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llvm-project/lld/test/ELF/ppc32-reloc-addr.s

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[PPC32] Improve the 32-bit PowerPC port Many -static/-no-pie/-shared/-pie applications linked against glibc or musl should work with this patch. This also helps FreeBSD PowerPC64 to migrate their lib32 (PR40888). * Fix default image base and max page size. * Support new-style Secure PLT (see below). Old-style BSS PLT is not implemented, so it is not suitable for FreeBSD rtld now because it doesn't support Secure PLT yet. * Support more initial relocation types: R_PPC_ADDR32, R_PPC_REL16*, R_PPC_LOCAL24PC, R_PPC_PLTREL24, and R_PPC_GOT16. The addend of R_PPC_PLTREL24 is special: it decides the call stub PLT type but it should be ignored for the computation of target symbol VA. * Support GNU ifunc * Support .glink used for lazy PLT resolution in glibc * Add a new thunk type: PPC32PltCallStub that is similar to PPC64PltCallStub. It is used by R_PPC_REL24 and R_PPC_PLTREL24. A PLT stub used in -fPIE/-fPIC usually loads an address relative to .got2+0x8000 (-fpie/-fpic code uses _GLOBAL_OFFSET_TABLE_ relative addresses). Two .got2 sections in two object files have different addresses, thus a PLT stub can't be shared by two object files. To handle this incompatibility, change the parameters of Thunk::isCompatibleWith to `const InputSection &, const Relocation &`. PowerPC psABI specified an old-style .plt (BSS PLT) that is both writable and executable. Linkers don't make separate RW- and RWE segments, which causes all initially writable memory (think .data) executable. This is a big security concern so a new PLT scheme (secure PLT) was developed to address the security issue. TLS will be implemented in D62940. glibc older than ~2012 requires .rela.dyn to include .rela.plt, it can not handle the DT_RELA+DT_RELASZ == DT_JMPREL case correctly. A hack (not included in this patch) in LinkerScript.cpp addOrphanSections() to work around the issue: if (Config->EMachine == EM_PPC) { // Older glibc assumes .rela.dyn includes .rela.plt Add(In.RelaDyn); if (In.RelaPlt->isLive() && !In.RelaPlt->Parent) In.RelaDyn->getParent()->addSection(In.RelaPlt); } Reviewed By: ruiu Differential Revision: https://reviews.llvm.org/D62464 llvm-svn: 362721
2019-06-07 01:03:00 +08:00
# REQUIRES: ppc
# RUN: llvm-mc -filetype=obj -triple=powerpc %s -o %t.o
# RUN: ld.lld --noinhibit-exec %t.o --defsym=a=0x1234 --defsym=b=0xbcdef -o %t 2>&1 | \
# RUN: FileCheck --check-prefix=WARN %s
# RUN: llvm-objdump -d --no-show-raw-insn %t | FileCheck %s
# RUN: llvm-objdump -s --no-show-raw-insn %t | FileCheck --check-prefix=HEX %s
.section .R_PPC_ADDR16,"ax",@progbits
lis 4, a
lis 4, b
# CHECK-LABEL: section .R_PPC_ADDR16:
# CHECK: lis 4, 4660
# WARN: warning: {{.*}}.o:(.R_PPC_ADDR16+0x6): relocation R_PPC_ADDR16 out of range: 773615 is not in [-32768, 32767]
.section .R_PPC_ADDR16_HA,"ax",@progbits
lis 4, a@ha
# CHECK-LABEL: section .R_PPC_ADDR16_HA:
# CHECK: lis 4, 0
.section .R_PPC_ADDR16_HI,"ax",@progbits
lis 4, a@h
# CHECK-LABEL: section .R_PPC_ADDR16_HI:
# CHECK: lis 4, 0
.section .R_PPC_ADDR16_LO,"ax",@progbits
addi 4, 4, a@l
# CHECK-LABEL: section .R_PPC_ADDR16_LO:
# CHECK: addi 4, 4, 4660
.section .R_PPC_ADDR32,"a",@progbits
.long a
.long b
# HEX-LABEL: section .R_PPC_ADDR32:
# HEX-NEXT: 100000b4 00001234 000bcdef