|  | //===--- RuntimeDyldChecker.cpp - RuntimeDyld tester framework --*- C++ -*-===// | 
|  | // | 
|  | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | 
|  | // See https://llvm.org/LICENSE.txt for license information. | 
|  | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | #include "llvm/ExecutionEngine/RuntimeDyldChecker.h" | 
|  | #include "RuntimeDyldCheckerImpl.h" | 
|  | #include "llvm/ADT/STLExtras.h" | 
|  | #include "llvm/MC/MCContext.h" | 
|  | #include "llvm/MC/MCDisassembler/MCDisassembler.h" | 
|  | #include "llvm/MC/MCInst.h" | 
|  | #include "llvm/Support/Endian.h" | 
|  | #include "llvm/Support/MSVCErrorWorkarounds.h" | 
|  | #include "llvm/Support/Path.h" | 
|  | #include <cctype> | 
|  | #include <memory> | 
|  | #include <utility> | 
|  |  | 
|  | #define DEBUG_TYPE "rtdyld" | 
|  |  | 
|  | using namespace llvm; | 
|  |  | 
|  | namespace llvm { | 
|  |  | 
|  | // Helper class that implements the language evaluated by RuntimeDyldChecker. | 
|  | class RuntimeDyldCheckerExprEval { | 
|  | public: | 
|  | RuntimeDyldCheckerExprEval(const RuntimeDyldCheckerImpl &Checker, | 
|  | raw_ostream &ErrStream) | 
|  | : Checker(Checker) {} | 
|  |  | 
|  | bool evaluate(StringRef Expr) const { | 
|  | // Expect equality expression of the form 'LHS = RHS'. | 
|  | Expr = Expr.trim(); | 
|  | size_t EQIdx = Expr.find('='); | 
|  |  | 
|  | ParseContext OutsideLoad(false); | 
|  |  | 
|  | // Evaluate LHS. | 
|  | StringRef LHSExpr = Expr.substr(0, EQIdx).rtrim(); | 
|  | StringRef RemainingExpr; | 
|  | EvalResult LHSResult; | 
|  | std::tie(LHSResult, RemainingExpr) = | 
|  | evalComplexExpr(evalSimpleExpr(LHSExpr, OutsideLoad), OutsideLoad); | 
|  | if (LHSResult.hasError()) | 
|  | return handleError(Expr, LHSResult); | 
|  | if (RemainingExpr != "") | 
|  | return handleError(Expr, unexpectedToken(RemainingExpr, LHSExpr, "")); | 
|  |  | 
|  | // Evaluate RHS. | 
|  | StringRef RHSExpr = Expr.substr(EQIdx + 1).ltrim(); | 
|  | EvalResult RHSResult; | 
|  | std::tie(RHSResult, RemainingExpr) = | 
|  | evalComplexExpr(evalSimpleExpr(RHSExpr, OutsideLoad), OutsideLoad); | 
|  | if (RHSResult.hasError()) | 
|  | return handleError(Expr, RHSResult); | 
|  | if (RemainingExpr != "") | 
|  | return handleError(Expr, unexpectedToken(RemainingExpr, RHSExpr, "")); | 
|  |  | 
|  | if (LHSResult.getValue() != RHSResult.getValue()) { | 
|  | Checker.ErrStream << "Expression '" << Expr << "' is false: " | 
|  | << format("0x%" PRIx64, LHSResult.getValue()) | 
|  | << " != " << format("0x%" PRIx64, RHSResult.getValue()) | 
|  | << "\n"; | 
|  | return false; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | private: | 
|  | // RuntimeDyldCheckerExprEval requires some context when parsing exprs. In | 
|  | // particular, it needs to know whether a symbol is being evaluated in the | 
|  | // context of a load, in which case we want the linker's local address for | 
|  | // the symbol, or outside of a load, in which case we want the symbol's | 
|  | // address in the remote target. | 
|  |  | 
|  | struct ParseContext { | 
|  | bool IsInsideLoad; | 
|  | ParseContext(bool IsInsideLoad) : IsInsideLoad(IsInsideLoad) {} | 
|  | }; | 
|  |  | 
|  | const RuntimeDyldCheckerImpl &Checker; | 
|  |  | 
|  | enum class BinOpToken : unsigned { | 
|  | Invalid, | 
|  | Add, | 
|  | Sub, | 
|  | BitwiseAnd, | 
|  | BitwiseOr, | 
|  | ShiftLeft, | 
|  | ShiftRight | 
|  | }; | 
|  |  | 
|  | class EvalResult { | 
|  | public: | 
|  | EvalResult() : Value(0), ErrorMsg("") {} | 
|  | EvalResult(uint64_t Value) : Value(Value), ErrorMsg("") {} | 
|  | EvalResult(std::string ErrorMsg) | 
|  | : Value(0), ErrorMsg(std::move(ErrorMsg)) {} | 
|  | uint64_t getValue() const { return Value; } | 
|  | bool hasError() const { return ErrorMsg != ""; } | 
|  | const std::string &getErrorMsg() const { return ErrorMsg; } | 
|  |  | 
|  | private: | 
|  | uint64_t Value; | 
|  | std::string ErrorMsg; | 
|  | }; | 
|  |  | 
|  | StringRef getTokenForError(StringRef Expr) const { | 
|  | if (Expr.empty()) | 
|  | return ""; | 
|  |  | 
|  | StringRef Token, Remaining; | 
|  | if (isalpha(Expr[0])) | 
|  | std::tie(Token, Remaining) = parseSymbol(Expr); | 
|  | else if (isdigit(Expr[0])) | 
|  | std::tie(Token, Remaining) = parseNumberString(Expr); | 
|  | else { | 
|  | unsigned TokLen = 1; | 
|  | if (Expr.startswith("<<") || Expr.startswith(">>")) | 
