wasm2js: Declare data segments before calling asmFunc (#3337)

This is because we maybe need to reference the segments
during the start function.  For example in the case of
pthreads we conditionally load passive segments during
start.

Tested in emscripten with: tests/runner.py wasm2js1

1 files changed, 26 insertions, 22 deletions

diff --git a/test/wasm2js/dynamicLibrary.2asm.js b/test/wasm2js/dynamicLibrary.2asm.js
index 5e743768d..03f8b79ed 100644
--- a/test/wasm2js/dynamicLibrary.2asm.js
+++ b/test/wasm2js/dynamicLibrary.2asm.js
@@ -12,6 +12,30 @@ function Table(ret) {
   return ret;
 }
 
+  var bufferView;
+  var base64ReverseLookup = new Uint8Array(123/*'z'+1*/);
+  for (var i = 25; i >= 0; --i) {
+    base64ReverseLookup[48+i] = 52+i; // '0-9'
+    base64ReverseLookup[65+i] = i; // 'A-Z'
+    base64ReverseLookup[97+i] = 26+i; // 'a-z'
+  }
+  base64ReverseLookup[43] = 62; // '+'
+  base64ReverseLookup[47] = 63; // '/'
+  /** @noinline Inlining this function would mean expanding the base64 string 4x times in the source code, which Closure seems to be happy to do. */
+  function base64DecodeToExistingUint8Array(uint8Array, offset, b64) {
+    var b1, b2, i = 0, j = offset, bLength = b64.length, end = offset + (bLength*3>>2) - (b64[bLength-2] == '=') - (b64[bLength-1] == '=');
+    for (; i < bLength; i += 4) {
+      b1 = base64ReverseLookup[b64.charCodeAt(i+1)];
+      b2 = base64ReverseLookup[b64.charCodeAt(i+2)];
+      uint8Array[j++] = base64ReverseLookup[b64.charCodeAt(i)] << 2 | b1 >> 4;
+      if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
+      if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
+    }
+    return uint8Array;
+  }
+function initActiveSegments(imports) {
+  base64DecodeToExistingUint8Array(bufferView, imports[memoryBase], "ZHluYW1pYyBkYXRh");
+}
 function asmFunc(env) {
  var memory = env.memory;
  var buffer = memory.buffer;
@@ -23,7 +47,6 @@ function asmFunc(env) {
  var HEAPU32 = new Uint32Array(buffer);
  var HEAPF32 = new Float32Array(buffer);
  var HEAPF64 = new Float64Array(buffer);
- bufferView = HEAPU8;
  var Math_imul = Math.imul;
  var Math_fround = Math.fround;
  var Math_abs = Math.abs;
@@ -51,6 +74,8 @@ function asmFunc(env) {
   
  }
  
+ bufferView = HEAPU8;
+ initActiveSegments(env);
  var FUNCTION_TABLE = Table(new Array(10));
  FUNCTION_TABLE[import$tableBase + 0] = foo;
  FUNCTION_TABLE[import$tableBase + 1] = bar;
@@ -64,29 +89,8 @@ function asmFunc(env) {
  };
 }
 
-var bufferView;
 var memasmFunc = new ArrayBuffer(16777216);
 var retasmFunc = asmFunc(  { abort: function() { throw new Error('abort'); },
     memory: { buffer : memasmFunc }
   });
-for (var base64ReverseLookup = new Uint8Array(123/*'z'+1*/), i = 25; i >= 0; --i) {
-    base64ReverseLookup[48+i] = 52+i; // '0-9'
-    base64ReverseLookup[65+i] = i; // 'A-Z'
-    base64ReverseLookup[97+i] = 26+i; // 'a-z'
-  }
-  base64ReverseLookup[43] = 62; // '+'
-  base64ReverseLookup[47] = 63; // '/'
-  /** @noinline Inlining this function would mean expanding the base64 string 4x times in the source code, which Closure seems to be happy to do. */
-  function base64DecodeToExistingUint8Array(uint8Array, offset, b64) {
-    var b1, b2, i = 0, j = offset, bLength = b64.length, end = offset + (bLength*3>>2) - (b64[bLength-2] == '=') - (b64[bLength-1] == '=');
-    for (; i < bLength; i += 4) {
-      b1 = base64ReverseLookup[b64.charCodeAt(i+1)];
-      b2 = base64ReverseLookup[b64.charCodeAt(i+2)];
-      uint8Array[j++] = base64ReverseLookup[b64.charCodeAt(i)] << 2 | b1 >> 4;
-      if (j < end) uint8Array[j++] = b1 << 4 | b2 >> 2;
-      if (j < end) uint8Array[j++] = b2 << 6 | base64ReverseLookup[b64.charCodeAt(i+3)];
-    }
-    return uint8Array;
-  }
-  base64DecodeToExistingUint8Array(bufferView, memoryBase, "ZHluYW1pYyBkYXRh");
 export var baz = retasmFunc.baz;