[PATCH] D50483: [SanitizerCoverage] Add associated metadata to PC guards.

[Matt Morehouse via Phabricator via llvm-commits]

morehouse added inline comments.


================
Comment at: compiler-rt/lib/fuzzer/FuzzerTracePC.cpp:230
+            assert(
+                PCs()[GuardIdx] - ModulePCTable[i].Start[j].PC < 100 &&
+                "PC table entry doesn't match address from PC guard callback");
----------------
eugenis wrote:
> Why 100?
Nothing special about the number except that it's over twice the max distance I've observed between __builtin_return_address(0) from the PC guard callback and the block start address from the PC table.


================
Comment at: llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp:406
   // so we need to prevent them from being dead stripped.
-  if (TargetTriple.isOSBinFormatMachO())
-    appendToUsed(M, GlobalsToAppendToUsed);
----------------
eugenis wrote:
> You are removing MachO-specific code. But !associated is ELF-specific. It has no effect on MachO. What's up with that?
> 
You're right, I will add this back.


https://reviews.llvm.org/D50483