[llvm] Handle IMPLICIT_DEF in TripleMBB for WindowScheduler (PR #179190)

[Ryotaro Kasuga via llvm-commits]

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@@ -0,0 +1,54 @@
+# RUN: llc -mtriple=hexagon -run-pass pipeliner %s -o - | FileCheck %s
+# REQUIRES: asserts
+# Ensure WindowScheduler copies IMPLICIT_DEF into the triple-MBB region
+# so LiveIntervals no longer hits LR.verify()
+# CHECK: foo
+
+--- |
+  define void @foo() {
+    ret void
+  }
+...
+
+---
+name:            foo
+tracksRegLiveness: true
+
+body:             |
+  bb.0:
+    successors: %bb.1(0x60000000), %bb.2(0x20000000)
+    liveins: $r0, $r1, $r2
+
+    %bb0_e75bf3f0bba6b3ae__1:hvxqr = IMPLICIT_DEF
----------------
kasuga-fj wrote:

Could you format the register names the same way as in the other tests? IIUC, they should look like `%0: hvxpr = ...`, and so on.


https://github.com/llvm/llvm-project/pull/179190