1 files changed, 322 insertions, 0 deletions
diff --git a/src/Ryujinx.Graphics.Shader/Instructions/InstEmitFlowControl.cs b/src/Ryujinx.Graphics.Shader/Instructions/InstEmitFlowControl.cs
new file mode 100644
index 00000000..91c23230
--- /dev/null
+++ b/src/Ryujinx.Graphics.Shader/Instructions/InstEmitFlowControl.cs
@@ -0,0 +1,322 @@
+using Ryujinx.Graphics.Shader.Decoders;
+using Ryujinx.Graphics.Shader.IntermediateRepresentation;
+using Ryujinx.Graphics.Shader.Translation;
+using System.Collections.Generic;
+using System.Linq;
+
+using static Ryujinx.Graphics.Shader.Instructions.InstEmitHelper;
+using static Ryujinx.Graphics.Shader.IntermediateRepresentation.OperandHelper;
+
+namespace Ryujinx.Graphics.Shader.Instructions
+{
+    static partial class InstEmit
+    {
+        public static void Bra(EmitterContext context)
+        {
+            InstBra op = context.GetOp<InstBra>();
+
+            EmitBranch(context, context.CurrBlock.Successors[^1].Address);
+        }
+
+        public static void Brk(EmitterContext context)
+        {
+            InstBrk op = context.GetOp<InstBrk>();
+
+            EmitBrkContSync(context);
+        }
+
+        public static void Brx(EmitterContext context)
+        {
+            InstBrx op = context.GetOp<InstBrx>();
+            InstOp currOp = context.CurrOp;
+            int startIndex = context.CurrBlock.HasNext() ? 1 : 0;
+
+            if (context.CurrBlock.Successors.Count <= startIndex)
+            {
+                context.Config.GpuAccessor.Log($"Failed to find targets for BRX instruction at 0x{currOp.Address:X}.");
+                return;
+            }
+
+            int offset = (int)currOp.GetAbsoluteAddress();
+
+            Operand address = context.IAdd(Register(op.SrcA, RegisterType.Gpr), Const(offset));
+
+            var targets = context.CurrBlock.Successors.Skip(startIndex);
+
+            bool allTargetsSinglePred = true;
+            int total = context.CurrBlock.Successors.Count - startIndex;
+            int count = 0;
+
+            foreach (var target in targets.OrderBy(x => x.Address))
+            {
+                if (++count < total && (target.Predecessors.Count > 1 || target.Address <= context.CurrBlock.Address))
+                {
+                    allTargetsSinglePred = false;
+                    break;
+                }
+            }
+
+            if (allTargetsSinglePred)
+            {
+                // Chain blocks, each target block will check if the BRX target address
+                // matches its own address, if not, it jumps to the next target which will do the same check,
+                // until it reaches the last possible target, which executed unconditionally.
+                // We can only do this if the BRX block is the only predecessor of all target blocks.
+                // Additionally, this is not supported for blocks located before the current block,
+                // since it will be too late to insert a label, but this is something that can be improved
+                // in the future if necessary.
+
+                var sortedTargets = targets.OrderBy(x => x.Address);
+
+                Block currentTarget = null;
+                ulong firstTargetAddress = 0;
+
+                foreach (Block nextTarget in sortedTargets)
+                {
+                    if (currentTarget != null)
+                    {
+                        if (currentTarget.Address != nextTarget.Address)
+                        {
+                            context.SetBrxTarget(currentTarget.Address, address, (int)currentTarget.Address, nextTarget.Address);
+                        }
+                    }
+                    else
+                    {
+                        firstTargetAddress = nextTarget.Address;
+                    }
+
+                    currentTarget = nextTarget;
+                }
+
+                context.Branch(context.GetLabel(firstTargetAddress));
+            }
+            else
+            {
+                // Emit the branches sequentially.
+                // This generates slightly worse code, but should work for all cases.
+
+                var sortedTargets = targets.OrderByDescending(x => x.Address);
+                ulong lastTargetAddress = ulong.MaxValue;
+
+                count = 0;
+
+                foreach (Block target in sortedTargets)
+                {
+                    Operand label = context.GetLabel(target.Address);
+
+                    if (++count < total)
+                    {
+                        if (target.Address != lastTargetAddress)
+                        {
+                            context.BranchIfTrue(label, context.ICompareEqual(address, Const((int)target.Address)));
+                        }
+
+                        lastTargetAddress = target.Address;
+                    }
+                    else
+                    {
+                        context.Branch(label);
+                    }
+                }
+            }
+        }
+
+        public static void Cal(EmitterContext context)
+        {
+            InstCal op = context.GetOp<InstCal>();
+
+            DecodedFunction function = context.Program.GetFunctionByAddress(context.CurrOp.GetAbsoluteAddress());
+
+            if (function.IsCompilerGenerated)
+            {
+                switch (function.Type)
+                {
+                    case FunctionType.BuiltInFSIBegin:
+                        context.FSIBegin();
+                        break;
+                    case FunctionType.BuiltInFSIEnd:
+                        context.FSIEnd();
+                        break;
+                }
+            }
+            else
+            {
+                context.Call(function.Id, false);
+            }
+        }
+
+        public static void Cont(EmitterContext context)
+        {
+            InstCont op = context.GetOp<InstCont>();
+
+            EmitBrkContSync(context);
+        }
+
+        public static void Exit(EmitterContext context)
+        {
+            InstExit op = context.GetOp<InstExit>();
+
+            if (context.IsNonMain)
+            {
+                context.Config.GpuAccessor.Log("Invalid exit on non-main function.");
+                return;
+            }
+
+            if (op.Ccc == Ccc.T)
+            {
+                context.Return();
+            }
+            else
+            {
+                Operand cond = GetCondition(context, op.Ccc, IrConsts.False);
+
+                // If the condition is always false, we don't need to do anything.
