[mlir][spirv] Do not truncate i/f64 -> i/f32 in SPIRVConversion

[kuhar]

Summary

This truncation can be unexpected and break program behavior.
Dedicated emulation passes should be used instead.

Also rename pass options to "emulate-lt-32-bit-scalar-types".

Fixes: https://github.com/llvm/llvm-project/issues/57917

[antiagainst]

mlir/test/Conversion/ArithToSPIRV/arith-to-spirv.mlir

1522

This is for 16 bit?

1567

This is for index and bool?

1868

This is for f16?

mlir/test/Conversion/FuncToSPIRV/types-to-spirv.mlir

48

This is for i8 and i16?

[kuhar]

mlir/test/Conversion/ArithToSPIRV/arith-to-spirv.mlir

1522

I tried to remove the related duplicated tests cases here and the remaining ones in https://reviews.llvm.org/D137166

Let me know if I removed too much by accident

1567

see above

1868

see above

mlir/test/Conversion/FuncToSPIRV/types-to-spirv.mlir

48

see above

[kuhar]

ping @antiagainst

[Hardcode84]

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

227

Can we get a separate option for this (set to False by default), instead of just disabling it?

[kuhar]

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

227

Do we have a use case for this? If yes, I can add a new option like .emulateGT32BitScalarTypes, but this will make testing more difficult

[Hardcode84]

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

227

It looked useful but I'm ok for it to be removed if it is too much problem to keep it around.,

Also, after the second look it seem it will produce plainly wrong code for memrefs passes to kernel from outside, as element size changes.

[antiagainst]

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

227

Yes. This is actually dangerous path, even behind an option. For cases where we really need larger bitwidth, the lowering would be just plainly wrong. So we'd like to remove it to avoid subtle bugs. For proper larger bitwidth emulation, Jakub has been builing a more proper and principled solution (you can search his recent commits); you can feel free to use that if needed.

mlir/test/Conversion/ArithToSPIRV/arith-to-spirv.mlir

1522

Verified yes this is duplicated.

1567

Verified yes this is duplicated.

1868

Verified yes this is duplicated.

mlir/test/Conversion/FuncToSPIRV/types-to-spirv.mlir

48

This one looks is not duplicated. So we should keep it.

[antiagainst]

LGTM, but please double check the test in types-to-spirv.mlir

[Hardcode84]

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

227

Just FYI, I was experimenting with proper f64 truncation passes in our project https://github.com/intel/mlir-extensions/pull/438

It probably can be pulled upstream after some fixes in memref dialect.

Thanks

[antiagainst]

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

227

Oh that's cool to know! Jakub's change just handles integers. FP is more tricky; thanks for working on that!

[kuhar]

Add accidentally deleted tests. Rebase.

mlir/include/mlir/Conversion/Passes.td

 // ArithToSPIRV
 //===----------------------------------------------------------------------===//
 
 def ConvertArithToSPIRV : Pass<"convert-arith-to-spirv"> {
   let summary = "Convert Arith dialect to SPIR-V dialect";
   let constructor = "mlir::arith::createConvertArithToSPIRVPass()";
   let dependentDialects = ["spirv::SPIRVDialect"];
   let options = [
-    Option<"emulateNon32BitScalarTypes", "emulate-non-32-bit-scalar-types",
+    Option<"emulateLT32BitScalarTypes", "emulate-lt-32-bit-scalar-types",
            "bool", /*default=*/"true",
-           "Emulate non-32-bit scalar types with 32-bit ones if "
-           "missing native support">,
+           "Emulate narrower scalar types with 32-bit ones if not supported by "
+           "the target">,
     Option<"enableFastMath", "enable-fast-math",
            "bool", /*default=*/"false",
            "Enable fast math mode (assuming no NaN and infinity for floating "
            "point values) when performing conversion">
   ];
 }
 
 //===----------------------------------------------------------------------===//

 // ControlFlowToSPIRV
 //===----------------------------------------------------------------------===//
 
 def ConvertControlFlowToSPIRV : Pass<"convert-cf-to-spirv"> {
   let summary = "Convert ControlFlow dialect to SPIR-V dialect";
   let constructor = "mlir::createConvertControlFlowToSPIRVPass()";
   let dependentDialects = ["spirv::SPIRVDialect"];
   let options = [
-    Option<"emulateNon32BitScalarTypes", "emulate-non-32-bit-scalar-types",
+    Option<"emulateLT32BitScalarTypes", "emulate-lt-32-bit-scalar-types",
            "bool", /*default=*/"true",
-           "Emulate non-32-bit scalar types with 32-bit ones if "
-           "missing native support">
+           "Emulate narrower scalar types with 32-bit ones if not supported by"
+           " the target">
   ];
 }
 
 //===----------------------------------------------------------------------===//
 // FuncToLLVM
 //===----------------------------------------------------------------------===//
 
 def ConvertFuncToLLVM : Pass<"convert-func-to-llvm", "ModuleOp"> {

 // FuncToSPIRV
 //===----------------------------------------------------------------------===//
 
 def ConvertFuncToSPIRV : Pass<"convert-func-to-spirv"> {
   let summary = "Convert Func dialect to SPIR-V dialect";
   let constructor = "mlir::createConvertFuncToSPIRVPass()";
   let dependentDialects = ["spirv::SPIRVDialect"];
   let options = [
-    Option<"emulateNon32BitScalarTypes", "emulate-non-32-bit-scalar-types",
+    Option<"emulateLT32BitScalarTypes", "emulate-lt-32-bit-scalar-types",
            "bool", /*default=*/"true",
-           "Emulate non-32-bit scalar types with 32-bit ones if "
-           "missing native support">
+           "Emulate narrower scalar types with 32-bit ones if not supported by"
+           " the target">
   ];
 }
 
