renderer: added support for instance step rates

src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp

@@ -135,15 +135,33 @@ Id EmitGetAttribute(EmitContext& ctx, IR::Attribute attr, u32 comp) {
     if (IR::IsParam(attr)) {
         const u32 index{u32(attr) - u32(IR::Attribute::Param0)};
         const auto& param{ctx.input_params.at(index)};
-        if (!ValidId(param.id)) {
+        if (param.buffer_handle < 0) {
-            // Attribute is disabled or varying component is not written
+            if (!ValidId(param.id)) {
-            return ctx.ConstF32(comp == 3 ? 1.0f : 0.0f);
+                // Attribute is disabled or varying component is not written
-        }
+                return ctx.ConstF32(comp == 3 ? 1.0f : 0.0f);
-        if (param.num_components > 1) {
+            }
-            const Id pointer{ctx.OpAccessChain(param.pointer_type, param.id, ctx.ConstU32(comp))};
+
-            return ctx.OpLoad(param.component_type, pointer);
+            if (param.num_components > 1) {
+                const Id pointer{
+                    ctx.OpAccessChain(param.pointer_type, param.id, ctx.ConstU32(comp))};
+                return ctx.OpLoad(param.component_type, pointer);
+            } else {
+                return ctx.OpLoad(param.component_type, param.id);
+            }
         } else {
-            return ctx.OpLoad(param.component_type, param.id);
+            const auto rate_idx = param.id.value == 0 ? ctx.u32_zero_value : ctx.u32_one_value;
+            const auto step_rate = ctx.OpLoad(
+                ctx.U32[1],
+                ctx.OpAccessChain(ctx.TypePointer(spv::StorageClass::PushConstant, ctx.U32[1]),
+                                  ctx.instance_step_rates, rate_idx));
+            const auto offset = ctx.OpIAdd(
+                ctx.U32[1],
+                ctx.OpIMul(
+                    ctx.U32[1],
+                    ctx.OpUDiv(ctx.U32[1], ctx.OpLoad(ctx.U32[1], ctx.instance_id), step_rate),
+                    ctx.ConstU32(param.num_components)),
+                ctx.ConstU32(comp));
+            return EmitReadConstBuffer(ctx, param.buffer_handle, offset);
         }
     }
     switch (attr) {

