[PATCH] D91234: Add a flag to control whether to propagate labels from condition values to results

[Matt Morehouse via Phabricator via llvm-commits]

morehouse added inline comments.


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Comment at: llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp:191
+static cl::opt<bool>
+    ClTrackControlFlow("dfsan-track-control-flow",
+                       cl::desc("Propagate labels from condition values."),
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It only applies to selects, so maybe we should name it something like `dfsan-track-select-control-flow`. and update the description/comment.


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Comment at: llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp:193
+                       cl::desc("Propagate labels from condition values."),
+                       cl::Hidden, cl::init(false));
+
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This changes the default behavior.  Does it cause any existing tests to fail?

Maybe we should default it to true.


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Comment at: llvm/test/Instrumentation/DataFlowSanitizer/select.ll:50
+
+define <4 x i8> @select8v(i1 %c, <4 x i8> %t, <4 x i8> %f) {
+  ; TRACK_CONTROL_FLOW: %1 = load i16, i16* getelementptr inbounds ([64 x i16], [64 x i16]* @__dfsan_arg_tls, i64 0, i64 2)
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I think this tests the same case as `select8`.  If we want to test the vector one, we need `%c` to be a vector.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D91234/new/

https://reviews.llvm.org/D91234