[llvm] 51e1c02 - [X86] Add back comment inadvertently lost in 1a1448e6568d9b11f198e510fa9c4cb6b1f4216a.

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2020-07-27T10:02:38-07:00
New Revision: 51e1c028d4021eba64a56e684d34bb164c244d43

URL: https://github.com/llvm/llvm-project/commit/51e1c028d4021eba64a56e684d34bb164c244d43
DIFF: https://github.com/llvm/llvm-project/commit/51e1c028d4021eba64a56e684d34bb164c244d43.diff

LOG: [X86] Add back comment inadvertently lost in 1a1448e6568d9b11f198e510fa9c4cb6b1f4216a.

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86MCInstLower.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/X86/X86MCInstLower.cpp b/llvm/lib/Target/X86/X86MCInstLower.cpp
index 8f3e32727371..af86c1fc7206 100644
--- a/llvm/lib/Target/X86/X86MCInstLower.cpp
+++ b/llvm/lib/Target/X86/X86MCInstLower.cpp
@@ -1083,6 +1083,9 @@ void X86AsmPrinter::LowerTlsAddr(X86MCInstLower &MCInstLowering,
 /// bytes.  Return the size of nop emitted.
 static unsigned emitNop(MCStreamer &OS, unsigned NumBytes,
                         const X86Subtarget *Subtarget) {
+  // Determine the longest nop which can be efficiently decoded for the given
+  // target cpu.  15-bytes is the longest single NOP instruction, but some
+  // platforms can't decode the longest forms efficiently.
   unsigned MaxNopLength = 1;
   if (Subtarget->is64Bit()) {
     // FIXME: We can use NOOPL on 32-bit targets with FeatureNOPL, but the