xref: /llvm-project/bolt/test/runtime/X86/fix-branches-jrcxz.s (revision d648aa1b8e937de1648524e1f1016b53b29ba2a4)
16b4eb0b9SAmir Ayupov# Test BOLT does not crash by trying to change the direction of a JRCXZ
26b4eb0b9SAmir Ayupov
36b4eb0b9SAmir Ayupov# REQUIRES: system-linux
46b4eb0b9SAmir Ayupov
56b4eb0b9SAmir Ayupov# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
66b4eb0b9SAmir Ayupov# RUN:   %s -o %t.o
76b4eb0b9SAmir Ayupov# RUN: link_fdata %s %t.o %t.fdata
86b4eb0b9SAmir Ayupov# RUN: llvm-strip --strip-unneeded %t.o
9487570fbSAmir Ayupov# RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
10*d648aa1bSMaksim Panchenko# RUN: llvm-bolt %t.exe --relocs=1 --reorder-blocks=ext-tsp --print-finalized \
11*d648aa1bSMaksim Panchenko# RUN:    -o %t.out --data %t.fdata | FileCheck %s
126b4eb0b9SAmir Ayupov# RUN: %t.out 1 2 3
136b4eb0b9SAmir Ayupov
146b4eb0b9SAmir Ayupov# CHECK: BOLT-INFO
156b4eb0b9SAmir Ayupov
166b4eb0b9SAmir Ayupov  .text
176b4eb0b9SAmir Ayupov  .section .text.startup,"ax",@progbits
186b4eb0b9SAmir Ayupov  .p2align 5,,31
196b4eb0b9SAmir Ayupov  .globl main
206b4eb0b9SAmir Ayupov  .type main, %function
216b4eb0b9SAmir Ayupovmain:
226b4eb0b9SAmir Ayupov  jmp test_function
236b4eb0b9SAmir Ayupov
246b4eb0b9SAmir Ayupov.globl test_function
256b4eb0b9SAmir Ayupov.hidden test_function
266b4eb0b9SAmir Ayupov.type test_function,@function
276b4eb0b9SAmir Ayupov.align 32
286b4eb0b9SAmir Ayupovtest_function:
296b4eb0b9SAmir Ayupov# FDATA: 0 main 0 1 test_function 0 0 510
306b4eb0b9SAmir Ayupov  xorq %rcx, %rcx
316b4eb0b9SAmir Ayupov  andq $3, %rdi
326b4eb0b9SAmir Ayupov  jmpq *jumptbl(,%rdi,8)
336b4eb0b9SAmir Ayupov
346b4eb0b9SAmir Ayupov# Here are the 4 possible targets of the indirect branch to simulate a simple
356b4eb0b9SAmir Ayupov# CFG. What is important here is that BB1, the first block, conditionally
366b4eb0b9SAmir Ayupov# transfers control to the exit block with JRCXZ (.J1). We create a mock profile
376b4eb0b9SAmir Ayupov# saying that this branch is taken more often than not, causing BOLT to try to
386b4eb0b9SAmir Ayupov# put the exit block after it, which would require us to change the direction
396b4eb0b9SAmir Ayupov# of JRCXZ.
406b4eb0b9SAmir Ayupov.BB1:
416b4eb0b9SAmir Ayupov  movl $0x0, %eax
426b4eb0b9SAmir Ayupov.J1:
436b4eb0b9SAmir Ayupov  jrcxz .BBend
446b4eb0b9SAmir Ayupov# FDATA: 1 test_function #.J1# 1 test_function #.BB2# 0 10
456b4eb0b9SAmir Ayupov# FDATA: 1 test_function #.J1# 1 test_function #.BBend# 0 500
466b4eb0b9SAmir Ayupov.BB2:
476b4eb0b9SAmir Ayupov  movl $0x2, %eax
486b4eb0b9SAmir Ayupov  jmp .BBend
496b4eb0b9SAmir Ayupov.Lbb3:
506b4eb0b9SAmir Ayupov  movl $0x3, %eax
516b4eb0b9SAmir Ayupov  jmp .BBend
526b4eb0b9SAmir Ayupov.Lbb4:
536b4eb0b9SAmir Ayupov  movl $0x4, %eax
546b4eb0b9SAmir Ayupov.BBend:
556b4eb0b9SAmir Ayupov  retq
566b4eb0b9SAmir Ayupov.Lend1:
576b4eb0b9SAmir Ayupov
586b4eb0b9SAmir Ayupov  .section .rodata
596b4eb0b9SAmir Ayupov  .globl jumptbl
606b4eb0b9SAmir Ayupovjumptbl:
616b4eb0b9SAmir Ayupov  .quad .BB1
626b4eb0b9SAmir Ayupov  .quad .BB2
636b4eb0b9SAmir Ayupov  .quad .Lbb3
646b4eb0b9SAmir Ayupov  .quad .Lbb4
65