[PATCH] D85527: [AIX] Generate unique module id based on PID and timestamp

[Xiangling Liao via Phabricator via llvm-commits]

Xiangling_L marked 3 inline comments as done.
Xiangling_L added inline comments.


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Comment at: llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp:1841
+  std::time_t Now = time(nullptr);
+  if (Now < 0 || !isUInt<64>(Now))
+    return UINT64_MAX;
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jasonliu wrote:
> Not sure what this condition is trying to achieve.
> isUInt takes uint64_t as parameter, and we are asking if a uint64_t type is going to fit in 64 bit width. The answer is always going to be true.
As we discussed offline, current implementation of std::time_t may fail  in 2038. But we will wait until then to see how OS upgrade the implementation and how we can adjust the implementation accordingly if needed.


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Comment at: llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp:1878
+        else
+          // Use PID and current time as unique module id when we cannot
+          // generate one based on a module's strong external symbols.
----------------
jasonliu wrote:
> I think in theory, we only want to take this path when we have a stdin input file. 
> Other than that, we should be able to come up with a sufficiently unique name using output file name and options, etc.
> Could we put a TODO somewhere to indicate that? 
Sure. good suggestion.


Repository:
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  https://reviews.llvm.org/D85527/new/

https://reviews.llvm.org/D85527