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https://github.com/c64scene-ar/llvm-6502.git
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31683 91177308-0d34-0410-b5e6-96231b3b80d8
912 lines
36 KiB
C++
912 lines
36 KiB
C++
//===- Miscompilation.cpp - Debug program miscompilations -----------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file was developed by the LLVM research group and is distributed under
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// the University of Illinois Open Source License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements optimizer and code generation miscompilation debugging
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// support.
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//
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//===----------------------------------------------------------------------===//
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#include "BugDriver.h"
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#include "ListReducer.h"
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#include "llvm/Constants.h"
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#include "llvm/DerivedTypes.h"
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#include "llvm/Instructions.h"
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#include "llvm/Linker.h"
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#include "llvm/Module.h"
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#include "llvm/Pass.h"
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#include "llvm/Analysis/Verifier.h"
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#include "llvm/Support/Mangler.h"
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#include "llvm/Transforms/Utils/Cloning.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/FileUtilities.h"
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#include "llvm/Config/config.h" // for HAVE_LINK_R
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using namespace llvm;
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namespace llvm {
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extern cl::list<std::string> InputArgv;
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}
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namespace {
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static llvm::cl::opt<bool>
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DisableLoopExtraction("disable-loop-extraction",
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cl::desc("Don't extract loops when searching for miscompilations"),
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cl::init(false));
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class ReduceMiscompilingPasses : public ListReducer<const PassInfo*> {
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BugDriver &BD;
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public:
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ReduceMiscompilingPasses(BugDriver &bd) : BD(bd) {}
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virtual TestResult doTest(std::vector<const PassInfo*> &Prefix,
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std::vector<const PassInfo*> &Suffix);
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};
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}
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/// TestResult - After passes have been split into a test group and a control
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/// group, see if they still break the program.
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///
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ReduceMiscompilingPasses::TestResult
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ReduceMiscompilingPasses::doTest(std::vector<const PassInfo*> &Prefix,
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std::vector<const PassInfo*> &Suffix) {
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// First, run the program with just the Suffix passes. If it is still broken
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// with JUST the kept passes, discard the prefix passes.
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std::cout << "Checking to see if '" << getPassesString(Suffix)
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<< "' compile correctly: ";
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std::string BytecodeResult;
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if (BD.runPasses(Suffix, BytecodeResult, false/*delete*/, true/*quiet*/)) {
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std::cerr << " Error running this sequence of passes"
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<< " on the input program!\n";
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BD.setPassesToRun(Suffix);
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BD.EmitProgressBytecode("pass-error", false);
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exit(BD.debugOptimizerCrash());
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}
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// Check to see if the finished program matches the reference output...
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if (BD.diffProgram(BytecodeResult, "", true /*delete bytecode*/)) {
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std::cout << " nope.\n";
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if (Suffix.empty()) {
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std::cerr << BD.getToolName() << ": I'm confused: the test fails when "
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<< "no passes are run, nondeterministic program?\n";
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exit(1);
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}
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return KeepSuffix; // Miscompilation detected!
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}
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std::cout << " yup.\n"; // No miscompilation!
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if (Prefix.empty()) return NoFailure;
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// Next, see if the program is broken if we run the "prefix" passes first,
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// then separately run the "kept" passes.
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std::cout << "Checking to see if '" << getPassesString(Prefix)
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<< "' compile correctly: ";
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// If it is not broken with the kept passes, it's possible that the prefix
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// passes must be run before the kept passes to break it. If the program
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// WORKS after the prefix passes, but then fails if running the prefix AND
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// kept passes, we can update our bytecode file to include the result of the
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// prefix passes, then discard the prefix passes.
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//
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if (BD.runPasses(Prefix, BytecodeResult, false/*delete*/, true/*quiet*/)) {
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std::cerr << " Error running this sequence of passes"
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<< " on the input program!\n";
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BD.setPassesToRun(Prefix);
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BD.EmitProgressBytecode("pass-error", false);
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exit(BD.debugOptimizerCrash());
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}
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// If the prefix maintains the predicate by itself, only keep the prefix!
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if (BD.diffProgram(BytecodeResult)) {
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std::cout << " nope.\n";
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sys::Path(BytecodeResult).eraseFromDisk();
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return KeepPrefix;
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}
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std::cout << " yup.\n"; // No miscompilation!
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// Ok, so now we know that the prefix passes work, try running the suffix
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// passes on the result of the prefix passes.
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//
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Module *PrefixOutput = ParseInputFile(BytecodeResult);
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if (PrefixOutput == 0) {
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std::cerr << BD.getToolName() << ": Error reading bytecode file '"
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<< BytecodeResult << "'!\n";
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exit(1);
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}
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sys::Path(BytecodeResult).eraseFromDisk(); // No longer need the file on disk
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// Don't check if there are no passes in the suffix.