|  | TokLen = 2; | 
|  | Token = Expr.substr(0, TokLen); | 
|  | } | 
|  | return Token; | 
|  | } | 
|  |  | 
|  | EvalResult unexpectedToken(StringRef TokenStart, StringRef SubExpr, | 
|  | StringRef ErrText) const { | 
|  | std::string ErrorMsg("Encountered unexpected token '"); | 
|  | ErrorMsg += getTokenForError(TokenStart); | 
|  | if (SubExpr != "") { | 
|  | ErrorMsg += "' while parsing subexpression '"; | 
|  | ErrorMsg += SubExpr; | 
|  | } | 
|  | ErrorMsg += "'"; | 
|  | if (ErrText != "") { | 
|  | ErrorMsg += " "; | 
|  | ErrorMsg += ErrText; | 
|  | } | 
|  | return EvalResult(std::move(ErrorMsg)); | 
|  | } | 
|  |  | 
|  | bool handleError(StringRef Expr, const EvalResult &R) const { | 
|  | assert(R.hasError() && "Not an error result."); | 
|  | Checker.ErrStream << "Error evaluating expression '" << Expr | 
|  | << "': " << R.getErrorMsg() << "\n"; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | std::pair<BinOpToken, StringRef> parseBinOpToken(StringRef Expr) const { | 
|  | if (Expr.empty()) | 
|  | return std::make_pair(BinOpToken::Invalid, ""); | 
|  |  | 
|  | // Handle the two 2-character tokens. | 
|  | if (Expr.startswith("<<")) | 
|  | return std::make_pair(BinOpToken::ShiftLeft, Expr.substr(2).ltrim()); | 
|  | if (Expr.startswith(">>")) | 
|  | return std::make_pair(BinOpToken::ShiftRight, Expr.substr(2).ltrim()); | 
|  |  | 
|  | // Handle one-character tokens. | 
|  | BinOpToken Op; | 
|  | switch (Expr[0]) { | 
|  | default: | 
|  | return std::make_pair(BinOpToken::Invalid, Expr); | 
|  | case '+': | 
|  | Op = BinOpToken::Add; | 
|  | break; | 
|  | case '-': | 
|  | Op = BinOpToken::Sub; | 
|  | break; | 
|  | case '&': | 
|  | Op = BinOpToken::BitwiseAnd; | 
|  | break; | 
|  | case '|': | 
|  | Op = BinOpToken::BitwiseOr; | 
|  | break; | 
|  | } | 
|  |  | 
|  | return std::make_pair(Op, Expr.substr(1).ltrim()); | 
|  | } | 
|  |  | 
|  | EvalResult computeBinOpResult(BinOpToken Op, const EvalResult &LHSResult, | 
|  | const EvalResult &RHSResult) const { | 
|  | switch (Op) { | 
|  | default: | 
|  | llvm_unreachable("Tried to evaluate unrecognized operation."); | 
|  | case BinOpToken::Add: | 
|  | return EvalResult(LHSResult.getValue() + RHSResult.getValue()); | 
|  | case BinOpToken::Sub: | 
|  | return EvalResult(LHSResult.getValue() - RHSResult.getValue()); | 
|  | case BinOpToken::BitwiseAnd: | 
|  | return EvalResult(LHSResult.getValue() & RHSResult.getValue()); | 
|  | case BinOpToken::BitwiseOr: | 
|  | return EvalResult(LHSResult.getValue() | RHSResult.getValue()); | 
|  | case BinOpToken::ShiftLeft: | 
|  | return EvalResult(LHSResult.getValue() << RHSResult.getValue()); | 
|  | case BinOpToken::ShiftRight: | 
|  | return EvalResult(LHSResult.getValue() >> RHSResult.getValue()); | 
|  | } | 
|  | } | 
|  |  | 
|  | // Parse a symbol and return a (string, string) pair representing the symbol | 
|  | // name and expression remaining to be parsed. | 
|  | std::pair<StringRef, StringRef> parseSymbol(StringRef Expr) const { | 
|  | size_t FirstNonSymbol = Expr.find_first_not_of("0123456789" | 
|  | "abcdefghijklmnopqrstuvwxyz" | 
|  | "ABCDEFGHIJKLMNOPQRSTUVWXYZ" | 
|  | ":_.$"); | 
|  | return std::make_pair(Expr.substr(0, FirstNonSymbol), | 
|  | Expr.substr(FirstNonSymbol).ltrim()); | 
|  | } | 
|  |  | 
|  | // Evaluate a call to decode_operand. Decode the instruction operand at the | 
|  | // given symbol and get the value of the requested operand. | 
|  | // Returns an error if the instruction cannot be decoded, or the requested | 
|  | // operand is not an immediate. | 
|  | // On success, returns a pair containing the value of the operand, plus | 
|  | // the expression remaining to be evaluated. | 
|  | std::pair<EvalResult, StringRef> evalDecodeOperand(StringRef Expr) const { | 
|  | if (!Expr.startswith("(")) | 
|  | return std::make_pair(unexpectedToken(Expr, Expr, "expected '('"), ""); | 
|  | StringRef RemainingExpr = Expr.substr(1).ltrim(); | 
|  | StringRef Symbol; | 
|  | std::tie(Symbol, RemainingExpr) = parseSymbol(RemainingExpr); | 
|  |  | 
|  | if (!Checker.isSymbolValid(Symbol)) | 
|  | return std::make_pair( | 
|  | EvalResult(("Cannot decode unknown symbol '" + Symbol + "'").str()), | 
|  | ""); | 
|  |  | 
|  | if (!RemainingExpr.startswith(",")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, RemainingExpr, "expected ','"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | EvalResult OpIdxExpr; | 
