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# This reproduces an issue where two cold fragments are folded into one, so the
# fragment has two parents.
# The fragment is only reachable through a jump table, so all functions must be
# ignored.
# 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 -v=1 --print-only=main2.cold.1 --print-disasm 2>&1 | FileCheck %s
# CHECK-NOT: unclaimed PC-relative relocations left in data
# CHECK-DAG: BOLT-INFO: marking main2.cold.1(*2) as a fragment of main2
# CHECK-DAG: BOLT-INFO: marking main2.cold.1(*2) as a fragment of main
# CHECK: Binary Function "main2.cold.1(*2)" after disassembly
# CHECK: End of Function "main2.cold.1(*2)"
# CHECK-DAG: BOLT-WARNING: Ignoring main2
# CHECK-DAG: BOLT-WARNING: Ignoring main
# CHECK-DAG: BOLT-WARNING: Ignoring main2.cold.1(*2)
# CHECK: BOLT-WARNING: skipped 3 functions due to cold fragments
.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
.globl main2
.type main2, %function
.p2align 2
main2:
LBB20:
andl $0xb, %ebx
cmpb $0x1, %cl
# exit through ret
ja LBB23
# jump table dispatch, jumping to label indexed by val in %ecx
LBB21:
leaq JUMP_TABLE2(%rip), %r8
movzbl %cl, %ecx
movslq (%r8,%rcx,4), %rax
addq %rax, %r8
jmpq *%r8
LBB22:
xorq %rax, %rax
LBB23:
addq $0x8, %rsp
ret
.size main2, .-main2
# cold fragment is only reachable through jump table
.globl main2.cold.1
.type main2.cold.1, %function
main2.cold.1:
.globl main.cold.1
.type main.cold.1, %function
.p2align 2
main.cold.1:
# load bearing nop: pad LBB4 so that it can't be treated
# as __builtin_unreachable by analyzeJumpTable
nop
LBB4:
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 LBB4-JUMP_TABLE1
.long LBB3-JUMP_TABLE1
.globl JUMP_TABLE2
JUMP_TABLE2:
.long LBB22-JUMP_TABLE2
.long LBB23-JUMP_TABLE2
.long LBB4-JUMP_TABLE2
.long LBB23-JUMP_TABLE2
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