| //===- fpcmp.cpp - A fuzzy "cmp" that permits floating point noise --------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by the LLVM research group and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // fpcmp is a tool that basically works like the 'cmp' tool, except that it can |
| // tolerate errors due to floating point noise, with the -r option. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Support/CommandLine.h" |
| #include "llvm/Support/FileUtilities.h" |
| #include <iostream> |
| #include <cmath> |
| |
| using namespace llvm; |
| |
| namespace { |
| cl::opt<std::string> |
| File1(cl::Positional, cl::desc("<input file #1>"), cl::Required); |
| cl::opt<std::string> |
| File2(cl::Positional, cl::desc("<input file #2>"), cl::Required); |
| |
| cl::opt<double> |
| RelTolerance("r", cl::desc("Relative error tolerated"), cl::init(0)); |
| cl::opt<double> |
| AbsTolerance("a", cl::desc("Absolute error tolerated"), cl::init(0)); |
| } |
| |
| |
| /// OpenFile - mmap the specified file into the address space for reading, and |
| /// return the length and address of the buffer. |
| static void OpenFile(const std::string &Filename, unsigned &Len, char* &BufPtr){ |
| BufPtr = (char*)ReadFileIntoAddressSpace(Filename, Len); |
| if (BufPtr == 0) { |
| std::cerr << "Error: cannot open file '" << Filename << "'\n"; |
| exit(2); |
| } |
| } |
| |
| static bool isNumberChar(char C) { |
| switch (C) { |
| case '0': case '1': case '2': case '3': case '4': |
| case '5': case '6': case '7': case '8': case '9': |
| case '.': case '+': case '-': |
| case 'e': |
| case 'E': return true; |
| default: return false; |
| } |
| } |
| |
| static char *BackupNumber(char *Pos, char *FirstChar) { |
| // If we didn't stop in the middle of a number, don't backup. |
| if (!isNumberChar(*Pos)) return Pos; |
| |
| // Otherwise, return to the start of the number. |
| while (Pos > FirstChar && isNumberChar(Pos[-1])) |
| --Pos; |
| return Pos; |
| } |
| |
| static void CompareNumbers(char *&F1P, char *&F2P, char *F1End, char *F2End) { |
| char *F1NumEnd, *F2NumEnd; |
| double V1 = 0.0, V2 = 0.0; |
| // If we stop on numbers, compare their difference. |
| if (isNumberChar(*F1P) && isNumberChar(*F2P)) { |
| V1 = strtod(F1P, &F1NumEnd); |
| V2 = strtod(F2P, &F2NumEnd); |
| } else { |
| // Otherwise, the diff failed. |
| F1NumEnd = F1P; |
| F2NumEnd = F2P; |
| } |
| |
| if (F1NumEnd == F1P || F2NumEnd == F2P) { |
| std::cerr << "Comparison failed, not a numeric difference.\n"; |
| exit(1); |
| } |
| |
| // Check to see if these are inside the absolute tolerance |
| if (AbsTolerance < std::abs(V1-V2)) { |
| // Nope, check the relative tolerance... |
| double Diff; |
| if (V2) |
| Diff = std::abs(V1/V2 - 1.0); |
| else if (V1) |
| Diff = std::abs(V2/V1 - 1.0); |
| else |
| Diff = 0; // Both zero. |
| if (Diff > RelTolerance) { |
| std::cerr << "Compared: " << V1 << " and " << V2 << ": diff = " |
| << Diff << "\n"; |
| std::cerr << "Out of tolerance: rel/abs: " << RelTolerance |
| << "/" << AbsTolerance << "\n"; |
| exit(1); |
| } |
| } |
| |
| // Otherwise, advance our read pointers to the end of the numbers. |
| F1P = F1NumEnd; F2P = F2NumEnd; |
| } |
| |
| // PadFileIfNeeded - If the files are not identical, we will have to be doing |
| // numeric comparisons in here. There are bad cases involved where we (i.e., |
| // strtod) might run off the beginning or end of the file if it starts or ends |
| // with a number. Because of this, if needed, we pad the file so that it starts |
| // and ends with a null character. |
| static void PadFileIfNeeded(char *&FileStart, char *&FileEnd, char *&FP) { |
| if (isNumberChar(FileStart[0]) || isNumberChar(FileEnd[-1])) { |
| unsigned FileLen = FileEnd-FileStart; |
| char *NewFile = new char[FileLen+2]; |
| NewFile[0] = 0; // Add null padding |
| NewFile[FileLen+1] = 0; // Add null padding |
| memcpy(NewFile+1, FileStart, FileLen); |
| FP = NewFile+(FP-FileStart)+1; |
| FileStart = NewFile+1; |
| FileEnd = FileStart+FileLen; |
| } |
| } |
| |
| int main(int argc, char **argv) { |
| cl::ParseCommandLineOptions(argc, argv); |
| |
| // mmap in the files. |
| unsigned File1Len, File2Len; |
| char *File1Start, *File2Start; |
| OpenFile(File1, File1Len, File1Start); |
| OpenFile(File2, File2Len, File2Start); |
| |
| // Okay, now that we opened the files, scan them for the first difference. |
| char *File1End = File1Start+File1Len; |
| char *File2End = File2Start+File2Len; |
| char *F1P = File1Start; |
| char *F2P = File2Start; |
| |
| // Scan for the end of file or first difference. |
| while (F1P < File1End && F2P < File2End && *F1P == *F2P) |
| ++F1P, ++F2P; |
| |
| // Common case: identifical files. |
| if (F1P == File1End && F2P == File2End) return 0; |
| |
| // If the files need padding, do so now. |
| PadFileIfNeeded(File1Start, File1End, F1P); |
| PadFileIfNeeded(File2Start, File2End, F2P); |
| |
| while (1) { |
| // Scan for the end of file or next difference. |
| while (F1P < File1End && F2P < File2End && *F1P == *F2P) |
| ++F1P, ++F2P; |
| |
| if (F1P >= File1End || F2P >= File2End) break; |
| |
| // Okay, we must have found a difference. Backup to the start of the |
| // current number each stream is at so that we can compare from the |
| // beginning. |
| F1P = BackupNumber(F1P, File1Start); |
| F2P = BackupNumber(F2P, File2Start); |
| |
| // Now that we are at the start of the numbers, compare them, exiting if |
| // they don't match. |
| CompareNumbers(F1P, F2P, File1End, File2End); |
| } |
| |
| // Okay, we reached the end of file. If both files are at the end, we |
| // succeeded. |
| bool F1AtEnd = F1P >= File1End; |
| bool F2AtEnd = F2P >= File2End; |
| if (F1AtEnd & F2AtEnd) return 0; |
| |
| // Otherwise, we might have run off the end due to a number: backup and retry. |
| if (F1AtEnd && isNumberChar(F1P[-1])) --F1P; |
| if (F2AtEnd && isNumberChar(F2P[-1])) --F2P; |
| F1P = BackupNumber(F1P, File1Start); |
| F2P = BackupNumber(F2P, File2Start); |
| |
| // Now that we are at the start of the numbers, compare them, exiting if |
| // they don't match. |
| CompareNumbers(F1P, F2P, File1End, File2End); |
| |
| // If we found the end, we succeeded. |
| if (F1P >= File1End && F2P >= File2End) return 0; |
| |
| return 1; |
| } |
| |