use simplify-locals in wasm2asm, so the output is not horribly verbose with los of extra inefficient variables. this is more similar to the output we had before the flatten rewrite (#1229)

Author: kripken

src/wasm2asm.h

@@ -387,6 +387,7 @@ Ref Wasm2AsmBuilder::processWasm(Module* wasm) {
   runner.add<AutoDrop>();
   runner.add("i64-to-i32-lowering");
   runner.add("flatten");
+  runner.add("simplify-locals-notee-nostructure");
   runner.add("vacuum");
   runner.setDebug(flags.debug);
   runner.run();

test/address.2asm.js

@@ -16,70 +16,32 @@ function asmFunc(global, env, buffer) {
  function $$0(i) {
   i = i | 0;
   var $$1 = 0, $$2 = 0, $$3 = 0, $$4 = 0, $$5 = 0, $$6 = 0, $$7 = 0, $$8 = 0, $$9 = 0, $$10 = 0, $$11 = 0, $$12 = 0, $$13 = 0, $$14 = 0, $$15 = 0, $$16 = 0, $$17 = 0, $$18 = 0, $$19 = 0, $$20 = 0, $$21 = 0, $$22 = 0, $$23 = 0, $$24 = 0, $$25 = 0, $$26 = 0, wasm2asm_i32$0 = 0;
-  $$1 = i;
-  $$2 = HEAPU8[$$1 >> 0] | 0;
-  print($$2 | 0);
-  $$3 = i;
-  $$4 = HEAPU8[($$3 + 1 | 0) >> 0] | 0;
-  print($$4 | 0);
-  $$5 = i;
-  $$6 = HEAPU8[($$5 + 2 | 0) >> 0] | 0;
-  print($$6 | 0);
-  $$7 = i;
-  $$8 = HEAPU8[($$7 + 25 | 0) >> 0] | 0;
-  print($$8 | 0);
-  $$9 = i;
-  $$10 = HEAPU16[$$9 >> 1] | 0;
-  print($$10 | 0);
-  $$11 = i;
-  $$12 = (wasm2asm_i32$0 = $$11, HEAPU8[wasm2asm_i32$0 >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 1 | 0) >> 0] | 0 | 0) << 8);
-  print($$12 | 0);
-  $$13 = i;
-  $$14 = (wasm2asm_i32$0 = $$13, HEAPU8[(wasm2asm_i32$0 + 1 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 2 | 0) >> 0] | 0 | 0) << 8);
-  print($$14 | 0);
-  $$15 = i;
-  $$16 = HEAPU16[($$15 + 2 | 0) >> 1] | 0;
-  print($$16 | 0);
-  $$17 = i;
-  $$18 = (wasm2asm_i32$0 = $$17, HEAPU8[(wasm2asm_i32$0 + 25 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 26 | 0) >> 0] | 0 | 0) << 8);
-  print($$18 | 0);
-  $$19 = i;
-  $$20 = HEAPU32[$$19 >> 2] | 0;
-  print($$20 | 0);
-  $$21 = i;
-  $$22 = (wasm2asm_i32$0 = $$21, HEAPU8[(wasm2asm_i32$0 + 1 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 2 | 0) >> 0] | 0 | 0) << 8 | (HEAPU8[(wasm2asm_i32$0 + 3 | 0) >> 0] | 0 | 0) << 16 | (HEAPU8[(wasm2asm_i32$0 + 4 | 0) >> 0] | 0 | 0) << 24);
-  print($$22 | 0);
-  $$23 = i;
-  $$24 = (wasm2asm_i32$0 = $$23, HEAPU8[(wasm2asm_i32$0 + 2 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 3 | 0) >> 0] | 0 | 0) << 8 | (HEAPU8[(wasm2asm_i32$0 + 4 | 0) >> 0] | 0 | 0) << 16 | (HEAPU8[(wasm2asm_i32$0 + 5 | 0) >> 0] | 0 | 0) << 24);
-  print($$24 | 0);
-  $$25 = i;
-  $$26 = (wasm2asm_i32$0 = $$25, HEAPU8[(wasm2asm_i32$0 + 25 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 26 | 0) >> 0] | 0 | 0) << 8 | (HEAPU8[(wasm2asm_i32$0 + 27 | 0) >> 0] | 0 | 0) << 16 | (HEAPU8[(wasm2asm_i32$0 + 28 | 0) >> 0] | 0 | 0) << 24);
-  print($$26 | 0);
+  print(HEAPU8[i >> 0] | 0 | 0);
+  print(HEAPU8[(i + 1 | 0) >> 0] | 0 | 0);
+  print(HEAPU8[(i + 2 | 0) >> 0] | 0 | 0);
+  print(HEAPU8[(i + 25 | 0) >> 0] | 0 | 0);
+  print(HEAPU16[i >> 1] | 0 | 0);
+  print((wasm2asm_i32$0 = i, HEAPU8[wasm2asm_i32$0 >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 1 | 0) >> 0] | 0 | 0) << 8) | 0);
+  print((wasm2asm_i32$0 = i, HEAPU8[(wasm2asm_i32$0 + 1 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 2 | 0) >> 0] | 0 | 0) << 8) | 0);
+  print(HEAPU16[(i + 2 | 0) >> 1] | 0 | 0);
+  print((wasm2asm_i32$0 = i, HEAPU8[(wasm2asm_i32$0 + 25 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 26 | 0) >> 0] | 0 | 0) << 8) | 0);
+  print(HEAPU32[i >> 2] | 0 | 0);
+  print((wasm2asm_i32$0 = i, HEAPU8[(wasm2asm_i32$0 + 1 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 2 | 0) >> 0] | 0 | 0) << 8 | (HEAPU8[(wasm2asm_i32$0 + 3 | 0) >> 0] | 0 | 0) << 16 | (HEAPU8[(wasm2asm_i32$0 + 4 | 0) >> 0] | 0 | 0) << 24) | 0);
+  print((wasm2asm_i32$0 = i, HEAPU8[(wasm2asm_i32$0 + 2 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 3 | 0) >> 0] | 0 | 0) << 8 | (HEAPU8[(wasm2asm_i32$0 + 4 | 0) >> 0] | 0 | 0) << 16 | (HEAPU8[(wasm2asm_i32$0 + 5 | 0) >> 0] | 0 | 0) << 24) | 0);
+  print((wasm2asm_i32$0 = i, HEAPU8[(wasm2asm_i32$0 + 25 | 0) >> 0] | 0 | 0 | (HEAPU8[(wasm2asm_i32$0 + 26 | 0) >> 0] | 0 | 0) << 8 | (HEAPU8[(wasm2asm_i32$0 + 27 | 0) >> 0] | 0 | 0) << 16 | (HEAPU8[(wasm2asm_i32$0 + 28 | 0) >> 0] | 0 | 0) << 24) | 0);
  }
 
