Move storage_class validation from wgsl to resolver

We don't want the WGSL parser to have to maintain type lookups.
If the WGSL language is updated to allow module-scope variables to be declared in any order, then the single-pass approach is going to fail horribly.

Instead do the check in the Resovler.
With this change, the AST nodes actually contain the correctly declared storage class.

Fix up the SPIR-V reader to generate StorageClass::kNone for handle types.
Fix all tests.

Bug: tint:724
Change-Id: I102e30c9bbef32de40e123c2676ea9a281dee74d
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/50306
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Reviewed-by: James Price <jrprice@google.com>

src/ast/intrinsic_texture_helper_test.cc

@@ -158,24 +158,23 @@ ast::Variable* TextureOverloadCase::buildTextureVariable(
       return b->Global("texture",
                        b->ty.sampled_texture(texture_dimension,
                                              buildResultVectorComponentType(b)),
-                       ast::StorageClass::kUniformConstant, nullptr, decos);
+                       ast::StorageClass::kNone, nullptr, decos);
 
     case ast::intrinsic::test::TextureKind::kDepth:
       return b->Global("texture", b->ty.depth_texture(texture_dimension),
-                       ast::StorageClass::kUniformConstant, nullptr, decos);
+                       ast::StorageClass::kNone, nullptr, decos);
 
     case ast::intrinsic::test::TextureKind::kMultisampled:
       return b->Global(
           "texture",
           b->ty.multisampled_texture(texture_dimension,
                                      buildResultVectorComponentType(b)),
-          ast::StorageClass::kUniformConstant, nullptr, decos);
+          ast::StorageClass::kNone, nullptr, decos);
 
     case ast::intrinsic::test::TextureKind::kStorage: {
       auto st = b->ty.storage_texture(texture_dimension, image_format);
       auto ac = b->ty.access(access_control, st);
-      return b->Global("texture", ac, ast::StorageClass::kUniformConstant,
+      return b->Global("texture", ac, ast::StorageClass::kNone, nullptr, decos);
-                       nullptr, decos);
     }
   }
 
@@ -190,7 +189,7 @@ ast::Variable* TextureOverloadCase::buildSamplerVariable(
       b->create<ast::BindingDecoration>(1),
   };
   return b->Global("sampler", b->ty.sampler(sampler_kind),
-                   ast::StorageClass::kUniformConstant, nullptr, decos);
+                   ast::StorageClass::kNone, nullptr, decos);
 }
 
 std::vector<TextureOverloadCase> TextureOverloadCase::ValidCases() {

src/ast/storage_class.cc

@@ -19,6 +19,10 @@ namespace ast {
 
 std::ostream& operator<<(std::ostream& out, StorageClass sc) {
   switch (sc) {
+    case StorageClass::kInvalid: {
+      out << "invalid";
+      break;
+    }
     case StorageClass::kNone: {
       out << "none";
       break;

src/ast/storage_class.h

@@ -22,7 +22,8 @@ namespace ast {
 
 /// Storage class of a given pointer.
 enum class StorageClass {
-  kNone = -1,
+  kInvalid = -1,
+  kNone,
   kInput,
   kOutput,
   kUniform,

src/inspector/inspector_test.cc

@@ -316,8 +316,7 @@ class InspectorHelper : public ProgramBuilder {
   /// @param group the binding/group to use for the storage buffer
   /// @param binding the binding number to use for the storage buffer
   void AddSampler(const std::string& name, uint32_t group, uint32_t binding) {
-    AddBinding(name, sampler_type(), ast::StorageClass::kUniformConstant, group,
+    AddBinding(name, sampler_type(), ast::StorageClass::kNone, group, binding);
-               binding);
   }
 
   /// Adds a comparison sampler variable to the program
@@ -327,8 +326,8 @@ class InspectorHelper : public ProgramBuilder {
   void AddComparisonSampler(const std::string& name,
                             uint32_t group,
                             uint32_t binding) {
-    AddBinding(name, comparison_sampler_type(),
+    AddBinding(name, comparison_sampler_type(), ast::StorageClass::kNone, group,
-               ast::StorageClass::kUniformConstant, group, binding);
+               binding);
   }
 
   /// Generates a SampledTexture appropriate for the params
@@ -366,7 +365,7 @@ class InspectorHelper : public ProgramBuilder {
                          ast::Type* type,
                          uint32_t group,
                          uint32_t binding) {
-    AddBinding(name, type, ast::StorageClass::kUniformConstant, group, binding);
+    AddBinding(name, type, ast::StorageClass::kNone, group, binding);
   }
 
