Index: llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
===================================================================
--- llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -4007,12 +4007,12 @@
     // Is this guard followed by another guard?  We scan forward over a small
     // fixed window of instructions to handle common cases with conditions
     // computed between guards.
-    Instruction *NextInst = II->getNextNode();
+    Instruction *NextInst = II->getNextNonDebugInstruction();
     for (unsigned i = 0; i < GuardWideningWindow; i++) {
       // Note: Using context-free form to avoid compile time blow up
       if (!isSafeToSpeculativelyExecute(NextInst))
         break;
-      NextInst = NextInst->getNextNode();
+      NextInst = NextInst->getNextNonDebugInstruction();
     }
     Value *NextCond = nullptr;
     if (match(NextInst,
@@ -4024,10 +4024,10 @@
         return eraseInstFromFunction(*NextInst);
 
       // Otherwise canonicalize guard(a); guard(b) -> guard(a & b).
-      Instruction* MoveI = II->getNextNode();
+      Instruction* MoveI = II->getNextNonDebugInstruction();
       while (MoveI != NextInst) {
         auto *Temp = MoveI;
-        MoveI = MoveI->getNextNode();
+        MoveI = MoveI->getNextNonDebugInstruction();
         Temp->moveBefore(II);
       }
       II->setArgOperand(0, Builder.CreateAnd(CurrCond, NextCond));
Index: llvm/test/Transforms/InstCombine/call-guard-dbg.ll
===================================================================
--- /dev/null
+++ llvm/test/Transforms/InstCombine/call-guard-dbg.ll
@@ -0,0 +1,38 @@
+; RUN: opt < %s -instcombine -S -debugify-each | FileCheck %s
+
+declare void @llvm.experimental.guard(i1, ...)
+
+; This version tests for the common form where the conditions are
+; between the guards
+define void @test_guard_adjacent_diff_cond2(i32 %V1, i32 %V2) {
+; CHECK-LABEL: @test_guard_adjacent_diff_cond2(
+; CHECK-NEXT:    %1 = and i32 %V1, %V2
+; CHECK-NEXT:    %2 = icmp slt i32 %1, 0
+; CHECK-NEXT:    %and = and i32 %V1, 255
+; CHECK-NEXT:    %C = icmp ult i32 %and, 129
+; CHECK-NEXT:    %3 = and i1 %2, %C
+; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 %3, i32 123) [ "deopt"() ]
+; CHECK-NEXT:    ret void
+  %A = icmp slt i32 %V1, 0
+  call void(i1, ...) @llvm.experimental.guard( i1 %A, i32 123 )[ "deopt"() ]
+  %B = icmp slt i32 %V2, 0
+  call void(i1, ...) @llvm.experimental.guard( i1 %B, i32 456 )[ "deopt"() ]
+  %and = and i32 %V1, 255
+  %C = icmp sle i32 %and, 128
+  call void(i1, ...) @llvm.experimental.guard( i1 %C, i32 789 )[ "deopt"() ]
+  ret void
+}
+
+define void @deref_load(i32 %V1, i32* dereferenceable(4) %P) {
+; CHECK-LABEL: @deref_load
+; CHECK-NEXT:  %V2 = load i32, i32* %P, align 4
+; CHECK-NEXT:  %1 = and i32 %V2, %V1
+; CHECK-NEXT:  %2 = icmp slt i32 %1, 0
+; CHECK-NEXT:  call void (i1, ...) @llvm.experimental.guard(i1 %2, i32 123) [ "deopt"() ]
+  %A = icmp slt i32 %V1, 0
+  call void(i1, ...) @llvm.experimental.guard( i1 %A, i32 123 )[ "deopt"() ]
+  %V2 = load i32, i32* %P
+  %B = icmp slt i32 %V2, 0
+  call void(i1, ...) @llvm.experimental.guard( i1 %B, i32 456 )[ "deopt"() ]
+  ret void
+}