[ELF][MIPS] Fix initialization of TLS-related GOT entries

This patch allows static linking of TLS code. To do that it fixes
GOT entries initialization.

If TLS-related GOT entry created for a preemptible symbol i.e. has
a corresponding dynamic relocation, leave the entry initialized by zero.
Write down adjusted TLS symbol's values otherwise. For the adjustments
calculation use offsets for thread-local storage.

https://www.linux-mips.org/wiki/NPTL

llvm-svn: 280914
This commit is contained in:
Simon Atanasyan
2016-09-08 09:07:19 +00:00
parent af52f6af22
commit 919a58c456
6 changed files with 179 additions and 89 deletions

View File

@@ -261,7 +261,7 @@ template <class ELFT> void GotSection<ELFT>::finalize() {
this->Header.sh_size = EntriesNum * sizeof(uintX_t);
}
template <class ELFT> void GotSection<ELFT>::writeMipsGot(uint8_t *&Buf) {
template <class ELFT> void GotSection<ELFT>::writeMipsGot(uint8_t *Buf) {
// Set the MSB of the second GOT slot. This is not required by any
// MIPS ABI documentation, though.
//
@@ -293,11 +293,38 @@ template <class ELFT> void GotSection<ELFT>::writeMipsGot(uint8_t *&Buf) {
};
std::for_each(std::begin(MipsLocal), std::end(MipsLocal), AddEntry);
std::for_each(std::begin(MipsGlobal), std::end(MipsGlobal), AddEntry);
// Initialize TLS-related GOT entries. If the entry has a corresponding
// dynamic relocations, leave it initialized by zero. Write down adjusted
// TLS symbol's values otherwise. To calculate the adjustments use offsets
// for thread-local storage.
// https://www.linux-mips.org/wiki/NPTL
if (TlsIndexOff != -1U && !Config->Pic)
write<uintX_t, ELFT::TargetEndianness, sizeof(uintX_t)>(Buf + TlsIndexOff,
1);
for (const SymbolBody *B : Entries) {
if (!B || B->isPreemptible())
continue;
uintX_t VA = B->getVA<ELFT>();
if (B->GotIndex != -1U) {
uint8_t *Entry = Buf + B->GotIndex * sizeof(uintX_t);
write<uintX_t, ELFT::TargetEndianness, sizeof(uintX_t)>(Entry,
VA - 0x7000);
}
if (B->GlobalDynIndex != -1U) {
uint8_t *Entry = Buf + B->GlobalDynIndex * sizeof(uintX_t);
write<uintX_t, ELFT::TargetEndianness, sizeof(uintX_t)>(Entry, 1);
Entry += sizeof(uintX_t);
write<uintX_t, ELFT::TargetEndianness, sizeof(uintX_t)>(Entry,
VA - 0x8000);
}
}
}
template <class ELFT> void GotSection<ELFT>::writeTo(uint8_t *Buf) {
if (Config->EMachine == EM_MIPS)
if (Config->EMachine == EM_MIPS) {
writeMipsGot(Buf);
return;
}
for (const SymbolBody *B : Entries) {
uint8_t *Entry = Buf;
Buf += sizeof(uintX_t);

View File

@@ -181,7 +181,7 @@ private:
MipsGotEntries MipsGlobal;
// Write MIPS-specific parts of the GOT.
void writeMipsGot(uint8_t *&Buf);
void writeMipsGot(uint8_t *Buf);
};
template <class ELFT>