   /// Adds a multi-sampled texture variable to the program
@@ -378,7 +377,7 @@ class InspectorHelper : public ProgramBuilder {
                               ast::Type* type,
                               uint32_t group,
                               uint32_t binding) {
-    AddBinding(name, type, ast::StorageClass::kUniformConstant, group, binding);
+    AddBinding(name, type, ast::StorageClass::kNone, group, binding);
   }
 
   void AddGlobalVariable(const std::string& name, ast::Type* type) {
@@ -394,7 +393,7 @@ class InspectorHelper : public ProgramBuilder {
                        ast::Type* type,
                        uint32_t group,
                        uint32_t binding) {
-    AddBinding(name, type, ast::StorageClass::kUniformConstant, group, binding);
+    AddBinding(name, type, ast::StorageClass::kNone, group, binding);
   }
 
   /// Generates a function that references a specific sampler variable
@@ -566,7 +565,7 @@ class InspectorHelper : public ProgramBuilder {
                          typ::Type type,
                          uint32_t group,
                          uint32_t binding) {
-    AddBinding(name, type, ast::StorageClass::kUniformConstant, group, binding);
+    AddBinding(name, type, ast::StorageClass::kNone, group, binding);
   }
 
   /// Generates a function that references a storage texture variable.

src/reader/spirv/enum_converter.cc

@@ -49,7 +49,7 @@ ast::StorageClass EnumConverter::ToStorageClass(const SpvStorageClass sc) {
     case SpvStorageClassWorkgroup:
       return ast::StorageClass::kWorkgroup;
     case SpvStorageClassUniformConstant:
-      return ast::StorageClass::kUniformConstant;
+      return ast::StorageClass::kNone;
     case SpvStorageClassStorageBuffer:
       return ast::StorageClass::kStorage;
     case SpvStorageClassImage:
@@ -63,7 +63,7 @@ ast::StorageClass EnumConverter::ToStorageClass(const SpvStorageClass sc) {
   }
 
   Fail() << "unknown SPIR-V storage class: " << uint32_t(sc);
-  return ast::StorageClass::kNone;
+  return ast::StorageClass::kInvalid;
 }
 
 ast::Builtin EnumConverter::ToBuiltin(SpvBuiltIn b) {

src/reader/spirv/enum_converter_test.cc

@@ -143,7 +143,7 @@ INSTANTIATE_TEST_SUITE_P(
         StorageClassCase{SpvStorageClassWorkgroup, true,
                          ast::StorageClass::kWorkgroup},
         StorageClassCase{SpvStorageClassUniformConstant, true,
-                         ast::StorageClass::kUniformConstant},
+                         ast::StorageClass::kNone},
         StorageClassCase{SpvStorageClassStorageBuffer, true,
                          ast::StorageClass::kStorage},
         StorageClassCase{SpvStorageClassImage, true, ast::StorageClass::kImage},
@@ -156,7 +156,7 @@ INSTANTIATE_TEST_SUITE_P(EnumConverterBad,
                          SpvStorageClassTest,
                          testing::Values(StorageClassCase{
                              static_cast<SpvStorageClass>(9999), false,
-                             ast::StorageClass::kNone}));
+                             ast::StorageClass::kInvalid}));
 
 // Builtin
 

src/reader/spirv/function.cc

@@ -4005,11 +4005,13 @@ bool FunctionEmitter::RegisterLocallyDefinedValues() {
                      << "pointer defined in function from unknown opcode: "
                      << inst.PrettyPrint();
           }
-          if (info->storage_class == ast::StorageClass::kUniformConstant) {
-            info->skip = SkipReason::kOpaqueObject;
-          }
         }
-        if (type->AsSampler() || type->AsImage() || type->AsSampledImage()) {
+        auto* unwrapped = type;
+        while (auto* ptr = unwrapped->AsPointer()) {
+          unwrapped = ptr->pointee_type();
+        }
+        if (unwrapped->AsSampler() || unwrapped->AsImage() ||
+            unwrapped->AsSampledImage()) {
           // Defer code generation until the instruction that actually acts on
           // the image.
           info->skip = SkipReason::kOpaqueObject;
@@ -4032,7 +4034,7 @@ ast::StorageClass FunctionEmitter::GetStorageClassForPointerValue(uint32_t id) {
       return ptr->storage_class;
     }
   }
-  return ast::StorageClass::kNone;
+  return ast::StorageClass::kInvalid;
 }
 
