[llvm] [IR] Add initial support for the byte type (PR #178666)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-riscv-rva20-2stage` running on `rise-clang-riscv-rva20-2stage` while building `llvm` at step 4 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/87/builds/5812

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

```
Step 4 (annotate) failure: '../llvm-zorg/zorg/buildbot/builders/annotated/rise-riscv-build.sh --jobs=32' (failure)
...
PASS: LLVM :: CodeGen/X86/bswap.ll (53502 of 92206)
PASS: LLVM :: CodeGen/X86/bmi-select-distrib.ll (53503 of 92206)
PASS: LLVM :: CodeGen/X86/bitcast-int-to-vector-bool-zext.ll (53504 of 92206)
PASS: LLVM :: CodeGen/X86/avx512bwvl-intrinsics-upgrade.ll (53505 of 92206)
PASS: LLVM :: CodeGen/X86/buildvec-bitcast.ll (53506 of 92206)
PASS: LLVM :: CodeGen/X86/bug47278.mir (53507 of 92206)
PASS: LLVM :: CodeGen/X86/bitcast-vector-bool.ll (53508 of 92206)
PASS: LLVM :: CodeGen/X86/bug47278-eflags-error.mir (53509 of 92206)
PASS: LLVM :: CodeGen/X86/byref.ll (53510 of 92206)
PASS: LLVM :: CodeGen/X86/bit-manip-i256.ll (53511 of 92206)
FAIL: LLVM :: CodeGen/X86/byte-constants.ll (53512 of 92206)
******************** TEST 'LLVM :: CodeGen/X86/byte-constants.ll' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
/home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/llc < /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll | /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/FileCheck /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll
# executed command: /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/llc
# executed command: /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/FileCheck /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll
# .---command stderr------------
# | /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll:23:10: error: CHECK: expected string not found in input
# | ; CHECK: .long 42
# |          ^
# | <stdin>:27:3: note: scanning from here
# | r:
# |   ^
# | <stdin>:28:2: note: possible intended match here
# |  .word 42 # 0x2a
# |  ^
# | 
# | Input file: <stdin>
# | Check file: /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |             .
# |             .
# |             .
# |            22:  .size f, 1 
# |            23:  
# |            24:  .type r, at object # @r 
# |            25:  .globl r 
# |            26:  .p2align 2, 0x0 
# |            27: r: 
# | check:23'0       X error: no match found
# |            28:  .word 42 # 0x2a 
Step 11 (llvm-project check-all) failure: llvm-project check-all (failure)
...
PASS: LLVM :: CodeGen/X86/bswap.ll (53502 of 92206)
PASS: LLVM :: CodeGen/X86/bmi-select-distrib.ll (53503 of 92206)
PASS: LLVM :: CodeGen/X86/bitcast-int-to-vector-bool-zext.ll (53504 of 92206)
PASS: LLVM :: CodeGen/X86/avx512bwvl-intrinsics-upgrade.ll (53505 of 92206)
PASS: LLVM :: CodeGen/X86/buildvec-bitcast.ll (53506 of 92206)
PASS: LLVM :: CodeGen/X86/bug47278.mir (53507 of 92206)
PASS: LLVM :: CodeGen/X86/bitcast-vector-bool.ll (53508 of 92206)
PASS: LLVM :: CodeGen/X86/bug47278-eflags-error.mir (53509 of 92206)
PASS: LLVM :: CodeGen/X86/byref.ll (53510 of 92206)
PASS: LLVM :: CodeGen/X86/bit-manip-i256.ll (53511 of 92206)
FAIL: LLVM :: CodeGen/X86/byte-constants.ll (53512 of 92206)
******************** TEST 'LLVM :: CodeGen/X86/byte-constants.ll' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 1
/home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/llc < /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll | /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/FileCheck /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll
# executed command: /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/llc
# executed command: /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/stage2/bin/FileCheck /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll
# .---command stderr------------
# | /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll:23:10: error: CHECK: expected string not found in input
# | ; CHECK: .long 42
# |          ^
# | <stdin>:27:3: note: scanning from here
# | r:
# |   ^
# | <stdin>:28:2: note: possible intended match here
# |  .word 42 # 0x2a
# |  ^
# | 
# | Input file: <stdin>
# | Check file: /home/buildbot-worker/bbroot/clang-riscv-rva20-2stage/llvm/llvm/test/CodeGen/X86/byte-constants.ll
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |             .
# |             .
# |             .
# |            22:  .size f, 1 
# |            23:  
# |            24:  .type r, at object # @r 
# |            25:  .globl r 
# |            26:  .p2align 2, 0x0 
# |            27: r: 
# | check:23'0       X error: no match found
# |            28:  .word 42 # 0x2a 

```

</details>

https://github.com/llvm/llvm-project/pull/178666