+                if (cond.Type != OperandType.Constant || cond.Value != IrConsts.False)
+                {
+                    Operand lblSkip = Label();
+                    context.BranchIfFalse(lblSkip, cond);
+                    context.Return();
+                    context.MarkLabel(lblSkip);
+                }
+            }
+        }
+
+        public static void Kil(EmitterContext context)
+        {
+            InstKil op = context.GetOp<InstKil>();
+
+            context.Discard();
+        }
+
+        public static void Pbk(EmitterContext context)
+        {
+            InstPbk op = context.GetOp<InstPbk>();
+
+            EmitPbkPcntSsy(context);
+        }
+
+        public static void Pcnt(EmitterContext context)
+        {
+            InstPcnt op = context.GetOp<InstPcnt>();
+
+            EmitPbkPcntSsy(context);
+        }
+
+        public static void Ret(EmitterContext context)
+        {
+            InstRet op = context.GetOp<InstRet>();
+
+            if (context.IsNonMain)
+            {
+                context.Return();
+            }
+            else
+            {
+                context.Config.GpuAccessor.Log("Invalid return on main function.");
+            }
+        }
+
+        public static void Ssy(EmitterContext context)
+        {
+            InstSsy op = context.GetOp<InstSsy>();
+
+            EmitPbkPcntSsy(context);
+        }
+
+        public static void Sync(EmitterContext context)
+        {
+            InstSync op = context.GetOp<InstSync>();
+
+            EmitBrkContSync(context);
+        }
+
+        private static void EmitPbkPcntSsy(EmitterContext context)
+        {
+            var consumers = context.CurrBlock.PushOpCodes.First(x => x.Op.Address == context.CurrOp.Address).Consumers;
+
+            foreach (KeyValuePair<Block, Operand> kv in consumers)
+            {
+                Block consumerBlock = kv.Key;
+                Operand local = kv.Value;
+
+                int id = consumerBlock.SyncTargets[context.CurrOp.Address].PushOpId;
+
+                context.Copy(local, Const(id));
+            }
+        }
+
+        private static void EmitBrkContSync(EmitterContext context)
+        {
+            var targets = context.CurrBlock.SyncTargets;
+
+            if (targets.Count == 1)
+            {
+                // If we have only one target, then the SSY/PBK is basically
+                // a branch, we can produce better codegen for this case.
+                EmitBranch(context, targets.Values.First().PushOpInfo.Op.GetAbsoluteAddress());
+            }
+            else
+            {
+                // TODO: Support CC here as well (condition).
+                foreach (SyncTarget target in targets.Values)
+                {
+                    PushOpInfo pushOpInfo = target.PushOpInfo;
+
+                    Operand label = context.GetLabel(pushOpInfo.Op.GetAbsoluteAddress());
+                    Operand local = pushOpInfo.Consumers[context.CurrBlock];
+
+                    context.BranchIfTrue(label, context.ICompareEqual(local, Const(target.PushOpId)));
+                }
+            }
+        }
+
+        private static void EmitBranch(EmitterContext context, ulong address)
+        {
+            InstOp op = context.CurrOp;
+            InstConditional opCond = new InstConditional(op.RawOpCode);
+
+            // If we're branching to the next instruction, then the branch
+            // is useless and we can ignore it.
+            if (address == op.Address + 8)
+            {
+                return;
+            }
+
+            Operand label = context.GetLabel(address);
+
+            Operand pred = Register(opCond.Pred, RegisterType.Predicate);
+
+            if (opCond.Ccc != Ccc.T)
+            {
+                Operand cond = GetCondition(context, opCond.Ccc);
+
+                if (opCond.Pred == RegisterConsts.PredicateTrueIndex)
+                {
+                    pred = cond;
+                }
+                else if (opCond.PredInv)
+                {
+                    pred = context.BitwiseAnd(context.BitwiseNot(pred), cond);
+                }
+                else
+                {
+                    pred = context.BitwiseAnd(pred, cond);
+                }
+
+                context.BranchIfTrue(label, pred);
+            }
+            else if (opCond.Pred == RegisterConsts.PredicateTrueIndex)
+            {
+                context.Branch(label);
+            }
+            else if (opCond.PredInv)
+            {
+                context.BranchIfFalse(label, pred);
+            }
+            else
+            {
+                context.BranchIfTrue(label, pred);
+            }
+        }
+    }
+}
+\ No newline at end of file