vendor/llvm/llvm-release_40-r293807

1 files changed, 4 insertions, 1 deletions

diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp
index 34be90692481b..ede381c4c2430 100644
--- a/lib/Transforms/Scalar/SCCP.cpp
+++ b/lib/Transforms/Scalar/SCCP.cpp
@@ -1705,7 +1705,10 @@ static bool runIPSCCP(Module &M, const DataLayout &DL,
 
     // If this is an exact definition of this function, then we can propagate
     // information about its result into callsites of it.
-    if (F.hasExactDefinition())
+    // Don't touch naked functions. They may contain asm returning a
+    // value we don't see, so we may end up interprocedurally propagating
+    // the return value incorrectly.
+    if (F.hasExactDefinition() && !F.hasFnAttribute(Attribute::Naked))
       Solver.AddTrackedFunction(&F);
 
     // If this function only has direct calls that we can see, we can track its