 const Type* FunctionEmitter::RemapStorageClass(const Type* type,

src/reader/spirv/parser_impl.cc

@@ -1060,7 +1060,7 @@ const Type* ParserImpl::ConvertType(uint32_t type_id,
   }
 
   auto ast_storage_class = enum_converter_.ToStorageClass(storage_class);
-  if (ast_storage_class == ast::StorageClass::kNone) {
+  if (ast_storage_class == ast::StorageClass::kInvalid) {
     Fail() << "SPIR-V pointer type with ID " << type_id
            << " has invalid storage class "
            << static_cast<uint32_t>(storage_class);
@@ -1236,6 +1236,7 @@ bool ParserImpl::EmitModuleScopeVariables() {
       continue;
     }
     switch (enum_converter_.ToStorageClass(spirv_storage_class)) {
+      case ast::StorageClass::kNone:
       case ast::StorageClass::kInput:
       case ast::StorageClass::kOutput:
       case ast::StorageClass::kUniform:

src/reader/spirv/parser_impl_convert_type_test.cc

@@ -692,7 +692,7 @@ TEST_F(SpvParserTest, ConvertType_PointerUniformConstant) {
   auto* ptr_ty = type->As<Pointer>();
   EXPECT_NE(ptr_ty, nullptr);
   EXPECT_TRUE(ptr_ty->type->Is<F32>());
-  EXPECT_EQ(ptr_ty->storage_class, ast::StorageClass::kUniformConstant);
+  EXPECT_EQ(ptr_ty->storage_class, ast::StorageClass::kNone);
   EXPECT_TRUE(p->error().empty());
 }
 

src/reader/wgsl/parser_impl.cc

@@ -564,17 +564,6 @@ Maybe<ParserImpl::VarDeclInfo> ParserImpl::variable_decl() {
   if (decl.errored)
     return Failure::kErrored;
 
-  if (decl->type && decl->type->UnwrapAll()->is_handle()) {
-    // handle types implicitly have the `UniformConstant` storage class.
-    if (explicit_sc.matched) {
-      return add_error(
-          explicit_sc.source,
-          decl->type->UnwrapAll()->FriendlyName(builder_.Symbols()) +
-              " variables must not have a storage class");
-    }
-    sc = ast::StorageClass::kUniformConstant;
-  }
-
   return VarDeclInfo{decl->source, decl->name, sc, decl->type};
 }
 

src/reader/wgsl/parser_impl_error_msg_test.cc

@@ -1102,22 +1102,6 @@ TEST_F(ParserImplErrorTest, GlobalDeclVarVectorMissingType) {
          "             ^\n");
 }
 
-TEST_F(ParserImplErrorTest, GlobalDeclSamplerExplicitStorageClass) {
-  EXPECT(
-      "var<uniform> x : sampler;",
-      "test.wgsl:1:5 error: sampler variables must not have a storage class\n"
-      "var<uniform> x : sampler;\n"
-      "    ^^^^^^^\n");
-}
-
-TEST_F(ParserImplErrorTest, GlobalDeclTextureExplicitStorageClass) {
-  EXPECT("var<uniform> x : [[access(read)]] texture_1d<f32>;",
-         "test.wgsl:1:5 error: texture_1d<f32> variables must not have a "
-         "storage class\n"
-         "var<uniform> x : [[access(read)]] texture_1d<f32>;\n"
-         "    ^^^^^^^\n");
-}
-
 TEST_F(ParserImplErrorTest, IfStmtMissingLParen) {
   EXPECT("fn f() { if true) {} }",
          "test.wgsl:1:13 error: expected '('\n"

src/reader/wgsl/parser_impl_global_variable_decl_test.cc

@@ -168,38 +168,6 @@ TEST_F(ParserImplTest, GlobalVariableDecl_InvalidVariableDecl) {
   EXPECT_EQ(p->error(), "1:5: invalid storage class for variable decoration");
 }
 