View File

@@ -93,7 +93,7 @@ handleMipsTlsRelocation(uint32_t Type, SymbolBody &Body,
InputSectionBase<ELFT> &C, typename ELFT::uint Offset,
typename ELFT::uint Addend, RelExpr Expr) {
if (Expr == R_MIPS_TLSLD) {
if (Out<ELFT>::Got->addTlsIndex())
if (Out<ELFT>::Got->addTlsIndex() && Config->Pic)
Out<ELFT>::RelaDyn->addReloc({Target->TlsModuleIndexRel, Out<ELFT>::Got,
Out<ELFT>::Got->getTlsIndexOff(), false,
nullptr, 0});
@@ -101,7 +101,7 @@ handleMipsTlsRelocation(uint32_t Type, SymbolBody &Body,
return 1;
}
if (Target->isTlsGlobalDynamicRel(Type)) {
if (Out<ELFT>::Got->addDynTlsEntry(Body)) {
if (Out<ELFT>::Got->addDynTlsEntry(Body) && Body.isPreemptible()) {
typedef typename ELFT::uint uintX_t;
uintX_t Off = Out<ELFT>::Got->getGlobalDynOffset(Body);
Out<ELFT>::RelaDyn->addReloc(
@@ -666,9 +666,9 @@ static void scanRelocs(InputSectionBase<ELFT> &C, ArrayRef<RelTy> Rels) {
// for detailed description:
// ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf
Out<ELFT>::Got->addMipsEntry(Body, Addend, Expr);
if (Body.isTls())
if (Body.isTls() && Body.isPreemptible())
AddDyn({Target->TlsGotRel, Out<ELFT>::Got, Body.getGotOffset<ELFT>(),
!Preemptible, &Body, 0});
false, &Body, 0});
continue;
}

