From 9097301d924ac9d873f04acdc247e8023edf1811 Mon Sep 17 00:00:00 2001
From: ReinUsesLisp <reinuseslisp@airmail.cc>
Date: Sat, 27 Apr 2019 03:04:13 -0300
Subject: [PATCH] shader: Implement bindless images

---
 src/video_core/shader/decode/image.cpp | 30 ++++++++++++++++++++++++--
 src/video_core/shader/node.h           |  9 ++++++++
 src/video_core/shader/shader_ir.h      |  3 +++
 3 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/src/video_core/shader/decode/image.cpp b/src/video_core/shader/decode/image.cpp
index 66fdf57140..199b6b7937 100644
--- a/src/video_core/shader/decode/image.cpp
+++ b/src/video_core/shader/decode/image.cpp
@@ -55,8 +55,9 @@ u32 ShaderIR::DecodeImage(NodeBlock& bb, u32 pc) {
             coords.push_back(GetRegister(instr.gpr8.Value() + i));
         }
 
-        ASSERT(instr.sust.is_immediate);
-        const auto& image{GetImage(instr.image, instr.sust.image_type)};
+        const auto type{instr.sust.image_type};
+        const auto& image{instr.sust.is_immediate ? GetImage(instr.image, type)
+                                                  : GetBindlessImage(instr.gpr39, type)};
         MetaImage meta{image, values};
         const Node store{Operation(OperationCode::ImageStore, meta, std::move(coords))};
         bb.push_back(store);
@@ -86,4 +87,29 @@ const Image& ShaderIR::GetImage(Tegra::Shader::Image image, Tegra::Shader::Image
     return *used_images.emplace(entry).first;
 }
 
+const Image& ShaderIR::GetBindlessImage(Tegra::Shader::Register reg,
+                                        Tegra::Shader::ImageType type) {
+    const Node image_register{GetRegister(reg)};
+    const Node base_image{
+        TrackCbuf(image_register, global_code, static_cast<s64>(global_code.size()))};
+    const auto cbuf{std::get_if<CbufNode>(base_image)};
+    const auto cbuf_offset_imm{std::get_if<ImmediateNode>(cbuf->GetOffset())};
+    const auto cbuf_offset{cbuf_offset_imm->GetValue()};
+    const auto cbuf_index{cbuf->GetIndex()};
+    const auto cbuf_key{(static_cast<u64>(cbuf_index) << 32) | static_cast<u64>(cbuf_offset)};
+
+    // If this image has already been used, return the existing mapping.
+    const auto itr{std::find_if(used_images.begin(), used_images.end(),
+                                [=](const Image& entry) { return entry.GetOffset() == cbuf_key; })};
+    if (itr != used_images.end()) {
+        ASSERT(itr->GetType() == type);
+        return *itr;
+    }
+
+    // Otherwise create a new mapping for this image.
+    const std::size_t next_index{used_images.size()};
+    const Image entry{cbuf_index, cbuf_offset, next_index, type};
+    return *used_images.emplace(entry).first;
+}
+
 } // namespace VideoCommon::Shader
diff --git a/src/video_core/shader/node.h b/src/video_core/shader/node.h
index 8b8d83ae7f..2bf535928b 100644
--- a/src/video_core/shader/node.h
+++ b/src/video_core/shader/node.h
@@ -270,6 +270,15 @@ public:
     explicit Image(std::size_t offset, std::size_t index, Tegra::Shader::ImageType type)
         : offset{offset}, index{index}, type{type}, is_bindless{false} {}
 
+    explicit Image(u32 cbuf_index, u32 cbuf_offset, std::size_t index,
+                   Tegra::Shader::ImageType type)
+        : offset{(static_cast<u64>(cbuf_index) << 32) | cbuf_offset}, index{index}, type{type},
+          is_bindless{true} {}
+
+    explicit Image(std::size_t offset, std::size_t index, Tegra::Shader::ImageType type,
+                   bool is_bindless)
+        : offset{offset}, index{index}, type{type}, is_bindless{is_bindless} {}
+
     std::size_t GetOffset() const {
         return offset;
     }
diff --git a/src/video_core/shader/shader_ir.h b/src/video_core/shader/shader_ir.h
index c7f264371e..e225482081 100644
--- a/src/video_core/shader/shader_ir.h
+++ b/src/video_core/shader/shader_ir.h
@@ -262,6 +262,9 @@ private:
     /// Accesses an image.
     const Image& GetImage(Tegra::Shader::Image image, Tegra::Shader::ImageType type);
 
+    /// Access a bindless image sampler.
+    const Image& GetBindlessImage(Tegra::Shader::Register reg, Tegra::Shader::ImageType type);
+
     /// Extracts a sequence of bits from a node
     Node BitfieldExtract(Node value, u32 offset, u32 bits);