1 # Copyright (C) 2010 The Android Open Source Project 2 # 3 # Licensed under the Apache License, Version 2.0 (the "License"); 4 # you may not use this file except in compliance with the License. 5 # You may obtain a copy of the License at 6 # 7 # http://www.apache.org/licenses/LICENSE-2.0 8 # 9 # Unless required by applicable law or agreed to in writing, software 10 # distributed under the License is distributed on an "AS IS" BASIS, 11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 # See the License for the specific language governing permissions and 13 # limitations under the License. 14 15 --------------------------------------------------------------------- 16 Notes on updating the sets of defined opcodes and instruction formats 17 --------------------------------------------------------------------- 18 19 ########## 20 21 If you want to add, delete, or change opcodes: 22 23 * Update the file bytecode.txt, in this directory. 24 25 * Run the regen-all script, in this directory. This will regenerate a 26 number of tables, definitions, and declarations in the code, in 27 dalvik/dx, dalvik/libdex, and libcore/dalvik. 28 29 * Implement/update the opcode in C in vm/mterp/c/... 30 * Verify new code by running with "dalvik.vm.execution-mode = int:portable" 31 or "-Xint:portable". 32 33 * Implement/update the instruction in assembly in vm/mterp/{arm*,x86*}/... 34 * Verify by enabling the assembly (e.g. ARM) handler for that instruction 35 in mterp/config-* and running "int:fast" as above. 36 37 * Implement/update the instruction in 38 vm/compiler/codegen/{arm,x86}/CodegenDriver.c. 39 40 * Rebuild the interpreter code. See the notes in vm/mterp/ReadMe.txt for 41 details. 42 43 * Look in the directory vm/analysis at the files CodeVerify.c, 44 DexVerify.c, and Optimize.c. You may need to update them to account 45 for your changes. 46 * If you change anything here, be sure to try running the system with 47 the verifier enabled (which is in fact the default). 48 49 ########## 50 51 If you want to add, delete, or change instruction formats: 52 53 This is a more manual affair than changing opcodes. 54 55 * Update the file bytecode.txt, and run regen-all, as per above. 56 57 * Update the instruction format list in libdex/InstrUtils.h. 58 59 * Update dexDecodeInstruction() in libdex/InstrUtils.c. 60 61 * Update dumpInstruction() and its helper code in dexdump/DexDump.c. 62 63 * Update the switch inside dvmCompilerMIR2LIR() in 64 vm/compiler/codegen/{arm,x86}/CodegenDriver.c. (There may be other 65 architectures to deal with too.) 66 67 ########## 68 69 Testing your work: 70 71 The Dalvik VM tests (in the vm/tests directory) provide a convenient 72 way to test most of the above without doing any rebuilds. In 73 particular, test 003-omnibus-opcodes will exercise most of the 74 opcodes. 75