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if (Suffix.empty())
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return NoFailure;
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std::cout << "Checking to see if '" << getPassesString(Suffix)
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<< "' passes compile correctly after the '"
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<< getPassesString(Prefix) << "' passes: ";
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Module *OriginalInput = BD.swapProgramIn(PrefixOutput);
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if (BD.runPasses(Suffix, BytecodeResult, false/*delete*/, true/*quiet*/)) {
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std::cerr << " Error running this sequence of passes"
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<< " on the input program!\n";
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BD.setPassesToRun(Suffix);
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BD.EmitProgressBytecode("pass-error", false);
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exit(BD.debugOptimizerCrash());
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}
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// Run the result...
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if (BD.diffProgram(BytecodeResult, "", true/*delete bytecode*/)) {
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std::cout << " nope.\n";
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delete OriginalInput; // We pruned down the original input...
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return KeepSuffix;
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}
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// Otherwise, we must not be running the bad pass anymore.
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std::cout << " yup.\n"; // No miscompilation!
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delete BD.swapProgramIn(OriginalInput); // Restore orig program & free test
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return NoFailure;
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}
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namespace {
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class ReduceMiscompilingFunctions : public ListReducer<Function*> {
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BugDriver &BD;
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bool (*TestFn)(BugDriver &, Module *, Module *);
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public:
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ReduceMiscompilingFunctions(BugDriver &bd,
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bool (*F)(BugDriver &, Module *, Module *))
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: BD(bd), TestFn(F) {}
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virtual TestResult doTest(std::vector<Function*> &Prefix,
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std::vector<Function*> &Suffix) {
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if (!Suffix.empty() && TestFuncs(Suffix))
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return KeepSuffix;
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if (!Prefix.empty() && TestFuncs(Prefix))
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return KeepPrefix;
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return NoFailure;
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}
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bool TestFuncs(const std::vector<Function*> &Prefix);
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};
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}
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/// TestMergedProgram - Given two modules, link them together and run the
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/// program, checking to see if the program matches the diff. If the diff
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/// matches, return false, otherwise return true. If the DeleteInputs argument
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/// is set to true then this function deletes both input modules before it
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/// returns.
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///
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static bool TestMergedProgram(BugDriver &BD, Module *M1, Module *M2,
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bool DeleteInputs) {
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// Link the two portions of the program back to together.
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std::string ErrorMsg;
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if (!DeleteInputs) {
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M1 = CloneModule(M1);
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M2 = CloneModule(M2);
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}
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if (Linker::LinkModules(M1, M2, &ErrorMsg)) {
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std::cerr << BD.getToolName() << ": Error linking modules together:"
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<< ErrorMsg << '\n';
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exit(1);
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}
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delete M2; // We are done with this module.
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Module *OldProgram = BD.swapProgramIn(M1);
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// Execute the program. If it does not match the expected output, we must
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// return true.
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bool Broken = BD.diffProgram();
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// Delete the linked module & restore the original
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BD.swapProgramIn(OldProgram);
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delete M1;
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return Broken;
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}
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/// TestFuncs - split functions in a Module into two groups: those that are
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/// under consideration for miscompilation vs. those that are not, and test
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/// accordingly. Each group of functions becomes a separate Module.
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///
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bool ReduceMiscompilingFunctions::TestFuncs(const std::vector<Function*>&Funcs){
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// Test to see if the function is misoptimized if we ONLY run it on the
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// functions listed in Funcs.
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std::cout << "Checking to see if the program is misoptimized when "
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<< (Funcs.size()==1 ? "this function is" : "these functions are")
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<< " run through the pass"
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<< (BD.getPassesToRun().size() == 1 ? "" : "es") << ":";
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PrintFunctionList(Funcs);
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std::cout << '\n';
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// Split the module into the two halves of the program we want.
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Module *ToNotOptimize = CloneModule(BD.getProgram());
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Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize, Funcs);
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// Run the predicate, not that the predicate will delete both input modules.
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return TestFn(BD, ToOptimize, ToNotOptimize);
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}
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/// DisambiguateGlobalSymbols - Mangle symbols to guarantee uniqueness by
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/// modifying predominantly internal symbols rather than external ones.
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///
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static void DisambiguateGlobalSymbols(Module *M) {
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// Try not to cause collisions by minimizing chances of renaming an
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// already-external symbol, so take in external globals and functions as-is.
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// The code should work correctly without disambiguation (assuming the same
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// mangler is used by the two code generators), but having symbols with the
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// same name causes warnings to be emitted by the code generator.
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Mangler Mang(*M);
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// Agree with the CBE on symbol naming
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Mang.markCharUnacceptable('.');
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Mang.setPreserveAsmNames(true);
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for (Module::global_iterator I = M->global_begin(), E = M->global_end();
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I != E; ++I)
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I->setName(Mang.getValueName(I));
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for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
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I->setName(Mang.getValueName(I));
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}
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/// ExtractLoops - Given a reduced list of functions that still exposed the bug,
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/// check to see if we can extract the loops in the region without obscuring the
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/// bug. If so, it reduces the amount of code identified.