View File

@@ -1,86 +1,112 @@
# Check MIPS TLS 64-bit relocations handling.
# RUN: llvm-mc -filetype=obj -triple=mips64-unknown-linux \
# RUN: %p/Inputs/mips-dynamic.s -o %t.so.o
# RUN: %p/Inputs/mips-tls.s -o %t.so.o
# RUN: ld.lld -shared %t.so.o -o %t.so
# RUN: llvm-mc -filetype=obj -triple=mips64-unknown-linux %s -o %t.o
# RUN: ld.lld %t.o %t.so -o %t.exe
# RUN: llvm-objdump -d -s -t %t.exe | FileCheck -check-prefix=DIS %s
# RUN: llvm-readobj -r -mips-plt-got %t.exe | FileCheck %s
# RUN: ld.lld -shared %t.o %t.so -o %t-out.so
# RUN: llvm-objdump -d -s -t %t-out.so | FileCheck -check-prefix=DIS-SO %s
# RUN: llvm-readobj -r -mips-plt-got %t-out.so | FileCheck -check-prefix=SO %s
# REQUIRES: mips
# DIS: __start:
# DIS-NEXT: 20000: 24 62 80 28 addiu $2, $3, -32728
# DIS-NEXT: 20004: 24 62 80 38 addiu $2, $3, -32712
# DIS-NEXT: 20008: 8f 82 80 20 lw $2, -32736($gp)
# DIS-NEXT: 20000: 24 62 80 20 addiu $2, $3, -32736
# DIS-NEXT: 20004: 24 62 80 30 addiu $2, $3, -32720
# DIS-NEXT: 20008: 24 62 80 38 addiu $2, $3, -32712
# DIS-NEXT: 2000c: 24 62 80 48 addiu $2, $3, -32696
# DIS-NEXT: 20010: 24 62 80 58 addiu $2, $3, -32680
# DIS: Contents of section .got:
# DIS_NEXT: 30008 00000000 00000000 80000000 00000000
# DIS_NEXT: 30018 00000000 00020000 00000000 00000000
# DIS_NEXT: 30028 00000000 00000004 00000000 00000000
# DIS_NEXT: 30038 00000000 00000000 00000000 00000004
# DIS-NEXT: 30008 00000000 00000000 80000000 00000000
# DIS-NEXT: 30018 00000000 00000000 00000000 00000000
# DIS-NEXT: 30028 00000000 00000000 00000000 00000001
# DIS-NEXT: 30038 00000000 00000000 00000000 00000001
# DIS-NEXT: 30048 ffffffff ffff8004 ffffffff ffff9004
# DIS: 0000000000030000 l .tdata 00000000 .tdata
# DIS: 0000000000030000 l .tdata 00000000 loc
# DIS: 0000000000000004 g .tdata 00000000 foo
# DIS: 0000000000000004 g .tdata 00000000 bar
# DIS: 0000000000000000 g *UND* 00000000 foo
# CHECK: Relocations [
# CHECK-NEXT: Section (7) .rela.dyn {
# CHECK-NEXT: 0x30020 R_MIPS_TLS_DTPMOD64/R_MIPS_NONE/R_MIPS_NONE - 0x0
# CHECK-NEXT: 0x30028 R_MIPS_TLS_DTPREL64/R_MIPS_NONE/R_MIPS_NONE - 0x0
# CHECK-NEXT: 0x30030 R_MIPS_TLS_DTPMOD64/R_MIPS_NONE/R_MIPS_NONE - 0x0
# CHECK-NEXT: 0x30040 R_MIPS_TLS_TPREL64/R_MIPS_NONE/R_MIPS_NONE - 0x4
# CHECK-NEXT: 0x30018 R_MIPS_TLS_DTPMOD64/R_MIPS_NONE/R_MIPS_NONE foo 0x0
# CHECK-NEXT: 0x30020 R_MIPS_TLS_DTPREL64/R_MIPS_NONE/R_MIPS_NONE foo 0x0
# CHECK-NEXT: 0x30028 R_MIPS_TLS_TPREL64/R_MIPS_NONE/R_MIPS_NONE foo 0x0
# CHECK-NEXT: }
# CHECK-NEXT: ]
# CHECK-NEXT: Primary GOT {
# CHECK-NEXT: Canonical gp value: 0x37FF8
# CHECK-NEXT: Reserved entries [
# CHECK-NEXT: Entry {
# CHECK-NEXT: Address: 0x30008
# CHECK-NEXT: Access: -32752
# CHECK-NEXT: Initial: 0x0
# CHECK-NEXT: Purpose: Lazy resolver
# CHECK-NEXT: }
# CHECK-NEXT: Entry {
# CHECK-NEXT: Address: 0x30010
# CHECK-NEXT: Access: -32744
# CHECK-NEXT: Initial: 0x80000000
# CHECK-NEXT: Purpose: Module pointer (GNU extension)
# CHECK-NEXT: }
