[SPIR-V] Some initial bits of the translator

src/xenia/gpu/spirv_shader_translator.cc

@@ -0,0 +1,151 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2020 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#include "xenia/gpu/spirv_shader_translator.h"
+
+#include <memory>
+#include <vector>
+
+#include "third_party/glslang/SPIRV/GLSL.std.450.h"
+
+namespace xe {
+namespace gpu {
+
+SpirvShaderTranslator::SpirvShaderTranslator(bool supports_clip_distance,
+                                             bool supports_cull_distance)
+    : supports_clip_distance_(supports_clip_distance),
+      supports_cull_distance_(supports_cull_distance) {}
+
+void SpirvShaderTranslator::Reset() {
+  ShaderTranslator::Reset();
+
+  builder_.reset();
+}
+
+void SpirvShaderTranslator::StartTranslation() {
+  // TODO(Triang3l): Once tool ID (likely 26) is registered in SPIRV-Headers,
+  // use it instead.
+  // TODO(Triang3l): Logger.
+  builder_ = std::make_unique<spv::Builder>(0x10000, 0xFFFF0001, nullptr);
+
+  builder_->addCapability(IsSpirvTessEvalShader() ? spv::CapabilityTessellation
+                                                  : spv::CapabilityShader);
+  ext_inst_glsl_std_450_ = builder_->import("GLSL.std.450");
+  builder_->setMemoryModel(spv::AddressingModelLogical,
+                           spv::MemoryModelGLSL450);
+  builder_->setSource(spv::SourceLanguageUnknown, 0);
+
+  type_void_ = builder_->makeVoidType();
+  type_float_ = builder_->makeFloatType(32);
+  type_float2_ = builder_->makeVectorType(type_float_, 2);
+  type_float3_ = builder_->makeVectorType(type_float_, 3);
+  type_float4_ = builder_->makeVectorType(type_float_, 4);
+  type_int_ = builder_->makeIntType(32);
+
+  if (IsSpirvVertexOrTessEvalShader()) {
+    StartVertexOrTessEvalShaderBeforeMain();
+  }
+
+  // Begin the main function.
+  std::vector<spv::Id> main_param_types;
+  std::vector<std::vector<spv::Decoration>> main_precisions;
+  spv::Block* main_entry;
+  builder_->makeFunctionEntry(spv::NoPrecision, type_void_, "main",
+                              main_param_types, main_precisions, &main_entry);
+
+  // Begin ucode translation.
+  if (register_count()) {
+    var_main_registers_ = builder_->createVariable(
+        spv::NoPrecision, spv::StorageClassFunction,
+        builder_->makeArrayType(
+            type_float4_, builder_->makeUintConstant(register_count()), 0),
+        "xe_r");
+  }
+}
+
+std::vector<uint8_t> SpirvShaderTranslator::CompleteTranslation() {
+  if (IsSpirvVertexOrTessEvalShader()) {
+    CompleteVertexOrTessEvalShaderInMain();
+  }
+
+  // End the main function..
+  builder_->leaveFunction();
+
+  // TODO(Triang3l): Avoid copy?
+  std::vector<unsigned int> module_uints;
+  builder_->dump(module_uints);
+  std::vector<uint8_t> module_bytes;
+  module_bytes.reserve(sizeof(unsigned int) * module_uints.size());
+  module_bytes.insert(module_bytes.cend(),
+                      reinterpret_cast<const uint8_t*>(module_uints.data()),
+                      reinterpret_cast<const uint8_t*>(module_uints.data()) +
+                          sizeof(unsigned int) * module_uints.size());
+  return module_bytes;
+}
+
+void SpirvShaderTranslator::StartVertexOrTessEvalShaderBeforeMain() {
+  // Create the inputs.
+  if (IsSpirvTessEvalShader()) {
+    input_vertex_index_ = builder_->createVariable(
+        spv::NoPrecision, spv::StorageClassInput, type_int_, "gl_PrimitiveID");
+    builder_->addDecoration(input_vertex_index_, spv::DecorationBuiltIn,
+                            spv::BuiltInPrimitiveId);
+  } else {
+    input_primitive_id_ = builder_->createVariable(
+        spv::NoPrecision, spv::StorageClassInput, type_int_, "gl_VertexIndex");
+    builder_->addDecoration(input_primitive_id_, spv::DecorationBuiltIn,
+                            spv::BuiltInVertexIndex);
+  }
+
+  // Create the entire GLSL 4.50 gl_PerVertex output similar to what glslang
+  // does. Members (like gl_PointSize) don't need to be used, and also
+  // ClipDistance and CullDistance may exist even if the device doesn't support
+  // them, as long as the capabilities aren't enabled, and nothing is stored to
+  // them.
+  if (supports_clip_distance_) {
+    builder_->addCapability(spv::CapabilityClipDistance);
+  }
+  if (supports_cull_distance_) {
+    builder_->addCapability(spv::CapabilityCullDistance);
+  }
+  std::vector<spv::Id> struct_per_vertex_members;
+  struct_per_vertex_members.reserve(kOutputPerVertexMemberCount);
+  struct_per_vertex_members.push_back(type_float4_);
+  struct_per_vertex_members.push_back(type_float_);
+  // TODO(Triang3l): Specialization constant for ucp_cull_only_ena, for 6 + 1
+  // or 1 + 7 array sizes.
+  struct_per_vertex_members.push_back(builder_->makeArrayType(
+      type_float_, builder_->makeUintConstant(supports_clip_distance_ ? 6 : 1),
+      0));
+  struct_per_vertex_members.push_back(
+      builder_->makeArrayType(type_float_, builder_->makeUintConstant(1), 0));
+  spv::Id type_struct_per_vertex =
+      builder_->makeStructType(struct_per_vertex_members, "gl_PerVertex");
+  builder_->addMemberDecoration(type_struct_per_vertex,
+                                kOutputPerVertexMemberPosition,
+                                spv::DecorationBuiltIn, spv::BuiltInPosition);
+  builder_->addMemberDecoration(type_struct_per_vertex,
+                                kOutputPerVertexMemberPointSize,
+                                spv::DecorationBuiltIn, spv::BuiltInPointSize);
+  builder_->addMemberDecoration(
+      type_struct_per_vertex, kOutputPerVertexMemberClipDistance,
+      spv::DecorationBuiltIn, spv::BuiltInClipDistance);
+  builder_->addMemberDecoration(
+      type_struct_per_vertex, kOutputPerVertexMemberCullDistance,
+      spv::DecorationBuiltIn, spv::BuiltInCullDistance);
+  builder_->addDecoration(type_struct_per_vertex, spv::DecorationBlock);
+  output_per_vertex_ =
+      builder_->createVariable(spv::NoPrecision, spv::StorageClassOutput,
+                               type_struct_per_vertex, "xe_out_gl_PerVertex");
+}
+
+void SpirvShaderTranslator::CompleteVertexOrTessEvalShaderInMain() {}
+
+}  // namespace gpu
+}  // namespace xe