[lld] r251998 - [elf2] Implement R_X86_64_TPOFF32.
Michael Spencer via llvm-commits
llvm-commits at lists.llvm.org
Wed Nov 4 18:03:31 PST 2015
On Wed, Nov 4, 2015 at 4:32 PM, Rafael Espíndola
<rafael.espindola at gmail.com> wrote:
> I just noticed that I am getting different results with gold and bfd:
>
> Given:
> -------------------------------
> .global _start
> _start:
> movl %fs:a at tpoff, %eax
> .global a
> .section .tbss,"awT", at nobits
> .zero 0x10
> a:
> .long 0
> ----------------------------------
>
> lld produces
>
> _start:
> 11000: 64 8b 04 25 10 00 00 00 movl %fs:16, %eax
>
> gold produces
>
>
> _start:
> 4000e8: 64 8b 04 25 fc ff ff ff movl %fs:-4, %eax
>
> Is that expected?
>
> Cheers,
> Rafael
>
Fixed in r252131.
- Michael Spencer
>
>
> On 3 November 2015 at 17:39, Michael J. Spencer via llvm-commits
> <llvm-commits at lists.llvm.org> wrote:
>> Author: mspencer
>> Date: Tue Nov 3 16:39:09 2015
>> New Revision: 251998
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=251998&view=rev
>> Log:
>> [elf2] Implement R_X86_64_TPOFF32.
>>
>> This does not support TPOFF32 relocations to local symbols as the address calculations are separate. Support for this will be a separate patch.
>>
>> Modified:
>> lld/trunk/ELF/OutputSections.cpp
>> lld/trunk/ELF/OutputSections.h
>> lld/trunk/ELF/Target.cpp
>> lld/trunk/ELF/Writer.cpp
>> lld/trunk/test/elf2/tls.s
>>
>> Modified: lld/trunk/ELF/OutputSections.cpp
>> URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/OutputSections.cpp?rev=251998&r1=251997&r2=251998&view=diff
>> ==============================================================================
>> --- lld/trunk/ELF/OutputSections.cpp (original)
>> +++ lld/trunk/ELF/OutputSections.cpp Tue Nov 3 16:39:09 2015
>> @@ -644,6 +644,9 @@ typename ELFFile<ELFT>::uintX_t lld::elf
>> case SymbolBody::DefinedRegularKind: {
>> const auto &DR = cast<DefinedRegular<ELFT>>(S);
>> InputSectionBase<ELFT> &SC = DR.Section;
>> + if (DR.Sym.getType() == STT_TLS)
>> + return SC.OutSec->getVA() + SC.getOffset(DR.Sym) -
>> + Out<ELFT>::TlsInitImageVA;
>> return SC.OutSec->getVA() + SC.getOffset(DR.Sym);
>> }
>> case SymbolBody::DefinedCommonKind:
>>
>> Modified: lld/trunk/ELF/OutputSections.h
>> URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/OutputSections.h?rev=251998&r1=251997&r2=251998&view=diff
>> ==============================================================================
>> --- lld/trunk/ELF/OutputSections.h (original)
>> +++ lld/trunk/ELF/OutputSections.h Tue Nov 3 16:39:09 2015
>> @@ -353,6 +353,7 @@ private:
>> // globally accessible. Writer initializes them, so don't use them
>> // until Writer is initialized.
