[llvm] [InstCombine] Slightly optimize visitFcmp (NFC) (PR #156097)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `lldb-x86_64-debian` running on `lldb-x86_64-debian` while building `llvm` at step 6 "test".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/162/builds/30110

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

```
Step 6 (test) failure: build (failure)
...
PASS: lldb-shell :: Commands/command-disassemble.s (1430 of 3181)
PASS: lldb-shell :: REPL/Basic.test (1431 of 3181)
PASS: lldb-shell :: SymbolFile/DWARF/x86/debug-types-debug-names.cpp (1432 of 3181)
PASS: lldb-shell :: Commands/command-list-reach-end-of-file.test (1433 of 3181)
PASS: lldb-shell :: SymbolFile/DWARF/x86/member-pointers.cpp (1434 of 3181)
PASS: lldb-unit :: Core/./LLDBCoreTests/91/118 (1435 of 3181)
PASS: lldb-shell :: SymbolFile/DWARF/dwo-debug-file-search-paths-filename-only-relative-compdir.c (1436 of 3181)
PASS: lldb-shell :: SymbolFile/DWARF/x86/simplified-template-names.cpp (1437 of 3181)
PASS: lldb-api :: tools/lldb-server/TestLldbGdbServer.py (1438 of 3181)
PASS: lldb-unit :: Core/./LLDBCoreTests/69/118 (1439 of 3181)
FAIL: lldb-unit :: DAP/./DAPTests/10/74 (1440 of 3181)
******************** TEST 'lldb-unit :: DAP/./DAPTests/10/74' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/unittests/DAP/./DAPTests-lldb-unit-1429192-10-74.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=74 GTEST_SHARD_INDEX=10 /home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/unittests/DAP/./DAPTests
--

Script:
--
/home/worker/2.0.1/lldb-x86_64-debian/build/tools/lldb/unittests/DAP/./DAPTests --gtest_filter=DisconnectRequestHandlerTest.DisconnectTriggersTerminateCommands
--
/home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/unittests/DAP/Handler/DisconnectTest.cpp:51: Failure
Actual function call count doesn't match EXPECT_CALL(client, Received(Output("1\n")))...
         Expected: to be called once
           Actual: never called - unsatisfied and active

/home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/unittests/DAP/Handler/DisconnectTest.cpp:52: Failure
Actual function call count doesn't match EXPECT_CALL(client, Received(Output("2\n")))...
         Expected: to be called twice
           Actual: called once - unsatisfied and active


/home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/unittests/DAP/Handler/DisconnectTest.cpp:51
Actual function call count doesn't match EXPECT_CALL(client, Received(Output("1\n")))...
         Expected: to be called once
           Actual: never called - unsatisfied and active

/home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/unittests/DAP/Handler/DisconnectTest.cpp:52
Actual function call count doesn't match EXPECT_CALL(client, Received(Output("2\n")))...
         Expected: to be called twice
           Actual: called once - unsatisfied and active



********************
PASS: lldb-shell :: SymbolFile/DWARF/x86/find-basic-namespace.cpp (1441 of 3181)
PASS: lldb-shell :: SymbolFile/DWARF/DW_AT_range-DW_FORM_sec_offset.s (1442 of 3181)
PASS: lldb-shell :: Expr/TestStringLiteralExpr.test (1443 of 3181)
PASS: lldb-shell :: SymbolFile/DWARF/packed.cpp (1444 of 3181)

```

</details>

https://github.com/llvm/llvm-project/pull/156097