shader: Implement indexed Position and ClipDistances

src/shader_recompiler/backend/spirv/emit_context.cpp

@@ -327,6 +327,10 @@ void EmitContext::DefineAttributeMemAccess(const Info& info) {
         const Id compare_index{OpShiftRightLogical(U32[1], base_index, Constant(U32[1], 2U))};
         std::vector<Sirit::Literal> literals;
         std::vector<Id> labels;
+        if (info.loads_position) {
+            literals.push_back(static_cast<u32>(IR::Attribute::PositionX) >> 2);
+            labels.push_back(OpLabel());
+        }
         const u32 base_attribute_value = static_cast<u32>(IR::Attribute::Generic0X) >> 2;
         for (u32 i = 0; i < info.input_generics.size(); i++) {
             if (!info.input_generics[i].used) {
@@ -340,6 +344,12 @@ void EmitContext::DefineAttributeMemAccess(const Info& info) {
         AddLabel(default_label);
         OpReturnValue(Constant(F32[1], 0.0f));
         size_t label_index = 0;
+        if (info.loads_position) {
+            AddLabel(labels[label_index]);
+            const Id result{OpLoad(F32[1], OpAccessChain(input_f32, input_position, masked_index))};
+            OpReturnValue(result);
+            label_index++;
+        }
         for (u32 i = 0; i < info.input_generics.size(); i++) {
             if (!info.input_generics[i].used) {
                 continue;
@@ -377,6 +387,10 @@ void EmitContext::DefineAttributeMemAccess(const Info& info) {
         const Id compare_index{OpShiftRightLogical(U32[1], base_index, Constant(U32[1], 2U))};
         std::vector<Sirit::Literal> literals;
         std::vector<Id> labels;
+        if (info.stores_position) {
+            literals.push_back(static_cast<u32>(IR::Attribute::PositionX) >> 2);
+            labels.push_back(OpLabel());
+        }
         const u32 base_attribute_value = static_cast<u32>(IR::Attribute::Generic0X) >> 2;
         for (u32 i = 0; i < info.stores_generics.size(); i++) {
             if (!info.stores_generics[i]) {
@@ -385,11 +399,24 @@ void EmitContext::DefineAttributeMemAccess(const Info& info) {
             literals.push_back(base_attribute_value + i);
             labels.push_back(OpLabel());
         }
+        if (info.stores_clip_distance) {
+            literals.push_back(static_cast<u32>(IR::Attribute::ClipDistance0) >> 2);
+            labels.push_back(OpLabel());
+            literals.push_back(static_cast<u32>(IR::Attribute::ClipDistance4) >> 2);
+            labels.push_back(OpLabel());
+        }
         OpSelectionMerge(end_block, spv::SelectionControlMask::MaskNone);
         OpSwitch(compare_index, default_label, literals, labels);
         AddLabel(default_label);
         OpReturn();
         size_t label_index = 0;
+        if (info.stores_position) {
+            AddLabel(labels[label_index]);
+            const Id pointer{OpAccessChain(output_f32, output_position, masked_index)};
+            OpStore(pointer, store_value);
+            OpReturn();
+            label_index++;
+        }
         for (u32 i = 0; i < info.stores_generics.size(); i++) {
             if (!info.stores_generics[i]) {
                 continue;
@@ -401,6 +428,19 @@ void EmitContext::DefineAttributeMemAccess(const Info& info) {
             OpReturn();
             label_index++;
         }
+        if (info.stores_clip_distance) {
+            AddLabel(labels[label_index]);
+            const Id pointer{OpAccessChain(output_f32, clip_distances, masked_index)};
+            OpStore(pointer, store_value);
+            OpReturn();
+            label_index++;
+            AddLabel(labels[label_index]);
+            const Id fixed_index{OpIAdd(U32[1], masked_index, Constant(U32[1], 4))};
+            const Id pointer2{OpAccessChain(output_f32, clip_distances, fixed_index)};
+            OpStore(pointer2, store_value);
+            OpReturn();
+            label_index++;
+        }
         AddLabel(end_block);
         OpUnreachable();
         OpFunctionEnd();

