| //===- MCExpr.cpp - Assembly Level Expression Implementation --------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #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/MCObjectWriter.h" |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/MC/MCValue.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/raw_ostream.h" |
| using namespace llvm; |
| |
| namespace { |
| namespace stats { |
| STATISTIC(MCExprEvaluate, "Number of MCExpr evaluations"); |
| } |
| } |
| |
| 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(); |
| // Parenthesize names that start with $ so that they don't look like |
| // absolute names. |
| bool UseParens = Sym.getName()[0] == '$'; |
| if (UseParens) |
| OS << '(' << Sym << ')'; |
| else |
| OS << Sym; |
| |
| if (SRE.getKind() == MCSymbolRefExpr::VK_ARM_NONE || |
| 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 || |
| SRE.getKind() == MCSymbolRefExpr::VK_ARM_TARGET1 || |
| SRE.getKind() == MCSymbolRefExpr::VK_ARM_TARGET2 || |
| SRE.getKind() == MCSymbolRefExpr::VK_ARM_PREL31) |
| OS << MCSymbolRefExpr::getVariantKindName(SRE.getKind()); |
| else if (SRE.getKind() != MCSymbolRefExpr::VK_None) |
| OS << '@' << MCSymbolRefExpr::getVariantKindName(SRE.getKind()); |
| |
| return; |
| } |
| |
| case MCExpr::Unary: { |
| const MCUnaryExpr &UE = cast<MCUnaryExpr>(*this); |
| switch (UE.getOpcode()) { |
| 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); |
| |
| // Only print parens around the LHS if it is non-trivial. |
| if (isa<MCConstantExpr>(BE.getLHS()) || isa<MCSymbolRefExpr>(BE.getLHS())) { |
| OS << *BE.getLHS(); |
| } else { |
| OS << '(' << *BE.getLHS() << ')'; |
| } |
| |
| switch (BE.getOpcode()) { |
| case MCBinaryExpr::Add: |
| // Print "X-42" instead of "X+-42". |
| 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; |
| } |
| |
| // Only print parens around the LHS if it is non-trivial. |
| if (isa<MCConstantExpr>(BE.getRHS()) || isa<MCSymbolRefExpr>(BE.getRHS())) { |
| OS << *BE.getRHS(); |
| } else { |
| OS << '(' << *BE.getRHS() << ')'; |
| } |
| return; |
| } |
| } |
| |
| llvm_unreachable("Invalid expression kind!"); |
| } |
| |
| #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) |
| void MCExpr::dump() const { |
| print(dbgs()); |
| dbgs() << '\n'; |
| } |
| #endif |
| |
| /* *** */ |
| |
| 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) { |
| 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_SECREL: return "SECREL32"; |
| case VK_ARM_NONE: return "(NONE)"; |
| 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_ARM_TARGET1: return "(target1)"; |
| case VK_ARM_TARGET2: return "(target2)"; |
| case VK_ARM_PREL31: return "(prel31)"; |
| case VK_PPC_LO: return "l"; |
| case VK_PPC_HI: return "h"; |
| case VK_PPC_HA: return "ha"; |
| case VK_PPC_HIGHER: return "higher"; |
| case VK_PPC_HIGHERA: return "highera"; |
| case VK_PPC_HIGHEST: return "highest"; |
| case VK_PPC_HIGHESTA: return "highesta"; |
| case VK_PPC_GOT_LO: return "got@l"; |
| case VK_PPC_GOT_HI: return "got@h"; |
| case VK_PPC_GOT_HA: return "got@ha"; |
| case VK_PPC_TOCBASE: return "tocbase"; |
| case VK_PPC_TOC: return "toc"; |
