ASTNode ArrayTransformer::TransformTerm(const ASTNode& term) { assert(TransformMap != NULL); const Kind k = term.GetKind(); if (!is_Term_kind(k)) FatalError("TransformTerm: Illegal kind: You have input a nonterm:", term, k); ASTNodeMap::const_iterator iter; if ((iter = TransformMap->find(term)) != TransformMap->end()) return iter->second; ASTNode result; switch (k) { case SYMBOL: case BVCONST: { result = term; break; } case WRITE: FatalError("TransformTerm: this kind is not supported", term); break; case READ: result = TransformArrayRead(term); break; case ITE: { ASTNode cond = term[0]; ASTNode thn = term[1]; ASTNode els = term[2]; cond = TransformFormula(cond); if (ASTTrue == cond) result = TransformTerm(thn); else if (ASTFalse == cond) result = TransformTerm(els); else { thn = TransformTerm(thn); els = TransformTerm(els); if (bm->UserFlags.optimize_flag) result = simp->CreateSimplifiedTermITE(cond, thn, els); else result = nf->CreateTerm(ITE, thn.GetValueWidth(), cond, thn, els); } assert(result.GetIndexWidth() == term.GetIndexWidth()); break; } default: { const ASTVec& c = term.GetChildren(); ASTVec::const_iterator it = c.begin(); ASTVec::const_iterator itend = c.end(); const unsigned width = term.GetValueWidth(); const unsigned indexwidth = term.GetIndexWidth(); ASTVec o; o.reserve(c.size()); for (; it != itend; it++) { o.push_back(TransformTerm(*it)); } if (c != o) { result = nf->CreateArrayTerm(k, indexwidth, width, o); } else result = term; } break; } if (term.Degree() > 0) (*TransformMap)[term] = result; if (term.GetValueWidth() != result.GetValueWidth()) FatalError("TransformTerm: " "result and input terms are of different length", result); if (term.GetIndexWidth() != result.GetIndexWidth()) { std::cerr << "TransformTerm: input term is : " << term << std::endl; FatalError("TransformTerm: " "result & input terms have different index length", result); } return result; }
/* FUNCTION: Typechecker for terms and formulas * * TypeChecker: Assumes that the immediate Children of the input * ASTNode have been typechecked. This function is suitable in * scenarios like where you are building the ASTNode Tree, and you * typecheck as you go along. It is not suitable as a general * typechecker. * * If this returns, this ALWAYS returns true. If there is an error it * will call FatalError() and abort. */ bool BVTypeCheck(const ASTNode& n) { Kind k = n.GetKind(); //The children of bitvector terms are in turn bitvectors. const ASTVec& v = n.GetChildren(); if (is_Term_kind(k)) { switch (k) { case BVCONST: if (BITVECTOR_TYPE != n.GetType()) FatalError("BVTypeCheck: The term t does not typecheck, where t = \n", n); break; case SYMBOL: return true; case ITE: if (n.Degree() != 3) FatalError("BVTypeCheck: should have exactly 3 args\n", n); if (BOOLEAN_TYPE != n[0].GetType() || (n[1].GetType() != n[2].GetType())) FatalError("BVTypeCheck: The term t does not typecheck, where t = \n", n); if (n[1].GetValueWidth() != n[2].GetValueWidth()) FatalError("BVTypeCheck: length of THENbranch != length of ELSEbranch in the term t = \n", n); if (n[1].GetIndexWidth() != n[2].GetIndexWidth()) FatalError("BVTypeCheck: length of THENbranch != length of ELSEbranch in the term t = \n", n); break; case READ: if (n.GetChildren().size() !=2) FatalError("2 params to read."); if (n[0].GetIndexWidth() != n[1].GetValueWidth()) { cerr << "Length of indexwidth of array: " << n[0] << " is : " << n[0].GetIndexWidth() << endl; cerr << "Length of the actual index is: " << n[1] << " is : " << n[1].GetValueWidth() << endl; FatalError("BVTypeCheck: length of indexwidth of array != length of actual index in the term t = \n", n); } if (ARRAY_TYPE != n[0].GetType()) FatalError("First parameter to read should be an array", n[0]); if (BITVECTOR_TYPE != n[1].GetType()) FatalError("Second parameter to read should be a bitvector", n[1]); break; case WRITE: if (n.GetChildren().size() !