3 files changed, 134 insertions, 4 deletions

diff --git a/src/shader_recompiler/CMakeLists.txt b/src/shader_recompiler/CMakeLists.txt
index 1f286484c..5f3868bfe 100644
--- a/src/shader_recompiler/CMakeLists.txt
+++ b/src/shader_recompiler/CMakeLists.txt
@@ -124,6 +124,7 @@ add_library(shader_recompiler STATIC
     frontend/maxwell/translate/impl/select_source_with_predicate.cpp
     frontend/maxwell/translate/impl/texture_fetch.cpp
     frontend/maxwell/translate/impl/texture_fetch_swizzled.cpp
+    frontend/maxwell/translate/impl/texture_gather_swizzled.cpp
     frontend/maxwell/translate/impl/texture_gather.cpp
     frontend/maxwell/translate/impl/vote.cpp
     frontend/maxwell/translate/impl/warp_shuffle.cpp
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp b/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
index e59c3326e..788765c21 100644
--- a/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
@@ -349,10 +349,6 @@ void TranslatorVisitor::TLD_b(u64) {
     ThrowNotImplemented(Opcode::TLD_b);
 }
 
-void TranslatorVisitor::TLD4S(u64) {
-    ThrowNotImplemented(Opcode::TLD4S);
-}
-
 void TranslatorVisitor::TLDS(u64) {
     ThrowNotImplemented(Opcode::TLDS);
 }
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/texture_gather_swizzled.cpp b/src/shader_recompiler/frontend/maxwell/translate/impl/texture_gather_swizzled.cpp
new file mode 100644
index 000000000..beab515ad
--- /dev/null
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/texture_gather_swizzled.cpp
@@ -0,0 +1,133 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <utility>
+
+#include "common/bit_field.h"
+#include "common/common_types.h"
+#include "shader_recompiler/frontend/ir/modifiers.h"
+#include "shader_recompiler/frontend/maxwell/translate/impl/impl.h"
+
+namespace Shader::Maxwell {
+namespace {
+enum class Precision : u64 {
+    F32,
+    F16,
+};
+
+enum class ComponentType : u64 {
+    R = 0,
+    G = 1,
+    B = 2,
+    A = 3,
+};
+
+union Encoding {
+    u64 raw;
+    BitField<55, 1, Precision> precision;
+    BitField<52, 2, ComponentType> component_type;
+    BitField<51, 1, u64> aoffi;
+    BitField<50, 1, u64> dc;
+    BitField<49, 1, u64> nodep;
+    BitField<28, 8, IR::Reg> dest_reg_b;
+    BitField<0, 8, IR::Reg> dest_reg_a;
+    BitField<8, 8, IR::Reg> src_reg_a;
+    BitField<20, 8, IR::Reg> src_reg_b;
+    BitField<36, 13, u64> cbuf_offset;
+};
+
+void CheckAlignment(IR::Reg reg, int alignment) {
+    if (!IR::IsAligned(reg, alignment)) {
+        throw NotImplementedException("Unaligned source register {}", reg);
+    }
+}
+
+IR::Value MakeOffset(TranslatorVisitor& v, IR::Reg reg) {
+    const IR::U32 value{v.X(reg)};
+    return v.ir.CompositeConstruct(v.ir.BitFieldExtract(value, v.ir.Imm32(0), v.ir.Imm32(6), true),
+                                   v.ir.BitFieldExtract(value, v.ir.Imm32(8), v.ir.Imm32(6), true));
+}
+
+IR::Value Sample(TranslatorVisitor& v, u64 insn) {
+    const Encoding tld4s{insn};
+    const IR::U32 handle{v.ir.Imm32(static_cast<u32>(tld4s.cbuf_offset * 4))};
+    const IR::Reg reg_a{tld4s.src_reg_a};
+    const IR::Reg reg_b{tld4s.src_reg_b};
+    IR::TextureInstInfo info{};
+    if (tld4s.precision == Precision::F16) {
+        info.relaxed_precision.Assign(1);
+    }
+    info.gather_component.Assign(static_cast<u32>(tld4s.component_type.Value()));
+    info.type.Assign(tld4s.dc != 0 ? Shader::TextureType::Shadow2D : Shader::TextureType::Color2D);
+    IR::Value coords;
+    if (tld4s.aoffi != 0) {
+        CheckAlignment(reg_a, 2);
+        coords = v.ir.CompositeConstruct(v.F(reg_a), v.F(reg_a + 1));
+        IR::Value offset = MakeOffset(v, reg_b);
+        if (tld4s.dc != 0) {
+            CheckAlignment(reg_b, 2);
+            IR::F32 dref = v.F(reg_b + 1);
+            return v.ir.ImageGatherDref(handle, coords, offset, {}, dref, info);
+        }
+        return v.ir.ImageGather(handle, coords, offset, {}, info);
+    }
+    if (tld4s.dc != 0) {
+        CheckAlignment(reg_a, 2);
+        coords = v.ir.CompositeConstruct(v.F(reg_a), v.F(reg_a + 1));
+        IR::F32 dref = v.F(reg_b);
+        return v.ir.ImageGatherDref(handle, coords, {}, {}, dref, info);
+    }
+    coords = v.ir.CompositeConstruct(v.F(reg_a), v.F(reg_b));
+    return v.ir.ImageGather(handle, coords, {}, {}, info);
+}
+
+IR::Reg RegStoreComponent32(u64 insn, size_t index) {
+    const Encoding tlds4{insn};
+    switch (index) {
+    case 0:
+        return tlds4.dest_reg_a;
+    case 1:
+        CheckAlignment(tlds4.dest_reg_a, 2);
+        return tlds4.dest_reg_a + 1;
+    case 2:
+        return tlds4.dest_reg_b;
+    case 3:
+        CheckAlignment(tlds4.dest_reg_b, 2);
+        return tlds4.dest_reg_b + 1;
+    }
+    throw LogicError("Invalid store index {}", index);
+}
+
+void Store32(TranslatorVisitor& v, u64 insn, const IR::Value& sample) {
+    for (size_t component = 0; component < 4; ++component) {
+        const IR::Reg dest{RegStoreComponent32(insn, component)};
+        v.F(dest, IR::F32{v.ir.CompositeExtract(sample, component)});
+    }
+}
+
+IR::U32 Pack(TranslatorVisitor& v, const IR::F32& lhs, const IR::F32& rhs) {
+    return v.ir.PackHalf2x16(v.ir.CompositeConstruct(lhs, rhs));
+}
+
+void Store16(TranslatorVisitor& v, u64 insn, const IR::Value& sample) {
+    std::array<IR::F32, 4> swizzled;
+    for (size_t component = 0; component < 4; ++component) {
+        swizzled[component] = IR::F32{v.ir.CompositeExtract(sample, component)};
+    }
+    const Encoding tld4s{insn};
+    v.X(tld4s.dest_reg_a, Pack(v, swizzled[0], swizzled[1]));
+    v.X(tld4s.dest_reg_b, Pack(v, swizzled[2], swizzled[3]));
+}
+} // Anonymous namespace
+
+void TranslatorVisitor::TLD4S(u64 insn) {
+    const IR::Value sample{Sample(*this, insn)};
+    if (Encoding{insn}.precision == Precision::F32) {
+        Store32(*this, insn, sample);
+    } else {
+        Store16(*this, insn, sample);
+    }
+}
+
+} // namespace Shader::Maxwell