diff options
author | Vladislav Khmelevsky <och95@yandex.ru> | 2022-03-03 00:34:41 +0300 |
---|---|---|
committer | Vladislav Khmelevsky <och95@yandex.ru> | 2022-03-09 01:38:19 +0300 |
commit | 8bdbcfe7d8b0f5ab08fe4b688c3d698f38097b6b (patch) | |
tree | 5813c8f7e14ce3055167c2df7ae05548215be79e /bolt | |
parent | 16823adf2a0960d426cd551cdd87e4b8f166efd1 (diff) |
[BOLT] Handle ifuncs trampolines for aarch64
The aarch64 uses the trampolines located in .iplt section, which
contains plt-like trampolines on the value stored in .got. In this case
we don't have JUMP_SLOT relocation, but we have a symbol that belongs to
ifunc trampoline, so use it and set set plt symbol for such functions.
Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei
Differential Revision: https://reviews.llvm.org/D120850
Diffstat (limited to 'bolt')
-rw-r--r-- | bolt/include/bolt/Rewrite/RewriteInstance.h | 3 | ||||
-rw-r--r-- | bolt/lib/Rewrite/RewriteInstance.cpp | 25 | ||||
-rw-r--r-- | bolt/test/runtime/AArch64/iplt.c | 29 |
3 files changed, 49 insertions, 8 deletions
diff --git a/bolt/include/bolt/Rewrite/RewriteInstance.h b/bolt/include/bolt/Rewrite/RewriteInstance.h index d94fc9c6e709..7f39b70cbdfc 100644 --- a/bolt/include/bolt/Rewrite/RewriteInstance.h +++ b/bolt/include/bolt/Rewrite/RewriteInstance.h @@ -498,7 +498,8 @@ private: }; /// AArch64 PLT sections. - const PLTSectionInfo AArch64_PLTSections[2] = {{".plt"}, {nullptr}}; + const PLTSectionInfo AArch64_PLTSections[3] = { + {".plt"}, {".iplt"}, {nullptr}}; /// Return PLT information for a section with \p SectionName or nullptr /// if the section is not PLT. diff --git a/bolt/lib/Rewrite/RewriteInstance.cpp b/bolt/lib/Rewrite/RewriteInstance.cpp index 6c67eb3a87a2..1c5d52b227e6 100644 --- a/bolt/lib/Rewrite/RewriteInstance.cpp +++ b/bolt/lib/Rewrite/RewriteInstance.cpp @@ -1251,19 +1251,30 @@ void RewriteInstance::createPLTBinaryFunction(uint64_t TargetAddress, if (!TargetAddress) return; + auto setPLTSymbol = [&](BinaryFunction *BF, StringRef Name) { + const unsigned PtrSize = BC->AsmInfo->getCodePointerSize(); + MCSymbol *TargetSymbol = BC->registerNameAtAddress( + Name.str() + "@GOT", TargetAddress, PtrSize, PtrSize); + BF->setPLTSymbol(TargetSymbol); + }; + + BinaryFunction *BF = BC->getBinaryFunctionAtAddress(EntryAddress); + if (BF && BC->isAArch64()) { + // Handle IFUNC trampoline + setPLTSymbol(BF, BF->getOneName()); + return; + } + const Relocation *Rel = BC->getDynamicRelocationAt(TargetAddress); if (!Rel || !Rel->Symbol) return; - const unsigned PtrSize = BC->AsmInfo->getCodePointerSize(); ErrorOr<BinarySection &> Section = BC->getSectionForAddress(EntryAddress); assert(Section && "cannot get section for address"); - BinaryFunction *BF = BC->createBinaryFunction( - Rel->Symbol->getName().str() + "@PLT", *Section, EntryAddress, 0, - EntrySize, Section->getAlignment()); - MCSymbol *TargetSymbol = BC->registerNameAtAddress( - Rel->Symbol->getName().str() + "@GOT", TargetAddress, PtrSize, PtrSize); - BF->setPLTSymbol(TargetSymbol); + BF = BC->createBinaryFunction(Rel->Symbol->getName().str() + "@PLT", *Section, + EntryAddress, 0, EntrySize, + Section->getAlignment()); + setPLTSymbol(BF, Rel->Symbol->getName()); } void RewriteInstance::disassemblePLTSectionAArch64(BinarySection &Section) { diff --git a/bolt/test/runtime/AArch64/iplt.c b/bolt/test/runtime/AArch64/iplt.c new file mode 100644 index 000000000000..30a169c1265d --- /dev/null +++ b/bolt/test/runtime/AArch64/iplt.c @@ -0,0 +1,29 @@ +// This test checks that the ifuncs works after bolt. + +// RUN: %clang %cflags %s -fuse-ld=lld \ +// RUN: -o %t.exe -Wl,-q +// RUN: llvm-bolt %t.exe -o %t.bolt.exe -use-old-text=0 -lite=0 +// RUN: %t.bolt.exe | FileCheck %s + +// CHECK: foo + +#include <stdio.h> +#include <string.h> + +static void foo() { printf("foo\n"); } + +static void *resolver_foo(void) { return foo; } + +__attribute__((ifunc("resolver_foo"))) void ifoo(); + +static void *resolver_memcpy(void) { return memcpy; } + +__attribute__((ifunc("resolver_memcpy"))) void * +imemcpy(void *dest, const void *src, size_t n); + +int main() { + int a = 0xdeadbeef, b = 0; + ifoo(); + imemcpy(&b, &a, sizeof(b)); + return a != b; +} |