[llvm-branch-commits] [llvm] 21ce6cf - [RISCV] Add tests showing incorrect BUILD_VECTOR lowering

[Tom Stellard via llvm-branch-commits]

Author: Fraser Cormack
Date: 2022-04-25T20:27:35-07:00
New Revision: 21ce6cfd1d9357b54173d43e3d18960f487f6663

URL: https://github.com/llvm/llvm-project/commit/21ce6cfd1d9357b54173d43e3d18960f487f6663
DIFF: https://github.com/llvm/llvm-project/commit/21ce6cfd1d9357b54173d43e3d18960f487f6663.diff

LOG: [RISCV] Add tests showing incorrect BUILD_VECTOR lowering

These tests both use vector constants misidentified as VID sequences.
Because the initial run of elements has a zero step, the elements are
skipped until such a step can be identified. The bug is that the skipped
elements are never validated, even though the computed step is
incompatible across the entire sequence.

A fix will follow in a subseqeuent patch.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D123785

(cherry picked from commit 00537946aa29928894ba140687de1b6f9494e44d)

Added: 
    

Modified: 
    llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll b/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll
index 80c4ad8662b14..6fb669feb462a 100644
--- a/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll
+++ b/llvm/test/CodeGen/RISCV/rvv/fixed-vectors-int-buildvec.ll
@@ -704,3 +704,24 @@ define <8 x i16> @splat_idx_v8i16(<8 x i16> %v, i64 %idx) {
   %splat = shufflevector <8 x i16> %ins, <8 x i16> poison, <8 x i32> zeroinitializer
   ret <8 x i16> %splat
 }
+
+; FIXME: This is not a vid sequence!
+define <4 x i8> @buildvec_not_vid_v4i8_1() {
+; CHECK-LABEL: buildvec_not_vid_v4i8_1:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    vsetivli zero, 4, e8, mf4, ta, mu
+; CHECK-NEXT:    vid.v v8
+; CHECK-NEXT:    ret
+  ret <4 x i8> <i8 0, i8 0, i8 2, i8 3>
+}
+
+; FIXME: This is not a vid sequence!
+define <4 x i8> @buildvec_not_vid_v4i8_2() {
+; CHECK-LABEL: buildvec_not_vid_v4i8_2:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    vsetivli zero, 4, e8, mf4, ta, mu
+; CHECK-NEXT:    vid.v v8
+; CHECK-NEXT:    vrsub.vi v8, v8, 3
+; CHECK-NEXT:    ret
+  ret <4 x i8> <i8 3, i8 3, i8 1, i8 0>
+}