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-rw-r--r--contrib/llvm/lib/MC/MCExpr.cpp382
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diff --git a/contrib/llvm/lib/MC/MCExpr.cpp b/contrib/llvm/lib/MC/MCExpr.cpp
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+++ b/contrib/llvm/lib/MC/MCExpr.cpp
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+//===- 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/MCSymbol.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetAsmBackend.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();
+
+ if (SRE.getKind() == MCSymbolRefExpr::VK_ARM_HI16 ||
+ SRE.getKind() == MCSymbolRefExpr::VK_ARM_LO16)
+ OS << MCSymbolRefExpr::getVariantKindName(SRE.getKind());
+
+ // Parenthesize names that start with $ so that they don't look like
+ // absolute names.
+ if (Sym.getName()[0] == '$')
+ OS << '(' << Sym << ')';
+ else
+ OS << Sym;
+
+ if (SRE.getKind() != MCSymbolRefExpr::VK_None &&
+ SRE.getKind() != MCSymbolRefExpr::VK_ARM_HI16 &&
+ SRE.getKind() != MCSymbolRefExpr::VK_ARM_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);
+
+ // 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()) {
+ default: assert(0 && "Invalid opcode!");
+ 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;
+ }
+ }
+
+ 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_PLT: return "PLT";
+ case VK_TLSGD: return "TLSGD";
+ case VK_TPOFF: return "TPOFF";
+ case VK_ARM_HI16: return ":upper16:";
+ case VK_ARM_LO16: return ":lower16:";
+ case VK_TLVP: return "TLVP";
+ }
+}
+
+MCSymbolRefExpr::VariantKind
+MCSymbolRefExpr::getVariantKindForName(StringRef Name) {
+ return StringSwitch<VariantKind>(Name)
+ .Case("GOT", VK_GOT)
+ .Case("GOTOFF", VK_GOTOFF)
+ .Case("GOTPCREL", VK_GOTPCREL)
+ .Case("GOTTPOFF", VK_GOTTPOFF)
+ .Case("INDNTPOFF", VK_INDNTPOFF)
+ .Case("NTPOFF", VK_NTPOFF)
+ .Case("PLT", VK_PLT)
+ .Case("TLSGD", VK_TLSGD)
+ .Case("TPOFF", VK_TPOFF)
+ .Case("TLVP", VK_TLVP)
+ .Default(VK_Invalid);
+}
+
+/* *** */
+
+void MCTargetExpr::Anchor() {}
+
+/* *** */
+
+bool MCExpr::EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout *Layout) const {
+ MCValue Value;
+
+ // Fast path constants.
+ if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(this)) {
+ Res = CE->getValue();
+ return true;
+ }
+
+ if (!EvaluateAsRelocatable(Value, Layout) || !Value.isAbsolute())
+ return false;
+
+ Res = Value.getConstant();
+ return true;
+}
+
+static bool EvaluateSymbolicAdd(const MCValue &LHS,const MCSymbolRefExpr *RHS_A,
+ const MCSymbolRefExpr *RHS_B, int64_t RHS_Cst,
+ MCValue &Res) {
+ // We can't add or subtract two symbols.
+ if ((LHS.getSymA() && RHS_A) ||
+ (LHS.getSymB() && RHS_B))
+ return false;
+
+ const MCSymbolRefExpr *A = LHS.getSymA() ? LHS.getSymA() : RHS_A;
+ const MCSymbolRefExpr *B = LHS.getSymB() ? LHS.getSymB() : RHS_B;
+ if (B) {
+ // If we have a negated symbol, then we must have also have a non-negated
+ // symbol in order to encode the expression. We can do this check later to
+ // permit expressions which eventually fold to a representable form -- such
+ // as (a + (0 - b)) -- if necessary.
+ if (!A)
+ return false;
+ }
+ Res = MCValue::get(A, B, LHS.getConstant() + RHS_Cst);
+ return true;
+}
+
+bool MCExpr::EvaluateAsRelocatable(MCValue &Res,
+ const MCAsmLayout *Layout) 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()) {
+ if (!Sym.getVariableValue()->EvaluateAsRelocatable(Res, Layout))
+ return false;
+
+ // Absolutize symbol differences between defined symbols when we have a
+ // layout object and the target requests it.
+ if (Layout && Res.getSymB() &&
+ Layout->getAssembler().getBackend().hasAbsolutizedSet() &&
+ Res.getSymA()->getSymbol().isDefined() &&
+ Res.getSymB()->getSymbol().isDefined()) {
+ MCSymbolData &A =
+ Layout->getAssembler().getSymbolData(Res.getSymA()->getSymbol());
+ MCSymbolData &B =
+ Layout->getAssembler().getSymbolData(Res.getSymB()->getSymbol());
+ Res = MCValue::get(+ Layout->getSymbolAddress(&A)
+ - Layout->getSymbolAddress(&B)
+ + Res.getConstant());
+ }
+
+ return true;
+ }
+
+ Res = MCValue::get(SRE, 0, 0);
+ return true;
+ }
+
+ case Unary: {
+ const MCUnaryExpr *AUE = cast<MCUnaryExpr>(this);
+ MCValue Value;
+
+ if (!AUE->getSubExpr()->EvaluateAsRelocatable(Value, Layout))
+ 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()->EvaluateAsRelocatable(LHSValue, Layout) ||
+ !ABE->getRHS()->EvaluateAsRelocatable(RHSValue, Layout))
+ 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(LHSValue,
+ RHSValue.getSymB(), RHSValue.getSymA(),
+ -RHSValue.getConstant(),
+ Res);
+
+ case MCBinaryExpr::Add:
+ return EvaluateSymbolicAdd(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;
+ }
+ }
+
+ assert(0 && "Invalid assembly expression kind!");
+ return false;
+}
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