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///
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static bool ExtractLoops(BugDriver &BD,
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bool (*TestFn)(BugDriver &, Module *, Module *),
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std::vector<Function*> &MiscompiledFunctions) {
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bool MadeChange = false;
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while (1) {
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if (BugpointIsInterrupted) return MadeChange;
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Module *ToNotOptimize = CloneModule(BD.getProgram());
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Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize,
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MiscompiledFunctions);
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Module *ToOptimizeLoopExtracted = BD.ExtractLoop(ToOptimize);
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if (!ToOptimizeLoopExtracted) {
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// If the loop extractor crashed or if there were no extractible loops,
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// then this chapter of our odyssey is over with.
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delete ToNotOptimize;
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delete ToOptimize;
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return MadeChange;
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}
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std::cerr << "Extracted a loop from the breaking portion of the program.\n";
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// Bugpoint is intentionally not very trusting of LLVM transformations. In
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// particular, we're not going to assume that the loop extractor works, so
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// we're going to test the newly loop extracted program to make sure nothing
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// has broken. If something broke, then we'll inform the user and stop
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// extraction.
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AbstractInterpreter *AI = BD.switchToCBE();
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if (TestMergedProgram(BD, ToOptimizeLoopExtracted, ToNotOptimize, false)) {
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BD.switchToInterpreter(AI);
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// Merged program doesn't work anymore!
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std::cerr << " *** ERROR: Loop extraction broke the program. :("
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<< " Please report a bug!\n";
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std::cerr << " Continuing on with un-loop-extracted version.\n";
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BD.writeProgramToFile("bugpoint-loop-extract-fail-tno.bc", ToNotOptimize);
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BD.writeProgramToFile("bugpoint-loop-extract-fail-to.bc", ToOptimize);
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BD.writeProgramToFile("bugpoint-loop-extract-fail-to-le.bc",
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ToOptimizeLoopExtracted);
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std::cerr << "Please submit the bugpoint-loop-extract-fail-*.bc files.\n";
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delete ToOptimize;
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delete ToNotOptimize;
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delete ToOptimizeLoopExtracted;
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return MadeChange;
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}
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delete ToOptimize;
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BD.switchToInterpreter(AI);
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std::cout << " Testing after loop extraction:\n";
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// Clone modules, the tester function will free them.
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Module *TOLEBackup = CloneModule(ToOptimizeLoopExtracted);
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Module *TNOBackup = CloneModule(ToNotOptimize);
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if (!TestFn(BD, ToOptimizeLoopExtracted, ToNotOptimize)) {
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std::cout << "*** Loop extraction masked the problem. Undoing.\n";
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// If the program is not still broken, then loop extraction did something
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// that masked the error. Stop loop extraction now.
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delete TOLEBackup;
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delete TNOBackup;
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return MadeChange;
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}
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ToOptimizeLoopExtracted = TOLEBackup;
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ToNotOptimize = TNOBackup;
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std::cout << "*** Loop extraction successful!\n";
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std::vector<std::pair<std::string, const FunctionType*> > MisCompFunctions;
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for (Module::iterator I = ToOptimizeLoopExtracted->begin(),
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E = ToOptimizeLoopExtracted->end(); I != E; ++I)
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if (!I->isExternal())
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MisCompFunctions.push_back(std::make_pair(I->getName(),
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I->getFunctionType()));
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// Okay, great! Now we know that we extracted a loop and that loop
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// extraction both didn't break the program, and didn't mask the problem.
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// Replace the current program with the loop extracted version, and try to
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// extract another loop.
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std::string ErrorMsg;
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if (Linker::LinkModules(ToNotOptimize, ToOptimizeLoopExtracted, &ErrorMsg)){
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std::cerr << BD.getToolName() << ": Error linking modules together:"
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<< ErrorMsg << '\n';
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exit(1);
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}
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delete ToOptimizeLoopExtracted;
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// All of the Function*'s in the MiscompiledFunctions list are in the old
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// module. Update this list to include all of the functions in the
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// optimized and loop extracted module.
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MiscompiledFunctions.clear();
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for (unsigned i = 0, e = MisCompFunctions.size(); i != e; ++i) {
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Function *NewF = ToNotOptimize->getFunction(MisCompFunctions[i].first,
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MisCompFunctions[i].second);
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assert(NewF && "Function not found??");
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MiscompiledFunctions.push_back(NewF);
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}
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BD.setNewProgram(ToNotOptimize);
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MadeChange = true;
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}
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}
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namespace {
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class ReduceMiscompiledBlocks : public ListReducer<BasicBlock*> {
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BugDriver &BD;
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bool (*TestFn)(BugDriver &, Module *, Module *);
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std::vector<Function*> FunctionsBeingTested;
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public:
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ReduceMiscompiledBlocks(BugDriver &bd,
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bool (*F)(BugDriver &, Module *, Module *),
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const std::vector<Function*> &Fns)
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: BD(bd), TestFn(F), FunctionsBeingTested(Fns) {}
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virtual TestResult doTest(std::vector<BasicBlock*> &Prefix,
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std::vector<BasicBlock*> &Suffix) {
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if (!Suffix.empty() && TestFuncs(Suffix))
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return KeepSuffix;
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if (TestFuncs(Prefix))
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return KeepPrefix;
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return NoFailure;
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}
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bool TestFuncs(const std::vector<BasicBlock*> &Prefix);
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};
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}
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/// TestFuncs - Extract all blocks for the miscompiled functions except for the
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/// specified blocks. If the problem still exists, return true.
