Port remaining SampledTexture2D tests (#1075)

Part of microsoft/DirectXShaderCompiler#7979

The tests are originally from `Texture2D`. Verified every test ported
for `SampledTexture2D`

Author: luciechoi

test/Feature/Vk.SampledTextures/Vk.SampledTexture2D/Vk.SampledTexture2D.CalculateLevelOfDetail.test.yaml

@@ -0,0 +1,131 @@
+#--- source.hlsl
+struct VSInput {
+  float3 Pos : POSITION;
+};
+
+struct VSOutput {
+  float4 Pos : SV_POSITION;
+};
+
+VSOutput mainVS(VSInput input) {
+  VSOutput output;
+  output.Pos = float4(input.Pos, 1.0f);
+  return output;
+}
+
+[[vk::binding(0, 0)]] vk::SampledTexture2D<float4> SampledTex : register(s0);
+[[vk::binding(1, 0)]] RWBuffer<float> Out : register(u0);
+
+float4 mainPS(VSOutput input) : SV_Target {
+  // Use SV_Position (pixel coordinates) to simulate the grid logic.
+  // Input position is [-1, 1], mapped to viewport 2x2.
+  // Pixel centers will be at (0.5, 0.5), (1.5, 0.5), etc.
+  uint2 GTid = (uint2)input.Pos.xy;
+
+  // Case 1: Derivative = 0.5. Texture Size = 4.
+  // LOD = log2(0.5 * 4) = 1.0
+  float2 uv0 = 0.25 + float2(GTid.xy) * 0.5;
+
+  // Case 2: Derivative = 2.0. Texture Size = 4.
+  // LOD = log2(2.0 * 4) = 3.0.
+  // Note: Since the texture has 3 mip levels (0, 1, 2),
+  // the clamped LOD will be 2.0.
+  float2 uv1 = 0.25 + float2(GTid.xy) * 2.0;
+
+  float lod0 = SampledTex.CalculateLevelOfDetail(uv0);
+  float lod1 = SampledTex.CalculateLevelOfDetail(uv1);
+  float lod2 = SampledTex.CalculateLevelOfDetailUnclamped(uv0);
+  float lod3 = SampledTex.CalculateLevelOfDetailUnclamped(uv1);
+
+  if (all(GTid.xy == 0)) {
+    Out[0] = lod0;
+    Out[1] = lod1;
+    Out[2] = lod2;
+    Out[3] = lod3;
+  }
+  return float4(0, 0, 0, 0);
+}
+
+//--- pipeline.yaml
+---
+Shaders:
+  - Stage: Vertex
+    Entry: mainVS
+  - Stage: Pixel
+    Entry: mainPS
+
+Buffers:
+  - Name: SampledTex
+    Format: Float32
+    Channels: 4
+    OutputProps: { Width: 4, Height: 4, Depth: 1, MipLevels: 3 }
+    FillSize: 336 # (16+4+1)*16
+
+  - Name: Out
+    Format: Float32
+    Channels: 1
+    FillSize: 16 # 4 * sizeof(float)
+
+  - Name: Expected
+    Format: Float32
+    Channels: 1
+    Data: [ 1.0, 2.0, 1.0, 3.0 ]
+
+  - Name: RT
+    Format: Float32
+    Channels: 4
+    FillSize: 64
+    OutputProps: { Width: 2, Height: 2, Depth: 1 }
+
+  - Name: VB
+    Format: Float32
+    Channels: 3
+    Data: [-1.0, -1.0, 0.0,
+            3.0, -1.0, 0.0,
+           -1.0,  3.0, 0.0]
+
+Bindings:
+  VertexBuffer: VB
+  VertexAttributes:
+    - Format: Float32
+      Channels: 3
+      Offset: 0
+      Name: POSITION
+  RenderTarget: RT
+
+Samplers:
+  - Name: SampledTex
+    MinFilter: Linear
+    MagFilter: Linear
+    Address: Clamp
+
+DescriptorSets:
+  - Resources:
+    - Name: SampledTex
+      Kind: SampledTexture2D
+      DirectXBinding: { Register: 0, Space: 0 }
+      VulkanBinding: { Binding: 0 }
+    - Name: Out
+      Kind: RWBuffer
+      DirectXBinding: { Register: 0, Space: 0 }
+      VulkanBinding: { Binding: 1 }
+
+Results:
+  - Result: LODTest
+    Rule: BufferFloatULP
+    Actual: Out
+    Expected: Expected
+    ULPT: 1
+...
+#--- end
+
+# Unimplemented: This is a Vulkan specific feature.
+# UNSUPPORTED: !Vulkan
+
+# Unimplemented: https://github.com/llvm/llvm-project/issues/181910
+# XFAIL: Clang && Vulkan
+
+# RUN: split-file %s %t
+# RUN: %dxc_target -T vs_6_6 -E mainVS -Fo %t-vs.o %t/source.hlsl
+# RUN: %dxc_target -T ps_6_6 -E mainPS -Fo %t-ps.o %t/source.hlsl
+# RUN: %offloader %t/pipeline.yaml %t-vs.o %t-ps.o