|  | std::tie(OpIdxExpr, RemainingExpr) = evalNumberExpr(RemainingExpr); | 
|  | if (OpIdxExpr.hasError()) | 
|  | return std::make_pair(OpIdxExpr, ""); | 
|  |  | 
|  | if (!RemainingExpr.startswith(")")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, RemainingExpr, "expected ')'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | MCInst Inst; | 
|  | uint64_t Size; | 
|  | if (!decodeInst(Symbol, Inst, Size)) | 
|  | return std::make_pair( | 
|  | EvalResult(("Couldn't decode instruction at '" + Symbol + "'").str()), | 
|  | ""); | 
|  |  | 
|  | unsigned OpIdx = OpIdxExpr.getValue(); | 
|  | if (OpIdx >= Inst.getNumOperands()) { | 
|  | std::string ErrMsg; | 
|  | raw_string_ostream ErrMsgStream(ErrMsg); | 
|  | ErrMsgStream << "Invalid operand index '" << format("%i", OpIdx) | 
|  | << "' for instruction '" << Symbol | 
|  | << "'. Instruction has only " | 
|  | << format("%i", Inst.getNumOperands()) | 
|  | << " operands.\nInstruction is:\n  "; | 
|  | Inst.dump_pretty(ErrMsgStream, Checker.InstPrinter); | 
|  | return std::make_pair(EvalResult(ErrMsgStream.str()), ""); | 
|  | } | 
|  |  | 
|  | const MCOperand &Op = Inst.getOperand(OpIdx); | 
|  | if (!Op.isImm()) { | 
|  | std::string ErrMsg; | 
|  | raw_string_ostream ErrMsgStream(ErrMsg); | 
|  | ErrMsgStream << "Operand '" << format("%i", OpIdx) << "' of instruction '" | 
|  | << Symbol << "' is not an immediate.\nInstruction is:\n  "; | 
|  | Inst.dump_pretty(ErrMsgStream, Checker.InstPrinter); | 
|  |  | 
|  | return std::make_pair(EvalResult(ErrMsgStream.str()), ""); | 
|  | } | 
|  |  | 
|  | return std::make_pair(EvalResult(Op.getImm()), RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate a call to next_pc. | 
|  | // Decode the instruction at the given symbol and return the following program | 
|  | // counter. | 
|  | // Returns an error if the instruction cannot be decoded. | 
|  | // On success, returns a pair containing the next PC, plus of the | 
|  | // expression remaining to be evaluated. | 
|  | std::pair<EvalResult, StringRef> evalNextPC(StringRef Expr, | 
|  | ParseContext PCtx) const { | 
|  | if (!Expr.startswith("(")) | 
|  | return std::make_pair(unexpectedToken(Expr, Expr, "expected '('"), ""); | 
|  | StringRef RemainingExpr = Expr.substr(1).ltrim(); | 
|  | StringRef Symbol; | 
|  | std::tie(Symbol, RemainingExpr) = parseSymbol(RemainingExpr); | 
|  |  | 
|  | if (!Checker.isSymbolValid(Symbol)) | 
|  | return std::make_pair( | 
|  | EvalResult(("Cannot decode unknown symbol '" + Symbol + "'").str()), | 
|  | ""); | 
|  |  | 
|  | if (!RemainingExpr.startswith(")")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, RemainingExpr, "expected ')'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | MCInst Inst; | 
|  | uint64_t InstSize; | 
|  | if (!decodeInst(Symbol, Inst, InstSize)) | 
|  | return std::make_pair( | 
|  | EvalResult(("Couldn't decode instruction at '" + Symbol + "'").str()), | 
|  | ""); | 
|  |  | 
|  | uint64_t SymbolAddr = PCtx.IsInsideLoad | 
|  | ? Checker.getSymbolLocalAddr(Symbol) | 
|  | : Checker.getSymbolRemoteAddr(Symbol); | 
|  | uint64_t NextPC = SymbolAddr + InstSize; | 
|  |  | 
|  | return std::make_pair(EvalResult(NextPC), RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate a call to stub_addr/got_addr. | 
|  | // Look up and return the address of the stub for the given | 
|  | // (<file name>, <section name>, <symbol name>) tuple. | 
|  | // On success, returns a pair containing the stub address, plus the expression | 
|  | // remaining to be evaluated. | 
|  | std::pair<EvalResult, StringRef> | 
|  | evalStubOrGOTAddr(StringRef Expr, ParseContext PCtx, bool IsStubAddr) const { | 
|  | if (!Expr.startswith("(")) | 
|  | return std::make_pair(unexpectedToken(Expr, Expr, "expected '('"), ""); | 
|  | StringRef RemainingExpr = Expr.substr(1).ltrim(); | 
|  |  | 
|  | // Handle file-name specially, as it may contain characters that aren't | 
|  | // legal for symbols. | 
|  | StringRef StubContainerName; | 
|  | size_t ComaIdx = RemainingExpr.find(','); | 
|  | StubContainerName = RemainingExpr.substr(0, ComaIdx).rtrim(); | 
|  | RemainingExpr = RemainingExpr.substr(ComaIdx).ltrim(); | 
|  |  | 
|  | if (!RemainingExpr.startswith(",")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, Expr, "expected ','"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | StringRef Symbol; | 
