[slimtensor] Add all required dtype support (Int8/16/32/64, Bool, BFloat16)

This diff adds support for all required scalar types in SlimTensor to support ExecuTorch aoti-driven backend usage: Int8 (Char), Int16 (Short), Int32 (Int), Int64 (Long), Bool, and BFloat16.

**Key changes:**

1. **`c10/core/ScalarType.h`** - Extended with all required types:
   - Added enum values matching PyTorch's c10::ScalarType for compatibility
   - Added type alias constants (kChar, kShort, kInt, kLong, kBool, kBFloat16)
   - Extended `elementSize()` to return correct sizes for all types
   - Extended `toString()` for all types
   - Fixed `isFloatingType()` to include BFloat16
   - Fixed `isIntegralType()` to properly handle all integral types and Bool
   - Added `isBoolType()` helper function
   - Imported BFloat16 from ExecuTorch's portable_type

Differential Revision: [D89821402](https://our.internmc.facebook.com/intern/diff/D89821402/)

ghstack-source-id: 331195238
Pull Request resolved: #16399

Author: Gasoonjia

backends/aoti/slim/c10/core/ScalarType.h

@@ -12,35 +12,64 @@
 #include <cstdint>
 #include <ostream>
 
+#include <executorch/runtime/core/portable_type/bfloat16.h>
 #include <executorch/runtime/platform/assert.h>
 
 namespace executorch::backends::aoti::slim::c10 {
 
+// Import BFloat16 from ExecuTorch's portable_type
+using BFloat16 = ::executorch::runtime::etensor::BFloat16;
+
 /// Enum representing the scalar type (dtype) of tensor elements.
 /// Note: Enum values must match PyTorch's c10::ScalarType for compatibility.
 enum class ScalarType : int8_t {
-  // Byte = 0,
-  // Char = 1,
-  // Short = 2,
-  // Int = 3,
-  // Long = 4,
-  Float = 6,
-  // Bool = 11,
-  // BFloat16 = 15,
+  // Byte = 0,     // uint8_t - not currently needed
+  Char = 1, // int8_t
+  Short = 2, // int16_t
+  Int = 3, // int32_t
+  Long = 4, // int64_t
+  // Half = 5,     // float16 - not currently needed
+  Float = 6, // float
+  // Double = 7,   // double - not currently needed
+  // ComplexHalf = 8,
+  // ComplexFloat = 9,
+  // ComplexDouble = 10,
+  Bool = 11, // bool
+  // QInt8 = 12,
+  // QUInt8 = 13,
+  // QInt32 = 14,
+  BFloat16 = 15, // bfloat16
   Undefined = -1,
-  NumOptions = 7,
 };
 
-/// Constant for Float scalar type.
+// Type alias constants for convenience
+constexpr ScalarType kChar = ScalarType::Char;
+constexpr ScalarType kShort = ScalarType::Short;
+constexpr ScalarType kInt = ScalarType::Int;
+constexpr ScalarType kLong = ScalarType::Long;
 constexpr ScalarType kFloat = ScalarType::Float;
+constexpr ScalarType kBool = ScalarType::Bool;
+constexpr ScalarType kBFloat16 = ScalarType::BFloat16;
 
