Magic-Mirror/llvm-capstone
1
0
Fork 0
mirror of https://github.com/capstone-engine/llvm-capstone.git synced 2024-11-23 22:00:10 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

[PowerPC][LLD] Make sure that the correct Thunks are used.

Browse Source 
This fixes an issue where mixed TOC / NOTOC calls can call the incorrect
thunks if a previous thunk already exists. The issue appears when a TOC
funciton calls a NOTOC callee and then a different NOTOC function calls the same
NOTOC callee. In this case the linker would sometimes incorrectly call the
same thunk for both cases.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D101837
This commit is contained in:
Stefan Pintilie 2021-05-04 09:35:43 -05:00
parent 6660319cef
commit f0adf3a24c
2 changed files with 154 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
lld/ELF/Thunks.cpp
View File

@ -312,6 +312,8 @@ public:
uint32_t size() override { return getMayUseShortThunk() ? 8 : 32; }
void writeTo(uint8_t *buf) override;
void addSymbols(ThunkSection &isec) override;
bool isCompatibleWith(const InputSection &isec,
const Relocation &rel) const override;
private:
// Transitioning from long to short can create layout oscillations in
@ -333,6 +335,8 @@ public:
uint32_t size() override { return 32; }
void writeTo(uint8_t *buf) override;
void addSymbols(ThunkSection &isec) override;
bool isCompatibleWith(const InputSection &isec,
const Relocation &rel) const override;
};
// PPC64 PC-relative PLT Stub
@ -965,6 +969,11 @@ void PPC64R2SaveStub::addSymbols(ThunkSection &isec) {
s->needsTocRestore = true;
}
bool PPC64R2SaveStub::isCompatibleWith(const InputSection &isec,
const Relocation &rel) const {
return rel.type == R_PPC64_REL24 || rel.type == R_PPC64_REL14;
}
void PPC64R12SetupStub::writeTo(uint8_t *buf) {
int64_t offset = destination.getVA() - getThunkTargetSym()->getVA();
if (!isInt<34>(offset))
@ -995,6 +1004,11 @@ void PPC64R12SetupStub::addSymbols(ThunkSection &isec) {
isec);
}
bool PPC64R12SetupStub::isCompatibleWith(const InputSection &isec,
const Relocation &rel) const {
return rel.type == R_PPC64_REL24_NOTOC;
}
void PPC64PCRelPLTStub::writeTo(uint8_t *buf) {
int nextInstOffset = 0;
int64_t offset = destination.getGotPltVA() - getThunkTargetSym()->getVA();

