[mlir][spirv] Fix int type declaration duplication when serializing (#143108)

At the MLIR level unsigned integer and signless integers are different
types. Indeed when looking up the two types in type definition cache
they do not match.

Hence when translating a SPIR-V module which contains both usign and
signless integers will contain the same type declaration twice
(something like OpTypeInt 32 0) which is not permitted in SPIR-V and
such generated modules fail validation.

This patch solves the problem by mapping unisgned integer types to
singless integer types before looking up in the type definition cache.

---------

Signed-off-by: Davide Grohmann <[email protected]>

Author: davidegrohmann

mlir/lib/Target/SPIRV/Serialization/Serializer.cpp

@@ -446,6 +446,19 @@ LogicalResult Serializer::processType(Location loc, Type type,
 LogicalResult
 Serializer::processTypeImpl(Location loc, Type type, uint32_t &typeID,
                             SetVector<StringRef> &serializationCtx) {
+
+  // Map unsigned integer types to singless integer types.
+  // This is needed otherwise the generated spirv assembly will contain
+  // twice a type declaration (like OpTypeInt 32 0) which is no permitted and
+  // such module fails validation. Indeed at MLIR level the two types are
+  // different and lookup in the cache below misses.
+  // Note: This conversion needs to happen here before the type is looked up in
+  // the cache.
+  if (type.isUnsignedInteger()) {
+    type = IntegerType::get(loc->getContext(), type.getIntOrFloatBitWidth(),
+                            IntegerType::SignednessSemantics::Signless);
+  }
+
   typeID = getTypeID(type);
   if (typeID)
     return success();

mlir/test/CMakeLists.txt

@@ -68,6 +68,7 @@ endif()
 llvm_canonicalize_cmake_booleans(
   LLVM_BUILD_EXAMPLES
   LLVM_HAS_NVPTX_TARGET
+  LLVM_INCLUDE_SPIRV_TOOLS_TESTS
   MLIR_ENABLE_BINDINGS_PYTHON
   MLIR_ENABLE_CUDA_RUNNER
   MLIR_ENABLE_ROCM_CONVERSIONS
@@ -217,6 +218,11 @@ if(MLIR_ENABLE_BINDINGS_PYTHON)
   )
 endif()
 
+if (LLVM_INCLUDE_SPIRV_TOOLS_TESTS)
+  list(APPEND MLIR_TEST_DEPENDS spirv-as)
+  list(APPEND MLIR_TEST_DEPENDS spirv-val)
+endif()
+
 # This target can be used to just build the dependencies
 # for the check-mlir target without executing the tests.
 # This is useful for bots when splitting the build step

mlir/test/Target/SPIRV/constant.mlir

@@ -1,6 +1,7 @@
 // RUN: mlir-translate --no-implicit-module --test-spirv-roundtrip %s | FileCheck %s
+// RUN: %if spirv-tools %{ mlir-translate -no-implicit-module -serialize-spirv %s | spirv-val %}
 
-spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
+spirv.module Logical Vulkan requires #spirv.vce<v1.3, [VulkanMemoryModel, Shader, Int64, Int16, Int8, Float64, Float16, CooperativeMatrixKHR], [SPV_KHR_vulkan_memory_model, SPV_KHR_cooperative_matrix]> {
   // CHECK-LABEL: @bool_const
   spirv.func @bool_const() -> () "None" {
     // CHECK: spirv.Constant true
@@ -305,4 +306,6 @@ spirv.module Logical GLSL450 requires #spirv.vce<v1.0, [Shader], []> {
     %coop = spirv.Constant dense<4> : !spirv.coopmatrix<16x16xi8, Subgroup, MatrixAcc>
     spirv.ReturnValue %coop : !spirv.coopmatrix<16x16xi8, Subgroup, MatrixAcc>
   }
+
+  spirv.EntryPoint "GLCompute" @bool_const
 }

mlir/test/lit.cfg.py

@@ -332,6 +332,7 @@ def find_real_python_interpreter():
 else:
     config.available_features.add("noasserts")
 
+config.targets = frozenset(config.targets_to_build.split())
 
 def have_host_jit_feature_support(feature_name):
     mlir_runner_exe = lit.util.which("mlir-runner", config.mlir_tools_dir)

mlir/test/lit.local.cfg

@@ -0,0 +1,7 @@
+if not "SPIRV" in config.root.targets:
+    config.unsupported = True
+
+if config.spirv_tools_tests:
+    config.available_features.add("spirv-tools")
+    config.substitutions.append(("spirv-as", os.path.join(config.llvm_tools_dir, "spirv-as")))
+    config.substitutions.append(("spirv-val", os.path.join(config.llvm_tools_dir, "spirv-val")))

mlir/test/lit.site.cfg.py.in

@@ -5,6 +5,8 @@ import sys
 config.target_triple = "@LLVM_TARGET_TRIPLE@"
 config.llvm_src_root = "@LLVM_SOURCE_DIR@"
 config.llvm_tools_dir = lit_config.substitute("@LLVM_TOOLS_DIR@")
+config.spirv_tools_tests = @LLVM_INCLUDE_SPIRV_TOOLS_TESTS@
+config.targets_to_build = "@TARGETS_TO_BUILD@"
 config.llvm_shlib_ext = "@SHLIBEXT@"
 config.llvm_shlib_dir = lit_config.substitute(path(r"@SHLIBDIR@"))
 config.python_executable = "@Python3_EXECUTABLE@"
@@ -41,7 +43,7 @@ config.mlir_run_amx_tests = @MLIR_RUN_AMX_TESTS@
 config.mlir_run_arm_sve_tests = @MLIR_RUN_ARM_SVE_TESTS@
 # This is a workaround for the fact that LIT's:
 #   %if <cond>
-# requires <cond> to be in the set of available features. 
+# requires <cond> to be in the set of available features.
 # TODO: Update LIT's TestRunner so that this is not required.
 if config.mlir_run_arm_sve_tests:
     config.available_features.add("mlir_arm_sve_tests")