2 files changed, 9 insertions, 4 deletions
diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index 8daa46c09a..9cfc16f596 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -235,7 +235,10 @@ void InstructionSimplifierVisitor::VisitShift(HBinaryOperation* instruction) {
   HInstruction* input_other = instruction->GetLeastConstantLeft();
 
   if (input_cst != nullptr) {
-    if (input_cst->IsZero()) {
+    int64_t cst = Int64FromConstant(input_cst);
+    int64_t mask =
+        (input_other->GetType() == Primitive::kPrimLong) ? kMaxLongShiftValue : kMaxIntShiftValue;
+    if ((cst & mask) == 0) {
       // Replace code looking like
       //    SHL dst, src, 0
       // with
@@ -513,7 +516,9 @@ void InstructionSimplifierVisitor::VisitInstanceOf(HInstanceOf* instruction) {
     return;
   }
 
-  bool outcome;
+  // Note: The `outcome` is initialized to please valgrind - the compiler can reorder
+  // the return value check with the `outcome` check, b/27651442 .
+  bool outcome = false;
   if (TypeCheckHasKnownOutcome(load_class, object, &outcome)) {
     if (outcome && can_be_null) {
       // Type test will succeed, we just need a null test.
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 4ac8f9869f..3733850745 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -2543,7 +2543,7 @@ class HFloatConstant : public HConstant {
     return bit_cast<uint32_t, float>(value_) == bit_cast<uint32_t, float>((-1.0f));
   }
   bool IsZero() const OVERRIDE {
-    return value_ == 0.0f;
+    return bit_cast<uint32_t, float>(value_) == bit_cast<uint32_t, float>(0.0f);
   }
   bool IsOne() const OVERRIDE {
     return bit_cast<uint32_t, float>(value_) == bit_cast<uint32_t, float>(1.0f);
@@ -2585,7 +2585,7 @@ class HDoubleConstant : public HConstant {
     return bit_cast<uint64_t, double>(value_) == bit_cast<uint64_t, double>((-1.0));
   }
   bool IsZero() const OVERRIDE {
-    return value_ == 0.0;
+    return bit_cast<uint64_t, double>(value_) == bit_cast<uint64_t, double>((0.0));
   }
   bool IsOne() const OVERRIDE {
     return bit_cast<uint64_t, double>(value_) == bit_cast<uint64_t, double>(1.0);