src/shader_recompiler/ir_opt/collect_shader_info_pass.cpp

@@ -517,22 +517,32 @@ void GatherInfoFromHeader(Environment& env, Info& info) {
     }
     const auto& header = env.SPH();
     if (stage == Stage::Fragment) {
+        if (!info.loads_indexed_attributes) {
+            return;
+        }
         for (size_t i = 0; i < info.input_generics.size(); i++) {
             info.input_generics[i].used =
                 info.input_generics[i].used || header.ps.IsGenericVectorActive(i);
         }
+        info.loads_position = info.loads_position || header.ps.imap_systemb.position != 0;
         return;
     }
+    if (info.loads_indexed_attributes) {
         for (size_t i = 0; i < info.input_generics.size(); i++) {
             info.input_generics[i].used =
                 info.input_generics[i].used || header.vtg.IsInputGenericVectorActive(i);
         }
+    }
+    if (info.stores_indexed_attributes) {
+        info.loads_position = info.loads_position || header.vtg.imap_systemb.position != 0;
         for (size_t i = 0; i < info.stores_generics.size(); i++) {
             info.stores_generics[i] =
                 info.stores_generics[i] || header.vtg.IsOutputGenericVectorActive(i);
         }
         info.stores_clip_distance =
             info.stores_clip_distance || header.vtg.omap_systemc.clip_distances != 0;
+        info.stores_position = info.stores_position || header.vtg.omap_systemb.position != 0;
+    }
 }
 
 } // Anonymous namespace

src/shader_recompiler/program_header.h

@@ -69,7 +69,20 @@ struct ProgramHeader {
     union {
         struct {
             INSERT_PADDING_BYTES_NOINIT(3); // ImapSystemValuesA
-            INSERT_PADDING_BYTES_NOINIT(1); // ImapSystemValuesB
+
+            union {
+                BitField<0, 1, u8> primitive_array_id;
+                BitField<1, 1, u8> rt_array_index;
+                BitField<2, 1, u8> viewport_index;
+                BitField<3, 1, u8> point_size;
+                BitField<4, 1, u8> position_x;
+                BitField<5, 1, u8> position_y;
+                BitField<6, 1, u8> position_z;
+                BitField<7, 1, u8> position_w;
+                BitField<0, 4, u8> first;
+                BitField<4, 4, u8> position;
+                u8 raw;
+            } imap_systemb;
 
             union {
                 BitField<0, 1, u8> x;
@@ -99,7 +112,20 @@ struct ProgramHeader {
             INSERT_PADDING_BYTES_NOINIT(5); // ImapFixedFncTexture[10]
             INSERT_PADDING_BYTES_NOINIT(1); // ImapReserved
             INSERT_PADDING_BYTES_NOINIT(3); // OmapSystemValuesA
-            INSERT_PADDING_BYTES_NOINIT(1); // OmapSystemValuesB
+
+            union {
+                BitField<0, 1, u8> primitive_array_id;
+                BitField<1, 1, u8> rt_array_index;
+                BitField<2, 1, u8> viewport_index;
+                BitField<3, 1, u8> point_size;
+                BitField<4, 1, u8> position_x;
+                BitField<5, 1, u8> position_y;
+                BitField<6, 1, u8> position_z;
+                BitField<7, 1, u8> position_w;
+                BitField<0, 4, u8> first;
+                BitField<4, 4, u8> position;
+                u8 raw;
+            } omap_systemb;
 
             union {
                 BitField<0, 1, u8> x;
@@ -148,7 +174,20 @@ struct ProgramHeader {
 
         struct {
             INSERT_PADDING_BYTES_NOINIT(3); // ImapSystemValuesA
-            INSERT_PADDING_BYTES_NOINIT(1); // ImapSystemValuesB
+
+            union {
+                BitField<0, 1, u8> primitive_array_id;
+                BitField<1, 1, u8> rt_array_index;
+                BitField<2, 1, u8> viewport_index;
+                BitField<3, 1, u8> point_size;
+                BitField<4, 1, u8> position_x;
+                BitField<5, 1, u8> position_y;
+                BitField<6, 1, u8> position_z;
+                BitField<7, 1, u8> position_w;
+                BitField<0, 4, u8> first;
+                BitField<4, 4, u8> position;
+                u8 raw;
+            } imap_systemb;
 
             union {
                 BitField<0, 2, PixelImap> x;