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llvm-project/lld/test/ELF/linkerscript/arm-exidx-sentinel-and-assi...

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[ELF] Prevent crash in writing an .ARM.exidx sentinel entry. We might crash in 'ARMExidxSentinelSection::writeTo()' because it expected the sentinel entry to be put in the same 'InputSectionDescription' as the last real entry. This assumption fails if the last output section command for .ARM.exidx is anything but an input section description, because in this case 'OutputSection::addSection()' creates a new 'InputSectionDescription'. Differential Revision: https://reviews.llvm.org/D41105 llvm-svn: 320668
2017-12-14 14:23:50 +08:00
# REQUIRES: arm
# RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t.o
# RUN: echo "SECTIONS { \
# RUN: .ARM.exidx 0x1000 : { *(.ARM.exidx*) foo = .; } \
# RUN: .text 0x2000 : { *(.text*) } \
# RUN: }" > %t.script
## We used to crash if the last output section command for .ARM.exidx
## was anything but an input section description.
[ELF] Remove Duplicate .ARM.exidx sections The ARM.exidx section contains a table of 8-byte entries with the first word of each entry an offset to the function it describes and the second word instructions for unwinding if an exception is thrown from that function. The SHF_LINK_ORDER processing will order the table in ascending order of the functions described by the exception table entries. As the address range of an exception table entry is terminated by the next table entry, it is possible to merge consecutive table entries that have identical unwind instructions. For this implementation we define a table entry to be identical if: - Both entries are the special EXIDX_CANTUNWIND. - Both entries have the same inline unwind instructions. We do not attempt to establish if table entries that are references to .ARM.extab sections are identical. This implementation works at a granularity of a single .ARM.exidx InputSection. If all entries in the InputSection are identical to the previous table entry we can remove the InputSection. A more sophisticated but more complex implementation would rewrite InputSection contents so that duplicates within a .ARM.exidx InputSection can be merged. Differential Revision: https://reviews.llvm.org/D40967 llvm-svn: 320803
2017-12-15 19:09:41 +08:00
# RUN: ld.lld --no-merge-exidx-entries -T %t.script %t.o -shared -o %t.so
[test] lld/test/: change llvm-objdump single-dash long options to double-dash options
2020-03-16 08:47:44 +08:00
# RUN: llvm-objdump -s --triple=armv7a-none-linux-gnueabi %t.so | FileCheck %s
[test] Change llvm-readobj -long-option to --long-option or well-known short options. NFC Also change some options that have different semantics (cause confusion) in llvm-readelf mode: -s => -S -t => --symbols -sd => --section-data llvm-svn: 359651
2019-05-01 13:49:01 +08:00
# RUN: llvm-readobj -S --symbols %t.so | FileCheck %s --check-prefix=SYMBOL
[ELF] Prevent crash in writing an .ARM.exidx sentinel entry. We might crash in 'ARMExidxSentinelSection::writeTo()' because it expected the sentinel entry to be put in the same 'InputSectionDescription' as the last real entry. This assumption fails if the last output section command for .ARM.exidx is anything but an input section description, because in this case 'OutputSection::addSection()' creates a new 'InputSectionDescription'. Differential Revision: https://reviews.llvm.org/D41105 llvm-svn: 320668
2017-12-14 14:23:50 +08:00
.syntax unified
.text
.global _start
_start:
.fnstart
.cantunwind
bx lr
.fnend
Use # instead of // for comments in a test. The test was using both // and # before. llvm-svn: 321049
2017-12-19 08:53:06 +08:00
# CHECK: Contents of section .ARM.exidx:
# 1000 + 1000 = 0x2000 = _start
# 1008 + 0ffc = 0x2004 = _start + sizeof(_start)
# CHECK-NEXT: 1000 00100000 01000000 fc0f0000 01000000
[ELF] Fix an assignment command at the end of an .ARM.exidx section. The value of the symbol in the assignment should include the sentinel entry. Differential Revision: https://reviews.llvm.org/D41234 llvm-svn: 321154
2017-12-20 16:56:10 +08:00
# SYMBOL: Section {
# SYMBOL: Name: .ARM.exidx
# SYMBOL-NEXT: Type: SHT_ARM_EXIDX
# SYMBOL-NEXT: Flags [
# SYMBOL-NEXT: SHF_ALLOC
# SYMBOL-NEXT: SHF_LINK_ORDER
# SYMBOL-NEXT: ]
# SYMBOL-NEXT: Address: 0x1000
# SYMBOL-NEXT: Offset:
# SYMBOL-NEXT: Size: 16
# Symbol 'foo' is expected to point at the end of the section.
# SYMBOL: Symbol {
# SYMBOL: Name: foo
# SYMBOL-NEXT: Value: 0x1010