Singularity/Library/PackageCache/com.unity.burst@1.8.4/Editor/BurstDisassembler.Core.cs
2024-05-06 11:45:45 -07:00

575 lines
21 KiB
C#

#if UNITY_EDITOR || BURST_INTERNAL
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Runtime.CompilerServices;
namespace Unity.Burst.Editor
{
internal partial class BurstDisassembler
{
/// <summary>
/// Base class for providing extended information of an identifier
/// </summary>
internal abstract class AsmTokenKindProvider
{
// Internally using string slice instead of string
// to support faster lookup from AsmToken
private readonly Dictionary<StringSlice, AsmTokenKind> _tokenKinds;
private int _maximumLength;
protected AsmTokenKindProvider(int capacity)
{
_tokenKinds = new Dictionary<StringSlice, AsmTokenKind>(capacity);
}
protected void AddTokenKind(string text, AsmTokenKind kind)
{
_tokenKinds.Add(new StringSlice(text), kind);
if (text.Length > _maximumLength) _maximumLength = text.Length;
}
public virtual AsmTokenKind FindTokenKind(StringSlice slice)
{
return slice.Length <= _maximumLength && _tokenKinds.TryGetValue(slice, out var tokenKind)
? tokenKind
: AsmTokenKind.Identifier;
}
public virtual bool AcceptsCharAsIdentifierOrRegisterEnd(char c)
{
return false;
}
public virtual bool IsInstructionOrRegisterOrIdentifier(char c)
{
// we include . because we have instructions like `b.le` or `f32.const`
return c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' || c == '_' ||
c == '@' || c == '.';
}
/// <summary>
/// Checks whether regA == regB. This function assumes the given strings are proper registers.
/// </summary>
public virtual bool RegisterEqual(string regA, string regB) => regA == regB;
public abstract SIMDkind SimdKind(StringSlice instruction);
}
/// <summary>
/// The ASM tokenizer
/// </summary>
private struct AsmTokenizer
{
private readonly string _text;
private readonly AsmKind _asmKind;
private readonly AsmTokenKindProvider _tokenKindProvider;
private int _position;
private int _nextPosition;
private int _alignedPosition;
private int _nextAlignedPosition;
private char _c;
private readonly char _commentStartChar;
private bool _doPad;
private int _padding;
public AsmTokenizer(string text, AsmKind asmKind, AsmTokenKindProvider tokenKindProvider, char commentStart)
{
_text = text;
_asmKind = asmKind;
_tokenKindProvider = tokenKindProvider;
_position = 0;
_nextPosition = 0;
_alignedPosition = 0;
_nextAlignedPosition = 0;
_commentStartChar = commentStart;
_doPad = false;
_padding = 0;
_c = (char)0;
NextChar();
}
public bool TryGetNextToken(out AsmToken token)
{
token = new AsmToken();
while (true)
{
var startPosition = _position;
var startAlignedPosition = _alignedPosition;
if (_c == 0)
{
return false;
}
if (_c == '.')
