1## This checks that shrink wrapping does attempt at accessing stack elements 2## using RSP when the function is aligning RSP and changing offsets. 3 4# REQUIRES: system-linux 5 6# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \ 7# RUN: %s -o %t.o 8# RUN: link_fdata %s %t.o %t.fdata 9# RUN: llvm-strip --strip-unneeded %t.o 10# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q -nostdlib 11# RUN: llvm-bolt %t.exe -o %t.out --data %t.fdata \ 12# RUN: --frame-opt=all --simplify-conditional-tail-calls=false \ 13# RUN: --eliminate-unreachable=false | FileCheck %s 14 15## Here we have a function that aligns the stack at prologue. Stack pointer 16## analysis can't try to infer offset positions after AND because that depends 17## on the runtime value of the stack pointer of callee (whether it is misaligned 18## or not). 19 .globl _start 20 .type _start, %function 21_start: 22 .cfi_startproc 23# FDATA: 0 [unknown] 0 1 _start 0 0 1 24 push %rbp 25 mov %rsp, %rbp 26 push %rbx 27 push %r14 28 and $0xffffffffffffffe0,%rsp 29 subq $0x20, %rsp 30b: je hot_path 31# FDATA: 1 _start #b# 1 _start #hot_path# 0 1 32cold_path: 33 mov %r14, %rdi 34 mov %rbx, %rdi 35 # Block push-pop mode by using an instruction that requires the 36 # stack to be aligned to 128B. This will force the pass 37 # to try to index stack elements by using RSP +offset directly, but 38 # we do not know how to access individual elements of the stack thanks 39 # to the alignment. 40 movdqa %xmm8, (%rsp) 41 addq $0x20, %rsp 42 pop %r14 43 pop %rbx 44 pop %rbp 45 ret 46hot_path: 47 addq $0x20, %rsp 48 pop %r14 49 pop %rbx 50 pop %rbp 51 ret 52 .cfi_endproc 53 .size _start, .-_start 54 55# CHECK: BOLT-INFO: Shrink wrapping moved 0 spills inserting load/stores and 0 spills inserting push/pops 56