#define DEBUG_TYPE "mcexpr"
#include "llvm/MC/MCExpr.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/MC/MCAsmLayout.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCValue.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
namespace {
namespace stats {
STATISTIC(MCExprEvaluate, "Number of MCExpr evaluations");
}
}
static bool printMipsSymbolRef(const MCSymbolRefExpr &SRE,
const MCSymbol &Sym, raw_ostream &OS) {
MCSymbolRefExpr::VariantKind Kind= SRE.getKind();
switch (Kind) {
default:
return false;
case MCSymbolRefExpr::VK_Mips_None: break;
case MCSymbolRefExpr::VK_Mips_GPREL: OS << "%gp_rel("; break;
case MCSymbolRefExpr::VK_Mips_GOT_CALL: OS << "%call16("; break;
case MCSymbolRefExpr::VK_Mips_GOT: OS << "%got("; break;
case MCSymbolRefExpr::VK_Mips_ABS_HI: OS << "%hi("; break;
case MCSymbolRefExpr::VK_Mips_ABS_LO: OS << "%lo("; break;
case MCSymbolRefExpr::VK_Mips_TLSGD: OS << "%tlsgd("; break;
case MCSymbolRefExpr::VK_Mips_GOTTPREL: OS << "%gottprel("; break;
case MCSymbolRefExpr::VK_Mips_TPREL_HI: OS << "%tprel_hi("; break;
case MCSymbolRefExpr::VK_Mips_TPREL_LO: OS << "%tprel_lo("; break;
case MCSymbolRefExpr::VK_Mips_GPOFF_HI: OS << "%hi(%neg(%gp_rel("; break;
case MCSymbolRefExpr::VK_Mips_GPOFF_LO: OS << "%lo(%neg(%gp_rel("; break;
case MCSymbolRefExpr::VK_Mips_GOT_DISP: OS << "%got_disp("; break;
case MCSymbolRefExpr::VK_Mips_GOT_PAGE: OS << "%got_page("; break;
case MCSymbolRefExpr::VK_Mips_GOT_OFST: OS << "%got_ofst("; break;
}
OS << Sym;
if (Kind != MCSymbolRefExpr::VK_Mips_None)
OS << ')';
return true;
}
void MCExpr::print(raw_ostream &OS) const {
switch (getKind()) {
case MCExpr::Target:
return cast<MCTargetExpr>(this)->PrintImpl(OS);
case MCExpr::Constant:
OS << cast<MCConstantExpr>(*this).getValue();
return;
case MCExpr::SymbolRef: {
const MCSymbolRefExpr &SRE = cast<MCSymbolRefExpr>(*this);
const MCSymbol &Sym = SRE.getSymbol();
bool UseParens = Sym.getName()[0] == '$';
if (printMipsSymbolRef(SRE, Sym, OS))
return;
if (SRE.getKind() == MCSymbolRefExpr::VK_PPC_DARWIN_HA16 ||
SRE.getKind() == MCSymbolRefExpr::VK_PPC_DARWIN_LO16) {
OS << MCSymbolRefExpr::getVariantKindName(SRE.getKind());
UseParens = true;
}
if (UseParens)
OS << '(' << Sym << ')';
else
OS << Sym;
if (SRE.getKind() == MCSymbolRefExpr::VK_ARM_PLT ||
SRE.getKind() == MCSymbolRefExpr::VK_ARM_TLSGD ||
SRE.getKind() == MCSymbolRefExpr::VK_ARM_GOT ||
SRE.getKind() == MCSymbolRefExpr::VK_ARM_GOTOFF ||
SRE.getKind() == MCSymbolRefExpr::VK_ARM_TPOFF ||
SRE.getKind() == MCSymbolRefExpr::VK_ARM_GOTTPOFF)
OS << MCSymbolRefExpr::getVariantKindName(SRE.getKind());
else if (SRE.getKind() != MCSymbolRefExpr::VK_None &&
SRE.getKind() != MCSymbolRefExpr::VK_PPC_DARWIN_HA16 &&
SRE.getKind() != MCSymbolRefExpr::VK_PPC_DARWIN_LO16)
OS << '@' << MCSymbolRefExpr::getVariantKindName(SRE.getKind());
return;
}
case MCExpr::Unary: {
const MCUnaryExpr &UE = cast<MCUnaryExpr>(*this);
switch (UE.getOpcode()) {
default: assert(0 && "Invalid opcode!");
