[GISel][CombinerHelper] Add a combine turning shuffle_vector into concat_vectors

Teach the CombinerHelper how to turn shuffle_vectors, that
concatenate vectors, into concat_vectors and add this combine
to the AArch64 pre-legalizer combiner.

Differential Revision: https://reviews.llvm.org/D69149

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@375452 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 353 insertions, 0 deletions

diff --git a/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-shuffle-vector.mir b/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-shuffle-vector.mir
new file mode 100644
index 00000000000..e3a27aa2b16
--- /dev/null
+++ b/test/CodeGen/AArch64/GlobalISel/prelegalizercombiner-shuffle-vector.mir
@@ -0,0 +1,353 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -mtriple aarch64-apple-ios  -run-pass=aarch64-prelegalizer-combiner %s -o - | FileCheck %s
+
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(0,1,2,3))
+# into concat_vector(Src1, Src2).
+---
+name: shuffle_vector_to_concat_vector_0123
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_0123
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<4 x s32>) = G_CONCAT_VECTORS [[COPY]](<2 x s32>), [[COPY1]](<2 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<4 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<4 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(0, 1, 2, 3)
+    RET_ReallyLR implicit %2
+...
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(2,3,0,1,2,3))
+# into concat_vector(Src2, Src1, Src2).
+---
+name: shuffle_vector_to_concat_vector_230123
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_230123
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<6 x s32>) = G_CONCAT_VECTORS [[COPY1]](<2 x s32>), [[COPY]](<2 x s32>), [[COPY1]](<2 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<6 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<6 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(2,3,0,1,2,3)
+    RET_ReallyLR implicit %2
+...
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(2,undef,0,1,undef,3))
+# into concat_vector(Src2, Src1, Src2).
+---
+name: shuffle_vector_to_concat_vector_2undef01undef3
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_2undef01undef3
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<6 x s32>) = G_CONCAT_VECTORS [[COPY1]](<2 x s32>), [[COPY]](<2 x s32>), [[COPY1]](<2 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<6 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<6 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(2,-1,0,1,-1,3)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# when the sources get half mixed.
+---
+name: shuffle_vector_to_concat_vector_mixed_src_200123_neg
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_mixed_src_200123_neg
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<6 x s32>) = G_SHUFFLE_VECTOR [[COPY]](<2 x s32>), [[COPY1]], shufflemask(2, 0, 0, 1, 2, 3)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<6 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<6 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(2,0,0,1,2,3)
+    RET_ReallyLR implicit %2
+...
+# Check that we produce implicit_def while canonicalizing shuffle_vector(Src1, Src2, mask(2,undef,undef,undef,undef,1))
+# into concat_vector(Src2, undef, Src1).
+---
+name: shuffle_vector_to_concat_vector_2undef1
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_2undef1
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[DEF:%[0-9]+]]:_(<2 x s32>) = G_IMPLICIT_DEF
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<6 x s32>) = G_CONCAT_VECTORS [[COPY1]](<2 x s32>), [[DEF]](<2 x s32>), [[COPY]](<2 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<6 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<6 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(2,-1,-1,-1,-1,1)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# if a source is flipped.
+---
+name: shuffle_vector_to_concat_vector_src_flipped_230132_neg
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_src_flipped_230132_neg
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<6 x s32>) = G_SHUFFLE_VECTOR [[COPY]](<2 x s32>), [[COPY1]], shufflemask(2, 3, 0, 1, 3, 2)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<6 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<6 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(2,3,0,1,3,2)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# if a source is flipped and the other half is undef.
+---
+name: shuffle_vector_to_concat_vector_src_flipped_23013undef_neg
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $d0, $d1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_src_flipped_23013undef_neg
+    ; CHECK: liveins: $d0, $d1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<2 x s32>) = COPY $d0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<2 x s32>) = COPY $d1
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<6 x s32>) = G_SHUFFLE_VECTOR [[COPY]](<2 x s32>), [[COPY1]], shufflemask(2, 3, 0, 1, 3, -1)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<6 x s32>)
+    %0:_(<2 x s32>) = COPY $d0
+    %1:_(<2 x s32>) = COPY $d1
+    %2:_(<6 x s32>) = G_SHUFFLE_VECTOR %0(<2 x s32>), %1(<2 x s32>), shufflemask(2,3,0,1,3,-1)
+    RET_ReallyLR implicit %2
+...
