[PATCH] D66724: [AIX]Emit function descriptor csect in assembly

Sat Sep 7 08:37:04 PDT 2019

sfertile added inline comments.

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Comment at: llvm/lib/MC/MCExpr.cpp:445
 void MCSymbolRefExpr::printVariantKind(raw_ostream &OS) const {
-  if (UseParensForSymbolVariant)
+  if (getKind() == MCSymbolRefExpr::VK_PPC_TOC_TC0)
+    OS << '[' << MCSymbolRefExpr::getVariantKindName(getKind()) << ']';
----------------
jasonliu wrote:
> I don't quite like how we do the special case here just for VK_PPC_TOC_TC0 kind.
> Not sure if we can do something better. Or we could leave it like this for now, and if we find other MCSymbolRefExpr like this, we could common them up. 
> Any thoughts, @sfertile @hubert.reinterpretcast  ?
I'm not aware of any other square brackets used in symbol references on AIX, but I'm still pretty new to AIX assembly so that doesn't mean there isn't any.

We *could* add a bitfield to the MCSymbolRefExpr (similar to the `UseParensForSymbolVariant` field, but then we likely just have the same 'if' in the SymbolRef constructor to set the new bitfield. 

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D66724/new/

https://reviews.llvm.org/D66724