=3) FatalError("3 params to write."); if (n[0].GetIndexWidth() != n[1].GetValueWidth()) FatalError("BVTypeCheck: length of indexwidth of array != length of actual index in the term t = \n", n); if (n[0].GetValueWidth() != n[2].GetValueWidth()) FatalError("BVTypeCheck: valuewidth of array != length of actual value in the term t = \n", n); if (ARRAY_TYPE != n[0].GetType()) FatalError("First parameter to read should be an array", n[0]); if (BITVECTOR_TYPE != n[1].GetType()) FatalError("Second parameter to read should be a bitvector", n[1]); if (BITVECTOR_TYPE != n[2].GetType()) FatalError("Third parameter to read should be a bitvector", n[2]); break; case BVDIV: case BVMOD: case BVSUB: case SBVDIV: case SBVREM: case SBVMOD: case BVLEFTSHIFT: case BVRIGHTSHIFT: case BVSRSHIFT: case BVVARSHIFT: if (n.Degree() != 2) FatalError("BVTypeCheck: should have exactly 2 args\n", n); // run on. case BVOR: case BVAND: case BVXOR: case BVNOR: case BVNAND: case BVXNOR: case BVPLUS: case BVMULT: { if (!(v.size() >= 2)) FatalError("BVTypeCheck:bitwise Booleans and BV arith operators must have at least two arguments\n", n); unsigned int width = n.GetValueWidth(); for (ASTVec::const_iterator it = v.begin(), itend = v.end(); it != itend; it++) { if (width != it->GetValueWidth()) { cerr << "BVTypeCheck:Operands of bitwise-Booleans and BV arith operators must be of equal length\n"; cerr << n << endl; cerr << "width of term:" << width << endl; cerr << "width of offending operand:" << it->GetValueWidth() << endl; FatalError("BVTypeCheck:Offending operand:\n", *it); } if (BITVECTOR_TYPE != it->GetType()) FatalError("BVTypeCheck: ChildNodes of bitvector-terms must be bitvectors\n", n); } break; } case BVSX: case BVZX: //in BVSX(n[0],len), the length of the BVSX term must be //greater than the length of n[0] if (n[0].GetValueWidth() > n.GetValueWidth()) { FatalError( "BVTypeCheck: BV[SZ]X(t,bv[sz]x_len) : length of 't' must be <= bv[sz]x_len\n", n); } if ((v.size() != 2)) FatalError( "BVTypeCheck:BV[SZ]X must have two arguments. The second is the new width\n", n); break; case BVCONCAT: checkChildrenAreBV(v, n); if (n.Degree() != 2) FatalError("BVTypeCheck: should have exactly 2 args\n", n); if (n.GetValueWidth() != n[0].GetValueWidth() + n[1].GetValueWidth()) FatalError("BVTypeCheck:BVCONCAT: lengths do not add up\n", n); break; case BVUMINUS: case BVNEG: checkChildrenAreBV(v, n); if (n.Degree() != 1) FatalError("BVTypeCheck: should have exactly 1 args\n", n); break; case BVEXTRACT: checkChildrenAreBV(v, n); if (n.Degree() != 3) FatalError("BVTypeCheck: should have exactly 3 args\n", n); if (!(BVCONST == n[1].GetKind() && BVCONST == n[2].GetKind())) FatalError("BVTypeCheck: indices should be BVCONST\n", n); if (n.GetValueWidth() != n[1].GetUnsignedConst() - n[2].GetUnsignedConst() + 1) FatalError("BVTypeCheck: length mismatch\n", n); if (n[1].GetUnsignedConst() >= n[0].GetValueWidth()) FatalError( "BVTypeCheck: Top index of select is greater or equal to the bitwidth.\n", n); break; default: cerr << _kind_names[k]; FatalError("No type checking for type"); break; } } else { if (!(is_Form_kind(k) && BOOLEAN_TYPE == n.GetType())) FatalError("BVTypeCheck: not a formula:", n); switch (k) { case TRUE: case FALSE: case SYMBOL: return true; case BOOLEXTRACT: checkChildrenAreBV(v, n); if (n.Degree() != 2) FatalError("BVTypeCheck: should have exactly 2 args\n", n); if (!(BVCONST == n[1].GetKind())) FatalError("BVTypeCheck: index should be BVCONST\n", n); if (n[1].GetUnsignedConst() >= n[0].GetValueWidth()) FatalError("BVTypeCheck: index is greater or equal to the bitwidth.\n", n); break; case PARAMBOOL: if(2 != n.Degree()) FatalError("BVTypeCheck: PARAMBOOL formula can have exactly two childNodes", n); break; case EQ: if (n.Degree() != 2) FatalError("BVTypeCheck: should have exactly 2 args\n", n); if (!