[clang] [CodeGen] Fix volatile inst (PR #171862)

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github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Windows-->
# :window: Windows x64 Test Results

* 51492 tests passed
* 864 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### Clang
<details>
<summary>Clang.CodeGen/ms-intrinsics.c</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
c:\_work\llvm-project\llvm-project\build\bin\clang.exe -cc1 -internal-isystem C:\_work\llvm-project\llvm-project\build\lib\clang\22\include -nostdsysteminc -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=17.00          -triple i686--windows -Oz -emit-llvm C:\_work\llvm-project\llvm-project\clang\test\CodeGen\ms-intrinsics.c -o -          | c:\_work\llvm-project\llvm-project\build\bin\filecheck.exe C:\_work\llvm-project\llvm-project\clang\test\CodeGen\ms-intrinsics.c -check-prefixes CHECK,CHECK-I386,CHECK-INTEL
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\clang.exe' -cc1 -internal-isystem 'C:\_work\llvm-project\llvm-project\build\lib\clang\22\include' -nostdsysteminc -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=17.00 -triple i686--windows -Oz -emit-llvm 'C:\_work\llvm-project\llvm-project\clang\test\CodeGen\ms-intrinsics.c' -o -
# note: command had no output on stdout or stderr
# executed command: 'c:\_work\llvm-project\llvm-project\build\bin\filecheck.exe' 'C:\_work\llvm-project\llvm-project\clang\test\CodeGen\ms-intrinsics.c' -check-prefixes CHECK,CHECK-I386,CHECK-INTEL
# .---command stderr------------
# | C:\_work\llvm-project\llvm-project\clang\test\CodeGen\ms-intrinsics.c:595:11: error: CHECK: expected string not found in input
# | // CHECK: = load volatile i8, ptr %p
# |           ^
# | <stdin>:353:69: note: scanning from here
# | define dso_local signext i8 @test_iso_volatile_load8(ptr noundef %p) local_unnamed_addr #11 {
# |                                                                     ^
# | <stdin>:355:12: note: possible intended match here
# |  %0 = load atomic volatile i8, ptr %p monotonic, align 1
# |            ^
# | 
# | Input file: <stdin>
# | Check file: C:\_work\llvm-project\llvm-project\clang\test\CodeGen\ms-intrinsics.c
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |              .
# |              .
# |              .
# |            348:  %1 = add i32 %0, -1 
# |            349:  ret i32 %1 
# |            350: } 
# |            351:  
# |            352: ; Function Attrs: minsize mustprogress nofree norecurse nounwind optsize willreturn memory(argmem: readwrite, inaccessiblemem: readwrite) 
# |            353: define dso_local signext i8 @test_iso_volatile_load8(ptr noundef %p) local_unnamed_addr #11 { 
# | check:595'0                                                                         X~~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
# |            354: entry: 
# | check:595'0     ~~~~~~~
# |            355:  %0 = load atomic volatile i8, ptr %p monotonic, align 1 
# | check:595'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | check:595'1                ?                                              possible intended match
# |            356:  ret i8 %0 
# | check:595'0     ~~~~~~~~~~~
# |            357: } 
# | check:595'0     ~~
# |            358:  
# | check:595'0     ~
# |            359: ; Function Attrs: minsize mustprogress nofree norecurse nounwind optsize willreturn memory(argmem: readwrite, inaccessiblemem: readwrite) 
# | check:595'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            360: define dso_local signext i16 @test_iso_volatile_load16(ptr noundef %p) local_unnamed_addr #11 { 
# | check:595'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |              .
# |              .
# |              .
# | >>>>>>
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/171862