diff options
| -rw-r--r-- | lld/COFF/Chunks.cpp | 15 | ||||
| -rw-r--r-- | lld/COFF/Symbols.cpp | 2 | ||||
| -rw-r--r-- | lld/COFF/Symbols.h | 5 | ||||
| -rw-r--r-- | lld/COFF/Writer.cpp | 6 | ||||
| -rw-r--r-- | lld/test/COFF/pdb-secrel-absolute.yaml | 84 | ||||
| -rw-r--r-- | lld/test/COFF/secidx-absolute.s | 33 | ||||
| -rw-r--r-- | lld/test/COFF/secrel-absolute.s | 14 |
7 files changed, 156 insertions, 3 deletions
diff --git a/lld/COFF/Chunks.cpp b/lld/COFF/Chunks.cpp index 1d5ae5571d2..56124acaf9a 100644 --- a/lld/COFF/Chunks.cpp +++ b/lld/COFF/Chunks.cpp @@ -52,6 +52,15 @@ static void add32(uint8_t *P, int32_t V) { write32le(P, read32le(P) + V); } static void add64(uint8_t *P, int64_t V) { write64le(P, read64le(P) + V); } static void or16(uint8_t *P, uint16_t V) { write16le(P, read16le(P) | V); } +static void applySecRel(const SectionChunk *Sec, uint8_t *Off, Defined *Sym) { + // Don't apply section relative relocations to absolute symbols in codeview + // debug info sections. MSVC does not treat such relocations as fatal errors, + // and they can be found in the standard library for linker-provided symbols + // like __guard_fids_table and __safe_se_handler_table. + if (!(isa<DefinedAbsolute>(Sym) && Sec->isCodeView())) + add32(Off, Sym->getSecrel()); +} + void SectionChunk::applyRelX64(uint8_t *Off, uint16_t Type, Defined *Sym, uint64_t P) const { uint64_t S = Sym->getRVA(); @@ -66,7 +75,7 @@ void SectionChunk::applyRelX64(uint8_t *Off, uint16_t Type, Defined *Sym, case IMAGE_REL_AMD64_REL32_4: add32(Off, S - P - 8); break; case IMAGE_REL_AMD64_REL32_5: add32(Off, S - P - 9); break; case IMAGE_REL_AMD64_SECTION: add16(Off, Sym->getSectionIndex()); break; - case IMAGE_REL_AMD64_SECREL: add32(Off, Sym->getSecrel()); break; + case IMAGE_REL_AMD64_SECREL: applySecRel(this, Off, Sym); break; default: fatal("unsupported relocation type 0x" + Twine::utohexstr(Type)); } @@ -81,7 +90,7 @@ void SectionChunk::applyRelX86(uint8_t *Off, uint16_t Type, Defined *Sym, case IMAGE_REL_I386_DIR32NB: add32(Off, S); break; case IMAGE_REL_I386_REL32: add32(Off, S - P - 4); break; case IMAGE_REL_I386_SECTION: add16(Off, Sym->getSectionIndex()); break; - case IMAGE_REL_I386_SECREL: add32(Off, Sym->getSecrel()); break; + case IMAGE_REL_I386_SECREL: applySecRel(this, Off, Sym); break; default: fatal("unsupported relocation type 0x" + Twine::utohexstr(Type)); } @@ -141,7 +150,7 @@ void SectionChunk::applyRelARM(uint8_t *Off, uint16_t Type, Defined *Sym, case IMAGE_REL_ARM_BRANCH20T: applyBranch20T(Off, S - P - 4); break; case IMAGE_REL_ARM_BRANCH24T: applyBranch24T(Off, S - P - 4); break; case IMAGE_REL_ARM_BLX23T: applyBranch24T(Off, S - P - 4); break; - case IMAGE_REL_ARM_SECREL: add32(Off, Sym->getSecrel()); break; + case IMAGE_REL_ARM_SECREL: applySecRel(this, Off, Sym); break; default: fatal("unsupported relocation type 0x" + Twine::utohexstr(Type)); } diff --git a/lld/COFF/Symbols.cpp b/lld/COFF/Symbols.cpp index 5c185a511dd..1cf2934a355 100644 --- a/lld/COFF/Symbols.cpp +++ b/lld/COFF/Symbols.cpp @@ -61,6 +61,8 @@ COFFSymbolRef DefinedCOFF::getCOFFSymbol() { return COFFSymbolRef(reinterpret_cast<const coff_symbol32 *>(Sym)); } +uint16_t DefinedAbsolute::OutputSectionIndex = 0; + static Chunk *makeImportThunk(DefinedImportData *S, uint16_t Machine) { if (Machine == AMD64) return make<ImportThunkChunkX64>(S); diff --git a/lld/COFF/Symbols.h b/lld/COFF/Symbols.h index 801fc87f91d..828744b8ff3 100644 --- a/lld/COFF/Symbols.h +++ b/lld/COFF/Symbols.h @@ -212,6 +212,11 @@ public: uint64_t getRVA() { return VA - Config->ImageBase; } void setVA(uint64_t V) { VA = V; } + // The sentinel absolute symbol section index. Section index relocations + // against absolute symbols resolve to this 16 bit number, and it is the + // largest valid section index plus one. This is written by the Writer. + static uint16_t OutputSectionIndex; + private: uint64_t VA; }; diff --git a/lld/COFF/Writer.cpp b/lld/COFF/Writer.cpp index d31f0c3d57a..c67fac59f92 100644 --- a/lld/COFF/Writer.cpp +++ b/lld/COFF/Writer.cpp @@ -219,6 +219,8 @@ uint64_t Defined::getSecrel() { uint64_t Defined::getSectionIndex() { if (auto *D = dyn_cast<DefinedRegular>(this)) return D->getChunk()->getOutputSection()->SectionIndex; + if (auto *D = dyn_cast<DefinedAbsolute>(this)) + return DefinedAbsolute::OutputSectionIndex; fatal("SECTION relocation points to a non-regular symbol: " + toString(*this)); } @@ -775,6 +777,10 @@ void Writer::setSectionPermissions() { // Write section contents to a mmap'ed file. void Writer::writeSections() { + // Record the section index that should be used when resolving a section + // relocation against an absolute symbol. + DefinedAbsolute::OutputSectionIndex = OutputSections.size() + 1; + uint8_t *Buf = Buffer->getBufferStart(); for (OutputSection *Sec : OutputSections) { uint8_t *SecBuf = Buf + Sec->getFileOff(); diff --git a/lld/test/COFF/pdb-secrel-absolute.yaml b/lld/test/COFF/pdb-secrel-absolute.yaml new file mode 100644 index 00000000000..61bcd562766 --- /dev/null +++ b/lld/test/COFF/pdb-secrel-absolute.yaml @@ -0,0 +1,84 @@ +# RUN: yaml2obj %s -o %t.obj +# RUN: lld-link -debug -entry:main -out:%t.exe -pdb:%t.pdb %t.obj +# RUN: llvm-pdbutil raw -symbols %t.pdb | FileCheck %s + +# There is an S_GDATA32 symbol record with .secrel32 and .secidx relocations in +# it in this debug info. This is similar to the relocations in the loadcfg.obj +# file in the MSVC CRT. We need to make sure that our relocation logic matches +# MSVC's for these absolute, linker-provided symbols. + +# CHECK: Mod 0000 | +# CHECK-NEXT: - S_GDATA32 [size = 36] `__guard_fids_table` +# CHECK-NEXT: type = 0x0022 (unsigned long), addr = 0003:0000 +# CHECK-NEXT: Mod 0001 | `* Linker *`: + +--- !COFF +header: + Machine: IMAGE_FILE_MACHINE_AMD64 + Characteristics: [ ] +sections: + - Name: '.debug$S' + Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ] + Alignment: 1 + Subsections: + - !Symbols + Records: + - Kind: S_GDATA32 + DataSym: + Type: 34 + DisplayName: __guard_fids_table + - !StringTable + Strings: + Relocations: + - VirtualAddress: 20 + SymbolName: __guard_fids_table + Type: IMAGE_REL_AMD64_SECREL + - VirtualAddress: 24 + SymbolName: __guard_fids_table + Type: IMAGE_REL_AMD64_SECTION + - Name: '.text$mn' + Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ] + Alignment: 16 + SectionData: 488D0500000000C3 + Relocations: + - VirtualAddress: 3 + SymbolName: __guard_fids_table + Type: IMAGE_REL_AMD64_REL32 +symbols: + - Name: '.debug$S' + Value: 0 + SectionNumber: 1 + SimpleType: IMAGE_SYM_TYPE_NULL + ComplexType: IMAGE_SYM_DTYPE_NULL + StorageClass: IMAGE_SYM_CLASS_STATIC + SectionDefinition: + Length: 372 + NumberOfRelocations: 6 + NumberOfLinenumbers: 0 + CheckSum: 0 + Number: 0 + - Name: '.text$mn' + Value: 0 + SectionNumber: 2 + SimpleType: IMAGE_SYM_TYPE_NULL + ComplexType: IMAGE_SYM_DTYPE_NULL + StorageClass: IMAGE_SYM_CLASS_STATIC + SectionDefinition: + Length: 8 + NumberOfRelocations: 1 + NumberOfLinenumbers: 0 + CheckSum: 1092178131 + Number: 0 + - Name: main + Value: 0 + SectionNumber: 2 + SimpleType: IMAGE_SYM_TYPE_NULL + ComplexType: IMAGE_SYM_DTYPE_FUNCTION + StorageClass: IMAGE_SYM_CLASS_EXTERNAL + - Name: __guard_fids_table + Value: 0 + SectionNumber: 0 + SimpleType: IMAGE_SYM_TYPE_NULL + ComplexType: IMAGE_SYM_DTYPE_NULL + StorageClass: IMAGE_SYM_CLASS_EXTERNAL +... diff --git a/lld/test/COFF/secidx-absolute.s b/lld/test/COFF/secidx-absolute.s new file mode 100644 index 00000000000..bfe7136b31d --- /dev/null +++ b/lld/test/COFF/secidx-absolute.s @@ -0,0 +1,33 @@ +# RUN: llvm-mc %s -filetype=obj -triple=x86_64-windows-msvc -o %t.obj +# RUN: lld-link -entry:main -nodefaultlib %t.obj -out:%t.exe +# RUN: llvm-readobj %t.exe -sections -section-data | FileCheck %s + +# Section relocations against absolute symbols resolve to the last real ouput +# section index plus one. + +.text +.global main +main: +ret + +.section .rdata,"dr" +.secidx __guard_fids_table + +# CHECK: Sections [ +# CHECK: Section { +# CHECK: Number: 1 +# CHECK: Name: .rdata (2E 72 64 61 74 61 00 00) +# CHECK: SectionData ( +# CHECK: 0000: 0300 |..| +# CHECK: ) +# CHECK: } +# CHECK: Section { +# CHECK: Number: 2 +# CHECK: Name: .text (2E 74 65 78 74 00 00 00) +# CHECK: VirtualSize: 0x1 +# CHECK: SectionData ( +# CHECK: 0000: C3 |.| +# CHECK: ) +# CHECK: } +# CHECK-NOT: Section +# CHECK: ] diff --git a/lld/test/COFF/secrel-absolute.s b/lld/test/COFF/secrel-absolute.s new file mode 100644 index 00000000000..69b5ab92991 --- /dev/null +++ b/lld/test/COFF/secrel-absolute.s @@ -0,0 +1,14 @@ +# RUN: llvm-mc %s -filetype=obj -triple=x86_64-windows-msvc -o %t.obj +# RUN: not lld-link -entry:main -nodefaultlib %t.obj -out:%t.exe 2>&1 | FileCheck %s + +# secrel relocations against absolute symbols are errors. + +# CHECK: SECREL relocation points to a non-regular symbol: __guard_fids_table + +.text +.global main +main: +ret + +.section .rdata,"dr" +.secrel32 __guard_fids_table |
