14 files changed, 87 insertions, 4 deletions

diff --git a/src/shader_recompiler/CMakeLists.txt b/src/shader_recompiler/CMakeLists.txt
index 44ab929b7..5ce420cbf 100644
--- a/src/shader_recompiler/CMakeLists.txt
+++ b/src/shader_recompiler/CMakeLists.txt
@@ -89,6 +89,7 @@ add_library(shader_recompiler STATIC
     frontend/maxwell/translate/impl/floating_point_multiply.cpp
     frontend/maxwell/translate/impl/floating_point_range_reduction.cpp
     frontend/maxwell/translate/impl/floating_point_set_predicate.cpp
+    frontend/maxwell/translate/impl/floating_point_swizzled_add.cpp
     frontend/maxwell/translate/impl/half_floating_point_add.cpp
     frontend/maxwell/translate/impl/half_floating_point_fused_multiply_add.cpp
     frontend/maxwell/translate/impl/half_floating_point_helper.cpp
diff --git a/src/shader_recompiler/backend/spirv/emit_context.cpp b/src/shader_recompiler/backend/spirv/emit_context.cpp
index 96d0e9b4d..7531f8b21 100644
--- a/src/shader_recompiler/backend/spirv/emit_context.cpp
+++ b/src/shader_recompiler/backend/spirv/emit_context.cpp
@@ -393,6 +393,14 @@ void EmitContext::DefineInputs(const Info& info) {
         subgroup_local_invocation_id =
             DefineInput(*this, U32[1], spv::BuiltIn::SubgroupLocalInvocationId);
     }
+    if (info.uses_fswzadd) {
+        const Id f32_one{Constant(F32[1], 1.0f)};
+        const Id f32_minus_one{Constant(F32[1], -1.0f)};
+        const Id f32_zero{Constant(F32[1], 0.0f)};
+        fswzadd_lut_a = ConstantComposite(F32[4], f32_minus_one, f32_one, f32_minus_one, f32_zero);
+        fswzadd_lut_b =
+            ConstantComposite(F32[4], f32_minus_one, f32_minus_one, f32_one, f32_minus_one);
+    }
     if (info.loads_position) {
         const bool is_fragment{stage != Stage::Fragment};
         const spv::BuiltIn built_in{is_fragment ? spv::BuiltIn::Position : spv::BuiltIn::FragCoord};
diff --git a/src/shader_recompiler/backend/spirv/emit_context.h b/src/shader_recompiler/backend/spirv/emit_context.h
index 1a4e8221a..ffac39c4f 100644
--- a/src/shader_recompiler/backend/spirv/emit_context.h
+++ b/src/shader_recompiler/backend/spirv/emit_context.h
@@ -103,6 +103,8 @@ public:
     Id vertex_index{};
     Id base_vertex{};
     Id front_face{};
+    Id fswzadd_lut_a{};
+    Id fswzadd_lut_b{};
 
     Id local_memory{};
 
diff --git a/src/shader_recompiler/backend/spirv/emit_spirv.h b/src/shader_recompiler/backend/spirv/emit_spirv.h
index 02648d769..3d0c6f7ba 100644
--- a/src/shader_recompiler/backend/spirv/emit_spirv.h
+++ b/src/shader_recompiler/backend/spirv/emit_spirv.h
@@ -397,5 +397,6 @@ Id EmitShuffleDown(EmitContext& ctx, IR::Inst* inst, Id value, Id index, Id clam
                    Id segmentation_mask);
 Id EmitShuffleButterfly(EmitContext& ctx, IR::Inst* inst, Id value, Id index, Id clamp,
                         Id segmentation_mask);
+Id EmitFSwizzleAdd(EmitContext& ctx, Id op_a, Id op_b, Id swizzle);
 
 } // namespace Shader::Backend::SPIRV
diff --git a/src/shader_recompiler/backend/spirv/emit_spirv_warp.cpp b/src/shader_recompiler/backend/spirv/emit_spirv_warp.cpp
index 44d8a347f..cbc5b1c96 100644
--- a/src/shader_recompiler/backend/spirv/emit_spirv_warp.cpp
+++ b/src/shader_recompiler/backend/spirv/emit_spirv_warp.cpp
@@ -132,4 +132,20 @@ Id EmitShuffleButterfly(EmitContext& ctx, IR::Inst* inst, Id value, Id index, Id
     return SelectValue(ctx, in_range, value, src_thread_id);
 }
 