140
lld/test/ELF/ppc64-pcrel-cross-link.s Normal file
View File

@ -0,0 +1,140 @@
# REQUIRES: ppc
# RUN: split-file %s %t
# RUN: llvm-mc -filetype=obj -triple=powerpc64le %t/callees.s -o %t-callees.o
# RUN: llvm-mc -filetype=obj -triple=powerpc64le %t/callertoc.s -o %t-callertoc.o
# RUN: llvm-mc -filetype=obj -triple=powerpc64le %t/callernotoc.s -o %t-callernotoc.o
# RUN: ld.lld -T %t/lds %t-callees.o %t-callernotoc.o %t-callertoc.o -o %t-r12setup
# RUN: ld.lld -T %t/ldsswap %t-callees.o %t-callernotoc.o %t-callertoc.o -o %t-r2save
# RUN: llvm-objdump -d --no-show-raw-insn --mcpu=pwr10 %t-r12setup | \
# RUN: FileCheck %s --check-prefix=NOSWAP
# RUN: llvm-objdump -d --no-show-raw-insn --mcpu=pwr10 %t-r2save | \
# RUN: FileCheck %s --check-prefix=SWAP
## This test checks that it is possible to mix TOC and NOTOC functions and have
## the correct thunks for all of the calls.
# NOSWAP-LABEL: 01001000 <func>:
# NOSWAP-NEXT: blr
# NOSWAP-LABEL: 01002000 <callee_toc>:
# NOSWAP: bl 0x1001000
# NOSWAP: blr
# NOSWAP-LABEL: 01002018 <callee_notoc>:
# NOSWAP: bl 0x1001000
# NOSWAP: blr
# NOSWAP-LABEL: 10030000 <caller_notoc>:
# NOSWAP-NEXT: bl 0x10030010
# NOSWAP-NEXT: bl 0x10030030
# NOSWAP-NEXT: blr
# NOSWAP-LABEL: 10030010 <__gep_setup_callee_toc>:
# NOSWAP: bctr
# NOSWAP-LABEL: 10030030 <__long_branch_pcrel_callee_notoc>:
# NOSWAP: bctr
# NOSWAP-LABEL: 10040000 <caller_toc>:
# NOSWAP: bl 0x10040020
# NOSWAP-NEXT: nop
# NOSWAP-NEXT: bl 0x10040040
# NOSWAP-NEXT: ld 2, 24(1)
# NOSWAP-NEXT: blr
# NOSWAP-LABEL: 10040020 <__long_branch_callee_toc>:
# NOSWAP: bctr
# NOSWAP-LABEL: 10040040 <__toc_save_callee_notoc>:
# NOSWAP-NEXT: std 2, 24(1)
# NOSWAP: bctr
# SWAP-LABEL: 01001000 <func>:
# SWAP-NEXT: blr
# SWAP-LABEL: 01002000 <callee_toc>:
# SWAP: bl 0x1001000
# SWAP: blr
# SWAP-LABEL: 01002018 <callee_notoc>:
# SWAP: bl 0x1001000
# SWAP: blr
# SWAP-LABEL: 10030000 <caller_toc>:
# SWAP: bl 0x10030020
# SWAP-NEXT: nop
# SWAP-NEXT: bl 0x10030040
# SWAP-NEXT: ld 2, 24(1)
# SWAP-NEXT: blr
# SWAP-LABEL: 10030020 <__long_branch_callee_toc>:
# SWAP: bctr
# SWAP-LABEL: 10030040 <__toc_save_callee_notoc>:
# SWAP-NEXT: std 2, 24(1)
# SWAP: bctr
# SWAP-LABEL: 10040000 <caller_notoc>:
# SWAP-NEXT: bl 0x10040010
# SWAP-NEXT: bl 0x10040030
# SWAP-NEXT: blr
# SWAP-LABEL: 10040010 <__gep_setup_callee_toc>:
# SWAP: bctr
# SWAP-LABEL: 10040030 <__long_branch_pcrel_callee_notoc>:
# SWAP: bctr
#--- lds
SECTIONS {
.text_func 0x1001000 : { *(.text_func) }
.text_callee 0x1002000 : { *(.text_callee) }
.text_caller_notoc 0x10030000 : { *(.text_caller_notoc) }
.text_caller_toc 0x10040000 : { *(.text_caller_toc) }
}
#--- ldsswap
SECTIONS {
.text_func 0x1001000 : { *(.text_func) }
.text_callee 0x1002000 : { *(.text_callee) }
.text_caller_toc 0x10030000 : { *(.text_caller_toc) }
.text_caller_notoc 0x10040000 : { *(.text_caller_notoc) }
}
#--- callees.s
.section .text_func, "ax", %progbits
func:
blr
.globl callee_toc
.section .text_callee, "ax", %progbits
callee_toc:
.Lfunc_gep1:
addis 2, 12, .TOC.-.Lfunc_gep1@ha
addi 2, 2, .TOC.-.Lfunc_gep1@l
.Lfunc_lep1:
.localentry callee_toc, .Lfunc_lep1-.Lfunc_gep1
bl func
addis 4, 2, global@toc@ha
lwz 4, global@toc@l(4)
blr
.globl callee_notoc
callee_notoc:
.localentry callee_notoc, 1
bl func
plwz 4, global@pcrel(0), 1
blr
## .globl global
global:
.long 0
.size global, 4
#--- callernotoc.s
.section .text_caller_notoc, "ax", %progbits
caller_notoc:
.localentry caller, 1
bl callee_toc@notoc
bl callee_notoc@notoc
blr
#--- callertoc.s
.section .text_caller_toc, "ax", %progbits
caller_toc:
.Lfunc_gep2:
addis 2, 12, .TOC.-.Lfunc_gep2@ha
addi 2, 2, .TOC.-.Lfunc_gep2@l
.Lfunc_lep2:
.localentry caller_toc, .Lfunc_lep2-.Lfunc_gep2
bl callee_toc
nop
bl callee_notoc
nop
blr