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1## This reproduces an issue where two fragments of same function access same2## jump table, which means at least one fragment visits the other, i.e., one3## of them has split jump table. As a result, all of them will be marked as4## non-simple function.5 6# REQUIRES: system-linux7 8# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o9# RUN: llvm-strip --strip-unneeded %t.o10# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q11# RUN: llvm-bolt -print-cfg -v=3 %t.exe -o %t.out 2>&1 | FileCheck %s12 13# CHECK: BOLT-INFO: multiple fragments access the same jump table: main; main.cold.114# CHECK: PIC Jump table JUMP_TABLE1 for function main, main.cold.1 at {{.*}} with a total count of 0:15 16 .text17 .globl main18 .type main, %function19 .p2align 220main:21LBB0:22 andl $0xf, %ecx23 cmpb $0x4, %cl24 ## exit through ret25 ja LBB326 27## jump table dispatch, jumping to label indexed by val in %ecx28LBB1:29 leaq JUMP_TABLE1(%rip), %r830 movzbl %cl, %ecx31 movslq (%r8,%rcx,4), %rax32 addq %rax, %r833 jmpq *%r834 35LBB2:36 xorq %rax, %rax37LBB3:38 addq $0x8, %rsp39 ret40.size main, .-main41 42## cold fragment is only reachable43 .globl main.cold.144 .type main.cold.1, %function45 .p2align 246main.cold.1:47 ## load bearing nop: pad LBB8 so that it can't be treated48 ## as __builtin_unreachable by analyzeJumpTable49 nop50LBB4:51 andl $0xb, %ebx52 cmpb $0x1, %cl53 # exit through ret54 ja LBB755 56## jump table dispatch, jumping to label indexed by val in %ecx57LBB5:58 leaq JUMP_TABLE1(%rip), %r859 movzbl %cl, %ecx60 movslq (%r8,%rcx,4), %rax61 addq %rax, %r862 jmpq *%r863 64LBB6:65 xorq %rax, %rax66LBB7:67 addq $0x8, %rsp68 ret69LBB8:70 callq abort71.size main.cold.1, .-main.cold.172 73 .rodata74## jmp table, entries must be R_X86_64_PC32 relocs75 .globl JUMP_TABLE176JUMP_TABLE1:77 .long LBB2-JUMP_TABLE178 .long LBB3-JUMP_TABLE179 .long LBB8-JUMP_TABLE180 .long LBB6-JUMP_TABLE181 .long LBB7-JUMP_TABLE182