-TEST_F(ParserImplTest, GlobalVariableDecl_SamplerImplicitStorageClass) {
-  auto p = parser("var s : sampler;");
-  auto decos = p->decoration_list();
-  EXPECT_FALSE(decos.errored);
-  EXPECT_FALSE(decos.matched);
-  auto e = p->global_variable_decl(decos.value);
-  ASSERT_FALSE(p->has_error()) << p->error();
-  EXPECT_FALSE(e.errored);
-  EXPECT_TRUE(e.matched);
-  ASSERT_NE(e.value, nullptr);
-
-  EXPECT_EQ(e->symbol(), p->builder().Symbols().Get("s"));
-  EXPECT_TRUE(e->type()->Is<ast::Sampler>());
-  EXPECT_EQ(e->declared_storage_class(), ast::StorageClass::kUniformConstant);
-}
-
-TEST_F(ParserImplTest, GlobalVariableDecl_TextureImplicitStorageClass) {
-  auto p = parser("var s : [[access(read)]] texture_1d<f32>;");
-  auto decos = p->decoration_list();
-  EXPECT_FALSE(decos.errored);
-  EXPECT_FALSE(decos.matched);
-  auto e = p->global_variable_decl(decos.value);
-  ASSERT_FALSE(p->has_error()) << p->error();
-  EXPECT_FALSE(e.errored);
-  EXPECT_TRUE(e.matched);
-  ASSERT_NE(e.value, nullptr);
-
-  EXPECT_EQ(e->symbol(), p->builder().Symbols().Get("s"));
-  EXPECT_TRUE(e->type()->UnwrapAll()->Is<ast::Texture>());
-  EXPECT_EQ(e->declared_storage_class(), ast::StorageClass::kUniformConstant);
-}
-
 TEST_F(ParserImplTest, GlobalVariableDecl_StorageClassIn_Deprecated) {
   auto p = parser("[[location(0)]] var<in> a : f32");
   auto f = p->function_header();

src/resolver/assignment_validation_test.cc

@@ -244,19 +244,15 @@ TEST_F(ResolverAssignmentValidationTest, AssignFromPointer_Fail) {
     return ty.access(ast::AccessControl::kReadOnly, tex_type);
   };
 
-  auto* var_a = Var("a", make_type(), ast::StorageClass::kFunction);
+  auto* var_a = Global("a", make_type(), ast::StorageClass::kNone);
-  auto* var_b = Var("b", make_type(), ast::StorageClass::kFunction);
+  auto* var_b = Global("b", make_type(), ast::StorageClass::kNone);
 
-  auto* lhs = Expr("a");
+  WrapInFunction(Assign(Source{{12, 34}}, var_a, var_b));
-  auto* rhs = Expr("b");
-
-  auto* assign = Assign(Source{{12, 34}}, lhs, rhs);
-  WrapInFunction(Decl(var_a), Decl(var_b), assign);
 
   EXPECT_FALSE(r()->Resolve());
   EXPECT_EQ(r()->error(),
             "12:34 error v-000x: invalid assignment: right-hand-side is not "
-            "storable: ptr<function, [[access(read)]] "
+            "storable: ptr<uniform_constant, [[access(read)]] "
             "texture_storage_1d<rgba8unorm>>");
 }
 

src/resolver/intrinsic_test.cc

@@ -243,7 +243,10 @@ class ResolverIntrinsicTest_TextureOperation
   void add_call_param(std::string name,
                       typ::Type type,
                       ast::ExpressionList* call_params) {
-    Global(name, type, ast::StorageClass::kInput);
+    ast::StorageClass storage_class = type->UnwrapAll()->is_handle()
+                                          ? ast::StorageClass::kNone
+                                          : ast::StorageClass::kPrivate;
+    Global(name, type, storage_class);
     call_params->push_back(Expr(name));
   }
   typ::Type subtype(Texture type) {

src/resolver/resolver.cc

@@ -500,7 +500,7 @@ bool Resolver::GlobalVariable(ast::Variable* var) {
     return false;
   }
 
-  if (!ApplyStorageClassUsageToType(var->declared_storage_class(), info->type,
+  if (!ApplyStorageClassUsageToType(info->storage_class, info->type,
                                     var->source())) {
     diagnostics_.add_note("while instantiating variable " +
                               builder_->Symbols().NameFor(var->symbol()),
@@ -577,11 +577,12 @@ bool Resolver::ValidateGlobalVariable(const VariableInfo* info) {
       break;
   }
 
-  return ValidateVariable(info->declaration);
+  return ValidateVariable(info);
 }
 
-bool Resolver::ValidateVariable(const ast::Variable* var) {
+bool Resolver::ValidateVariable(const VariableInfo* info) {
-  auto* type = variable_to_info_[var]->type;
+  auto* var = info->declaration;
+  auto* type = info->type;
   if (auto* r = type->As<sem::Array>()) {
     if (r->IsRuntimeSized()) {
       diagnostics_.add_error(
@@ -643,11 +644,23 @@ bool Resolver::ValidateVariable(const ast::Variable* var) {
     }
   }
 
+  if (type->UnwrapAll()->is_handle() &&
+      var->declared_storage_class() != ast::StorageClass::kNone) {
+    // https://gpuweb.github.io/gpuweb/wgsl/#module-scope-variables
+    // If the store type is a texture type or a sampler type, then the variable
+    // declaration must not have a storage class decoration. The storage class
+    // will always be handle.
+    diagnostics_.add_error("variables of type '" + info->type_name +
+                               "' must not have a storage class",
+                           var->source());
+    return false;
+  }
+
   return true;
 }
 
