[BOLT][TEST] Fix stack alignment in section-reloc-with-addend.s

[maksfb]

Summary

Misaligned stack can cause a runtime crash.

bolt/test/runtime/X86/section-reloc-with-addend.s

 # This reproduces a bug triggered by a relocation referencing a section symbol
 # plus a negative reloc. BOLT handles such cases specially, but while doing so,
 # it was failing to sign extend a negative result for the relocation (encoded
 # in the immediate operand of an LEA instruction).
 # Originally triggered by https://fossies.org/linux/glib/glib/guniprop.c
 # Line 550: const gchar *p = special_case_table + val - 0x1000000;
 
 # REQUIRES: system-linux
 
 # RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
 # RUN:   %s -o %t.o
 # Delete our BB symbols so BOLT doesn't mark them as entry points
 # RUN: llvm-strip --strip-unneeded %t.o
 # RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
 
-# RUN: llvm-bolt %t.exe --relocs=1 --print-finalized --print-only=main -o %t.out
+# RUN: llvm-bolt %t.exe --print-finalized --print-only=main -o %t.out \
+# RUN:   2>&1 | FileCheck %s
 
-# RUN: %t.out 1 2
+# RUN: %t.out 1 2 | FileCheck --check-prefix=CHECK-RT %s
 
   .text
   .globl  main
   .type main, %function
   .p2align  4
 main:
   pushq %rbp
   movq  %rsp, %rbp
-  subq  $0x18, %rsp
+  subq  $0x10, %rsp
   cmpl  $0x2, %edi
   jb    .BBend
 .BB2:
-  leaq .data-0x1000000, %rsi     # Use a large negative addend to cause a
+
+# CHECK: leaq
+# CHECK-SAME: {{.*}}-{{.*}}
+  leaq mystring-0x1000000, %rsi  # Use a large negative addend to cause a
                                  # negative result to be encoded in LEA
   addq $0x1000000, %rsi          # Eventually program logic compensates to get
                                  # a real address
   movq $2, %rbx
   xorq %rax, %rax
   movb (%rsi), %al
   addq %rbx, %rax
   movb %al, (%rsi)
   leaq mystring, %rdi
   callq puts
 
 .BBend:
   xorq %rax, %rax
   leaveq
   retq
   .size main, .-main
 
   .data
+
+# CHECK-RT: {{.*}} is rbx mod 10 contents in decimal
 mystring: .asciz "0 is rbx mod 10 contents in decimal\n"