[PATCH] D97268: [X86] Use correct padding when in 16-bit mode

[Bill Wendling via Phabricator via llvm-commits]

void created this revision.
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void requested review of this revision.
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In 16-bit mode, some of the nop patterns used in 32-bit mode can end up
mangling other instructions. For instance, an aligned "movz" instruction
may have the 0x66 and 0x67 prefixes omitted, because the nop that's used
messes things up.

  xorl    %ebx, %ebx
  .p2align 4, 0x90
  movzbl  (%esi,%ebx), %ecx

Use instead nop patterns we know 16-bit mode can handle.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D97268

Files:
  lld/test/COFF/lto-cpu-string.ll
  lld/test/COFF/lto.ll
  lld/test/ELF/lto/cpu-string.ll
  lld/test/ELF/lto/mllvm.ll
  lld/test/MachO/cpu-string.ll
  llvm/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
  llvm/test/MC/COFF/align-nops.s
  llvm/test/MC/ELF/align-nops.s
  llvm/test/MC/MachO/x86_32-optimal_nop.s
  llvm/test/MC/X86/AlignedBundling/long-nop-pad.s
  llvm/test/MC/X86/AlignedBundling/misaligned-bundle-group.s
  llvm/test/MC/X86/AlignedBundling/misaligned-bundle.s
  llvm/test/MC/X86/AlignedBundling/pad-align-to-bundle-end.s
  llvm/test/MC/X86/AlignedBundling/pad-bundle-groups.s
  llvm/test/MC/X86/AlignedBundling/relax-at-bundle-end.s
  llvm/test/MC/X86/AlignedBundling/relax-in-bundle-group.s
  llvm/test/MC/X86/AlignedBundling/single-inst-bundling.s
  llvm/test/MC/X86/align-branch-pad-max-prefix.s
  llvm/test/MC/X86/align-via-padding.s
  llvm/test/MC/X86/align-via-relaxation.s
  llvm/test/MC/X86/code16gcc-align.s
  llvm/test/MC/X86/x86_64-directive-nops.s
  llvm/test/MC/X86/x86_long_nop.s
  llvm/test/MC/X86/x86_nop.s
  llvm/test/tools/llvm-profgen/symbolize.ll

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