 /// Returns the size in bytes of a single element of the given scalar type.
 /// @param t The scalar type.
 /// @return The size in bytes of a single element.
 inline size_t elementSize(ScalarType t) {
   switch (t) {
+    case ScalarType::Char:
+      return sizeof(int8_t);
+    case ScalarType::Short:
+      return sizeof(int16_t);
+    case ScalarType::Int:
+      return sizeof(int32_t);
+    case ScalarType::Long:
+      return sizeof(int64_t);
     case ScalarType::Float:
       return sizeof(float);
+    case ScalarType::Bool:
+      return sizeof(bool);
+    case ScalarType::BFloat16:
+      return sizeof(BFloat16);
     default:
       ET_CHECK_MSG(false, "Unknown ScalarType: %d", static_cast<int>(t));
   }
@@ -51,8 +80,20 @@ inline size_t elementSize(ScalarType t) {
 /// @return The name of the scalar type.
 inline const char* toString(ScalarType t) {
   switch (t) {
+    case ScalarType::Char:
+      return "Char";
+    case ScalarType::Short:
+      return "Short";
+    case ScalarType::Int:
+      return "Int";
+    case ScalarType::Long:
+      return "Long";
     case ScalarType::Float:
       return "Float";
+    case ScalarType::Bool:
+      return "Bool";
+    case ScalarType::BFloat16:
+      return "BFloat16";
     case ScalarType::Undefined:
       return "Undefined";
     default:
@@ -64,16 +105,32 @@ inline const char* toString(ScalarType t) {
 /// @param t The scalar type to check.
 /// @return true if the scalar type is floating point, false otherwise.
 inline bool isFloatingType(ScalarType t) {
-  return t == ScalarType::Float;
+  return t == ScalarType::Float || t == ScalarType::BFloat16;
 }
 
-/// Checks if the scalar type is an integral type (including bool).
+/// Checks if the scalar type is an integral type (including bool optionally).
 /// @param t The scalar type to check.
 /// @param includeBool Whether to consider Bool as integral.
 /// @return true if the scalar type is integral, false otherwise.
-inline bool isIntegralType(ScalarType t, bool /*includeBool*/) {
-  (void)t;
-  return false;
+inline bool isIntegralType(ScalarType t, bool includeBool) {
+  switch (t) {
+    case ScalarType::Char:
+    case ScalarType::Short:
+    case ScalarType::Int:
+    case ScalarType::Long:
+      return true;
+    case ScalarType::Bool:
+      return includeBool;
+    default:
+      return false;
+  }
+}
+
+/// Checks if the scalar type is a boolean type.
+/// @param t The scalar type to check.
+/// @return true if the scalar type is Bool, false otherwise.
+inline bool isBoolType(ScalarType t) {
+  return t == ScalarType::Bool;
 }
 
 inline std::ostream& operator<<(std::ostream& stream, ScalarType scalar_type) {

backends/aoti/slim/c10/core/targets.bzl

@@ -36,6 +36,7 @@ def define_common_targets():
         ],
         visibility = ["@EXECUTORCH_CLIENTS"],
         exported_deps = [
+            "//executorch/runtime/core/portable_type:portable_type",
             "//executorch/runtime/platform:platform",
         ],
     )

backends/aoti/slim/c10/core/test/test_scalar_type.cpp

@@ -13,49 +13,186 @@
 
 using namespace executorch::backends::aoti::slim::c10;
 
-class ScalarTypeTest : public ::testing::Test {};
+// =============================================================================
+// Test Data Structures for Parameterized Tests
+// =============================================================================
 
