[PATCH] D146463: [CodeGen][RISCV] Change Shadow Call Stack Register to X3

Mon Apr 10 14:47:06 PDT 2023

paulkirth added inline comments.

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Comment at: clang/lib/Driver/SanitizerArgs.cpp:307

+bool shadowCallStackDSLConflicts(const llvm::opt::ArgList &Args,
+                                 const llvm::Triple &TT) {
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mcgrathr wrote:
> I'm guessing that "DSL" stands for "data small limit" or something, which is confusing since the thing is called small-data-limit, not data-small-limit. Anyway, this is the first use I've seen of DSL as an abbreviation related to any of this. I think it would be clear enough to just call it `shadowCallStackConflicts` since it's responsible for detecting conflicts between shadow-call-stack and whatever is relevant to that in the particular target.
> 
Oops. Seems to be a typo. Thank you.

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Comment at: clang/lib/Driver/SanitizerArgs.cpp:573
+                                 Kinds & SanitizerKind::ShadowCallStack)
+          << "-msmall-data-limit=0";
+    }
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jrtc27 wrote:
> Why is this an error? It may be a misguided thing to enable but it is 100% supported to combine this. All the limit does is put things in .sdata, but they can still be addressed just fine.
My understanding is that (whether they should or not) linkers are using the presence of the `.sdata` section to enable gp relaxation. 

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D146463/new/

https://reviews.llvm.org/D146463