[PATCH] D130947: TableGen: Introduce generated getSubRegisterClass function

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/SIFixSGPRCopies.cpp:280
 
-    SrcRC = TRI->getSubRegClass(SrcRC, SrcSubReg);
+    if (SrcSubReg)
+      SrcRC = TRI->getSubRegisterClass(SrcRC, SrcSubReg);
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Why add this "if", given that the generated method handles the NoSubregister case?


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Comment at: llvm/utils/TableGen/RegisterInfoEmitter.cpp:1554
+    // sentinel.
+    if (RegisterClasses.size() < UINT8_MAX)
+      OS << "  static const uint8_t Table[";
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I know this is copied from above but it should be `<=` not `<`.


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Comment at: llvm/utils/TableGen/RegisterInfoEmitter.cpp:1589
+    OS << "  };\n  assert(RC && \"Missing regclass\");\n"
+       << "  if (!Idx) return RC;\n  --Idx;\n"
+       << "  assert(Idx < " << SubRegIndicesSize << " && \"Bad subreg\");\n"
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This looks like you are handling the NoSubregister case.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130947/new/

https://reviews.llvm.org/D130947