Compiler.cpp revision b7bce7436876884dfd78ec41d147ddbe47e37cbd 
1/*
2 * Copyright 2010-2012, 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 "bcc/Compiler.h"
18
19#include <llvm/Analysis/Passes.h>
20#include <llvm/CodeGen/RegAllocRegistry.h>
21#include <llvm/IR/Module.h>
22#include <llvm/PassManager.h>
23#include <llvm/Support/TargetRegistry.h>
24#include <llvm/Support/raw_ostream.h>
25#include <llvm/IR/DataLayout.h>
26#include <llvm/Target/TargetMachine.h>
27#include <llvm/Transforms/IPO.h>
28#include <llvm/Transforms/IPO/PassManagerBuilder.h>
29#include <llvm/Transforms/Scalar.h>
30
31#include "bcc/Assert.h"
32#include "bcc/Renderscript/RSExecutable.h"
33#include "bcc/Renderscript/RSScript.h"
34#include "bcc/Renderscript/RSTransforms.h"
35#include "bcc/Script.h"
36#include "bcc/Source.h"
37#include "bcc/Support/CompilerConfig.h"
38#include "bcc/Support/Log.h"
39#include "bcc/Support/OutputFile.h"
40#include "bcinfo/MetadataExtractor.h"
41
42#include <string>
43
44using namespace bcc;
45
46const char *Compiler::GetErrorString(enum ErrorCode pErrCode) {
47  switch (pErrCode) {
48  case kSuccess:
49    return "Successfully compiled.";
50  case kInvalidConfigNoTarget:
51    return "Invalid compiler config supplied (getTarget() returns nullptr.) "
52           "(missing call to CompilerConfig::initialize()?)";
53  case kErrCreateTargetMachine:
54    return "Failed to create llvm::TargetMachine.";
55  case kErrSwitchTargetMachine:
56    return  "Failed to switch llvm::TargetMachine.";
57  case kErrNoTargetMachine:
58    return "Failed to compile the script since there's no available "
59           "TargetMachine. (missing call to Compiler::config()?)";
60  case kErrDataLayoutNoMemory:
61    return "Out of memory when create DataLayout during compilation.";
62  case kErrMaterialization:
63    return "Failed to materialize the module.";
64  case kErrInvalidOutputFileState:
65    return "Supplied output file was invalid (in the error state.)";
66  case kErrPrepareOutput:
67    return "Failed to prepare file for output.";
68  case kPrepareCodeGenPass:
69    return "Failed to construct pass list for code-generation.";
70  case kErrCustomPasses:
71    return "Error occurred while adding custom passes.";
72  case kErrInvalidSource:
73    return "Error loading input bitcode";
74  }
75
76  // This assert should never be reached as the compiler verifies that the
77  // above switch coveres all enum values.
78  assert(false && "Unknown error code encountered");
79  return  "";
80}
81
82//===----------------------------------------------------------------------===//
83// Instance Methods
84//===----------------------------------------------------------------------===//
85Compiler::Compiler() : mTarget(nullptr), mEnableOpt(true) {
86  return;
87}
88
89Compiler::Compiler(const CompilerConfig &pConfig) : mTarget(nullptr),
90                                                    mEnableOpt(true) {
91  const std::string &triple = pConfig.getTriple();
92
93  enum ErrorCode err = config(pConfig);
94  if (err != kSuccess) {
95    ALOGE("%s (%s, features: %s)", GetErrorString(err),
96          triple.c_str(), pConfig.getFeatureString().c_str());
97    return;
98  }
99
100  return;
101}
102
103enum Compiler::ErrorCode Compiler::config(const CompilerConfig &pConfig) {
104  if (pConfig.getTarget() == nullptr) {
105    return kInvalidConfigNoTarget;
106  }
107
108  llvm::TargetMachine *new_target =
109      (pConfig.getTarget())->createTargetMachine(pConfig.getTriple(),
110                                                 pConfig.getCPU(),
111                                                 pConfig.getFeatureString(),
112                                                 pConfig.getTargetOptions(),
113                                                 pConfig.getRelocationModel(),
114                                                 pConfig.getCodeModel(),
115                                                 pConfig.getOptimizationLevel());
116
117  if (new_target == nullptr) {
118    return ((mTarget != nullptr) ? kErrSwitchTargetMachine :
119                                   kErrCreateTargetMachine);
120  }
121
122  // Replace the old TargetMachine.
