20 files changed, 163 insertions, 1 deletions

diff --git a/src/shader_recompiler/CMakeLists.txt b/src/shader_recompiler/CMakeLists.txt
index af8e51fe8..189e5cb17 100644
--- a/src/shader_recompiler/CMakeLists.txt
+++ b/src/shader_recompiler/CMakeLists.txt
@@ -224,6 +224,7 @@ add_library(shader_recompiler STATIC
     ir_opt/lower_fp16_to_fp32.cpp
     ir_opt/lower_int64_to_int32.cpp
     ir_opt/passes.h
+    ir_opt/position_pass.cpp
     ir_opt/rescaling_pass.cpp
     ir_opt/ssa_rewrite_pass.cpp
     ir_opt/texture_pass.cpp
diff --git a/src/shader_recompiler/backend/glasm/emit_glasm.cpp b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
index 97a6b383b..1419207e8 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm.cpp
@@ -450,6 +450,9 @@ std::string EmitGLASM(const Profile& profile, const RuntimeInfo& runtime_info, I
     if (program.info.uses_rescaling_uniform) {
         header += "PARAM scaling[1]={program.local[0..0]};";
     }
+    if (program.info.uses_render_area) {
+        header += "PARAM render_area[1]={program.local[1..1]};";
+    }
     header += "TEMP ";
     for (size_t index = 0; index < ctx.reg_alloc.NumUsedRegisters(); ++index) {
         header += fmt::format("R{},", index);
diff --git a/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp b/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp
index b5c08d611..ee0b0f53d 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm_context_get_set.cpp
@@ -379,6 +379,10 @@ void EmitResolutionDownFactor(EmitContext& ctx, IR::Inst& inst) {
     ctx.Add("MOV.F {}.x,scaling[0].z;", inst);
 }
 
+void EmitRenderArea(EmitContext& ctx, IR::Inst& inst) {
+    ctx.Add("MOV.F {},render_area[0];", inst);
+}
+
 void EmitLoadLocal(EmitContext& ctx, IR::Inst& inst, ScalarU32 word_offset) {
     ctx.Add("MOV.U {},lmem[{}].x;", inst, word_offset);
 }
diff --git a/src/shader_recompiler/backend/glasm/emit_glasm_instructions.h b/src/shader_recompiler/backend/glasm/emit_glasm_instructions.h
index 8b0ac3031..c08f48ed9 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm_instructions.h
+++ b/src/shader_recompiler/backend/glasm/emit_glasm_instructions.h
@@ -73,6 +73,7 @@ void EmitSampleId(EmitContext& ctx, IR::Inst& inst);
 void EmitIsHelperInvocation(EmitContext& ctx, IR::Inst& inst);
 void EmitYDirection(EmitContext& ctx, IR::Inst& inst);
 void EmitResolutionDownFactor(EmitContext& ctx, IR::Inst& inst);
+void EmitRenderArea(EmitContext& ctx, IR::Inst& inst);
 void EmitLoadLocal(EmitContext& ctx, IR::Inst& inst, ScalarU32 word_offset);
 void EmitWriteLocal(EmitContext& ctx, ScalarU32 word_offset, ScalarU32 value);
 void EmitUndefU1(EmitContext& ctx, IR::Inst& inst);
diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp b/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
index fad8d1e30..d7c845469 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_context_get_set.cpp
@@ -416,6 +416,10 @@ void EmitResolutionDownFactor(EmitContext& ctx, IR::Inst& inst) {
     ctx.AddF32("{}=scaling.z;", inst);
 }
 