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///
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bool ReduceMiscompiledBlocks::TestFuncs(const std::vector<BasicBlock*> &BBs) {
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// Test to see if the function is misoptimized if we ONLY run it on the
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// functions listed in Funcs.
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std::cout << "Checking to see if the program is misoptimized when all ";
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if (!BBs.empty()) {
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std::cout << "but these " << BBs.size() << " blocks are extracted: ";
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for (unsigned i = 0, e = BBs.size() < 10 ? BBs.size() : 10; i != e; ++i)
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std::cout << BBs[i]->getName() << " ";
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if (BBs.size() > 10) std::cout << "...";
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} else {
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std::cout << "blocks are extracted.";
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}
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std::cout << '\n';
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// Split the module into the two halves of the program we want.
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Module *ToNotOptimize = CloneModule(BD.getProgram());
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Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize,
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FunctionsBeingTested);
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// Try the extraction. If it doesn't work, then the block extractor crashed
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// or something, in which case bugpoint can't chase down this possibility.
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if (Module *New = BD.ExtractMappedBlocksFromModule(BBs, ToOptimize)) {
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delete ToOptimize;
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// Run the predicate, not that the predicate will delete both input modules.
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return TestFn(BD, New, ToNotOptimize);
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}
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delete ToOptimize;
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delete ToNotOptimize;
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return false;
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}
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/// ExtractBlocks - Given a reduced list of functions that still expose the bug,
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/// extract as many basic blocks from the region as possible without obscuring
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/// the bug.
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///
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static bool ExtractBlocks(BugDriver &BD,
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bool (*TestFn)(BugDriver &, Module *, Module *),
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std::vector<Function*> &MiscompiledFunctions) {
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if (BugpointIsInterrupted) return false;
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std::vector<BasicBlock*> Blocks;
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for (unsigned i = 0, e = MiscompiledFunctions.size(); i != e; ++i)
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for (Function::iterator I = MiscompiledFunctions[i]->begin(),
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E = MiscompiledFunctions[i]->end(); I != E; ++I)
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Blocks.push_back(I);
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// Use the list reducer to identify blocks that can be extracted without
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// obscuring the bug. The Blocks list will end up containing blocks that must
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// be retained from the original program.
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unsigned OldSize = Blocks.size();
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// Check to see if all blocks are extractible first.
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if (ReduceMiscompiledBlocks(BD, TestFn,
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MiscompiledFunctions).TestFuncs(std::vector<BasicBlock*>())) {
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Blocks.clear();
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} else {
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ReduceMiscompiledBlocks(BD, TestFn,MiscompiledFunctions).reduceList(Blocks);
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if (Blocks.size() == OldSize)
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return false;
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}
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Module *ProgClone = CloneModule(BD.getProgram());
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Module *ToExtract = SplitFunctionsOutOfModule(ProgClone,
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MiscompiledFunctions);
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Module *Extracted = BD.ExtractMappedBlocksFromModule(Blocks, ToExtract);
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if (Extracted == 0) {
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// Weird, extraction should have worked.
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std::cerr << "Nondeterministic problem extracting blocks??\n";
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delete ProgClone;
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delete ToExtract;
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return false;
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}
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// Otherwise, block extraction succeeded. Link the two program fragments back
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// together.
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delete ToExtract;
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std::vector<std::pair<std::string, const FunctionType*> > MisCompFunctions;
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for (Module::iterator I = Extracted->begin(), E = Extracted->end();
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I != E; ++I)
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if (!I->isExternal())
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MisCompFunctions.push_back(std::make_pair(I->getName(),
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I->getFunctionType()));
|
|
|
|
std::string ErrorMsg;
|
|
if (Linker::LinkModules(ProgClone, Extracted, &ErrorMsg)) {
|
|
std::cerr << BD.getToolName() << ": Error linking modules together:"
|
|
<< ErrorMsg << '\n';
|
|
exit(1);
|
|
}
|
|
delete Extracted;
|
|
|
|
// Set the new program and delete the old one.
|
|
BD.setNewProgram(ProgClone);
|
|
|
|
// Update the list of miscompiled functions.
|
|
MiscompiledFunctions.clear();
|
|
|
|
for (unsigned i = 0, e = MisCompFunctions.size(); i != e; ++i) {
|
|
Function *NewF = ProgClone->getFunction(MisCompFunctions[i].first,
|
|
MisCompFunctions[i].second);
|
|
assert(NewF && "Function not found??");
|
|
MiscompiledFunctions.push_back(NewF);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/// DebugAMiscompilation - This is a generic driver to narrow down
|
|
/// miscompilations, either in an optimization or a code generator.
|
|
///
|
|
static std::vector<Function*>
|
|
DebugAMiscompilation(BugDriver &BD,
|
|
bool (*TestFn)(BugDriver &, Module *, Module *)) {
|
|
// Okay, now that we have reduced the list of passes which are causing the
|
|
// failure, see if we can pin down which functions are being
|
|
// miscompiled... first build a list of all of the non-external functions in
|
|
// the program.
