diff --git a/llvm/lib/CodeGen/MachineSink.cpp b/llvm/lib/CodeGen/MachineSink.cpp
--- a/llvm/lib/CodeGen/MachineSink.cpp
+++ b/llvm/lib/CodeGen/MachineSink.cpp
@@ -695,9 +695,10 @@
       if (SuccToSinkTo) {
         // If a previous operand picked a block to sink to, then this operand
         // must be sinkable to the same block.
-        bool LocalUse = false;
-        if (!AllUsesDominatedByBlock(Reg, SuccToSinkTo, MBB,
-                                     BreakPHIEdge, LocalUse))
+        bool LocalUse = false, PrevBreakPHIEdge = BreakPHIEdge;
+        if (!AllUsesDominatedByBlock(Reg, SuccToSinkTo, MBB, BreakPHIEdge,
+                                     LocalUse) ||
+            BreakPHIEdge != PrevBreakPHIEdge)
           return nullptr;
 
         continue;
diff --git a/llvm/test/CodeGen/PowerPC/pr45557.mir b/llvm/test/CodeGen/PowerPC/pr45557.mir
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/pr45557.mir
@@ -0,0 +1,32 @@
+# RUN: llc -mtriple=powerpc -verify-machineinstrs -simplify-mir \
+# RUN:   --run-pass=machine-sink %s -o - | FileCheck %s
+
+--- |
+  @__const = external dso_local unnamed_addr constant [2 x i32], align 8
+  define void @c() {
+  entry:
+    unreachable
+  }
+...
+---
+name:            c
+alignment:       4
+tracksRegLiveness: true
+body:             |
+  bb.0:
+    %3:gprc_and_gprc_nor0 = LIS target-flags(ppc-ha) @__const
+    %0:gprc, %4:gprc_and_gprc_nor0 = LWZU target-flags(ppc-lo) @__const, %3 :: (load 4 from `i64* bitcast ([2 x i32]* @__const to i64*)`, align 8)
+    %5:crbitrc = IMPLICIT_DEF
+    BC killed %5, %bb.2
+    B %bb.1
+
+  bb.1:
+    %6:gprc = LI 0
+
+  bb.2:
+    %2:gprc = PHI %0, %bb.0, %6, %bb.1
+    %1:gprc = LWZ 4, killed %4 :: (dereferenceable load 4 from `i64* bitcast ([2 x i32]* @__const to i64*)` + 4, align 8)
+    BLR implicit $lr, implicit $rm
+...
+# CHECK-LABEL: bb.2:
+# CHECK-NOT:     LWZU