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Commit migrated from https://github.com/dotnet/coreclr/commit/1fd05c6120036bf180b595aa2321d8656a02c3d7

diff --git a/src/coreclr/src/jit/gentree.cpp b/src/coreclr/src/jit/gentree.cpp
index 39245ba..dd244b7 100644 (file)
--- a/src/coreclr/src/jit/gentree.cpp
+++ b/src/coreclr/src/jit/gentree.cpp
@@ -12049,6 +12049,9 @@ GenTreePtr Compiler::gtFoldExprConst(GenTreePtr tree)
 
                         if (d1 <= -1.0 && varTypeIsUnsigned(tree->CastToType())) 
                         {
+                            // Don't fold conversions of these cases becasue the result is unspecified per ECMA spec
+                            // and the native math doing the fold doesn't match the run-time computation on all platforms.
+                            // We want the behavior to be same with or without folding.
                             return tree;
                         }