 //===----------------------------------------------------------------------===//
 // GPUCommon
 //===----------------------------------------------------------------------===//
 
 def GpuToLLVMConversionPass : Pass<"gpu-to-llvm", "ModuleOp"> {

 // TensorToSPIRV
 //===----------------------------------------------------------------------===//
 
 def ConvertTensorToSPIRV : Pass<"convert-tensor-to-spirv"> {
   let summary = "Convert Tensor dialect to SPIR-V dialect";
   let constructor = "mlir::createConvertTensorToSPIRVPass()";
   let dependentDialects = ["spirv::SPIRVDialect"];
   let options = [
-    Option<"emulateNon32BitScalarTypes", "emulate-non-32-bit-scalar-types",
+    Option<"emulateLT32BitScalarTypes", "emulate-lt-32-bit-scalar-types",
            "bool", /*default=*/"true",
-           "Emulate non-32-bit scalar types with 32-bit ones if "
-           "missing native support">
+           "Emulate narrower scalar types with 32-bit ones if not supported by"
+           " the target">
   ];
 }
 
 //===----------------------------------------------------------------------===//
 // TosaToArith
 //===----------------------------------------------------------------------===//
 
 def TosaToArith : Pass<"tosa-to-arith"> {

mlir/include/mlir/Dialect/SPIRV/Transforms/SPIRVConversion.h

 //===----------------------------------------------------------------------===//
 // Type Converter
 //===----------------------------------------------------------------------===//
 
 struct SPIRVConversionOptions {
   /// The number of bits to store a boolean value.
   unsigned boolNumBits{8};
 
-  /// Whether to emulate non-32-bit scalar types with 32-bit scalar types if
-  /// no native support.
+  /// Whether to emulate narrower scalar types with 32-bit scalar types if not
+  /// supported by the target.
   ///
   /// Non-32-bit scalar types require special hardware support that may not
   /// exist on all GPUs. This is reflected in SPIR-V as that non-32-bit scalar
   /// types require special capabilities or extensions. This option controls
-  /// whether to use 32-bit types to emulate, if a scalar type of a certain
-  /// bitwidth is not supported in the target environment. This requires the
-  /// runtime to also feed in data with a matched bitwidth and layout for
-  /// interface types. The runtime can do that by inspecting the SPIR-V
-  /// module.
+  /// whether to use 32-bit types to emulate < 32-bits-wide scalars, if a scalar
+  /// type of a certain bitwidth is not supported in the target environment.
+  /// This requires the runtime to also feed in data with a matched bitwidth and
+  /// layout for interface types. The runtime can do that by inspecting the
+  /// SPIR-V module.
   ///
   /// If the original scalar type has less than 32-bit, a multiple of its
   /// values will be packed into one 32-bit value to be memory efficient.
-  bool emulateNon32BitScalarTypes{true};
+  bool emulateLT32BitScalarTypes{true};
 
   /// Use 64-bit integers to convert index types.
   bool use64bitIndex{false};
 
   /// Whether to enable fast math mode during conversion. If true, various
   /// patterns would assume no NaN/infinity numbers as inputs, and thus there
   /// will be no special guards emitted to check and handle such cases.
   bool enableFastMathMode{false};

mlir/lib/Conversion/ArithToSPIRV/ArithToSPIRV.cpp

 struct ConvertArithToSPIRVPass
     : public impl::ConvertArithToSPIRVBase<ConvertArithToSPIRVPass> {
   void runOnOperation() override {
     Operation *op = getOperation();
     auto targetAttr = spirv::lookupTargetEnvOrDefault(op);
     auto target = SPIRVConversionTarget::get(targetAttr);
 
     SPIRVConversionOptions options;
-    options.emulateNon32BitScalarTypes = this->emulateNon32BitScalarTypes;
+    options.emulateLT32BitScalarTypes = this->emulateLT32BitScalarTypes;
     options.enableFastMathMode = this->enableFastMath;
     SPIRVTypeConverter typeConverter(targetAttr, options);
 
     // Use UnrealizedConversionCast as the bridge so that we don't need to pull
     // in patterns for other dialects.
     auto addUnrealizedCast = [](OpBuilder &builder, Type type,
                                 ValueRange inputs, Location loc) {
       auto cast = builder.create<UnrealizedConversionCastOp>(loc, type, inputs);

mlir/lib/Conversion/ControlFlowToSPIRV/ControlFlowToSPIRVPass.cpp

void ConvertControlFlowToSPIRVPass::runOnOperation() {
   MLIRContext *context = &getContext();
   Operation *op = getOperation();
 
   auto targetAttr = spirv::lookupTargetEnvOrDefault(op);
   std::unique_ptr<ConversionTarget> target =
       SPIRVConversionTarget::get(targetAttr);
 
