[llvm] [DAG] Fold rem(rem(A, BCst), Op1Cst) -> rem(A, Op1Cst) (PR #159517)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-m68k-linux-cross` running on `suse-gary-m68k-cross` while building `llvm` at step 5 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/27/builds/16404

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 5 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'lit :: shtest-readfile.py' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 3
env LIT_USE_INTERNAL_SHELL=1  not env -u FILECHECK_OPTS "/usr/bin/python3.11" /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/llvm/llvm/utils/lit/lit.py -j1 --order=lexical -a -v Inputs/shtest-readfile | FileCheck -match-full-lines -DTEMP_PATH=/var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/Inputs/shtest-readfile/Output /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/shtest-readfile.py
# executed command: env LIT_USE_INTERNAL_SHELL=1 not env -u FILECHECK_OPTS /usr/bin/python3.11 /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/llvm/llvm/utils/lit/lit.py -j1 --order=lexical -a -v Inputs/shtest-readfile
# executed command: FileCheck -match-full-lines -DTEMP_PATH=/var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/Inputs/shtest-readfile/Output /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/shtest-readfile.py
# .---command stderr------------
# | /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/shtest-readfile.py:8:10: error: CHECK: expected string not found in input
# | # CHECK: echo hello
# |          ^
# | <stdin>:2:53: note: scanning from here
# | FAIL: shtest-readfile :: absolute-paths.txt (1 of 4)
# |                                                     ^
# | <stdin>:10:19: note: possible intended match here
# | # executed command: echo -n hello
# |                   ^
# | 
# | Input file: <stdin>
# | Check file: /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/shtest-readfile.py
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |            1: -- Testing: 4 tests, 1 workers -- 
# |            2: FAIL: shtest-readfile :: absolute-paths.txt (1 of 4) 
# | check:8'0                                                         X error: no match found
# |            3: ******************** TEST 'shtest-readfile :: absolute-paths.txt' FAILED ******************** 
# | check:8'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            4: Exit Code: 1 
# | check:8'0     ~~~~~~~~~~~~~
# |            5:  
# | check:8'0     ~
# |            6: Command Output (stdout): 
# | check:8'0     ~~~~~~~~~~~~~~~~~~~~~~~~~
# |            7: -- 
# | check:8'0     ~~~
# |            8: # RUN: at line 2 
# | check:8'0     ~~~~~~~~~~~~~~~~~
# |            9: echo -n "hello" > /var/lib/buildbot/workers/suse-gary-m68k-cross/clang-m68k-linux-cross/stage1/utils/lit/tests/Inputs/shtest-readfile/Output/absolute-paths.txt.tmp 
# | check:8'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |           10: # executed command: echo -n hello 
# | check:8'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | check:8'1                       ?                possible intended match
# |           11: # RUN: at line 3 
# | check:8'0     ~~~~~~~~~~~~~~~~~
# |           12: echo  
...

```

</details>

https://github.com/llvm/llvm-project/pull/159517