# CHECK-NEXT: ]
# CHECK: ]
# CHECK-NEXT: Local entries [
# CHECK-NEXT: ]
# CHECK-NEXT: Global entries [
# CHECK-NEXT: Entry {
# CHECK-NEXT: Address: 0x30018
# CHECK-NEXT: Access: -32736
# CHECK-NEXT: Initial: 0x0
# CHECK-NEXT: Value: 0x0
# CHECK-NEXT: Type: Function
# CHECK-NEXT: Section: Undefined
# CHECK-NEXT: Name: foo0
# CHECK-NEXT: }
# CHECK-NEXT: ]
# CHECK-NEXT: Number of TLS and multi-GOT entries: 5
# ^-- 0x30020 / -32728 - R_MIPS_TLS_GD - R_MIPS_TLS_DTPMOD32 foo
# ^-- 0x30028 / -32720 - R_MIPS_TLS_DTPREL32 foo
# ^-- 0x30030 / -32712 - R_MIPS_TLS_LDM - R_MIPS_TLS_DTPMOD32 loc
# ^-- 0x30038 / -32704
# ^-- 0x30040 / -32696 - R_MIPS_TLS_GOTTPREL - R_MIPS_TLS_TPREL32
# CHECK-NEXT: Number of TLS and multi-GOT entries: 8
# ^-- -32736 R_MIPS_TLS_GD R_MIPS_TLS_DTPMOD64 foo
# ^-- -32728 R_MIPS_TLS_DTPREL64 foo
# ^-- -32720 R_MIPS_TLS_GOTTPREL R_MIPS_TLS_TPREL64 foo
# ^-- -32712 R_MIPS_TLS_LDM 1 loc
# ^-- -32704 0 loc
# ^-- -32696 R_MIPS_TLS_GD 1 bar
# ^-- -32688 VA - 0x8000 bar
# ^-- -32680 R_MIPS_TLS_GOTTPREL VA - 0x7000 bar
# DIS-SO: Contents of section .got:
# DIS-SO-NEXT: 20008 00000000 00000000 80000000 00000000
# DIS-SO-NEXT: 20018 00000000 00000000 00000000 00000000
# DIS-SO-NEXT: 20028 00000000 00000000 00000000 00000000
# DIS-SO-NEXT: 20038 00000000 00000000 00000000 00000000
# DIS-SO-NEXT: 20048 00000000 00000000 00000000 00000000
# SO: Relocations [
# SO-NEXT: Section (7) .rela.dyn {
# SO-NEXT: 0x20030 R_MIPS_TLS_DTPMOD64/R_MIPS_NONE/R_MIPS_NONE - 0x0
# SO-NEXT: 0x20040 R_MIPS_TLS_DTPMOD64/R_MIPS_NONE/R_MIPS_NONE bar 0x0
# SO-NEXT: 0x20048 R_MIPS_TLS_DTPREL64/R_MIPS_NONE/R_MIPS_NONE bar 0x0
# SO-NEXT: 0x20050 R_MIPS_TLS_TPREL64/R_MIPS_NONE/R_MIPS_NONE bar 0x0
# SO-NEXT: 0x20018 R_MIPS_TLS_DTPMOD64/R_MIPS_NONE/R_MIPS_NONE foo 0x0
# SO-NEXT: 0x20020 R_MIPS_TLS_DTPREL64/R_MIPS_NONE/R_MIPS_NONE foo 0x0
# SO-NEXT: 0x20028 R_MIPS_TLS_TPREL64/R_MIPS_NONE/R_MIPS_NONE foo 0x0
# SO-NEXT: }
# SO-NEXT: ]
# SO-NEXT: Primary GOT {
# SO-NEXT: Canonical gp value: 0x27FF8
# SO-NEXT: Reserved entries [
# SO: ]
# SO-NEXT: Local entries [
# SO-NEXT: ]
# SO-NEXT: Global entries [
# SO-NEXT: ]
# SO-NEXT: Number of TLS and multi-GOT entries: 8
# ^-- 0x20018 R_MIPS_TLS_GD R_MIPS_TLS_DTPMOD64 foo
# ^-- 0x20020 R_MIPS_TLS_DTPREL64 foo
# ^-- 0x20028 R_MIPS_TLS_GOTTPREL R_MIPS_TLS_TPREL64 foo
# ^-- 0x20030 R_MIPS_TLS_LDM R_MIPS_TLS_DTPMOD64 loc
# ^-- 0x20038 0 loc
# ^-- 0x20040 R_MIPS_TLS_GD R_MIPS_TLS_DTPMOD64 bar
# ^-- 0x20048 R_MIPS_TLS_DTPREL64 bar
# ^-- 0x20050 R_MIPS_TLS_GOTTPREL R_MIPS_TLS_TPREL64 bar
.text
.global __start
__start:
addiu $2, $3, %tlsgd(foo) # R_MIPS_TLS_GD
addiu $2, $3, %tlsldm(loc) # R_MIPS_TLS_LDM
lw $2, %got(foo0)($gp)
addiu $2, $3, %gottprel(foo) # R_MIPS_TLS_GOTTPREL
addiu $2, $3, %tlsldm(loc) # R_MIPS_TLS_LDM
addiu $2, $3, %tlsgd(bar) # R_MIPS_TLS_GD
addiu $2, $3, %gottprel(bar) # R_MIPS_TLS_GOTTPREL
.section .tdata,"awT",%progbits
.global foo
.global bar
loc:
.word 0
foo:
bar:
.word 0