-bool Resolver::ValidateParameter(const ast::Variable* param) {
+bool Resolver::ValidateParameter(const VariableInfo* info) {
-  return ValidateVariable(param);
+  return ValidateVariable(info);
 }
 
 bool Resolver::ValidateFunction(const ast::Function* func,
@@ -662,7 +675,7 @@ bool Resolver::ValidateFunction(const ast::Function* func,
   }
 
   for (auto* param : func->params()) {
-    if (!ValidateParameter(param)) {
+    if (!ValidateParameter(variable_to_info_.at(param))) {
       return false;
     }
   }
@@ -2060,7 +2073,7 @@ bool Resolver::VariableDeclStatement(const ast::VariableDeclStatement* stmt) {
   variable_stack_.set(var->symbol(), info);
   current_block_->decls.push_back(var);
 
-  if (!ValidateVariable(var)) {
+  if (!ValidateVariable(info)) {
     return false;
   }
 
@@ -2833,7 +2846,16 @@ Resolver::VariableInfo::VariableInfo(const ast::Variable* decl,
     : declaration(decl),
       type(ctype),
       type_name(tn),
-      storage_class(decl->declared_storage_class()) {}
+      storage_class(decl->declared_storage_class()) {
+  if (storage_class == ast::StorageClass::kNone &&
+      type->UnwrapAll()->is_handle()) {
+    // https://gpuweb.github.io/gpuweb/wgsl/#module-scope-variables
+    // If the store type is a texture type or a sampler type, then the variable
+    // declaration must not have a storage class decoration. The storage class
+    // will always be handle.
+    storage_class = ast::StorageClass::kUniformConstant;
+  }
+}
 
 Resolver::VariableInfo::~VariableInfo() = default;
 

src/resolver/resolver.h

@@ -230,11 +230,11 @@ class Resolver {
   bool ValidateGlobalVariable(const VariableInfo* var);
   bool ValidateMatrixConstructor(const ast::TypeConstructorExpression* ctor,
                                  const sem::Matrix* matrix_type);
-  bool ValidateParameter(const ast::Variable* param);
+  bool ValidateParameter(const VariableInfo* info);
   bool ValidateReturn(const ast::ReturnStatement* ret);
   bool ValidateStructure(const sem::Struct* str);
   bool ValidateSwitch(const ast::SwitchStatement* s);
-  bool ValidateVariable(const ast::Variable* param);
+  bool ValidateVariable(const VariableInfo* info);
   bool ValidateVectorConstructor(const ast::TypeConstructorExpression* ctor,
                                  const sem::Vector* vec_type);
 

src/resolver/resolver_test.cc

@@ -1458,6 +1458,27 @@ TEST_F(ResolverTest, StorageClass_SetsIfMissing) {
   EXPECT_EQ(Sem().Get(var)->StorageClass(), ast::StorageClass::kFunction);
 }
 
+TEST_F(ResolverTest, StorageClass_SetForSampler) {
+  auto t = ty.sampler(ast::SamplerKind::kSampler);
+  auto* var = Global("var", t, ast::StorageClass::kNone);
+
+  EXPECT_TRUE(r()->Resolve()) << r()->error();
+
+  EXPECT_EQ(Sem().Get(var)->StorageClass(),
+            ast::StorageClass::kUniformConstant);
+}
+
+TEST_F(ResolverTest, StorageClass_SetForTexture) {
+  auto t = ty.sampled_texture(ast::TextureDimension::k1d, ty.f32());
+  auto ac = ty.access(ast::AccessControl::Access::kReadOnly, t);
+  auto* var = Global("var", ac, ast::StorageClass::kNone);
+
+  EXPECT_TRUE(r()->Resolve()) << r()->error();
+
+  EXPECT_EQ(Sem().Get(var)->StorageClass(),
+            ast::StorageClass::kUniformConstant);
+}
+
 TEST_F(ResolverTest, StorageClass_DoesNotSetOnConst) {
   auto* var = Const("var", ty.i32(), Construct(ty.i32()));
   auto* stmt = Decl(var);

src/resolver/type_validation_test.cc

@@ -551,7 +551,7 @@ using MultisampledTextureDimensionTest = ResolverTestWithParam<DimensionParams>;
 TEST_P(MultisampledTextureDimensionTest, All) {
   auto& params = GetParam();
   Global("a", ty.multisampled_texture(params.dim, ty.i32()),
-         ast::StorageClass::kUniformConstant, nullptr,
+         ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),
@@ -595,7 +595,7 @@ TEST_P(MultisampledTextureTypeTest, All) {
   Global(
       "a",
       ty.multisampled_texture(ast::TextureDimension::k2d, params.type_func(ty)),
-      ast::StorageClass::kUniformConstant, nullptr,
+      ast::StorageClass::kNone, nullptr,
       ast::DecorationList{
           create<ast::BindingDecoration>(0),
           create<ast::GroupDecoration>(0),
@@ -636,7 +636,7 @@ TEST_P(StorageTextureDimensionTest, All) {
   auto st = ty.storage_texture(params.dim, ast::ImageFormat::kR32Uint);
   auto ac = ty.access(ast::AccessControl::kReadOnly, st);
 
