diff --git a/lib/Target/X86/X86InstrCompiler.td b/lib/Target/X86/X86InstrCompiler.td
index 117b6ff2103..bf25672b2f6 100644
--- a/lib/Target/X86/X86InstrCompiler.td
+++ b/lib/Target/X86/X86InstrCompiler.td
@@ -1191,7 +1191,6 @@ def def32 : PatLeaf<(i32 GR32:$src), [{
   return N->getOpcode() != ISD::TRUNCATE &&
          N->getOpcode() != TargetOpcode::EXTRACT_SUBREG &&
          N->getOpcode() != ISD::CopyFromReg &&
-         N->getOpcode() != ISD::AssertSext &&
          N->getOpcode() != X86ISD::CMOV;
 }]>;
 
diff --git a/test/CodeGen/X86/TruncAssertZext.ll b/test/CodeGen/X86/TruncAssertZext.ll
deleted file mode 100644
index 08079e98f2d..00000000000
--- a/test/CodeGen/X86/TruncAssertZext.ll
+++ /dev/null
@@ -1,16 +0,0 @@
-; RUN: llc < %s -O2 -march=x86-64 | FileCheck %s
-; Checks that a zeroing mov is inserted for the trunc/zext pair even when
-; the source of the zext is an AssertSext node
-; PR20494
-
-define i64 @main(i64 %a) { 
-; CHECK-LABEL: main
-; CHECK: movl %ecx, %eax
-; CHECK: ret
-  %or = or i64 %a, -2
-  %trunc = trunc i64 %or to i32
-  br label %l
-l:
-  %ext = zext i32 %trunc to i64
-  ret i64 %ext
-}