[llvm] [FileCheck] Add split view diff option for FileCheck (PR #189269)

[Henrik G. Olsson via llvm-commits]

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@@ -11,8 +13,13 @@ define void @foo() {
 ; CHECK-LABEL: define void @foo()
 ; CHECK:        call void @work_test()
 
-; DIFF:      @@ -[[#]] +[[#]] @@
-; DIFF:      define void @foo() {
-; DIFF-NEXT: -call void @work_test()
-; DIFF-NEXT: +call void @work_task()
-; DIFF-NEXT:  }
+; UNI:      @@ -[[#]] +[[#]] @@
+; UNI:      define void @foo() {
+; UNI-NEXT: -call void @work_test()
+; UNI-NEXT: +call void @work_task()
+; UNI-NEXT:  }
+
+; SPLIT:      @@ -[[#]] +[[#]] @@
+; SPLIT-NEXT: define void @foo() {              | define void @foo() {
+; SPLIT-NEXT: {{.*}}call void @work_test(){{.*}}|{{.*}}call void @work_task()
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hnrklssn wrote:

What are the globs for?

https://github.com/llvm/llvm-project/pull/189269