From cee313d288a4faf0355d76fb6e0e927e211d08a5 Mon Sep 17 00:00:00 2001
From: Eric Christopher <echristo@gmail.com>
Date: Wed, 17 Apr 2019 04:52:47 +0000
Subject: Revert "Temporarily Revert "Add basic loop fusion pass.""

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
---
 .../Transforms/SimplifyCFG/switch_switch_fold.ll   | 65 ++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 llvm/test/Transforms/SimplifyCFG/switch_switch_fold.ll

(limited to 'llvm/test/Transforms/SimplifyCFG/switch_switch_fold.ll')

diff --git a/llvm/test/Transforms/SimplifyCFG/switch_switch_fold.ll b/llvm/test/Transforms/SimplifyCFG/switch_switch_fold.ll
new file mode 100644
index 00000000000..7f6f1c94bd4
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyCFG/switch_switch_fold.ll
@@ -0,0 +1,65 @@
+; RUN: opt < %s -simplifycfg -S | FileCheck %s
+
+; Test that a switch going to a switch on the same value can be merged.
+; All three switches in this example can be merged into one big one.
+
+declare void @foo1()
+
+declare void @foo2()
+
+declare void @foo3()
+
+declare void @foo4()
+
+define void @test1(i32 %V) {
+        switch i32 %V, label %F [
+                 i32 4, label %T
+                 i32 17, label %T
+                 i32 5, label %T
+                 i32 1234, label %F
+        ]
+T:              ; preds = %0, %0, %0
+        switch i32 %V, label %F [
+                 i32 4, label %A
+                 i32 17, label %B
+                 i32 42, label %C
+        ]
+A:              ; preds = %T
+        call void @foo1( )
+        ret void
+B:              ; preds = %F, %F, %T
+        call void @foo2( )
+        ret void
+C:              ; preds = %T
+        call void @foo3( )
+        ret void
+F:              ; preds = %F, %T, %0, %0
+        switch i32 %V, label %F [
+                 i32 4, label %B
+                 i32 18, label %B
+                 i32 42, label %D
+        ]
+D:              ; preds = %F
+        call void @foo4( )
+        ret void
+
+; CHECK-LABEL: @test1(
+; CHECK-NEXT:    switch i32 %V, label %infloop [
+; CHECK-NEXT:    i32 4, label %A
+; CHECK-NEXT:    i32 17, label %B
+; CHECK-NEXT:    i32 18, label %B
+; CHECK-NEXT:    i32 42, label %D
+; CHECK-NEXT:    ]
+; CHECK:       A:
+; CHECK-NEXT:    call void @foo1()
+; CHECK-NEXT:    ret void
+; CHECK:       B:
+; CHECK-NEXT:    call void @foo2()
+; CHECK-NEXT:    ret void
+; CHECK:       D:
+; CHECK-NEXT:    call void @foo4()
+; CHECK-NEXT:    ret void
+; CHECK:       infloop:
+; CHECK-NEXT:    br label %infloop
+}
+
-- 
cgit v1.2.3