+
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(0,1,2,3,4,5,6,7))
+# into concat_vector(Src1, Src2) with bigger vector type.
+---
+name: shuffle_vector_to_concat_vector_01234567
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_01234567
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<8 x s32>) = G_CONCAT_VECTORS [[COPY]](<4 x s32>), [[COPY1]](<4 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<8 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<8 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(0, 1, 2, 3, 4, 5, 6, 7)
+    RET_ReallyLR implicit %2
+...
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(4,5,6,7,0,1,2,3))
+# into concat_vector(Src2, Src1, Src2) with bigger vector type.
+---
+name: shuffle_vector_to_concat_vector_45670123
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_45670123
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<12 x s32>) = G_CONCAT_VECTORS [[COPY1]](<4 x s32>), [[COPY]](<4 x s32>), [[COPY1]](<4 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<12 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<12 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(4,5,6,7,0,1,2,3,4,5,6,7)
+    RET_ReallyLR implicit %2
+...
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(4,5,undef,undef,0,1,2,3,undef,undef,6,7))
+# into concat_vector(Src2, Src1, Src2) with bigger vector type.
+---
+name: shuffle_vector_to_concat_vector_45undefundef0123undefundef67
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_45undefundef0123undefundef67
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<12 x s32>) = G_CONCAT_VECTORS [[COPY1]](<4 x s32>), [[COPY]](<4 x s32>), [[COPY1]](<4 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<12 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<12 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(4,5,-1,-1,0,1,2,3,-1,-1,6,7)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# when the sources get half mixed with bigger vector type.
+---
+name: shuffle_vector_to_concat_vector_mixed_src_456000123_neg
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_mixed_src_456000123_neg
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<8 x s32>) = G_SHUFFLE_VECTOR [[COPY]](<4 x s32>), [[COPY1]], shufflemask(4, 5, 6, 0, 0, 1, 2, 3)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<8 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<8 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(4,5,6,0,0,1,2,3)
+    RET_ReallyLR implicit %2
+...
+# Check that we produce implicit_def while canonicalizing shuffle_vector(Src1, Src2, mask(2,undef,undef,undef,undef,1))
+# into concat_vector(Src2, undef, Src1) with bigger vector type.
+---
+name: shuffle_vector_to_concat_vector_45undefundefundefundefundefundefundefundef23
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_45undefundefundefundefundefundefundefundef23
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[DEF:%[0-9]+]]:_(<4 x s32>) = G_IMPLICIT_DEF
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<12 x s32>) = G_CONCAT_VECTORS [[COPY1]](<4 x s32>), [[DEF]](<4 x s32>), [[COPY]](<4 x s32>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<12 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<12 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(4,5,-1,-1,-1,-1,-1,-1,-1,-1,2,3)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# when we grab less than the full vectors.
+---
+name: shuffle_vector_to_concat_vector_4501_neg
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_4501_neg
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<4 x s32>) = G_SHUFFLE_VECTOR [[COPY]](<4 x s32>), [[COPY1]], shufflemask(4, 5, 0, 1)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<4 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<4 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(4,5,0,1)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# if a source is flipped and the other half is undef with bigger vector.
+---
+name: shuffle_vector_to_concat_vector_src_flipped_4567012367undefundef_neg
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0, $q1
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_src_flipped_4567012367undefundef_neg
+    ; CHECK: liveins: $q0, $q1
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x s32>) = COPY $q0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x s32>) = COPY $q1
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<12 x s32>) = G_SHUFFLE_VECTOR [[COPY]](<4 x s32>), [[COPY1]], shufflemask(4, 5, 6, 7, 0, 1, 2, 3, 6, 7, -1, -1)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<12 x s32>)
+    %0:_(<4 x s32>) = COPY $q0
+    %1:_(<4 x s32>) = COPY $q1
+    %2:_(<12 x s32>) = G_SHUFFLE_VECTOR %0(<4 x s32>), %1(<4 x s32>), shufflemask(4,5,6,7,0,1,2,3,6,7,-1,-1)
+    RET_ReallyLR implicit %2
+...
+# Check that we canonicalize shuffle_vector(Src1, Src2, mask(4,5,undef,undef,0,1,2,3,undef,undef,6,7))
+# into concat_vector(Src2, Src1, Src2) with vector of pointers.