  function $$1(i) {
   i = i | 0;
   var $$1 = 0, $$2 = 0;
-  $$1 = i;
-  $$2 = HEAPU32[($$1 + 4294967295 | 0) >> 2] | 0;
+  HEAPU32[(i + 4294967295 | 0) >> 2] | 0;
  }
 
  function __wasm_ctz_i32(x) {
   x = x | 0;
   var $$1 = 0, $$2 = 0, $$3 = 0, $$4 = 0, $$5 = 0, $$6 = 0, $$7 = 0, $$8 = 0, $$9 = 0, $$10 = 0;
-  $$1 = x;
-  $$2 = ($$1 | 0) == (0 | 0);
-  if ($$2) $$9 = 32; else {
-   $$3 = x;
-   $$4 = x;
-   $$5 = $$4 - 1 | 0;
-   $$6 = $$3 ^ $$5 | 0;
-   $$7 = Math_clz32($$6);
-   $$8 = 31 - $$7 | 0;
-   $$9 = $$8;
-  }
-  $$10 = $$9;
-  return $$10 | 0;
+  if ((x | 0) == (0 | 0)) $$9 = 32; else $$9 = 31 - Math_clz32(x ^ (x - 1 | 0) | 0) | 0;
+  return $$9 | 0;
  }
 
  function __wasm_popcnt_i32(x) {
@@ -88,80 +50,31 @@ function asmFunc(global, env, buffer) {
   count = 0;
   b : {
    l : do {
-    $$2 = count;
-    $$3 = x;
-    $$4 = ($$3 | 0) == (0 | 0);
-    $$5 = $$2;
-    if ($$4) break b;
-    $$6 = $$5;
-    $$7 = x;
-    $$8 = x;
-    $$9 = $$8 - 1 | 0;
-    $$10 = $$7 & $$9 | 0;
-    x = $$10;
-    $$11 = count;
-    $$12 = $$11 + 1 | 0;
-    count = $$12;
+    $$5 = count;
+    if ((x | 0) == (0 | 0)) break b;
+    x = x & (x - 1 | 0) | 0;
+    count = count + 1 | 0;
     continue l;
     break l;
    } while (1);
   };
-  $$13 = $$5;
-  $$14 = $$13;
-  $$15 = $$14;
-  return $$15 | 0;
+  return $$5 | 0;
  }
 
