6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-01 15:11:24 +00:00
Code Issues Projects Releases Wiki Activity

MC: Improve expression parsing and implement evaluation of absolute expressions

Browse Source 
(missed files).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74450 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Daniel Dunbar 2009-06-29 20:40:36 +00:00
parent 70f4426750
commit fc6877aec9
2 changed files with 249 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

92
tools/llvm-mc/AsmExpr.cpp Normal file
View File

@ -0,0 +1,92 @@
//===- AsmExpr.cpp - Assembly file expressions ----------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "AsmExpr.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCValue.h"
using namespace llvm;
AsmExpr::~AsmExpr() {
}
bool AsmExpr::EvaluateAsAbsolute(MCContext &Ctx, int64_t &Res) const {
switch (getKind()) {
default:
assert(0 && "Invalid assembly expression kind!");
case Constant:
Res = cast<AsmConstantExpr>(this)->getValue();
return true;
case SymbolRef: {
MCSymbol *Sym = cast<AsmSymbolRefExpr>(this)->getSymbol();
const MCValue *Value = Ctx.GetSymbolValue(Sym);
// FIXME: Return more information about the failure.
if (!Value || !Value->isConstant())
return false;
Res = Value->getConstant();
return true;
}
case Unary: {
const AsmUnaryExpr *AUE = cast<AsmUnaryExpr>(this);
int64_t Value;
if (!AUE->getSubExpr()->EvaluateAsAbsolute(Ctx, Value))
return false;
switch (AUE->getOpcode()) {
case AsmUnaryExpr::LNot: Res = !Value; break;
case AsmUnaryExpr::Minus: Res = -Value; break;
case AsmUnaryExpr::Not: Res = ~Value; break;
case AsmUnaryExpr::Plus: Res = +Value; break;
}
return true;
}
case Binary: {
const AsmBinaryExpr *ABE = cast<AsmBinaryExpr>(this);
int64_t LHS, RHS;
if (!ABE->getLHS()->EvaluateAsAbsolute(Ctx, LHS) ||
!ABE->getRHS()->EvaluateAsAbsolute(Ctx, RHS))
return false;
// FIXME: We need target hooks for the evaluation. It may be limited in
// width, and gas defines the result of comparisons differently from Apple
// as (the result is sign extended).
switch (ABE->getOpcode()) {
case AsmBinaryExpr::Add: Res = LHS + RHS; break;
case AsmBinaryExpr::And: Res = LHS & RHS; break;
case AsmBinaryExpr::Div: Res = LHS / RHS; break;
case AsmBinaryExpr::EQ: Res = LHS == RHS; break;
case AsmBinaryExpr::GT: Res = LHS > RHS; break;
case AsmBinaryExpr::GTE: Res = LHS >= RHS; break;
case AsmBinaryExpr::LAnd: Res = LHS && RHS; break;
case AsmBinaryExpr::LOr: Res = LHS || RHS; break;
case AsmBinaryExpr::LT: Res = LHS < RHS; break;
case AsmBinaryExpr::LTE: Res = LHS <= RHS; break;
case AsmBinaryExpr::Mod: Res = LHS % RHS; break;
case AsmBinaryExpr::Mul: Res = LHS * RHS; break;
case AsmBinaryExpr::NE: Res = LHS != RHS; break;
case AsmBinaryExpr::Or: Res = LHS | RHS; break;
case AsmBinaryExpr::Shl: Res = LHS << RHS; break;
case AsmBinaryExpr::Shr: Res = LHS >> RHS; break;
case AsmBinaryExpr::Sub: Res = LHS - RHS; break;
case AsmBinaryExpr::Xor: Res = LHS ^ RHS; break;
}
return true;
}
}
}

