[llvm] f2ada6d - [VPlan] Add test for convertToStridedAccess flag issue. NFC (#209425)

[via llvm-commits]

Author: Luke Lau
Date: 2026-07-14T18:07:56+08:00
New Revision: f2ada6d997fe4f4854f15f2c880dd740cd2ebb8a

URL: https://github.com/llvm/llvm-project/commit/f2ada6d997fe4f4854f15f2c880dd740cd2ebb8a
DIFF: https://github.com/llvm/llvm-project/commit/f2ada6d997fe4f4854f15f2c880dd740cd2ebb8a.diff

LOG: [VPlan] Add test for convertToStridedAccess flag issue. NFC (#209425)

>From the comment in
https://github.com/llvm/llvm-project/pull/209168/changes#r3574524959

Added: 
    llvm/test/Transforms/LoopVectorize/RISCV/strided-accesses-unroll.ll

Modified: 
    

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/LoopVectorize/RISCV/strided-accesses-unroll.ll b/llvm/test/Transforms/LoopVectorize/RISCV/strided-accesses-unroll.ll
new file mode 100644
index 0000000000000..c4727847d244f
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/RISCV/strided-accesses-unroll.ll
@@ -0,0 +1,61 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --filter-out-after "^scalar.ph" --version 6
+; RUN: opt < %s -S -p loop-vectorize -mtriple riscv64 -mattr=+v -force-vector-interleave=2 | FileCheck %s
+
+; FIXME: the second part of the strided load's gep shouldn't have nuw.
+
+define void @negative_stride_nuw(ptr noalias %src, ptr noalias %dst) {
+; CHECK-LABEL: define void @negative_stride_nuw(
+; CHECK-SAME: ptr noalias [[SRC:%.*]], ptr noalias [[DST:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[TMP0:%.*]] = call i64 @llvm.vscale.i64()
+; CHECK-NEXT:    [[TMP1:%.*]] = shl nuw i64 [[TMP0]], 3
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 512, [[TMP1]]
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
+; CHECK:       [[VECTOR_PH]]:
+; CHECK-NEXT:    [[TMP2:%.*]] = shl nuw i64 [[TMP0]], 2
+; CHECK-NEXT:    [[TMP3:%.*]] = shl nuw i64 [[TMP2]], 1
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 512, [[TMP3]]
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 512, [[N_MOD_VF]]
+; CHECK-NEXT:    [[TMP4:%.*]] = mul i64 [[N_VEC]], -2
+; CHECK-NEXT:    [[TMP5:%.*]] = add i64 1022, [[TMP4]]
+; CHECK-NEXT:    [[TMP6:%.*]] = trunc i64 [[TMP2]] to i32
+; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr nuw i8, ptr [[SRC]], i64 4088
+; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
+; CHECK:       [[VECTOR_BODY]]:
+; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[TMP8:%.*]] = mul i64 [[INDEX]], -8
+; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr i8, ptr [[TMP7]], i64 [[TMP8]]
+; CHECK-NEXT:    [[TMP10:%.*]] = mul i64 [[TMP2]], -8
+; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr nuw i8, ptr [[TMP9]], i64 [[TMP10]]
+; CHECK-NEXT:    [[TMP12:%.*]] = call <vscale x 4 x i32> @llvm.experimental.vp.strided.load.nxv4i32.p0.i64(ptr align 4 [[TMP9]], i64 -8, <vscale x 4 x i1> splat (i1 true), i32 [[TMP6]])
+; CHECK-NEXT:    [[TMP13:%.*]] = call <vscale x 4 x i32> @llvm.experimental.vp.strided.load.nxv4i32.p0.i64(ptr align 4 [[TMP11]], i64 -8, <vscale x 4 x i1> splat (i1 true), i32 [[TMP6]])
+; CHECK-NEXT:    [[TMP14:%.*]] = getelementptr inbounds i32, ptr [[DST]], i64 [[INDEX]]
+; CHECK-NEXT:    [[TMP15:%.*]] = getelementptr inbounds i32, ptr [[TMP14]], i64 [[TMP2]]
+; CHECK-NEXT:    store <vscale x 4 x i32> [[TMP12]], ptr [[TMP14]], align 4
+; CHECK-NEXT:    store <vscale x 4 x i32> [[TMP13]], ptr [[TMP15]], align 4
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], [[TMP3]]
+; CHECK-NEXT:    [[TMP16:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP16]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       [[MIDDLE_BLOCK]]:
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 512, [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], [[EXIT:label %.*]], label %[[SCALAR_PH]]
+; CHECK:       [[SCALAR_PH]]:
+;
+entry:
+  br label %loop
+
+loop:
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
+  %iv2 = phi i64 [ 1022, %entry ], [ %iv2.next, %loop ]
+  %gep.src = getelementptr nuw i32, ptr %src, i64 %iv2
+  %x = load i32, ptr %gep.src
+  %gep.dst = getelementptr inbounds i32, ptr %dst, i64 %iv
+  store i32 %x, ptr %gep.dst
+  %iv2.next = add nsw i64 %iv2, -2
+  %iv.next = add nuw nsw i64 %iv, 1
+  %ec = icmp eq i64 %iv.next, 512
+  br i1 %ec, label %exit, label %loop
+
+exit:
+  ret void
+}