{
token = ParseDirective(startPosition, startAlignedPosition);
return true;
}
// Like everywhere else in this file, we are inlining the matching characters instead
// of using helper functions, as Mono might not be enough good at inlining by itself
if (_c >= 'a' && _c <= 'z' || _c >= 'A' && _c <= 'Z' || _c == '_' || _c == '@')
{
token = ParseInstructionOrIdentifierOrRegister(startPosition, startAlignedPosition);
PrepareAlignment(token);
return true;
}
if (_c >= '0' && _c <= '9' || _c == '-')
{
token = ParseNumber(startPosition, startAlignedPosition);
return true;
}
if (_c == '"')
{
token = ParseString(startPosition, startAlignedPosition);
return true;
}
if (_c == _commentStartChar)
{
token = ParseComment(startPosition, startAlignedPosition);
return true;
}
if (_c == '\r')
{
if (PreviewChar() == '\n')
{
NextChar(); // skip \r
}
token = ParseNewLine(startPosition, startAlignedPosition);
return true;
}
if (_c == '\n')
{
token = ParseNewLine(startPosition, startAlignedPosition);
return true;
}
if (_doPad)
{
_nextAlignedPosition += _padding;
_doPad = false;
}
token = ParseMisc(startPosition, startAlignedPosition);
return true;
}
}
private void PrepareAlignment(AsmToken token)
{
var kind = token.Kind;
_padding = InstructionAlignment - token.Length;
_doPad = _asmKind == AsmKind.Intel
&& (kind == AsmTokenKind.Instruction
|| kind == AsmTokenKind.BranchInstruction
|| kind == AsmTokenKind.CallInstruction
|| kind == AsmTokenKind.JumpInstruction
|| kind == AsmTokenKind.ReturnInstruction
|| kind == AsmTokenKind.InstructionSIMD)
&& _c != '\n' && _c != '\r' // If there is no registers behind instruction don't align.
&& _padding > 0;
}
private AsmToken ParseNewLine(int startPosition, int startAlignedPosition)
{
var endPosition = _position;
NextChar(); // Skip newline
return new AsmToken(AsmTokenKind.NewLine, startPosition, startAlignedPosition, endPosition - startPosition + 1);
}
private AsmToken ParseMisc(int startPosition, int startAlignedPosition)
{
var endPosition = _position;
// Parse anything that is not a directive, instruction, number, string or comment
while (!((_c == (char)0) || (_c == '\r') || (_c == '\n') || (_c == '.') || (_c >= 'a' && _c <= 'z' || _c >= 'A' && _c <= 'Z' || _c == '_' || _c == '@') || (_c >= '0' && _c <= '9' || _c == '-') || (_c == '"') || (_c == _commentStartChar)))
{
endPosition = _position;
NextChar();
}
return new AsmToken(AsmTokenKind.Misc, startPosition, startAlignedPosition, endPosition - startPosition + 1);
}
private static readonly string[] DataDirectiveStrings = new[]
{
AssertDataDirectiveLength(".long"),
AssertDataDirectiveLength(".byte"),
AssertDataDirectiveLength(".short"),
AssertDataDirectiveLength(".ascii"),
AssertDataDirectiveLength(".asciz"),
};
private static string AssertDataDirectiveLength(string text)
{
var length = text.Length;
Debug.Assert(length == 5 || length == 6, $"Invalid length {length} for string {text}. Expecting 5 or 6");
return text;
}
private AsmToken ParseDirective(int startPosition, int startAlignedPosition)
{
var endPosition = _position;
NextChar(); // skip .
bool isLabel = _c == 'L'; // A label starts with a capital `L` like .Lthis_is_a_jump_label
while (_c >= 'a' && _c <= 'z' || _c >= 'A' && _c <= 'Z' || _c >= '0' && _c <= '9' || _c == '.' || _c == '_' || _c == '@')
{
endPosition = _position;
NextChar();
}
// Refine the kind of directive:
//
// .Lfunc_begin => FunctionBegin
// .Lfunc_end => FunctionEnd
// .L????????? => Label
// data directive (.byte, .long, .short...) => DataDirective
// anything else => Directive
const string MatchFunc = ".Lfunc_";
const int MatchFuncLength = 7;
Debug.Assert(MatchFunc.Length == MatchFuncLength);
var kind = isLabel ? AsmTokenKind.Label : AsmTokenKind.Directive;
// Fast early check
if (isLabel && string.CompareOrdinal(_text, startPosition, MatchFunc, 0, MatchFuncLength) == 0)
{
if (string.CompareOrdinal(_text, startPosition, ".Lfunc_begin", 0, ".Lfunc_begin".Length) == 0)
{
kind = AsmTokenKind.FunctionBegin;
}
else if (string.CompareOrdinal(_text, startPosition, ".Lfunc_end", 0, ".Lfunc_end".Length) == 0)
{
kind = AsmTokenKind.FunctionEnd;
}
}
// Adjust directive to mark data directives, source location directives...etc.