View File

@@ -7,17 +7,22 @@
# REQUIRES: mips
# CHECK: Contents of section .got:
# CHECK-NEXT: 30008 00000000 80000000 00000001 ffff8000
# CHECK-NEXT: 30018 00000001 00000000 ffff9000
# CHECK: Contents of section .data:
# CHECK-NEXT: 40000 00020004 ffff8004 ffff9004
# CHECK-NEXT: 40000 0002000c ffff8004 ffff9004
#
# CHECK: SYMBOL TABLE:
# CHECK: 00020004 .text 00000000 __tls_get_addr
# CHECK: 0002000c .text 00000000 __tls_get_addr
# CHECK: 00000000 g .tdata 00000000 tls1
.text
.global __start
__start:
nop
addiu $2, $3, %tlsgd(tls1) # R_MIPS_TLS_GD
addiu $2, $3, %tlsldm(tls2) # R_MIPS_TLS_LDM
addiu $2, $3, %gottprel(tls1) # R_MIPS_TLS_GOTTPREL
.global __tls_get_addr
__tls_get_addr:
@@ -33,4 +38,5 @@ loc:
.global tls1
tls1:
.word __tls_get_addr
tls2:
.word 0

View File

@@ -4,74 +4,105 @@
# RUN: %p/Inputs/mips-tls.s -o %t.so.o
# RUN: ld.lld -shared %t.so.o -o %t.so
# RUN: llvm-mc -filetype=obj -triple=mips-unknown-linux %s -o %t.o
# RUN: ld.lld %t.o %t.so -o %t.exe
# RUN: llvm-objdump -d -s -t %t.exe | FileCheck -check-prefix=DIS %s
# RUN: llvm-readobj -r -mips-plt-got %t.exe | FileCheck %s
# RUN: ld.lld -shared %t.o %t.so -o %t-out.so
# RUN: llvm-objdump -d -s -t %t-out.so | FileCheck -check-prefix=DIS-SO %s
# RUN: llvm-readobj -r -mips-plt-got %t-out.so | FileCheck -check-prefix=SO %s
# REQUIRES: mips
# DIS: __start:
# DIS-NEXT: 20000: 24 62 80 1c addiu $2, $3, -32740
# DIS-NEXT: 20004: 24 62 80 24 addiu $2, $3, -32732
# DIS-NEXT: 20008: 8f 82 80 18 lw $2, -32744($gp)
# DIS-NEXT: 20000: 24 62 80 18 addiu $2, $3, -32744
# DIS-NEXT: 20004: 24 62 80 20 addiu $2, $3, -32736
# DIS-NEXT: 20008: 24 62 80 24 addiu $2, $3, -32732
# DIS-NEXT: 2000c: 24 62 80 2c addiu $2, $3, -32724
# DIS-NEXT: 20010: 24 62 80 34 addiu $2, $3, -32716
# DIS: Contents of section .got:
# DIS_NEXT: 30004 00000000 80000000 00020000 00000000
# DIS_NEXT: 30014 00000000 00000000 00000000 00000000
# DIS-NEXT: 30008 00000000 80000000 00000000 00000000
# DIS-NEXT: 30018 00000000 00000001 00000000 00000001
# DIS-NEXT: 30028 ffff8004 ffff9004
# DIS: 00030000 l .tdata 00000000 .tdata
# DIS: 00030000 l .tdata 00000000 loc
# DIS: 00000004 g .tdata 00000000 bar
# DIS: 00000000 g *UND* 00000000 foo
# CHECK: Relocations [
# CHECK-NEXT: Section (7) .rel.dyn {
# CHECK-NEXT: 0x30018 R_MIPS_TLS_DTPMOD32 - 0x0
# CHECK-NEXT: 0x30010 R_MIPS_TLS_DTPMOD32 foo 0x0
# CHECK-NEXT: 0x30014 R_MIPS_TLS_DTPREL32 foo 0x0
# CHECK-NEXT: 0x30020 R_MIPS_TLS_TPREL32 foo 0x0
# CHECK-NEXT: 0x30018 R_MIPS_TLS_TPREL32 foo 0x0
# CHECK-NEXT: }
# CHECK-NEXT: ]
# CHECK-NEXT: Primary GOT {
# CHECK-NEXT: Canonical gp value: 0x37FF4
# CHECK-NEXT: Canonical gp value: 0x37FF8
# CHECK-NEXT: Reserved entries [
# CHECK-NEXT: Entry {
# CHECK-NEXT: Address: 0x30004
# CHECK-NEXT: Access: -32752
# CHECK-NEXT: Initial: 