From: David Majnemer Date: Tue, 1 Sep 2015 21:23:58 +0000 (+0000) Subject: [MC] Add support for generating COFF CRCs X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=3d58bd6369de960bcd144318b6209ccdea200c3f;p=oota-llvm.git [MC] Add support for generating COFF CRCs COFF sections are accompanied with an auxiliary symbol which includes a checksum. This checksum used to be filled with just zero but this seems to upset LINK.exe when it is processing a /INCREMENTAL link job. Instead, fill the CheckSum field with the JamCRC of the section contents. This matches MSVC's behavior. This fixes PR19666. N.B. A rather simple implementation of JamCRC is given. It implements a byte-wise calculation using the method given by Sarwate. There are implementations with higher throughput like slice-by-eight and making use of PCLMULQDQ. We can switch to one of those techniques if it turns out to be a significant use of time. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246590 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/include/llvm/Support/JamCRC.h b/include/llvm/Support/JamCRC.h new file mode 100644 index 00000000000..20c28a5f8e4 --- /dev/null +++ b/include/llvm/Support/JamCRC.h @@ -0,0 +1,48 @@ +//===-- llvm/Support/JamCRC.h - Cyclic Redundancy Check ---------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains an implementation of JamCRC. +// +// We will use the "Rocksoft^tm Model CRC Algorithm" to describe the properties +// of this CRC: +// Width : 32 +// Poly : 04C11DB7 +// Init : FFFFFFFF +// RefIn : True +// RefOut : True +// XorOut : 00000000 +// Check : 340BC6D9 (result of CRC for "123456789") +// +// N.B. We permit flexibility of the "Init" value. Some consumers of this need +// it to be zero. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_SUPPORT_JAMCRC_H +#define LLVM_SUPPORT_JAMCRC_H + +#include "llvm/ADT/ArrayRef.h" +#include "llvm/Support/DataTypes.h" + +namespace llvm { +class JamCRC { +public: + JamCRC(uint32_t Init = 0xFFFFFFFFU) : CRC(Init) {} + + // \brief Update the CRC calculation with Data. + void update(ArrayRef Data); + + uint32_t getCRC() const { return CRC; } + +private: + uint32_t CRC; +}; +} // End of namespace llvm + +#endif diff --git a/lib/MC/WinCOFFObjectWriter.cpp b/lib/MC/WinCOFFObjectWriter.cpp index a0a11d42111..9abd1a15906 100644 --- a/lib/MC/WinCOFFObjectWriter.cpp +++ b/lib/MC/WinCOFFObjectWriter.cpp @@ -32,6 +32,7 @@ #include "llvm/Support/Debug.h" #include "llvm/Support/Endian.h" #include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/JamCRC.h" #include "llvm/Support/TimeValue.h" #include @@ -1029,6 +1030,7 @@ void WinCOFFObjectWriter::writeObject(MCAssembler &Asm, } } + SmallVector SectionContents; for (i = Sections.begin(), ie = Sections.end(), j = Asm.begin(), je = Asm.end(); (i != ie) && (j != je); ++i, ++j) { @@ -1047,7 +1049,33 @@ void WinCOFFObjectWriter::writeObject(MCAssembler &Asm, WriteZeros(SectionDataPadding); + // Save the contents of the section to a temporary buffer, we need this + // to CRC the data before we dump it into the object file. + SectionContents.clear(); + raw_svector_ostream VecOS(SectionContents); + raw_pwrite_stream &OldStream = getStream(); + // Redirect the output stream to our buffer. + setStream(VecOS); + // Fill our buffer with the section data. Asm.writeSectionData(&*j, Layout); + // Reset the stream back to what it was before. + setStream(OldStream); + + // Calculate our CRC with an initial value of '0', this is not how + // JamCRC is specified but it aligns with the expected output. + JamCRC JC(/*Init=*/0x00000000U); + JC.update(SectionContents); + + // Write the section contents to the object file. + getStream() << SectionContents; + + // Update the section definition auxiliary symbol to record the CRC. + COFFSection *Sec = SectionMap[&*j]; + COFFSymbol::AuxiliarySymbols &AuxSyms = Sec->Symbol->Aux; + assert(AuxSyms.size() == 1 && + AuxSyms[0].AuxType == ATSectionDefinition); + AuxSymbol &SecDef = AuxSyms[0]; + SecDef.Aux.SectionDefinition.CheckSum = JC.getCRC(); } if ((*i)->Relocations.size() > 0) { diff --git a/lib/Support/CMakeLists.txt b/lib/Support/CMakeLists.txt index a8a4df51661..badfd99b673 100644 --- a/lib/Support/CMakeLists.txt +++ b/lib/Support/CMakeLists.txt @@ -59,6 +59,7 @@ add_llvm_library(LLVMSupport IntEqClasses.cpp IntervalMap.cpp IntrusiveRefCntPtr.cpp + JamCRC.cpp LEB128.cpp LineIterator.cpp Locale.cpp diff --git a/lib/Support/JamCRC.cpp b/lib/Support/JamCRC.cpp new file mode 100644 index 00000000000..bc21c917d55 --- /dev/null +++ b/lib/Support/JamCRC.cpp @@ -0,0 +1,96 @@ +//===-- JamCRC.cpp - Cyclic Redundancy Check --------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains an implementation of JamCRC. +// +//===----------------------------------------------------------------------===// +// +// The implementation technique is the one mentioned in: +// D. V. Sarwate. 