Ryujinx/ARMeilleure/Translation/JitUnwindWindows.cs
LDj3SNuD 3b70a28087
Unwinding Follow-up. Fix a bug in JitUnwindWindows where ... (#1238)
... in case of "Vector" unwind codes the remaining unwind codes could be corrupted.
Nits.
2020-05-15 13:46:35 +02:00

188 lines
6.9 KiB
C#

// https://github.com/MicrosoftDocs/cpp-docs/blob/master/docs/build/exception-handling-x64.md
using ARMeilleure.CodeGen.Unwinding;
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
namespace ARMeilleure.Translation
{
static class JitUnwindWindows
{
private const int MaxUnwindCodesArraySize = 32; // Must be an even value.
private struct RuntimeFunction
{
public uint BeginAddress;
public uint EndAddress;
public uint UnwindData;
}
private struct UnwindInfo
{
public byte VersionAndFlags;
public byte SizeOfProlog;
public byte CountOfUnwindCodes;
public byte FrameRegister;
public unsafe fixed ushort UnwindCodes[MaxUnwindCodesArraySize];
}
private enum UnwindOperation
{
PushNonvol = 0,
AllocLarge = 1,
AllocSmall = 2,
SetFpreg = 3,
SaveNonvol = 4,
SaveNonvolFar = 5,
SaveXmm128 = 8,
SaveXmm128Far = 9,
PushMachframe = 10
}
private unsafe delegate RuntimeFunction* GetRuntimeFunctionCallback(ulong controlPc, IntPtr context);
[DllImport("kernel32.dll", CharSet = CharSet.Unicode)]
private static unsafe extern bool RtlInstallFunctionTableCallback(
ulong tableIdentifier,
ulong baseAddress,
uint length,
GetRuntimeFunctionCallback callback,
IntPtr context,
string outOfProcessCallbackDll);
private static GetRuntimeFunctionCallback _getRuntimeFunctionCallback;
private static int _sizeOfRuntimeFunction;
private unsafe static RuntimeFunction* _runtimeFunction;
private unsafe static UnwindInfo* _unwindInfo;
public static void InstallFunctionTableHandler(IntPtr codeCachePointer, uint codeCacheLength)
{
ulong codeCachePtr = (ulong)codeCachePointer.ToInt64();
_sizeOfRuntimeFunction = Marshal.SizeOf<RuntimeFunction>();
bool result;
unsafe
{
_runtimeFunction = (RuntimeFunction*)codeCachePointer;
_unwindInfo = (UnwindInfo*)(codeCachePointer + _sizeOfRuntimeFunction);
_getRuntimeFunctionCallback = new GetRuntimeFunctionCallback(FunctionTableHandler);
result = RtlInstallFunctionTableCallback(
codeCachePtr | 3,
codeCachePtr,
codeCacheLength,
_getRuntimeFunctionCallback,
codeCachePointer,
null);
}
if (!result)
{
throw new InvalidOperationException("Failure installing function table callback.");
}
}
private static unsafe RuntimeFunction* FunctionTableHandler(ulong controlPc, IntPtr context)
{
int offset = (int)((long)controlPc - context.ToInt64());
if (!JitCache.TryFind(offset, out JitCacheEntry funcEntry))
{
return null; // Not found.
}
var unwindInfo = funcEntry.UnwindInfo;
int codeIndex = 0;
for (int index = unwindInfo.PushEntries.Length - 1; index >= 0; index--)
{
var entry = unwindInfo.PushEntries[index];
switch (entry.PseudoOp)
{
case UnwindPseudoOp.SaveXmm128:
{
int stackOffset = entry.StackOffsetOrAllocSize;
Debug.Assert(stackOffset % 16 == 0);
if (stackOffset <= 0xFFFF0)
{
_unwindInfo->UnwindCodes[codeIndex++] = PackUnwindOp(UnwindOperation.SaveXmm128, entry.PrologOffset, entry.RegIndex);
_unwindInfo->UnwindCodes[codeIndex++] = (ushort)(stackOffset / 16);
}
else
{
_unwindInfo->UnwindCodes[codeIndex++] = PackUnwindOp(UnwindOperation.SaveXmm128Far, entry.PrologOffset, entry.RegIndex);
_unwindInfo->UnwindCodes[codeIndex++] = (ushort)(stackOffset >> 0);
_unwindInfo->UnwindCodes[codeIndex++] = (ushort)(stackOffset >> 16);
}
break;
}
case UnwindPseudoOp.AllocStack:
{
int allocSize = entry.StackOffsetOrAllocSize;
Debug.Assert(allocSize % 8 == 0);
if (allocSize <= 128)
{
_unwindInfo->UnwindCodes[codeIndex++] = PackUnwindOp(UnwindOperation.AllocSmall, entry.PrologOffset, (allocSize / 8) - 1);
}
else if (allocSize <= 0x7FFF8)
{
_unwindInfo->UnwindCodes[codeIndex++] = PackUnwindOp(UnwindOperation.AllocLarge, entry.PrologOffset, 0);
_unwindInfo->UnwindCodes[codeIndex++] = (ushort)(allocSize / 8);
}
else
{
_unwindInfo->UnwindCodes[codeIndex++] = PackUnwindOp(UnwindOperation.AllocLarge, entry.PrologOffset, 1);
_unwindInfo->UnwindCodes[codeIndex++] = (ushort)(allocSize >> 0);
_unwindInfo->UnwindCodes[codeIndex++] = (ushort)(allocSize >> 16);
}
break;
}
case UnwindPseudoOp.PushReg:
{
_unwindInfo->UnwindCodes[codeIndex++] = PackUnwindOp(UnwindOperation.PushNonvol, entry.PrologOffset, entry.RegIndex);
break;
}
default: throw new NotImplementedException($"({nameof(entry.PseudoOp)} = {entry.PseudoOp})");
}
}
Debug.Assert(codeIndex <= MaxUnwindCodesArraySize);
_unwindInfo->VersionAndFlags = 1; // Flags: The function has no handler.
_unwindInfo->SizeOfProlog = (byte)unwindInfo.PrologSize;
_unwindInfo->CountOfUnwindCodes = (byte)codeIndex;
_unwindInfo->FrameRegister = 0;
_runtimeFunction->BeginAddress = (uint)funcEntry.Offset;
_runtimeFunction->EndAddress = (uint)(funcEntry.Offset + funcEntry.Size);
_runtimeFunction->UnwindData = (uint)_sizeOfRuntimeFunction;
return _runtimeFunction;
}
private static ushort PackUnwindOp(UnwindOperation op, int prologOffset, int opInfo)
{
return (ushort)(prologOffset | ((int)op << 8) | (opInfo << 12));
}
}
}