>> template <class ELFT> struct Out {
>> + typedef typename llvm::object::ELFFile<ELFT>::uintX_t uintX_t;
>> static DynamicSection<ELFT> *Dynamic;
>> static GnuHashTableSection<ELFT> *GnuHashTab;
>> static GotPltSection<ELFT> *GotPlt;
>> @@ -370,6 +371,7 @@ template <class ELFT> struct Out {
>> static StringTableSection<ELFT> *StrTab;
>> static SymbolTableSection<ELFT> *DynSymTab;
>> static SymbolTableSection<ELFT> *SymTab;
>> + static uintX_t TlsInitImageVA;
>> };
>>
>> template <class ELFT> DynamicSection<ELFT> *Out<ELFT>::Dynamic;
>> @@ -389,6 +391,7 @@ template <class ELFT> StringTableSection
>> template <class ELFT> StringTableSection<ELFT> *Out<ELFT>::StrTab;
>> template <class ELFT> SymbolTableSection<ELFT> *Out<ELFT>::DynSymTab;
>> template <class ELFT> SymbolTableSection<ELFT> *Out<ELFT>::SymTab;
>> +template <class ELFT> typename Out<ELFT>::uintX_t Out<ELFT>::TlsInitImageVA;
>> }
>> }
>> #endif
>>
>> Modified: lld/trunk/ELF/Target.cpp
>> URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Target.cpp?rev=251998&r1=251997&r2=251998&view=diff
>> ==============================================================================
>> --- lld/trunk/ELF/Target.cpp (original)
>> +++ lld/trunk/ELF/Target.cpp Tue Nov 3 16:39:09 2015
>> @@ -339,6 +339,9 @@ void X86_64TargetInfo::relocateOne(uint8
>> error("R_X86_64_32S out of range");
>> write32le(Loc, SA);
>> break;
>> + case R_X86_64_TPOFF32:
>> + write32le(Loc, SA);
>> + break;
>> default:
>> error("unrecognized reloc " + Twine(Type));
>> }
>>
>> Modified: lld/trunk/ELF/Writer.cpp
>> URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Writer.cpp?rev=251998&r1=251997&r2=251998&view=diff
>> ==============================================================================
>> --- lld/trunk/ELF/Writer.cpp (original)
>> +++ lld/trunk/ELF/Writer.cpp Tue Nov 3 16:39:09 2015
>> @@ -716,8 +716,10 @@ template <class ELFT> void Writer<ELFT>:
>> }
>>
>> if ((Sec->getFlags() & SHF_ALLOC) && (Sec->getFlags() & SHF_TLS)) {
>> - if (!TlsPhdr.p_vaddr)
>> + if (!TlsPhdr.p_vaddr) {
>> setPhdr(&TlsPhdr, PT_TLS, PF_R, FileOff, VA, 0, Sec->getAlign());
>> + Out<ELFT>::TlsInitImageVA = VA;
>> + }
>> if (Sec->getType() != SHT_NOBITS)
>> VA = RoundUpToAlignment(VA, Sec->getAlign());
>> uintX_t TVA = RoundUpToAlignment(VA + ThreadBSSOffset, Sec->getAlign());
>>
>> Modified: lld/trunk/test/elf2/tls.s
>> URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/elf2/tls.s?rev=251998&r1=251997&r2=251998&view=diff
>> ==============================================================================
>> --- lld/trunk/test/elf2/tls.s (original)
>> +++ lld/trunk/test/elf2/tls.s Tue Nov 3 16:39:09 2015
>> @@ -1,21 +1,34 @@
>> // REQUIRES: x86
>> // RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
>> // RUN: ld.lld2 %t -o %tout
>> -// RUN: llvm-readobj -sections -program-headers %tout | FileCheck %s