src/shader_recompiler/backend/spirv/spirv_emit_context.cpp

@@ -171,17 +171,47 @@ Id MakeDefaultValue(EmitContext& ctx, u32 default_value) {
 
 void EmitContext::DefineInputs(const Info& info) {
     switch (stage) {
-    case Stage::Vertex:
+    case Stage::Vertex: {
         vertex_index = DefineVariable(U32[1], spv::BuiltIn::VertexIndex, spv::StorageClass::Input);
         base_vertex = DefineVariable(U32[1], spv::BuiltIn::BaseVertex, spv::StorageClass::Input);
+        instance_id = DefineVariable(U32[1], spv::BuiltIn::InstanceIndex, spv::StorageClass::Input);
+
+        // Create push constants block for instance steps rates
+        const Id struct_type{Name(TypeStruct(U32[1], U32[1]), "instance_step_rates")};
+        Decorate(struct_type, spv::Decoration::Block);
+        MemberName(struct_type, 0, "sr0");
+        MemberName(struct_type, 1, "sr1");
+        MemberDecorate(struct_type, 0, spv::Decoration::Offset, 0U);
+        MemberDecorate(struct_type, 1, spv::Decoration::Offset, 4U);
+        instance_step_rates = DefineVar(struct_type, spv::StorageClass::PushConstant);
+        Name(instance_step_rates, "step_rates");
+        interfaces.push_back(instance_step_rates);
+
         for (const auto& input : info.vs_inputs) {
             const Id type{GetAttributeType(*this, input.fmt)};
-            const Id id{DefineInput(type, input.binding)};
+            if (input.instance_step_rate == Info::VsInput::InstanceIdType::OverStepRate0 ||
-            Name(id, fmt::format("vs_in_attr{}", input.binding));
+                input.instance_step_rate == Info::VsInput::InstanceIdType::OverStepRate1) {
-            input_params[input.binding] = GetAttributeInfo(input.fmt, id);
+
-            interfaces.push_back(id);
+                const u32 rate_idx =
+                    input.instance_step_rate == Info::VsInput::InstanceIdType::OverStepRate0 ? 0
+                                                                                             : 1;
+                // Note that we pass index rather than Id
+                input_params[input.binding] = {
+                    rate_idx, input_u32, U32[1], input.num_components, input.instance_data_buf,
+                };
+            } else {
+                Id id{DefineInput(type, input.binding)};
+                if (input.instance_step_rate == Info::VsInput::InstanceIdType::Plain) {
+                    Name(id, fmt::format("vs_instance_attr{}", input.binding));
+                } else {
+                    Name(id, fmt::format("vs_in_attr{}", input.binding));
+                }
+                input_params[input.binding] = GetAttributeInfo(input.fmt, id);
+                interfaces.push_back(id);
+            }
         }
         break;
+    }
     case Stage::Fragment:
         if (info.uses_group_quad) {
             subgroup_local_invocation_id = DefineVariable(
@@ -276,7 +306,10 @@ void EmitContext::DefineBuffers(const Info& info) {
         if (std::ranges::find(type_ids, record_array_type.value, &Id::value) == type_ids.end()) {
             Decorate(record_array_type, spv::Decoration::ArrayStride, 4);
             const auto name =
-                fmt::format("{}_cbuf_block_{}{}", stage, 'f', sizeof(float) * CHAR_BIT);
+                buffer.is_instance_data
+                    ? fmt::format("{}_instance_data{}_{}{}", stage, i, 'f',
+                                  sizeof(float) * CHAR_BIT)
+                    : fmt::format("{}_cbuf_block_{}{}", stage, 'f', sizeof(float) * CHAR_BIT);
             Name(struct_type, name);
             Decorate(struct_type, spv::Decoration::Block);
             MemberName(struct_type, 0, "data");

src/shader_recompiler/backend/spirv/spirv_emit_context.h

@@ -165,6 +165,8 @@ public:
 
     Id output_position{};
     Id vertex_index{};
+    Id instance_id{};
+    Id instance_step_rates{};
     Id base_vertex{};
     Id frag_coord{};
     Id front_facing{};
@@ -214,6 +216,7 @@ public:
         Id pointer_type;
         Id component_type;
         u32 num_components;
+        s32 buffer_handle{-1};
     };
     std::array<SpirvAttribute, 32> input_params{};
     std::array<SpirvAttribute, 32> output_params{};

src/shader_recompiler/frontend/translate/translate.cpp

@@ -235,9 +235,21 @@ void Translator::EmitFetch(const GcnInst& inst) {
             ir.SetVectorReg(dst_reg++, comp);
         }
 
-        if (attrib.instance_data == 2 || attrib.instance_data == 3) {
+        // In case of programmable step rates we need to fallback to instance data pulling in
-            LOG_WARNING(Render_Recompiler, "Unsupported instance step rate = {}",
+        // shader, so VBs should be bound as regular data buffers
-                        attrib.instance_data);
+        s32 instance_buf_handle = -1;
+        const auto step_rate = static_cast<Info::VsInput::InstanceIdType>(attrib.instance_data);
+        if (step_rate == Info::VsInput::OverStepRate0 ||
+            step_rate == Info::VsInput::OverStepRate1) {
+            info.buffers.push_back({
+                .sgpr_base = attrib.sgpr_base,
+                .dword_offset = attrib.dword_offset,
+                .stride = buffer.GetStride(),
+                .num_records = buffer.num_records,
+                .used_types = IR::Type::F32,
+                .is_instance_data = true,
+            });
+            instance_buf_handle = s32(info.buffers.size() - 1);
         }
 