   SPIRVConversionOptions options;
-  options.emulateNon32BitScalarTypes = this->emulateNon32BitScalarTypes;
+  options.emulateLT32BitScalarTypes = this->emulateLT32BitScalarTypes;
   SPIRVTypeConverter typeConverter(targetAttr, options);
 
   RewritePatternSet patterns(context);
   cf::populateControlFlowToSPIRVPatterns(typeConverter, patterns);
 
   if (failed(applyPartialConversion(op, *target, std::move(patterns))))
     return signalPassFailure();
 }
 
 std::unique_ptr<OperationPass<>> mlir::createConvertControlFlowToSPIRVPass() {
   return std::make_unique<ConvertControlFlowToSPIRVPass>();
 }

mlir/lib/Conversion/FuncToSPIRV/FuncToSPIRVPass.cpp

void ConvertFuncToSPIRVPass::runOnOperation() {
   MLIRContext *context = &getContext();
   Operation *op = getOperation();
 
   auto targetAttr = spirv::lookupTargetEnvOrDefault(op);
   std::unique_ptr<ConversionTarget> target =
       SPIRVConversionTarget::get(targetAttr);
 
   SPIRVConversionOptions options;
-  options.emulateNon32BitScalarTypes = this->emulateNon32BitScalarTypes;
+  options.emulateLT32BitScalarTypes = this->emulateLT32BitScalarTypes;
   SPIRVTypeConverter typeConverter(targetAttr, options);
 
   RewritePatternSet patterns(context);
   populateFuncToSPIRVPatterns(typeConverter, patterns);
   populateBuiltinFuncToSPIRVPatterns(typeConverter, patterns);
 
   if (failed(applyPartialConversion(op, *target, std::move(patterns))))
     return signalPassFailure();
 }
 
 std::unique_ptr<OperationPass<>> mlir::createConvertFuncToSPIRVPass() {
   return std::make_unique<ConvertFuncToSPIRVPass>();
 }

mlir/lib/Conversion/TensorToSPIRV/TensorToSPIRVPass.cpp

void runOnOperation() override {
     MLIRContext *context = &getContext();
     Operation *op = getOperation();
 
     auto targetAttr = spirv::lookupTargetEnvOrDefault(op);
     std::unique_ptr<ConversionTarget> target =
         SPIRVConversionTarget::get(targetAttr);
 
     SPIRVConversionOptions options;
-    options.emulateNon32BitScalarTypes = this->emulateNon32BitScalarTypes;
+    options.emulateLT32BitScalarTypes = this->emulateLT32BitScalarTypes;
     SPIRVTypeConverter typeConverter(targetAttr, options);
 
     RewritePatternSet patterns(context);
     arith::populateArithToSPIRVPatterns(typeConverter, patterns);
     populateFuncToSPIRVPatterns(typeConverter, patterns);
     populateTensorToSPIRVPatterns(typeConverter, /*byteCountThreshold=*/64,
                                   patterns);
     populateBuiltinFuncToSPIRVPatterns(typeConverter, patterns);

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

static Type convertScalarType(const spirv::TargetEnv &targetEnv,
 
   // If all requirements are met, then we can accept this type as-is.
   if (succeeded(checkCapabilityRequirements(type, targetEnv, capabilities)) &&
       succeeded(checkExtensionRequirements(type, targetEnv, extensions)))
     return type;
 
   // Otherwise we need to adjust the type, which really means adjusting the
   // bitwidth given this is a scalar type.
+  if (!options.emulateLT32BitScalarTypes)
+    return nullptr;
 
-  if (!options.emulateNon32BitScalarTypes)
+  // We only emulate narrower scalar types here and do not truncate results.
+  if (type.getIntOrFloatBitWidth() > 32) {
+    LLVM_DEBUG(llvm::dbgs()
+               << type
+               << " not converted to 32-bit for SPIR-V to avoid truncation\n");
     return nullptr;
+  }
 
   if (auto floatType = type.dyn_cast<FloatType>()) {
     LLVM_DEBUG(llvm::dbgs() << type << " converted to 32-bit for SPIR-V\n");
     return Builder(targetEnv.getContext()).getF32Type();
   }
 
   auto intType = type.cast<IntegerType>();
   LLVM_DEBUG(llvm::dbgs() << type << " converted to 32-bit for SPIR-V\n");

mlir/test/Conversion/ArithToSPIRV/arith-to-spirv-unsupported.mlir

 }
 
 ///===----------------------------------------------------------------------===//
 // Constant ops
 //===----------------------------------------------------------------------===//
 
 // -----
 
-func.func @unsupported_constant_0() {
+func.func @unsupported_constant_i64_0() {
+  // expected-error @+1 {{failed to legalize operation 'arith.constant'}}
+  %0 = arith.constant 0 : i64
+  return
+}
+
+// -----
+
+func.func @unsupported_constant_i64_1() {
   // expected-error @+1 {{failed to legalize operation 'arith.constant'}}
   %0 = arith.constant 4294967296 : i64 // 2^32
   return
 }
 
 // -----
 
-func.func @unsupported_constant_1() {
+func.func @unsupported_constant_vector_2xi64_0() {
+  // expected-error @+1 {{failed to legalize operation 'arith.constant'}}
+  %1 = arith.constant dense<0> : vector<2xi64>
+  return
+}
+
+// -----
+
+func.func @unsupported_constant_f64_0() {
   // expected-error @+1 {{failed to legalize operation 'arith.constant'}}
-  %1 = arith.constant -2147483649 : i64 // -2^31 - 1
+  %1 = arith.constant 0.0 : f64
   return
 }
 
