[spirv-reader][ir] Add validation for struct member matrix annotations.

Add validation that the struct member annotations for row major and
matrix stride are not used. Add a capability to allow them.

Bug: 426198644, 426198893
Change-Id: I87cae4efb264b90ece5b6cf6f5fd398db608378f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/249034
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: dan sinclair <dsinclair@chromium.org>

src/tint/lang/core/ir/validator.cc

diff --git a/src/tint/lang/core/ir/validator.cc b/src/tint/lang/core/ir/validator.cc
index 85be9c9..3989869 100644
--- a/src/tint/lang/core/ir/validator.cc
+++ b/src/tint/lang/core/ir/validator.cc
@@ -1843,6 +1843,23 @@
 
         return tint::Switch(
             type,
+            [&](const core::type::Struct* str) {
+                if (capabilities_.Contains(Capability::kAllowStructMatrixDecorations)) {
+                    return true;
+                }
+
+                for (auto* member : str->Members()) {
+                    if (member->RowMajor()) {
+                        diag() << "Row major annotation now allowed on structures";
+                        return false;
+                    }
+                    if (member->HasMatrixStride()) {
+                        diag() << "Matrix stride annotation not allowed on structures";
+                        return false;
+                    }
+                }
+                return true;
+            },
             [&](const core::type::Reference* ref) {
                 if (ref->StoreType()->Is<core::type::Void>()) {
                     diag() << "references to void are not permitted";

src/tint/lang/core/ir/validator.h

diff --git a/src/tint/lang/core/ir/validator.h b/src/tint/lang/core/ir/validator.h
index 36f9ed2..bed083f 100644
--- a/src/tint/lang/core/ir/validator.h
+++ b/src/tint/lang/core/ir/validator.h
@@ -79,6 +79,8 @@
     kAllowUnannotatedModuleIOVariables,
     /// Allows non-core types in the IR module
     kAllowNonCoreTypes,
+    /// Allows matrix annotations on structure members
+    kAllowStructMatrixDecorations,
 };
 
 /// Capabilities is a set of Capability

src/tint/lang/spirv/reader/parser/helper_test.h

diff --git a/src/tint/lang/spirv/reader/parser/helper_test.h b/src/tint/lang/spirv/reader/parser/helper_test.h
index 6c09bfa..61de210 100644
--- a/src/tint/lang/spirv/reader/parser/helper_test.h
+++ b/src/tint/lang/spirv/reader/parser/helper_test.h
@@ -85,6 +85,7 @@
                                         core::ir::Capability::kAllowPhonyInstructions,
                                         core::ir::Capability::kAllowVectorElementPointer,
                                         core::ir::Capability::kAllowNonCoreTypes,
+                                        core::ir::Capability::kAllowStructMatrixDecorations,
                                     });
         if (validated != Success) {
             return validated.Failure();