|  | std::tie(Symbol, RemainingExpr) = parseSymbol(RemainingExpr); | 
|  |  | 
|  | if (!RemainingExpr.startswith(")")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, Expr, "expected ')'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | uint64_t StubAddr; | 
|  | std::string ErrorMsg = ""; | 
|  | std::tie(StubAddr, ErrorMsg) = Checker.getStubOrGOTAddrFor( | 
|  | StubContainerName, Symbol, PCtx.IsInsideLoad, IsStubAddr); | 
|  |  | 
|  | if (ErrorMsg != "") | 
|  | return std::make_pair(EvalResult(ErrorMsg), ""); | 
|  |  | 
|  | return std::make_pair(EvalResult(StubAddr), RemainingExpr); | 
|  | } | 
|  |  | 
|  | std::pair<EvalResult, StringRef> evalSectionAddr(StringRef Expr, | 
|  | ParseContext PCtx) const { | 
|  | if (!Expr.startswith("(")) | 
|  | return std::make_pair(unexpectedToken(Expr, Expr, "expected '('"), ""); | 
|  | StringRef RemainingExpr = Expr.substr(1).ltrim(); | 
|  |  | 
|  | // Handle file-name specially, as it may contain characters that aren't | 
|  | // legal for symbols. | 
|  | StringRef FileName; | 
|  | size_t ComaIdx = RemainingExpr.find(','); | 
|  | FileName = RemainingExpr.substr(0, ComaIdx).rtrim(); | 
|  | RemainingExpr = RemainingExpr.substr(ComaIdx).ltrim(); | 
|  |  | 
|  | if (!RemainingExpr.startswith(",")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, Expr, "expected ','"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | StringRef SectionName; | 
|  | std::tie(SectionName, RemainingExpr) = parseSymbol(RemainingExpr); | 
|  |  | 
|  | if (!RemainingExpr.startswith(")")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, Expr, "expected ')'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | uint64_t StubAddr; | 
|  | std::string ErrorMsg = ""; | 
|  | std::tie(StubAddr, ErrorMsg) = Checker.getSectionAddr( | 
|  | FileName, SectionName, PCtx.IsInsideLoad); | 
|  |  | 
|  | if (ErrorMsg != "") | 
|  | return std::make_pair(EvalResult(ErrorMsg), ""); | 
|  |  | 
|  | return std::make_pair(EvalResult(StubAddr), RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate an identiefer expr, which may be a symbol, or a call to | 
|  | // one of the builtin functions: get_insn_opcode or get_insn_length. | 
|  | // Return the result, plus the expression remaining to be parsed. | 
|  | std::pair<EvalResult, StringRef> evalIdentifierExpr(StringRef Expr, | 
|  | ParseContext PCtx) const { | 
|  | StringRef Symbol; | 
|  | StringRef RemainingExpr; | 
|  | std::tie(Symbol, RemainingExpr) = parseSymbol(Expr); | 
|  |  | 
|  | // Check for builtin function calls. | 
|  | if (Symbol == "decode_operand") | 
|  | return evalDecodeOperand(RemainingExpr); | 
|  | else if (Symbol == "next_pc") | 
|  | return evalNextPC(RemainingExpr, PCtx); | 
|  | else if (Symbol == "stub_addr") | 
|  | return evalStubOrGOTAddr(RemainingExpr, PCtx, true); | 
|  | else if (Symbol == "got_addr") | 
|  | return evalStubOrGOTAddr(RemainingExpr, PCtx, false); | 
|  | else if (Symbol == "section_addr") | 
|  | return evalSectionAddr(RemainingExpr, PCtx); | 
|  |  | 
|  | if (!Checker.isSymbolValid(Symbol)) { | 
|  | std::string ErrMsg("No known address for symbol '"); | 
|  | ErrMsg += Symbol; | 
|  | ErrMsg += "'"; | 
|  | if (Symbol.startswith("L")) | 
|  | ErrMsg += " (this appears to be an assembler local label - " | 
|  | " perhaps drop the 'L'?)"; | 
|  |  | 
|  | return std::make_pair(EvalResult(ErrMsg), ""); | 
|  | } | 
|  |  | 
|  | // The value for the symbol depends on the context we're evaluating in: | 
|  | // Inside a load this is the address in the linker's memory, outside a | 
|  | // load it's the address in the target processes memory. | 
|  | uint64_t Value = PCtx.IsInsideLoad ? Checker.getSymbolLocalAddr(Symbol) | 
|  | : Checker.getSymbolRemoteAddr(Symbol); | 
|  |  | 
|  | // Looks like a plain symbol reference. | 
|  | return std::make_pair(EvalResult(Value), RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Parse a number (hexadecimal or decimal) and return a (string, string) | 
|  | // pair representing the number and the expression remaining to be parsed. | 
|  | std::pair<StringRef, StringRef> parseNumberString(StringRef Expr) const { | 
|  | size_t FirstNonDigit = StringRef::npos; | 
|  | if (Expr.startswith("0x")) { | 
|  | FirstNonDigit = Expr.find_first_not_of("0123456789abcdefABCDEF", 2); | 
