[llvm] [LLVM][ISel][AArch64 Remove AArch64ISD::FCM##z nodes. (PR #135817)

[via llvm-commits]

gulfemsavrun wrote:

We started seeing an assertion failure, and I bisected it to this commit:
```
60507/168895](64) CC obj/third_party/github.com/google/liblc3/src/src/lc3_codec.mdct.c.o
FAILED: [code=1] obj/third_party/github.com/google/liblc3/src/src/lc3_codec.mdct.c.o 
../../prebuilt/third_party/clang/custom/bin/clang -MD -MF obj/third_party/github.com/google/liblc3/src/src/lc3_codec.mdct.c.o.d -D_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS -D_LIBCPP_REMOVE_TRANSITIVE_INCLUDES -D_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS=1 -DZX_ASSERT_LEVEL=2 -I../.. -Igen -I../../third_party/github.com/google/liblc3/src/include -fcolor-diagnostics -fcrash-diagnostics-dir=clang-crashreports -fcrash-diagnostics=all -gen-reproducer=error -ffp-contract=off --sysroot=gen/zircon/public/sysroot --target=aarch64-unknown-fuchsia -ffuchsia-api-level=4293918720 -march=armv8-a+simd+crc+crypto -mtune=generic -ffile-compilation-dir=. -no-canonical-prefixes -fno-omit-frame-pointer -momit-leaf-frame-pointer -fdata-sections -ffunction-sections -O0 -Xclang -debug-info-kind=constructor -g3 -grecord-gcc-switches -gdwarf-5 -gz=zstd -Wall -Wextra -Wconversion -Wextra-semi -Wimplicit-fallthrough -Wnewline-eof -Wstrict-prototypes -Wwrite-strings -Wno-sign-conversion -Wno-unused-parameter -Wnonportable-system-include-path -Wno-missing-field-initializers -Wno-extra-qualification -Wno-cast-function-type-strict -Wno-cast-function-type-mismatch -Wno-unknown-warning-option -Wno-missing-template-arg-list-after-template-kw -Wno-deprecated-pragma -Wno-nontrivial-memaccess -fvisibility=hidden -Werror -Wa,--fatal-warnings -ftrivial-auto-var-init=pattern -Wthread-safety -Wno-unknown-warning-option -Wno-thread-safety-reference-return -Wno-conversion -std=c11 -c ../../third_party/github.com/google/liblc3/src/src/mdct.c -o obj/third_party/github.com/google/liblc3/src/src/lc3_codec.mdct.c.o
clang: llvm/lib/IR/Constants.cpp:1783: const APInt &llvm::Constant::getUniqueInteger() const: Assertion `C && isa<ConstantInt>(C) && "Not a vector of numbers!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: ../../prebuilt/third_party/clang/custom/bin/clang -MD -MF obj/third_party/github.com/google/liblc3/src/src/lc3_codec.mdct.c.o.d -D_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS -D_LIBCPP_REMOVE_TRANSITIVE_INCLUDES -D_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS=1 -DZX_ASSERT_LEVEL=2 -I../.. -Igen -I../../third_party/github.com/google/liblc3/src/include -fcolor-diagnostics -fcrash-diagnostics-dir=clang-crashreports -fcrash-diagnostics=all -gen-reproducer=error -ffp-contract=off --sysroot=gen/zircon/public/sysroot --target=aarch64-unknown-fuchsia -ffuchsia-api-level=4293918720 -march=armv8-a+simd+crc+crypto -mtune=generic -ffile-compilation-dir=. -no-canonical-prefixes -fno-omit-frame-pointer -momit-leaf-frame-pointer -fdata-sections -ffunction-sections -O0 -Xclang -debug-info-kind=constructor -g3 -grecord-gcc-switches -gdwarf-5 -gz=zstd -Wall -Wextra -Wconversion -Wextra-semi -Wimplicit-fallthrough -Wnewline-eof -Wstrict-prototypes -Wwrite-strings -Wno-sign-conversion -Wno-unused-parameter -Wnonportable-system-include-path -Wno-missing-field-initializers -Wno-extra-qualification -Wno-cast-function-type-strict -Wno-cast-function-type-mismatch -Wno-unknown-warning-option -Wno-missing-template-arg-list-after-template-kw -Wno-deprecated-pragma -Wno-nontrivial-memaccess -fvisibility=hidden -Werror -Wa,--fatal-warnings -ftrivial-auto-var-init=pattern -Wthread-safety -Wno-unknown-warning-option -Wno-thread-safety-reference-return -Wno-conversion -std=c11 -c ../../third_party/github.com/google/liblc3/src/src/mdct.c -o obj/third_party/github.com/google/liblc3/src/src/lc3_codec.mdct.c.o
1.	<eof> parser at end of file
2.	Code generation
3.	Running pass 'Function Pass Manager' on module '../../third_party/github.com/google/liblc3/src/src/mdct.c'.
4.	Running pass 'InstructionSelect' on function '@neon_fft_5'
#0 0x0000561163975c78 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (../../prebuilt/third_party/clang/custom/bin/clang+0x91bcc78)
clang: error: clang frontend command failed with exit code 134 (use -v to see invocation)
Fuchsia clang version 21.0.0git (https://llvm.googlesource.com/llvm-project 2a9f77f6bd48d757b2d45aadcb6cf76ef4b4ef32)
Target: aarch64-unknown-fuchsia
Thread model: posix
InstalledDir: ../../prebuilt/third_party/clang/custom/bin
Build config: +assertions
clang: note: diagnostic msg: 
********************
```
https://luci-milo.appspot.com/ui/p/fuchsia/builders/global.ci/clang_toolchain.ci.core.arm64-debug/b8716800273666175553/overview 

https://github.com/llvm/llvm-project/pull/135817