210 lines · cpp
1//==-- loop_proto_to_llvm.cpp - Protobuf-C++ conversion2//---------------------==//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9//10// Implements functions for converting between protobufs and LLVM IR.11//12//13//===----------------------------------------------------------------------===//14 15#include "loop_proto_to_llvm.h"16#include "cxx_loop_proto.pb.h"17#include "../handle-llvm/input_arrays.h"18 19// The following is needed to convert protos in human-readable form20#include <google/protobuf/text_format.h>21 22#include <ostream>23#include <sstream>24 25namespace clang_fuzzer {26 27// Forward decls28std::string BinopToString(std::ostream &os, const BinaryOp &x);29std::string StateSeqToString(std::ostream &os, const StatementSeq &x);30 31// Counter variable to generate new LLVM IR variable names and wrapper function32static std::string get_var() {33 static int ctr = 0;34 return "%var" + std::to_string(ctr++);35}36 37static bool inner_loop = false;38class InnerLoop {39 public:40 InnerLoop() {41 inner_loop = true;42 }43 ~InnerLoop() {44 inner_loop = false;45 }46};47 48 49// Proto to LLVM.50 51std::string ConstToString(const Const &x) {52 return std::to_string(x.val());53}54std::string VarRefToString(std::ostream &os, const VarRef &x) {55 std::string which_loop = inner_loop ? "inner" : "outer";56 std::string arr;57 switch(x.arr()) {58 case VarRef::ARR_A:59 arr = "%a";60 break;61 case VarRef::ARR_B:62 arr = "%b";63 break;64 case VarRef::ARR_C:65 arr = "%c";66 break;67 }68 std::string ptr_var = get_var();69 os << ptr_var << " = getelementptr inbounds i32, i32* " << arr70 << ", i64 %" << which_loop << "_ct\n";71 return ptr_var;72}73std::string RvalueToString(std::ostream &os, const Rvalue &x) {74 if(x.has_cons())75 return ConstToString(x.cons());76 if(x.has_binop())77 return BinopToString(os, x.binop());78 if(x.has_varref()) {79 std::string var_ref = VarRefToString(os, x.varref());80 std::string val_var = get_var();81 os << val_var << " = load i32, i32* " << var_ref << "\n";82 return val_var;83 }84 return "1";85 86}87std::string BinopToString(std::ostream &os, const BinaryOp &x) {88 std::string left = RvalueToString(os, x.left());89 std::string right = RvalueToString(os, x.right());90 std::string op;91 switch (x.op()) {92 case BinaryOp::PLUS:93 op = "add";94 break;95 case BinaryOp::MINUS:96 op = "sub";97 break;98 case BinaryOp::MUL:99 op = "mul";100 break;101 case BinaryOp::XOR:102 op = "xor";103 break;104 case BinaryOp::AND:105 op = "and";106 break;107 case BinaryOp::OR:108 op = "or";109 break;110 // Support for Boolean operators will be added later111 case BinaryOp::EQ:112 case BinaryOp::NE:113 case BinaryOp::LE:114 case BinaryOp::GE:115 case BinaryOp::LT:116 case BinaryOp::GT:117 op = "add";118 break;119 }120 std::string val_var = get_var();121 os << val_var << " = " << op << " i32 " << left << ", " << right << "\n";122 return val_var;123}124std::ostream &operator<<(std::ostream &os, const AssignmentStatement &x) {125 std::string rvalue = RvalueToString(os, x.rvalue());126 std::string var_ref = VarRefToString(os, x.varref());127 return os << "store i32 " << rvalue << ", i32* " << var_ref << "\n";128}129std::ostream &operator<<(std::ostream &os, const Statement &x) {130 return os << x.assignment();131}132std::ostream &operator<<(std::ostream &os, const StatementSeq &x) {133 for (auto &st : x.statements()) {134 os << st;135 }136 return os;137}138void NestedLoopToString(std::ostream &os, const LoopFunction &x) {139 os << "target triple = \"x86_64-unknown-linux-gnu\"\n"140 << "define void @foo(i32* %a, i32* %b, i32* noalias %c, i64 %s) {\n"141 << "outer_loop_start:\n"142 << "%cmp = icmp sgt i64 %s, 0\n"143 << "br i1 %cmp, label %inner_loop_start, label %end\n"144 << "outer_loop:\n"145 << x.outer_statements()146 << "%o_ct_new = add i64 %outer_ct, 1\n"147 << "%jmp_outer = icmp eq i64 %o_ct_new, %s\n"148 << "br i1 %jmp_outer, label %end, label %inner_loop_start\n"149 << "inner_loop_start:\n"150 << "%outer_ct = phi i64 [%o_ct_new, %outer_loop], [0, %outer_loop_start]\n"151 << "br label %inner_loop\n"152 << "inner_loop:\n"153 << "%inner_ct = phi i64 [0, %inner_loop_start], [%i_ct_new, %inner_loop]\n";154 {155 InnerLoop IL;156 os << x.inner_statements();157 }158 os << "%i_ct_new = add i64 %inner_ct, 1\n"159 << "%jmp_inner = icmp eq i64 %i_ct_new, %s\n"160 << "br i1 %jmp_inner, label %outer_loop, label %inner_loop, !llvm.loop !0\n"161 << "end:\n"162 << "ret void\n"163 << "}\n"164 << "!0 = distinct !{!0, !1, !2}\n"165 << "!1 = !{!\"llvm.loop.vectorize.enable\", i1 true}\n"166 << "!2 = !{!\"llvm.loop.vectorize.width\", i32 " << kArraySize << "}\n";167}168void SingleLoopToString(std::ostream &os, const LoopFunction &x) {169 os << "target triple = \"x86_64-unknown-linux-gnu\"\n"170 << "define void @foo(i32* %a, i32* %b, i32* noalias %c, i64 %s) {\n"171 << "%cmp = icmp sgt i64 %s, 0\n"172 << "br i1 %cmp, label %start, label %end\n"173 << "start:\n"174 << "br label %loop\n"175 << "end:\n"176 << "ret void\n"177 << "loop:\n"178 << "%outer_ct = phi i64 [ %ctnew, %loop ], [ 0, %start ]\n"179 << x.outer_statements()180 << "%ctnew = add i64 %outer_ct, 1\n"181 << "%j = icmp eq i64 %ctnew, %s\n"182 << "br i1 %j, label %end, label %loop, !llvm.loop !0\n}\n"183 << "!0 = distinct !{!0, !1, !2}\n"184 << "!1 = !{!\"llvm.loop.vectorize.enable\", i1 true}\n"185 << "!2 = !{!\"llvm.loop.vectorize.width\", i32 " << kArraySize << "}\n";186}187std::ostream &operator<<(std::ostream &os, const LoopFunction &x) {188 if (x.has_inner_statements())189 NestedLoopToString(os, x);190 else191 SingleLoopToString(os, x);192 return os;193}194 195// ---------------------------------196 197std::string LoopFunctionToLLVMString(const LoopFunction &input) {198 std::ostringstream os;199 os << input;200 return os.str();201}202std::string LoopProtoToLLVM(const uint8_t *data, size_t size) {203 LoopFunction message;204 if (!message.ParsePartialFromArray(data, size))205 return "#error invalid proto\n";206 return LoopFunctionToLLVMString(message);207}208 209} // namespace clang_fuzzer210