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# This reproduces an issue where two fragments of same function access same
# jump table, which means at least one fragment visits the other, i.e., one
# of them has split jump table. As a result, all of them will be marked as
# non-simple function.
# 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 -print-cfg -v=3 %t.exe -o %t.out 2>&1 | FileCheck %s
# CHECK: BOLT-INFO: Multiple fragments access same jump table: main; main.cold.1
# CHECK: PIC Jump table JUMP_TABLE1 for function main, main.cold.1 at {{.*}} with a total count of 0:
.text
.globl main
.type main, %function
.p2align 2
main:
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_TABLE1(%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, .-main
# cold fragment is only reachable
.globl main.cold.1
.type main.cold.1, %function
.p2align 2
main.cold.1:
# load bearing nop: pad LBB8 so that it can't be treated
# as __builtin_unreachable by analyzeJumpTable
nop
LBB4:
andl $0xb, %ebx
cmpb $0x1, %cl
# exit through ret
ja LBB7
# jump table dispatch, jumping to label indexed by val in %ecx
LBB5:
leaq JUMP_TABLE1(%rip), %r8
movzbl %cl, %ecx
movslq (%r8,%rcx,4), %rax
addq %rax, %r8
jmpq *%r8
LBB6:
xorq %rax, %rax
LBB7:
addq $0x8, %rsp
ret
LBB8:
callq abort
.size main.cold.1, .-main.cold.1
.rodata
# jmp table, entries must be R_X86_64_PC32 relocs
.globl JUMP_TABLE1
JUMP_TABLE1:
.long LBB2-JUMP_TABLE1
.long LBB3-JUMP_TABLE1
.long LBB8-JUMP_TABLE1
.long LBB6-JUMP_TABLE1
.long LBB7-JUMP_TABLE1
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