1 -- Copyright 2011 the V8 project authors. All rights reserved. 2 -- Redistribution and use in source and binary forms, with or without 3 -- modification, are permitted provided that the following conditions are 4 -- met: 5 -- 6 -- * Redistributions of source code must retain the above copyright 7 -- notice, this list of conditions and the following disclaimer. 8 -- * Redistributions in binary form must reproduce the above 9 -- copyright notice, this list of conditions and the following 10 -- disclaimer in the documentation and/or other materials provided 11 -- with the distribution. 12 -- * Neither the name of Google Inc. nor the names of its 13 -- contributors may be used to endorse or promote products derived 14 -- from this software without specific prior written permission. 15 -- 16 -- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 -- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 -- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 -- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 -- OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 -- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 -- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 -- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 -- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 -- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 -- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 -- This is main driver for gcmole tool. See README for more details. 29 -- Usage: CLANG_BIN=clang-bin-dir lua tools/gcmole/gcmole.lua [arm|ia32|x64] 30 31 local DIR = arg[0]:match("^(.+)/[^/]+$") 32 33 local FLAGS = { 34 -- Do not build gcsuspects file and reuse previously generated one. 35 reuse_gcsuspects = false; 36 37 -- Print commands to console before executing them. 38 verbose = false; 39 40 -- Perform dead variable analysis (generates many false positives). 41 -- TODO add some sort of whiteliste to filter out false positives. 42 dead_vars = false; 43 44 -- When building gcsuspects whitelist certain functions as if they 45 -- can be causing GC. Currently used to reduce number of false 46 -- positives in dead variables analysis. See TODO for WHITELIST 47 -- below. 48 whitelist = true; 49 } 50 local ARGS = {} 51 52 for i = 1, #arg do 53 local flag = arg[i]:match "^%-%-([%w_-]+)$" 54 if flag then 55 local no, real_flag = flag:match "^(no)([%w_-]+)$" 56 if real_flag then flag = real_flag end 57 58 flag = flag:gsub("%-", "_") 59 if FLAGS[flag] ~= nil then 60 FLAGS[flag] = (no ~= "no") 61 else 62 error("Unknown flag: " .. flag) 63 end 64 else 65 table.insert(ARGS, arg[i]) 66 end 67 end 68 69 local ARCHS = ARGS[1] and { ARGS[1] } or { 'ia32', 'arm', 'x64' } 70 71 local io = require "io" 72 local os = require "os" 73 74 function log(...) 75 io.stderr:write(string.format(...)) 76 io.stderr:write "\n" 77 end 78 79 ------------------------------------------------------------------------------- 80 -- Clang invocation 81 82 local CLANG_BIN = os.getenv "CLANG_BIN" 83 84 if not CLANG_BIN or CLANG_BIN == "" then 85 error "CLANG_BIN not set" 86 end 87 88 local function MakeClangCommandLine(plugin, plugin_args, triple, arch_define) 89 if plugin_args then 90 for i = 1, #plugin_args do 91 plugin_args[i] = "-plugin-arg-" .. plugin .. " " .. plugin_args[i] 92 end 93 plugin_args = " " .. table.concat(plugin_args, " ") 94 end 95 return CLANG_BIN .. "/clang -cc1 -load " .. DIR .. "/libgcmole.so" 96 .. " -plugin " .. plugin 97 .. (plugin_args or "") 98 .. " -triple " .. triple 99 .. " -D" .. arch_define 100 .. " -DENABLE_DEBUGGER_SUPPORT" 101 .. " -Isrc" 102 end 103 104 function InvokeClangPluginForEachFile(filenames, cfg, func) 105 local cmd_line = MakeClangCommandLine(cfg.plugin, 106 cfg.plugin_args, 107 cfg.triple, 108 cfg.arch_define) 109 for _, filename in ipairs(filenames) do 110 log("-- %s", filename) 111 local action = cmd_line .. " src/" .. filename .. " 2>&1" 112 if FLAGS.verbose then print('popen ', action) end 113 local pipe = io.popen(action) 114 func(filename, pipe:lines()) 115 pipe:close() 116 end 117 end 118 119 ------------------------------------------------------------------------------- 120 -- SConscript parsing 121 122 local function ParseSConscript() 123 local f = assert(io.open("src/SConscript"), "failed to open SConscript") 124 local sconscript = f:read('*a') 125 f:close() 126 127 local SOURCES = sconscript:match "SOURCES = {(.-)}"; 128 129 local sources = {} 130 131 for condition, list in 132 SOURCES:gmatch "'([^']-)': Split%(\"\"\"(.-)\"\"\"%)" do 133 local files = {} 134 for file in list:gmatch "[^%s]+" do table.insert(files, file) end 135 sources[condition] = files 136 end 137 138 for condition, list in SOURCES:gmatch "'([^']-)': %[(.-)%]" do 139 local files = {} 140 for file in list:gmatch "'([^']-)'" do table.insert(files, file) end 141 sources[condition] = files 142 end 143 144 return sources 145 end 146 147 local function EvaluateCondition(cond, props) 148 if cond == 'all' then return true end 149 150 local p, v = cond:match "(%w+):(%w+)" 151 152 assert(p and v, "failed to parse condition: " .. cond) 153 assert(props[p] ~= nil, "undefined configuration property: " .. p) 154 155 return props[p] == v 156 end 157 158 local function BuildFileList(sources, props) 159 local list = {} 160 for condition, files in pairs(sources) do 161 if EvaluateCondition(condition, props) then 162 for i = 1, #files do table.insert(list, files[i]) end 163 end 164 end 165 return list 166 end 167 168 local sources = ParseSConscript() 169 170 local function FilesForArch(arch) 171 return BuildFileList(sources, { os = 'linux', 172 arch = arch, 173 mode = 'debug', 174 simulator = ''}) 175 end 176 177 local mtConfig = {} 178 179 mtConfig.__index = mtConfig 180 181 local function config (t) return setmetatable(t, mtConfig) end 182 183 function mtConfig:extend(t) 184 local e = {} 185 for k, v in pairs(self) do e[k] = v end 186 for k, v in pairs(t) do e[k] = v end 187 return config(e) 188 end 189 190 local ARCHITECTURES = { 191 ia32 = config { triple = "i586-unknown-linux", 192 arch_define = "V8_TARGET_ARCH_IA32" }, 193 arm = config { triple = "i586-unknown-linux", 194 arch_define = "V8_TARGET_ARCH_ARM" }, 195 x64 = config { triple = "x86_64-unknown-linux", 196 arch_define = "V8_TARGET_ARCH_X64" } 197 } 198 199 ------------------------------------------------------------------------------- 200 -- GCSuspects Generation 201 202 local gc, gc_caused, funcs 203 204 local WHITELIST = { 205 -- The following functions call CEntryStub which is always present. 206 "MacroAssembler.*CallExternalReference", 207 "MacroAssembler.*CallRuntime", 208 "CompileCallLoadPropertyWithInterceptor", 209 "CallIC.*GenerateMiss", 210 211 -- DirectCEntryStub is a special stub used on ARM. 212 -- It is pinned and always present. 213 "DirectCEntryStub.*GenerateCall", 214 215 -- TODO GCMole currently is sensitive enough to understand that certain 216 -- functions only cause GC and return Failure simulataneously. 217 -- Callsites of such functions are safe as long as they are properly 218 -- check return value and propagate the Failure to the caller. 219 -- It should be possible to extend GCMole to understand this. 220 "Heap.*AllocateFunctionPrototype", 221 222 -- Ignore all StateTag methods. 223 "StateTag", 224 225 -- Ignore printing of elements transition. 