llvm-6502/tools/llvm-diff/llvm-diff.cpp
2010-07-29 18:20:13 +00:00

334 lines
9.3 KiB
C++

//===-- llvm-diff.cpp - Module comparator command-line driver ---*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the command-line driver for the difference engine.
//
//===----------------------------------------------------------------------===//
#include "DifferenceEngine.h"
#include "llvm/Instructions.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/Type.h"
#include "llvm/Assembly/Parser.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/SourceMgr.h"
#include <string>
#include <utility>
using namespace llvm;
/// Reads a module from a file. If the filename ends in .ll, it is
/// interpreted as an assembly file; otherwise, it is interpreted as
/// bitcode. On error, messages are written to stderr and null is
/// returned.
static Module *ReadModule(LLVMContext &Context, StringRef Name) {
// LLVM assembly path.
if (Name.endswith(".ll")) {
SMDiagnostic Diag;
Module *M = ParseAssemblyFile(Name, Diag, Context);
if (M) return M;
Diag.Print("llvmdiff", errs());
return 0;
}
// Bitcode path.
MemoryBuffer *Buffer = MemoryBuffer::getFile(Name);
// ParseBitcodeFile takes ownership of the buffer if it succeeds.
std::string Error;
Module *M = ParseBitcodeFile(Buffer, Context, &Error);
if (M) return M;
errs() << "error parsing " << Name << ": " << Error;
delete Buffer;
return 0;
}
namespace {
struct DiffContext {
DiffContext(Value *L, Value *R)
: L(L), R(R), Differences(false), IsFunction(isa<Function>(L)) {}
Value *L;
Value *R;
bool Differences;
bool IsFunction;
DenseMap<Value*,unsigned> LNumbering;
DenseMap<Value*,unsigned> RNumbering;
};
void ComputeNumbering(Function *F, DenseMap<Value*,unsigned> &Numbering) {
unsigned BBN = 0;
unsigned IN = 0;
// Arguments get the first numbers.
for (Function::arg_iterator
AI = F->arg_begin(), AE = F->arg_end(); AI != AE; ++AI)
if (!AI->hasName())
Numbering[&*AI] = IN++;
// Walk the basic blocks in order.
for (Function::iterator FI = F->begin(), FE = F->end(); FI != FE; ++FI) {
// Basic blocks have their own 'namespace'.
if (!FI->hasName())
Numbering[&*FI] = BBN++;
// Walk the instructions in order.
for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE; ++BI)
// void instructions don't get numbers.
if (!BI->hasName() && !BI->getType()->isVoidTy())
Numbering[&*BI] = IN++;
}
assert(!Numbering.empty() && "asked for numbering but numbering was no-op");
}
class DiffConsumer : public DifferenceEngine::Consumer {
private:
raw_ostream &out;
Module *LModule;
Module *RModule;
SmallVector<DiffContext, 5> contexts;
bool Differences;
unsigned Indent;
void printValue(Value *V, bool isL) {
if (V->hasName()) {
out << (isa<GlobalValue>(V) ? '@' : '%') << V->getName();
return;
}
if (V->getType()->isVoidTy()) {
if (isa<StoreInst>(V)) {
out << "store to ";
printValue(cast<StoreInst>(V)->getPointerOperand(), isL);
} else if (isa<CallInst>(V)) {
out << "call to ";
printValue(cast<CallInst>(V)->getCalledValue(), isL);
} else if (isa<InvokeInst>(V)) {
out << "invoke to ";
printValue(cast<InvokeInst>(V)->getCalledValue(), isL);
} else {
out << *V;
}
return;
}
unsigned N = contexts.size();
while (N > 0) {
--N;
DiffContext &ctxt = contexts[N];
if (!ctxt.IsFunction) continue;
if (isL) {
if (ctxt.LNumbering.empty())
ComputeNumbering(cast<Function>(ctxt.L), ctxt.LNumbering);
out << '%' << ctxt.LNumbering[V];
return;
} else {
if (ctxt.RNumbering.empty())
ComputeNumbering(cast<Function>(ctxt.R), ctxt.RNumbering);
out << '%' << ctxt.RNumbering[V];
return;
}
}
out << "<anonymous>";
}
void header() {
if (contexts.empty()) return;
for (SmallVectorImpl<DiffContext>::iterator
I = contexts.begin(), E = contexts.end(); I != E; ++I) {
if (I->Differences) continue;
if (isa<Function>(I->L)) {
// Extra newline between functions.