+Id EmitFSwizzleAdd(EmitContext& ctx, Id op_a, Id op_b, Id swizzle) {
+    const Id three{ctx.Constant(ctx.U32[1], 3)};
+    Id mask{ctx.OpLoad(ctx.U32[1], ctx.subgroup_local_invocation_id)};
+    mask = ctx.OpBitwiseAnd(ctx.U32[1], mask, three);
+    mask = ctx.OpShiftLeftLogical(ctx.U32[1], mask, ctx.Constant(ctx.U32[1], 1));
+    mask = ctx.OpShiftRightLogical(ctx.U32[1], swizzle, mask);
+    mask = ctx.OpBitwiseAnd(ctx.U32[1], mask, three);
+
+    const Id modifier_a{ctx.OpVectorExtractDynamic(ctx.F32[1], ctx.fswzadd_lut_a, mask)};
+    const Id modifier_b{ctx.OpVectorExtractDynamic(ctx.F32[1], ctx.fswzadd_lut_b, mask)};
+
+    const Id result_a{ctx.OpFMul(ctx.F32[1], op_a, modifier_a)};
+    const Id result_b{ctx.OpFMul(ctx.F32[1], op_b, modifier_b)};
+    return ctx.OpFAdd(ctx.F32[1], result_a, result_b);
+}
+
 } // namespace Shader::Backend::SPIRV
diff --git a/src/shader_recompiler/frontend/ir/ir_emitter.cpp b/src/shader_recompiler/frontend/ir/ir_emitter.cpp
index 552472487..505fba46a 100644
--- a/src/shader_recompiler/frontend/ir/ir_emitter.cpp
+++ b/src/shader_recompiler/frontend/ir/ir_emitter.cpp
@@ -1602,4 +1602,7 @@ U32 IREmitter::ShuffleButterfly(const IR::U32& value, const IR::U32& index, cons
                                 const IR::U32& seg_mask) {
     return Inst<U32>(Opcode::ShuffleButterfly, value, index, clamp, seg_mask);
 }
+F32 IREmitter::FSwizzleAdd(const F32& a, const F32& b, const U32& swizzle, FpControl control) {
+    return Inst<F32>(Opcode::FSwizzleAdd, Flags{control}, a, b, swizzle);
+}
 } // namespace Shader::IR
diff --git a/src/shader_recompiler/frontend/ir/ir_emitter.h b/src/shader_recompiler/frontend/ir/ir_emitter.h
index 17bc32fc8..8f3325738 100644
--- a/src/shader_recompiler/frontend/ir/ir_emitter.h
+++ b/src/shader_recompiler/frontend/ir/ir_emitter.h
@@ -277,6 +277,8 @@ public:
                                   const IR::U32& seg_mask);
     [[nodiscard]] U32 ShuffleButterfly(const IR::U32& value, const IR::U32& index,
                                        const IR::U32& clamp, const IR::U32& seg_mask);
+    [[nodiscard]] F32 FSwizzleAdd(const F32& a, const F32& b, const U32& swizzle,
+                                  FpControl control = {});
 
 private:
     IR::Block::iterator insertion_point;
diff --git a/src/shader_recompiler/frontend/ir/opcodes.inc b/src/shader_recompiler/frontend/ir/opcodes.inc
index fb79e3d8d..717aa71ca 100644
--- a/src/shader_recompiler/frontend/ir/opcodes.inc
+++ b/src/shader_recompiler/frontend/ir/opcodes.inc
@@ -408,3 +408,4 @@ OPCODE(ShuffleIndex,                                        U32,            U32,
 OPCODE(ShuffleUp,                                           U32,            U32,            U32,            U32,            U32,                            )
 OPCODE(ShuffleDown,                                         U32,            U32,            U32,            U32,            U32,                            )
 OPCODE(ShuffleButterfly,                                    U32,            U32,            U32,            U32,            U32,                            )
+OPCODE(FSwizzleAdd,                                         F32,            F32,            F32,            U32,                                            )
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/floating_point_swizzled_add.cpp b/src/shader_recompiler/frontend/maxwell/translate/impl/floating_point_swizzled_add.cpp
new file mode 100644
index 000000000..e42921a21
--- /dev/null
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/floating_point_swizzled_add.cpp
@@ -0,0 +1,44 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/common_types.h"
+#include "shader_recompiler/exception.h"
+#include "shader_recompiler/frontend/maxwell/translate/impl/common_encoding.h"
+#include "shader_recompiler/frontend/maxwell/translate/impl/impl.h"
+
+namespace Shader::Maxwell {
+void TranslatorVisitor::FSWZADD(u64 insn) {
+    union {
+        u64 raw;
+        BitField<0, 8, IR::Reg> dest_reg;
+        BitField<28, 8, u64> swizzle;
+        BitField<38, 1, u64> ndv;
+        BitField<39, 2, FpRounding> round;
+        BitField<44, 1, u64> ftz;
+        BitField<47, 1, u64> cc;
+    } const fswzadd{insn};
+
+    if (fswzadd.ndv != 0) {
+        throw NotImplementedException("FSWZADD NDV");
+    }
+
+    const IR::F32 src_a{GetFloatReg8(insn)};
+    const IR::F32 src_b{GetFloatReg20(insn)};
+    const IR::U32 swizzle{ir.Imm32(static_cast<u32>(fswzadd.swizzle))};
+
+    const IR::FpControl fp_control{
+        .no_contraction{false},
+        .rounding{CastFpRounding(fswzadd.round)},
+        .fmz_mode{fswzadd.ftz != 0 ? IR::FmzMode::FTZ : IR::FmzMode::None},
+    };
+
+    const IR::F32 result{ir.FSwizzleAdd(src_a, src_b, swizzle, fp_control)};
+    F(fswzadd.dest_reg, result);
+
+    if (fswzadd.cc != 0) {
+        throw NotImplementedException("FSWZADD CC");
+    }
+}
+
+} // namespace Shader::Maxwell
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/impl.cpp b/src/shader_recompiler/frontend/maxwell/translate/impl/impl.cpp
index 9bae89c10..30b570ce4 100644
--- a/src/shader_recompiler/frontend/maxwell/translate/impl/impl.cpp
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/impl.cpp
@@ -91,6 +91,10 @@ IR::U32 TranslatorVisitor::GetReg39(u64 insn) {
     return X(reg.index);
 }
 
