Rename `wasm2asm` to `wasm2js`, emit ESM by default (#1642)

* Rename the `wasm2asm` tool to `wasm2js`

This commit performs a relatively simple rename of the `wasm2asm` tool to
`wasm2js`. The functionality of the tool doesn't change just yet but it's
intended that we'll start generating an ES module instead of just an `asm.js`
function soon.

* wasm2js: Support `*.wasm` input files

Previously `wasm2js` only supported `*.wast` files but to make it a bit easier
to use in tooling pipelines this commit adds support for reading in a `*.wasm`
file directly. Determining which parser to use depends on the input filename,
where the binary parser is used with `*.wasm` files and the wast parser is used
for all other files.

* wasm2js: Emit ESM imports/exports by default

This commit alters the default behavior of `wasm2js` to emit an ESM by default,
either importing items from the environment or exporting. Items like
initialization of memory are also handled here.

1 files changed, 178 insertions, 0 deletions

diff --git a/test/wasm2js/int_literals.2asm.js b/test/wasm2js/int_literals.2asm.js
new file mode 100644
index 000000000..0d0b19f97
--- /dev/null
+++ b/test/wasm2js/int_literals.2asm.js
@@ -0,0 +1,178 @@
+function asmFunc(global, env, buffer) {
+ "use asm";
+ var HEAP8 = new global.Int8Array(buffer);
+ var HEAP16 = new global.Int16Array(buffer);
+ var HEAP32 = new global.Int32Array(buffer);
+ var HEAPU8 = new global.Uint8Array(buffer);
+ var HEAPU16 = new global.Uint16Array(buffer);
+ var HEAPU32 = new global.Uint32Array(buffer);
+ var HEAPF32 = new global.Float32Array(buffer);
+ var HEAPF64 = new global.Float64Array(buffer);
+ var Math_imul = global.Math.imul;
+ var Math_fround = global.Math.fround;
+ var Math_abs = global.Math.abs;
+ var Math_clz32 = global.Math.clz32;
+ var Math_min = global.Math.min;
+ var Math_max = global.Math.max;
+ var Math_floor = global.Math.floor;
+ var Math_ceil = global.Math.ceil;
+ var Math_sqrt = global.Math.sqrt;
+ var abort = env.abort;
+ var nan = global.NaN;
+ var infinity = global.Infinity;
+ var i64toi32_i32$HIGH_BITS = 0;
+ function $0() {
+  return 195940365 | 0;
+ }
+ 
+ function $1() {
+  return 4294967295 | 0;
+ }
+ 
+ function $2() {
+  return 2147483647 | 0;
+ }
+ 
+ function $3() {
+  return 2147483649 | 0;
+ }
+ 
+ function $4() {
+  return 2147483648 | 0;
+ }
+ 
+ function $5() {
+  return 2147483648 | 0;
+ }
+ 
+ function $6() {
+  return 2147483648 + 1 | 0 | 0;
+ }
+ 
+ function $7() {
+  return 0 | 0;
+ }
+ 
+ function $8() {
+  return 10 | 0;
+ }
+ 
+ function $9() {
+  return 4294967295 | 0;
+ }
+ 
+ function $10() {
+  return 42 | 0;
+ }
+ 
+ function $11() {
+  i64toi32_i32$HIGH_BITS = 212580974;
+  return 195455598 | 0;
+ }
+ 
+ function $12() {
+  i64toi32_i32$HIGH_BITS = 4294967295;
+  return 4294967295 | 0;
+ }
+ 
+ function $13() {
+  i64toi32_i32$HIGH_BITS = 2147483647;
+  return 4294967295 | 0;