 // -----
 
-func.func @unsupported_constant_2() {
+func.func @unsupported_constant_vector_2xf64_0() {
   // expected-error @+1 {{failed to legalize operation 'arith.constant'}}
-  %2 = arith.constant -2147483649 : i64 // -2^31 - 1
+  %1 = arith.constant dense<0.0> : vector<2xf64>
   return
 }
+
+// -----
+
+func.func @unsupported_constant_tensor_2xf64_0() {
+  // expected-error @+1 {{failed to legalize operation 'arith.constant'}}
+  %1 = arith.constant dense<0.0> : tensor<2xf64>
+  return
+}
+
+///===----------------------------------------------------------------------===//
+// Type emulation
+//===----------------------------------------------------------------------===//
+
+// -----
+
+module attributes {
+  spirv.target_env = #spirv.target_env<
+    #spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
+} {
+
+// Check that we do not emualte i64 by truncating to i32.
+func.func @unsupported_i64(%arg0: i64) {
+  // expected-error@+1 {{failed to legalize operation 'arith.addi'}}
+  %2 = arith.addi %arg0, %arg0: i64
+  return
+}
+
+} // end module
+
+// -----
+
+module attributes {
+  spirv.target_env = #spirv.target_env<
+    #spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
+} {
+
+// Check that we do not emualte f64 by truncating to i32.
+func.func @unsupported_f64(%arg0: f64) {
+  // expected-error@+1 {{failed to legalize operation 'arith.addf'}}
+  %2 = arith.addf %arg0, %arg0: f64
+  return
+}
+
+} // end module

mlir/test/Conversion/ArithToSPIRV/arith-to-spirv.mlir

func.func @constant_size1() {
   %2 = arith.constant dense<5.0> : tensor<1xf64>
   return
 }
 
 } // end module
 
 // -----
 
-// Check that constants are converted to 32-bit when no special capability.
+// Check that constants are widened to 32-bit when no special capability.
 module attributes {
   spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
 } {
 
 // CHECK-LABEL: @constant_16bit
 func.func @constant_16bit() {
   // CHECK: spirv.Constant 4 : i32
   %0 = arith.constant 4 : i16
   // CHECK: spirv.Constant 5.000000e+00 : f32
   %1 = arith.constant 5.0 : f16
   // CHECK: spirv.Constant dense<[2, 3]> : vector<2xi32>
   %2 = arith.constant dense<[2, 3]> : vector<2xi16>
   // CHECK: spirv.Constant dense<4.000000e+00> : tensor<5xf32> : !spirv.array<5 x f32>
   %3 = arith.constant dense<4.0> : tensor<5xf16>
   // CHECK: spirv.Constant dense<[1.000000e+00, 2.000000e+00, 3.000000e+00, 4.000000e+00]> : tensor<4xf32> : !spirv.array<4 x f32>
   %4 = arith.constant dense<[[1.0, 2.0], [3.0, 4.0]]> : tensor<2x2xf16>
   return
 }
 
-// CHECK-LABEL: @constant_64bit
-func.func @constant_64bit() {
-  // CHECK: spirv.Constant 4 : i32
-  %0 = arith.constant 4 : i64
-  // CHECK: spirv.Constant 5.000000e+00 : f32
-  %1 = arith.constant 5.0 : f64
-  // CHECK: spirv.Constant dense<[2, 3]> : vector<2xi32>
-  %2 = arith.constant dense<[2, 3]> : vector<2xi64>
-  // CHECK: spirv.Constant dense<4.000000e+00> : tensor<5xf32> : !spirv.array<5 x f32>
-  %3 = arith.constant dense<4.0> : tensor<5xf64>
-  // CHECK: spirv.Constant dense<[1.000000e+00, 2.000000e+00, 3.000000e+00, 4.000000e+00]> : tensor<4xf32> : !spirv.array<4 x f32>
-  %4 = arith.constant dense<[[1.0, 2.0], [3.0, 4.0]]> : tensor<2x2xf16>
-  return
-}
-
 // CHECK-LABEL: @constant_size1
 func.func @constant_size1() {
   // CHECK: spirv.Constant 4 : i32
-  %0 = arith.constant dense<4> : vector<1xi64>
+  %0 = arith.constant dense<4> : vector<1xi16>
   // CHECK: spirv.Constant 5.000000e+00 : f32
-  %1 = arith.constant dense<5.0> : tensor<1xf64>
+  %1 = arith.constant dense<5.0> : tensor<1xf16>
   return
 }
 
