RyuKen/ARMeilleure/Decoders/Block.cs
Ficture Seven 2421186d97
Generalize tail continues (#1298)
* Generalize tail continues

* Fix DecodeBasicBlock

`Next` and `Branch` would be null, which is not the state expected by
the branch instructions. They end up branching or falling into a block
which is never populated by the `Translator`. This causes an assert to
be fired when building the CFG.

* Clean up Decode overloads

* Do not synchronize when branching into exit block

If we're branching into an exit block, that exit block will tail
continue into another translation which already has a synchronization.

* Remove A32 predicate tail continue

If `block` is not an exit block then the `block.Next` must exist (as
per the last instruction of `block`).

* Throw if decoded 0 blocks

Address gdkchan's feedback

* Rebuild block list instead of setting to null

Address gdkchan's feedback
2020-06-18 13:37:21 +10:00

102 lines
No EOL
2.4 KiB
C#

using System;
using System.Collections.Generic;
namespace ARMeilleure.Decoders
{
class Block
{
public ulong Address { get; set; }
public ulong EndAddress { get; set; }
public Block Next { get; set; }
public Block Branch { get; set; }
public bool TailCall { get; set; }
public bool Exit { get; set; }
public List<OpCode> OpCodes { get; private set; }
public Block()
{
OpCodes = new List<OpCode>();
}
public Block(ulong address) : this()
{
Address = address;
}
public void Split(Block rightBlock)
{
int splitIndex = BinarySearch(OpCodes, rightBlock.Address);
if (OpCodes[splitIndex].Address < rightBlock.Address)
{
splitIndex++;
}
int splitCount = OpCodes.Count - splitIndex;
if (splitCount <= 0)
{
throw new ArgumentException("Can't split at right block address.");
}
rightBlock.EndAddress = EndAddress;
rightBlock.Next = Next;
rightBlock.Branch = Branch;
rightBlock.OpCodes.AddRange(OpCodes.GetRange(splitIndex, splitCount));
EndAddress = rightBlock.Address;
Next = rightBlock;
Branch = null;
OpCodes.RemoveRange(splitIndex, splitCount);
}
private static int BinarySearch(List<OpCode> opCodes, ulong address)
{
int left = 0;
int middle = 0;
int right = opCodes.Count - 1;
while (left <= right)
{
int size = right - left;
middle = left + (size >> 1);
OpCode opCode = opCodes[middle];
if (address == (ulong)opCode.Address)
{
break;
}
if (address < (ulong)opCode.Address)
{
right = middle - 1;
}
else
{
left = middle + 1;
}
}
return middle;
}
public OpCode GetLastOp()
{
if (OpCodes.Count > 0)
{
return OpCodes[OpCodes.Count - 1];
}
return null;
}
}
}