Allow expression of scalar tensor buffers, non string values in variants (#4292)

Summary:
Pull Request resolved: #4292

Some simple improvements to the SPIR-V compilation script:

1. Allow `layout_declare_tensor` to create a scalar buffer instead of always creating a vectorized buffer
2. Allow handling of non-string (i.e. int) values in shader codegen YAML configurations.

Reviewed By: jorgep31415

Differential Revision: D59877805

fbshipit-source-id: 579888fbc19d19a0d24f2fbd831e74f4ba32f033

Author: SS-JIA

backends/vulkan/runtime/gen_vulkan_spv.py

@@ -231,6 +231,7 @@ def layout_declare_tensor(
     var_name: str,
     dtype: str,
     storage_type: str,
+    is_scalar_array: bool = False,
     precision: str = "PRECISION",
 ) -> str:
     assert storage_type.lower() in ["buffer", "texture3d", "texture2d"]
@@ -242,7 +243,12 @@ def layout_declare_tensor(
     # Create buffer binding
     if storage_type.lower() == "buffer":
         return layout_declare_buffer(
-            slot, access_type, var_name, dtype, precision, is_scalar_array=False
+            slot,
+            access_type,
+            var_name,
+            dtype,
+            precision,
+            is_scalar_array=is_scalar_array,
         )
 
     # Create image/sampler binding
@@ -533,7 +539,7 @@ def generateVariantCombinations(
                                 curr_suffix = (
                                     suffix + "_" + str(i) if suffix else str(i)
                                 )
-                                param_values.append((param_name, curr_suffix, str(i)))
+                                param_values.append((param_name, curr_suffix, i))
                         else:
                             raise ValueError(
                                 f"{value['RANGE']} is not a valid range. Must be in format [start, end] (inclusive)."
@@ -595,7 +601,7 @@ def parseTemplateYaml(self, yaml_file: str) -> None:
                             variant_name = variant["NAME"]
                             for param_value in combination:
                                 default_params_copy[param_value[0]] = param_value[2]
-                                if len(param_value[1]) > 0:
+                                if len(str(param_value[1])) > 0:
                                     variant_name = f"{variant_name}_{param_value[1]}"
 
                             default_params_copy["NAME"] = variant_name