1988. Computation of cyclic redundancy checks via table +// look-up. Commun. ACM 31, 8 (August 1988) +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/JamCRC.h" + +using namespace llvm; + +static const uint32_t CRCTable[256] = { + 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, + 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, + 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, + 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, + 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, + 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, + 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, + 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, + 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, + 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, + 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, + 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, + 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, + 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, + 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, + 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, + 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, + 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, + 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, + 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, + 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, + 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, + 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, + 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, + 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, + 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, + 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, + 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, + 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, + 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, + 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, + 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, + 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, + 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, + 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, + 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, + 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, + 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, + 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, + 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, + 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, + 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, + 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, + 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, + 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, + 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, + 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, + 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, + 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, + 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, + 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, + 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, + 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, + 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, + 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, + 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, + 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, + 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, + 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, + 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, + 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, + 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, + 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, + 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d +}; + +void JamCRC::update(ArrayRef Data) { + for (char Byte : Data) { + int TableIdx = (CRC ^ Byte) & 0xff; + CRC = CRCTable[TableIdx] ^ (CRC >> 8); + } +} diff --git a/test/MC/COFF/basic-coff-64.s b/test/MC/COFF/basic-coff-64.s index 62e4eb92f85..1fa9280e0ca 100644 --- a/test/MC/COFF/basic-coff-64.s +++ b/test/MC/COFF/basic-coff-64.s @@ -93,7 +93,7 @@ _main: # @main // CHECK: Length: [[TextSize]] // CHECK: RelocationCount: 2 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0x8E1B6D20 // CHECK: Number: [[TextNum]] // CHECK: Selection: 0x0 // CHECK: } @@ -110,7 +110,7 @@ _main: # @main // CHECK: Length: [[DataSize]] // CHECK: RelocationCount: 0 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0x2B95CA92 // CHECK: Number: [[DataNum]] // CHECK: Selection: 0x0 // CHECK: } diff --git a/test/MC/COFF/basic-coff.s b/test/MC/COFF/basic-coff.s index 549825aacea..6aa247bdd29 100644 --- a/test/MC/COFF/basic-coff.s +++ b/test/MC/COFF/basic-coff.s @@ -93,7 +93,7 @@ L_.str: # @.str // CHECK: Length: 21 // CHECK: RelocationCount: 2 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0xC6461CBE // CHECK: Number: 1 // CHECK: Selection: 0x0 // CHECK: } @@ -110,7 +110,7 @@ L_.str: # @.str // CHECK: Length: 12 // CHECK: RelocationCount: 0 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0x2B95CA92 // CHECK: Number: 2 // CHECK: Selection: 0x0 // CHECK: } diff --git a/test/MC/COFF/symbol-fragment-offset-64.s b/test/MC/COFF/symbol-fragment-offset-64.s index 05b46bbb7e7..03077ce9429 100644 --- a/test/MC/COFF/symbol-fragment-offset-64.s +++ b/test/MC/COFF/symbol-fragment-offset-64.s @@ -114,7 +114,7 @@ _main: # @main // CHECK: Length: 48 // CHECK: RelocationCount: 6 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0x7BD396E3 // CHECK: Number: 1 // CHECK: Selection: 0x0 // CHECK: } @@ -131,7 +131,7 @@ _main: # @main // CHECK: Length: 35 // CHECK: RelocationCount: 0 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0xB0A4C21 // CHECK: Number: 2 // CHECK: Selection: 0x0 // CHECK: } diff --git a/test/MC/COFF/symbol-fragment-offset.s b/test/MC/COFF/symbol-fragment-offset.s index cc5040a99cc..c592fa4c0e7 100644 --- a/test/MC/COFF/symbol-fragment-offset.s +++ b/test/MC/COFF/symbol-fragment-offset.s @@ -114,7 +114,7 @@ L_.str2: // CHECK: Length: 45 // CHECK: RelocationCount: 6 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0xDED1DC2 // CHECK: Number: 1 // CHECK: Selection: 0x0 // CHECK: } @@ -131,7 +131,7 @@ L_.str2: // CHECK: Length: 35 // CHECK: RelocationCount: 0 // CHECK: LineNumberCount: 0 -// CHECK: Checksum: 0x0 +// CHECK: Checksum: 0xB0A4C21 // CHECK: Number: 2 // CHECK: Selection: 0x0 // CHECK: }