|  | if (FirstNonDigit == StringRef::npos) | 
|  | FirstNonDigit = Expr.size(); | 
|  | } else { | 
|  | FirstNonDigit = Expr.find_first_not_of("0123456789"); | 
|  | if (FirstNonDigit == StringRef::npos) | 
|  | FirstNonDigit = Expr.size(); | 
|  | } | 
|  | return std::make_pair(Expr.substr(0, FirstNonDigit), | 
|  | Expr.substr(FirstNonDigit)); | 
|  | } | 
|  |  | 
|  | // Evaluate a constant numeric expression (hexadecimal or decimal) and | 
|  | // return a pair containing the result, and the expression remaining to be | 
|  | // evaluated. | 
|  | std::pair<EvalResult, StringRef> evalNumberExpr(StringRef Expr) const { | 
|  | StringRef ValueStr; | 
|  | StringRef RemainingExpr; | 
|  | std::tie(ValueStr, RemainingExpr) = parseNumberString(Expr); | 
|  |  | 
|  | if (ValueStr.empty() || !isdigit(ValueStr[0])) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, RemainingExpr, "expected number"), ""); | 
|  | uint64_t Value; | 
|  | ValueStr.getAsInteger(0, Value); | 
|  | return std::make_pair(EvalResult(Value), RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate an expression of the form "(<expr>)" and return a pair | 
|  | // containing the result of evaluating <expr>, plus the expression | 
|  | // remaining to be parsed. | 
|  | std::pair<EvalResult, StringRef> evalParensExpr(StringRef Expr, | 
|  | ParseContext PCtx) const { | 
|  | assert(Expr.startswith("(") && "Not a parenthesized expression"); | 
|  | EvalResult SubExprResult; | 
|  | StringRef RemainingExpr; | 
|  | std::tie(SubExprResult, RemainingExpr) = | 
|  | evalComplexExpr(evalSimpleExpr(Expr.substr(1).ltrim(), PCtx), PCtx); | 
|  | if (SubExprResult.hasError()) | 
|  | return std::make_pair(SubExprResult, ""); | 
|  | if (!RemainingExpr.startswith(")")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, Expr, "expected ')'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  | return std::make_pair(SubExprResult, RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate an expression in one of the following forms: | 
|  | //   *{<number>}<expr> | 
|  | // Return a pair containing the result, plus the expression remaining to be | 
|  | // parsed. | 
|  | std::pair<EvalResult, StringRef> evalLoadExpr(StringRef Expr) const { | 
|  | assert(Expr.startswith("*") && "Not a load expression"); | 
|  | StringRef RemainingExpr = Expr.substr(1).ltrim(); | 
|  |  | 
|  | // Parse read size. | 
|  | if (!RemainingExpr.startswith("{")) | 
|  | return std::make_pair(EvalResult("Expected '{' following '*'."), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  | EvalResult ReadSizeExpr; | 
|  | std::tie(ReadSizeExpr, RemainingExpr) = evalNumberExpr(RemainingExpr); | 
|  | if (ReadSizeExpr.hasError()) | 
|  | return std::make_pair(ReadSizeExpr, RemainingExpr); | 
|  | uint64_t ReadSize = ReadSizeExpr.getValue(); | 
|  | if (ReadSize < 1 || ReadSize > 8) | 
|  | return std::make_pair(EvalResult("Invalid size for dereference."), ""); | 
|  | if (!RemainingExpr.startswith("}")) | 
|  | return std::make_pair(EvalResult("Missing '}' for dereference."), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | // Evaluate the expression representing the load address. | 
|  | ParseContext LoadCtx(true); | 
|  | EvalResult LoadAddrExprResult; | 
|  | std::tie(LoadAddrExprResult, RemainingExpr) = | 
|  | evalComplexExpr(evalSimpleExpr(RemainingExpr, LoadCtx), LoadCtx); | 
|  |  | 
|  | if (LoadAddrExprResult.hasError()) | 
|  | return std::make_pair(LoadAddrExprResult, ""); | 
|  |  | 
|  | uint64_t LoadAddr = LoadAddrExprResult.getValue(); | 
|  |  | 
|  | // If there is no error but the content pointer is null then this is a | 
|  | // zero-fill symbol/section. | 
|  | if (LoadAddr == 0) | 
|  | return std::make_pair(0, RemainingExpr); | 
|  |  | 
|  | return std::make_pair( | 
|  | EvalResult(Checker.readMemoryAtAddr(LoadAddr, ReadSize)), | 
|  | RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate a "simple" expression. This is any expression that _isn't_ an | 
|  | // un-parenthesized binary expression. | 
|  | // | 
|  | // "Simple" expressions can be optionally bit-sliced. See evalSlicedExpr. | 
|  | // | 
|  | // Returns a pair containing the result of the evaluation, plus the | 
|  | // expression remaining to be parsed. | 
|  | std::pair<EvalResult, StringRef> evalSimpleExpr(StringRef Expr, | 
|  | ParseContext PCtx) const { | 
|  | EvalResult SubExprResult; | 
