Defer `IRCastStorageToLogicalDeref` in lowerBufferElementType pass. (#8668)

Fix a regression on metal test.

In `lowerBufferElementTypeToStorageType` pass, not only we want to defer
an argument that is `CastStorageToLogical` to the callee, but also apply
the same defer logic to `CastStorageToLogicalDeref` as well.

Because `CastStorageToLogicalDeref` will appear as argumnet if
`lowerBufferElementTypeToStorageType` is run before we apply the
`in->borrow` transformation pass, which is the case for metal parameter
block legalization.

1 files changed, 34 insertions, 0 deletions

diff --git a/tests/metal/sampler-array.slang b/tests/metal/sampler-array.slang
new file mode 100644
index 000000000..65476543e
--- /dev/null
+++ b/tests/metal/sampler-array.slang
@@ -0,0 +1,34 @@
+//TEST:SIMPLE(filecheck=MTL): -target metal -stage compute -entry computeMain
+//TEST:SIMPLE(filecheck=LIB): -target metallib -stage compute -entry computeMain
+
+// MTL: float S1_test{{.*}}(const S1_default{{.*}} constant* this{{.*}}
+// LIB: computeMain
+
+struct S1
+{
+    Texture2D tex[32];
+    SamplerState samplers[32];
+    float data;
+    float test(int i)
+    {
+        return tex[i].SampleLevel(samplers[i], float2(0.0, 0.0), 0.0).x + data;
+    }
+}
+
+struct S0
+{
+    float data;
+    RaytracingAccelerationStructure acc;
+    ParameterBlock<S1> s;
+}
+
+ParameterBlock<S0> g;
+RWStructuredBuffer<float> buffer;
+
+[shader("compute")]
+[numthreads(1,1,1)]
+void computeMain(
+    uint3 sv_dispatchThreadID : SV_DispatchThreadID)
+{
+    buffer[0] = g.data * g.s.test(sv_dispatchThreadID.x);
+}