 // CHECK-LABEL: @corner_cases
 func.func @corner_cases() {
-  // CHECK: %{{.*}} = spirv.Constant -1 : i32
-  %0 = arith.constant 4294967295  : i64 // 2^32 - 1
-  // CHECK: %{{.*}} = spirv.Constant 2147483647 : i32
-  %1 = arith.constant 2147483647  : i64 // 2^31 - 1
-  // CHECK: %{{.*}} = spirv.Constant -2147483648 : i32
-  %2 = arith.constant 2147483648  : i64 // 2^31
-  // CHECK: %{{.*}} = spirv.Constant -2147483648 : i32
-  %3 = arith.constant -2147483648 : i64 // -2^31
-
-  // CHECK: %{{.*}} = spirv.Constant -1 : i32
-  %5 = arith.constant -1 : i64
+  %5 = arith.constant -1 : i16
   // CHECK: %{{.*}} = spirv.Constant -2 : i32
-  %6 = arith.constant -2 : i64
+  %6 = arith.constant -2 : i16
   // CHECK: %{{.*}} = spirv.Constant -1 : i32
   %7 = arith.constant -1 : index
   // CHECK: %{{.*}} = spirv.Constant -2 : i32
   %8 = arith.constant -2 : index
 
-
   // CHECK: spirv.Constant false
   %9 = arith.constant false
   // CHECK: spirv.Constant true
   %10 = arith.constant true
 
   return
 }
 

 
 // Checks that cast types will be adjusted when missing special capabilities for
 // certain non-32-bit scalar types.
 module attributes {
   spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [Float16], []>, #spirv.resource_limits<>>
 } {
 
 // CHECK-LABEL: @fptrunc1
-// CHECK-SAME: %[[A:.*]]: f64
-func.func @fptrunc1(%arg0 : f64) -> f16 {
-  // CHECK: %[[ARG:.+]] = builtin.unrealized_conversion_cast %[[A]] : f64 to f32
-  // CHECK-NEXT: spirv.FConvert %[[ARG]] : f32 to f16
-  %0 = arith.truncf %arg0 : f64 to f16
-  return %0: f16
-}
-
-// CHECK-LABEL: @fptrunc2
 // CHECK-SAME: %[[ARG:.*]]: f32
-func.func @fptrunc2(%arg0: f32) -> f16 {
+func.func @fptrunc1(%arg0: f32) -> f16 {
   // CHECK-NEXT: spirv.FConvert %[[ARG]] : f32 to f16
   %0 = arith.truncf %arg0 : f32 to f16
   return %0: f16
 }
 
-// CHECK-LABEL: @sitofp
-func.func @sitofp(%arg0 : i64) -> f64 {
-  // CHECK: spirv.ConvertSToF %{{.*}} : i32 to f32
-  %0 = arith.sitofp %arg0 : i64 to f64
-  return %0: f64
-}
-
 } // end module
 
 // -----
 
 // Check various lowerings for OpenCL.
 module attributes {
   spirv.target_env = #spirv.target_env<
     #spirv.vce<v1.0, [Int16, Kernel], []>, #spirv.resource_limits<>>
func.func @int_vector23(%arg0: vector<2xi8>, %arg1: vector<3xi16>) {
   // CHECK: spirv.SDiv %{{.*}}, %{{.*}}: vector<2xi32>
   %0 = arith.divsi %arg0, %arg0: vector<2xi8>
   // CHECK: spirv.SDiv %{{.*}}, %{{.*}}: vector<3xi32>
   %1 = arith.divsi %arg1, %arg1: vector<3xi16>
   return
 }
 
 // CHECK-LABEL: @float_scalar
-func.func @float_scalar(%arg0: f16, %arg1: f64) {
+func.func @float_scalar(%arg0: f16) {
   // CHECK: spirv.FAdd %{{.*}}, %{{.*}}: f32
   %0 = arith.addf %arg0, %arg0: f16
-  // CHECK: spirv.FMul %{{.*}}, %{{.*}}: f32
-  %1 = arith.mulf %arg1, %arg1: f64
   return
 }
 
 } // end module
 
 // -----
 
 //===----------------------------------------------------------------------===//
func.func @constant_64bit() {
   %3 = arith.constant dense<4.0> : tensor<5xf64>
   return
 }
 
