[PATCH] D19293: [profile] LLVM support for memory-mapping profile counters

[David Li via llvm-commits]

davidxl added inline comments.

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Comment at: lib/ProfileData/InstrProfReader.cpp:288
@@ +287,3 @@
+  // occurs when memory-mapping tightly packed sections into the profile.
+  for (; CurrentPos + sizeof(RawInstrProf::Header) <= End;
+       CurrentPos += sizeof(uint64_t)) {
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Using the for-loop and pattern matching Magic seems weird. Can the paddings be zero filled?

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Comment at: lib/Transforms/Instrumentation/InstrProfiling.cpp:390
@@ -385,1 +389,3 @@
 
+void InstrProfiling::emitCounterPadding() {
+  auto PageSize = llvm::sys::Process::getPageSize();
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Should this be conditionally emitted for darwin only?

Also do you need to emit this padding bytes per module?  Have you considered using linker script to do that?


http://reviews.llvm.org/D19293