123  delete mTarget;
124  mTarget = new_target;
125
126  // Adjust register allocation policy according to the optimization level.
127  //  createFastRegisterAllocator: fast but bad quality
128  //  createLinearScanRegisterAllocator: not so fast but good quality
129  if ((pConfig.getOptimizationLevel() == llvm::CodeGenOpt::None)) {
130    llvm::RegisterRegAlloc::setDefault(llvm::createFastRegisterAllocator);
131  } else {
132    llvm::RegisterRegAlloc::setDefault(llvm::createGreedyRegisterAllocator);
133  }
134
135  return kSuccess;
136}
137
138Compiler::~Compiler() {
139  delete mTarget;
140}
141
142enum Compiler::ErrorCode Compiler::runPasses(Script &pScript,
143                                             llvm::raw_ostream &pResult) {
144  // Pass manager for link-time optimization
145  llvm::PassManager passes;
146
147  // Empty MCContext.
148  llvm::MCContext *mc_context = nullptr;
149
150  // Prepare DataLayout target data from Module
151  llvm::DataLayoutPass *data_layout_pass =
152    new (std::nothrow) llvm::DataLayoutPass(*mTarget->getDataLayout());
153
154  if (data_layout_pass == nullptr) {
155    return kErrDataLayoutNoMemory;
156  }
157
158  // Add DataLayout to the pass manager.
159  passes.add(data_layout_pass);
160
161  // Add our custom passes.
162  if (!addCustomPasses(pScript, passes)) {
163    return kErrCustomPasses;
164  }
165
166  if (mTarget->getOptLevel() == llvm::CodeGenOpt::None) {
167    passes.add(llvm::createGlobalOptimizerPass());
168    passes.add(llvm::createConstantMergePass());
169
170  } else {
171    // FIXME: Figure out which passes should be executed.
172    llvm::PassManagerBuilder Builder;
173    Builder.populateLTOPassManager(passes,
174                                   /*Internalize*/ false,
175                                   /*RunInliner*/  true);
176  }
177
178  // Add passes to the pass manager to emit machine code through MC layer.
179  if (mTarget->addPassesToEmitMC(passes, mc_context, pResult,
180                                 /* DisableVerify */false)) {
181    return kPrepareCodeGenPass;
182  }
183
184  // Execute the passes.
185  passes.run(pScript.getSource().getModule());
186
187  return kSuccess;
188}
189
190enum Compiler::ErrorCode Compiler::compile(Script &pScript,
191                                           llvm::raw_ostream &pResult,
192                                           llvm::raw_ostream *IRStream) {
193  llvm::Module &module = pScript.getSource().getModule();
194  enum ErrorCode err;
195
196  if (mTarget == nullptr) {
197    return kErrNoTargetMachine;
198  }
199
200  const std::string &triple = module.getTargetTriple();
201  const llvm::DataLayout *dl = getTargetMachine().getDataLayout();
202  unsigned int pointerSize = dl->getPointerSizeInBits();
203  if (triple == "armv7-none-linux-gnueabi") {
204    if (pointerSize != 32) {
205      return kErrInvalidSource;
206    }
207  } else if (triple == "aarch64-none-linux-gnueabi") {
208    if (pointerSize != 64) {
209      return kErrInvalidSource;
210    }
211  } else {
212    return kErrInvalidSource;
213  }
214
215  // Materialize the bitcode module.
216  if (module.getMaterializer() != nullptr) {
217    // A module with non-null materializer means that it is a lazy-load module.
218    // Materialize it now via invoking MaterializeAllPermanently(). This
219    // function returns false when the materialization is successful.
220    std::error_code ec = module.materializeAllPermanently();
221    if (ec) {
222      ALOGE("Failed to materialize the module `%s'! (%s)",
223            module.getModuleIdentifier().c_str(), ec.message().c_str());
224      return kErrMaterialization;
225    }
226  }
227
228  if ((err = runPasses(pScript, pResult)) != kSuccess) {
229    return err;
230  }
231
232  if (IRStream) {
233    *IRStream << module;
234  }
235
236  return kSuccess;
237}
238
239enum Compiler::ErrorCode Compiler::compile(Script &pScript,
240                                           OutputFile &pResult,
241                                           llvm::raw_ostream *IRStream) {
242  // Check the state of the specified output file.