case MCUnaryExpr::LNot: OS << '!'; break;
case MCUnaryExpr::Minus: OS << '-'; break;
case MCUnaryExpr::Not: OS << '~'; break;
case MCUnaryExpr::Plus: OS << '+'; break;
}
OS << *UE.getSubExpr();
return;
}
case MCExpr::Binary: {
const MCBinaryExpr &BE = cast<MCBinaryExpr>(*this);
if (isa<MCConstantExpr>(BE.getLHS()) || isa<MCSymbolRefExpr>(BE.getLHS())) {
OS << *BE.getLHS();
} else {
OS << '(' << *BE.getLHS() << ')';
}
switch (BE.getOpcode()) {
default: assert(0 && "Invalid opcode!");
case MCBinaryExpr::Add:
if (const MCConstantExpr *RHSC = dyn_cast<MCConstantExpr>(BE.getRHS())) {
if (RHSC->getValue() < 0) {
OS << RHSC->getValue();
return;
}
}
OS << '+';
break;
case MCBinaryExpr::And: OS << '&'; break;
case MCBinaryExpr::Div: OS << '/'; break;
case MCBinaryExpr::EQ: OS << "=="; break;
case MCBinaryExpr::GT: OS << '>'; break;
case MCBinaryExpr::GTE: OS << ">="; break;
case MCBinaryExpr::LAnd: OS << "&&"; break;
case MCBinaryExpr::LOr: OS << "||"; break;
case MCBinaryExpr::LT: OS << '<'; break;
case MCBinaryExpr::LTE: OS << "<="; break;
case MCBinaryExpr::Mod: OS << '%'; break;
case MCBinaryExpr::Mul: OS << '*'; break;
case MCBinaryExpr::NE: OS << "!="; break;
case MCBinaryExpr::Or: OS << '|'; break;
case MCBinaryExpr::Shl: OS << "<<"; break;
case MCBinaryExpr::Shr: OS << ">>"; break;
case MCBinaryExpr::Sub: OS << '-'; break;
case MCBinaryExpr::Xor: OS << '^'; break;
}
if (isa<MCConstantExpr>(BE.getRHS()) || isa<MCSymbolRefExpr>(BE.getRHS())) {
OS << *BE.getRHS();
} else {
OS << '(' << *BE.getRHS() << ')';
}
return;
}
}
assert(0 && "Invalid expression kind!");
}
void MCExpr::dump() const {
print(dbgs());
dbgs() << '\n';
}
const MCBinaryExpr *MCBinaryExpr::Create(Opcode Opc, const MCExpr *LHS,
const MCExpr *RHS, MCContext &Ctx) {
return new (Ctx) MCBinaryExpr(Opc, LHS, RHS);
}
const MCUnaryExpr *MCUnaryExpr::Create(Opcode Opc, const MCExpr *Expr,
MCContext &Ctx) {
return new (Ctx) MCUnaryExpr(Opc, Expr);
}
const MCConstantExpr *MCConstantExpr::Create(int64_t Value, MCContext &Ctx) {
return new (Ctx) MCConstantExpr(Value);
}
const MCSymbolRefExpr *MCSymbolRefExpr::Create(const MCSymbol *Sym,
VariantKind Kind,
MCContext &Ctx) {
return new (Ctx) MCSymbolRefExpr(Sym, Kind);
}
const MCSymbolRefExpr *MCSymbolRefExpr::Create(StringRef Name, VariantKind Kind,
MCContext &Ctx) {
return Create(Ctx.GetOrCreateSymbol(Name), Kind, Ctx);
}
StringRef MCSymbolRefExpr::getVariantKindName(VariantKind Kind) {
switch (Kind) {
default:
case VK_Invalid: return "<<invalid>>";
case VK_None: return "<<none>>";
case VK_GOT: return "GOT";
case VK_GOTOFF: return "GOTOFF";
case VK_GOTPCREL: return "GOTPCREL";
case VK_GOTTPOFF: return "GOTTPOFF";
case VK_INDNTPOFF: return "INDNTPOFF";
case VK_NTPOFF: return "NTPOFF";
case VK_GOTNTPOFF: return "GOTNTPOFF";
case VK_PLT: return "PLT";
case VK_TLSGD: return "TLSGD";
case VK_TLSLD: return "TLSLD";
case VK_TLSLDM: return "TLSLDM";
case VK_TPOFF: return "TPOFF";