|
|
std::vector<Function*> MiscompiledFunctions;
|
|
Module *Prog = BD.getProgram();
|
|
for (Module::iterator I = Prog->begin(), E = Prog->end(); I != E; ++I)
|
|
if (!I->isExternal())
|
|
MiscompiledFunctions.push_back(I);
|
|
|
|
// Do the reduction...
|
|
if (!BugpointIsInterrupted)
|
|
ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions);
|
|
|
|
std::cout << "\n*** The following function"
|
|
<< (MiscompiledFunctions.size() == 1 ? " is" : "s are")
|
|
<< " being miscompiled: ";
|
|
PrintFunctionList(MiscompiledFunctions);
|
|
std::cout << '\n';
|
|
|
|
// See if we can rip any loops out of the miscompiled functions and still
|
|
// trigger the problem.
|
|
|
|
if (!DisableLoopExtraction)
|
|
if (!BugpointIsInterrupted &&
|
|
ExtractLoops(BD, TestFn, MiscompiledFunctions)) {
|
|
// Okay, we extracted some loops and the problem still appears. See if we
|
|
// can eliminate some of the created functions from being candidates.
|
|
|
|
// Loop extraction can introduce functions with the same name (foo_code).
|
|
// Make sure to disambiguate the symbols so that when the program is split
|
|
// apart that we can link it back together again.
|
|
DisambiguateGlobalSymbols(BD.getProgram());
|
|
|
|
// Do the reduction...
|
|
if (!BugpointIsInterrupted)
|
|
ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions);
|
|
|
|
std::cout << "\n*** The following function"
|
|
<< (MiscompiledFunctions.size() == 1 ? " is" : "s are")
|
|
<< " being miscompiled: ";
|
|
PrintFunctionList(MiscompiledFunctions);
|
|
std::cout << '\n';
|
|
}
|
|
|
|
if (!BugpointIsInterrupted &&
|
|
ExtractBlocks(BD, TestFn, MiscompiledFunctions)) {
|
|
// Okay, we extracted some blocks and the problem still appears. See if we
|
|
// can eliminate some of the created functions from being candidates.
|
|
|
|
// Block extraction can introduce functions with the same name (foo_code).
|
|
// Make sure to disambiguate the symbols so that when the program is split
|
|
// apart that we can link it back together again.
|
|
DisambiguateGlobalSymbols(BD.getProgram());
|
|
|
|
// Do the reduction...
|
|
ReduceMiscompilingFunctions(BD, TestFn).reduceList(MiscompiledFunctions);
|
|
|
|
std::cout << "\n*** The following function"
|
|
<< (MiscompiledFunctions.size() == 1 ? " is" : "s are")
|
|
<< " being miscompiled: ";
|
|
PrintFunctionList(MiscompiledFunctions);
|
|
std::cout << '\n';
|
|
}
|
|
|
|
return MiscompiledFunctions;
|
|
}
|
|
|
|
/// TestOptimizer - This is the predicate function used to check to see if the
|
|
/// "Test" portion of the program is misoptimized. If so, return true. In any
|
|
/// case, both module arguments are deleted.
|
|
///
|
|
static bool TestOptimizer(BugDriver &BD, Module *Test, Module *Safe) {
|
|
// Run the optimization passes on ToOptimize, producing a transformed version
|
|
// of the functions being tested.
|
|
std::cout << " Optimizing functions being tested: ";
|
|
Module *Optimized = BD.runPassesOn(Test, BD.getPassesToRun(),
|
|
/*AutoDebugCrashes*/true);
|
|
std::cout << "done.\n";
|
|
delete Test;
|
|
|
|
std::cout << " Checking to see if the merged program executes correctly: ";
|
|
bool Broken = TestMergedProgram(BD, Optimized, Safe, true);
|
|
std::cout << (Broken ? " nope.\n" : " yup.\n");
|
|
return Broken;
|
|
}
|
|
|
|
|
|
/// debugMiscompilation - This method is used when the passes selected are not
|
|
/// crashing, but the generated output is semantically different from the
|
|
/// input.
|
|
///
|
|
bool BugDriver::debugMiscompilation() {
|
|
// Make sure something was miscompiled...
|
|
if (!BugpointIsInterrupted)
|
|
if (!ReduceMiscompilingPasses(*this).reduceList(PassesToRun)) {
|
|
std::cerr << "*** Optimized program matches reference output! No problem"
|
|
<< " detected...\nbugpoint can't help you with your problem!\n";
|
|
return false;
|
|
}
|
|
|
|
std::cout << "\n*** Found miscompiling pass"
|
|
<< (getPassesToRun().size() == 1 ? "" : "es") << ": "
|
|
<< getPassesString(getPassesToRun()) << '\n';
|
|
EmitProgressBytecode("passinput");
|
|
|
|
std::vector<Function*> MiscompiledFunctions =
|
|
DebugAMiscompilation(*this, TestOptimizer);
|
|
|
|
// Output a bunch of bytecode files for the user...
