1 files changed, 86 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/SystemZ/rot-02.ll b/llvm/test/CodeGen/SystemZ/rot-02.ll
new file mode 100644
index 00000000000..12b09f13185
--- /dev/null
+++ b/llvm/test/CodeGen/SystemZ/rot-02.ll
@@ -0,0 +1,86 @@
+; Test removal of AND operations that don't affect last 6 bits of rotate amount
+; operand.
+;
+; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s
+
+; Test that AND is not removed when some lower 6 bits are not set.
+define i32 @f1(i32 %val, i32 %amt) {
+; CHECK-LABEL: f1:
+; CHECK: nil{{[lf]}} %r3, 31
+; CHECK: rll %r2, %r2, 0(%r3)
+  %and = and i32 %amt, 31
+
+  %inv = sub i32 32, %and
+  %parta = shl i32 %val, %and
+  %partb = lshr i32 %val, %inv
+
+  %rotl = or i32 %parta, %partb
+
+  ret i32 %rotl
+}
+
+; Test removal of AND mask with only bottom 6 bits set.
+define i32 @f2(i32 %val, i32 %amt) {
+; CHECK-LABEL: f2:
+; CHECK-NOT: nil{{[lf]}} %r3, 63
+; CHECK: rll %r2, %r2, 0(%r3)
+  %and = and i32 %amt, 63
+
+  %inv = sub i32 32, %and
+  %parta = shl i32 %val, %and
+  %partb = lshr i32 %val, %inv
+
+  %rotl = or i32 %parta, %partb
+
+  ret i32 %rotl
+}
+
+; Test removal of AND mask including but not limited to bottom 6 bits.
+define i32 @f3(i32 %val, i32 %amt) {
+; CHECK-LABEL: f3:
+; CHECK-NOT: nil{{[lf]}} %r3, 255
+; CHECK: rll %r2, %r2, 0(%r3)
+  %and = and i32 %amt, 255
+
+  %inv = sub i32 32, %and
+  %parta = shl i32 %val, %and
+  %partb = lshr i32 %val, %inv
+
+  %rotl = or i32 %parta, %partb
+
+  ret i32 %rotl
+}
+
+; Test removal of AND mask from RLLG.
+define i64 @f4(i64 %val, i64 %amt) {
+; CHECK-LABEL: f4:
+; CHECK-NOT: nil{{[lf]}} %r3, 63
+; CHECK: rllg %r2, %r2, 0(%r3)
+  %and = and i64 %amt, 63
+
+  %inv = sub i64 64, %and
+  %parta = shl i64 %val, %and
+  %partb = lshr i64 %val, %inv
+
+  %rotl = or i64 %parta, %partb
+
+  ret i64 %rotl
+}
+
+; Test that AND is not entirely removed if the result is reused.
+define i32 @f5(i32 %val, i32 %amt) {
+; CHECK-LABEL: f5:
+; CHECK: rll %r2, %r2, 0(%r3)
+; CHECK: nil{{[lf]}} %r3, 63
+; CHECK: ar %r2, %r3
+  %and = and i32 %amt, 63
+
+  %inv = sub i32 32, %and
+  %parta = shl i32 %val, %and
+  %partb = lshr i32 %val, %inv
+
+  %rotl = or i32 %parta, %partb
+
+  %reuse = add i32 %and, %rotl
+  ret i32 %reuse
+}