test/Feature/Vk.SampledTextures/Vk.SampledTexture2D/Vk.SampledTexture2D.Gather.test.yaml

@@ -0,0 +1,133 @@
+#--- source.hlsl
+[[vk::binding(0, 0)]] vk::SampledTexture2D<float4> SampledTexClamp : register(s0);
+[[vk::binding(1, 0)]] vk::SampledTexture2D<float4> SampledTexRepeat : register(s1);
+[[vk::binding(2, 0)]] RWBuffer<float4> Out : register(u0);
+
+[numthreads(1, 1, 1)]
+void main() {
+  // Gather at (0.5, 0.5) on a 2x2 texture.
+  // Texels used: (0,0), (1,0), (0,1), (1,1).
+  // Gather returns a float4 containing the Red component of:
+  // [ (0,1), (1,1), (1,0), (0,0) ]
+  Out[0] = SampledTexClamp.Gather(float2(0.5, 0.5));
+
+  // Also test GatherRed explicitly (equivalent to Gather)
+  Out[1] = SampledTexClamp.GatherRed(float2(0.5, 0.5));
+
+  // Also test GatherGreen
+  Out[2] = SampledTexClamp.GatherGreen(float2(0.5, 0.5));
+
+  // Also test GatherBlue
+  Out[3] = SampledTexClamp.GatherBlue(float2(0.5, 0.5));
+
+  // Also test GatherAlpha
+  Out[4] = SampledTexClamp.GatherAlpha(float2(0.5, 0.5));
+
+  // Test sampler usage for all channels.
+  float2 uv_outside = float2(1.5, 1.5);
+
+  // Red
+  Out[5] = SampledTexClamp.GatherRed(uv_outside);
+  Out[6] = SampledTexRepeat.GatherRed(uv_outside);
+
+  // Green
+  Out[7] = SampledTexClamp.GatherGreen(uv_outside);
+  Out[8] = SampledTexRepeat.GatherGreen(uv_outside);
+
+  // Blue
+  Out[9] = SampledTexClamp.GatherBlue(uv_outside);
+  Out[10] = SampledTexRepeat.GatherBlue(uv_outside);
+
+  // Alpha
+  Out[11] = SampledTexClamp.GatherAlpha(uv_outside);
+  Out[12] = SampledTexRepeat.GatherAlpha(uv_outside);
+}
+
+//--- pipeline.yaml
+---
+Shaders:
+  - Stage: Compute
+    Entry: main
+    DispatchSize: [1, 1, 1]
+
+Buffers:
+  - Name: SampledTexClamp
+    Format: Float32
+    Channels: 4
+    OutputProps: { Width: 2, Height: 2, Depth: 1 }
+    Data: [ 1.0, 0.0, 0.0, 1.0,  # Red   (0,0) -> R=1, G=0, B=0, A=1
+            0.0, 1.0, 0.0, 1.0,  # Green (1,0) -> R=0, G=1, B=0, A=1
+            0.0, 0.0, 1.0, 1.0,  # Blue  (0,1) -> R=0, G=0, B=1, A=1
+            1.0, 1.0, 1.0, 0.5 ] # White (1,1) -> R=1, G=1, B=1, A=0.5
+
+  - Name: SampledTexRepeat
+    Format: Float32
+    Channels: 4
+    OutputProps: { Width: 2, Height: 2, Depth: 1 }
+    Data: [ 1.0, 0.0, 0.0, 1.0,  # Red   (0,0) -> R=1, G=0, B=0, A=1
