From bcab9d05737d396af7166c882baf26985f78cc56 Mon Sep 17 00:00:00 2001
From: Mergen Nachin <mnachin@meta.com>
Date: Tue, 29 Sep 2026 11:02:04 -0400
Subject: [PATCH] [INITIAL] Recreate the Vulkan transformer and conformance
 stack with ghstack

[ghstack-poisoned]
---
 .github/workflows/pull.yml                    |  1 +
 .../serialization/vulkan_graph_builder.py     |  8 +-----
 backends/vulkan/test/targets.bzl              | 11 ++++++++
 .../vulkan/test/test_vulkan_graph_builder.py  | 28 +++++++++++++++++++
 4 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/pull.yml b/.github/workflows/pull.yml
index 2f91799b9a4..a70a824f223 100644
--- a/.github/workflows/pull.yml
+++ b/.github/workflows/pull.yml
@@ -1682,6 +1682,7 @@ jobs:
         # route in the future.
         python -m unittest backends/vulkan/test/test_vulkan_delegate.py -k "*pt2e*"
         python -m unittest backends/vulkan/test/test_vulkan_delegate.py -k "*torchao*"
+        python -m unittest backends/vulkan/test/test_vulkan_graph_builder.py
 
   test-coreml-bc-macos:
     needs: [changed-files, run-decision]
diff --git a/backends/vulkan/serialization/vulkan_graph_builder.py b/backends/vulkan/serialization/vulkan_graph_builder.py
index 3de60966422..8703d391ce0 100644
--- a/backends/vulkan/serialization/vulkan_graph_builder.py
+++ b/backends/vulkan/serialization/vulkan_graph_builder.py
@@ -231,13 +231,7 @@ def create_null_value(self) -> int:
         return new_id
 
     def get_or_create_scalar_value(self, scalar: _ScalarType) -> int:
-        scalar_key = scalar
-        # Since Python considers 1 and True to be "equivalent" (as well as 0 and False)
-        # to distinguish entries in the dictionary, if scalar is bool then convert it
-        # to a string representation to use as a key for the dictionary
-        if isinstance(scalar, bool):
-            scalar_key = str(scalar)
-
+        scalar_key = (type(scalar), repr(scalar))
         if scalar_key in self.const_scalar_to_value_ids:
             return self.const_scalar_to_value_ids[scalar_key]
 
diff --git a/backends/vulkan/test/targets.bzl b/backends/vulkan/test/targets.bzl
index 77e74f9c8fc..5734e733195 100644
--- a/backends/vulkan/test/targets.bzl
+++ b/backends/vulkan/test/targets.bzl
@@ -29,6 +29,17 @@ def define_common_targets(is_fbcode = False):
             ],
         )
 
+        python_unittest(
+            name = "test_vulkan_graph_builder",
+            srcs = ["test_vulkan_graph_builder.py"],
+            deps = [
+                "//caffe2:torch",
+                "//executorch/backends/vulkan/serialization:lib",
+                "//executorch/backends/vulkan:vulkan_preprocess",
+                "//executorch/exir:lib",
+            ],
+        )
+
         python_unittest(
             name = "test_vulkan_passes",
             srcs = [
diff --git a/backends/vulkan/test/test_vulkan_graph_builder.py b/backends/vulkan/test/test_vulkan_graph_builder.py
index 65afc3a2542..c180308e77a 100644
--- a/backends/vulkan/test/test_vulkan_graph_builder.py
+++ b/backends/vulkan/test/test_vulkan_graph_builder.py
@@ -8,12 +8,40 @@
 
 import torch
 from executorch.backends.vulkan.serialization.vulkan_graph_builder import VkGraphBuilder
+from executorch.backends.vulkan.serialization.vulkan_graph_schema import (
+    Bool,
+    Double,
+    Int,
+)
 from executorch.backends.vulkan.vulkan_preprocess import apply_passes
 from executorch.exir import to_edge
 from executorch.exir.backend.utils import DelegateMappingBuilder
 from executorch.exir.passes import SpecPropPass
 
 
+class TestVkGraphBuilderScalarTensor(unittest.TestCase):
+    def test_scalar_cache_preserves_types_and_signed_zero(self):
+        program = torch.export.export(torch.nn.Identity(), (torch.ones(1),))
+        builder = VkGraphBuilder(
+            program, DelegateMappingBuilder(generated_identifiers=True)
+        )
+        scalars = (1.0, 1, True, 0.0, -0.0, 0, False)
+        expected = (
+            Double(1.0),
+            Int(1),
+            Bool(True),
+            Double(0.0),
+            Double(-0.0),
+            Int(0),
+            Bool(False),
+        )
+        ids = [builder.get_or_create_scalar_value(value) for value in scalars]
+        self.assertEqual(len(set(ids)), len(scalars))
+        for value, value_id, serialized in zip(scalars, ids, expected):
+            self.assertEqual(builder.get_or_create_scalar_value(value), value_id)
+            self.assertEqual(repr(builder.values[value_id].value), repr(serialized))
+
+
 class TestVkGraphBuilderInputIds(unittest.TestCase):
     """The serialized input list has to match the delegate call's arguments.