+---
+name: shuffle_vector_to_concat_vector_45undefundef0123undefundef67_ptr
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0_q1, $q2_q3
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_45undefundef0123undefundef67_ptr
+    ; CHECK: liveins: $q0_q1, $q2_q3
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x p0>) = COPY $q0_q1
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x p0>) = COPY $q2_q3
+    ; CHECK: [[CONCAT_VECTORS:%[0-9]+]]:_(<12 x p0>) = G_CONCAT_VECTORS [[COPY1]](<4 x p0>), [[COPY]](<4 x p0>), [[COPY1]](<4 x p0>)
+    ; CHECK: RET_ReallyLR implicit [[CONCAT_VECTORS]](<12 x p0>)
+    %0:_(<4 x p0>) = COPY $q0_q1
+    %1:_(<4 x p0>) = COPY $q2_q3
+    %2:_(<12 x p0>) = G_SHUFFLE_VECTOR %0(<4 x p0>), %1(<4 x p0>), shufflemask(4,5,-1,-1,0,1,2,3,-1,-1,6,7)
+    RET_ReallyLR implicit %2
+...
+# Check that we don't canonicalize shuffle_vector into concat_vectors
+# when the sources get half mixed with vector of pointers.
+---
+name: shuffle_vector_to_concat_vector_mixed_src_456000123_neg_ptr
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $q0_q1, $q2_q3
+
+    ; CHECK-LABEL: name: shuffle_vector_to_concat_vector_mixed_src_456000123_neg_ptr
+    ; CHECK: liveins: $q0_q1, $q2_q3
+    ; CHECK: [[COPY:%[0-9]+]]:_(<4 x p0>) = COPY $q0_q1
+    ; CHECK: [[COPY1:%[0-9]+]]:_(<4 x p0>) = COPY $q2_q3
+    ; CHECK: [[SHUF:%[0-9]+]]:_(<8 x p0>) = G_SHUFFLE_VECTOR [[COPY]](<4 x p0>), [[COPY1]], shufflemask(4, 5, 6, 0, 0, 1, 2, 3)
+    ; CHECK: RET_ReallyLR implicit [[SHUF]](<8 x p0>)
+    %0:_(<4 x p0>) = COPY $q0_q1
+    %1:_(<4 x p0>) = COPY $q2_q3
+    %2:_(<8 x p0>) = G_SHUFFLE_VECTOR %0(<4 x p0>), %1(<4 x p0>), shufflemask(4,5,6,0,0,1,2,3)
+    RET_ReallyLR implicit %2
+...
+
+# Check that shuffle_vector gets combined into concat_vectors then the
+# concat_vectors gets combined into build_vector.
+---
+name: shuffle_vector_to_build_vector_ptr
+tracksRegLiveness: true
+body:             |
+  bb.1:
+    liveins: $x0, $x1, $x2, $x3
+
+    ; CHECK-LABEL: name: shuffle_vector_to_build_vector_ptr
+    ; CHECK: liveins: $x0, $x1, $x2, $x3
+    ; CHECK: [[COPY:%[0-9]+]]:_(p0) = COPY $x0
+    ; CHECK: [[COPY1:%[0-9]+]]:_(p0) = COPY $x1
+    ; CHECK: [[COPY2:%[0-9]+]]:_(p0) = COPY $x2
+    ; CHECK: [[COPY3:%[0-9]+]]:_(p0) = COPY $x3
+    ; CHECK: [[BUILD_VECTOR:%[0-9]+]]:_(<4 x p0>) = G_BUILD_VECTOR [[COPY]](p0), [[COPY1]](p0), [[COPY2]](p0), [[COPY3]](p0)
+    ; CHECK: RET_ReallyLR implicit [[BUILD_VECTOR]](<4 x p0>)
+    %0:_(p0) = COPY $x0
+    %1:_(p0) = COPY $x1
+    %2:_(p0) = COPY $x2
+    %3:_(p0) = COPY $x3
+    %4:_(<2 x p0>) = G_BUILD_VECTOR %0(p0), %1
+    %5:_(<2 x p0>) = G_BUILD_VECTOR %2(p0), %3
+    %6:_(<4 x p0>) = G_SHUFFLE_VECTOR %4(<2 x p0>), %5(<2 x p0>), shufflemask(0,1,2,3)
+    RET_ReallyLR implicit %6
+...