llvm-project/llvm/test/CodeGen/X86/vector-narrow-binop.ll

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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse2 | FileCheck %s --check-prefix=ALL --check-prefix=SSE --check-prefix=SSE2
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx | FileCheck %s --check-prefix=ALL --check-prefix=AVX --check-prefix=AVX1
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2 | FileCheck %s --check-prefix=ALL --check-prefix=AVX --check-prefix=AVX2
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512f | FileCheck %s --check-prefix=ALL --check-prefix=AVX --check-prefix=AVX512 --check-prefix=AVX512F
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512bw | FileCheck %s --check-prefix=ALL --check-prefix=AVX --check-prefix=AVX512 --check-prefix=AVX512BW
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512dq | FileCheck %s --check-prefix=ALL --check-prefix=AVX --check-prefix=AVX512 --check-prefix=AVX512DQ
; AVX1 has support for 256-bit bitwise logic because the FP variants were included.
; If using those ops requires extra insert/extract though, it's probably not worth it.
define <8 x i32> @PR32790(<8 x i32> %a, <8 x i32> %b, <8 x i32> %c, <8 x i32> %d) {
; SSE-LABEL: PR32790:
; SSE: # BB#0:
; SSE-NEXT: paddd %xmm2, %xmm0
; SSE-NEXT: paddd %xmm3, %xmm1
; SSE-NEXT: pand %xmm5, %xmm1
; SSE-NEXT: pand %xmm4, %xmm0
; SSE-NEXT: psubd %xmm6, %xmm0
; SSE-NEXT: psubd %xmm7, %xmm1
; SSE-NEXT: retq
;
; AVX1-LABEL: PR32790:
; AVX1: # BB#0:
[DAGCombiner] use narrow vector ops to eliminate concat/extract (PR32790) In the best case: extract (binop (concat X1, X2), (concat Y1, Y2)), N --> binop XN, YN ...we kill all of the extract/concat and just have narrow binops remaining. If only one of the binop operands is amenable, this transform is still worthwhile because we kill some of the extract/concat. Optional bitcasting makes the code more complicated, but there doesn't seem to be a way to avoid that. The TODO about extending to more than bitwise logic is there because we really will regress several x86 tests including madd, psad, and even a plain integer-multiply-by-2 or shift-left-by-1. I don't think there's anything fundamentally wrong with this patch that would cause those regressions; those folds are just missing or brittle. If we extend to more binops, I found that this patch will fire on at least one non-x86 regression test. There's an ARM NEON test in test/CodeGen/ARM/coalesce-subregs.ll with a pattern like: t5: v2f32 = vector_shuffle<0,3> t2, t4 t6: v1i64 = bitcast t5 t8: v1i64 = BUILD_VECTOR Constant:i64<0> t9: v2i64 = concat_vectors t6, t8 t10: v4f32 = bitcast t9 t12: v4f32 = fmul t11, t10 t13: v2i64 = bitcast t12 t16: v1i64 = extract_subvector t13, Constant:i32<0> There was no functional change in the codegen from this transform from what I could see though. For the x86 test changes: 1. PR32790() is the closest call. We don't reduce the AVX1 instruction count in that case, but we improve throughput. Also, on a core like Jaguar that double-pumps 256-bit ops, there's an unseen win because two 128-bit ops have the same cost as the wider 256-bit op. SSE/AVX2/AXV512 are not affected which is expected because only AVX1 has the extract/concat ops to match the pattern. 2. do_not_use_256bit_op() is the best case. Everyone wins by avoiding the concat/extract. Related bug for IR filed as: https://bugs.llvm.org/show_bug.cgi?id=33026 3. The SSE diffs in vector-trunc-math.ll are just scheduling/RA, so nothing real AFAICT. 4. The AVX1 diffs in vector-tzcnt-256.ll are all the same pattern: we reduced the instruction count by one in each case by eliminating two insert/extract while adding one narrower logic op. https://bugs.llvm.org/show_bug.cgi?id=32790 Differential Revision: https://reviews.llvm.org/D33137 llvm-svn: 303997
2017-05-26 23:33:18 +08:00
; AVX1-NEXT: vpaddd %xmm1, %xmm0, %xmm4
; AVX1-NEXT: vextractf128 $1, %ymm1, %xmm1
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm0
; AVX1-NEXT: vpaddd %xmm1, %xmm0, %xmm0
[DAGCombiner] use narrow vector ops to eliminate concat/extract (PR32790) In the best case: extract (binop (concat X1, X2), (concat Y1, Y2)), N --> binop XN, YN ...we kill all of the extract/concat and just have narrow binops remaining. If only one of the binop operands is amenable, this transform is still worthwhile because we kill some of the extract/concat. Optional bitcasting makes the code more complicated, but there doesn't seem to be a way to avoid that. The TODO about extending to more than bitwise logic is there because we really will regress several x86 tests including madd, psad, and even a plain integer-multiply-by-2 or shift-left-by-1. I don't think there's anything fundamentally wrong with this patch that would cause those regressions; those folds are just missing or brittle. If we extend to more binops, I found that this patch will fire on at least one non-x86 regression test. There's an ARM NEON test in test/CodeGen/ARM/coalesce-subregs.ll with a pattern like: t5: v2f32 = vector_shuffle<0,3> t2, t4 t6: v1i64 = bitcast t5 t8: v1i64 = BUILD_VECTOR Constant:i64<0> t9: v2i64 = concat_vectors t6, t8 t10: v4f32 = bitcast t9 t12: v4f32 = fmul t11, t10 t13: v2i64 = bitcast t12 t16: v1i64 = extract_subvector t13, Constant:i32<0> There was no functional change in the codegen from this transform from what I could see though. For the x86 test changes: 1. PR32790() is the closest call. We don't reduce the AVX1 instruction count in that case, but we improve throughput. Also, on a core like Jaguar that double-pumps 256-bit ops, there's an unseen win because two 128-bit ops have the same cost as the wider 256-bit op. SSE/AVX2/AXV512 are not affected which is expected because only AVX1 has the extract/concat ops to match the pattern. 2. do_not_use_256bit_op() is the best case. Everyone wins by avoiding the concat/extract. Related bug for IR filed as: https://bugs.llvm.org/show_bug.cgi?id=33026 3. The SSE diffs in vector-trunc-math.ll are just scheduling/RA, so nothing real AFAICT. 4. The AVX1 diffs in vector-tzcnt-256.ll are all the same pattern: we reduced the instruction count by one in each case by eliminating two insert/extract while adding one narrower logic op. https://bugs.llvm.org/show_bug.cgi?id=32790 Differential Revision: https://reviews.llvm.org/D33137 llvm-svn: 303997
2017-05-26 23:33:18 +08:00
; AVX1-NEXT: vextractf128 $1, %ymm2, %xmm1
; AVX1-NEXT: vpand %xmm1, %xmm0, %xmm0
; AVX1-NEXT: vextractf128 $1, %ymm3, %xmm1
; AVX1-NEXT: vpsubd %xmm1, %xmm0, %xmm0
; AVX1-NEXT: vpand %xmm2, %xmm4, %xmm1
; AVX1-NEXT: vpsubd %xmm3, %xmm1, %xmm1
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
;
; AVX2-LABEL: PR32790:
; AVX2: # BB#0:
; AVX2-NEXT: vpaddd %ymm1, %ymm0, %ymm0
; AVX2-NEXT: vpand %ymm2, %ymm0, %ymm0
; AVX2-NEXT: vpsubd %ymm3, %ymm0, %ymm0
; AVX2-NEXT: retq
;
; AVX512-LABEL: PR32790:
; AVX512: # BB#0:
; AVX512-NEXT: vpaddd %ymm1, %ymm0, %ymm0
; AVX512-NEXT: vpand %ymm2, %ymm0, %ymm0
; AVX512-NEXT: vpsubd %ymm3, %ymm0, %ymm0
; AVX512-NEXT: retq
%add = add <8 x i32> %a, %b
%and = and <8 x i32> %add, %c
%sub = sub <8 x i32> %and, %d
ret <8 x i32> %sub
}
; In a more extreme case, even the later AVX targets should avoid extract/insert just
; because 256-bit ops are supported.