+ }
+ 
+ function $14() {
+  i64toi32_i32$HIGH_BITS = 2147483648;
+  return 1 | 0;
+ }
+ 
+ function $15() {
+  i64toi32_i32$HIGH_BITS = 2147483648;
+  return 0 | 0;
+ }
+ 
+ function $16() {
+  i64toi32_i32$HIGH_BITS = 2147483648;
+  return 0 | 0;
+ }
+ 
+ function $17() {
+  var i64toi32_i32$5 = 0, i64toi32_i32$4 = 0, i64toi32_i32$3 = 0;
+  i64toi32_i32$3 = 1;
+  i64toi32_i32$4 = 0 + i64toi32_i32$3 | 0;
+  i64toi32_i32$5 = 2147483648 + 0 | 0;
+  if (i64toi32_i32$4 >>> 0 < i64toi32_i32$3 >>> 0) i64toi32_i32$5 = i64toi32_i32$5 + 1 | 0;
+  i64toi32_i32$5 = i64toi32_i32$5;
+  i64toi32_i32$HIGH_BITS = i64toi32_i32$5;
+  return i64toi32_i32$4 | 0;
+ }
+ 
+ function $18() {
+  i64toi32_i32$HIGH_BITS = 0;
+  return 0 | 0;
+ }
+ 
+ function $19() {
+  i64toi32_i32$HIGH_BITS = 0;
+  return 10 | 0;
+ }
+ 
+ function $20() {
+  i64toi32_i32$HIGH_BITS = 4294967295;
+  return 4294967295 | 0;
+ }
+ 
+ function $21() {
+  i64toi32_i32$HIGH_BITS = 0;
+  return 42 | 0;
+ }
+ 
+ return {
+  i32_test: $0, 
+  i32_umax: $1, 
+  i32_smax: $2, 
+  i32_neg_smax: $3, 
+  i32_smin: $4, 
+  i32_alt_smin: $5, 
+  i32_inc_smin: $6, 
+  i32_neg_zero: $7, 
+  i32_not_octal: $8, 
+  i32_unsigned_decimal: $9, 
+  i32_plus_sign: $10, 
+  i64_test: $11, 
+  i64_umax: $12, 
+  i64_smax: $13, 
+  i64_neg_smax: $14, 
+  i64_smin: $15, 
+  i64_alt_smin: $16, 
+  i64_inc_smin: $17, 
+  i64_neg_zero: $18, 
+  i64_not_octal: $19, 
+  i64_unsigned_decimal: $20, 
+  i64_plus_sign: $21
+ };
+}
+
+const memasmFunc = new ArrayBuffer(65536);
+const retasmFunc = asmFunc({Math,Int8Array,Uint8Array,Int16Array,Uint16Array,Int32Array,Uint32Array,Float32Array,Float64Array,NaN,Infinity}, {abort:function() { throw new Error('abort'); }},memasmFunc);
+export const i32_test = retasmFunc.i32_test;
+export const i32_umax = retasmFunc.i32_umax;
+export const i32_smax = retasmFunc.i32_smax;
+export const i32_neg_smax = retasmFunc.i32_neg_smax;
+export const i32_smin = retasmFunc.i32_smin;
+export const i32_alt_smin = retasmFunc.i32_alt_smin;
+export const i32_inc_smin = retasmFunc.i32_inc_smin;
+export const i32_neg_zero = retasmFunc.i32_neg_zero;
+export const i32_not_octal = retasmFunc.i32_not_octal;
+export const i32_unsigned_decimal = retasmFunc.i32_unsigned_decimal;
+export const i32_plus_sign = retasmFunc.i32_plus_sign;
+export const i64_test = retasmFunc.i64_test;
+export const i64_umax = retasmFunc.i64_umax;
+export const i64_smax = retasmFunc.i64_smax;
+export const i64_neg_smax = retasmFunc.i64_neg_smax;
+export const i64_smin = retasmFunc.i64_smin;
+export const i64_alt_smin = retasmFunc.i64_alt_smin;
+export const i64_inc_smin = retasmFunc.i64_inc_smin;
+export const i64_neg_zero = retasmFunc.i64_neg_zero;
+export const i64_not_octal = retasmFunc.i64_not_octal;
+export const i64_unsigned_decimal = retasmFunc.i64_unsigned_decimal;
+export const i64_plus_sign = retasmFunc.i64_plus_sign;