From 3764750339fa60f2d79cf3abe1b91ca42ba61401 Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Sat, 15 May 2021 18:14:29 -0300
Subject: [PATCH] glasm: Add graphics specific shader declarations to GLASM

---
 .../backend/glasm/emit_context.cpp            | 37 +++++++++++++++++++
 .../backend/glasm/emit_glasm.cpp              | 32 +++++++++++++---
 2 files changed, 63 insertions(+), 6 deletions(-)

diff --git a/src/shader_recompiler/backend/glasm/emit_context.cpp b/src/shader_recompiler/backend/glasm/emit_context.cpp
index f9d83dd91..66c954ff6 100644
--- a/src/shader_recompiler/backend/glasm/emit_context.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_context.cpp
@@ -2,10 +2,25 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <string_view>
+
 #include "shader_recompiler/backend/glasm/emit_context.h"
 #include "shader_recompiler/frontend/ir/program.h"
 
 namespace Shader::Backend::GLASM {
+namespace {
+std::string_view InterpDecorator(Interpolation interp) {
+    switch (interp) {
+    case Interpolation::Smooth:
+        return "";
+    case Interpolation::Flat:
+        return "FLAT ";
+    case Interpolation::NoPerspective:
+        return "NOPERSPECTIVE ";
+    }
+    throw InvalidArgument("Invalid interpolation {}", interp);
+}
+} // Anonymous namespace
 
 EmitContext::EmitContext(IR::Program& program) {
     // FIXME: Temporary partial implementation
@@ -42,6 +57,28 @@ EmitContext::EmitContext(IR::Program& program) {
         stage_name = "compute";
         break;
     }
+    for (size_t index = 0; index < program.info.input_generics.size(); ++index) {
+        const auto& generic{program.info.input_generics[index]};
+        if (generic.used) {
+            Add("{}ATTRIB in_attr{}[]={{{}.attrib[{}..{}]}};",
+                InterpDecorator(generic.interpolation), index, stage_name, index, index);
+        }
+    }
+    for (size_t index = 0; index < program.info.stores_frag_color.size(); ++index) {
+        if (!program.info.stores_frag_color[index]) {
+            continue;
+        }
+        if (index == 0) {
+            Add("OUTPUT frag_color0=result.color;");
+        } else {
+            Add("OUTPUT frag_color{}[]=result.color[{}];", index, index);
+        }
+    }
+    for (size_t index = 0; index < program.info.stores_generics.size(); ++index) {
+        if (program.info.stores_generics[index]) {
+            Add("OUTPUT out_attr{}[]={{result.attrib[{}..{}]}};", index, index, index);
+        }
+    }
 }
 
 } // namespace Shader::Backend::GLASM
diff --git a/src/shader_recompiler/backend/glasm/emit_glasm.cpp b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
index 0b70bf3f6..ab6790ce8 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
@@ -261,6 +261,12 @@ void EmitCode(EmitContext& ctx, const IR::Program& program) {
 }
 
 void SetupOptions(std::string& header, Info info) {
+    // TODO: Track the shared atomic ops
+    header += "OPTION NV_internal;"
+              "OPTION NV_shader_storage_buffer;"
+              "OPTION NV_gpu_program_fp64;"
+              "OPTION NV_bindless_texture;"
+              "OPTION ARB_derivative_control;";
     if (info.uses_int64_bit_atomics) {
         header += "OPTION NV_shader_atomic_int64;";
     }
@@ -276,10 +282,25 @@ void SetupOptions(std::string& header, Info info) {
     if (info.uses_subgroup_shuffles) {
         header += "OPTION NV_shader_thread_shuffle;";
     }
-    // TODO: Track the shared atomic ops
-    header += "OPTION NV_shader_storage_buffer;"
-              "OPTION NV_gpu_program_fp64;"
-              "OPTION NV_bindless_texture;";
+}
+
+std::string_view StageHeader(Stage stage) {
+    switch (stage) {
+    case Stage::VertexA:
+    case Stage::VertexB:
+        return "!!NVvp5.0\n";
+    case Stage::TessellationControl:
+        return "!!NVtcs5.0\n";
+    case Stage::TessellationEval:
+        return "!!NVtes5.0\n";
+    case Stage::Geometry:
+        return "!!NVgp5.0\n";
+    case Stage::Fragment:
+        return "!!NVfp5.0\n";
+    case Stage::Compute:
+        return "!!NVcp5.0\n";
+    }
+    throw InvalidArgument("Invalid stage {}", stage);
 }
 } // Anonymous namespace
 
@@ -287,8 +308,7 @@ std::string EmitGLASM(const Profile&, IR::Program& program, Bindings&) {
     EmitContext ctx{program};
     Precolor(ctx, program);
     EmitCode(ctx, program);
-    std::string header = "!!NVcp5.0\n"
-                         "OPTION NV_internal;";
+    std::string header{StageHeader(program.stage)};
     SetupOptions(header, program.info);
     switch (program.stage) {
     case Stage::Compute: