[x86] Begin stubbing out the AVX support in the new vector shuffle

lowering scheme.

Currently, this just directly bails to the fallback path of splitting
the 256-bit vector into two 128-bit vectors, operating there, and then
joining the results back together. While the results are far from
perfect, they are *shockingly* good for what we're doing here. I'll be
layering the rest of the functionality on top of this piece by piece and
updating tests as I go.

Note that 256-bit vectors in this mode are still somewhat WIP. While
I think the code paths that I'm adding here are clean and good-to-go,
there are still a lot of 128-bit assumptions that I'll need to stomp out
as I march through the functional spread here.

llvm-svn: 215637
This commit is contained in:
Chandler Carruth 2014-08-14 12:13:59 +00:00
parent 73ff948746
commit a8311b3681
2 changed files with 346 additions and 0 deletions

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@ -8334,6 +8334,91 @@ static SDValue lower128BitVectorShuffle(SDValue Op, SDValue V1, SDValue V2,
}
}
/// \brief Generic routine to split a 256-bit vector shuffle into 128-bit
/// shuffles.
///
/// There is a severely limited set of shuffles available in AVX1 for 256-bit
/// vectors resulting in routinely needing to split the shuffle into two 128-bit
/// shuffles. This can be done generically for any 256-bit vector shuffle and so
/// we encode the logic here for specific shuffle lowering routines to bail to
/// when they exhaust the features avaible to more directly handle the shuffle.
static SDValue splitAndLower256BitVectorShuffle(SDValue Op, SDValue V1,
SDValue V2,
const X86Subtarget *Subtarget,
SelectionDAG &DAG) {
SDLoc DL(Op);
MVT VT = Op.getSimpleValueType();
assert(VT.getSizeInBits() == 256 && "Only for 256-bit vector shuffles!");
assert(V1.getSimpleValueType() == VT && "Bad operand type!");
assert(V2.getSimpleValueType() == VT && "Bad operand type!");
ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(Op);
ArrayRef<int> Mask = SVOp->getMask();
ArrayRef<int> LoMask = Mask.slice(0, Mask.size()/2);
ArrayRef<int> HiMask = Mask.slice(Mask.size()/2);
int NumElements = VT.getVectorNumElements();
int SplitNumElements = NumElements / 2;
MVT ScalarVT = VT.getScalarType();
MVT SplitVT = MVT::getVectorVT(ScalarVT, NumElements / 2);
SDValue LoV1 = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, SplitVT, V1,
DAG.getIntPtrConstant(0));
SDValue HiV1 = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, SplitVT, V1,
DAG.getIntPtrConstant(SplitNumElements));
SDValue LoV2 = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, SplitVT, V2,
DAG.getIntPtrConstant(0));
SDValue HiV2 = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, SplitVT, V2,
DAG.getIntPtrConstant(SplitNumElements));
// Now create two 4-way blends of these half-width vectors.
auto HalfBlend = [&](ArrayRef<int> HalfMask) {
SmallVector<int, 16> V1BlendMask, V2BlendMask, BlendMask;
for (int i = 0; i < SplitNumElements; ++i) {
int M = HalfMask[i];
if (M >= NumElements) {
V2BlendMask.push_back(M - NumElements);
V1BlendMask.push_back(-1);
BlendMask.push_back(SplitNumElements + i);
} else if (M >= 0) {
V2BlendMask.push_back(-1);
V1BlendMask.push_back(M);
BlendMask.push_back(i);
} else {
V2BlendMask.push_back(-1);
V1BlendMask.push_back(-1);
BlendMask.push_back(-1);
}
}
SDValue V1Blend = DAG.getVectorShuffle(SplitVT, DL, LoV1, HiV1, V1BlendMask);
SDValue V2Blend = DAG.getVectorShuffle(SplitVT, DL, LoV2, HiV2, V2BlendMask);
return DAG.getVectorShuffle(SplitVT, DL, V1Blend, V2Blend, BlendMask);
};
SDValue Lo = HalfBlend(LoMask);
SDValue Hi = HalfBlend(HiMask);
return DAG.getNode(ISD::CONCAT_VECTORS, DL, VT, Lo, Hi);
}
/// \brief High-level routine to lower various 256-bit x86 vector shuffles.
///
/// This routine either breaks down the specific type of a 256-bit x86 vector
/// shuffle or splits it into two 128-bit shuffles and fuses the results back
/// together based on the available instructions.
static SDValue lower256BitVectorShuffle(SDValue Op, SDValue V1, SDValue V2,
MVT VT, const X86Subtarget *Subtarget,
SelectionDAG &DAG) {
// FIXME: We should detect symmetric patterns and re-use the 128-bit shuffle
// lowering logic with wider types in that case.
// FIXME: We should detect when we can use AVX2 cross-half shuffles to either
// implement the shuffle completely, more effectively build symmetry, or
// minimize half-blends.
// Fall back to the basic pattern of extracting the high half and forming
// a 4-way blend.
return splitAndLower256BitVectorShuffle(Op, V1, V2, Subtarget, DAG);
}
/// \brief Tiny helper function to test whether a shuffle mask could be
/// simplified by widening the elements being shuffled.
static bool canWidenShuffleElements(ArrayRef<int> Mask) {
@ -8437,6 +8522,9 @@ static SDValue lowerVectorShuffle(SDValue Op, const X86Subtarget *Subtarget,
if (VT.getSizeInBits() == 128)
return lower128BitVectorShuffle(Op, V1, V2, VT, Subtarget, DAG);
if (VT.getSizeInBits() == 256)
return lower256BitVectorShuffle(Op, V1, V2, VT, Subtarget, DAG);
llvm_unreachable("Unimplemented!");
}

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@ -0,0 +1,258 @@
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=x86-64 -mattr=+avx -x86-experimental-vector-shuffle-lowering | FileCheck %s --check-prefix=AVX1
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-unknown"
define <4 x i64> @shuffle_v4i64_0001(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0001
; AVX1: # BB#0:
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm0[0,1,0,1]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 0, i32 0, i32 1>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0020(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0020
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm1[0],xmm0[0]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[0,1,0,1]
; AVX1-NEXT: vinsertf128 $1, %xmm1, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 0, i32 2, i32 0>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0112(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0112
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm0[1],xmm1[0]
; AVX1-NEXT: vinsertf128 $1, %xmm1, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 1, i32 1, i32 2>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0300(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0300
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm0[0],xmm1[1]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[0,1,0,1]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 3, i32 0, i32 0>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_1000(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_1000
; AVX1: # BB#0:
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm0[2,3,0,1]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[0,1,0,1]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 1, i32 0, i32 0, i32 0>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_2200(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_2200
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm1[0,1,0,1]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[0,1,0,1]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 2, i32 2, i32 0, i32 0>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_3330(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_3330
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm1[1],xmm0[0]
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm1[2,3,2,3]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 3, i32 3, i32 3, i32 0>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_3210(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_3210
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm1[2,3,0,1]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[2,3,0,1]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
ret <4 x i64> %shuffle
}
define <4 x double> @shuffle_v4f64_0001(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_0001
; AVX1: # BB#0:
; AVX1-NEXT: vmovlhps {{.*}} # xmm1 = xmm0[0,0]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 0, i32 0, i32 0, i32 1>
ret <4 x double> %shuffle
}
define <4 x double> @shuffle_v4f64_0020(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_0020
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm1[0],xmm0[0]
; AVX1-NEXT: vmovlhps {{.*}} # xmm0 = xmm0[0,0]
; AVX1-NEXT: vinsertf128 $1, %xmm1, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 0, i32 0, i32 2, i32 0>
ret <4 x double> %shuffle
}
define <4 x double> @shuffle_v4f64_0300(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_0300
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm0[0],xmm1[1]
; AVX1-NEXT: vmovlhps {{.*}} # xmm0 = xmm0[0,0]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 0, i32 3, i32 0, i32 0>
ret <4 x double> %shuffle
}
define <4 x double> @shuffle_v4f64_1000(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_1000
; AVX1: # BB#0:
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm0[1,0]
; AVX1-NEXT: vmovlhps {{.*}} # xmm0 = xmm0[0,0]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 1, i32 0, i32 0, i32 0>
ret <4 x double> %shuffle
}
define <4 x double> @shuffle_v4f64_2200(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_2200