case VK_DTPOFF: return "DTPOFF";
case VK_TLVP: return "TLVP";
case VK_ARM_PLT: return "(PLT)";
case VK_ARM_GOT: return "(GOT)";
case VK_ARM_GOTOFF: return "(GOTOFF)";
case VK_ARM_TPOFF: return "(tpoff)";
case VK_ARM_GOTTPOFF: return "(gottpoff)";
case VK_ARM_TLSGD: return "(tlsgd)";
case VK_PPC_TOC: return "toc";
case VK_PPC_DARWIN_HA16: return "ha16";
case VK_PPC_DARWIN_LO16: return "lo16";
case VK_PPC_GAS_HA16: return "ha";
case VK_PPC_GAS_LO16: return "l";
}
}
MCSymbolRefExpr::VariantKind
MCSymbolRefExpr::getVariantKindForName(StringRef Name) {
return StringSwitch<VariantKind>(Name)
.Case("GOT", VK_GOT)
.Case("got", VK_GOT)
.Case("GOTOFF", VK_GOTOFF)
.Case("gotoff", VK_GOTOFF)
.Case("GOTPCREL", VK_GOTPCREL)
.Case("gotpcrel", VK_GOTPCREL)
.Case("GOTTPOFF", VK_GOTTPOFF)
.Case("gottpoff", VK_GOTTPOFF)
.Case("INDNTPOFF", VK_INDNTPOFF)
.Case("indntpoff", VK_INDNTPOFF)
.Case("NTPOFF", VK_NTPOFF)
.Case("ntpoff", VK_NTPOFF)
.Case("GOTNTPOFF", VK_GOTNTPOFF)
.Case("gotntpoff", VK_GOTNTPOFF)
.Case("PLT", VK_PLT)
.Case("plt", VK_PLT)
.Case("TLSGD", VK_TLSGD)
.Case("tlsgd", VK_TLSGD)
.Case("TLSLD", VK_TLSLD)
.Case("tlsld", VK_TLSLD)
.Case("TLSLDM", VK_TLSLDM)
.Case("tlsldm", VK_TLSLDM)
.Case("TPOFF", VK_TPOFF)
.Case("tpoff", VK_TPOFF)
.Case("DTPOFF", VK_DTPOFF)
.Case("dtpoff", VK_DTPOFF)
.Case("TLVP", VK_TLVP)
.Case("tlvp", VK_TLVP)
.Default(VK_Invalid);
}
void MCTargetExpr::Anchor() {}
bool MCExpr::EvaluateAsAbsolute(int64_t &Res) const {
return EvaluateAsAbsolute(Res, 0, 0, 0);
}
bool MCExpr::EvaluateAsAbsolute(int64_t &Res,
const MCAsmLayout &Layout) const {
return EvaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, 0);
}
bool MCExpr::EvaluateAsAbsolute(int64_t &Res,
const MCAsmLayout &Layout,
const SectionAddrMap &Addrs) const {
return EvaluateAsAbsolute(Res, &Layout.getAssembler(), &Layout, &Addrs);
}
bool MCExpr::EvaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const {
return EvaluateAsAbsolute(Res, &Asm, 0, 0);
}
bool MCExpr::EvaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm,
const MCAsmLayout *Layout,
const SectionAddrMap *Addrs) const {
MCValue Value;
if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(this)) {
Res = CE->getValue();
return true;
}
bool IsRelocatable =
EvaluateAsRelocatableImpl(Value, Asm, Layout, Addrs, Addrs);
Res = Value.getConstant();
return IsRelocatable && Value.isAbsolute();
}
static void AttemptToFoldSymbolOffsetDifference(const MCAssembler *Asm,
const MCAsmLayout *Layout,
const SectionAddrMap *Addrs,
bool InSet,
const MCSymbolRefExpr *&A,
const MCSymbolRefExpr *&B,
int64_t &Addend) {
if (!A || !B)
return;
const MCSymbol &SA = A->getSymbol();
const MCSymbol &SB = B->getSymbol();
if (SA.isUndefined() || SB.isUndefined())
return;
if (!Asm->getWriter().IsSymbolRefDifferenceFullyResolved(*Asm, A, B, InSet))
return;
MCSymbolData &AD = Asm->getSymbolData(SA);
MCSymbolData &BD = Asm->getSymbolData(SB);
if (AD.getFragment() == BD.getFragment()) {