+IR::F32 TranslatorVisitor::GetFloatReg8(u64 insn) {
+    return ir.BitCast<IR::F32>(GetReg8(insn));
+}
+
 IR::F32 TranslatorVisitor::GetFloatReg20(u64 insn) {
     return ir.BitCast<IR::F32>(GetReg20(insn));
 }
diff --git a/src/shader_recompiler/frontend/maxwell/translate/impl/impl.h b/src/shader_recompiler/frontend/maxwell/translate/impl/impl.h
index 54c31deb4..bf7d1bae8 100644
--- a/src/shader_recompiler/frontend/maxwell/translate/impl/impl.h
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/impl.h
@@ -353,6 +353,7 @@ public:
     [[nodiscard]] IR::U32 GetReg8(u64 insn);
     [[nodiscard]] IR::U32 GetReg20(u64 insn);
     [[nodiscard]] IR::U32 GetReg39(u64 insn);
+    [[nodiscard]] IR::F32 GetFloatReg8(u64 insn);
     [[nodiscard]] IR::F32 GetFloatReg20(u64 insn);
     [[nodiscard]] IR::F32 GetFloatReg39(u64 insn);
     [[nodiscard]] IR::F64 GetDoubleReg20(u64 insn);
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 a0057a473..6a580f831 100644
--- a/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
+++ b/src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp
@@ -89,10 +89,6 @@ void TranslatorVisitor::FCHK_imm(u64) {
     ThrowNotImplemented(Opcode::FCHK_imm);
 }
 
-void TranslatorVisitor::FSWZADD(u64) {
-    ThrowNotImplemented(Opcode::FSWZADD);
-}
-
 void TranslatorVisitor::GETCRSPTR(u64) {
     ThrowNotImplemented(Opcode::GETCRSPTR);
 }
diff --git a/src/shader_recompiler/ir_opt/collect_shader_info_pass.cpp b/src/shader_recompiler/ir_opt/collect_shader_info_pass.cpp
index c932c307b..81090335f 100644
--- a/src/shader_recompiler/ir_opt/collect_shader_info_pass.cpp
+++ b/src/shader_recompiler/ir_opt/collect_shader_info_pass.cpp
@@ -389,6 +389,9 @@ void VisitUsages(Info& info, IR::Inst& inst) {
     case IR::Opcode::SubgroupBallot:
         info.uses_subgroup_vote = true;
         break;
+    case IR::Opcode::FSwizzleAdd:
+        info.uses_fswzadd = true;
+        break;
     default:
         break;
     }
diff --git a/src/shader_recompiler/shader_info.h b/src/shader_recompiler/shader_info.h
index 9111159f3..4b4006b7f 100644
--- a/src/shader_recompiler/shader_info.h
+++ b/src/shader_recompiler/shader_info.h
@@ -94,6 +94,7 @@ struct Info {
     bool uses_sparse_residency{};
     bool uses_demote_to_helper_invocation{};
     bool uses_subgroup_vote{};
+    bool uses_fswzadd{};
 
     IR::Type used_constant_buffer_types{};