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vmovlhps {{.*}} # xmm1 = xmm1[0,0]
; AVX1-NEXT: vmovlhps {{.*}} # xmm0 = xmm0[0,0]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 2, i32 2, i32 0, i32 0>
ret <4 x double> %shuffle
}
define <4 x double> @shuffle_v4f64_3330(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_3330
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm1[1],xmm0[0]
; AVX1-NEXT: vmovhlps {{.*}} # xmm1 = xmm1[1,1]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 3, i32 3, i32 3, i32 0>
ret <4 x double> %shuffle
}
define <4 x double> @shuffle_v4f64_3210(<4 x double> %a, <4 x double> %b) {
; AVX1-LABEL: @shuffle_v4f64_3210
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm1
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm1[1,0]
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm0[1,0]
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x double> %a, <4 x double> %b, <4 x i32> <i32 3, i32 2, i32 1, i32 0>
ret <4 x double> %shuffle
}
define <4 x i64> @shuffle_v4i64_0124(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0124
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm2
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm1[0,1,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm2[0],xmm1[1]
; AVX1-NEXT: vinsertf128 $1, %xmm1, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 1, i32 2, i32 4>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0142(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0142
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm2
; AVX1-NEXT: vpshufd {{.*}} # xmm2 = xmm2[0,1,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm1 = xmm1[0],xmm2[1]
; AVX1-NEXT: vinsertf128 $1, %xmm1, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 1, i32 4, i32 2>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0412(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0412
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm2
; AVX1-NEXT: vshufpd {{.*}} # xmm2 = xmm0[1],xmm2[0]
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm1[0,1,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm0[0],xmm1[1]
; AVX1-NEXT: vinsertf128 $1, %xmm2, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 4, i32 1, i32 2>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_4012(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_4012
; AVX1: # BB#0:
; AVX1-NEXT: vextractf128 $1, %ymm0, %xmm2
; AVX1-NEXT: vshufpd {{.*}} # xmm2 = xmm0[1],xmm2[0]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[0,1,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm1[0],xmm0[1]
; AVX1-NEXT: vinsertf128 $1, %xmm2, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 4, i32 0, i32 1, i32 2>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0145(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0145
; AVX1: # BB#0:
; AVX1-NEXT: vinsertf128 $1, %xmm1, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 1, i32 4, i32 5>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_0451(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_0451
; AVX1: # BB#0:
; AVX1-NEXT: vpshufd {{.*}} # xmm2 = xmm1[2,3,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm2 = xmm2[0],xmm0[1]
; AVX1-NEXT: vpshufd {{.*}} # xmm1 = xmm1[0,1,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm0[0],xmm1[1]
; AVX1-NEXT: vinsertf128 $1, %xmm2, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 0, i32 4, i32 5, i32 1>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_4501(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_4501
; AVX1: # BB#0:
; AVX1-NEXT: vinsertf128 $1, %xmm0, %ymm1, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 4, i32 5, i32 0, i32 1>
ret <4 x i64> %shuffle
}
define <4 x i64> @shuffle_v4i64_4015(<4 x i64> %a, <4 x i64> %b) {
; AVX1-LABEL: @shuffle_v4i64_4015
; AVX1: # BB#0:
; AVX1-NEXT: vpshufd {{.*}} # xmm2 = xmm0[2,3,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm2 = xmm2[0],xmm1[1]
; AVX1-NEXT: vpshufd {{.*}} # xmm0 = xmm0[0,1,0,1]
; AVX1-NEXT: vshufpd {{.*}} # xmm0 = xmm1[0],xmm0[1]
; AVX1-NEXT: vinsertf128 $1, %xmm2, %ymm0, %ymm0
; AVX1-NEXT: retq
%shuffle = shufflevector <4 x i64> %a, <4 x i64> %b, <4 x i32> <i32 4, i32 0, i32 1, i32 5>
ret <4 x i64> %shuffle
}