| case VK_PPC_TOC_LO: return "toc@l"; |
| case VK_PPC_TOC_HI: return "toc@h"; |
| case VK_PPC_TOC_HA: return "toc@ha"; |
| case VK_PPC_DTPMOD: return "dtpmod"; |
| case VK_PPC_TPREL: return "tprel"; |
| case VK_PPC_TPREL_LO: return "tprel@l"; |
| case VK_PPC_TPREL_HI: return "tprel@h"; |
| case VK_PPC_TPREL_HA: return "tprel@ha"; |
| case VK_PPC_TPREL_HIGHER: return "tprel@higher"; |
| case VK_PPC_TPREL_HIGHERA: return "tprel@highera"; |
| case VK_PPC_TPREL_HIGHEST: return "tprel@highest"; |
| case VK_PPC_TPREL_HIGHESTA: return "tprel@highesta"; |
| case VK_PPC_DTPREL: return "dtprel"; |
| case VK_PPC_DTPREL_LO: return "dtprel@l"; |
| case VK_PPC_DTPREL_HI: return "dtprel@h"; |
| case VK_PPC_DTPREL_HA: return "dtprel@ha"; |
| case VK_PPC_DTPREL_HIGHER: return "dtprel@higher"; |
| case VK_PPC_DTPREL_HIGHERA: return "dtprel@highera"; |
| case VK_PPC_DTPREL_HIGHEST: return "dtprel@highest"; |
| case VK_PPC_DTPREL_HIGHESTA: return "dtprel@highesta"; |
| case VK_PPC_GOT_TPREL: return "got@tprel"; |
| case VK_PPC_GOT_TPREL_LO: return "got@tprel@l"; |
| case VK_PPC_GOT_TPREL_HI: return "got@tprel@h"; |
| case VK_PPC_GOT_TPREL_HA: return "got@tprel@ha"; |
| case VK_PPC_GOT_DTPREL: return "got@dtprel"; |
| case VK_PPC_GOT_DTPREL_LO: return "got@dtprel@l"; |
| case VK_PPC_GOT_DTPREL_HI: return "got@dtprel@h"; |
| case VK_PPC_GOT_DTPREL_HA: return "got@dtprel@ha"; |
| case VK_PPC_TLS: return "tls"; |
| case VK_PPC_GOT_TLSGD: return "got@tlsgd"; |
| case VK_PPC_GOT_TLSGD_LO: return "got@tlsgd@l"; |
| case VK_PPC_GOT_TLSGD_HI: return "got@tlsgd@h"; |
| case VK_PPC_GOT_TLSGD_HA: return "got@tlsgd@ha"; |
| case VK_PPC_TLSGD: return "tlsgd"; |
| case VK_PPC_GOT_TLSLD: return "got@tlsld"; |
| case VK_PPC_GOT_TLSLD_LO: return "got@tlsld@l"; |
| case VK_PPC_GOT_TLSLD_HI: return "got@tlsld@h"; |
| case VK_PPC_GOT_TLSLD_HA: return "got@tlsld@ha"; |
| case VK_PPC_TLSLD: return "tlsld"; |
| case VK_Mips_GPREL: return "GPREL"; |
| case VK_Mips_GOT_CALL: return "GOT_CALL"; |
| case VK_Mips_GOT16: return "GOT16"; |
| case VK_Mips_GOT: return "GOT"; |
| case VK_Mips_ABS_HI: return "ABS_HI"; |
| case VK_Mips_ABS_LO: return "ABS_LO"; |
| case VK_Mips_TLSGD: return "TLSGD"; |
| case VK_Mips_TLSLDM: return "TLSLDM"; |
| case VK_Mips_DTPREL_HI: return "DTPREL_HI"; |
| case VK_Mips_DTPREL_LO: return "DTPREL_LO"; |
| case VK_Mips_GOTTPREL: return "GOTTPREL"; |
| case VK_Mips_TPREL_HI: return "TPREL_HI"; |
| case VK_Mips_TPREL_LO: return "TPREL_LO"; |
| case VK_Mips_GPOFF_HI: return "GPOFF_HI"; |
| case VK_Mips_GPOFF_LO: return "GPOFF_LO"; |
| case VK_Mips_GOT_DISP: return "GOT_DISP"; |
| case VK_Mips_GOT_PAGE: return "GOT_PAGE"; |
| case VK_Mips_GOT_OFST: return "GOT_OFST"; |
| case VK_Mips_HIGHER: return "HIGHER"; |
| case VK_Mips_HIGHEST: return "HIGHEST"; |
| case VK_Mips_GOT_HI16: return "GOT_HI16"; |
| case VK_Mips_GOT_LO16: return "GOT_LO16"; |
| case VK_Mips_CALL_HI16: return "CALL_HI16"; |
| case VK_Mips_CALL_LO16: return "CALL_LO16"; |
| case VK_COFF_IMGREL32: return "IMGREL32"; |
| } |
| llvm_unreachable("Invalid variant kind"); |
| } |
| |
| 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) |
| .Case("IMGREL", VK_COFF_IMGREL32) |