+void EmitRenderArea(EmitContext& ctx, IR::Inst& inst) {
+    ctx.AddF32x4("{}=render_area;", inst);
+}
+
 void EmitLoadLocal(EmitContext& ctx, IR::Inst& inst, std::string_view word_offset) {
     ctx.AddU32("{}=lmem[{}];", inst, word_offset);
 }
diff --git a/src/shader_recompiler/backend/glsl/emit_glsl_instructions.h b/src/shader_recompiler/backend/glsl/emit_glsl_instructions.h
index 639691ba6..3c8bcb7e9 100644
--- a/src/shader_recompiler/backend/glsl/emit_glsl_instructions.h
+++ b/src/shader_recompiler/backend/glsl/emit_glsl_instructions.h
@@ -87,6 +87,7 @@ void EmitSampleId(EmitContext& ctx, IR::Inst& inst);
 void EmitIsHelperInvocation(EmitContext& ctx, IR::Inst& inst);
 void EmitYDirection(EmitContext& ctx, IR::Inst& inst);
 void EmitResolutionDownFactor(EmitContext& ctx, IR::Inst& inst);
+void EmitRenderArea(EmitContext& ctx, IR::Inst& inst);
 void EmitLoadLocal(EmitContext& ctx, IR::Inst& inst, std::string_view word_offset);
 void EmitWriteLocal(EmitContext& ctx, std::string_view word_offset, std::string_view value);
 void EmitUndefU1(EmitContext& ctx, IR::Inst& inst);
diff --git a/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp b/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp
index c767a9dc3..5d01ec0cd 100644
--- a/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp
+++ b/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp
@@ -358,6 +358,9 @@ EmitContext::EmitContext(IR::Program& program, Bindings& bindings, const Profile
     if (info.uses_rescaling_uniform) {
         header += "layout(location=0) uniform vec4 scaling;";
     }
+    if (info.uses_render_area) {
+        header += "layout(location=1) uniform vec4 render_area;";
+    }
     DefineConstantBuffers(bindings);
     DefineConstantBufferIndirect();
     DefineStorageBuffers(bindings);
diff --git a/src/shader_recompiler/backend/spirv/emit_spirv.h b/src/shader_recompiler/backend/spirv/emit_spirv.h
index 7567b6fc9..937881484 100644
--- a/src/shader_recompiler/backend/spirv/emit_spirv.h
+++ b/src/shader_recompiler/backend/spirv/emit_spirv.h
@@ -23,8 +23,12 @@ struct RescalingLayout {
     alignas(16) std::array<u32, NUM_IMAGE_SCALING_WORDS> rescaling_images;
     u32 down_factor;
 };
+struct RenderAreaLayout {
+    std::array<f32, 4> render_area;
+};
 constexpr u32 RESCALING_LAYOUT_WORDS_OFFSET = offsetof(RescalingLayout, rescaling_textures);
 constexpr u32 RESCALING_LAYOUT_DOWN_FACTOR_OFFSET = offsetof(RescalingLayout, down_factor);
+constexpr u32 RENDERAREA_LAYOUT_OFFSET = offsetof(RenderAreaLayout, render_area);
 
 [[nodiscard]] std::vector<u32> EmitSPIRV(const Profile& profile, const RuntimeInfo& runtime_info,
                                          IR::Program& program, Bindings& bindings);
diff --git a/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp b/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp
index 2c68aba39..a4751b42d 100644
--- a/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp
+++ b/src/shader_recompiler/backend/spirv/emit_spirv_context_get_set.cpp
@@ -353,7 +353,6 @@ Id EmitGetAttribute(EmitContext& ctx, IR::Attribute attr, Id vertex) {
     case IR::Attribute::TessellationEvaluationPointV:
         return ctx.OpLoad(ctx.F32[1],
                           ctx.OpAccessChain(ctx.input_f32, ctx.tess_coord, ctx.Const(1U)));
-
     default:
         throw NotImplementedException("Read attribute {}", attr);
     }
@@ -537,6 +536,17 @@ Id EmitResolutionDownFactor(EmitContext& ctx) {
     }
 }
 