int length = endPosition - startPosition + 1;
// Use length to early exit
if (!isLabel && length >= 4 && length <= 8)
{
if ((length == 5 || length == 6))
{
foreach (var dataDirectiveStr in DataDirectiveStrings)
{
if (string.CompareOrdinal(_text, startPosition, dataDirectiveStr, 0, dataDirectiveStr.Length) == 0)
{
kind = AsmTokenKind.DataDirective;
break;
}
}
// .file => SourceFile
if (kind == AsmTokenKind.Directive && string.CompareOrdinal(_text, startPosition, ".file", 0, 5) == 0)
{
kind = AsmTokenKind.SourceFile;
}
}
// .loc => SourceLocation
// .cv_loc => SourceLocation
else if ((length == 4 && string.CompareOrdinal(_text, startPosition, ".loc", 0, 4) == 0) ||
(length == 7 && string.CompareOrdinal(_text, startPosition, ".cv_loc", 0, 7) == 0))
{
kind = AsmTokenKind.SourceLocation;
}
// .file .cv_file => SourceFile
else if (length == 8 && string.CompareOrdinal(_text, startPosition, ".cv_file", 0, 8) == 0)
{
kind = AsmTokenKind.SourceFile;
}
}
return new AsmToken(kind, startPosition, startAlignedPosition, length);
}
private AsmToken ParseInstructionOrIdentifierOrRegister(int startPosition, int startAlignedPosition)
{
var endPosition = _position;
while (_tokenKindProvider.IsInstructionOrRegisterOrIdentifier(_c))
{
endPosition = _position;
NextChar();
}
if (_tokenKindProvider.AcceptsCharAsIdentifierOrRegisterEnd(_c))
{
endPosition = _position;
NextChar();
}
// Resolve token kind for identifier
int length = endPosition - startPosition + 1;
var tokenKind = _tokenKindProvider.FindTokenKind(new StringSlice(_text, startPosition, length));
if (tokenKind == AsmTokenKind.Identifier)
{
// If we have `:` right after an identifier, change from identifier to label declaration to help the semantic pass later
if (_c == ':')
{
tokenKind = AsmTokenKind.Label;
}
}
return new AsmToken(tokenKind, startPosition, startAlignedPosition, endPosition - startPosition + 1);
}
private AsmToken ParseNumber(int startPosition, int startAlignedPostion)
{
var endPosition = _position;
if (_c == '-')
{
NextChar();
}
while (_c >= '0' && _c <= '9' || _c >= 'a' && _c <= 'f' || _c >= 'A' && _c <= 'F' || _c == 'x' || _c == '.')
{
endPosition = _position;
NextChar();
}
// If we have `:` right after a number, change from number to label declaration to help the semantic pass later
var numberKind = _c == ':' ? AsmTokenKind.Label : AsmTokenKind.Number;
return new AsmToken(numberKind, startPosition, startAlignedPostion, endPosition - startPosition + 1);
}
private AsmToken ParseString(int startPosition, int startAlignedPostion)
{
var endPosition = _position;
// Skip first "
NextChar();
while (_c != (char)0 && _c != '"')
{
// Skip escape \"
if (_c == '\\' && PreviewChar() == '"')
{
NextChar();
}
endPosition = _position;
NextChar();
}
endPosition = _position;
NextChar(); // Skip trailing 0
// If we have `:` right after a string, change from string to label declaration to help the semantic pass later
var stringKind = _c == ':' ? AsmTokenKind.Label : AsmTokenKind.String;
return new AsmToken(stringKind, startPosition, startAlignedPostion, endPosition - startPosition + 1);
}
private AsmToken ParseComment(int startPosition, int startAlignedPosition)
{
var endPosition = _position;
while (_c != (char)0 && (_c != '\n' && _c != '\r'))
{
endPosition = _position;
NextChar();
}
return new AsmToken(AsmTokenKind.Comment, startPosition, startAlignedPosition, endPosition - startPosition + 1);
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private void NextChar()
{
if (_nextPosition < _text.Length)
{
_position = _nextPosition;
_c = _text[_position];
_nextPosition = _position + 1;
_alignedPosition = _nextAlignedPosition;
_nextAlignedPosition = _alignedPosition + 1;
}
else
{
_c = (char)0;
}
}
private char PreviewChar()
{
return _nextPosition < _text.Length ? _text[_nextPosition] : (char)0;
}
}
public enum SIMDkind
{
Packed,
Scalar,
Infrastructure,
}
/// <summary>
/// An ASM token. The token doesn't contain the string of the token, but provides method <see cref="Slice"/> and <see cref="ToString"/> to extract it.