-TEST_F(ScalarTypeTest, FloatEnumValue) {
-  // Verify Float has the correct enum value (6) to match PyTorch
-  EXPECT_EQ(static_cast<int>(ScalarType::Float), 6);
+struct ScalarTypeTestData {
+  ScalarType dtype;
+  int expected_enum_value;
+  size_t expected_element_size;
+  const char* expected_name;
+  bool is_floating;
+  bool is_integral;
+  bool is_integral_with_bool;
+  bool is_bool;
+};
+
+// All supported scalar types with their expected properties
+const std::vector<ScalarTypeTestData> kAllScalarTypes = {
+    // dtype, enum_value, element_size, name, is_float, is_int, is_int_w_bool,
+    // is_bool
+    {ScalarType::Char, 1, 1, "Char", false, true, true, false},
+    {ScalarType::Short, 2, 2, "Short", false, true, true, false},
+    {ScalarType::Int, 3, 4, "Int", false, true, true, false},
+    {ScalarType::Long, 4, 8, "Long", false, true, true, false},
+    {ScalarType::Float, 6, 4, "Float", true, false, false, false},
+    {ScalarType::Bool, 11, 1, "Bool", false, false, true, true},
+    {ScalarType::BFloat16, 15, 2, "BFloat16", true, false, false, false},
+};
+
+// =============================================================================
+// Parameterized Test Fixture
+// =============================================================================
+
+class ScalarTypeParamTest
+    : public ::testing::TestWithParam<ScalarTypeTestData> {};
+
+TEST_P(ScalarTypeParamTest, EnumValue) {
+  const auto& data = GetParam();
+  EXPECT_EQ(static_cast<int>(data.dtype), data.expected_enum_value)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, ElementSize) {
+  const auto& data = GetParam();
+  EXPECT_EQ(elementSize(data.dtype), data.expected_element_size)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, ToString) {
+  const auto& data = GetParam();
+  EXPECT_STREQ(toString(data.dtype), data.expected_name)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, IsFloatingType) {
+  const auto& data = GetParam();
+  EXPECT_EQ(isFloatingType(data.dtype), data.is_floating)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, IsIntegralTypeWithoutBool) {
+  const auto& data = GetParam();
+  EXPECT_EQ(isIntegralType(data.dtype, false), data.is_integral)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, IsIntegralTypeWithBool) {
+  const auto& data = GetParam();
+  EXPECT_EQ(isIntegralType(data.dtype, true), data.is_integral_with_bool)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, IsBoolType) {
+  const auto& data = GetParam();
+  EXPECT_EQ(isBoolType(data.dtype), data.is_bool)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+TEST_P(ScalarTypeParamTest, StreamOperator) {
+  const auto& data = GetParam();
+  std::ostringstream oss;
+  oss << data.dtype;
+  EXPECT_EQ(oss.str(), data.expected_name)
+      << "Failed for dtype: " << toString(data.dtype);
+}
+
+INSTANTIATE_TEST_SUITE_P(
+    AllTypes,
+    ScalarTypeParamTest,
+    ::testing::ValuesIn(kAllScalarTypes),
+    [](const ::testing::TestParamInfo<ScalarTypeTestData>& info) {
+      return std::string(info.param.expected_name);
+    });
+
+// =============================================================================
+// Type Constant Tests
+// =============================================================================
+
+class ScalarTypeConstantsTest : public ::testing::Test {};
+
+TEST_F(ScalarTypeConstantsTest, KCharConstant) {
+  EXPECT_EQ(kChar, ScalarType::Char);
+}
+
+TEST_F(ScalarTypeConstantsTest, KShortConstant) {
+  EXPECT_EQ(kShort, ScalarType::Short);
 }
 
-TEST_F(ScalarTypeTest, KFloatConstant) {
-  // Verify kFloat constant
+TEST_F(ScalarTypeConstantsTest, KIntConstant) {
+  EXPECT_EQ(kInt, ScalarType::Int);
+}
+
+TEST_F(ScalarTypeConstantsTest, KLongConstant) {
+  EXPECT_EQ(kLong, ScalarType::Long);
+}
+
+TEST_F(ScalarTypeConstantsTest, KFloatConstant) {
   EXPECT_EQ(kFloat, ScalarType::Float);
 }
 
-TEST_F(ScalarTypeTest, ElementSizeFloat) {
-  // Verify elementSize returns correct size for Float (4 bytes)
-  EXPECT_EQ(elementSize(ScalarType::Float), sizeof(float));
-  EXPECT_EQ(elementSize(ScalarType::Float), 4);
+TEST_F(ScalarTypeConstantsTest, KBoolConstant) {
+  EXPECT_EQ(kBool, ScalarType::Bool);
 }
 
-TEST_F(ScalarTypeTest, ToStringFloat) {
-  // Verify toString returns correct string for Float
-  EXPECT_STREQ(toString(ScalarType::Float), "Float");
+TEST_F(ScalarTypeConstantsTest, KBFloat16Constant) {
+  EXPECT_EQ(kBFloat16, ScalarType::BFloat16);
 }
 