 } // end module
 
 // -----
 
-// Check that constants are converted to 32-bit when no special capability.
-module attributes {
-  spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
-} {
-
-// CHECK-LABEL: @constant_16bit
-func.func @constant_16bit() {
-  // CHECK: spirv.Constant 4 : i32
-  %0 = arith.constant 4 : i16
-  // CHECK: spirv.Constant 5.000000e+00 : f32
-  %1 = arith.constant 5.0 : f16
-  // CHECK: spirv.Constant dense<[2, 3]> : vector<2xi32>
-  %2 = arith.constant dense<[2, 3]> : vector<2xi16>
-  // CHECK: spirv.Constant dense<4.000000e+00> : tensor<5xf32> : !spirv.array<5 x f32>
-  %3 = arith.constant dense<4.0> : tensor<5xf16>
-  // CHECK: spirv.Constant dense<[1.000000e+00, 2.000000e+00, 3.000000e+00, 4.000000e+00]> : tensor<4xf32> : !spirv.array<4 x f32>
-  %4 = arith.constant dense<[[1.0, 2.0], [3.0, 4.0]]> : tensor<2x2xf16>
-  return
-}
-
-// CHECK-LABEL: @constant_64bit
-func.func @constant_64bit() {
-  // CHECK: spirv.Constant 4 : i32
-  %0 = arith.constant 4 : i64
-  // CHECK: spirv.Constant 5.000000e+00 : f32
-  %1 = arith.constant 5.0 : f64
-  // CHECK: spirv.Constant dense<[2, 3]> : vector<2xi32>
-  %2 = arith.constant dense<[2, 3]> : vector<2xi64>
-  // CHECK: spirv.Constant dense<4.000000e+00> : tensor<5xf32> : !spirv.array<5 x f32>
-  %3 = arith.constant dense<4.0> : tensor<5xf64>
-  // CHECK: spirv.Constant dense<[1.000000e+00, 2.000000e+00, 3.000000e+00, 4.000000e+00]> : tensor<4xf32> : !spirv.array<4 x f32>
-  %4 = arith.constant dense<[[1.0, 2.0], [3.0, 4.0]]> : tensor<2x2xf16>
-  return
-}
-
-// CHECK-LABEL: @corner_cases
-func.func @corner_cases() {
-  // CHECK: %{{.*}} = spirv.Constant -1 : i32
-  %0 = arith.constant 4294967295  : i64 // 2^32 - 1
-  // CHECK: %{{.*}} = spirv.Constant 2147483647 : i32
-  %1 = arith.constant 2147483647  : i64 // 2^31 - 1
-  // CHECK: %{{.*}} = spirv.Constant -2147483648 : i32
-  %2 = arith.constant 2147483648  : i64 // 2^31
-  // CHECK: %{{.*}} = spirv.Constant -2147483648 : i32
-  %3 = arith.constant -2147483648 : i64 // -2^31
-
-  // CHECK: %{{.*}} = spirv.Constant -1 : i32
-  %5 = arith.constant -1 : i64
-  // CHECK: %{{.*}} = spirv.Constant -2 : i32
-  %6 = arith.constant -2 : i64
-  // CHECK: %{{.*}} = spirv.Constant -1 : i32
-  %7 = arith.constant -1 : index
-  // CHECK: %{{.*}} = spirv.Constant -2 : i32
-  %8 = arith.constant -2 : index
-
-
-  // CHECK: spirv.Constant false
-  %9 = arith.constant false
-  // CHECK: spirv.Constant true
-  %10 = arith.constant true
-
-  return
-}
-
-} // end module
-
-// -----
-
 //===----------------------------------------------------------------------===//
 // std cast ops
 //===----------------------------------------------------------------------===//
 
 module attributes {
   spirv.target_env = #spirv.target_env<
     #spirv.vce<v1.0, [Int8, Int16, Int64, Float16, Float64], []>, #spirv.resource_limits<>>
 } {

 // CHECK-SAME: %[[ARG:.*]]: f32
 func.func @fpext2(%arg0 : f32) -> f64 {
   // CHECK-NEXT: spirv.FConvert %[[ARG]] : f32 to f64
   %0 = arith.extf %arg0 : f32 to f64
   return %0: f64
 }
 
 } // end module
-
-// -----
-
-// Checks that cast types will be adjusted when missing special capabilities for
-// certain non-32-bit scalar types.
-module attributes {
-  spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [Float16], []>, #spirv.resource_limits<>>
-} {
-
-// CHECK-LABEL: @fptrunc1
-// CHECK-SAME: %[[A:.*]]: f64
-func.func @fptrunc1(%arg0 : f64) -> f16 {
-  // CHECK: %[[ARG:.+]] = builtin.unrealized_conversion_cast %[[A]] : f64 to f32
-  // CHECK-NEXT: spirv.FConvert %[[ARG]] : f32 to f16
-  %0 = arith.truncf %arg0 : f64 to f16
-  return %0: f16
-}
-
-// CHECK-LABEL: @fptrunc2
-// CHECK-SAME: %[[ARG:.*]]: f32
-func.func @fptrunc2(%arg0: f32) -> f16 {
-  // CHECK-NEXT: spirv.FConvert %[[ARG]] : f32 to f16
-  %0 = arith.truncf %arg0 : f32 to f16
-  return %0: f16
-}
-
-// CHECK-LABEL: @sitofp
-func.func @sitofp(%arg0 : i64) -> f64 {
-  // CHECK: spirv.ConvertSToF %{{.*}} : i32 to f32
-  %0 = arith.sitofp %arg0 : i64 to f64
-  return %0: f64
-}
-
-} // end module
-
-// -----

mlir/test/Conversion/FuncToSPIRV/types-to-spirv.mlir

 // RUN: mlir-opt -split-input-file -convert-func-to-spirv %s -o - | FileCheck %s
-// RUN: mlir-opt -split-input-file -convert-func-to-spirv="emulate-non-32-bit-scalar-types=false" %s -o - | FileCheck %s --check-prefix=NOEMU
+// RUN: mlir-opt -split-input-file -convert-func-to-spirv="emulate-lt-32-bit-scalar-types=false" %s | \
+// RUN:   FileCheck %s --check-prefix=NOEMU
 
 //===----------------------------------------------------------------------===//
 // Integer types
 //===----------------------------------------------------------------------===//
 
 // Check that non-32-bit integer types are converted to 32-bit types if the
 // corresponding capabilities are not available.
 module attributes {
   spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
 } {
 
 // CHECK-LABEL: spirv.func @integer8
 // CHECK-SAME: i32
 // CHECK-SAME: si32
 // CHECK-SAME: ui32
-// NOEMU-LABEL: func @integer8
+// NOEMU-LABEL: func.func @integer8
 // NOEMU-SAME: i8
 // NOEMU-SAME: si8
 // NOEMU-SAME: ui8
 func.func @integer8(%arg0: i8, %arg1: si8, %arg2: ui8) { return }
 
