mirror of
https://github.com/llvm/llvm-project.git
synced 2025-04-26 05:36:07 +00:00
7de82ca369
Under normal circumstances, we terminate basic blocks on a trap instruction. However, Linux kernel may resume execution after hitting a trap (ud2 on x86). Thus, we introduce "--terminal-trap" option that will specify if the trap instruction should terminate the control flow. The option is on by default except for the Linux kernel mode when it's off.
62 lines
1.5 KiB
ArmAsm
62 lines
1.5 KiB
ArmAsm
# REQUIRES: system-linux
|
|
|
|
## Check that BOLT correctly parses and updates the Linux kernel __bug_table
|
|
## section.
|
|
|
|
# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o
|
|
# RUN: %clang %cflags -nostdlib %t.o -o %t.exe \
|
|
# RUN: -Wl,--image-base=0xffffffff80000000,--no-dynamic-linker,--no-eh-frame-hdr,--no-pie
|
|
|
|
## Verify bug entry bindings to instructions.
|
|
|
|
# RUN: llvm-bolt %t.exe --print-normalized --print-only=_start -o %t.out \
|
|
# RUN: --eliminate-unreachable=1 --bolt-info=0 | FileCheck %s
|
|
|
|
## Verify bug entry bindings again after unreachable code elimination.
|
|
|
|
# RUN: llvm-bolt %t.out -o %t.out.1 --print-only=_start --print-normalized \
|
|
# RUN: |& FileCheck --check-prefix=CHECK-REOPT %s
|
|
|
|
# CHECK: BOLT-INFO: Linux kernel binary detected
|
|
# CHECK: BOLT-INFO: parsed 2 bug table entries
|
|
|
|
.text
|
|
.globl _start
|
|
.type _start, %function
|
|
_start:
|
|
jmp .L1
|
|
.L0:
|
|
ud2
|
|
# CHECK: ud2
|
|
# CHECK-SAME: BugEntry: 1
|
|
.L1:
|
|
ud2
|
|
# CHECK: ud2
|
|
# CHECK-SAME: BugEntry: 2
|
|
|
|
## Only the second entry should remain after the first pass.
|
|
|
|
# CHECK-REOPT: ud2
|
|
# CHECK-REOPT-SAME: BugEntry: 2
|
|
|
|
ret
|
|
## The return instruction is reachable only via preceding ud2. Test that it is
|
|
## treated as a reachable instruction in the Linux kernel mode.
|
|
|
|
# CHECK-REOPT-NEXT: ret
|
|
.size _start, .-_start
|
|
|
|
|
|
## Bug table.
|
|
.section __bug_table,"a",@progbits
|
|
1:
|
|
.long .L0 - . # instruction
|
|
.org 1b + 12
|
|
2:
|
|
.long .L1 - . # instruction
|
|
.org 2b + 12
|
|
|
|
## Fake Linux Kernel sections.
|
|
.section __ksymtab,"a",@progbits
|
|
.section __ksymtab_gpl,"a",@progbits
|