Enable ConstraintAnalysis pass (#9010)

* Run it in -O3/-Os/-Oz.
* Update test expectations (one test improves slightly).

Fuzzed and validated on the emscripten test suite.

Fixes #9001

Author: kripken

src/passes/pass.cpp

@@ -740,6 +740,9 @@ void PassRunner::addDefaultFunctionOptimizationPasses() {
     "remove-unused-brs"); // coalesce-locals opens opportunities
   addIfNoDWARFIssues(
     "remove-unused-names");           // remove-unused-brs opens opportunities
+  if (options.optimizeLevel >= 3 || options.shrinkLevel >= 1) {
+    addIfNoDWARFIssues("constraint-analysis");
+  }
   addIfNoDWARFIssues("merge-blocks"); // clean up new blocks from last passes
   // late propagation
   if (options.optimizeLevel >= 3 || options.shrinkLevel >= 2) {