| .Case("imgrel", VK_COFF_IMGREL32) |
| .Case("SECREL32", VK_SECREL) |
| .Case("secrel32", VK_SECREL) |
| .Case("L", VK_PPC_LO) |
| .Case("l", VK_PPC_LO) |
| .Case("H", VK_PPC_HI) |
| .Case("h", VK_PPC_HI) |
| .Case("HA", VK_PPC_HA) |
| .Case("ha", VK_PPC_HA) |
| .Case("HIGHER", VK_PPC_HIGHER) |
| .Case("higher", VK_PPC_HIGHER) |
| .Case("HIGHERA", VK_PPC_HIGHERA) |
| .Case("highera", VK_PPC_HIGHERA) |
| .Case("HIGHEST", VK_PPC_HIGHEST) |
| .Case("highest", VK_PPC_HIGHEST) |
| .Case("HIGHESTA", VK_PPC_HIGHESTA) |
| .Case("highesta", VK_PPC_HIGHESTA) |
| .Case("GOT@L", VK_PPC_GOT_LO) |
| .Case("got@l", VK_PPC_GOT_LO) |
| .Case("GOT@H", VK_PPC_GOT_HI) |
| .Case("got@h", VK_PPC_GOT_HI) |
| .Case("GOT@HA", VK_PPC_GOT_HA) |
| .Case("got@ha", VK_PPC_GOT_HA) |
| .Case("TOCBASE", VK_PPC_TOCBASE) |
| .Case("tocbase", VK_PPC_TOCBASE) |
| .Case("TOC", VK_PPC_TOC) |
| .Case("toc", VK_PPC_TOC) |
| .Case("TOC@L", VK_PPC_TOC_LO) |
| .Case("toc@l", VK_PPC_TOC_LO) |
| .Case("TOC@H", VK_PPC_TOC_HI) |
| .Case("toc@h", VK_PPC_TOC_HI) |
| .Case("TOC@HA", VK_PPC_TOC_HA) |
| .Case("toc@ha", VK_PPC_TOC_HA) |
| .Case("TLS", VK_PPC_TLS) |
| .Case("tls", VK_PPC_TLS) |
| .Case("DTPMOD", VK_PPC_DTPMOD) |
| .Case("dtpmod", VK_PPC_DTPMOD) |
| .Case("TPREL", VK_PPC_TPREL) |
| .Case("tprel", VK_PPC_TPREL) |
| .Case("TPREL@L", VK_PPC_TPREL_LO) |
| .Case("tprel@l", VK_PPC_TPREL_LO) |
| .Case("TPREL@H", VK_PPC_TPREL_HI) |
| .Case("tprel@h", VK_PPC_TPREL_HI) |
| .Case("TPREL@HA", VK_PPC_TPREL_HA) |
| .Case("tprel@ha", VK_PPC_TPREL_HA) |
| .Case("TPREL@HIGHER", VK_PPC_TPREL_HIGHER) |
| .Case("tprel@higher", VK_PPC_TPREL_HIGHER) |
| .Case("TPREL@HIGHERA", VK_PPC_TPREL_HIGHERA) |
| .Case("tprel@highera", VK_PPC_TPREL_HIGHERA) |
| .Case("TPREL@HIGHEST", VK_PPC_TPREL_HIGHEST) |
| .Case("tprel@highest", VK_PPC_TPREL_HIGHEST) |
| .Case("TPREL@HIGHESTA", VK_PPC_TPREL_HIGHESTA) |
| .Case("tprel@highesta", VK_PPC_TPREL_HIGHESTA) |
| .Case("DTPREL", VK_PPC_DTPREL) |
| .Case("dtprel", VK_PPC_DTPREL) |
| .Case("DTPREL@L", VK_PPC_DTPREL_LO) |
| .Case("dtprel@l", VK_PPC_DTPREL_LO) |
| .Case("DTPREL@H", VK_PPC_DTPREL_HI) |
| .Case("dtprel@h", VK_PPC_DTPREL_HI) |
| .Case("DTPREL@HA", VK_PPC_DTPREL_HA) |
| .Case("dtprel@ha", VK_PPC_DTPREL_HA) |
| .Case("DTPREL@HIGHER", VK_PPC_DTPREL_HIGHER) |
| .Case("dtprel@higher", VK_PPC_DTPREL_HIGHER) |
| .Case("DTPREL@HIGHERA", VK_PPC_DTPREL_HIGHERA) |
| .Case("dtprel@highera", VK_PPC_DTPREL_HIGHERA) |
| .Case("DTPREL@HIGHEST", VK_PPC_DTPREL_HIGHEST) |
| .Case("dtprel@highest", VK_PPC_DTPREL_HIGHEST) |
| .Case("DTPREL@HIGHESTA", VK_PPC_DTPREL_HIGHESTA) |
| .Case("dtprel@highesta", VK_PPC_DTPREL_HIGHESTA) |
| .Case("GOT@TPREL", VK_PPC_GOT_TPREL) |
| .Case("got@tprel", VK_PPC_GOT_TPREL) |
| .Case("GOT@TPREL@L", VK_PPC_GOT_TPREL_LO) |
| .Case("got@tprel@l", VK_PPC_GOT_TPREL_LO) |
| .Case("GOT@TPREL@H", VK_PPC_GOT_TPREL_HI) |
| .Case("got@tprel@h", VK_PPC_GOT_TPREL_HI) |
| .Case("GOT@TPREL@HA", VK_PPC_GOT_TPREL_HA) |
| .Case("got@tprel@ha", VK_PPC_GOT_TPREL_HA) |
| .Case("GOT@DTPREL", VK_PPC_GOT_DTPREL) |
| .Case("got@dtprel", VK_PPC_GOT_DTPREL) |
| .Case("GOT@DTPREL@L", VK_PPC_GOT_DTPREL_LO) |