Addend += (AD.getOffset() - BD.getOffset());
if (Asm->isThumbFunc(&SA))
Addend |= 1;
A = B = 0;
return;
}
if (!Layout)
return;
const MCSectionData &SecA = *AD.getFragment()->getParent();
const MCSectionData &SecB = *BD.getFragment()->getParent();
if ((&SecA != &SecB) && !Addrs)
return;
Addend += (Layout->getSymbolOffset(&Asm->getSymbolData(A->getSymbol())) -
Layout->getSymbolOffset(&Asm->getSymbolData(B->getSymbol())));
if (Addrs && (&SecA != &SecB))
Addend += (Addrs->lookup(&SecA) - Addrs->lookup(&SecB));
A = B = 0;
}
static bool EvaluateSymbolicAdd(const MCAssembler *Asm,
const MCAsmLayout *Layout,
const SectionAddrMap *Addrs,
bool InSet,
const MCValue &LHS,const MCSymbolRefExpr *RHS_A,
const MCSymbolRefExpr *RHS_B, int64_t RHS_Cst,
MCValue &Res) {
const MCSymbolRefExpr *LHS_A = LHS.getSymA();
const MCSymbolRefExpr *LHS_B = LHS.getSymB();
int64_t LHS_Cst = LHS.getConstant();
int64_t Result_Cst = LHS_Cst + RHS_Cst;
assert((!Layout || Asm) &&
"Must have an assembler object if layout is given!");
if (Asm) {
AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, LHS_A, LHS_B,
Result_Cst);
AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, LHS_A, RHS_B,
Result_Cst);
AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, RHS_A, LHS_B,
Result_Cst);
AttemptToFoldSymbolOffsetDifference(Asm, Layout, Addrs, InSet, RHS_A, RHS_B,
Result_Cst);
}
if ((LHS_A && RHS_A) || (LHS_B && RHS_B))
return false;
const MCSymbolRefExpr *A = LHS_A ? LHS_A : RHS_A;
const MCSymbolRefExpr *B = LHS_B ? LHS_B : RHS_B;
if (B && !A)
return false;
Res = MCValue::get(A, B, Result_Cst);
return true;
}
bool MCExpr::EvaluateAsRelocatable(MCValue &Res,
const MCAsmLayout &Layout) const {
return EvaluateAsRelocatableImpl(Res, &Layout.getAssembler(), &Layout,
0, false);
}
bool MCExpr::EvaluateAsRelocatableImpl(MCValue &Res,
const MCAssembler *Asm,
const MCAsmLayout *Layout,
const SectionAddrMap *Addrs,
bool InSet) const {
++stats::MCExprEvaluate;
switch (getKind()) {
case Target:
return cast<MCTargetExpr>(this)->EvaluateAsRelocatableImpl(Res, Layout);
case Constant:
Res = MCValue::get(cast<MCConstantExpr>(this)->getValue());
return true;
case SymbolRef: {
const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this);
const MCSymbol &Sym = SRE->getSymbol();
if (Sym.isVariable() && SRE->getKind() == MCSymbolRefExpr::VK_None) {
bool Ret = Sym.getVariableValue()->EvaluateAsRelocatableImpl(Res, Asm,
Layout,
Addrs,
true);
if (Ret && !Res.getSymA() && !Res.getSymB())
return true;
}
Res = MCValue::get(SRE, 0, 0);
return true;
}
case Unary: {
const MCUnaryExpr *AUE = cast<MCUnaryExpr>(this);
MCValue Value;
if (!AUE->getSubExpr()->EvaluateAsRelocatableImpl(Value, Asm, Layout,
Addrs, InSet))
return false;
switch (AUE->getOpcode()) {
case MCUnaryExpr::LNot:
if (!Value.isAbsolute())
return false;
Res = MCValue::get(!Value.getConstant());
break;
case MCUnaryExpr::Minus:
if (Value.getSymA() && !Value.getSymB())
return false;
Res = MCValue::get(Value.getSymB(), Value.getSymA(),