0x0
# CHECK-NEXT: Purpose: Lazy resolver
# CHECK-NEXT: }
# CHECK-NEXT: Entry {
# CHECK-NEXT: Address: 0x30008
# CHECK-NEXT: Access: -32748
# CHECK-NEXT: Initial: 0x80000000
# CHECK-NEXT: Purpose: Module pointer (GNU extension)
# CHECK-NEXT: }
# CHECK-NEXT: ]
# CHECK: ]
# CHECK-NEXT: Local entries [
# CHECK-NEXT: Entry {
# CHECK-NEXT: Address: 0x3000C
# CHECK-NEXT: Access: -32744
# CHECK-NEXT: Initial: 0x20000
# CHECK-NEXT: }
# CHECK-NEXT: ]
# CHECK-NEXT: Global entries [
# CHECK-NEXT: ]
# CHECK-NEXT: Number of TLS and multi-GOT entries: 5
# ^-- 0x30010 / -32740 - R_MIPS_TLS_GD - R_MIPS_TLS_DTPMOD32 foo
# ^-- 0x30018 / -32736 - R_MIPS_TLS_DTPREL32 foo
# ^-- 0x3001C / -32732 - R_MIPS_TLS_LDM - R_MIPS_TLS_DTPMOD32 loc
# ^-- 0x30020 / -32728
# ^-- 0x30024 / -32724 - R_MIPS_TLS_GOTTPREL - R_MIPS_TLS_TPREL32
# CHECK-NEXT: Number of TLS and multi-GOT entries: 8
# ^-- 0x30010 R_MIPS_TLS_GD R_MIPS_TLS_DTPMOD32 foo
# ^-- 0x30014 R_MIPS_TLS_DTPREL32 foo
# ^-- 0x30018 R_MIPS_TLS_GOTTPREL R_MIPS_TLS_TPREL32 foo
# ^-- 0x3001C R_MIPS_TLS_LDM 1 loc
# ^-- 0x30020 0 loc
# ^-- 0x30024 R_MIPS_TLS_GD 1 bar
# ^-- 0x30028 VA - 0x8000 bar
# ^-- 0x3002C R_MIPS_TLS_GOTTPREL VA - 0x7000 bar
# DIS-SO: Contents of section .got:
# DIS-SO-NEXT: 20008 00000000 80000000 00000000 00000000
# DIS-SO-NEXT: 20018 00000000 00000000 00000000 00000000
# DIS-SO-NEXT: 20028 00000000 00000000
# SO: Relocations [
# SO-NEXT: Section (7) .rel.dyn {
# SO-NEXT: 0x2001C R_MIPS_TLS_DTPMOD32 - 0x0
# SO-NEXT: 0x20024 R_MIPS_TLS_DTPMOD32 bar 0x0
# SO-NEXT: 0x20028 R_MIPS_TLS_DTPREL32 bar 0x0
# SO-NEXT: 0x2002C R_MIPS_TLS_TPREL32 bar 0x0
# SO-NEXT: 0x20010 R_MIPS_TLS_DTPMOD32 foo 0x0
# SO-NEXT: 0x20014 R_MIPS_TLS_DTPREL32 foo 0x0
# SO-NEXT: 0x20018 R_MIPS_TLS_TPREL32 foo 0x0
# SO-NEXT: }
# SO-NEXT: ]
# SO-NEXT: Primary GOT {
# SO-NEXT: Canonical gp value: 0x27FF8
# SO-NEXT: Reserved entries [
# SO: ]
# SO-NEXT: Local entries [
# SO-NEXT: ]
# SO-NEXT: Global entries [
# SO-NEXT: ]
# SO-NEXT: Number of TLS and multi-GOT entries: 8
# ^-- 0x20010 R_MIPS_TLS_GD R_MIPS_TLS_DTPMOD32 foo
# ^-- 0x20014 R_MIPS_TLS_DTPREL32 foo
# ^-- 0x20018 R_MIPS_TLS_GOTTPREL R_MIPS_TLS_TPREL32 foo
# ^-- 0x2001C R_MIPS_TLS_LDM R_MIPS_TLS_DTPMOD32 loc
# ^-- 0x20020 0 loc
# ^-- 0x20024 R_MIPS_TLS_GD R_MIPS_TLS_DTPMOD32 bar
# ^-- 0x20028 R_MIPS_TLS_DTPREL32 bar
# ^-- 0x2002C R_MIPS_TLS_GOTTPREL R_MIPS_TLS_TPREL32 bar
.text
.global __start
__start:
addiu $2, $3, %tlsgd(foo) # R_MIPS_TLS_GD
addiu $2, $3, %tlsldm(loc) # R_MIPS_TLS_LDM
lw $2, %got(__start)($gp)
addiu $2, $3, %gottprel(foo) # R_MIPS_TLS_GOTTPREL
addiu $2, $3, %tlsldm(loc) # R_MIPS_TLS_LDM
addiu $2, $3, %tlsgd(bar) # R_MIPS_TLS_GD
addiu $2, $3, %gottprel(bar) # R_MIPS_TLS_GOTTPREL
.section .tdata,"awT",%progbits
.global bar
loc:
.word 0
bar:
.word 0