[PATCH] D131631: [MSAN] Separate id ptr from constant string for variable names used in track origins.

[Kevin Athey via Phabricator via llvm-commits]

kda added inline comments.


================
Comment at: llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp:3904
+      Value *Descr = getLocalVarDescription(I);
       IRB.CreateCall(MS.MsanSetAllocaOriginFn,
                      {IRB.CreatePointerCast(&I, IRB.getInt8PtrTy()), Len,
----------------
vitalybuka wrote:
> kda wrote:
> > vitalybuka wrote:
> > > ```
> > > if (ClPrintLocalVNames) {
> > >   IRB.CreateCall(MS.MsanSetAllocaOriginNameFn, ...
> > > } else {
> > >   IRB.CreateCall(MS.MsanSetAllocaOriginFn, ...
> > > }
> > > ```
> > What is the goal here?
> > Is this to allow the variable names to be dropped from the binary to save even more size?
> yes
I'm going to do this in a follow up CL, because I think it requires adding another function that has the Idptr parameter, but not the Descr, as well as having to modify msan_report to handle nullptr for description.


Repository:
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  https://reviews.llvm.org/D131631/new/

https://reviews.llvm.org/D131631