56 lines · plain
1## This checks that shrink wrapping does attempt at accessing stack elements2## using RSP when the function is aligning RSP and changing offsets.3 4# REQUIRES: system-linux5 6# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \7# RUN: %s -o %t.o8# RUN: link_fdata %s %t.o %t.fdata9# RUN: llvm-strip --strip-unneeded %t.o10# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q -nostdlib11# 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 %s14 15## Here we have a function that aligns the stack at prologue. Stack pointer16## analysis can't try to infer offset positions after AND because that depends17## on the runtime value of the stack pointer of callee (whether it is misaligned18## or not).19 .globl _start20 .type _start, %function21_start:22 .cfi_startproc23# FDATA: 0 [unknown] 0 1 _start 0 0 124 push %rbp25 mov %rsp, %rbp26 push %rbx27 push %r1428 and $0xffffffffffffffe0,%rsp29 subq $0x20, %rsp30b: je hot_path31# FDATA: 1 _start #b# 1 _start #hot_path# 0 132cold_path:33 mov %r14, %rdi34 mov %rbx, %rdi35 # Block push-pop mode by using an instruction that requires the36 # stack to be aligned to 128B. This will force the pass37 # to try to index stack elements by using RSP +offset directly, but38 # we do not know how to access individual elements of the stack thanks39 # to the alignment.40 movdqa %xmm8, (%rsp)41 addq $0x20, %rsp42 pop %r1443 pop %rbx44 pop %rbp45 ret46hot_path:47 addq $0x20, %rsp48 pop %r1449 pop %rbx50 pop %rbp51 ret52 .cfi_endproc53 .size _start, .-_start54 55# CHECK: BOLT-INFO: Shrink wrapping moved 0 spills inserting load/stores and 0 spills inserting push/pops56