|  | StringRef RemainingExpr; | 
|  |  | 
|  | if (Expr.empty()) | 
|  | return std::make_pair(EvalResult("Unexpected end of expression"), ""); | 
|  |  | 
|  | if (Expr[0] == '(') | 
|  | std::tie(SubExprResult, RemainingExpr) = evalParensExpr(Expr, PCtx); | 
|  | else if (Expr[0] == '*') | 
|  | std::tie(SubExprResult, RemainingExpr) = evalLoadExpr(Expr); | 
|  | else if (isalpha(Expr[0]) || Expr[0] == '_') | 
|  | std::tie(SubExprResult, RemainingExpr) = evalIdentifierExpr(Expr, PCtx); | 
|  | else if (isdigit(Expr[0])) | 
|  | std::tie(SubExprResult, RemainingExpr) = evalNumberExpr(Expr); | 
|  | else | 
|  | return std::make_pair( | 
|  | unexpectedToken(Expr, Expr, | 
|  | "expected '(', '*', identifier, or number"), ""); | 
|  |  | 
|  | if (SubExprResult.hasError()) | 
|  | return std::make_pair(SubExprResult, RemainingExpr); | 
|  |  | 
|  | // Evaluate bit-slice if present. | 
|  | if (RemainingExpr.startswith("[")) | 
|  | std::tie(SubExprResult, RemainingExpr) = | 
|  | evalSliceExpr(std::make_pair(SubExprResult, RemainingExpr)); | 
|  |  | 
|  | return std::make_pair(SubExprResult, RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate a bit-slice of an expression. | 
|  | // A bit-slice has the form "<expr>[high:low]". The result of evaluating a | 
|  | // slice is the bits between high and low (inclusive) in the original | 
|  | // expression, right shifted so that the "low" bit is in position 0 in the | 
|  | // result. | 
|  | // Returns a pair containing the result of the slice operation, plus the | 
|  | // expression remaining to be parsed. | 
|  | std::pair<EvalResult, StringRef> | 
|  | evalSliceExpr(const std::pair<EvalResult, StringRef> &Ctx) const { | 
|  | EvalResult SubExprResult; | 
|  | StringRef RemainingExpr; | 
|  | std::tie(SubExprResult, RemainingExpr) = Ctx; | 
|  |  | 
|  | assert(RemainingExpr.startswith("[") && "Not a slice expr."); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | EvalResult HighBitExpr; | 
|  | std::tie(HighBitExpr, RemainingExpr) = evalNumberExpr(RemainingExpr); | 
|  |  | 
|  | if (HighBitExpr.hasError()) | 
|  | return std::make_pair(HighBitExpr, RemainingExpr); | 
|  |  | 
|  | if (!RemainingExpr.startswith(":")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, RemainingExpr, "expected ':'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | EvalResult LowBitExpr; | 
|  | std::tie(LowBitExpr, RemainingExpr) = evalNumberExpr(RemainingExpr); | 
|  |  | 
|  | if (LowBitExpr.hasError()) | 
|  | return std::make_pair(LowBitExpr, RemainingExpr); | 
|  |  | 
|  | if (!RemainingExpr.startswith("]")) | 
|  | return std::make_pair( | 
|  | unexpectedToken(RemainingExpr, RemainingExpr, "expected ']'"), ""); | 
|  | RemainingExpr = RemainingExpr.substr(1).ltrim(); | 
|  |  | 
|  | unsigned HighBit = HighBitExpr.getValue(); | 
|  | unsigned LowBit = LowBitExpr.getValue(); | 
|  | uint64_t Mask = ((uint64_t)1 << (HighBit - LowBit + 1)) - 1; | 
|  | uint64_t SlicedValue = (SubExprResult.getValue() >> LowBit) & Mask; | 
|  | return std::make_pair(EvalResult(SlicedValue), RemainingExpr); | 
|  | } | 
|  |  | 
|  | // Evaluate a "complex" expression. | 
|  | // Takes an already evaluated subexpression and checks for the presence of a | 
|  | // binary operator, computing the result of the binary operation if one is | 
|  | // found. Used to make arithmetic expressions left-associative. | 
|  | // Returns a pair containing the ultimate result of evaluating the | 
|  | // expression, plus the expression remaining to be evaluated. | 
|  | std::pair<EvalResult, StringRef> | 
|  | evalComplexExpr(const std::pair<EvalResult, StringRef> &LHSAndRemaining, | 
|  | ParseContext PCtx) const { | 
|  | EvalResult LHSResult; | 
|  | StringRef RemainingExpr; | 
|  | std::tie(LHSResult, RemainingExpr) = LHSAndRemaining; | 
|  |  | 
|  | // If there was an error, or there's nothing left to evaluate, return the | 
|  | // result. | 
|  | if (LHSResult.hasError() || RemainingExpr == "") | 
|  | return std::make_pair(LHSResult, RemainingExpr); | 
|  |  | 
|  | // Otherwise check if this is a binary expressioan. | 
|  | BinOpToken BinOp; | 
|  | std::tie(BinOp, RemainingExpr) = parseBinOpToken(RemainingExpr); | 
|  |  | 
|  | // If this isn't a recognized expression just return. | 
|  | if (BinOp == BinOpToken::Invalid) | 
|  | return std::make_pair(LHSResult, RemainingExpr); | 
