[vm] Bound the Simd sign mask result range

TEST=lib/typed_data/int32x4_sign_mask_test lib/typed_data/float32x4_sign_mask_test lib/typed_data/float64x2_sign_mask_test

Bug: #41950
Issue: #64170
Change-Id: Icf96d2b710b8518d2cedf5385d5e5966b30c68e5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/542363
Auto-Submit: Modestas Valauskas <valauskasmodestas@gmail.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>

Author: modulovalue

runtime/vm/compiler/backend/il.h

@@ -11340,6 +11340,8 @@ class SimdOpInstr : public Definition {
 
   virtual CompileType ComputeType() const;
 
+  virtual void InferRange(RangeAnalysis* analysis, Range* range);
+
   virtual bool MayThrow() const { return false; }
   virtual bool ComputeCanDeoptimize() const { return false; }
 

runtime/vm/compiler/backend/range_analysis.cc

@@ -2985,6 +2985,24 @@ void Utf8ScanInstr::InferRange(RangeAnalysis* analysis, Range* range) {
   *range = Range(RangeBoundary::FromConstant(0), RangeBoundary::MaxSmi());
 }
 
+void SimdOpInstr::InferRange(RangeAnalysis* analysis, Range* range) {
+  switch (kind()) {
+    // A sign mask has one bit per lane, so it is in [0, 2^lanes - 1].
+    case kInt32x4GetSignMask:
+    case kFloat32x4GetSignMask:
+      *range = Range(RangeBoundary::FromConstant(0),
+                     RangeBoundary::FromConstant(15));
+      break;
+    case kFloat64x2GetSignMask:
+      *range =
+          Range(RangeBoundary::FromConstant(0), RangeBoundary::FromConstant(3));
+      break;
+    default:
+      Definition::InferRange(analysis, range);
+      break;
+  }
+}
+
 void IfThenElseInstr::InferRange(RangeAnalysis* analysis, Range* range) {
   const intptr_t min = Utils::Minimum(if_true_, if_false_);
   const intptr_t max = Utils::Maximum(if_true_, if_false_);