+            0.0, 1.0, 0.0, 1.0,  # Green (1,0) -> R=0, G=1, B=0, A=1
+            0.0, 0.0, 1.0, 1.0,  # Blue  (0,1) -> R=0, G=0, B=1, A=1
+            1.0, 1.0, 1.0, 0.5 ] # White (1,1) -> R=1, G=1, B=1, A=0.5
+
+  - Name: Out
+    Format: Float32
+    Channels: 4
+    FillSize: 208 # 13 * sizeof(float4)
+
+  - Name: Expected
+    Format: Float32
+    Channels: 4
+    Data: [ 0.0, 1.0, 0.0, 1.0,  # 0: Gather (Red) (0.5, 0.5)
+            0.0, 1.0, 0.0, 1.0,  # 1: GatherRed (0.5, 0.5)
+            0.0, 1.0, 1.0, 0.0,  # 2: GatherGreen (0.5, 0.5)
+            1.0, 1.0, 0.0, 0.0,  # 3: GatherBlue (0.5, 0.5)
+            1.0, 0.5, 1.0, 1.0,  # 4: GatherAlpha (0.5, 0.5)
+            1.0, 1.0, 1.0, 1.0,  # 5: Red Clamp (1.5, 1.5) -> (1,1) everywhere
+            0.0, 1.0, 0.0, 1.0,  # 6: Red Repeat (1.5, 1.5) -> same as (0.5, 0.5)
+            1.0, 1.0, 1.0, 1.0,  # 7: Green Clamp (1.5, 1.5)
+            0.0, 1.0, 1.0, 0.0,  # 8: Green Repeat (1.5, 1.5)
+            1.0, 1.0, 1.0, 1.0,  # 9: Blue Clamp (1.5, 1.5)
+            1.0, 1.0, 0.0, 0.0,  # 10: Blue Repeat (1.5, 1.5)
+            0.5, 0.5, 0.5, 0.5,  # 11: Alpha Clamp (1.5, 1.5)
+            1.0, 0.5, 1.0, 1.0 ] # 12: Alpha Repeat (1.5, 1.5)
+
+Samplers:
+  - Name: SampledTexClamp
+    MinFilter: Linear
+    MagFilter: Linear
+    Address: Clamp
+  - Name: SampledTexRepeat
+    Address: Repeat
+
+DescriptorSets:
+  - Resources:
+    - Name: SampledTexClamp
+      Kind: SampledTexture2D
+      DirectXBinding: { Register: 0, Space: 0 }
+      VulkanBinding: { Binding: 0 }
+    - Name: SampledTexRepeat
+      Kind: SampledTexture2D
+      DirectXBinding: { Register: 1, Space: 0 }
+      VulkanBinding: { Binding: 1 }
+    - Name: Out
+      Kind: RWBuffer
+      DirectXBinding: { Register: 0, Space: 0 }
+      VulkanBinding: { Binding: 2 }
+
+Results:
+  - Result: GatherTest
+    Rule: BufferExact
+    Actual: Out
+    Expected: Expected
+...
+#--- end
+
+# Unimplemented: This is a Vulkan specific feature.
+# UNSUPPORTED: !Vulkan
+
+# Unimplemented: https://github.com/llvm/llvm-project/issues/181910
+# XFAIL: Clang && Vulkan
+
+# RUN: split-file %s %t
+# RUN: %dxc_target -T cs_6_0 -Fo %t.o %t/source.hlsl
+# RUN: %offloader %t/pipeline.yaml %t.o