-  Global("a", ac, ast::StorageClass::kUniformConstant, nullptr,
+  Global("a", ac, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),
@@ -708,7 +708,7 @@ TEST_P(StorageTextureFormatTest, All) {
 
   auto st_a = ty.storage_texture(ast::TextureDimension::k1d, params.format);
   auto ac_a = ty.access(ast::AccessControl::kReadOnly, st_a);
-  Global("a", ac_a, ast::StorageClass::kUniformConstant, nullptr,
+  Global("a", ac_a, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),
@@ -716,7 +716,7 @@ TEST_P(StorageTextureFormatTest, All) {
 
   auto st_b = ty.storage_texture(ast::TextureDimension::k2d, params.format);
   auto ac_b = ty.access(ast::AccessControl::kReadOnly, st_b);
-  Global("b", ac_b, ast::StorageClass::kUniformConstant, nullptr,
+  Global("b", ac_b, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(1),
@@ -725,7 +725,7 @@ TEST_P(StorageTextureFormatTest, All) {
   auto st_c =
       ty.storage_texture(ast::TextureDimension::k2dArray, params.format);
   auto ac_c = ty.access(ast::AccessControl::kReadOnly, st_c);
-  Global("c", ac_c, ast::StorageClass::kUniformConstant, nullptr,
+  Global("c", ac_c, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(2),
@@ -733,7 +733,7 @@ TEST_P(StorageTextureFormatTest, All) {
 
   auto st_d = ty.storage_texture(ast::TextureDimension::k3d, params.format);
   auto ac_d = ty.access(ast::AccessControl::kReadOnly, st_d);
-  Global("d", ac_d, ast::StorageClass::kUniformConstant, nullptr,
+  Global("d", ac_d, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(3),
@@ -758,7 +758,7 @@ TEST_F(StorageTextureAccessControlTest, MissingAccessControl_Fail) {
   auto st = ty.storage_texture(ast::TextureDimension::k1d,
                                ast::ImageFormat::kR32Uint);
 
-  Global("a", st, ast::StorageClass::kUniformConstant, nullptr,
+  Global("a", st, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),
@@ -775,7 +775,7 @@ TEST_F(StorageTextureAccessControlTest, RWAccessControl_Fail) {
                                ast::ImageFormat::kR32Uint);
   auto ac = ty.access(ast::AccessControl::kReadWrite, st);
 
-  Global("a", ac, ast::StorageClass::kUniformConstant, nullptr,
+  Global("a", ac, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),
@@ -792,7 +792,7 @@ TEST_F(StorageTextureAccessControlTest, ReadOnlyAccessControl_Pass) {
                                ast::ImageFormat::kR32Uint);
   auto ac = ty.access(ast::AccessControl::kReadOnly, st);
 
-  Global("a", ac, ast::StorageClass::kUniformConstant, nullptr,
+  Global("a", ac, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),
@@ -809,7 +809,7 @@ TEST_F(StorageTextureAccessControlTest, WriteOnlyAccessControl_Pass) {
                                ast::ImageFormat::kR32Uint);
   auto ac = ty.access(ast::AccessControl::kWriteOnly, st);
 
-  Global("a", ac, ast::StorageClass::kUniformConstant, nullptr,
+  Global("a", ac, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
              create<ast::GroupDecoration>(0),

src/resolver/validation_test.cc

@@ -375,6 +375,28 @@ TEST_F(ResolverValidationTest, StorageClass_NonFunctionClassError) {
             "error: function variable has a non-function storage class");
 }
 