| .Case("got@dtprel@l", VK_PPC_GOT_DTPREL_LO) |
| .Case("GOT@DTPREL@H", VK_PPC_GOT_DTPREL_HI) |
| .Case("got@dtprel@h", VK_PPC_GOT_DTPREL_HI) |
| .Case("GOT@DTPREL@HA", VK_PPC_GOT_DTPREL_HA) |
| .Case("got@dtprel@ha", VK_PPC_GOT_DTPREL_HA) |
| .Case("GOT@TLSGD", VK_PPC_GOT_TLSGD) |
| .Case("got@tlsgd", VK_PPC_GOT_TLSGD) |
| .Case("GOT@TLSGD@L", VK_PPC_GOT_TLSGD_LO) |
| .Case("got@tlsgd@l", VK_PPC_GOT_TLSGD_LO) |
| .Case("GOT@TLSGD@H", VK_PPC_GOT_TLSGD_HI) |
| .Case("got@tlsgd@h", VK_PPC_GOT_TLSGD_HI) |
| .Case("GOT@TLSGD@HA", VK_PPC_GOT_TLSGD_HA) |
| .Case("got@tlsgd@ha", VK_PPC_GOT_TLSGD_HA) |
| .Case("GOT@TLSLD", VK_PPC_GOT_TLSLD) |
| .Case("got@tlsld", VK_PPC_GOT_TLSLD) |
| .Case("GOT@TLSLD@L", VK_PPC_GOT_TLSLD_LO) |
| .Case("got@tlsld@l", VK_PPC_GOT_TLSLD_LO) |
| .Case("GOT@TLSLD@H", VK_PPC_GOT_TLSLD_HI) |
| .Case("got@tlsld@h", VK_PPC_GOT_TLSLD_HI) |
| .Case("GOT@TLSLD@HA", VK_PPC_GOT_TLSLD_HA) |
| .Case("got@tlsld@ha", VK_PPC_GOT_TLSLD_HA) |
| .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; |
| |
| // Fast path constants. |
| if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(this)) { |
| Res = CE->getValue(); |
| return true; |
| } |
| |
| // FIXME: The use if InSet = Addrs is a hack. Setting InSet causes us |
| // absolutize differences across sections and that is what the MachO writer |
| // uses Addrs for. |
| bool IsRelocatable = |
| EvaluateAsRelocatableImpl(Value, Asm, Layout, Addrs, /*InSet*/ Addrs); |
| |
| // Record the current value. |
| Res = Value.getConstant(); |
| |
| return IsRelocatable && Value.isAbsolute(); |
| } |
| |
| /// \brief Helper method for \see EvaluateSymbolAdd(). |
| 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()); |
| |
| // Pointers to Thumb symbols need to have their low-bit set to allow |
| // for interworking. |
| if (Asm->isThumbFunc(&SA)) |
| Addend |= 1; |
| |
| // Clear the symbol expr pointers to indicate we have folded these |
| // operands. |
| A = B = 0; |
| return; |
| } |
| |
| if (!Layout) |
| return; |
| |
| const MCSectionData &SecA = *AD.getFragment()->getParent(); |
| const MCSectionData &SecB = *BD.getFragment()->getParent(); |
| |
| if ((&SecA != &SecB) && !Addrs) |
| return; |
| |
| // Eagerly evaluate. |
| Addend += (Layout->getSymbolOffset(&Asm->getSymbolData(A->getSymbol())) - |
| Layout->getSymbolOffset(&Asm->getSymbolData(B->getSymbol()))); |
| if (Addrs && (&SecA != &SecB)) |
| Addend += (Addrs->lookup(&SecA) - Addrs->lookup(&SecB)); |
| |
| // Pointers to Thumb symbols need to have their low-bit set to allow |
| // for interworking. |
| if (Asm->isThumbFunc(&SA)) |
| Addend |= 1; |
| |
| // Clear the symbol expr pointers to indicate we have folded these |
| // operands. |
| A = B = 0; |
| } |
| |
| /// \brief 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 aggresively 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. |
| 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) { |
| // FIXME: This routine (and other evaluation parts) are *incredibly* sloppy |
| // about dealing with modifiers. This will ultimately bite us, one day. |
| const MCSymbolRefExpr *LHS_A = LHS.getSymA(); |