/// </summary>
internal readonly struct AsmToken
{
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// CAUTION: It is important to not put *any managed objects*
// into this struct for GC efficiency
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
public AsmToken(AsmTokenKind kind, int position, int alignedPosition, int length)
{
Kind = kind;
Position = position;
AlignedPosition = alignedPosition;
Length = length;
}
public readonly AsmTokenKind Kind;
public readonly int Position;
public readonly int AlignedPosition;
public readonly int Length;
public StringSlice Slice(string text) => new StringSlice(text, Position, Length);
public string ToString(string text) => text.Substring(Position, Length);
public string ToFriendlyText(string text)
{
return $"{text.Substring(Position, Length)} : {Kind}";
}
}
/// <summary>
/// Kind of an ASM token.
/// </summary>
internal enum AsmTokenKind
{
Eof,
Directive,
DataDirective,
SourceFile,
SourceLocation,
Label,
FunctionBegin,
FunctionEnd,
Identifier,
Qualifier,
Instruction,
CallInstruction,
BranchInstruction,
JumpInstruction,
ReturnInstruction,
InstructionSIMD,
Register,
Number,
String,
Comment,
NewLine,
Misc
}
}
/// <summary>
/// A slice of a string from an original string.
/// </summary>
internal readonly struct StringSlice : IEquatable<StringSlice>
{
private readonly string _text;
public readonly int Position;
public readonly int Length;
public StringSlice(string text)
{
_text = text ?? throw new ArgumentNullException(nameof(text));
Position = 0;
Length = text.Length;
}
public StringSlice(string text, int position, int length)
{
_text = text ?? throw new ArgumentNullException(nameof(text));
Position = position;
Length = length;
}
public char this[int index] => _text[Position + index];
public bool Equals(StringSlice other)
{
if (Length != other.Length) return false;
for (int i = 0; i < Length; i++)
{
if (this[i] != other[i])
{
return false;
}
}
return true;
}
public override bool Equals(object obj)
{
return obj is StringSlice other && Equals(other);
}
public override int GetHashCode()
{
unchecked
{
var hashCode = Length;
for (int i = 0; i < Length; i++)
{
hashCode = (hashCode * 397) ^ this[i];
}
return hashCode;
}
}
public static bool operator ==(StringSlice left, StringSlice right)
{
return left.Equals(right);
}
public static bool operator !=(StringSlice left, StringSlice right)
{
return !left.Equals(right);
}
public override string ToString()
{
return _text.Substring(Position, Length);
}
public bool StartsWith(string text)
{
if (text == null) throw new ArgumentNullException(nameof(text));
if (Length < text.Length) return false;
for (var i = 0; i < text.Length; i++)
{
var c = text[i];
if (_text[Position + i] != c) return false;
}
return true;
}
public bool Contains(char c) => _text.Skip(Position).Take(Length).Any(elm => elm == c);
public int IndexOf(char c)
{
for (var i = 0; i < Length; i++)
{
if (_text[Position + i] == c)
{
return i;
}
}
return -1;
}
}
}
#endif