157
tools/llvm-mc/AsmExpr.h Normal file
View File

@ -0,0 +1,157 @@
//===- AsmExpr.h - Assembly file expressions --------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef ASMEXPR_H
#define ASMEXPR_H
#include "llvm/Support/Casting.h"
#include "llvm/Support/DataTypes.h"
namespace llvm {
class MCContext;
class MCSymbol;
class AsmExpr {
public:
enum AsmExprKind {
Binary, /// Binary expressions.
Constant, /// Constant expressions.
SymbolRef, /// References to labels and assigned expressions.
Unary /// Unary expressions.
};
private:
AsmExprKind Kind;
protected:
AsmExpr(AsmExprKind _Kind) : Kind(_Kind) {}
public:
virtual ~AsmExpr();
AsmExprKind getKind() const { return Kind; }
/// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value.
///
/// @param Res - The absolute value if evaluation succeeds.
/// @result - True on success.
bool EvaluateAsAbsolute(MCContext &Ctx, int64_t &Res) const;
static bool classof(const AsmExpr *) { return true; }
};
class AsmConstantExpr : public AsmExpr {
int64_t Value;
public:
AsmConstantExpr(int64_t _Value)
: AsmExpr(AsmExpr::Constant), Value(_Value) {}
int64_t getValue() const { return Value; }
static bool classof(const AsmExpr *E) {
return E->getKind() == AsmExpr::Constant;
}
static bool classof(const AsmConstantExpr *) { return true; }
};
class AsmSymbolRefExpr : public AsmExpr {
MCSymbol *Symbol;
public:
AsmSymbolRefExpr(MCSymbol *_Symbol)
: AsmExpr(AsmExpr::SymbolRef), Symbol(_Symbol) {}
MCSymbol *getSymbol() const { return Symbol; }
static bool classof(const AsmExpr *E) {
return E->getKind() == AsmExpr::SymbolRef;
}
static bool classof(const AsmSymbolRefExpr *) { return true; }
};
class AsmUnaryExpr : public AsmExpr {
public:
enum Opcode {
LNot, /// Logical negation.
Minus, /// Unary minus.
Not, /// Bit-wise negation.
Plus /// Unary plus.
};
private:
Opcode Op;
AsmExpr *Expr;
public:
AsmUnaryExpr(Opcode _Op, AsmExpr *_Expr)
: AsmExpr(AsmExpr::Unary), Op(_Op), Expr(_Expr) {}
~AsmUnaryExpr() {
delete Expr;
}
Opcode getOpcode() const { return Op; }
AsmExpr *getSubExpr() const { return Expr; }
static bool classof(const AsmExpr *E) {
return E->getKind() == AsmExpr::Unary;
}
static bool classof(const AsmUnaryExpr *) { return true; }
};
class AsmBinaryExpr : public AsmExpr {
public:
enum Opcode {
Add, /// Addition.
And, /// Bitwise and.
Div, /// Division.
EQ, /// Equality comparison.
GT, /// Greater than comparison.
GTE, /// Greater than or equal comparison.
LAnd, /// Logical and.
LOr, /// Logical or.
LT, /// Less than comparison.
LTE, /// Less than or equal comparison.
Mod, /// Modulus.
Mul, /// Multiplication.
NE, /// Inequality comparison.
Or, /// Bitwise or.
Shl, /// Bitwise shift left.
Shr, /// Bitwise shift right.
Sub, /// Subtraction.
Xor /// Bitwise exclusive or.
};
private:
Opcode Op;
AsmExpr *LHS, *RHS;
public:
AsmBinaryExpr(Opcode _Op, AsmExpr *_LHS, AsmExpr *_RHS)
: AsmExpr(AsmExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
~AsmBinaryExpr() {
delete LHS;
delete RHS;
}
Opcode getOpcode() const { return Op; }
AsmExpr *getLHS() const { return LHS; }
AsmExpr *getRHS() const { return RHS; }
static bool classof(const AsmExpr *E) {
return E->getKind() == AsmExpr::Binary;
}
static bool classof(const AsmBinaryExpr *) { return true; }
};
} // end namespace llvm
#endif