1 files changed, 27 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/RISCV/pr40333.ll b/llvm/test/CodeGen/RISCV/pr40333.ll
new file mode 100644
index 00000000000..3f7ae8da3a2
--- /dev/null
+++ b/llvm/test/CodeGen/RISCV/pr40333.ll
@@ -0,0 +1,27 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=riscv64 -verify-machineinstrs < %s \
+; RUN:   | FileCheck -check-prefix=RV64I %s
+
+; This test case is significantly simplified from the submitted .ll but
+; demonstrates the same issue. At the time of this problem report, an infinite
+; loop would be created in DAGCombine, converting ANY_EXTEND to SIGN_EXTEND
+; and back again.
+
+; TODO: This test case is also an example of where it would be cheaper to
+; select SRLW, but the current lowering strategy fails to do so.
+
+define signext i8 @foo(i32 %a, i32 %b) nounwind {
+; RV64I-LABEL: foo:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    slli a1, a1, 32
+; RV64I-NEXT:    srli a1, a1, 32
+; RV64I-NEXT:    slli a0, a0, 32
+; RV64I-NEXT:    srli a0, a0, 32
+; RV64I-NEXT:    srl a0, a0, a1
+; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srai a0, a0, 56
+; RV64I-NEXT:    ret
+ %1 = lshr i32 %a, %b
+ %2 = trunc i32 %1 to i8
+ ret i8 %2
+}