(n[0].GetValueWidth() == n[1].GetValueWidth() && n[0].GetIndexWidth() == n[1].GetIndexWidth())) { cerr << "valuewidth of lhs of EQ: " << n[0].GetValueWidth() << endl; cerr << "valuewidth of rhs of EQ: " << n[1].GetValueWidth() << endl; cerr << "indexwidth of lhs of EQ: " << n[0].GetIndexWidth() << endl; cerr << "indexwidth of rhs of EQ: " << n[1].GetIndexWidth() << endl; FatalError("BVTypeCheck: terms in atomic formulas must be of equal length", n); } break; case BVLT: case BVLE: case BVGT: case BVGE: case BVSLT: case BVSLE: case BVSGT: case BVSGE: if (n.Degree() != 2) FatalError("BVTypeCheck: should have exactly 2 args\n", n); if (BITVECTOR_TYPE != n[0].GetType() && BITVECTOR_TYPE != n[1].GetType()) FatalError("BVTypeCheck: terms in atomic formulas must be bitvectors", n); if (n[0].GetValueWidth() != n[1].GetValueWidth()) FatalError("BVTypeCheck: terms in atomic formulas must be of equal length", n); if (n[0].GetIndexWidth() != n[1].GetIndexWidth()) FatalError("BVTypeCheck: terms in atomic formulas must be of equal length", n); break; case NOT: if (1 != n.Degree()) FatalError("BVTypeCheck: NOT formula can have exactly one childNode", n); break; case AND: case OR: case XOR: case NAND: case NOR: if (2 > n.Degree()) FatalError("BVTypeCheck: AND/OR/XOR/NAND/NOR: must have atleast 2 ChildNodes", n); break; case IFF: case IMPLIES: if (2 != n.Degree()) FatalError("BVTypeCheck:IFF/IMPLIES must have exactly 2 ChildNodes", n); break; case ITE: if (3 != n.Degree()) FatalError("BVTypeCheck:ITE must have exactly 3 ChildNodes", n); break; default: FatalError("BVTypeCheck: Unrecognized kind: "); break; } } return true; } //End of TypeCheck function
ASTNode ArrayTransformer::TransformTerm(const ASTNode& term) { assert(TransformMap != NULL); const Kind k = term.GetKind(); if (!is_Term_kind(k)) FatalError("TransformTerm: Illegal kind: You have input a nonterm:", term, k); ASTNodeMap::const_iterator iter; if ((iter = TransformMap->find(term)) != TransformMap->end()) return iter->second; ASTNode result; switch (k) { case SYMBOL: case BVCONST: { result = term; break; } case WRITE: FatalError("TransformTerm: this kind is not supported", term); break; case READ: result = TransformArrayRead(term); break; case ITE: { ASTNode cond = term[0]; ASTNode thn = term[1]; ASTNode els = term[2]; cond = TransformFormula(cond); if (ASTTrue == cond) result = TransformTerm(thn); else if (ASTFalse == cond) result = TransformTerm(els); else { thn = TransformTerm(thn); els = TransformTerm(els); result = simp->CreateSimplifiedTermITE(cond, thn, els); } assert(result.GetIndexWidth() ==term.GetIndexWidth()); break; } default: { const ASTVec& c = term.GetChildren(); ASTVec::const_iterator it = c.begin(); ASTVec::const_iterator itend = c.end(); const unsigned width = term.GetValueWidth(); const unsigned indexwidth = term.GetIndexWidth(); ASTVec o; o.reserve(c.size()); for (; it != itend; it++) { o.push_back(TransformTerm(*it)); } if (c!=o) { result = nf->CreateArrayTerm(k,indexwidth, width, o); } else result = term; const Kind k = result.GetKind(); if (BVDIV == k || BVMOD == k || SBVDIV == k || SBVREM == k || SBVMOD == k) { // I had this as a reference, but that was wrong. Because // "result" gets over-written in the next block, result[1], may // get a reference count of zero, so be garbage collected. const ASTNode bottom = result[1]; if (SBVDIV == result.GetKind() || SBVREM == result.GetKind() || SBVMOD == result.GetKind()) { result = TranslateSignedDivModRem(result); } if (bm->UserFlags.division_by_zero_returns_one_flag) { // This is a difficult rule to introduce in other // places because it's recursive. i.e. result is // embedded unchanged inside the result. unsigned inputValueWidth = result.GetValueWidth(); ASTNode zero = bm->CreateZeroConst(inputValueWidth); ASTNode one = bm->CreateOneConst(inputValueWidth); result = nf->CreateTerm(ITE, inputValueWidth, nf->CreateNode(EQ, zero, bottom), one, result); //return result; if (bm->UserFlags.optimize_flag) return simp->SimplifyTerm_TopLevel(result); else return result; } } } break; } if (term.Degree() > 0) (*TransformMap)[term] = result; if (term.GetValueWidth() != result.GetValueWidth()) FatalError("TransformTerm: "\ "result and input terms are of different length", result); if (term.GetIndexWidth() != result.GetIndexWidth()) { cerr << "TransformTerm: input term is : " << term << endl; FatalError("TransformTerm: "\ "result & input terms have different index length", result); } return result; } //End of TransformTerm