-Value.getConstant());
break;
case MCUnaryExpr::Not:
if (!Value.isAbsolute())
return false;
Res = MCValue::get(~Value.getConstant());
break;
case MCUnaryExpr::Plus:
Res = Value;
break;
}
return true;
}
case Binary: {
const MCBinaryExpr *ABE = cast<MCBinaryExpr>(this);
MCValue LHSValue, RHSValue;
if (!ABE->getLHS()->EvaluateAsRelocatableImpl(LHSValue, Asm, Layout,
Addrs, InSet) ||
!ABE->getRHS()->EvaluateAsRelocatableImpl(RHSValue, Asm, Layout,
Addrs, InSet))
return false;
if (!LHSValue.isAbsolute() || !RHSValue.isAbsolute()) {
switch (ABE->getOpcode()) {
default:
return false;
case MCBinaryExpr::Sub:
return EvaluateSymbolicAdd(Asm, Layout, Addrs, InSet, LHSValue,
RHSValue.getSymB(), RHSValue.getSymA(),
-RHSValue.getConstant(),
Res);
case MCBinaryExpr::Add:
return EvaluateSymbolicAdd(Asm, Layout, Addrs, InSet, LHSValue,
RHSValue.getSymA(), RHSValue.getSymB(),
RHSValue.getConstant(),
Res);
}
}
int64_t LHS = LHSValue.getConstant(), RHS = RHSValue.getConstant();
int64_t Result = 0;
switch (ABE->getOpcode()) {
case MCBinaryExpr::Add: Result = LHS + RHS; break;
case MCBinaryExpr::And: Result = LHS & RHS; break;
case MCBinaryExpr::Div: Result = LHS / RHS; break;
case MCBinaryExpr::EQ: Result = LHS == RHS; break;
case MCBinaryExpr::GT: Result = LHS > RHS; break;
case MCBinaryExpr::GTE: Result = LHS >= RHS; break;
case MCBinaryExpr::LAnd: Result = LHS && RHS; break;
case MCBinaryExpr::LOr: Result = LHS || RHS; break;
case MCBinaryExpr::LT: Result = LHS < RHS; break;
case MCBinaryExpr::LTE: Result = LHS <= RHS; break;
case MCBinaryExpr::Mod: Result = LHS % RHS; break;
case MCBinaryExpr::Mul: Result = LHS * RHS; break;
case MCBinaryExpr::NE: Result = LHS != RHS; break;
case MCBinaryExpr::Or: Result = LHS | RHS; break;
case MCBinaryExpr::Shl: Result = LHS << RHS; break;
case MCBinaryExpr::Shr: Result = LHS >> RHS; break;
case MCBinaryExpr::Sub: Result = LHS - RHS; break;
case MCBinaryExpr::Xor: Result = LHS ^ RHS; break;
}
Res = MCValue::get(Result);
return true;
}
}
assert(0 && "Invalid assembly expression kind!");
return false;
}
const MCSection *MCExpr::FindAssociatedSection() const {
switch (getKind()) {
case Target:
return cast<MCTargetExpr>(this)->FindAssociatedSection();
case Constant:
return MCSymbol::AbsolutePseudoSection;
case SymbolRef: {
const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(this);
const MCSymbol &Sym = SRE->getSymbol();
if (Sym.isDefined())
return &Sym.getSection();
return 0;
}
case Unary:
return cast<MCUnaryExpr>(this)->getSubExpr()->FindAssociatedSection();
case Binary: {
const MCBinaryExpr *BE = cast<MCBinaryExpr>(this);
const MCSection *LHS_S = BE->getLHS()->FindAssociatedSection();
const MCSection *RHS_S = BE->getRHS()->FindAssociatedSection();
if (LHS_S == MCSymbol::AbsolutePseudoSection)
return RHS_S;
if (RHS_S == MCSymbol::AbsolutePseudoSection)
return LHS_S;
return LHS_S ? LHS_S : RHS_S;
}
}
assert(0 && "Invalid assembly expression kind!");
return 0;
}