Index: lib/Target/X86/ShadowCallStack.cpp
===================================================================
--- lib/Target/X86/ShadowCallStack.cpp
+++ lib/Target/X86/ShadowCallStack.cpp
@@ -242,7 +242,8 @@
       for (auto &LiveIn : MBB.liveins())
         UsedRegs.set(LiveIn.PhysReg);
       for (auto &MI : MBB) {
-        InstructionCount++;
+        if (!MI.isDebugValue() && !MI.isCFIInstruction() && !MI.isLabel())
+          InstructionCount++;
         for (auto &Op : MI.operands())
           if (Op.isReg() && Op.isDef())
             UsedRegs.set(Op.getReg());
Index: test/CodeGen/X86/shadow-call-stack.mir
===================================================================
--- test/CodeGen/X86/shadow-call-stack.mir
+++ test/CodeGen/X86/shadow-call-stack.mir
@@ -106,6 +106,14 @@
 body: |
   ; CHECK: bb.0:
   bb.0:
+    ; Ensure these are not counted as machine instructions
+    CFI_INSTRUCTION 0
+    CFI_INSTRUCTION 0
+    CFI_INSTRUCTION 0
+    DBG_VALUE 0
+    DBG_VALUE 0
+    DBG_VALUE 0
+
     ; CHECK: $eax = MOV32ri 13
     $eax = MOV32ri 13