|
|
std::cout << "Outputting reduced bytecode files which expose the problem:\n";
|
|
Module *ToNotOptimize = CloneModule(getProgram());
|
|
Module *ToOptimize = SplitFunctionsOutOfModule(ToNotOptimize,
|
|
MiscompiledFunctions);
|
|
|
|
std::cout << " Non-optimized portion: ";
|
|
ToNotOptimize = swapProgramIn(ToNotOptimize);
|
|
EmitProgressBytecode("tonotoptimize", true);
|
|
setNewProgram(ToNotOptimize); // Delete hacked module.
|
|
|
|
std::cout << " Portion that is input to optimizer: ";
|
|
ToOptimize = swapProgramIn(ToOptimize);
|
|
EmitProgressBytecode("tooptimize");
|
|
setNewProgram(ToOptimize); // Delete hacked module.
|
|
|
|
return false;
|
|
}
|
|
|
|
/// CleanupAndPrepareModules - Get the specified modules ready for code
|
|
/// generator testing.
|
|
///
|
|
static void CleanupAndPrepareModules(BugDriver &BD, Module *&Test,
|
|
Module *Safe) {
|
|
// Clean up the modules, removing extra cruft that we don't need anymore...
|
|
Test = BD.performFinalCleanups(Test);
|
|
|
|
// If we are executing the JIT, we have several nasty issues to take care of.
|
|
if (!BD.isExecutingJIT()) return;
|
|
|
|
// First, if the main function is in the Safe module, we must add a stub to
|
|
// the Test module to call into it. Thus, we create a new function `main'
|
|
// which just calls the old one.
|
|
if (Function *oldMain = Safe->getNamedFunction("main"))
|
|
if (!oldMain->isExternal()) {
|
|
// Rename it
|
|
oldMain->setName("llvm_bugpoint_old_main");
|
|
// Create a NEW `main' function with same type in the test module.
|
|
Function *newMain = new Function(oldMain->getFunctionType(),
|
|
GlobalValue::ExternalLinkage,
|
|
"main", Test);
|
|
// Create an `oldmain' prototype in the test module, which will
|
|
// corresponds to the real main function in the same module.
|
|
Function *oldMainProto = new Function(oldMain->getFunctionType(),
|
|
GlobalValue::ExternalLinkage,
|
|
oldMain->getName(), Test);
|
|
// Set up and remember the argument list for the main function.
|
|
std::vector<Value*> args;
|
|
for (Function::arg_iterator
|
|
I = newMain->arg_begin(), E = newMain->arg_end(),
|
|
OI = oldMain->arg_begin(); I != E; ++I, ++OI) {
|
|
I->setName(OI->getName()); // Copy argument names from oldMain
|
|
args.push_back(I);
|
|
}
|
|
|
|
// Call the old main function and return its result
|
|
BasicBlock *BB = new BasicBlock("entry", newMain);
|
|
CallInst *call = new CallInst(oldMainProto, args, "", BB);
|
|
|
|
// If the type of old function wasn't void, return value of call
|
|
new ReturnInst(call, BB);
|
|
}
|
|
|
|
// The second nasty issue we must deal with in the JIT is that the Safe
|
|
// module cannot directly reference any functions defined in the test
|
|
// module. Instead, we use a JIT API call to dynamically resolve the
|
|
// symbol.
|
|
|
|
// Add the resolver to the Safe module.
|
|
// Prototype: void *getPointerToNamedFunction(const char* Name)
|
|
Function *resolverFunc =
|
|
Safe->getOrInsertFunction("getPointerToNamedFunction",
|
|
PointerType::get(Type::SByteTy),
|
|
PointerType::get(Type::SByteTy), (Type *)0);
|
|
|
|
// Use the function we just added to get addresses of functions we need.
|
|
for (Module::iterator F = Safe->begin(), E = Safe->end(); F != E; ++F) {
|
|
if (F->isExternal() && !F->use_empty() && &*F != resolverFunc &&
|
|
F->getIntrinsicID() == 0 /* ignore intrinsics */) {
|
|
Function *TestFn = Test->getNamedFunction(F->getName());
|
|
|
|
// Don't forward functions which are external in the test module too.
|
|
if (TestFn && !TestFn->isExternal()) {
|
|
// 1. Add a string constant with its name to the global file
|
|
Constant *InitArray = ConstantArray::get(F->getName());
|
|
GlobalVariable *funcName =
|
|
new GlobalVariable(InitArray->getType(), true /*isConstant*/,
|
|
GlobalValue::InternalLinkage, InitArray,
|
|
F->getName() + "_name", Safe);
|
|
|
|
// 2. Use `GetElementPtr *funcName, 0, 0' to convert the string to an
|
|
// sbyte* so it matches the signature of the resolver function.
