[Bug tree-optimization/123109] `a >> (bits-1) != 0` is not optimized to `a < 0` by match

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123109

--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Georg-Johann Lay <gjl@gcc.gnu.org>:

https://gcc.gnu.org/g:7a1d4d74e4505c7f44aa8fc90ac9bfc64179309c

commit r17-3827-g7a1d4d74e4505c7f44aa8fc90ac9bfc64179309c
Author: Georg-Johann Lay <avr@gjlay.de>
Date:   Tue Sep 1 19:10:01 2026 +0200

    Fix sloppy PR123109 tests

    gcc.dg/pr123109-vector.c failed with

    FAIL: gcc.dg/pr123109-vector.c (test for excess errors)
    Excess errors:
    gcc.dg/pr123109-vector.c:9:44: warning: right shift count >= width of
vector element [-Wshift-count-overflow]
    gcc.dg/pr123109-vector.c:9:44: warning: right shift count >= width of
vector element [-Wshift-count-overflow]
    gcc.dg/pr123109-vector.c:12:44: warning: right shift count >= width of
vector element [-Wshift-count-overflow]
    gcc.dg/pr123109-vector.c:12:44: warning: right shift count >= width of
vector element [-Wshift-count-overflow]

    gcc.dg/pr123109-vector.c: pattern found 0 times
    FAIL: gcc.dg/pr123109-vector.c scan-tree-dump-times forwprop2 ">= { 0, 0,
0, 0 }" 2

    in the obvious expectation that the vectors have 4 SImode elements.
    Hence use __[U]INT32_TYPE__ for the elements instead of [unsigned] int.

    Similarly, gcc.dg/pr123109-scalar.c failed with:

    FAIL: gcc.dg/pr123109-scalar.c (test for excess errors)
    Excess errors:
    gcc.dg/pr123109-scalar.c:5:44: warning: right shift count >= width of type
[-Wshift-count-overflow]
    gcc.dg/pr123109-scalar.c:5:44: warning: right shift count >= width of type
[-Wshift-count-overflow]
    gcc.dg/pr123109-scalar.c:8:44: warning: right shift count >= width of type
[-Wshift-count-overflow]
    gcc.dg/pr123109-scalar.c:8:44: warning: right shift count >= width of type
[-Wshift-count-overflow]

    gcc.dg/pr123109-scalar.c: pattern found 0 times
    FAIL: gcc.dg/pr123109-scalar.c scan-tree-dump-times optimized ">= 0" 2
    gcc.dg/pr123109-scalar.c: pattern found 0 times
    FAIL: gcc.dg/pr123109-scalar.c scan-tree-dump-times optimized "< 0" 2

    with a similar bogus assumption that int is int32plus.

    gcc/testsuite/
            PR testsuite/123109
            * gcc.dg/pr123109-vector.c (v4si, v4usi): Use SImode elements.
            * gcc.dg/pr123109-scalar.c: Use 32-bit integer types.