[llvm] [LV] Move 3 functions into VPlanTransforms (NFC) (PR #158644)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-sve2-vla-2stage` running on `linaro-g4-02` while building `llvm` at step 12 "ninja check 2".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/199/builds/6331

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

```
Step 12 (ninja check 2) failure: stage 2 checked (failure)
******************** TEST 'LLVM :: tools/llvm-exegesis/AArch64/no-aliasing-ld-str.s' FAILED ********************
Exit Code: -7

Command Output (stdout):
--
# RUN: at line 3
/home/tcwg-buildbot/worker/clang-aarch64-sve2-vla-2stage/stage2/bin/llvm-exegesis -mtriple=aarch64 -mcpu=neoverse-v2 -mode=latency --dump-object-to-disk=%d --opcode-name=FMOVWSr --benchmark-phase=assemble-measured-code 2>&1
# executed command: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla-2stage/stage2/bin/llvm-exegesis -mtriple=aarch64 -mcpu=neoverse-v2 -mode=latency --dump-object-to-disk=%d --opcode-name=FMOVWSr --benchmark-phase=assemble-measured-code
# .---command stdout------------
# | Check generated assembly with: /usr/bin/objdump -d %d
# | ---
# | mode:            latency
# | key:
# |   instructions:
# |     - 'FMOVWSr S17 W18'
# |     - 'FCVTNSUWSr W23 S17'
# |   config:          ''
# |   register_initial_values:
# |     - 'W18=0x0'
# |     - 'FPCR=0x0'
# | cpu_name:        neoverse-v2
# | llvm_triple:     aarch64
# | min_instructions: 10000
# | measurements:    []
# | error:           actual measurements skipped.
# | info:            Repeating two instructions
# | assembled_snippet: F70F1FF812008052080080D208441BD55102271E3702201E5102271E3702201E5102271E3702201E5102271E3702201EF70741F8C0035FD6
# | ...
# `-----------------------------
# RUN: at line 4
/home/tcwg-buildbot/worker/clang-aarch64-sve2-vla-2stage/stage2/bin/llvm-objdump -d %d > /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla-2stage/stage2/test/tools/llvm-exegesis/AArch64/Output/no-aliasing-ld-str.s.tmp.s
# executed command: /home/tcwg-buildbot/worker/clang-aarch64-sve2-vla-2stage/stage2/bin/llvm-objdump -d %d
# .---redirected output from '/home/tcwg-buildbot/worker/clang-aarch64-sve2-vla-2stage/stage2/test/tools/llvm-exegesis/AArch64/Output/no-aliasing-ld-str.s.tmp.s'
# | 
# | %d:	file format elf64-littleaarch64
# | 
# | Disassembly of section .text:
# | 
# | 0000000000000000 <foo>:
# |        0: f81f0ff7     	str	x23, [sp, #-0x10]!
# |        4: 52800012     	mov	w18, #0x0               // =0
# |        8: d2800008     	mov	x8, #0x0                // =0
# |        c: d51b4408     	msr	FPCR, x8
# |       10: 1e270251     	fmov	s17, w18
# |       14: 1e200237     	fcvtns	w23, s17
# |       18: 1e270251     	fmov	s17, w18
# |       1c: 1e200237     	fcvtns	w23, s17
# |       20: 1e270251     	fmov	s17, w18
# |       24: 1e200237     	fcvtns	w23, s17
# |       28: 1e270251     	fmov	s17, w18
...

```

</details>

https://github.com/llvm/llvm-project/pull/158644