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1# This reproduces a bug with shrink wrapping when trying to move2# push-pops in a function where we are not allowed to modify the3# stack layout for alignment reasons. In this bug, we failed to4# propagate alignment requirement upwards in the call graph for5# some functions when there is a cycle in the call graph.6 7# REQUIRES: system-linux8 9# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \10# RUN: %s -o %t.o11# RUN: link_fdata %s %t.o %t.fdata12# Delete our BB symbols so BOLT doesn't mark them as entry points13# RUN: llvm-strip --strip-unneeded %t.o14# RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q15 16# RUN: llvm-bolt %t.exe --relocs=1 --frame-opt=all --print-finalized \17# RUN: --lite=0 --print-only=main --data %t.fdata -o %t.out | FileCheck %s18 19# RUN: %t.out20 21# CHECK: BOLT-INFO: Shrink wrapping moved 1 spills inserting load/stores and 0 spills inserting push/pops22 23 .text24 .globl bar25 .type bar, %function26 .p2align 427bar:28# FDATA: 0 [unknown] 0 1 bar 0 0 51029 pushq %rbp30 movq %rsp, %rbp31 pushq %rbx # We save rbx here, but there is an32 # opportunity to move it to .BB233 subq $0x18, %rsp34 cmpl $0x2, %edi35.J1:36 jb .BBend37# FDATA: 1 bar #.J1# 1 bar #.BB2# 0 1038# FDATA: 1 bar #.J1# 1 bar #.BBend# 0 50039.BB2:40 movq $2, %rbx # Use rbx in a cold block41 xorq %rax, %rax42 movb mystring, %al43 addq %rbx, %rax44 movb %al, mystring45 leaq mystring, %rdi46 #callq puts47 48.BBend:49 addq $0x18, %rsp50 pop %rbx # Restore51 xorq %rax, %rax52 cmpq $0x0, %rax53 jne .BBnever54 jmp .BBbarend55.BBnever:56 # This is a path that is never executed, but we add a call to main here57 # to force a cycle in the call graph and to require us to have an aligned58 # stack59 callq main60.BBbarend:61 leaveq62 retq63 .size bar, .-bar64 65# Frame alignedness information needs to be transmitted from foo to main to bar66 .globl main67 .type main, %function68 .p2align 469main:70 # Call a function that requires an aligned stack71 callq foo72 # Call a function that can be shrink-wrapped73 callq bar74 retq75 .size main, .-main76 77# Frame alignedness information needs to be transmitted from foo to main to bar78 .globl foo79 .type foo, %function80 .p2align 481foo:82 # Use an instruction that requires an aligned stack83 movdqa -0x10(%rsp), %xmm084 retq85 .size foo, .-foo86 87 .data88mystring: .asciz "0 is rbx mod 10 contents in decimal\n"89