Magic-Mirror/llvm-capstone
1
0
Fork 0
mirror of https://github.com/capstone-engine/llvm-capstone.git synced 2025-02-05 00:49:43 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Document and test the first few .got.plt entries.

Browse Source 
llvm-svn: 268945
This commit is contained in:
Rafael Espindola 2016-05-09 18:12:15 +00:00
parent e34ead8269
commit 4ee6cb3a70
3 changed files with 38 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
lld/ELF/Target.cpp
View File

@ -531,6 +531,10 @@ RelExpr X86_64TargetInfo::getRelExpr(uint32_t Type, const SymbolBody &S) const {
}
void X86_64TargetInfo::writeGotPltHeader(uint8_t *Buf) const {
// The first entry holds the value of _DYNAMIC. It is not clear why that is
// required, but it is documented in the psabi and the glibc dynamic linker
// seems to use it (not that this is relevant for linking ld.so, not any
// other program).
write64le(Buf, Out<ELF64LE>::Dynamic->getVA());
}

4
lld/ELF/Target.h
View File

@ -78,7 +78,11 @@ public:
uint32_t TlsOffsetRel;
unsigned PltEntrySize = 8;
unsigned PltZeroSize = 0;
// At least on x86_64 positions 1 and 2 are used by the first plt entry
// to support lazy loading.
unsigned GotPltHeaderEntriesNum = 3;
uint32_t ThunkSize = 0;
bool UseLazyBinding = false;

30
lld/test/ELF/got-plt-header.s Normal file
View File

@ -0,0 +1,30 @@
// RUN: llvm-mc %s -o %t.o -filetype=obj -triple=x86_64-pc-linux
// RUN: ld.lld %t.o -o %t.so -shared
// RUN: llvm-readobj -s -section-data %t.so | FileCheck %s
call foo@plt
// Check that the first .got.plt entry has the address of the dynamic table.
// CHECK: Type: SHT_DYNAMIC
// CHECK-NEXT: Flags [
// CHECK-NEXT: SHF_ALLOC
// CHECK-NEXT: SHF_WRITE
// CHECK-NEXT: ]
// CHECK-NEXT: Address: 0x2000
// CHECK: Name: .got.plt
// CHECK-NEXT: Type: SHT_PROGBITS
// CHECK-NEXT: Flags [
// CHECK-NEXT: SHF_ALLOC
// CHECK-NEXT: SHF_WRITE
// CHECK-NEXT: ]
// CHECK-NEXT: Address: 0x3000
// CHECK-NEXT: Offset: 0x3000
// CHECK-NEXT: Size: 32
// CHECK-NEXT: Link: 0
// CHECK-NEXT: Info: 0
// CHECK-NEXT: AddressAlignment: 8
// CHECK-NEXT: EntrySize: 0
// CHECK-NEXT: SectionData (
// CHECK-NEXT: 0000: 00200000 00000000 00000000 00000000