[Bug rtl-optimization/77714] New: Wrong code generation for gcc.c-torture/execute/pr51447.c

[thopre01 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77714

            Bug ID: 77714
           Summary: Wrong code generation for
                    gcc.c-torture/execute/pr51447.c
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: thopre01 at gcc dot gnu.org
                CC: bergner at vnet dot ibm.com
  Target Milestone: ---
              Host: x86_64-linux-gnu
            Target: arm-none-eabi

Hi,

GCC started to generate wrong coed for gcc.c-torture/execute/pr51447.c from
r240065 on arm-none-eabi Cortex-M0 targets (no problem on other Cortex-M
targets). The problem is that the stack is no longer properly adjusted after
jumping from bar to nonlocal_lab.

Dumps are identical until reload. Before this commit, reload will do the
adjustment of the stack in r7 and then pro_and_epilogue will add a mov sp, r7.
After the commit, the stack is adjusted in ip but pro_and_epilogue still
generates a mov sp, r7.

Please find attached the assembly output before and after as well as the dumps
for ira, reload and pro_and_epilogue.

Best regards.