[llvm] [X86] Reimplement bundle alignment mode (PR #175830)

[Vitaly Buka via llvm-commits]

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@@ -396,6 +396,36 @@ void MCAssembler::addRelocDirective(RelocDirective RD) {
   relocDirectives.push_back(RD);
 }
 
+/// Write NOPs while limiting the maximum NOP size.
+static void writeControlledNops(raw_ostream &OS, const MCAssembler &Asm,
+                                uint64_t NumBytes, uint64_t FragmentOffset,
+                                uint64_t MaxNopSize,
+                                const MCSubtargetInfo *STI) {
+  uint64_t NumBytesEmitted = 0;
+  while (NumBytesEmitted < NumBytes) {
+    uint64_t NumBytesToEmit = std::min(NumBytes - NumBytesEmitted, MaxNopSize);
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vitalybuka wrote:

Consider `uint64_t NumBytesToEmit = helperFunc()`



https://github.com/llvm/llvm-project/pull/175830