define <4 x i32> @do_not_use_256bit_op(<4 x i32> %a, <4 x i32> %b, <4 x i32> %c, <4 x i32> %d) {
; SSE-LABEL: do_not_use_256bit_op:
; SSE: # BB#0:
; SSE-NEXT: pand %xmm2, %xmm0
[DAGCombiner] use narrow vector ops to eliminate concat/extract (PR32790) In the best case: extract (binop (concat X1, X2), (concat Y1, Y2)), N --> binop XN, YN ...we kill all of the extract/concat and just have narrow binops remaining. If only one of the binop operands is amenable, this transform is still worthwhile because we kill some of the extract/concat. Optional bitcasting makes the code more complicated, but there doesn't seem to be a way to avoid that. The TODO about extending to more than bitwise logic is there because we really will regress several x86 tests including madd, psad, and even a plain integer-multiply-by-2 or shift-left-by-1. I don't think there's anything fundamentally wrong with this patch that would cause those regressions; those folds are just missing or brittle. If we extend to more binops, I found that this patch will fire on at least one non-x86 regression test. There's an ARM NEON test in test/CodeGen/ARM/coalesce-subregs.ll with a pattern like: t5: v2f32 = vector_shuffle<0,3> t2, t4 t6: v1i64 = bitcast t5 t8: v1i64 = BUILD_VECTOR Constant:i64<0> t9: v2i64 = concat_vectors t6, t8 t10: v4f32 = bitcast t9 t12: v4f32 = fmul t11, t10 t13: v2i64 = bitcast t12 t16: v1i64 = extract_subvector t13, Constant:i32<0> There was no functional change in the codegen from this transform from what I could see though. For the x86 test changes: 1. PR32790() is the closest call. We don't reduce the AVX1 instruction count in that case, but we improve throughput. Also, on a core like Jaguar that double-pumps 256-bit ops, there's an unseen win because two 128-bit ops have the same cost as the wider 256-bit op. SSE/AVX2/AXV512 are not affected which is expected because only AVX1 has the extract/concat ops to match the pattern. 2. do_not_use_256bit_op() is the best case. Everyone wins by avoiding the concat/extract. Related bug for IR filed as: https://bugs.llvm.org/show_bug.cgi?id=33026 3. The SSE diffs in vector-trunc-math.ll are just scheduling/RA, so nothing real AFAICT. 4. The AVX1 diffs in vector-tzcnt-256.ll are all the same pattern: we reduced the instruction count by one in each case by eliminating two insert/extract while adding one narrower logic op. https://bugs.llvm.org/show_bug.cgi?id=32790 Differential Revision: https://reviews.llvm.org/D33137 llvm-svn: 303997
2017-05-26 23:33:18 +08:00
; SSE-NEXT: pand %xmm3, %xmm1
; SSE-NEXT: psubd %xmm1, %xmm0
; SSE-NEXT: retq
;
[DAGCombiner] use narrow vector ops to eliminate concat/extract (PR32790) In the best case: extract (binop (concat X1, X2), (concat Y1, Y2)), N --> binop XN, YN ...we kill all of the extract/concat and just have narrow binops remaining. If only one of the binop operands is amenable, this transform is still worthwhile because we kill some of the extract/concat. Optional bitcasting makes the code more complicated, but there doesn't seem to be a way to avoid that. The TODO about extending to more than bitwise logic is there because we really will regress several x86 tests including madd, psad, and even a plain integer-multiply-by-2 or shift-left-by-1. I don't think there's anything fundamentally wrong with this patch that would cause those regressions; those folds are just missing or brittle. If we extend to more binops, I found that this patch will fire on at least one non-x86 regression test. There's an ARM NEON test in test/CodeGen/ARM/coalesce-subregs.ll with a pattern like: t5: v2f32 = vector_shuffle<0,3> t2, t4 t6: v1i64 = bitcast t5 t8: v1i64 = BUILD_VECTOR Constant:i64<0> t9: v2i64 = concat_vectors t6, t8 t10: v4f32 = bitcast t9 t12: v4f32 = fmul t11, t10 t13: v2i64 = bitcast t12 t16: v1i64 = extract_subvector t13, Constant:i32<0> There was no functional change in the codegen from this transform from what I could see though. For the x86 test changes: 1. PR32790() is the closest call. We don't reduce the AVX1 instruction count in that case, but we improve throughput. Also, on a core like Jaguar that double-pumps 256-bit ops, there's an unseen win because two 128-bit ops have the same cost as the wider 256-bit op. SSE/AVX2/AXV512 are not affected which is expected because only AVX1 has the extract/concat ops to match the pattern. 2. do_not_use_256bit_op() is the best case. Everyone wins by avoiding the concat/extract. Related bug for IR filed as: https://bugs.llvm.org/show_bug.cgi?id=33026 3. The SSE diffs in vector-trunc-math.ll are just scheduling/RA, so nothing real AFAICT. 4. The AVX1 diffs in vector-tzcnt-256.ll are all the same pattern: we reduced the instruction count by one in each case by eliminating two insert/extract while adding one narrower logic op. https://bugs.llvm.org/show_bug.cgi?id=32790 Differential Revision: https://reviews.llvm.org/D33137 llvm-svn: 303997
2017-05-26 23:33:18 +08:00
; AVX-LABEL: do_not_use_256bit_op:
; AVX: # BB#0:
; AVX-NEXT: vpand %xmm2, %xmm0, %xmm0
; AVX-NEXT: vpand %xmm3, %xmm1, %xmm1
; AVX-NEXT: vpsubd %xmm1, %xmm0, %xmm0
; AVX-NEXT: retq
%concat1 = shufflevector <4 x i32> %a, <4 x i32> %b, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%concat2 = shufflevector <4 x i32> %c, <4 x i32> %d, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%and = and <8 x i32> %concat1, %concat2
%extract1 = shufflevector <8 x i32> %and, <8 x i32> undef, <4 x i32> <i32 0, i32 1, i32 2, i32 3>
%extract2 = shufflevector <8 x i32> %and, <8 x i32> undef, <4 x i32> <i32 4, i32 5, i32 6, i32 7>
%sub = sub <4 x i32> %extract1, %extract2
ret <4 x i32> %sub
}