1 files changed, 76 insertions, 0 deletions
diff --git a/test/Transforms/LICM/lcssa-ssa-promoter.ll b/test/Transforms/LICM/lcssa-ssa-promoter.ll
new file mode 100644
index 0000000000..5df3ef1218
--- /dev/null
+++ b/test/Transforms/LICM/lcssa-ssa-promoter.ll
@@ -0,0 +1,76 @@
+; RUN: opt -S -basicaa -licm < %s | FileCheck %s
+;
+; Manually validate LCSSA form is preserved even after SSAUpdater is used to
+; promote things in the loop bodies.
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@x = common global i32 0, align 4
+@y = common global i32 0, align 4
+
+define void @PR18688() {
+; CHECK-LABEL: @PR18688(
+
+entry:
+  br i1 undef, label %return, label %outer.preheader
+
+outer.preheader:
+  br label %outer.header
+; CHECK: outer.preheader:
+; CHECK: br label %outer.header
+
+outer.header:
+  store i32 0, i32* @x, align 4
+  br i1 undef, label %outer.latch, label %inner.preheader
+; CHECK: outer.header:
+; CHECK-NEXT: br i1 undef, label %outer.latch, label %inner.preheader
+
+inner.preheader:
+  br label %inner.header
+; CHECK: inner.preheader:
+; CHECK-NEXT: br label %inner.header
+
+inner.header:
+  br i1 undef, label %inner.body.rhs, label %inner.latch
+; CHECK: inner.header:
+; CHECK-NEXT: %[[PHI0:[^,]+]] = phi i32 [ %{{[^,]+}}, %inner.latch ], [ 0, %inner.preheader ]
+; CHECK-NEXT: br i1 undef, label %inner.body.rhs, label %inner.latch
+
+inner.body.rhs:
+  store i32 0, i32* @x, align 4
+  br label %inner.latch
+; CHECK: inner.body.rhs:
+; CHECK-NEXT: br label %inner.latch
+
+inner.latch:
+  %y_val = load i32* @y, align 4
+  %icmp = icmp eq i32 %y_val, 0
+  br i1 %icmp, label %inner.exit, label %inner.header
+; CHECK: inner.latch:
+; CHECK-NEXT: %[[PHI1:[^,]+]] = phi i32 [ 0, %inner.body.rhs ], [ %[[PHI0]], %inner.header ]
+; CHECK-NEXT: br i1 %{{[^,]+}}, label %inner.exit, label %inner.header
+
+inner.exit:
+  br label %outer.latch
+; CHECK: inner.exit:
+; CHECK-NEXT: %[[INNER_LCSSA:[^,]+]] = phi i32 [ %[[PHI1]], %inner.latch ]
+; CHECK-NEXT: br label %outer.latch
+
+outer.latch:
+  br i1 undef, label %outer.exit, label %outer.header
+; CHECK: outer.latch:
+; CHECK-NEXT: %[[PHI2:[^,]+]] = phi i32 [ %[[INNER_LCSSA]], %inner.exit ], [ 0, %outer.header ]
+; CHECK-NEXT: br i1 {{.*}}, label %outer.exit, label %outer.header
+
+outer.exit:
+  br label %return
+; CHECK: outer.exit:
+; CHECK-NEXT: %[[OUTER_LCSSA:[^,]+]] = phi i32 [ %[[PHI2]], %outer.latch ]
+; CHECK-NEXT: store i32 %[[OUTER_LCSSA]]
+; CHECK-NEXT: br label %return
+
+return:
+  ret void
+}
+