+Id EmitRenderArea(EmitContext& ctx) {
+    if (ctx.profile.unified_descriptor_binding) {
+        const Id pointer_type{ctx.TypePointer(spv::StorageClass::PushConstant, ctx.F32[4])};
+        const Id index{ctx.Const(ctx.render_are_member_index)};
+        const Id pointer{ctx.OpAccessChain(pointer_type, ctx.render_area_push_constant, index)};
+        return ctx.OpLoad(ctx.F32[4], pointer);
+    } else {
+        throw NotImplementedException("SPIR-V Instruction");
+    }
+}
+
 Id EmitLoadLocal(EmitContext& ctx, Id word_offset) {
     const Id pointer{ctx.OpAccessChain(ctx.private_u32, ctx.local_memory, word_offset)};
     return ctx.OpLoad(ctx.U32[1], pointer);
diff --git a/src/shader_recompiler/backend/spirv/emit_spirv_instructions.h b/src/shader_recompiler/backend/spirv/emit_spirv_instructions.h
index 984d072b4..86dd3c4f3 100644
--- a/src/shader_recompiler/backend/spirv/emit_spirv_instructions.h
+++ b/src/shader_recompiler/backend/spirv/emit_spirv_instructions.h
@@ -76,6 +76,7 @@ Id EmitSampleId(EmitContext& ctx);
 Id EmitIsHelperInvocation(EmitContext& ctx);
 Id EmitYDirection(EmitContext& ctx);
 Id EmitResolutionDownFactor(EmitContext& ctx);
+Id EmitRenderArea(EmitContext& ctx);
 Id EmitLoadLocal(EmitContext& ctx, Id word_offset);
 void EmitWriteLocal(EmitContext& ctx, Id word_offset, Id value);
 Id EmitUndefU1(EmitContext& ctx);
diff --git a/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp b/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
index aecc4c612..c26ad8f93 100644
--- a/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
+++ b/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
@@ -473,6 +473,7 @@ EmitContext::EmitContext(const Profile& profile_, const RuntimeInfo& runtime_inf
     DefineAttributeMemAccess(program.info);
     DefineGlobalMemoryFunctions(program.info);
     DefineRescalingInput(program.info);
+    DefineRenderArea(program.info);
 }
 
 EmitContext::~EmitContext() = default;
@@ -982,6 +983,36 @@ void EmitContext::DefineRescalingInputUniformConstant() {
     }
 }
 
+void EmitContext::DefineRenderArea(const Info& info) {
+    if (!info.uses_render_area) {
+        return;
+    }
+
+    if (profile.unified_descriptor_binding) {
+        boost::container::static_vector<Id, 1> members{};
+        u32 member_index{0};
+
+        members.push_back(F32[4]);
+        render_are_member_index = member_index++;
+
+        const Id push_constant_struct{TypeStruct(std::span(members.data(), members.size()))};
+        Decorate(push_constant_struct, spv::Decoration::Block);
+        Name(push_constant_struct, "RenderAreaInfo");
+
+        MemberDecorate(push_constant_struct, render_are_member_index, spv::Decoration::Offset, 0);
+        MemberName(push_constant_struct, render_are_member_index, "render_area");
+
+        const Id pointer_type{TypePointer(spv::StorageClass::PushConstant, push_constant_struct)};
+        render_area_push_constant =
+            AddGlobalVariable(pointer_type, spv::StorageClass::PushConstant);
+        Name(render_area_push_constant, "render_area_push_constants");
+
+        if (profile.supported_spirv >= 0x00010400) {
+            interfaces.push_back(render_area_push_constant);
+        }
+    }
+}
+
 void EmitContext::DefineConstantBuffers(const Info& info, u32& binding) {
     if (info.constant_buffer_descriptors.empty()) {
         return;
diff --git a/src/shader_recompiler/backend/spirv/spirv_emit_context.h b/src/shader_recompiler/backend/spirv/spirv_emit_context.h
index bc25b8b84..c86e50911 100644
--- a/src/shader_recompiler/backend/spirv/spirv_emit_context.h
+++ b/src/shader_recompiler/backend/spirv/spirv_emit_context.h
@@ -243,6 +243,9 @@ public:
     u32 texture_rescaling_index{};
     u32 image_rescaling_index{};
 
+    Id render_area_push_constant{};
+    u32 render_are_member_index{};
+
     Id local_memory{};
 
