Fix copysign activity analysis (rust-lang#440)

EnzymeAD · Jan 27, 2022 · 36d2661 · 36d2661
1 parent bb7e879
commit 36d2661
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/enzyme/Enzyme/ActivityAnalysis.cpp b/enzyme/Enzyme/ActivityAnalysis.cpp
@@ -319,6 +319,12 @@ static inline void propagateArgumentInformation(
         Name == "__cxa_guard_abort")
       return;
 
+    /// Only the first argument (magnitude) of copysign is active
+    if (F->getIntrinsicID() == Intrinsic::copysign) {
+      propagateFromOperand(CI.getOperand(0));
+      return;
+    }
+
     /// Only the src/dst in memset/memcpy/memmove impact the activity of the
     /// instruction
     // memset cannot propagate activity as it sets