Generalize OptimizeLoopTermCond to optimize more loop terminating icmp to use postinc iv.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89116 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 27 insertions, 0 deletions

diff --git a/test/Transforms/LoopStrengthReduce/icmp_use_postinc.ll b/test/Transforms/LoopStrengthReduce/icmp_use_postinc.ll
new file mode 100644
index 0000000..4ad5d14
--- /dev/null
+++ b/test/Transforms/LoopStrengthReduce/icmp_use_postinc.ll
@@ -0,0 +1,27 @@
+; RUN: opt < %s -loop-reduce -S | FileCheck %s
+
+define i32 @main(i32 %argc, i8** nocapture %argv) nounwind ssp {
+entry:
+  br i1 undef, label %bb4.preheader, label %bb.nph8
+
+bb4.preheader:                                    ; preds = %entry
+  br label %bb4
+
+bb1:                                              ; preds = %bb4
+  br i1 undef, label %bb.nph8, label %bb3
+
+bb3:                                              ; preds = %bb1
+  %phitmp = add i32 %indvar, 1                    ; <i32> [#uses=1]
+  br label %bb4
+
+bb4:                                              ; preds = %bb3, %bb4.preheader
+; CHECK: %lsr.iv = phi
+; CHECK: %lsr.iv.next = add i32 %lsr.iv, 1
+; CHECK: %0 = icmp slt i32 %lsr.iv.next, %argc
+  %indvar = phi i32 [ 1, %bb4.preheader ], [ %phitmp, %bb3 ] ; <i32> [#uses=2]
+  %0 = icmp slt i32 %indvar, %argc                ; <i1> [#uses=1]
+  br i1 %0, label %bb1, label %bb.nph8
+
+bb.nph8:                                          ; preds = %bb4, %bb1, %entry
+  unreachable
+}