MCExpr.cpp File Reference

#include "llvm/MC/MCExpr.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Config/llvm-config.h"
#include "llvm/MC/MCAsmBackend.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCObjectWriter.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCValue.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <cstdint>

Go to the source code of this file.

Namespaces
namespace	stats

Macros
#define	DEBUG_TYPE   "mcexpr"

Functions
static void	AttemptToFoldSymbolOffsetDifference (const MCAssembler *Asm, const SectionAddrMap *Addrs, bool InSet, const MCSymbolRefExpr *&A, const MCSymbolRefExpr *&B, int64_t &Addend)
	Helper method for.
static bool	evaluateSymbolicAdd (const MCAssembler *Asm, const SectionAddrMap *Addrs, bool InSet, const MCValue &LHS, const MCValue &RHS, MCValue &Res)
	Evaluate the result of an add between (conceptually) two MCValues.
static bool	canExpand (const MCSymbol &Sym, bool InSet)

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "mcexpr"

Definition at line 30 of file MCExpr.cpp.

Function Documentation

AttemptToFoldSymbolOffsetDifference()

static void AttemptToFoldSymbolOffsetDifference ( const MCAssembler *  Asm, const SectionAddrMap *  Addrs, bool  InSet, const MCSymbolRefExpr *&  A, const MCSymbolRefExpr *&  B, int64_t &  Addend  )

static

Helper method for.

See also

EvaluateSymbolAdd().

Definition at line 589 of file MCExpr.cpp.

References A, B, DF, llvm::MCSymbol::getFragment(), llvm::MCFragment::getLayoutOrder(), llvm::MCFragment::getNext(), llvm::MCSymbol::getOffset(), llvm::MCFragment::getParent(), llvm::MCSection::hasInstructions(), llvm::MCSymbol::isUndefined(), llvm::MCSymbol::isVariable(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::lookup(), llvm::Reverse, and std::swap().

Referenced by evaluateSymbolicAdd().

canExpand()

static bool canExpand ( const MCSymbol &  Sym, bool  InSet  )

static

Definition at line 797 of file MCExpr.cpp.

References Sym, and llvm::MCSymbolRefExpr::VK_WEAKREF.

Referenced by llvm::MCExpr::evaluateAsRelocatableImpl().

evaluateSymbolicAdd()

static bool evaluateSymbolicAdd ( const MCAssembler *  Asm, const SectionAddrMap *  Addrs, bool  InSet, const MCValue &  LHS, const MCValue &  RHS, MCValue &  Res  )

static

Evaluate the result of an add between (conceptually) two MCValues.

This routine conceptually attempts to construct an MCValue: Result = (Result_A - Result_B + Result_Cst) from two MCValue's LHS and RHS where Result = LHS + RHS and Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst).

This routine attempts to aggressively fold the operands such that the result is representable in an MCValue, but may not always succeed.

Returns

True on success, false if the result is not representable in an MCValue. NOTE: It is really important to have both the Asm and Layout arguments. They might look redundant, but this function can be used before layout is done (see the object streamer for example) and having the Asm argument lets us avoid relaxations early.

Definition at line 733 of file MCExpr.cpp.

References A, AttemptToFoldSymbolOffsetDifference(), B, llvm::MCValue::get(), LHS, and RHS.

Referenced by llvm::MCExpr::evaluateAsRelocatableImpl().