| const MCSymbolRefExpr *LHS_B = LHS.getSymB(); |
| int64_t LHS_Cst = LHS.getConstant(); |
| |
| // Fold the result constant immediately. |
| int64_t Result_Cst = LHS_Cst + RHS_Cst; |
| |
| assert((!Layout || Asm) && |
| "Must have an assembler object if layout is given!"); |
| |
| // If we have a layout, we can fold resolved differences. |
| if (Asm) { |
| // First, fold out any differences which are fully resolved. By |
| // reassociating terms in |
| // Result = (LHS_A - LHS_B + LHS_Cst) + (RHS_A - RHS_B + RHS_Cst). |
| // we have the four possible differences: |
| // (LHS_A - LHS_B), |
| // (LHS_A - RHS_B), |
| // (RHS_A - LHS_B), |
| // (RHS_A - RHS_B). |
| // Since we are attempting to be as aggressive as possible about folding, we |
| // attempt to evaluate each possible alternative. |
| 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); |
| } |
| |
| // We can't represent the addition or subtraction of two symbols. |
| if ((LHS_A && RHS_A) || (LHS_B && RHS_B)) |
| return false; |
| |
| // At this point, we have at most one additive symbol and one subtractive |
| // symbol -- find them. |
| const MCSymbolRefExpr *A = LHS_A ? LHS_A : RHS_A; |
| const MCSymbolRefExpr *B = LHS_B ? LHS_B : RHS_B; |
| |
| // If we have a negated symbol, then we must have also have a non-negated |
| // symbol in order to encode the expression. |
| 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(); |
| |
| // Evaluate recursively if this is a variable. |
| if (Sym.isVariable() && SRE->getKind() == MCSymbolRefExpr::VK_None) { |
| bool Ret = Sym.getVariableValue()->EvaluateAsRelocatableImpl(Res, Asm, |
| Layout, |
| Addrs, |
| true); |
| // If we failed to simplify this to a constant, let the target |
| // handle it. |
| 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: |
| /// -(a - b + const) ==> (b - a - const) |
| 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; |
| |
| // We only support a few operations on non-constant expressions, handle |
| // those first. |
| if (!LHSValue.isAbsolute() || !RHSValue.isAbsolute()) { |
| switch (ABE->getOpcode()) { |
| default: |
| return false; |
| case MCBinaryExpr::Sub: |
| // Negate RHS and add. |
| 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); |
| } |
| } |
| |
| // FIXME: We need target hooks for the evaluation. It may be limited in |
| // width, and gas defines the result of comparisons and right shifts |
| // differently from Apple as. |
| 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; |
| } |
| } |
| |
| llvm_unreachable("Invalid assembly expression kind!"); |
| } |
| |
| const MCSection *MCExpr::FindAssociatedSection() const { |
| switch (getKind()) { |
| case Target: |
| // We never look through target specific expressions. |
| 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 either section is absolute, return the other. |
| if (LHS_S == MCSymbol::AbsolutePseudoSection) |
| return RHS_S; |
| if (RHS_S == MCSymbol::AbsolutePseudoSection) |
| return LHS_S; |
| |
| // Otherwise, return the first non-null section. |
| return LHS_S ? LHS_S : RHS_S; |
| } |
| } |
| |
| llvm_unreachable("Invalid assembly expression kind!"); |
| } |