  function __wasm_rotl_i32(x, k) {
   x = x | 0;
   k = k | 0;
-  var $$2 = 0, $$3 = 0, $$4 = 0, $$5 = 0, $$6 = 0, $$7 = 0, $$8 = 0, $$9 = 0, $$10 = 0, $$11 = 0, $$12 = 0, $$13 = 0, $$14 = 0, $$15 = 0, $$16 = 0, $$17 = 0, $$18 = 0, $$19 = 0, $$20 = 0;
-  $$2 = k;
-  $$3 = $$2 & 31 | 0;
-  $$4 = 4294967295 >>> $$3 | 0;
-  $$5 = x;
-  $$6 = $$4 & $$5 | 0;
-  $$7 = k;
-  $$8 = $$7 & 31 | 0;
-  $$9 = $$6 << $$8 | 0;
-  $$10 = k;
-  $$11 = $$10 & 31 | 0;
-  $$12 = 32 - $$11 | 0;
-  $$13 = 4294967295 << $$12 | 0;
-  $$14 = x;
-  $$15 = $$13 & $$14 | 0;
-  $$16 = k;
-  $$17 = $$16 & 31 | 0;
-  $$18 = 32 - $$17 | 0;
-  $$19 = $$15 >>> $$18 | 0;
-  $$20 = $$9 | $$19 | 0;
-  return $$20 | 0;
+  var $$2 = 0, $$3 = 0, $$4 = 0, $$5 = 0, $$6 = 0, $$7 = 0, $$8 = 0, $$9 = 0, $$10 = 0, $$11 = 0, $$12 = 0, $$13 = 0, $$14 = 0, $$15 = 0, $$16 = 0, $$17 = 0, $$18 = 0, $$19 = 0, $$20 = 0, wasm2asm_i32$0 = 0;
+  return ((4294967295 >>> (k & 31 | 0) | 0) & x | 0) << (k & 31 | 0) | 0 | (((4294967295 << (32 - (k & 31 | 0) | 0) | 0) & x | 0) >>> (32 - (k & 31 | 0) | 0) | 0) | 0 | 0;
+  return wasm2asm_i32$0 | 0;
  }
 
  function __wasm_rotr_i32(x, k) {
   x = x | 0;
   k = k | 0;
-  var $$2 = 0, $$3 = 0, $$4 = 0, $$5 = 0, $$6 = 0, $$7 = 0, $$8 = 0, $$9 = 0, $$10 = 0, $$11 = 0, $$12 = 0, $$13 = 0, $$14 = 0, $$15 = 0, $$16 = 0, $$17 = 0, $$18 = 0, $$19 = 0, $$20 = 0;
-  $$2 = k;
-  $$3 = $$2 & 31 | 0;
-  $$4 = 4294967295 << $$3 | 0;
-  $$5 = x;
-  $$6 = $$4 & $$5 | 0;
-  $$7 = k;
-  $$8 = $$7 & 31 | 0;
-  $$9 = $$6 >>> $$8 | 0;
-  $$10 = k;
-  $$11 = $$10 & 31 | 0;
-  $$12 = 32 - $$11 | 0;
-  $$13 = 4294967295 >>> $$12 | 0;
-  $$14 = x;
-  $$15 = $$13 & $$14 | 0;
-  $$16 = k;
-  $$17 = $$16 & 31 | 0;
-  $$18 = 32 - $$17 | 0;
-  $$19 = $$15 << $$18 | 0;
-  $$20 = $$9 | $$19 | 0;
-  return $$20 | 0;
+  var $$2 = 0, $$3 = 0, $$4 = 0, $$5 = 0, $$6 = 0, $$7 = 0, $$8 = 0, $$9 = 0, $$10 = 0, $$11 = 0, $$12 = 0, $$13 = 0, $$14 = 0, $$15 = 0, $$16 = 0, $$17 = 0, $$18 = 0, $$19 = 0, $$20 = 0, wasm2asm_i32$0 = 0;
+  return ((4294967295 << (k & 31 | 0) | 0) & x | 0) >>> (k & 31 | 0) | 0 | (((4294967295 >>> (32 - (k & 31 | 0) | 0) | 0) & x | 0) << (32 - (k & 31 | 0) | 0) | 0) | 0 | 0;
+  return wasm2asm_i32$0 | 0;
  }
 
  return {