+TEST_F(ResolverValidationTest, StorageClass_SamplerExplicitStorageClass) {
+  auto t = ty.sampler(ast::SamplerKind::kSampler);
+  Global(Source{{12, 34}}, "var", t, ast::StorageClass::kUniformConstant);
+
+  EXPECT_FALSE(r()->Resolve());
+
+  EXPECT_EQ(
+      r()->error(),
+      R"(12:34 error: variables of type 'sampler' must not have a storage class)");
+}
+
+TEST_F(ResolverValidationTest, StorageClass_TextureExplicitStorageClass) {
+  auto t = ty.sampled_texture(ast::TextureDimension::k1d, ty.f32());
+  Global(Source{{12, 34}}, "var", t, ast::StorageClass::kUniformConstant);
+
+  EXPECT_FALSE(r()->Resolve()) << r()->error();
+
+  EXPECT_EQ(
+      r()->error(),
+      R"(12:34 error: variables of type 'texture_1d<f32>' must not have a storage class)");
+}
+
 TEST_F(ResolverValidationTest, Expr_MemberAccessor_VectorSwizzle_BadChar) {
   Global("my_vec", ty.vec3<f32>(), ast::StorageClass::kInput);
 

src/writer/hlsl/generator_impl_type_test.cc

@@ -335,7 +335,7 @@ TEST_P(HlslDepthTexturesTest, Emit) {
 
   auto t = ty.depth_texture(params.dim);
 
-  Global("tex", t, ast::StorageClass::kUniformConstant, nullptr,
+  Global("tex", t, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(1),
              create<ast::GroupDecoration>(2),
@@ -394,7 +394,7 @@ TEST_P(HlslSampledTexturesTest, Emit) {
   }
   auto t = ty.sampled_texture(params.dim, datatype);
 
-  Global("tex", t, ast::StorageClass::kUniformConstant, nullptr,
+  Global("tex", t, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(1),
              create<ast::GroupDecoration>(2),
@@ -536,7 +536,7 @@ TEST_P(HlslStorageTexturesTest, Emit) {
                                 : ast::AccessControl::kWriteOnly,
                       t);
 
-  Global("tex", ac, ast::StorageClass::kUniformConstant, nullptr,
+  Global("tex", ac, ast::StorageClass::kNone, nullptr,
          ast::DecorationList{
              create<ast::BindingDecoration>(1),
              create<ast::GroupDecoration>(2),

src/writer/msl/generator_impl_type_test.cc

@@ -745,7 +745,7 @@ TEST_P(MslStorageTexturesTest, Emit) {
   auto ac = ty.access(params.ro ? ast::AccessControl::kReadOnly
                                 : ast::AccessControl::kWriteOnly,
                       s);
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   GeneratorImpl& gen = Build();
 

src/writer/spirv/builder.cc

@@ -769,8 +769,8 @@ bool Builder::GenerateGlobalVariable(ast::Variable* var) {
     if (auto* builtin = deco->As<ast::BuiltinDecoration>()) {
       push_annot(spv::Op::OpDecorate,
                  {Operand::Int(var_id), Operand::Int(SpvDecorationBuiltIn),
-                  Operand::Int(ConvertBuiltin(builtin->value(),
+                  Operand::Int(
-                                              var->declared_storage_class()))});
+                      ConvertBuiltin(builtin->value(), sem->StorageClass()))});
     } else if (auto* location = deco->As<ast::LocationDecoration>()) {
       push_annot(spv::Op::OpDecorate,
                  {Operand::Int(var_id), Operand::Int(SpvDecorationLocation),
@@ -3243,6 +3243,8 @@ bool Builder::GenerateVectorType(const sem::Vector* vec,
 
 SpvStorageClass Builder::ConvertStorageClass(ast::StorageClass klass) const {
   switch (klass) {
+    case ast::StorageClass::kInvalid:
+      return SpvStorageClassMax;
     case ast::StorageClass::kInput:
       return SpvStorageClassInput;
     case ast::StorageClass::kOutput:

src/writer/spirv/builder_global_variable_test.cc

@@ -526,7 +526,7 @@ TEST_F(BuilderTest, GlobalVar_TextureStorageReadOnly) {
 
   auto ac = ty.access(ast::AccessControl::kReadOnly, type);
 
-  auto* var_a = Global("a", ac, ast::StorageClass::kUniformConstant);
+  auto* var_a = Global("a", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -549,7 +549,7 @@ TEST_F(BuilderTest, GlobalVar_TextureStorageWriteOnly) {
 
   auto ac = ty.access(ast::AccessControl::kWriteOnly, type);
 