>> +// RUN: llvm-readobj -symbols -sections -program-headers %tout | FileCheck %s
>> +// RUN: llvm-objdump -d %tout | FileCheck %s --check-prefix=DIS
>>
>> .global _start
>> _start:
>> + movl %fs:a at tpoff, %eax
>> + movl %fs:b at tpoff, %eax
>> + movl %fs:c at tpoff, %eax
>> + movl %fs:d at tpoff, %eax
>>
>> + .global a
>> .section .tbss,"awT", at nobits
>> +a:
>> .long 0
>>
>> + .global b
>> .section .tdata,"awT", at progbits
>> +b:
>> .long 1
>>
>> + .global c
>> .section .thread_bss,"awT", at nobits
>> +c:
>> .long 0
>>
>> + .global d
>> .section .thread_data,"awT", at progbits
>> +d:
>> .long 2
>>
>> // CHECK: Name: .tdata
>> @@ -77,9 +90,9 @@ _start:
>> // CHECK-NEXT: SHF_WRITE
>> // CHECK-NEXT: ]
>>
>> -// 0x1100C = TBSS_ADDR + 4
>> +// 0x1200C = TBSS_ADDR + 4
>>
>> -// CHECK-NEXT: Address: 0x1100C
>> +// CHECK-NEXT: Address: 0x1200C
>> // CHECK-NEXT: Offset:
>> // CHECK-NEXT: Size: 4
>> // CHECK-NEXT: Link:
>> @@ -88,11 +101,49 @@ _start:
>> // CHECK-NEXT: EntrySize:
>> // CHECK-NEXT: }
>>
>> +// CHECK: Symbols [
>> +// CHECK: Name: a
>> +// CHECK-NEXT: Value: 0x8
>> +// CHECK-NEXT: Size:
>> +// CHECK-NEXT: Binding: Global
>> +// CHECK-NEXT: Type: TLS
>> +// CHECK-NEXT: Other: 0
>> +// CHECK-NEXT: Section: .tbss
>> +// CHECK-NEXT: }
>> +// CHECK-NEXT: Symbol {
>> +// CHECK-NEXT: Name: b
>> +// CHECK-NEXT: Value: 0x0
>> +// CHECK-NEXT: Size:
>> +// CHECK-NEXT: Binding: Global
>> +// CHECK-NEXT: Type: TLS
>> +// CHECK-NEXT: Other: 0
>> +// CHECK-NEXT: Section: .tdata
>> +// CHECK-NEXT: }
>> +// CHECK-NEXT: Symbol {
>> +// CHECK-NEXT: Name: c
>> +// CHECK-NEXT: Value: 0xC
>> +// CHECK-NEXT: Size:
>> +// CHECK-NEXT: Binding: Global
>> +// CHECK-NEXT: Type: TLS
>> +// CHECK-NEXT: Other: 0
>> +// CHECK-NEXT: Section: .thread_bss
>> +// CHECK-NEXT: }
>> +// CHECK-NEXT: Symbol {
>> +// CHECK-NEXT: Name: d
>> +// CHECK-NEXT: Value: 0x4
>> +// CHECK-NEXT: Size:
>> +// CHECK-NEXT: Binding: Global
>> +// CHECK-NEXT: Type: TLS
>> +// CHECK-NEXT: Other: 0
>> +// CHECK-NEXT: Section: .thread_data
>> +// CHECK-NEXT: }
>> +
>> // Check that the TLS NOBITS sections weren't added to the R/W PT_LOAD's size.
>>
>> // CHECK: ProgramHeaders [
>> // CHECK: Type: PT_LOAD
>> // CHECK: Type: PT_LOAD
>> +// CHECK: Type: PT_LOAD
>> // CHECK: FileSize: 8
>> // CHECK-NEXT: MemSize: 8
>> // CHECK-NEXT: Flags [
>> @@ -110,3 +161,10 @@ _start:
>> // CHECK-NEXT: ]
>> // CHECK-NEXT: Alignment:
>> // CHECK-NEXT: }
>> +
>> +// DIS: Disassembly of section .text:
>> +// DIS-NEXT: _start:
>> +// DIS-NEXT: 11000: {{.+}} movl %fs:8, %eax
>> +// DIS-NEXT: 11008: {{.+}} movl %fs:0, %eax
>> +// DIS-NEXT: 11010: {{.+}} movl %fs:12, %eax
>> +// DIS-NEXT: 11018: {{.+}} movl %fs:4, %eax
>>
>>
>> _______________________________________________
>> llvm-commits mailing list
>> llvm-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
More information about the llvm-commits
mailing list