-TEST_F(ScalarTypeTest, ToStringUndefined) {
-  // Verify toString returns correct string for Undefined
+// =============================================================================
+// Edge Cases and Special Values
+// =============================================================================
+
+class ScalarTypeEdgeCasesTest : public ::testing::Test {};
+
+TEST_F(ScalarTypeEdgeCasesTest, UndefinedToString) {
   EXPECT_STREQ(toString(ScalarType::Undefined), "Undefined");
 }
 
-TEST_F(ScalarTypeTest, IsFloatingType) {
-  // Verify isFloatingType works correctly
-  EXPECT_TRUE(isFloatingType(ScalarType::Float));
+TEST_F(ScalarTypeEdgeCasesTest, UndefinedIsNotFloating) {
+  EXPECT_FALSE(isFloatingType(ScalarType::Undefined));
 }
 
-TEST_F(ScalarTypeTest, IsIntegralType) {
-  // Verify isIntegralType works correctly
-  // Currently no integral types are supported, so Float should return false
-  EXPECT_FALSE(isIntegralType(ScalarType::Float, false));
-  EXPECT_FALSE(isIntegralType(ScalarType::Float, true));
+TEST_F(ScalarTypeEdgeCasesTest, UndefinedIsNotIntegral) {
+  EXPECT_FALSE(isIntegralType(ScalarType::Undefined, false));
+  EXPECT_FALSE(isIntegralType(ScalarType::Undefined, true));
 }
 
-TEST_F(ScalarTypeTest, StreamOperator) {
-  // Verify stream operator works
-  std::ostringstream oss;
-  oss << ScalarType::Float;
-  EXPECT_EQ(oss.str(), "Float");
+TEST_F(ScalarTypeEdgeCasesTest, UndefinedIsNotBool) {
+  EXPECT_FALSE(isBoolType(ScalarType::Undefined));
+}
+
+// =============================================================================
+// Element Size Consistency Tests
+// =============================================================================
+
+class ElementSizeConsistencyTest : public ::testing::Test {};
+
+TEST_F(ElementSizeConsistencyTest, CharMatchesSizeofInt8) {
+  EXPECT_EQ(elementSize(ScalarType::Char), sizeof(int8_t));
+}
+
+TEST_F(ElementSizeConsistencyTest, ShortMatchesSizeofInt16) {
+  EXPECT_EQ(elementSize(ScalarType::Short), sizeof(int16_t));
+}
+
+TEST_F(ElementSizeConsistencyTest, IntMatchesSizeofInt32) {
+  EXPECT_EQ(elementSize(ScalarType::Int), sizeof(int32_t));
+}
+
+TEST_F(ElementSizeConsistencyTest, LongMatchesSizeofInt64) {
+  EXPECT_EQ(elementSize(ScalarType::Long), sizeof(int64_t));
+}
+
+TEST_F(ElementSizeConsistencyTest, FloatMatchesSizeofFloat) {
+  EXPECT_EQ(elementSize(ScalarType::Float), sizeof(float));
+}
+
+TEST_F(ElementSizeConsistencyTest, BoolMatchesSizeofBool) {
+  EXPECT_EQ(elementSize(ScalarType::Bool), sizeof(bool));
+}
+
+TEST_F(ElementSizeConsistencyTest, BFloat16MatchesSizeofBFloat16) {
+  EXPECT_EQ(elementSize(ScalarType::BFloat16), sizeof(BFloat16));
 }

backends/aoti/slim/core/test/targets.bzl

@@ -34,3 +34,13 @@ def define_common_targets():
             "//executorch/backends/aoti/slim/core:storage",
         ],
     )
+
+    runtime.cxx_test(
+        name = "test_slimtensor_dtypes",
+        srcs = [
+            "test_slimtensor_dtypes.cpp",
+        ],
+        deps = [
+            "//executorch/backends/aoti/slim/factory:empty",
+        ],
+    )