 // CHECK-LABEL: spirv.func @integer16
 // CHECK-SAME: i32
 // CHECK-SAME: si32
 // CHECK-SAME: ui32
-// NOEMU-LABEL: func @integer16
+// NOEMU-LABEL: func.func @integer16
 // NOEMU-SAME: i16
 // NOEMU-SAME: si16
 // NOEMU-SAME: ui16
 func.func @integer16(%arg0: i16, %arg1: si16, %arg2: ui16) { return }
 
-// CHECK-LABEL: spirv.func @integer64
-// CHECK-SAME: i32
-// CHECK-SAME: si32
-// CHECK-SAME: ui32
-// NOEMU-LABEL: func @integer64
-// NOEMU-SAME: i64
-// NOEMU-SAME: si64
-// NOEMU-SAME: ui64
-func.func @integer64(%arg0: i64, %arg1: si64, %arg2: ui64) { return }
-
-} // end module
-
-// -----
-
-// Check that non-32-bit integer types are kept untouched if the corresponding
-// capabilities are available.
-module attributes {
-  spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [Int8, Int16, Int64], []>, #spirv.resource_limits<>>
-} {
-
-// CHECK-LABEL: spirv.func @integer8
-// CHECK-SAME: i8
-// CHECK-SAME: si8
-// CHECK-SAME: ui8
-// NOEMU-LABEL: spirv.func @integer8
-// NOEMU-SAME: i8
-// NOEMU-SAME: si8
-// NOEMU-SAME: ui8
-func.func @integer8(%arg0: i8, %arg1: si8, %arg2: ui8) { return }
-
-// CHECK-LABEL: spirv.func @integer16
-// CHECK-SAME: i16
-// CHECK-SAME: si16
-// CHECK-SAME: ui16
-// NOEMU-LABEL: spirv.func @integer16
-// NOEMU-SAME: i16
-// NOEMU-SAME: si16
-// NOEMU-SAME: ui16
-func.func @integer16(%arg0: i16, %arg1: si16, %arg2: ui16) { return }
-
-// CHECK-LABEL: spirv.func @integer64
+// We do not truncate 64-bit types to 32-bit ones.
+// CHECK-LABEL: func.func @integer64
 // CHECK-SAME: i64
 // CHECK-SAME: si64
 // CHECK-SAME: ui64
-// NOEMU-LABEL: spirv.func @integer64
+// NOEMU-LABEL: func @integer64
 // NOEMU-SAME: i64
 // NOEMU-SAME: si64
 // NOEMU-SAME: ui64
 func.func @integer64(%arg0: i64, %arg1: si64, %arg2: ui64) { return }
 
 } // end module
 
 // -----

 // Check that non-32-bit float types are converted to 32-bit types if the
 // corresponding capabilities are not available.
 module attributes {
   spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
 } {
 
 // CHECK-LABEL: spirv.func @float16
 // CHECK-SAME: f32
-// NOEMU-LABEL: func @float16
+// NOEMU-LABEL: func.func @float16
 // NOEMU-SAME: f16
 func.func @float16(%arg0: f16) { return }
 
-// CHECK-LABEL: spirv.func @float64
-// CHECK-SAME: f32
-// NOEMU-LABEL: func @float64
+// CHECK-LABEL: func.func @float64
+// CHECK-SAME: f64
+// NOEMU-LABEL: func.func @float64
 // NOEMU-SAME: f64
 func.func @float64(%arg0: f64) { return }
 
 } // end module
 
 // -----
 
 // Check that non-32-bit float types are kept untouched if the corresponding

 
 // -----
 
 //===----------------------------------------------------------------------===//
 // Vector types
 //===----------------------------------------------------------------------===//
 
 // Check that capabilities for scalar types affects vector types too: no special
-// capabilities available means using turning element types to 32-bit.
+// capabilities available means widening element types to 32-bit.
 module attributes {
   spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
 } {
 
 // CHECK-LABEL: spirv.func @int_vector
 // CHECK-SAME: vector<2xi32>
 // CHECK-SAME: vector<3xsi32>
-// CHECK-SAME: vector<4xui32>
 func.func @int_vector(
   %arg0: vector<2xi8>,
-  %arg1: vector<3xsi16>,
-  %arg2: vector<4xui64>
+  %arg1: vector<3xsi16>
 ) { return }
 
 // CHECK-LABEL: spirv.func @float_vector
 // CHECK-SAME: vector<2xf32>
-// CHECK-SAME: vector<3xf32>
 func.func @float_vector(
-  %arg0: vector<2xf16>,
-  %arg1: vector<3xf64>
+  %arg0: vector<2xf16>
 ) { return }
 
 // CHECK-LABEL: spirv.func @one_element_vector
 // CHECK-SAME: %{{.+}}: i32
 func.func @one_element_vector(%arg0: vector<1xi8>) { return }
 
 } // end module
 

 func.func @memref_16bit_Input(%arg3: memref<16xf16, #spirv.storage_class<Input>>) { return }
 
