Vendor import of llvm trunk r154661:

http://llvm.org/svn/llvm-project/llvm/trunk@r154661

1 files changed, 39 insertions, 0 deletions

diff --git a/test/Transforms/SimplifyCFG/multiple-phis.ll b/test/Transforms/SimplifyCFG/multiple-phis.ll
new file mode 100644
index 0000000..7845423
--- /dev/null
+++ b/test/Transforms/SimplifyCFG/multiple-phis.ll
@@ -0,0 +1,39 @@
+; RUN: opt -simplifycfg -S < %s | FileCheck %s
+
+; It's not worthwhile to if-convert one of the phi nodes and leave
+; the other behind, because that still requires a branch. If
+; SimplifyCFG if-converts one of the phis, it should do both.
+
+; CHECK:      %div.high.addr.0 = select i1 %cmp1, i32 %div, i32 %high.addr.0
+; CHECK-NEXT: %low.0.add2 = select i1 %cmp1, i32 %low.0, i32 %add2
+; CHECK-NEXT: br label %while.cond
+
+define i32 @upper_bound(i32* %r, i32 %high, i32 %k) nounwind {
+entry:
+  br label %while.cond
+
+while.cond:                                       ; preds = %if.then, %if.else, %entry
+  %high.addr.0 = phi i32 [ %high, %entry ], [ %div, %if.then ], [ %high.addr.0, %if.else ]
+  %low.0 = phi i32 [ 0, %entry ], [ %low.0, %if.then ], [ %add2, %if.else ]
+  %cmp = icmp ult i32 %low.0, %high.addr.0
+  br i1 %cmp, label %while.body, label %while.end
+
+while.body:                                       ; preds = %while.cond
+  %add = add i32 %low.0, %high.addr.0
+  %div = udiv i32 %add, 2
+  %idxprom = zext i32 %div to i64
+  %arrayidx = getelementptr inbounds i32* %r, i64 %idxprom
+  %0 = load i32* %arrayidx
+  %cmp1 = icmp ult i32 %k, %0
+  br i1 %cmp1, label %if.then, label %if.else
+
+if.then:                                          ; preds = %while.body
+  br label %while.cond
+
+if.else:                                          ; preds = %while.body
+  %add2 = add i32 %div, 1
+  br label %while.cond
+
+while.end:                                        ; preds = %while.cond
+  ret i32 %low.0
+}