|
|
|
|
// GetElementPtr *funcName, ulong 0, ulong 0
|
|
std::vector<Constant*> GEPargs(2,Constant::getNullValue(Type::IntTy));
|
|
Value *GEP =
|
|
ConstantExpr::getGetElementPtr(funcName, GEPargs);
|
|
std::vector<Value*> ResolverArgs;
|
|
ResolverArgs.push_back(GEP);
|
|
|
|
// Rewrite uses of F in global initializers, etc. to uses of a wrapper
|
|
// function that dynamically resolves the calls to F via our JIT API
|
|
if (!F->use_empty()) {
|
|
// Create a new global to hold the cached function pointer.
|
|
Constant *NullPtr = ConstantPointerNull::get(F->getType());
|
|
GlobalVariable *Cache =
|
|
new GlobalVariable(F->getType(), false,GlobalValue::InternalLinkage,
|
|
NullPtr,F->getName()+".fpcache", F->getParent());
|
|
|
|
// Construct a new stub function that will re-route calls to F
|
|
const FunctionType *FuncTy = F->getFunctionType();
|
|
Function *FuncWrapper = new Function(FuncTy,
|
|
GlobalValue::InternalLinkage,
|
|
F->getName() + "_wrapper",
|
|
F->getParent());
|
|
BasicBlock *EntryBB = new BasicBlock("entry", FuncWrapper);
|
|
BasicBlock *DoCallBB = new BasicBlock("usecache", FuncWrapper);
|
|
BasicBlock *LookupBB = new BasicBlock("lookupfp", FuncWrapper);
|
|
|
|
// Check to see if we already looked up the value.
|
|
Value *CachedVal = new LoadInst(Cache, "fpcache", EntryBB);
|
|
Value *IsNull = new SetCondInst(Instruction::SetEQ, CachedVal,
|
|
NullPtr, "isNull", EntryBB);
|
|
new BranchInst(LookupBB, DoCallBB, IsNull, EntryBB);
|
|
|
|
// Resolve the call to function F via the JIT API:
|
|
//
|
|
// call resolver(GetElementPtr...)
|
|
CallInst *Resolver = new CallInst(resolverFunc, ResolverArgs,
|
|
"resolver", LookupBB);
|
|
// cast the result from the resolver to correctly-typed function
|
|
CastInst *CastedResolver =
|
|
new CastInst(Resolver, PointerType::get(F->getFunctionType()),
|
|
"resolverCast", LookupBB);
|
|
// Save the value in our cache.
|
|
new StoreInst(CastedResolver, Cache, LookupBB);
|
|
new BranchInst(DoCallBB, LookupBB);
|
|
|
|
PHINode *FuncPtr = new PHINode(NullPtr->getType(), "fp", DoCallBB);
|
|
FuncPtr->addIncoming(CastedResolver, LookupBB);
|
|
FuncPtr->addIncoming(CachedVal, EntryBB);
|
|
|
|
// Save the argument list.
|
|
std::vector<Value*> Args;
|
|
for (Function::arg_iterator i = FuncWrapper->arg_begin(),
|
|
e = FuncWrapper->arg_end(); i != e; ++i)
|
|
Args.push_back(i);
|
|
|
|
// Pass on the arguments to the real function, return its result
|
|
if (F->getReturnType() == Type::VoidTy) {
|
|
new CallInst(FuncPtr, Args, "", DoCallBB);
|
|
new ReturnInst(DoCallBB);
|
|
} else {
|
|
CallInst *Call = new CallInst(FuncPtr, Args, "retval", DoCallBB);
|
|
new ReturnInst(Call, DoCallBB);
|
|
}
|
|
|
|
// Use the wrapper function instead of the old function
|
|
F->replaceAllUsesWith(FuncWrapper);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (verifyModule(*Test) || verifyModule(*Safe)) {
|
|
std::cerr << "Bugpoint has a bug, which corrupted a module!!\n";
|
|
abort();
|
|
}
|
|
}
|
|
|
|
|
|
|
|
/// TestCodeGenerator - This is the predicate function used to check to see if
|
|
/// the "Test" portion of the program is miscompiled by the code generator under
|
|
/// test. If so, return true. In any case, both module arguments are deleted.
|
|
///
|
|
static bool TestCodeGenerator(BugDriver &BD, Module *Test, Module *Safe) {
|
|
CleanupAndPrepareModules(BD, Test, Safe);
|
|
|
|
sys::Path TestModuleBC("bugpoint.test.bc");
|
|
std::string ErrMsg;
|
|
if (TestModuleBC.makeUnique(true, &ErrMsg)) {
|
|
std::cerr << BD.getToolName() << "Error making unique filename: "
|
|
<< ErrMsg << "\n";
|
|
exit(1);
|
|
}
|
|
if (BD.writeProgramToFile(TestModuleBC.toString(), Test)) {
|
|
std::cerr << "Error writing bytecode to `" << TestModuleBC << "'\nExiting.";
|
|
exit(1);
|
|
}
|
|
delete Test;
|
|
|
|
// Make the shared library
|
|
sys::Path SafeModuleBC("bugpoint.safe.bc");
|
|
if (SafeModuleBC.makeUnique(true, &ErrMsg)) {
|
|
std::cerr << BD.getToolName() << "Error making unique filename: "
|
|
<< ErrMsg << "\n";
|
|
exit(1);
|
|
}
|
|
|
|
if (BD.writeProgramToFile(SafeModuleBC.toString(), Safe)) {
|
|
std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting.";
|
|
exit(1);
|
|
}
|
|
std::string SharedObject = BD.compileSharedObject(SafeModuleBC.toString());
|
|
delete Safe;
|
|
|
|
// Run the code generator on the `Test' code, loading the shared library.