|  |  | 
|  | // This is a recognized bin-op. Evaluate the RHS, then evaluate the binop. | 
|  | EvalResult RHSResult; | 
|  | std::tie(RHSResult, RemainingExpr) = evalSimpleExpr(RemainingExpr, PCtx); | 
|  |  | 
|  | // If there was an error evaluating the RHS, return it. | 
|  | if (RHSResult.hasError()) | 
|  | return std::make_pair(RHSResult, RemainingExpr); | 
|  |  | 
|  | // This is a binary expression - evaluate and try to continue as a | 
|  | // complex expr. | 
|  | EvalResult ThisResult(computeBinOpResult(BinOp, LHSResult, RHSResult)); | 
|  |  | 
|  | return evalComplexExpr(std::make_pair(ThisResult, RemainingExpr), PCtx); | 
|  | } | 
|  |  | 
|  | bool decodeInst(StringRef Symbol, MCInst &Inst, uint64_t &Size) const { | 
|  | MCDisassembler *Dis = Checker.Disassembler; | 
|  | StringRef SymbolMem = Checker.getSymbolContent(Symbol); | 
|  | ArrayRef<uint8_t> SymbolBytes(SymbolMem.bytes_begin(), SymbolMem.size()); | 
|  |  | 
|  | MCDisassembler::DecodeStatus S = | 
|  | Dis->getInstruction(Inst, Size, SymbolBytes, 0, nulls()); | 
|  |  | 
|  | return (S == MCDisassembler::Success); | 
|  | } | 
|  | }; | 
|  | } | 
|  |  | 
|  | RuntimeDyldCheckerImpl::RuntimeDyldCheckerImpl( | 
|  | IsSymbolValidFunction IsSymbolValid, GetSymbolInfoFunction GetSymbolInfo, | 
|  | GetSectionInfoFunction GetSectionInfo, GetStubInfoFunction GetStubInfo, | 
|  | GetGOTInfoFunction GetGOTInfo, support::endianness Endianness, | 
|  | MCDisassembler *Disassembler, MCInstPrinter *InstPrinter, | 
|  | raw_ostream &ErrStream) | 
|  | : IsSymbolValid(std::move(IsSymbolValid)), | 
|  | GetSymbolInfo(std::move(GetSymbolInfo)), | 
|  | GetSectionInfo(std::move(GetSectionInfo)), | 
|  | GetStubInfo(std::move(GetStubInfo)), GetGOTInfo(std::move(GetGOTInfo)), | 
|  | Endianness(Endianness), Disassembler(Disassembler), | 
|  | InstPrinter(InstPrinter), ErrStream(ErrStream) {} | 
|  |  | 
|  | bool RuntimeDyldCheckerImpl::check(StringRef CheckExpr) const { | 
|  | CheckExpr = CheckExpr.trim(); | 
|  | LLVM_DEBUG(dbgs() << "RuntimeDyldChecker: Checking '" << CheckExpr | 
|  | << "'...\n"); | 
|  | RuntimeDyldCheckerExprEval P(*this, ErrStream); | 
|  | bool Result = P.evaluate(CheckExpr); | 
|  | (void)Result; | 
|  | LLVM_DEBUG(dbgs() << "RuntimeDyldChecker: '" << CheckExpr << "' " | 
|  | << (Result ? "passed" : "FAILED") << ".\n"); | 
|  | return Result; | 
|  | } | 
|  |  | 
|  | bool RuntimeDyldCheckerImpl::checkAllRulesInBuffer(StringRef RulePrefix, | 
|  | MemoryBuffer *MemBuf) const { | 
|  | bool DidAllTestsPass = true; | 
|  | unsigned NumRules = 0; | 
|  |  | 
|  | const char *LineStart = MemBuf->getBufferStart(); | 
|  |  | 
|  | // Eat whitespace. | 
|  | while (LineStart != MemBuf->getBufferEnd() && std::isspace(*LineStart)) | 
|  | ++LineStart; | 
|  |  | 
|  | while (LineStart != MemBuf->getBufferEnd() && *LineStart != '\0') { | 
|  | const char *LineEnd = LineStart; | 
|  | while (LineEnd != MemBuf->getBufferEnd() && *LineEnd != '\r' && | 
|  | *LineEnd != '\n') | 
|  | ++LineEnd; | 
|  |  | 
|  | StringRef Line(LineStart, LineEnd - LineStart); | 
|  | if (Line.startswith(RulePrefix)) { | 
|  | DidAllTestsPass &= check(Line.substr(RulePrefix.size())); | 
|  | ++NumRules; | 
|  | } | 
|  |  | 
|  | // Eat whitespace. | 
|  | LineStart = LineEnd; | 
|  | while (LineStart != MemBuf->getBufferEnd() && std::isspace(*LineStart)) | 
|  | ++LineStart; | 
|  | } | 
|  | return DidAllTestsPass && (NumRules != 0); | 
|  | } | 
|  |  | 
|  | bool RuntimeDyldCheckerImpl::isSymbolValid(StringRef Symbol) const { | 
|  | return IsSymbolValid(Symbol); | 
|  | } | 
|  |  | 
|  | uint64_t RuntimeDyldCheckerImpl::getSymbolLocalAddr(StringRef Symbol) const { | 
|  | auto SymInfo = GetSymbolInfo(Symbol); | 
|  | if (!SymInfo) { | 
|  | logAllUnhandledErrors(SymInfo.takeError(), errs(), "RTDyldChecker: "); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (SymInfo->isZeroFill()) | 
|  | return 0; | 
|  |  | 
|  | return static_cast<uint64_t>( | 
|  | reinterpret_cast<uintptr_t>(SymInfo->getContent().data())); | 
|  | } | 
|  |  | 
|  | uint64_t RuntimeDyldCheckerImpl::getSymbolRemoteAddr(StringRef Symbol) const { | 
|  | auto SymInfo = GetSymbolInfo(Symbol); | 
|  | if (!SymInfo) { | 
|  | logAllUnhandledErrors(SymInfo.takeError(), errs(), "RTDyldChecker: "); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | return SymInfo->getTargetAddress(); | 
