Bug 1121299 - Let GVN fold MSimdBox when it can fold MSimdConstants. r=sunfish

js/src/jit-test/tests/ion/simd-bug1121299.js

@@ -0,0 +1,28 @@
+setJitCompilerOption("baseline.warmup.trigger", 10);
+setJitCompilerOption("ion.warmup.trigger", 30);
+
+function test_1(i) {
+  if (i >= 40)
+    return;
+  var a = SIMD.float32x4(1.1, 2.2, 3.3, 4.6);
+  SIMD.int32x4.fromFloat32x4(a);
+  test_1(i + 1);
+}
+test_1(0);
+
+
+var float32x4 = SIMD.float32x4;
+function test_2() {
+    var Array = float32x4.array(3);
+    var array = new Array([
+        float32x4(1, 2, 3, 4),
+        float32x4(5, 6, 7, 8),
+        float32x4(9, 10, 11, 12)
+    ]);
+    if (typeof reportCompare === "function")
+        reportCompare(true, true);
+}
+test_2();
+evaluate("test_2(); test_2();", {
+    compileAndGo: true
+});

js/src/jit/MIR.h

@@ -2963,6 +2963,17 @@ class MSimdBox
         return initialHeap_;
     }
 
+    bool congruentTo(const MDefinition *ins) const MOZ_OVERRIDE {
+        if (congruentIfOperandsEqual(ins)) {
+            MOZ_ASSERT(ins->toSimdBox()->initialHeap() == initialHeap());
+            // The template object is likely to be different, but represents the
+            // same kind of objects as the MIRTypes are identical.
+            return true;
+        }
+
+        return false;
+    }
+
     AliasSet getAliasSet() const MOZ_OVERRIDE {
         return AliasSet::None();
     }