diff --git a/runtime/platform/utils.h b/runtime/platform/utils.h
index a1d6b1b..84366eb 100644
--- a/runtime/platform/utils.h
+++ b/runtime/platform/utils.h
@@ -417,34 +417,26 @@
     return ((-0x20000000000000LL <= value) && (value <= 0x20000000000000LL));
   }
 
-  static constexpr uword NBitMaskUnsafe(uint32_t n) {
-    static_assert((sizeof(uword) * kBitsPerByte) == kBitsPerWord,
-                  "Unexpected uword size");
-    return n == kBitsPerWord ? std::numeric_limits<uword>::max()
-                             : (static_cast<uword>(1) << n) - 1;
-  }
-
   // The lowest n bits are 1, the others are 0.
-  static uword NBitMask(uint32_t n) {
-    ASSERT(n <= kBitsPerWord);
-    return NBitMaskUnsafe(n);
-  }
-
-  static word SignedNBitMask(uint32_t n) {
-    uword mask = NBitMask(n);
-    return bit_cast<word>(mask);
+  template <typename T = uword>
+  static constexpr T NBitMask(size_t n) {
+    using Unsigned = typename std::make_unsigned<T>::type;
+    constexpr size_t kBitsPerT = sizeof(T) * kBitsPerByte;
+    assert(n <= sizeof(T) * kBitsPerT);
+    return static_cast<T>(n == kBitsPerT ? std::numeric_limits<Unsigned>::max()
+                                         : (static_cast<Unsigned>(1) << n) - 1);
   }
 
   template <typename T = uword>
-  static T Bit(uint32_t n) {
+  static constexpr T Bit(size_t n) {
     ASSERT(n < sizeof(T) * kBitsPerByte);
     T bit = 1;
     return bit << n;
   }
 
   template <typename T>
-  DART_FORCE_INLINE static bool TestBit(T mask, intptr_t position) {
-    ASSERT(position < static_cast<intptr_t>(sizeof(T) * kBitsPerByte));
+  static constexpr bool TestBit(T mask, size_t position) {
+    ASSERT(position < sizeof(T) * kBitsPerByte);
     return ((mask >> position) & 1) != 0;
   }
 
diff --git a/runtime/vm/code_descriptors.h b/runtime/vm/code_descriptors.h
index 0d15c38..ac29be7 100644
--- a/runtime/vm/code_descriptors.h
+++ b/runtime/vm/code_descriptors.h
@@ -209,7 +209,7 @@
   using ArgField = BitField<int32_t, int32_t, OpField::kNextBit>;
 
   static constexpr int32_t kMaxArgValue =
-      Utils::NBitMaskUnsafe(ArgField::bitsize() - 1);
+      Utils::NBitMask<int32_t>(ArgField::bitsize() - 1);
   static constexpr int32_t kMinArgValue = ~kMaxArgValue;
   static constexpr int32_t kSignBits = static_cast<uint32_t>(kMinArgValue) << 1;
 };
diff --git a/runtime/vm/compiler/backend/il_arm.cc b/runtime/vm/compiler/backend/il_arm.cc
index 0c07ad2..5ede916 100644
--- a/runtime/vm/compiler/backend/il_arm.cc
+++ b/runtime/vm/compiler/backend/il_arm.cc
@@ -779,8 +779,8 @@
   const intptr_t kCpuRegistersToPreserve =
       kDartAvailableCpuRegs & ~kNonChangeableInputRegs;
   const intptr_t kFpuRegistersToPreserve =
-      Utils::SignedNBitMask(kNumberOfFpuRegisters) &
-      ~(Utils::SignedNBitMask(kAbiPreservedFpuRegCount)
+      Utils::NBitMask<intptr_t>(kNumberOfFpuRegisters) &
+      ~(Utils::NBitMask<intptr_t>(kAbiPreservedFpuRegCount)
         << kAbiFirstPreservedFpuReg) &
       ~(1 << FpuTMP);
 
diff --git a/runtime/vm/compiler/backend/il_arm64.cc b/runtime/vm/compiler/backend/il_arm64.cc
index d8cebd7..9484c260 100644
--- a/runtime/vm/compiler/backend/il_arm64.cc
+++ b/runtime/vm/compiler/backend/il_arm64.cc
@@ -699,7 +699,7 @@
   const intptr_t kCpuRegistersToPreserve =
       kDartAvailableCpuRegs & ~kNonChangeableInputRegs;
   const intptr_t kFpuRegistersToPreserve =
-      Utils::SignedNBitMask(kNumberOfFpuRegisters) & ~(1l << FpuTMP);
+      Utils::NBitMask<intptr_t>(kNumberOfFpuRegisters) & ~(1l << FpuTMP);
 
   const intptr_t kNumTemps = (Utils::CountOneBits64(kCpuRegistersToPreserve) +
                               Utils::CountOneBits64(kFpuRegistersToPreserve));
diff --git a/runtime/vm/v8_snapshot_writer.h b/runtime/vm/v8_snapshot_writer.h
index 644a2e0..c69abdc 100644
--- a/runtime/vm/v8_snapshot_writer.h
+++ b/runtime/vm/v8_snapshot_writer.h
@@ -58,7 +58,8 @@
    private:
     static constexpr size_t kIdSpaceBits =
         Utils::BitLength(static_cast<int64_t>(IdSpace::kArtificial));
-    static constexpr int64_t kIdSpaceMask = Utils::NBitMaskUnsafe(kIdSpaceBits);
+    static constexpr int64_t kIdSpaceMask =
+        Utils::NBitMask<int64_t>(kIdSpaceBits);
     static const char* IdSpaceToCString(IdSpace space);
 
     int64_t encoded_;