[PATCH] D29203: Change debug-info-for-profiling from a TargetOption to a function attribute.

[Dehao Chen via Phabricator via llvm-commits]

danielcdh added inline comments.


================
Comment at: lib/CodeGen/AsmPrinter/DwarfDebug.cpp:1138
+    HasDebugInfoForProfiling=true;
+
   // If there's no debug info for the function we're not going to do anything.
----------------
mehdi_amini wrote:
> danielcdh wrote:
> > mehdi_amini wrote:
> > > ahatanak wrote:
> > > > Is debug-info-for-profiling used to turn on and off debug info for profiling on a per-function basis? I'm not very familiar with this function, but it looks like HasDebugInfoForProfiling is initialized to false in the constructor and then it will always be true after beginFunction is called on a function that has attribute debug-info-for-profiling=true.
> > > Yep that seems broken to me. If foo has the attribute and not bar, we'll emit the profiling debug info for bar if foo is processed first.
> > The issue is that I cannot check for function's attributes in DwarfUnit::applySubprogramAttributes, any suggestions on how I can pass down this attribute to that function?
> Why not do here `HasDebugInfoForProfiling = MF->getFunction()->debugInfoForProfiling();` ?
Because the llvm::DwarfDebug::beginFunction is called first before llvm::DwarfUnit::applySubprogramAttributes are called.

E.g. you have f1, f2, f3

the call sequence is:
beginFunction(f1)
beginFunction(f2)
beginFunction(f3)
applySubprogramAttributes(subprogramof_f1)
applySubprogramAttributes(subprogramof_f2)
applySubprogramAttributes(subprogramof_f3)

The current logic is, if there is any function that has HasDebugInfoForProfiling=true, then all function will have it.


https://reviews.llvm.org/D29203