1 /* 2 * Copyright 2011, The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "StubLayout.h" 18 19 #include "utils/flush_cpu_cache.h" 20 #include "utils/raw_ostream.h" 21 #include "utils/rsl_assert.h" 22 23 #include <stdint.h> 24 #include <stdlib.h> 25 26 StubLayout::StubLayout() : table(NULL), count(0) { 27 } 28 29 void StubLayout::initStubTable(unsigned char *table_, size_t count_) { 30 table = table_; 31 count = count_; 32 } 33 34 void *StubLayout::allocateStub(void *addr) { 35 // Check if we have created this stub or not. 36 std::map<void *, void *>::iterator index_iter = stub_index.find(addr); 37 38 if (index_iter != stub_index.end()) { 39 return index_iter->second; 40 } 41 42 // We have to create a new stub 43 if (count == 0) { 44 // No free stub slot is available 45 return NULL; 46 } 47 48 // Initialize the stub 49 unsigned char *stub = table; 50 setStubAddress(stub, addr); 51 stub_index.insert(std::make_pair(addr, stub)); 52 53 // Increase the free stub slot pointer 54 table += getUnitStubSize(); 55 count--; 56 57 return stub; 58 } 59 60 size_t StubLayout::calcStubTableSize(size_t count) const { 61 return count * getUnitStubSize(); 62 } 63 64 size_t StubLayoutARM::getUnitStubSize() const { 65 return 8; 66 } 67 68 void StubLayoutARM::setStubAddress(void *stub_, void *addr) { 69 uint8_t *stub = (uint8_t *)stub_; 70 stub[0] = 0x04; // ldr pc, [pc, #-4] 71 stub[1] = 0xf0; // ldr pc, [pc, #-4] 72 stub[2] = 0x1f; // ldr pc, [pc, #-4] 73 stub[3] = 0xe5; // ldr pc, [pc, #-4] 74 75 void **target = (void **)(stub + 4); 76 *target = addr; 77 } 78 79 size_t StubLayoutMIPS::getUnitStubSize() const { 80 return 16; 81 } 82 83 void StubLayoutMIPS::setStubAddress(void *stub_, void *addr) { 84 uint32_t addr32 = (uint32_t)(uintptr_t)addr; 85 uint16_t addr_hi16 = (addr32 >> 16) & 0xffff; 86 uint16_t addr_lo16 = addr32 & 0xffff; 87 88 uint32_t *stub = (uint32_t *)stub_; 89 stub[0] = 0x3c190000ul | addr_hi16; // lui 90 stub[1] = 0x37390000ul | addr_lo16; // ori 91 stub[2] = 0x03200008ul; // jr (jump register) 92 stub[3] = 0x00000000ul; // nop 93 } 94