-  auto* var_a = Global("a", ac, ast::StorageClass::kUniformConstant);
+  auto* var_a = Global("a", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -573,12 +573,12 @@ TEST_F(BuilderTest, GlobalVar_TextureStorageWithDifferentAccess) {
   auto type_a = ty.access(ast::AccessControl::kReadOnly,
                           ty.storage_texture(ast::TextureDimension::k2d,
                                              ast::ImageFormat::kR32Uint));
-  auto* var_a = Global("a", type_a, ast::StorageClass::kUniformConstant);
+  auto* var_a = Global("a", type_a, ast::StorageClass::kNone);
 
   auto type_b = ty.access(ast::AccessControl::kWriteOnly,
                           ty.storage_texture(ast::TextureDimension::k2d,
                                              ast::ImageFormat::kR32Uint));
-  auto* var_b = Global("b", type_b, ast::StorageClass::kUniformConstant);
+  auto* var_b = Global("b", type_b, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 

src/writer/spirv/builder_intrinsic_test.cc

@@ -373,9 +373,9 @@ TEST_F(IntrinsicBuilderTest, Call_TextureSampleCompare_Twice) {
   auto s = ty.sampler(ast::SamplerKind::kComparisonSampler);
   auto t = ty.depth_texture(ast::TextureDimension::k2d);
 
-  auto* tex = Global("texture", t, ast::StorageClass::kInput);
+  auto* tex = Global("texture", t, ast::StorageClass::kNone);
 
-  auto* sampler = Global("sampler", s, ast::StorageClass::kInput);
+  auto* sampler = Global("sampler", s, ast::StorageClass::kNone);
 
   auto* expr1 = Call("textureSampleCompare", "texture", "sampler",
                      vec2<f32>(1.0f, 2.0f), 2.0f);
@@ -397,11 +397,11 @@ TEST_F(IntrinsicBuilderTest, Call_TextureSampleCompare_Twice) {
 
   EXPECT_EQ(DumpInstructions(b.types()), R"(%4 = OpTypeFloat 32
 %3 = OpTypeImage %4 2D 1 0 0 1 Unknown
-%2 = OpTypePointer Input %3
+%2 = OpTypePointer UniformConstant %3
-%1 = OpVariable %2 Input
+%1 = OpVariable %2 UniformConstant
 %7 = OpTypeSampler
-%6 = OpTypePointer Input %7
+%6 = OpTypePointer UniformConstant %7
-%5 = OpVariable %6 Input
+%5 = OpVariable %6 UniformConstant
 %11 = OpTypeSampledImage %3
 %13 = OpTypeVector %4 2
 %14 = OpConstant %4 1

src/writer/spirv/builder_type_test.cc

@@ -816,7 +816,7 @@ TEST_F(BuilderTest_Type, StorageTexture_Generate_1d) {
                               ast::ImageFormat::kR32Float);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -832,7 +832,7 @@ TEST_F(BuilderTest_Type, StorageTexture_Generate_2d) {
                               ast::ImageFormat::kR32Float);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -848,7 +848,7 @@ TEST_F(BuilderTest_Type, StorageTexture_Generate_2dArray) {
                               ast::ImageFormat::kR32Float);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -864,7 +864,7 @@ TEST_F(BuilderTest_Type, StorageTexture_Generate_3d) {
                               ast::ImageFormat::kR32Float);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -881,7 +881,7 @@ TEST_F(BuilderTest_Type,
                               ast::ImageFormat::kR32Float);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -898,7 +898,7 @@ TEST_F(BuilderTest_Type,
                               ast::ImageFormat::kR32Sint);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 
@@ -915,7 +915,7 @@ TEST_F(BuilderTest_Type,
                               ast::ImageFormat::kR32Uint);
   auto ac = ty.access(ast::AccessControl::kReadOnly, s);
 
-  Global("test_var", ac, ast::StorageClass::kInput);
+  Global("test_var", ac, ast::StorageClass::kNone);
 
   spirv::Builder& b = Build();
 

src/writer/wgsl/generator_impl_global_decl_test.cc

@@ -101,8 +101,7 @@ TEST_F(WgslGeneratorImplTest, Emit_GlobalsInterleaved) {
 }
 
 TEST_F(WgslGeneratorImplTest, Emit_Global_Sampler) {
-  Global("s", ty.sampler(ast::SamplerKind::kSampler),
+  Global("s", ty.sampler(ast::SamplerKind::kSampler), ast::StorageClass::kNone);
-         ast::StorageClass::kUniformConstant);
 
   GeneratorImpl& gen = Build();
 
@@ -115,7 +114,7 @@ TEST_F(WgslGeneratorImplTest, Emit_Global_Sampler) {
 TEST_F(WgslGeneratorImplTest, Emit_Global_Texture) {
   auto st = ty.sampled_texture(ast::TextureDimension::k1d, ty.f32());
   Global("t", ty.access(ast::AccessControl::kReadOnly, st),
-         ast::StorageClass::kUniformConstant);
+         ast::StorageClass::kNone);
 
   GeneratorImpl& gen = Build();