     Id shared_memory_u8{};
@@ -318,6 +321,7 @@ private:
     void DefineRescalingInput(const Info& info);
     void DefineRescalingInputPushConstant();
     void DefineRescalingInputUniformConstant();
+    void DefineRenderArea(const Info& info);
 
     void DefineInputs(const IR::Program& program);
     void DefineOutputs(const IR::Program& program);
diff --git a/src/shader_recompiler/environment.h b/src/shader_recompiler/environment.h
index 9729d48c6..980e0e54c 100644
--- a/src/shader_recompiler/environment.h
+++ b/src/shader_recompiler/environment.h
@@ -22,6 +22,8 @@ public:
 
     [[nodiscard]] virtual TextureType ReadTextureType(u32 raw_handle) = 0;
 
+    [[nodiscard]] virtual u32 ReadViewportTransformState() = 0;
+
     [[nodiscard]] virtual u32 TextureBoundBuffer() const = 0;
 
     [[nodiscard]] virtual u32 LocalMemorySize() const = 0;
diff --git a/src/shader_recompiler/frontend/ir/ir_emitter.cpp b/src/shader_recompiler/frontend/ir/ir_emitter.cpp
index 11086ed8c..de1ce90a3 100644
--- a/src/shader_recompiler/frontend/ir/ir_emitter.cpp
+++ b/src/shader_recompiler/frontend/ir/ir_emitter.cpp
@@ -378,6 +378,14 @@ F32 IREmitter::ResolutionDownFactor() {
     return Inst<F32>(Opcode::ResolutionDownFactor);
 }
 
+F32 IREmitter::RenderAreaWidth() {
+    return F32(CompositeExtract(Inst<Value>(Opcode::RenderArea), 0));
+}
+
+F32 IREmitter::RenderAreaHeight() {
+    return F32(CompositeExtract(Inst<Value>(Opcode::RenderArea), 1));
+}
+
 U32 IREmitter::LaneId() {
     return Inst<U32>(Opcode::LaneId);
 }
diff --git a/src/shader_recompiler/frontend/ir/ir_emitter.h b/src/shader_recompiler/frontend/ir/ir_emitter.h
index 25839a371..f163c18d9 100644
--- a/src/shader_recompiler/frontend/ir/ir_emitter.h
+++ b/src/shader_recompiler/frontend/ir/ir_emitter.h
@@ -103,6 +103,9 @@ public:
 
     [[nodiscard]] F32 ResolutionDownFactor();
 
+    [[nodiscard]] F32 RenderAreaWidth();
+    [[nodiscard]] F32 RenderAreaHeight();
+
     [[nodiscard]] U32 LaneId();
 
     [[nodiscard]] U32 LoadGlobalU8(const U64& address);
diff --git a/src/shader_recompiler/frontend/ir/opcodes.inc b/src/shader_recompiler/frontend/ir/opcodes.inc
index 86410ddfc..f3038f298 100644
--- a/src/shader_recompiler/frontend/ir/opcodes.inc
+++ b/src/shader_recompiler/frontend/ir/opcodes.inc
@@ -63,6 +63,7 @@ OPCODE(SampleId,                                            U32,
 OPCODE(IsHelperInvocation,                                  U1,                                                                                             )
 OPCODE(YDirection,                                          F32,                                                                                            )
 OPCODE(ResolutionDownFactor,                                F32,                                                                                            )
+OPCODE(RenderArea,                                          F32x4,                                                                                          )
 
 // Undefined
 OPCODE(UndefU1,                                             U1,                                                                                             )
diff --git a/src/shader_recompiler/frontend/maxwell/translate_program.cpp b/src/shader_recompiler/frontend/maxwell/translate_program.cpp
index 77efb4f57..dafb9deee 100644
--- a/src/shader_recompiler/frontend/maxwell/translate_program.cpp
+++ b/src/shader_recompiler/frontend/maxwell/translate_program.cpp
@@ -213,6 +213,8 @@ IR::Program TranslateProgram(ObjectPool<IR::Inst>& inst_pool, ObjectPool<IR::Blo
 
     Optimization::ConstantPropagationPass(program);
 
