xref: /llvm-project/bolt/test/runtime/X86/shrinkwrapping-pushpop.s (revision d648aa1b8e937de1648524e1f1016b53b29ba2a4)
1# This reproduces a bug with shrink wrapping when trying to move
2# push-pops where restores were not validated to be POPs (and could be
3# a regular load, which violated our assumptions). Check that we
4# identify those cases.
5
6# REQUIRES: system-linux
7
8# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
9# RUN:   %s -o %t.o
10# RUN: link_fdata %s %t.o %t.fdata
11# Delete our BB symbols so BOLT doesn't mark them as entry points
12# RUN: llvm-strip --strip-unneeded %t.o
13# RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
14
15# RUN: llvm-bolt %t.exe --relocs=1 --frame-opt=all --print-finalized \
16# RUN:    --print-only=main --data %t.fdata -o %t.out | FileCheck %s
17
18# RUN: %t.out
19
20# CHECK: BOLT-INFO: Shrink wrapping moved 1 spills inserting load/stores and 0 spills inserting push/pops
21
22  .text
23  .globl  main
24  .type main, %function
25  .p2align  4
26main:
27# FDATA: 0 [unknown] 0 1 main 0 0 510
28  pushq %rbp
29  movq  %rsp, %rbp
30  pushq %rbx                  # We save rbx here, but there is an
31                              # opportunity to move it to .LBB2
32  subq  $0x18, %rsp
33  cmpl  $0x2, %edi
34.J1:
35  jb    .BBend
36# FDATA: 1 main #.J1# 1 main #.BB2# 0 10
37# FDATA: 1 main #.J1# 1 main #.BBend# 0 500
38.BB2:
39  movq $2, %rbx               # Use rbx in a cold block
40  xorq %rax, %rax
41  movb mystring, %al
42  addq %rbx, %rax
43  movb %al, mystring
44  leaq mystring, %rdi
45# Avoid making the actual call here to allow push-pop mode to operate
46# without fear of an unknown function that may require aligned stack
47#  callq puts
48
49.BBend:
50  mov -0x08(%rbp), %rbx       # Original restore is here. Instead of a pop
51                              # we use a load to reproduce gcc behavior while
52                              # using leave in epilogue. Ordinarily it would
53                              # addq $0x18, %rsp followed by pop %rbx
54  xorq %rax, %rax
55  leaveq
56  retq
57  .size main, .-main
58
59  .data
60mystring: .asciz "0 is rbx mod 10 contents in decimal\n"
61