From 8d46517fba561ebdad848a03a6709ea295979c81 Mon Sep 17 00:00:00 2001
From: Mergen Nachin <mnachin@meta.com>
Date: Tue, 29 Sep 2026 11:02:07 -0400
Subject: [PATCH] [INITIAL] Recreate the Vulkan transformer and conformance
 stack with ghstack

[ghstack-poisoned]
---
 backends/vulkan/op_registry.py              |  2 +-
 backends/vulkan/test/test_vulkan_dynamic.py | 69 +++++++++++++++++++++
 2 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/backends/vulkan/op_registry.py b/backends/vulkan/op_registry.py
index 1bdff20f05c..efe9ca7d81f 100644
--- a/backends/vulkan/op_registry.py
+++ b/backends/vulkan/op_registry.py
@@ -1367,7 +1367,7 @@ def register_expand_copy():
     return OpFeatures(
         inputs_storage=utils.ANY_STORAGE,
         inputs_dtypes=utils.FP_INT_BOOL_T,
-        supports_resize=False,
+        supports_resize=True,
         supports_highdim=True,
     )
 
diff --git a/backends/vulkan/test/test_vulkan_dynamic.py b/backends/vulkan/test/test_vulkan_dynamic.py
index c9292d916c1..7b760cd5b2f 100644
--- a/backends/vulkan/test/test_vulkan_dynamic.py
+++ b/backends/vulkan/test/test_vulkan_dynamic.py
@@ -50,6 +50,25 @@ def _vulkan_graphs(edge):
     ]
 
 
+class TransformerBlock(torch.nn.Module):
+    def __init__(self, sdpa):
+        super().__init__()
+        self.sdpa = sdpa
+        self.qkv = torch.nn.Linear(64, 192)
+        self.ff = torch.nn.Linear(64, 64)
+
+    def forward(self, x, lengths):
+        b, s, _ = x.shape
+        mask = (torch.arange(s)[None, :] < lengths[:, None])[:, None, None, :]
+        q, k, v = self.qkv(x).view(b, s, 3, 2, 32).permute(2, 0, 3, 1, 4)
+        if self.sdpa:
+            y = F.scaled_dot_product_attention(q, k, v, attn_mask=mask)
+        else:
+            bias = torch.where(mask, 0.0, -torch.inf)
+            y = torch.softmax(q @ k.transpose(-1, -2) * 32**-0.5 + bias, -1) @ v
+        return F.gelu(self.ff(y.transpose(1, 2).reshape(b, s, 64)))
+
+
 class ConstantMask(torch.nn.Module):
     def __init__(self):
         super().__init__()
@@ -144,6 +163,36 @@ def _run(
                             )
                         )
 
+    def test_partition_transformer(self):
+        for sdpa in (False, True):
+            with self.subTest(sdpa=sdpa):
+                self._lower(
+                    TransformerBlock(sdpa),
+                    (torch.randn(1, 16, 64), torch.tensor([16])),
+                    ({1: Dim("s", min=2, max=1000)}, {}),
+                )
+
+    def test_dynamic_transformer(self):
+        torch.manual_seed(0)
+        for sdpa in (False, True):
+            for storage in (VkStorageType.TEXTURE_3D, VkStorageType.BUFFER):
+                with self.subTest(sdpa=sdpa, storage=storage):
+                    model = TransformerBlock(sdpa).eval()
+                    inputs = [
+                        (torch.randn(1, s, 64), torch.tensor([length]))
+                        for s, length in (
+                            (16, 16),
+                            (7, 4),
+                            (31, 23),
+                            (2, 1),
+                            (16, 0 if sdpa else 5),
+                        )
+                    ]
+                    edge = self._lower(
+                        model, inputs[0], ({1: Dim("s", min=2, max=32)}, {}), storage
+                    )
+                    self._run(edge, model, inputs)
+
     def test_partition_any_unsupported_inputs(self):
         class AnyDim(torch.nn.Module):
             def forward(self, x):
@@ -249,6 +298,26 @@ def forward(self, x):
                 edge = self._lower(model, inputs[0])
                 self._run(edge, model, inputs, atol=0, rtol=0)
 
+    def test_dynamic_expand(self):
+        class Expand(torch.nn.Module):
+            def __init__(self):
+                super().__init__()
+                self.register_buffer(
+                    "offset", torch.arange(4, dtype=torch.float32)[None, :]
+                )
+
+            def forward(self, x):
+                return x.expand(2, x.shape[1], 4) + self.offset.expand(2, 4)[:, None, :]
+
+        for storage in (VkStorageType.TEXTURE_3D, VkStorageType.BUFFER):
+            with self.subTest(storage=storage):
+                model = Expand()
+                inputs = [(torch.randn(1, s, 1),) for s in (16, 3, 31, 2, 16)]
+                edge = self._lower(
+                    model, inputs[0], ({1: Dim("s", min=2, max=32)},), storage
+                )
+                self._run(edge, model, inputs, atol=0, rtol=0)
+
     def test_dynamic_full(self):
         class Full(torch.nn.Module):
             def forward(self, x):