243  if (pResult.hasError()) {
244    return kErrInvalidOutputFileState;
245  }
246
247  // Open the output file decorated in llvm::raw_ostream.
248  llvm::raw_ostream *out = pResult.dup();
249  if (out == nullptr) {
250    return kErrPrepareOutput;
251  }
252
253  // Delegate the request.
254  enum Compiler::ErrorCode err = compile(pScript, *out, IRStream);
255
256  // Close the output before return.
257  delete out;
258
259  return err;
260}
261
262bool Compiler::addInternalizeSymbolsPass(Script &pScript, llvm::PassManager &pPM) {
263  // Add a pass to internalize the symbols that don't need to have global
264  // visibility.
265  RSScript &script = static_cast<RSScript &>(pScript);
266  llvm::Module &module = script.getSource().getModule();
267  bcinfo::MetadataExtractor me(&module);
268  if (!me.extract()) {
269    bccAssert(false && "Could not extract metadata for module!");
270    return false;
271  }
272
273  // The vector contains the symbols that should not be internalized.
274  std::vector<const char *> export_symbols;
275
276  // Special RS functions should always be global symbols.
277  const char **special_functions = RSExecutable::SpecialFunctionNames;
278  while (*special_functions != nullptr) {
279    export_symbols.push_back(*special_functions);
280    special_functions++;
281  }
282
283  // Visibility of symbols appeared in rs_export_var and rs_export_func should
284  // also be preserved.
285  size_t exportVarCount = me.getExportVarCount();
286  size_t exportFuncCount = me.getExportFuncCount();
287  size_t exportForEachCount = me.getExportForEachSignatureCount();
288  const char **exportVarNameList = me.getExportVarNameList();
289  const char **exportFuncNameList = me.getExportFuncNameList();
290  const char **exportForEachNameList = me.getExportForEachNameList();
291  size_t i;
292
293  for (i = 0; i < exportVarCount; ++i) {
294    export_symbols.push_back(exportVarNameList[i]);
295  }
296
297  for (i = 0; i < exportFuncCount; ++i) {
298    export_symbols.push_back(exportFuncNameList[i]);
299  }
300
301  // Expanded foreach functions should not be internalized, too.
302  // expanded_foreach_funcs keeps the .expand version of the kernel names
303  // around until createInternalizePass() is finished making its own
304  // copy of the visible symbols.
305  std::vector<std::string> expanded_foreach_funcs;
306  for (i = 0; i < exportForEachCount; ++i) {
307    expanded_foreach_funcs.push_back(
308        std::string(exportForEachNameList[i]) + ".expand");
309  }
310
311  for (i = 0; i < exportForEachCount; i++) {
312      export_symbols.push_back(expanded_foreach_funcs[i].c_str());
313  }
314
315  pPM.add(llvm::createInternalizePass(export_symbols));
316
317  return true;
318}
319
320bool Compiler::addInvokeHelperPass(llvm::PassManager &pPM) {
321  llvm::Triple arch(getTargetMachine().getTargetTriple());
322  if (arch.isArch64Bit()) {
323    pPM.add(createRSInvokeHelperPass());
324  }
325  return true;
326}
327
328bool Compiler::addExpandForEachPass(Script &pScript, llvm::PassManager &pPM) {
329  // Script passed to RSCompiler must be a RSScript.
330  RSScript &script = static_cast<RSScript &>(pScript);
331
332  // Expand ForEach on CPU path to reduce launch overhead.
333  bool pEnableStepOpt = true;
334  pPM.add(createRSForEachExpandPass(pEnableStepOpt));
335  if (script.getEmbedInfo())
336    pPM.add(createRSEmbedInfoPass());
337
338  return true;
339}
340
341bool Compiler::addCustomPasses(Script &pScript, llvm::PassManager &pPM) {
342  if (!addInvokeHelperPass(pPM))
343    return false;
344
345  if (!addExpandForEachPass(pScript, pPM))
346    return false;
347
348  if (!addInternalizeSymbolsPass(pScript, pPM))
349    return false;
350
351  return true;
352}
353