[PATCH] D26718: [llvm] Iterate SmallPtrSet in reverse order to uncover non-determinism in codegen

[Mehdi AMINI via Phabricator via llvm-commits]

mehdi_amini added inline comments.


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Comment at: include/llvm/ADT/SmallPtrSet.h:31
+template <class T = void> struct ReverseIterate { static bool value; };
+template <class T> bool ReverseIterate<T>::value = false;
+}
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Wasn't it the goal of this to have it enabled by default in assert builds?


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Comment at: lib/Support/CommandLine.cpp:55
+template <class T = void> struct ReverseIterate { static bool value; };
+template <class T> bool ReverseIterate<T>::value = false;
+static cl::opt<bool, true> ReverseIteration("reverse-iterate",
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You don't need the redefinition here I think (unless libSupport never imports SmallPtrSet?)



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Comment at: unittests/ADT/CMakeLists.txt:67
+if(DEFINED LLVM_ENABLE_ABI_BREAKING_CHECKS)
+  add_definitions(-DLLVM_ENABLE_ABI_BREAKING_CHECKS)
+  list(APPEND ADTSources ReverseIterationTest.cpp)
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mgrang wrote:
> Without explicitly passing LLVM_ENABLE_ABI_BREAKING_CHECKS to the compilation line of ReverseIteration.cpp, it always complains about undefined variable "ReverseIterate".
That's not great, but I don't see a better way right now, can you at least document it in file here?


https://reviews.llvm.org/D26718