[Bug target/64669] [5 Regression] aarch64-linux profiledbootstrap failure

[jiwang at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64669

--- Comment #5 from Jiong Wang <jiwang at gcc dot gnu.org> ---
Created attachment 34502
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34502&action=edit
kk.ii

attachment is the reduced testcase.

  ./cc1 -g -O2 -fprofile-use  -fno-exceptions -fno-rtti
-fasynchronous-unwind-tables -W -Wall -Wno-narrowing -Wwrite-strings
-Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual -pedantic
-Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -nostdinc++ kk.ii

I found there are two issues,

the first is in kk.ii.183t.optimized

  <bb 15>:
  _10 = _48 == 39;
  _11 = _48 == 10;
  _12 = _10 | _11;
  if (_12 <= 0)
    goto <bb 16>;
  else
    goto <bb 17>;


although there is no correctness issue with the "if (_27 <= 0)", but I think
for boolean type "<= 0" is exactly "== 0", so the "<" is uncessary.

and in this testcase, "_27" happen to be a CCMP candidate, while CCMP code in
aarch64 backend is with the assumption that only EQ/NE comparison will happen
on it. in the bottom of aarch64_get_condition_code_1, if comp_cond is not
NE/EQ, then -1 always returned. So, I think we should treate LE/LEU as EQ?

the second is in do_compare_and_jump in dojump.c, we should use GET_MODE (op0)
to get the mode passed to do_compare_rtx_and_jump instead of use TYPE_MODE
(type) ? 

any thoughts?

after hack above two issues, pass the testcase. (If the tree level never
generate <= for boolean, then only need to modify dojump.c) I am doing more
tests and understand the issue in a systematic way...