Ryujinx/Ryujinx.Graphics.Shader/Instructions/InstEmitFlow.cs
gdkchan d9d18439f6
Use a new approach for shader BRX targets (#2532)
* Use a new approach for shader BRX targets

* Make shader cache actually work

* Improve the shader pattern matching a bit

* Extend LDC search to predecessor blocks, catches more cases

* Nit

* Only save the amount of constant buffer data actually used. Avoids crashes on partially mapped buffers

* Ignore Rd on predicate instructions, as they do not have a Rd register (catches more cases)
2021-08-11 20:59:42 +02:00

235 lines
7 KiB
C#

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)
{
EmitBranch(context, context.CurrBlock.Branch.Address);
}
public static void Brk(EmitterContext context)
{
EmitBrkOrSync(context);
}
public static void Brx(EmitterContext context)
{
OpCodeBranchIndir op = (OpCodeBranchIndir)context.CurrOp;
if (op.PossibleTargets.Count == 0)
{
context.Config.GpuAccessor.Log($"Failed to find targets for BRX instruction at 0x{op.Address:X}.");
return;
}
int offset = (int)op.Address + 8 + op.Offset;
Operand address = context.IAdd(Register(op.Ra), Const(offset));
// Sorting the target addresses in descending order improves the code,
// since it will always check the most distant targets first, then the
// near ones. This can be easily transformed into if/else statements.
IOrderedEnumerable<Block> sortedTargets = op.PossibleTargets.OrderByDescending(x => x.Address);
Block lastTarget = sortedTargets.LastOrDefault();
foreach (Block possibleTarget in sortedTargets)
{
Operand label = context.GetLabel(possibleTarget.Address);
if (possibleTarget != lastTarget)
{
context.BranchIfTrue(label, context.ICompareEqual(address, Const((int)possibleTarget.Address)));
}
else
{
context.Branch(label);
}
}
}
public static void Cal(EmitterContext context)
{
OpCodeBranch op = (OpCodeBranch)context.CurrOp;
context.Call(context.GetFunctionId(op.GetAbsoluteAddress()), false);
}
public static void Depbar(EmitterContext context)
{
}
public static void Exit(EmitterContext context)
{
if (context.IsNonMain)
{
context.Config.GpuAccessor.Log("Invalid exit on non-main function.");
return;
}
OpCodeExit op = (OpCodeExit)context.CurrOp;
// TODO: Figure out how this is supposed to work in the
// presence of other condition codes.
if (op.Condition == Condition.Always)
{
context.Return();
}
}
public static void Kil(EmitterContext context)
{
context.Discard();
}
public static void Nop(EmitterContext context)
{
}
public static void Pbk(EmitterContext context)
{
EmitPbkOrSsy(context);
}
public static void Ret(EmitterContext context)
{
if (context.IsNonMain)
{
context.Return();
}
else
{
context.Config.GpuAccessor.Log("Invalid return on main function.");
}
}
public static void Ssy(EmitterContext context)
{
EmitPbkOrSsy(context);
}
public static void Sync(EmitterContext context)
{
EmitBrkOrSync(context);
}
private static void EmitPbkOrSsy(EmitterContext context)
{
OpCodePush op = (OpCodePush)context.CurrOp;
foreach (KeyValuePair<OpCodeBranchPop, Operand> kv in op.PopOps)
{
OpCodeBranchPop opSync = kv.Key;
Operand local = kv.Value;
int pushOpIndex = opSync.Targets[op];
context.Copy(local, Const(pushOpIndex));
}
}
private static void EmitBrkOrSync(EmitterContext context)
{
OpCodeBranchPop op = (OpCodeBranchPop)context.CurrOp;
if (op.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.
OpCodePush pushOp = op.Targets.Keys.First();
EmitBranch(context, pushOp.GetAbsoluteAddress());
}
else
{
// TODO: Support CC here aswell (condition).
foreach (KeyValuePair<OpCodePush, int> kv in op.Targets)
{
OpCodePush pushOp = kv.Key;
Operand label = context.GetLabel(pushOp.GetAbsoluteAddress());
Operand local = pushOp.PopOps[op];
int pushOpIndex = kv.Value;
context.BranchIfTrue(label, context.ICompareEqual(local, Const(pushOpIndex)));
}
}
}
private static void EmitBranch(EmitterContext context, ulong address)
{
OpCode op = context.CurrOp;
// 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(op.Predicate);
if (op is OpCodeConditional opCond && opCond.Condition != Condition.Always)
{
Operand cond = GetCondition(context, opCond.Condition);
if (op.Predicate.IsPT)
{
pred = cond;
}
else if (op.InvertPredicate)
{
pred = context.BitwiseAnd(context.BitwiseNot(pred), cond);
}
else
{
pred = context.BitwiseAnd(pred, cond);
}
context.BranchIfTrue(label, pred);
}
else if (op.Predicate.IsPT)
{
context.Branch(label);
}
else if (op.InvertPredicate)
{
context.BranchIfFalse(label, pred);
}
else
{
context.BranchIfTrue(label, pred);
}
}
private static Operand GetCondition(EmitterContext context, Condition cond)
{
// TODO: More condition codes, figure out how they work.
switch (cond)
{
case Condition.Equal:
case Condition.EqualUnordered:
return GetZF();
case Condition.NotEqual:
case Condition.NotEqualUnordered:
return context.BitwiseNot(GetZF());
}
return Const(IrConsts.True);
}
}
}