[ARM] ARM TLS shouldn't use relaxations
The ARM TLS relocations are placed on literal data and not the
code-sequence, it is therefore not possible to implement the relaxTls*
functions. This change updates handleMipsTlsRelocation() to
handleNoRelaxTlsRelocation() and incorporates ARM as well as Mips.
The ARM support in handleNoRelaxTlsRelocation() currently needs to ouput
the module index dynamic relocation in all cases as it is relying on the
dynamic linker to set the module index in the got.
Should address PR30218
Differential Revision: https://reviews.llvm.org/D24827
llvm-svn: 282250
diff --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp
index 2dce30a..61fb1dd 100644
--- a/lld/ELF/Relocations.cpp
+++ b/lld/ELF/Relocations.cpp
@@ -83,32 +83,40 @@
return Body.isPreemptible();
}
-// This function is similar to the `handleTlsRelocation`. MIPS does not support
-// any relaxations for TLS relocations so by factoring out MIPS handling into
-// the separate function we can simplify the code and does not pollute
-// `handleTlsRelocation` by MIPS `ifs` statements.
+// This function is similar to the `handleTlsRelocation`. ARM and MIPS do not
+// support any relaxations for TLS relocations so by factoring out ARM and MIPS
+// handling in to the separate function we can simplify the code and do not
+// pollute `handleTlsRelocation` by ARM and MIPS `ifs` statements.
+// FIXME: The ARM implementation always adds the module index dynamic
+// relocation even for non-preemptible symbols in applications. For static
+// linking support we must either resolve the module index relocation at static
+// link time, or hard code the module index (1) for the application in the GOT.
template <class ELFT>
-static unsigned
-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() && Config->Pic)
+static unsigned handleNoRelaxTlsRelocation(uint32_t Type, SymbolBody &Body,
+ InputSectionBase<ELFT> &C,
+ typename ELFT::uint Offset,
+ typename ELFT::uint Addend,
+ RelExpr Expr) {
+ if (Expr == R_MIPS_TLSLD || Expr == R_TLSLD_PC) {
+ if (Out<ELFT>::Got->addTlsIndex() &&
+ (Config->Pic || Config->EMachine == EM_ARM))
Out<ELFT>::RelaDyn->addReloc({Target->TlsModuleIndexRel, Out<ELFT>::Got,
Out<ELFT>::Got->getTlsIndexOff(), false,
nullptr, 0});
C.Relocations.push_back({Expr, Type, Offset, Addend, &Body});
return 1;
}
+ typedef typename ELFT::uint uintX_t;
if (Target->isTlsGlobalDynamicRel(Type)) {
- if (Out<ELFT>::Got->addDynTlsEntry(Body) && Body.isPreemptible()) {
- typedef typename ELFT::uint uintX_t;
+ if (Out<ELFT>::Got->addDynTlsEntry(Body) &&
+ (Body.isPreemptible() || Config->EMachine == EM_ARM)) {
uintX_t Off = Out<ELFT>::Got->getGlobalDynOffset(Body);
Out<ELFT>::RelaDyn->addReloc(
{Target->TlsModuleIndexRel, Out<ELFT>::Got, Off, false, &Body, 0});
- Out<ELFT>::RelaDyn->addReloc({Target->TlsOffsetRel, Out<ELFT>::Got,
- Off + (uintX_t)sizeof(uintX_t), false,
- &Body, 0});
+ if (Body.isPreemptible())
+ Out<ELFT>::RelaDyn->addReloc({Target->TlsOffsetRel, Out<ELFT>::Got,
+ Off + (uintX_t)sizeof(uintX_t), false,
+ &Body, 0});
}
C.Relocations.push_back({Expr, Type, Offset, Addend, &Body});
return 1;
@@ -130,8 +138,9 @@
typedef typename ELFT::uint uintX_t;
- if (Config->EMachine == EM_MIPS)
- return handleMipsTlsRelocation<ELFT>(Type, Body, C, Offset, Addend, Expr);
+ if (Config->EMachine == EM_MIPS || Config->EMachine == EM_ARM)
+ return handleNoRelaxTlsRelocation<ELFT>(Type, Body, C, Offset, Addend,
+ Expr);
if ((Expr == R_TLSDESC || Expr == R_TLSDESC_PAGE || Expr == R_HINT) &&
Config->Shared) {