Add WGSL test for buffer pointers

tests/in/buffer-pointer.param.ron

@@ -0,0 +1,6 @@
+(
+	god_mode: true,
+	spv: (
+		version: (1, 5),
+	),
+)

tests/in/buffer-pointer.wgsl

@@ -0,0 +1,28 @@
+struct OtherStruct {
+    data: vec2<f32>,
+}
+
+struct MyBuffer {
+    data: vec4<f32>,
+    sub_buffer: ptr<buffer, OtherStruct, 8>, // Custom alignment = 8
+}
+
+// TODO: recursive references
+// struct MyBuffer2 {
+//     data: f32,
+//     next: ptr<buffer, MyBuffer2>,
+// }
+
+struct PushConstants {
+    buf1: ptr<buffer, MyBuffer>,    // Default alignment = 16
+    four_bytes: u32,                // Test struct member offset
+    buf2: ptr<buffer, MyBuffer, 4>, // Custom alignment = 4
+}
+var<push_constant> pc: PushConstants;
+
+@fragment
+fn main() -> @location(0) vec4<f32> {
+    var d1 = (*pc.buf1).data;
+    var d2 = (*(*pc.buf2).sub_buffer).data;
+    return d1 + vec4<f32>(d2, 0.0, 0.0);
+}

tests/out/spv/buffer-pointer.spvasm

@@ -0,0 +1,75 @@
+; SPIR-V
+; Version: 1.5
+; Generator: rspirv
+; Bound: 52
+OpCapability Shader
+OpCapability PhysicalStorageBufferAddresses
+%1 = OpExtInstImport "GLSL.std.450"
+OpMemoryModel PhysicalStorageBuffer64 GLSL450
+OpEntryPoint Fragment %24 "main" %22 %12
+OpExecutionMode %24 OriginUpperLeft
+OpMemberDecorate %5 0 Offset 0
+OpMemberDecorate %8 0 Offset 0
+OpMemberDecorate %8 1 Offset 16
+OpMemberDecorate %11 0 Offset 0
+OpMemberDecorate %11 1 Offset 8
+OpMemberDecorate %11 2 Offset 16
+OpDecorate %13 Block
+OpMemberDecorate %13 0 Offset 0
+OpDecorate %22 Location 0
+%2 = OpTypeVoid
+%4 = OpTypeFloat 32
+%3 = OpTypeVector %4 2
+%5 = OpTypeStruct %3
+%6 = OpTypeVector %4 4
+%7 = OpTypePointer PhysicalStorageBuffer %5
+%8 = OpTypeStruct %6 %7
+%9 = OpTypePointer PhysicalStorageBuffer %8
+%10 = OpTypeInt 32 0
+%11 = OpTypeStruct %9 %10 %9
+%13 = OpTypeStruct %11
+%14 = OpTypePointer PushConstant %13
+%12 = OpVariable  %14  PushConstant
+%16 = OpTypePointer Function %6
+%17 = OpConstantNull  %6
+%19 = OpTypePointer Function %3
+%20 = OpConstantNull  %3
+%23 = OpTypePointer Output %6
+%22 = OpVariable  %23  Output
+%25 = OpTypeFunction %2
+%26 = OpTypePointer PushConstant %11
+%27 = OpConstant  %10  0
+%29 = OpConstant  %4  0.0
+%31 = OpTypePointer PushConstant %9
+%34 = OpTypePointer PhysicalStorageBuffer %6
+%37 = OpTypePointer PushConstant %9
+%38 = OpConstant  %10  2
+%41 = OpTypePointer PhysicalStorageBuffer %7
+%42 = OpConstant  %10  1
+%45 = OpTypePointer PhysicalStorageBuffer %3
+%24 = OpFunction  %2  None %25
+%21 = OpLabel
+%15 = OpVariable  %16  Function %17
+%18 = OpVariable  %19  Function %20
+%28 = OpAccessChain  %26  %12 %27
+OpBranch %30
+%30 = OpLabel
+%32 = OpAccessChain  %31  %28 %27
+%33 = OpLoad  %9  %32
+%35 = OpAccessChain  %34  %33 %27
+%36 = OpLoad  %6  %35 Aligned 16
+OpStore %15 %36
+%39 = OpAccessChain  %37  %28 %38
+%40 = OpLoad  %9  %39
+%43 = OpAccessChain  %41  %40 %42
+%44 = OpLoad  %7  %43 Aligned 4
+%46 = OpAccessChain  %45  %44 %27
+%47 = OpLoad  %3  %46 Aligned 8
+OpStore %18 %47
+%48 = OpLoad  %6  %15
+%49 = OpLoad  %3  %18
+%50 = OpCompositeConstruct  %6  %49 %29 %29
+%51 = OpFAdd  %6  %48 %50
+OpStore %22 %51
+OpReturn
+OpFunctionEnd

tests/snapshots.rs

@@ -615,6 +615,7 @@ fn convert_wgsl() {
             "constructors",
             Targets::SPIRV | Targets::METAL | Targets::GLSL | Targets::HLSL | Targets::WGSL,
         ),
+        ("buffer-pointer", Targets::SPIRV),
     ];
 
     for &(name, targets) in inputs.iter() {