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1## This reproduces an issue where the function is split into three fragments2## and all fragments access the same jump table.3 4# REQUIRES: system-linux5 6# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o7# RUN: llvm-strip --strip-unneeded %t.o8# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q9# RUN: llvm-bolt %t.exe -o %t.out -v=1 -print-only=main.warm -print-cfg 2>&1 | FileCheck %s10 11# CHECK-DAG: BOLT-INFO: marking main.warm as a fragment of main12# CHECK-DAG: BOLT-INFO: marking main.cold as a fragment of main13# CHECK-DAG: BOLT-INFO: processing main.warm as a sibling of non-ignored function14# CHECK-DAG: BOLT-INFO: processing main.cold as a sibling of non-ignored function15# CHECK-DAG: BOLT-WARNING: Ignoring main.cold16# CHECK-DAG: BOLT-WARNING: Ignoring main.warm17# CHECK-DAG: BOLT-WARNING: Ignoring main18# CHECK: BOLT-WARNING: skipped 3 functions due to cold fragments19 20# CHECK: PIC Jump table JUMP_TABLE for function main, main.warm, main.cold21# CHECK-NEXT: 0x0000 : __ENTRY_main@0x[[#]]22# CHECK-NEXT: 0x0004 : __ENTRY_main@0x[[#]]23# CHECK-NEXT: 0x0008 : __ENTRY_main.cold@0x[[#]]24# CHECK-NEXT: 0x000c : __ENTRY_main@0x[[#]]25 .globl main26 .type main, %function27 .p2align 228main:29LBB0:30 andl $0xf, %ecx31 cmpb $0x4, %cl32 ## exit through ret33 ja LBB334 35## jump table dispatch, jumping to label indexed by val in %ecx36LBB1:37 leaq JUMP_TABLE(%rip), %r838 movzbl %cl, %ecx39 movslq (%r8,%rcx,4), %rax40 addq %rax, %r841 jmpq *%r842 43LBB2:44 xorq %rax, %rax45LBB3:46 addq $0x8, %rsp47 ret48.size main, .-main49 50 .globl main.warm51 .type main.warm, %function52 .p2align 253main.warm:54LBB20:55 andl $0xb, %ebx56 cmpb $0x1, %cl57 # exit through ret58 ja LBB2359 60## jump table dispatch, jumping to label indexed by val in %ecx61LBB21:62 leaq JUMP_TABLE(%rip), %r863 movzbl %cl, %ecx64 movslq (%r8,%rcx,4), %rax65 addq %rax, %r866 jmpq *%r867 68LBB22:69 xorq %rax, %rax70LBB23:71 addq $0x8, %rsp72 ret73.size main.warm, .-main.warm74 75## cold fragment is only reachable through jump table76 .globl main.cold77 .type main.cold, %function78main.cold:79 leaq JUMP_TABLE(%rip), %r880 movzbl %cl, %ecx81 movslq (%r8,%rcx,4), %rax82 addq %rax, %r883 jmpq *%r884LBB4:85 callq abort86.size main.cold, .-main.cold87 88 .rodata89## jmp table, entries must be R_X86_64_PC32 relocs90 .globl JUMP_TABLE91JUMP_TABLE:92 .long LBB2-JUMP_TABLE93 .long LBB3-JUMP_TABLE94 .long LBB4-JUMP_TABLE95 .long LBB3-JUMP_TABLE96