+    Optimization::PositionPass(env, program);
+
     Optimization::GlobalMemoryToStorageBufferPass(program);
     Optimization::TexturePass(env, program);
 
diff --git a/src/shader_recompiler/ir_opt/passes.h b/src/shader_recompiler/ir_opt/passes.h
index 6ff8e4266..24f609d69 100644
--- a/src/shader_recompiler/ir_opt/passes.h
+++ b/src/shader_recompiler/ir_opt/passes.h
@@ -17,6 +17,7 @@ void LowerFp16ToFp32(IR::Program& program);
 void LowerInt64ToInt32(IR::Program& program);
 void RescalingPass(IR::Program& program);
 void SsaRewritePass(IR::Program& program);
+void PositionPass(Environment& env, IR::Program& program);
 void TexturePass(Environment& env, IR::Program& program);
 void VerificationPass(const IR::Program& program);
 
diff --git a/src/shader_recompiler/ir_opt/position_pass.cpp b/src/shader_recompiler/ir_opt/position_pass.cpp
new file mode 100644
index 000000000..3c20b7189
--- /dev/null
+++ b/src/shader_recompiler/ir_opt/position_pass.cpp
@@ -0,0 +1,77 @@
+// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <boost/container/small_vector.hpp>
+
+#include "shader_recompiler/frontend/ir/basic_block.h"
+#include "shader_recompiler/frontend/ir/ir_emitter.h"
+#include "shader_recompiler/frontend/ir/value.h"
+#include "shader_recompiler/ir_opt/passes.h"
+
+namespace Shader::Optimization {
+
+namespace {
+struct PositionInst {
+    IR::Inst* inst;
+    IR::Block* block;
+    IR::Attribute attr;
+};
+using PositionInstVector = boost::container::small_vector<PositionInst, 24>;
+} // Anonymous namespace
+
+void PositionPass(Environment& env, IR::Program& program) {
+    if (env.ShaderStage() != Stage::VertexB || env.ReadViewportTransformState()) {
+        return;
+    }
+
+    Info& info{program.info};
+    info.uses_render_area = true;
+
+    PositionInstVector to_replace;
+    for (IR::Block* const block : program.post_order_blocks) {
+        for (IR::Inst& inst : block->Instructions()) {
+            switch (inst.GetOpcode()) {
+            case IR::Opcode::SetAttribute: {
+                const IR::Attribute attr{inst.Arg(0).Attribute()};
+                switch (attr) {
+                case IR::Attribute::PositionX:
+                case IR::Attribute::PositionY: {
+                    to_replace.push_back(PositionInst{.inst = &inst, .block = block, .attr = attr});
+                    break;
+                }
+                default:
+                    break;
+                }
+                break;
+            }
+            default:
+                break;
+            }
+        }
+    }
+
+    for (PositionInst& position_inst : to_replace) {
+        IR::IREmitter ir{*position_inst.block,
+                         IR::Block::InstructionList::s_iterator_to(*position_inst.inst)};
+        const IR::F32 value(position_inst.inst->Arg(1));
+        const IR::F32F64 scale(ir.Imm32(2.f));
+        const IR::F32 negative_one{ir.Imm32(-1.f)};
+        switch (position_inst.attr) {
+        case IR::Attribute::PositionX: {
+            position_inst.inst->SetArg(
+                1,
+                ir.FPFma(value, ir.FPMul(ir.FPRecip(ir.RenderAreaWidth()), scale), negative_one));
+            break;
+        }
+        case IR::Attribute::PositionY: {
+            position_inst.inst->SetArg(
+                1,
+                ir.FPFma(value, ir.FPMul(ir.FPRecip(ir.RenderAreaHeight()), scale), negative_one));
+            break;
+        }
+        default:
+            break;
+        }
+    }
+}
+} // namespace Shader::Optimization
diff --git a/src/shader_recompiler/shader_info.h b/src/shader_recompiler/shader_info.h
index f5690805c..e4b5ba567 100644
--- a/src/shader_recompiler/shader_info.h
+++ b/src/shader_recompiler/shader_info.h
@@ -175,6 +175,7 @@ struct Info {
     bool uses_shadow_lod{};
     bool uses_rescaling_uniform{};
     bool uses_cbuf_indirect{};
+    bool uses_render_area{};
 
     IR::Type used_constant_buffer_types{};
     IR::Type used_storage_buffer_types{};