shader: Fix control flow

src/shader_recompiler/frontend/ir/ir_emitter.cpp

@@ -134,18 +134,27 @@ void IREmitter::SetOFlag(const U1& value) {
     Inst(Opcode::SetOFlag, value);
 }
 
-U1 IREmitter::Condition(IR::Condition cond) {
-    if (cond == IR::Condition{true}) {
-        return Imm1(true);
-    } else if (cond == IR::Condition{false}) {
-        return Imm1(false);
+static U1 GetFlowTest(IREmitter& ir, FlowTest flow_test) {
+    switch (flow_test) {
+    case FlowTest::T:
+        return ir.Imm1(true);
+    case FlowTest::F:
+        return ir.Imm1(false);
+    case FlowTest::EQ:
+        // TODO: Test this
+        return ir.GetZFlag();
+    case FlowTest::NE:
+        // TODO: Test this
+        return ir.LogicalNot(ir.GetZFlag());
+    default:
+        throw NotImplementedException("Flow test {}", flow_test);
     }
+}
+
+U1 IREmitter::Condition(IR::Condition cond) {
     const FlowTest flow_test{cond.FlowTest()};
     const auto [pred, is_negated]{cond.Pred()};
-    if (flow_test == FlowTest::T) {
-        return GetPred(pred, is_negated);
-    }
-    throw NotImplementedException("Condition {}", cond);
+    return LogicalAnd(GetPred(pred, is_negated), GetFlowTest(*this, flow_test));
 }
 
 F32 IREmitter::GetAttribute(IR::Attribute attribute) {

src/shader_recompiler/frontend/ir/opcodes.inc

@@ -4,8 +4,8 @@
 
 //     opcode name,                                         return type,    arg1 type,      arg2 type,      arg3 type,      arg4 type,      ...
 OPCODE(Phi,                                                 Opaque,                                                                         )
-OPCODE(Void,                                                Void,                                                                           )
 OPCODE(Identity,                                            Opaque,         Opaque,                                                         )
+OPCODE(Void,                                                Void,                                                                           )
 
 // Control flow
 OPCODE(Branch,                                              Void,           Label,                                                          )

src/shader_recompiler/frontend/ir/structured_control_flow.cpp

@@ -329,7 +329,6 @@ private:
         if (!sibling) {
             throw LogicError("Not siblings");
         }
-
         // goto_stmt and label_stmt are guaranteed to be siblings, eliminate
         if (std::next(goto_stmt) == label_stmt) {
             // Simply eliminate the goto if the label is next to it
@@ -351,9 +350,14 @@ private:
         const std::unordered_map labels_map{BuildLabels(blocks)};
         Tree& root{root_stmt.children};
         auto insert_point{root.begin()};
+        // Skip all goto variables zero-initialization
+        std::advance(insert_point, labels_map.size());
+
         for (Block* const block : blocks) {
-            ++insert_point; // Skip label
-            ++insert_point; // Skip set variable
+            // Skip label
+            ++insert_point;
+            // Skip set variable
+            ++insert_point;
             root.insert(insert_point, *pool.Create(block, &root_stmt));
 
             if (block->IsTerminationBlock()) {
@@ -391,6 +395,7 @@ private:
             labels_map.emplace(block, root.insert(root.end(), *label));
             Statement* const false_stmt{pool.Create(Identity{}, Condition{false})};
             root.push_back(*pool.Create(SetVariable{}, label_id, false_stmt, &root_stmt));
+            root.push_front(*pool.Create(SetVariable{}, label_id, false_stmt, &root_stmt));
             ++label_id;
         }
         return labels_map;
@@ -457,10 +462,10 @@ private:
         }
         body.erase(goto_stmt);
 
-        // Update nested if condition
         switch (label_nested_stmt->type) {
         case StatementType::If:
-            label_nested_stmt->cond = pool.Create(Or{}, neg_var, label_nested_stmt->cond);
+            // Update nested if condition
+            label_nested_stmt->cond = pool.Create(Or{}, variable, label_nested_stmt->cond);
             break;
         case StatementType::Loop:
             break;

src/shader_recompiler/frontend/ir/value.cpp

@@ -36,6 +36,10 @@ bool Value::IsIdentity() const noexcept {
     return type == Type::Opaque && inst->Opcode() == Opcode::Identity;
 }
 
+bool Value::IsPhi() const noexcept {
+    return type == Type::Opaque && inst->Opcode() == Opcode::Phi;
+}
+
 bool Value::IsEmpty() const noexcept {
     return type == Type::Void;
 }
@@ -52,7 +56,7 @@ bool Value::IsLabel() const noexcept {
 }
 
 IR::Type Value::Type() const noexcept {
-    if (IsIdentity()) {
+    if (IsIdentity() || IsPhi()) {
         return inst->Arg(0).Type();
     }
     if (type == Type::Opaque) {

src/shader_recompiler/frontend/ir/value.h

@@ -33,6 +33,7 @@ public:
     explicit Value(f64 value) noexcept;
 
     [[nodiscard]] bool IsIdentity() const noexcept;
+    [[nodiscard]] bool IsPhi() const noexcept;
     [[nodiscard]] bool IsEmpty() const noexcept;
     [[nodiscard]] bool IsImmediate() const noexcept;
     [[nodiscard]] bool IsLabel() const noexcept;

src/shader_recompiler/frontend/maxwell/control_flow.cpp

@@ -354,7 +354,7 @@ void CFG::AnalyzeCondInst(Block* block, FunctionId function_id, Location pc,
     // Impersonate the visited block with a virtual block
     *block = std::move(virtual_block);
     // Set the end properties of the conditional instruction
-    conditional_block->end = pc;
+    conditional_block->end = pc + 1;
     conditional_block->end_class = insn_end_class;
     // Add a label to the instruction after the conditional instruction
     Block* const endif_block{AddLabel(conditional_block, block->stack, pc + 1, function_id)};

src/shader_recompiler/frontend/maxwell/translate/impl/impl.h

@@ -209,7 +209,7 @@ public:
     void P2R_cbuf(u64 insn);
     void P2R_imm(u64 insn);
     void PBK();
-    void PCNT(u64 insn);
+    void PCNT();
     void PEXIT(u64 insn);
     void PIXLD(u64 insn);
     void PLONGJMP(u64 insn);

src/shader_recompiler/frontend/maxwell/translate/impl/not_implemented.cpp

@@ -637,8 +637,8 @@ void TranslatorVisitor::PBK() {
     // PBK is a no-op
 }
 
-void TranslatorVisitor::PCNT(u64) {
-    ThrowNotImplemented(Opcode::PCNT);
+void TranslatorVisitor::PCNT() {
+    // PCNT is a no-op
 }
 
 void TranslatorVisitor::PEXIT(u64) {