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1## This reproduces a bug with jump table identification where jump table has2## entries pointing to code in function and its cold fragment.3## The fragment is only reachable through jump table.4 5# REQUIRES: system-linux6 7# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o8# RUN: llvm-strip --strip-unneeded %t.o9# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q10# RUN: llvm-bolt %t.exe -o %t.out --lite=0 -v=1 2>&1 | FileCheck %s11 12# CHECK-NOT: unclaimed PC-relative relocations left in data13# CHECK: BOLT-INFO: marking main.cold.1 as a fragment of main14 .text15 .globl main16 .type main, %function17 .p2align 218main:19LBB0:20 andl $0xf, %ecx21 cmpb $0x4, %cl22 ## exit through ret23 ja LBB324 25## jump table dispatch, jumping to label indexed by val in %ecx26LBB1:27 leaq JUMP_TABLE(%rip), %r828 movzbl %cl, %ecx29 movslq (%r8,%rcx,4), %rax30 addq %rax, %r831 jmpq *%r832 33LBB2:34 xorq %rax, %rax35LBB3:36 addq $0x8, %rsp37 ret38.size main, .-main39 40## cold fragment is only reachable through jump table41 .globl main.cold.142 .type main.cold.1, %function43 .p2align 244main.cold.1:45 ## load bearing nop: pad LBB4 so that it can't be treated46 ## as __builtin_unreachable by analyzeJumpTable47 nop48LBB4:49 callq abort50.size main.cold.1, .-main.cold.151 52 .rodata53## jmp table, entries must be R_X86_64_PC32 relocs54 .globl JUMP_TABLE55JUMP_TABLE:56 .long LBB2-JUMP_TABLE57 .long LBB3-JUMP_TABLE58 .long LBB4-JUMP_TABLE59 .long LBB3-JUMP_TABLE60