[llvm] r296962 - Add test missed in r296770.

[Evgeny Stupachenko via llvm-commits]

Author: evstupac
Date: Fri Mar  3 23:20:02 2017
New Revision: 296962

URL: http://llvm.org/viewvc/llvm-project?rev=296962&view=rev
Log:
Add test missed in r296770.

Differential Revision: http://reviews.llvm.org/D27004

From: Evgeny Stupachenko <evstupac at gmail.com>

Added:
    llvm/trunk/test/Transforms/LoopUnroll/epilog_const_phi.ll

Added: llvm/trunk/test/Transforms/LoopUnroll/epilog_const_phi.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopUnroll/epilog_const_phi.ll?rev=296962&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/LoopUnroll/epilog_const_phi.ll (added)
+++ llvm/trunk/test/Transforms/LoopUnroll/epilog_const_phi.ll Fri Mar  3 23:20:02 2017
@@ -0,0 +1,65 @@
+; RUN: opt -S -loop-unroll -unroll-runtime < %s | FileCheck %s
+
+; Epilog unroll allows to keep PHI constant value.
+; For the test this means that after unroll XOR could be deleted.
+; Check that we do epilogue reminder here.
+
+; CHECK-LABEL: const_phi_val
+; CHECK:  for.body.epil
+
+; Function Attrs: norecurse nounwind uwtable
+define void @const_phi_val(i32 %i0, i32* nocapture %a) {
+entry:
+  %cmp6 = icmp slt i32 %i0, 1000
+  br i1 %cmp6, label %for.body.preheader, label %for.end
+
+for.body.preheader:                               ; preds = %entry
+  %tmp = sext i32 %i0 to i64
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %for.body.preheader
+  %indvars.iv = phi i64 [ %tmp, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
+  %s.08 = phi i32 [ 0, %for.body.preheader ], [ %xor, %for.body ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
+  store i32 %s.08, i32* %arrayidx, align 4
+  %xor = xor i32 %s.08, 1
+  %indvars.iv.next = add nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 1000
+  br i1 %exitcond, label %for.end.loopexit, label %for.body
+
+for.end.loopexit:                                 ; preds = %for.body
+  br label %for.end
+
+for.end:                                          ; preds = %for.end.loopexit, %entry
+  ret void
+}
+
+; When there is no phi with const coming from preheader,
+; there is no need to do epilogue unrolling.
+
+; CHECK-LABEL: var_phi_val
+; CHECK:  for.body.prol
+
+; Function Attrs: norecurse nounwind uwtable
+define void @var_phi_val(i32 %i0, i32* nocapture %a) {
+entry:
+  %cmp6 = icmp slt i32 %i0, 1000
+  br i1 %cmp6, label %for.body.preheader, label %for.end
+
+for.body.preheader:                               ; preds = %entry
+  %tmp = sext i32 %i0 to i64
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %for.body.preheader
+  %indvars.iv = phi i64 [ %tmp, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
+  %indvars.iv.next = add nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 1000
+  br i1 %exitcond, label %for.end.loopexit, label %for.body
+
+for.end.loopexit:                                 ; preds = %for.body
+  br label %for.end
+
+for.end:                                          ; preds = %for.end.loopexit, %entry
+  ret void
+}