|  | } | 
|  |  | 
|  | uint64_t RuntimeDyldCheckerImpl::readMemoryAtAddr(uint64_t SrcAddr, | 
|  | unsigned Size) const { | 
|  | uintptr_t PtrSizedAddr = static_cast<uintptr_t>(SrcAddr); | 
|  | assert(PtrSizedAddr == SrcAddr && "Linker memory pointer out-of-range."); | 
|  | void *Ptr = reinterpret_cast<void*>(PtrSizedAddr); | 
|  |  | 
|  | switch (Size) { | 
|  | case 1: | 
|  | return support::endian::read<uint8_t>(Ptr, Endianness); | 
|  | case 2: | 
|  | return support::endian::read<uint16_t>(Ptr, Endianness); | 
|  | case 4: | 
|  | return support::endian::read<uint32_t>(Ptr, Endianness); | 
|  | case 8: | 
|  | return support::endian::read<uint64_t>(Ptr, Endianness); | 
|  | } | 
|  | llvm_unreachable("Unsupported read size"); | 
|  | } | 
|  |  | 
|  | StringRef RuntimeDyldCheckerImpl::getSymbolContent(StringRef Symbol) const { | 
|  | auto SymInfo = GetSymbolInfo(Symbol); | 
|  | if (!SymInfo) { | 
|  | logAllUnhandledErrors(SymInfo.takeError(), errs(), "RTDyldChecker: "); | 
|  | return StringRef(); | 
|  | } | 
|  | return SymInfo->getContent(); | 
|  | } | 
|  |  | 
|  | std::pair<uint64_t, std::string> RuntimeDyldCheckerImpl::getSectionAddr( | 
|  | StringRef FileName, StringRef SectionName, bool IsInsideLoad) const { | 
|  |  | 
|  | auto SecInfo = GetSectionInfo(FileName, SectionName); | 
|  | if (!SecInfo) { | 
|  | std::string ErrMsg; | 
|  | { | 
|  | raw_string_ostream ErrMsgStream(ErrMsg); | 
|  | logAllUnhandledErrors(SecInfo.takeError(), ErrMsgStream, | 
|  | "RTDyldChecker: "); | 
|  | } | 
|  | return std::make_pair(0, std::move(ErrMsg)); | 
|  | } | 
|  |  | 
|  | // If this address is being looked up in "load" mode, return the content | 
|  | // pointer, otherwise return the target address. | 
|  |  | 
|  | uint64_t Addr = 0; | 
|  |  | 
|  | if (IsInsideLoad) { | 
|  | if (SecInfo->isZeroFill()) | 
|  | Addr = 0; | 
|  | else | 
|  | Addr = pointerToJITTargetAddress(SecInfo->getContent().data()); | 
|  | } else | 
|  | Addr = SecInfo->getTargetAddress(); | 
|  |  | 
|  | return std::make_pair(Addr, ""); | 
|  | } | 
|  |  | 
|  | std::pair<uint64_t, std::string> RuntimeDyldCheckerImpl::getStubOrGOTAddrFor( | 
|  | StringRef StubContainerName, StringRef SymbolName, bool IsInsideLoad, | 
|  | bool IsStubAddr) const { | 
|  |  | 
|  | auto StubInfo = IsStubAddr ? GetStubInfo(StubContainerName, SymbolName) | 
|  | : GetGOTInfo(StubContainerName, SymbolName); | 
|  |  | 
|  | if (!StubInfo) { | 
|  | std::string ErrMsg; | 
|  | { | 
|  | raw_string_ostream ErrMsgStream(ErrMsg); | 
|  | logAllUnhandledErrors(StubInfo.takeError(), ErrMsgStream, | 
|  | "RTDyldChecker: "); | 
|  | } | 
|  | return std::make_pair((uint64_t)0, std::move(ErrMsg)); | 
|  | } | 
|  |  | 
|  | uint64_t Addr = 0; | 
|  |  | 
|  | if (IsInsideLoad) { | 
|  | if (StubInfo->isZeroFill()) | 
|  | return std::make_pair((uint64_t)0, "Detected zero-filled stub/GOT entry"); | 
|  | Addr = pointerToJITTargetAddress(StubInfo->getContent().data()); | 
|  | } else | 
|  | Addr = StubInfo->getTargetAddress(); | 
|  |  | 
|  | return std::make_pair(Addr, ""); | 
|  | } | 
|  |  | 
|  | RuntimeDyldChecker::RuntimeDyldChecker( | 
|  | IsSymbolValidFunction IsSymbolValid, GetSymbolInfoFunction GetSymbolInfo, | 
|  | GetSectionInfoFunction GetSectionInfo, GetStubInfoFunction GetStubInfo, | 
|  | GetGOTInfoFunction GetGOTInfo, support::endianness Endianness, | 
|  | MCDisassembler *Disassembler, MCInstPrinter *InstPrinter, | 
|  | raw_ostream &ErrStream) | 
|  | : Impl(::std::make_unique<RuntimeDyldCheckerImpl>( | 
|  | std::move(IsSymbolValid), std::move(GetSymbolInfo), | 
|  | std::move(GetSectionInfo), std::move(GetStubInfo), | 
|  | std::move(GetGOTInfo), Endianness, Disassembler, InstPrinter, | 
|  | ErrStream)) {} | 
|  |  | 
|  | RuntimeDyldChecker::~RuntimeDyldChecker() {} | 
|  |  | 
|  | bool RuntimeDyldChecker::check(StringRef CheckExpr) const { | 
|  | return Impl->check(CheckExpr); | 
|  | } | 
|  |  | 
|  | bool RuntimeDyldChecker::checkAllRulesInBuffer(StringRef RulePrefix, | 
|  | MemoryBuffer *MemBuf) const { | 
|  | return Impl->checkAllRulesInBuffer(RulePrefix, MemBuf); | 
|  | } | 
|  |  | 
|  | std::pair<uint64_t, std::string> | 
|  | RuntimeDyldChecker::getSectionAddr(StringRef FileName, StringRef SectionName, | 
|  | bool LocalAddress) { | 
|  | return Impl->getSectionAddr(FileName, SectionName, LocalAddress); | 
|  | } |