[llvm] [LoopFusion] Fix sink instructions (PR #147501)

[Ryotaro Kasuga via llvm-commits]

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@@ -988,8 +988,8 @@ struct LoopFuser {
 
             // If it is not safe to hoist/sink all instructions in the
             // pre-header, we cannot fuse these loops.
-            if (!collectMovablePreheaderInsts(*FC0, *FC1, SafeToHoist,
-                                              SafeToSink)) {
+            if (!collectAndFixMovablePreheaderInsts(*FC0, *FC1, SafeToHoist,
+                                                    SafeToSink)) {
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kasuga-fj wrote:

Sorry, I didn’t fully check the surrounding context, but considering what the each function is supposed to do, it might make more sense to call `fixPHINodes` in `movePreheaderInsts` (I'm not familiar enough to determine which is better...).

https://github.com/llvm/llvm-project/pull/147501