|
|
// The function returns whether or not the new output differs from reference.
|
|
int Result = BD.diffProgram(TestModuleBC.toString(), SharedObject, false);
|
|
|
|
if (Result)
|
|
std::cerr << ": still failing!\n";
|
|
else
|
|
std::cerr << ": didn't fail.\n";
|
|
TestModuleBC.eraseFromDisk();
|
|
SafeModuleBC.eraseFromDisk();
|
|
sys::Path(SharedObject).eraseFromDisk();
|
|
|
|
return Result;
|
|
}
|
|
|
|
|
|
/// debugCodeGenerator - debug errors in LLC, LLI, or CBE.
|
|
///
|
|
bool BugDriver::debugCodeGenerator() {
|
|
if ((void*)cbe == (void*)Interpreter) {
|
|
std::string Result = executeProgramWithCBE("bugpoint.cbe.out");
|
|
std::cout << "\n*** The C backend cannot match the reference diff, but it "
|
|
<< "is used as the 'known good'\n code generator, so I can't"
|
|
<< " debug it. Perhaps you have a front-end problem?\n As a"
|
|
<< " sanity check, I left the result of executing the program "
|
|
<< "with the C backend\n in this file for you: '"
|
|
<< Result << "'.\n";
|
|
return true;
|
|
}
|
|
|
|
DisambiguateGlobalSymbols(Program);
|
|
|
|
std::vector<Function*> Funcs = DebugAMiscompilation(*this, TestCodeGenerator);
|
|
|
|
// Split the module into the two halves of the program we want.
|
|
Module *ToNotCodeGen = CloneModule(getProgram());
|
|
Module *ToCodeGen = SplitFunctionsOutOfModule(ToNotCodeGen, Funcs);
|
|
|
|
// Condition the modules
|
|
CleanupAndPrepareModules(*this, ToCodeGen, ToNotCodeGen);
|
|
|
|
sys::Path TestModuleBC("bugpoint.test.bc");
|
|
std::string ErrMsg;
|
|
if (TestModuleBC.makeUnique(true, &ErrMsg)) {
|
|
std::cerr << getToolName() << "Error making unique filename: "
|
|
<< ErrMsg << "\n";
|
|
exit(1);
|
|
}
|
|
|
|
if (writeProgramToFile(TestModuleBC.toString(), ToCodeGen)) {
|
|
std::cerr << "Error writing bytecode to `" << TestModuleBC << "'\nExiting.";
|
|
exit(1);
|
|
}
|
|
delete ToCodeGen;
|
|
|
|
// Make the shared library
|
|
sys::Path SafeModuleBC("bugpoint.safe.bc");
|
|
if (SafeModuleBC.makeUnique(true, &ErrMsg)) {
|
|
std::cerr << getToolName() << "Error making unique filename: "
|
|
<< ErrMsg << "\n";
|
|
exit(1);
|
|
}
|
|
|
|
if (writeProgramToFile(SafeModuleBC.toString(), ToNotCodeGen)) {
|
|
std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting.";
|
|
exit(1);
|
|
}
|
|
std::string SharedObject = compileSharedObject(SafeModuleBC.toString());
|
|
delete ToNotCodeGen;
|
|
|
|
std::cout << "You can reproduce the problem with the command line: \n";
|
|
if (isExecutingJIT()) {
|
|
std::cout << " lli -load " << SharedObject << " " << TestModuleBC;
|
|
} else {
|
|
std::cout << " llc -f " << TestModuleBC << " -o " << TestModuleBC<< ".s\n";
|
|
std::cout << " gcc " << SharedObject << " " << TestModuleBC
|
|
<< ".s -o " << TestModuleBC << ".exe";
|
|
#if defined (HAVE_LINK_R)
|
|
std::cout << " -Wl,-R.";
|
|
#endif
|
|
std::cout << "\n";
|
|
std::cout << " " << TestModuleBC << ".exe";
|
|
}
|
|
for (unsigned i=0, e = InputArgv.size(); i != e; ++i)
|
|
std::cout << " " << InputArgv[i];
|
|
std::cout << '\n';
|
|
std::cout << "The shared object was created with:\n llc -march=c "
|
|
<< SafeModuleBC << " -o temporary.c\n"
|
|
<< " gcc -xc temporary.c -O2 -o " << SharedObject
|
|
#if defined(sparc) || defined(__sparc__) || defined(__sparcv9)
|
|
<< " -G" // Compile a shared library, `-G' for Sparc
|
|
#else
|
|
<< " -shared" // `-shared' for Linux/X86, maybe others
|
|
#endif
|
|
<< " -fno-strict-aliasing\n";
|
|
|
|
return false;
|
|
}
|