 // CHECK-LABEL: spirv.func @memref_16bit_Output
 // CHECK-SAME: !spirv.ptr<!spirv.struct<(!spirv.array<8 x f32>)>, Output>
 // NOEMU-LABEL: func @memref_16bit_Output
 // NOEMU-SAME: memref<16xf16, #spirv.storage_class<Output>>
 func.func @memref_16bit_Output(%arg4: memref<16xf16, #spirv.storage_class<Output>>) { return }
 
-// CHECK-LABEL: spirv.func @memref_64bit_StorageBuffer
-// CHECK-SAME: !spirv.ptr<!spirv.struct<(!spirv.array<32 x i32, stride=4> [0])>, StorageBuffer>
-// NOEMU-LABEL: func @memref_64bit_StorageBuffer
+// We do not truncate i64 to i32.
+
+// CHECK-LABEL: func.func @memref_64bit_StorageBuffer
+// CHECK-SAME: memref<16xi64, #spirv.storage_class<StorageBuffer>>
+// NOEMU-LABEL: func.func @memref_64bit_StorageBuffer
 // NOEMU-SAME: memref<16xi64, #spirv.storage_class<StorageBuffer>>
 func.func @memref_64bit_StorageBuffer(%arg0: memref<16xi64, #spirv.storage_class<StorageBuffer>>) { return }
 
-// CHECK-LABEL: spirv.func @memref_64bit_Uniform
-// CHECK-SAME: !spirv.ptr<!spirv.struct<(!spirv.array<32 x si32, stride=4> [0])>, Uniform>
-// NOEMU-LABEL: func @memref_64bit_Uniform
+// CHECK-LABEL: func.func @memref_64bit_Uniform
+// CHECK-SAME: memref<16xsi64, #spirv.storage_class<Uniform>>
+// NOEMU-LABEL: func.func @memref_64bit_Uniform
 // NOEMU-SAME: memref<16xsi64, #spirv.storage_class<Uniform>>
 func.func @memref_64bit_Uniform(%arg0: memref<16xsi64, #spirv.storage_class<Uniform>>) { return }
 
-// CHECK-LABEL: spirv.func @memref_64bit_PushConstant
-// CHECK-SAME: !spirv.ptr<!spirv.struct<(!spirv.array<32 x ui32, stride=4> [0])>, PushConstant>
-// NOEMU-LABEL: func @memref_64bit_PushConstant
+// CHECK-LABEL: func.func @memref_64bit_PushConstant
+// CHECK-SAME: memref<16xui64, #spirv.storage_class<PushConstant>>
+// NOEMU-LABEL: func.func @memref_64bit_PushConstant
 // NOEMU-SAME: memref<16xui64, #spirv.storage_class<PushConstant>>
 func.func @memref_64bit_PushConstant(%arg0: memref<16xui64, #spirv.storage_class<PushConstant>>) { return }
 
-// CHECK-LABEL: spirv.func @memref_64bit_Input
-// CHECK-SAME: !spirv.ptr<!spirv.struct<(!spirv.array<32 x f32>)>, Input>
-// NOEMU-LABEL: func @memref_64bit_Input
+// CHECK-LABEL: func.func @memref_64bit_Input
+// CHECK-SAME: memref<16xf64, #spirv.storage_class<Input>>
+// NOEMU-LABEL: func.func @memref_64bit_Input
 // NOEMU-SAME: memref<16xf64, #spirv.storage_class<Input>>
 func.func @memref_64bit_Input(%arg3: memref<16xf64, #spirv.storage_class<Input>>) { return }
 
-// CHECK-LABEL: spirv.func @memref_64bit_Output
-// CHECK-SAME: !spirv.ptr<!spirv.struct<(!spirv.array<32 x f32>)>, Output>
-// NOEMU-LABEL: func @memref_64bit_Output
+// CHECK-LABEL: func.func @memref_64bit_Output
+// CHECK-SAME: memref<16xf64, #spirv.storage_class<Output>>
+// NOEMU-LABEL: func.func @memref_64bit_Output
 // NOEMU-SAME: memref<16xf64, #spirv.storage_class<Output>>
 func.func @memref_64bit_Output(%arg4: memref<16xf64, #spirv.storage_class<Output>>) { return }
 
 } // end module
 
 // -----
 
 // Check that using non-32-bit scalar types in interface storage classes

 module attributes {
   spirv.target_env = #spirv.target_env<#spirv.vce<v1.0, [], []>, #spirv.resource_limits<>>
 } {
 
 // CHECK-LABEL: spirv.func @int_tensor_types
 // CHECK-SAME: !spirv.array<32 x i32>
 // CHECK-SAME: !spirv.array<32 x i32>
 // CHECK-SAME: !spirv.array<32 x i32>
-// CHECK-SAME: !spirv.array<32 x i32>
 func.func @int_tensor_types(
-  %arg0: tensor<8x4xi64>,
   %arg1: tensor<8x4xi32>,
   %arg2: tensor<8x4xi16>,
   %arg3: tensor<8x4xi8>
 ) { return }
 
 // CHECK-LABEL: spirv.func @float_tensor_types
 // CHECK-SAME: !spirv.array<32 x f32>
 // CHECK-SAME: !spirv.array<32 x f32>
-// CHECK-SAME: !spirv.array<32 x f32>
 func.func @float_tensor_types(
-  %arg0: tensor<8x4xf64>,
   %arg1: tensor<8x4xf32>,
   %arg2: tensor<8x4xf16>
 ) { return }
 
 } // end module
 
 // -----