shader_recompiler: Fix incorrect bary coord loads when unsupported (#3303)

* shader_recompiler: Fix incorrect bary coord loads when unsupported

Also properly set sample rate shading

* emit_spirv: Implement BaryCoordSmoothCentroid

src/shader_recompiler/backend/spirv/emit_spirv.cpp

@@ -241,7 +241,8 @@ spv::ExecutionMode ExecutionMode(AmdGpu::TessellationPartitioning spacing) {
     UNREACHABLE_MSG("Tessellation spacing {}", spacing);
 }
 
-void SetupCapabilities(const Info& info, const Profile& profile, EmitContext& ctx) {
+void SetupCapabilities(const Info& info, const Profile& profile, const RuntimeInfo& runtime_info,
+                       EmitContext& ctx) {
     ctx.AddCapability(spv::Capability::Image1D);
     ctx.AddCapability(spv::Capability::Sampled1D);
     ctx.AddCapability(spv::Capability::ImageQuery);
@@ -300,8 +301,8 @@ void SetupCapabilities(const Info& info, const Profile& profile, EmitContext& ct
             ctx.AddExtension("SPV_KHR_fragment_shader_barycentric");
             ctx.AddCapability(spv::Capability::FragmentBarycentricKHR);
         }
-        if (info.loads.GetAny(IR::Attribute::BaryCoordSmoothSample) ||
+        if (runtime_info.fs_info.addr_flags.linear_sample_ena ||
-            info.loads.GetAny(IR::Attribute::BaryCoordNoPerspSample)) {
+            runtime_info.fs_info.addr_flags.persp_sample_ena) {
             ctx.AddCapability(spv::Capability::SampleRateShading);
         }
     }
@@ -443,7 +444,7 @@ std::vector<u32> EmitSPIRV(const Profile& profile, const RuntimeInfo& runtime_in
     EmitContext ctx{profile, runtime_info, program.info, binding};
     const Id main{DefineMain(ctx, program)};
     DefineEntryPoint(program.info, ctx, main);
-    SetupCapabilities(program.info, profile, ctx);
+    SetupCapabilities(program.info, profile, runtime_info, ctx);
     SetupFloatMode(ctx, profile, runtime_info, main);
     PatchPhiNodes(program, ctx);
     binding.user_data += program.info.ud_mask.NumRegs();

src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp

@@ -208,6 +208,10 @@ Id EmitGetAttribute(EmitContext& ctx, IR::Attribute attr, u32 comp, u32 index) {
     case IR::Attribute::BaryCoordSmooth:
         return ctx.OpLoad(ctx.F32[1], ctx.OpAccessChain(ctx.input_f32, ctx.bary_coord_smooth,
                                                         ctx.ConstU32(comp)));
+    case IR::Attribute::BaryCoordSmoothCentroid:
+        return ctx.OpLoad(
+            ctx.F32[1],
+            ctx.OpAccessChain(ctx.input_f32, ctx.bary_coord_smooth_centroid, ctx.ConstU32(comp)));
     case IR::Attribute::BaryCoordSmoothSample:
         return ctx.OpLoad(ctx.F32[1], ctx.OpAccessChain(ctx.input_f32, ctx.bary_coord_smooth_sample,
                                                         ctx.ConstU32(comp)));

src/shader_recompiler/backend/spirv/spirv_emit_context.cpp

@@ -384,8 +384,16 @@ void EmitContext::DefineInputs() {
             } else if (profile.supports_fragment_shader_barycentric) {
                 bary_coord_smooth =
                     DefineVariable(F32[3], spv::BuiltIn::BaryCoordKHR, spv::StorageClass::Input);
-            } else {
+            }
-                bary_coord_smooth = ConstF32(0.f, 0.f);
+        }
+        if (info.loads.GetAny(IR::Attribute::BaryCoordSmoothCentroid)) {
+            if (profile.supports_amd_shader_explicit_vertex_parameter) {
+                bary_coord_smooth_centroid = DefineVariable(
+                    F32[2], spv::BuiltIn::BaryCoordSmoothCentroidAMD, spv::StorageClass::Input);
+            } else if (profile.supports_fragment_shader_barycentric) {
+                bary_coord_smooth_centroid =
+                    DefineVariable(F32[3], spv::BuiltIn::BaryCoordKHR, spv::StorageClass::Input);
+                // Decorate(bary_coord_smooth_centroid, spv::Decoration::Centroid);
             }
         }
         if (info.loads.GetAny(IR::Attribute::BaryCoordSmoothSample)) {
@@ -396,8 +404,6 @@ void EmitContext::DefineInputs() {
                 bary_coord_smooth_sample =
                     DefineVariable(F32[3], spv::BuiltIn::BaryCoordKHR, spv::StorageClass::Input);
                 // Decorate(bary_coord_smooth_sample, spv::Decoration::Sample);
-            } else {
-                bary_coord_smooth_sample = ConstF32(0.f, 0.f);
             }
         }
         if (info.loads.GetAny(IR::Attribute::BaryCoordNoPersp)) {
@@ -407,8 +413,6 @@ void EmitContext::DefineInputs() {
             } else if (profile.supports_fragment_shader_barycentric) {
                 bary_coord_nopersp = DefineVariable(F32[3], spv::BuiltIn::BaryCoordNoPerspKHR,
                                                     spv::StorageClass::Input);
-            } else {
-                bary_coord_nopersp = ConstF32(0.f, 0.f);
             }
         }
         for (s32 i = 0; i < runtime_info.fs_info.num_inputs; i++) {

src/shader_recompiler/backend/spirv/spirv_emit_context.h

@@ -280,6 +280,7 @@ public:
     Id shared_memory_u64_type{};
 
     Id bary_coord_smooth{};
+    Id bary_coord_smooth_centroid{};
     Id bary_coord_smooth_sample{};
     Id bary_coord_nopersp{};
 

src/shader_recompiler/frontend/translate/translate.cpp

@@ -126,7 +126,10 @@ void Translator::EmitPrologue(IR::Block* first_block) {
     case LogicalStage::Fragment:
         dst_vreg =
             IterateBarycentrics(runtime_info, [this](u32 vreg, IR::Attribute attrib, u32 comp) {
-                ir.SetVectorReg(IR::VectorReg(vreg), ir.GetAttribute(attrib, comp));
+                if (profile.supports_amd_shader_explicit_vertex_parameter ||
+                    profile.supports_fragment_shader_barycentric) {
+                    ir.SetVectorReg(IR::VectorReg(vreg), ir.GetAttribute(attrib, comp));
+                }
             });
         if (runtime_info.fs_info.addr_flags.pos_x_float_ena) {
             if (runtime_info.fs_info.en_flags.pos_x_float_ena) {