wasm2js: coerce function pointer indexes (#2979)

We emit FUNCTION_TABLE[ptr], where FUNCTION_TABLE is a JS
array. That is a rare case where true is handled differently than 1
(a typed array or an add would cast, etc.), so we must explicitly cast
there.

Fixes an issue that existed before, but became a problem due to
#2869 which optimized some selects into a form that emitted a true
or a false, and if that was a function pointer, it could be bad, see

https://app.circleci.com/pipelines/github/emscripten-core/emscripten/6699/workflows/0c4da49c-75d0-4b0a-8fac-686a8330a3fe/jobs/336520

The new test/wasm2js/indirect-select.2asm.js.opt output shows
what happened there.

Verified as passing emscripten's wasm2js1 wasm2js2 test suites.

1 files changed, 4 insertions, 4 deletions

diff --git a/test/wasm2js/ordering.2asm.js b/test/wasm2js/ordering.2asm.js
index 1fbfd0c03..f3d879a99 100644
--- a/test/wasm2js/ordering.2asm.js
+++ b/test/wasm2js/ordering.2asm.js
@@ -23,10 +23,10 @@ function asmFunc(global, env, buffer) {
  var infinity = global.Infinity;
  function main() {
   var wasm2js_i32$0 = 0, wasm2js_i32$1 = 0, wasm2js_i32$2 = 0;
-  FUNCTION_TABLE[foo(2 | 0) | 0](1) | 0;
-  FUNCTION_TABLE[4](foo(3 | 0) | 0) | 0;
-  (wasm2js_i32$1 = foo(5 | 0) | 0, wasm2js_i32$0 = bar(6 | 0) | 0), FUNCTION_TABLE[wasm2js_i32$0](wasm2js_i32$1 | 0) | 0;
-  FUNCTION_TABLE[8](7) | 0;
+  FUNCTION_TABLE[foo(2 | 0) | 0 | 0](1) | 0;
+  FUNCTION_TABLE[4 | 0](foo(3 | 0) | 0) | 0;
+  (wasm2js_i32$1 = foo(5 | 0) | 0, wasm2js_i32$0 = bar(6 | 0) | 0 | 0), FUNCTION_TABLE[wasm2js_i32$0](wasm2js_i32$1 | 0) | 0;
+  FUNCTION_TABLE[8 | 0](7) | 0;
   baz((11 ? 9 : 10) | 0) | 0;
   baz((wasm2js_i32$0 = foo(12 | 0) | 0, wasm2js_i32$1 = 13, wasm2js_i32$2 = 14, wasm2js_i32$2 ? wasm2js_i32$0 : wasm2js_i32$1) | 0) | 0;
   baz((wasm2js_i32$0 = 15, wasm2js_i32$1 = foo(16 | 0) | 0, wasm2js_i32$2 = 17, wasm2js_i32$2 ? wasm2js_i32$0 : wasm2js_i32$1) | 0) | 0;