         const u32 num_components = AmdGpu::NumComponents(buffer.GetDataFmt());
@@ -247,7 +259,8 @@ void Translator::EmitFetch(const GcnInst& inst) {
             .num_components = std::min<u16>(attrib.num_elements, num_components),
             .sgpr_base = attrib.sgpr_base,
             .dword_offset = attrib.dword_offset,
-            .instance_step_rate = static_cast<Info::VsInput::InstanceIdType>(attrib.instance_data),
+            .instance_step_rate = step_rate,
+            .instance_data_buf = instance_buf_handle,
         });
     }
 }

src/shader_recompiler/runtime_info.h

@@ -77,7 +77,8 @@ struct BufferResource {
     u32 num_records;
     IR::Type used_types;
     AmdGpu::Buffer inline_cbuf;
-    bool is_storage;
+    bool is_storage{false};
+    bool is_instance_data{false};
 
     constexpr AmdGpu::Buffer GetVsharp(const Info& info) const noexcept;
 };
@@ -116,6 +117,7 @@ struct Info {
         u8 sgpr_base;
         u8 dword_offset;
         InstanceIdType instance_step_rate;
+        s32 instance_data_buf;
     };
     boost::container::static_vector<VsInput, 32> vs_inputs{};
 

src/video_core/amdgpu/liverpool.h

@@ -887,7 +887,10 @@ struct Liverpool {
             IndexBufferType index_buffer_type;
             INSERT_PADDING_WORDS(0xA2A1 - 0xA29E - 2);
             u32 enable_primitive_id;
-            INSERT_PADDING_WORDS(0xA2DF - 0xA2A1 - 1);
+            INSERT_PADDING_WORDS(0xA2A8 - 0xA2A1 - 1);
+            u32 vgt_instance_step_rate_0;
+            u32 vgt_instance_step_rate_1;
+            INSERT_PADDING_WORDS(0xA2DF - 0xA2A9 - 1);
             PolygonOffset poly_offset;
             INSERT_PADDING_WORDS(0xA2F8 - 0xA2DF - 5);
             AaConfig aa_config;
@@ -1046,6 +1049,8 @@ static_assert(GFX6_3D_REG_INDEX(vs_output_control) == 0xA207);
 static_assert(GFX6_3D_REG_INDEX(index_size) == 0xA29D);
 static_assert(GFX6_3D_REG_INDEX(index_buffer_type) == 0xA29F);
 static_assert(GFX6_3D_REG_INDEX(enable_primitive_id) == 0xA2A1);
+static_assert(GFX6_3D_REG_INDEX(vgt_instance_step_rate_0) == 0xA2A8);
+static_assert(GFX6_3D_REG_INDEX(vgt_instance_step_rate_1) == 0xA2A9);
 static_assert(GFX6_3D_REG_INDEX(poly_offset) == 0xA2DF);
 static_assert(GFX6_3D_REG_INDEX(aa_config) == 0xA2F8);
 static_assert(GFX6_3D_REG_INDEX(color_buffers[0].base_address) == 0xA318);

src/video_core/renderer_vulkan/vk_graphics_pipeline.cpp

@@ -30,12 +30,19 @@ GraphicsPipeline::GraphicsPipeline(const Instance& instance_, Scheduler& schedul
         stages[i] = *infos[i];
     }
     BuildDescSetLayout();
+
+    const vk::PushConstantRange push_constants = {
+        .stageFlags = vk::ShaderStageFlagBits::eVertex,
+        .offset = 0,
+        .size = 2 * sizeof(u32),
+    };
+
     const vk::DescriptorSetLayout set_layout = *desc_layout;
     const vk::PipelineLayoutCreateInfo layout_info = {
         .setLayoutCount = 1U,
         .pSetLayouts = &set_layout,
-        .pushConstantRangeCount = 0,
+        .pushConstantRangeCount = 1,
-        .pPushConstantRanges = nullptr,
+        .pPushConstantRanges = &push_constants,
     };
     pipeline_layout = instance.GetDevice().createPipelineLayoutUnique(layout_info);
 
