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# This reproduces a bug with jump table identification where jump table has
# entries pointing to code in function and its cold fragment.
# The fragment is only reachable through jump table.
# REQUIRES: system-linux
# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o
# RUN: llvm-strip --strip-unneeded %t.o
# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q
# RUN: llvm-bolt %t.exe -o %t.out -lite=0 -v=1 2>&1 | FileCheck %s
# CHECK-NOT: unclaimed PC-relative relocations left in data
# CHECK: BOLT-INFO: marking main.cold as a fragment of main
.text
.globl _start
.type _start, %function
_start:
callq main.cold
call exit
.size _start, .-_start
.globl main.cold
.type main.cold, %function
.p2align 2
main.cold:
LBB0:
andl $0xf, %ecx
cmpb $0x4, %cl
# exit through ret
ja LBB3
# jump table dispatch, jumping to label indexed by val in %ecx
LBB1:
leaq JUMP_TABLE(%rip), %r8
movzbl %cl, %ecx
movslq (%r8,%rcx,4), %rax
addq %rax, %r8
jmpq *%r8
LBB2:
xorq %rax, %rax
LBB3:
addq $0x8, %rsp
ret
.size main.cold, .-main.cold
# main function, referenced from jump table in cold fragment
.globl main
.type main, %function
.p2align 2
main:
# load bearing nop: pad LBB4 so that it can't be treated
# as __builtin_unreachable by analyzeJumpTable
nop
LBB4:
callq abort
.size main, .-main
.rodata
# jmp table, entries must be R_X86_64_PC32 relocs
.globl JUMP_TABLE
JUMP_TABLE:
.long LBB2-JUMP_TABLE
.long LBB3-JUMP_TABLE
.long LBB4-JUMP_TABLE
.long LBB3-JUMP_TABLE
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