if (Differences) out << "\n";
Function *L = cast<Function>(I->L);
Function *R = cast<Function>(I->R);
if (L->getName() != R->getName())
out << "in function " << L->getName()
<< " / " << R->getName() << ":\n";
else
out << "in function " << L->getName() << ":\n";
} else if (isa<BasicBlock>(I->L)) {
BasicBlock *L = cast<BasicBlock>(I->L);
BasicBlock *R = cast<BasicBlock>(I->R);
if (L->hasName() && R->hasName() && L->getName() == R->getName())
out << " in block %" << L->getName() << ":\n";
else {
out << " in block ";
printValue(L, true);
out << " / ";
printValue(R, false);
out << ":\n";
}
} else if (isa<Instruction>(I->L)) {
out << " in instruction ";
printValue(I->L, true);
out << " / ";
printValue(I->R, false);
out << ":\n";
}
I->Differences = true;
}
}
void indent() {
unsigned N = Indent;
while (N--) out << ' ';
}
public:
DiffConsumer(Module *L, Module *R)
: out(errs()), LModule(L), RModule(R), Differences(false), Indent(0) {}
bool hadDifferences() const { return Differences; }
void enterContext(Value *L, Value *R) {
contexts.push_back(DiffContext(L, R));
Indent += 2;
}
void exitContext() {
Differences |= contexts.back().Differences;
contexts.pop_back();
Indent -= 2;
}
void log(StringRef text) {
header();
indent();
out << text << '\n';
}
void logf(const DifferenceEngine::LogBuilder &Log) {
header();
indent();
unsigned arg = 0;
StringRef format = Log.getFormat();
while (true) {
size_t percent = format.find('%');
if (percent == StringRef::npos) {
out << format;
break;
}
assert(format[percent] == '%');
if (percent > 0) out << format.substr(0, percent);
switch (format[percent+1]) {
case '%': out << '%'; break;
case 'l': printValue(Log.getArgument(arg++), true); break;
case 'r': printValue(Log.getArgument(arg++), false); break;
default: llvm_unreachable("unknown format character");
}
format = format.substr(percent+2);
}
out << '\n';
}
void logd(const DifferenceEngine::DiffLogBuilder &Log) {
header();
for (unsigned I = 0, E = Log.getNumLines(); I != E; ++I) {
indent();
switch (Log.getLineKind(I)) {
case DifferenceEngine::DC_match:
out << " ";
Log.getLeft(I)->dump();
//printValue(Log.getLeft(I), true);
break;
case DifferenceEngine::DC_left:
out << "< ";
Log.getLeft(I)->dump();
//printValue(Log.getLeft(I), true);
break;
case DifferenceEngine::DC_right:
out << "> ";
Log.getRight(I)->dump();
//printValue(Log.getRight(I), false);
break;
}
//out << "\n";
}
}
};
}
static void diffGlobal(DifferenceEngine &Engine, Module *L, Module *R,
StringRef Name) {
// Drop leading sigils from the global name.
if (Name.startswith("@")) Name = Name.substr(1);
Function *LFn = L->getFunction(Name);
Function *RFn = R->getFunction(Name);
if (LFn && RFn)
Engine.diff(LFn, RFn);
else if (!LFn && !RFn)
errs() << "No function named @" << Name << " in either module\n";
else if (!LFn)
errs() << "No function named @" << Name << " in left module\n";
else
errs() << "No function named @" << Name << " in right module\n";
}
cl::opt<std::string> LeftFilename(cl::Positional,
cl::desc("<first file>"),
cl::Required);
cl::opt<std::string> RightFilename(cl::Positional,
cl::desc("<second file>"),
cl::Required);
cl::list<std::string> GlobalsToCompare(cl::Positional,
cl::desc("<globals to compare>"));
int main(int argc, char **argv) {
cl::ParseCommandLineOptions(argc, argv);
LLVMContext Context;
// Load both modules. Die if that fails.
Module *LModule = ReadModule(Context, LeftFilename);
Module *RModule = ReadModule(Context, RightFilename);
if (!LModule || !RModule) return 1;
DiffConsumer Consumer(LModule, RModule);
DifferenceEngine Engine(Context, Consumer);
// If any global names were given, just diff those.
if (!GlobalsToCompare.empty()) {
for (unsigned I = 0, E = GlobalsToCompare.size(); I != E; ++I)
diffGlobal(Engine, LModule, RModule, GlobalsToCompare[I]);
// Otherwise, diff everything in the module.
} else {
Engine.diff(LModule, RModule);
}
delete LModule;
delete RModule;
return Consumer.hadDifferences();
}