@@ -43,6 +50,12 @@ GraphicsPipeline::GraphicsPipeline(const Instance& instance_, Scheduler& schedul
     boost::container::static_vector<vk::VertexInputAttributeDescription, 32> attributes;
     const auto& vs_info = stages[0];
     for (const auto& input : vs_info.vs_inputs) {
+        if (input.instance_step_rate == Shader::Info::VsInput::InstanceIdType::OverStepRate0 ||
+            input.instance_step_rate == Shader::Info::VsInput::InstanceIdType::OverStepRate1) {
+            // Skip attribute binding as the data will be pulled by shader
+            continue;
+        }
+
         const auto buffer = vs_info.ReadUd<AmdGpu::Buffer>(input.sgpr_base, input.dword_offset);
         attributes.push_back({
             .location = input.binding,
@@ -420,6 +433,11 @@ void GraphicsPipeline::BindVertexBuffers(StreamBuffer& staging) const {
     // Calculate buffers memory overlaps
     boost::container::static_vector<BufferRange, MaxVertexBufferCount> ranges{};
     for (const auto& input : vs_info.vs_inputs) {
+        if (input.instance_step_rate == Shader::Info::VsInput::InstanceIdType::OverStepRate0 ||
+            input.instance_step_rate == Shader::Info::VsInput::InstanceIdType::OverStepRate1) {
+            continue;
+        }
+
         const auto& buffer = vs_info.ReadUd<AmdGpu::Buffer>(input.sgpr_base, input.dword_offset);
         if (buffer.GetSize() == 0) {
             continue;

src/video_core/renderer_vulkan/vk_graphics_pipeline.h

@@ -67,20 +67,24 @@ public:
     void BindResources(Core::MemoryManager* memory, StreamBuffer& staging,
                        VideoCore::TextureCache& texture_cache) const;
 
-    [[nodiscard]] vk::Pipeline Handle() const noexcept {
+    vk::Pipeline Handle() const noexcept {
         return *pipeline;
     }
 
-    [[nodiscard]] bool IsEmbeddedVs() const noexcept {
+    vk::PipelineLayout GetLayout() const {
+        return *pipeline_layout;
+    }
+
+    bool IsEmbeddedVs() const noexcept {
         static constexpr size_t EmbeddedVsHash = 0x9b2da5cf47f8c29f;
         return key.stage_hashes[0] == EmbeddedVsHash;
     }
 
-    [[nodiscard]] auto GetWriteMasks() const {
+    auto GetWriteMasks() const {
         return key.write_masks;
     }
 
-    [[nodiscard]] bool IsDepthEnabled() const {
+    bool IsDepthEnabled() const {
         return key.depth.depth_enable.Value();
     }
 

src/video_core/renderer_vulkan/vk_rasterizer.cpp

@@ -54,6 +54,13 @@ void Rasterizer::Draw(bool is_indexed, u32 index_offset) {
     UpdateDynamicState(*pipeline);
 
     cmdbuf.bindPipeline(vk::PipelineBindPoint::eGraphics, pipeline->Handle());
+
+    const u32 step_rates[] = {
+        regs.vgt_instance_step_rate_0,
+        regs.vgt_instance_step_rate_1,
+    };
+    cmdbuf.pushConstants(pipeline->GetLayout(), vk::ShaderStageFlagBits::eVertex, 0u,
+                         sizeof(step_rates), &step_rates);
     if (is_indexed) {
         cmdbuf.drawIndexed(num_indices, regs.num_instances.NumInstances(), 0, 0, 0);
     } else {