-   $3 = $0 + -1 | 0;
+   $2 = $1_1 - 1 | 0;
+   $3 = $0 - 1 | 0;
    $2 = ($3 | 0) != -1 ? $2 + 1 | 0 : $2;
    $3 = Math_clz32($0 ^ $3) + 32 | 0;
    $0 = Math_clz32($1_1 ^ $2);