226 "PrintElementsTransition" 227 }; 228 229 local function AddCause(name, cause) 230 local t = gc_caused[name] 231 if not t then 232 t = {} 233 gc_caused[name] = t 234 end 235 table.insert(t, cause) 236 end 237 238 local function resolve(name) 239 local f = funcs[name] 240 241 if not f then 242 f = {} 243 funcs[name] = f 244 245 if name:match "Collect.*Garbage" then 246 gc[name] = true 247 AddCause(name, "<GC>") 248 end 249 250 if FLAGS.whitelist then 251 for i = 1, #WHITELIST do 252 if name:match(WHITELIST[i]) then 253 gc[name] = false 254 end 255 end 256 end 257 end 258 259 return f 260 end 261 262 local function parse (filename, lines) 263 local scope 264 265 for funcname in lines do 266 if funcname:sub(1, 1) ~= '\t' then 267 resolve(funcname) 268 scope = funcname 269 else 270 local name = funcname:sub(2) 271 resolve(name)[scope] = true 272 end 273 end 274 end 275 276 local function propagate () 277 log "** Propagating GC information" 278 279 local function mark(from, callers) 280 for caller, _ in pairs(callers) do 281 if gc[caller] == nil then 282 gc[caller] = true 283 mark(caller, funcs[caller]) 284 end 285 AddCause(caller, from) 286 end 287 end 288 289 for funcname, callers in pairs(funcs) do 290 if gc[funcname] then mark(funcname, callers) end 291 end 292 end 293 294 local function GenerateGCSuspects(arch, files, cfg) 295 -- Reset the global state. 296 gc, gc_caused, funcs = {}, {}, {} 297 298 log ("** Building GC Suspects for %s", arch) 299 InvokeClangPluginForEachFile (files, 300 cfg:extend { plugin = "dump-callees" }, 301 parse) 302 303 propagate() 304 305 local out = assert(io.open("gcsuspects", "w")) 306 for name, value in pairs(gc) do if value then out:write (name, '\n') end end 307 out:close() 308 309 local out = assert(io.open("gccauses", "w")) 310 out:write "GC = {" 311 for name, causes in pairs(gc_caused) do 312 out:write("['", name, "'] = {") 313 for i = 1, #causes do out:write ("'", causes[i], "';") end 314 out:write("};\n") 315 end 316 out:write "}" 317 out:close() 318 319 log ("** GCSuspects generated for %s", arch) 320 end 321 322 -------------------------------------------------------------------------------- 323 -- Analysis 324 325 local function CheckCorrectnessForArch(arch) 326 local files = FilesForArch(arch) 327 local cfg = ARCHITECTURES[arch] 328 329 if not FLAGS.reuse_gcsuspects then 330 GenerateGCSuspects(arch, files, cfg) 331 end 332 333 local processed_files = 0 334 local errors_found = false 335 local function SearchForErrors(filename, lines) 336 processed_files = processed_files + 1 337 for l in lines do 338 errors_found = errors_found or 339 l:match "^[^:]+:%d+:%d+:" or 340 l:match "error" or 341 l:match "warning" 342 print(l) 343 end 344 end 345 346 log("** Searching for evaluation order problems%s for %s", 347 FLAGS.dead_vars and " and dead variables" or "", 348 arch) 349 local plugin_args 350 if FLAGS.dead_vars then plugin_args = { "--dead-vars" } end 351 InvokeClangPluginForEachFile(files, 352 cfg:extend { plugin = "find-problems", 353 plugin_args = plugin_args }, 354 SearchForErrors) 355 log("** Done processing %d files. %s", 356 processed_files, 357 errors_found and "Errors found" or "No errors found") 358 359 return errors_found 360 end 361 362 local function SafeCheckCorrectnessForArch(arch) 363 local status, errors = pcall(CheckCorrectnessForArch, arch) 364 if not status then 365 print(string.format("There was an error: %s", errors)) 366 errors = true 367 end 368 return errors 369 end 370 371 local errors = false 372 373 for _, arch in ipairs(ARCHS) do 374 if not ARCHITECTURES[arch] then 375 error ("Unknown arch: " .. arch) 376 end 377 378 errors = SafeCheckCorrectnessForArch(arch, report) or errors 379 end 380 381 os.exit(errors and 1 or 0) 382
