1 files changed, 36 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopStrengthReduce/sext-ind-var.ll b/llvm/test/Transforms/LoopStrengthReduce/sext-ind-var.ll
new file mode 100644
index 00000000000..9fca3f97094
--- /dev/null
+++ b/llvm/test/Transforms/LoopStrengthReduce/sext-ind-var.ll
@@ -0,0 +1,36 @@
+; RUN: opt -loop-reduce -S < %s | FileCheck %s
+
+target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64"
+target triple = "nvptx64-unknown-unknown"
+
+; LSR used not to be able to generate a float* induction variable in
+; these cases due to scalar evolution not propagating nsw from an
+; instruction to the SCEV, preventing distributing sext into the
+; corresponding addrec.
+
+define float @testadd(float* %input, i32 %offset, i32 %numIterations) {
+; CHECK-LABEL: @testadd
+; CHECK: sext i32 %offset to i64
+; CHECK: loop:
+; CHECK-DAG: phi float*
+; CHECK-DAG: phi i32
+; CHECK-NOT: sext
+
+entry:
+  br label %loop
+
+loop:
+  %i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
+  %sum = phi float [ %nextsum, %loop ], [ 0.000000e+00, %entry ]
+  %index32 = add nuw nsw i32 %i, %offset
+  %index64 = sext i32 %index32 to i64
+  %ptr = getelementptr inbounds float, float* %input, i64 %index64
+  %addend = load float, float* %ptr, align 4
+  %nextsum = fadd float %sum, %addend
+  %nexti = add nuw nsw i32 %i, 1
+  %exitcond = icmp eq i32 %nexti, %numIterations
+  br i1 %exitcond, label %exit, label %loop
+
+exit:
+  ret float %nextsum
+}