[AArch64] Add custom store lowering for 256 bit non-temporal stores.

[fhahn]

Summary

Currently we fail to lower non-termporal stores for 256+ bit vectors
to STNPQ, because type legalization will split them up to 128 bit stores
and because there are no single non-temporal stores, creating STPNQ
in the Load/Store optimizer would be quite tricky.

This patch adds custom lowering for 256 bit non-temporal vector stores
to improve the generated code.

[merge_guards_bot]

Unit tests: pass. 61937 tests passed, 0 failed and 783 were skipped.

clang-tidy: unknown.

clang-format: fail. Please format your changes with clang-format by running git-clang-format HEAD^ or applying this patch.

Build artifacts: diff.json, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

[dmgreen]

llvm/lib/Target/AArch64/AArch64InstrInfo.td

2727

Should this be simm7s16? Same for am_indexed7s128

llvm/test/CodeGen/AArch64/nontemporal.ll

361

Should halves work too?

372

Nit: There's an extra " " here it seems

[fhahn]

Thanks for taking a look @dmgreen. I've fixed the offset arguments and added the missing v16f16 handler.

[fhahn]

llvm/lib/Target/AArch64/AArch64InstrInfo.td

2727

Yes! I've updated that and now the offsets should be correct.

llvm/test/CodeGen/AArch64/nontemporal.ll

361

Yes, I've added the missing handler for v16f16.

[merge_guards_bot]

Unit tests: pass. 62002 tests passed, 0 failed and 783 were skipped.

clang-tidy: unknown.

clang-format: fail. Please format your changes with clang-format by running git-clang-format HEAD^ or applying this patch.

Build artifacts: diff.json, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

[dmgreen]

LGTM. Thanks

[fhahn]

Thanks Dave!

llvm/lib/Target/AArch64/AArch64ISelLowering.h

enum NodeType : unsigned {
   /// need to re-interpret the data in SIMD vector registers in big-endian
   /// mode without emitting such REV instructions.
   NVCAST,
 
   SMULL,
   UMULL,
 
   // Reciprocal estimates and steps.
   FRECPE, FRECPS,
   FRSQRTE, FRSQRTS,
 
   SUNPKHI,
   SUNPKLO,
   UUNPKHI,
   UUNPKLO,
 
   CLASTA_N,
enum NodeType : unsigned {
   ST4LANEpost,
 
   STG,
   STZG,
   ST2G,
   STZ2G,
 
   LDP,
-  STP
+  STP,
+  STNP
 };
 
 } // end namespace AArch64ISD
 
 namespace {
 
 // Any instruction that defines a 32-bit result zeros out the high half of the
 // register. Truncate can be lowered to EXTRACT_SUBREG. CopyFromReg may

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

AArch64TargetLowering::AArch64TargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::ATOMIC_LOAD_SUB, MVT::i64, Custom);
   setOperationAction(ISD::ATOMIC_LOAD_AND, MVT::i32, Custom);
   setOperationAction(ISD::ATOMIC_LOAD_AND, MVT::i64, Custom);
 
   // 128-bit loads and stores can be done without expanding
   setOperationAction(ISD::LOAD, MVT::i128, Custom);
   setOperationAction(ISD::STORE, MVT::i128, Custom);
 
+  // 256 bit non-temporal stores can be lowered to STNP. Do this as part of the
+  // custom lowering, as there are no un-paired non-temporal stores and
+  // legalization will break up 256 bit inputs.
+  setOperationAction(ISD::STORE, MVT::v32i8, Custom);
+  setOperationAction(ISD::STORE, MVT::v16i16, Custom);
+  setOperationAction(ISD::STORE, MVT::v8i32, Custom);
+  setOperationAction(ISD::STORE, MVT::v8f32, Custom);
+  setOperationAction(ISD::STORE, MVT::v4f64, Custom);
+  setOperationAction(ISD::STORE, MVT::v4i64, Custom);
+
   // Lower READCYCLECOUNTER using an mrs from PMCCNTR_EL0.
   // This requires the Performance Monitors extension.
   if (Subtarget->hasPerfMon())
     setOperationAction(ISD::READCYCLECOUNTER, MVT::i64, Legal);
 
   if (getLibcallName(RTLIB::SINCOS_STRET_F32) != nullptr &&
       getLibcallName(RTLIB::SINCOS_STRET_F64) != nullptr) {
     // Issue __sincos_stret if available.
const char *AArch64TargetLowering::getTargetNodeName(unsigned Opcode) const {
   case AArch64ISD::SST1_SCALED:       return "AArch64ISD::SST1_SCALED";
   case AArch64ISD::SST1_SXTW:         return "AArch64ISD::SST1_SXTW";
   case AArch64ISD::SST1_UXTW:         return "AArch64ISD::SST1_UXTW";
   case AArch64ISD::SST1_SXTW_SCALED:  return "AArch64ISD::SST1_SXTW_SCALED";
   case AArch64ISD::SST1_UXTW_SCALED:  return "AArch64ISD::SST1_UXTW_SCALED";
   case AArch64ISD::SST1_IMM:          return "AArch64ISD::SST1_IMM";
   case AArch64ISD::LDP:               return "AArch64ISD::LDP";
   case AArch64ISD::STP:               return "AArch64ISD::STP";
+  case AArch64ISD::STNP:              return "AArch64ISD::STNP";
   }
   return nullptr;
 }
 
 MachineBasicBlock *
 AArch64TargetLowering::EmitF128CSEL(MachineInstr &MI,
                                     MachineBasicBlock *MBB) const {
   // We materialise the F128CSEL pseudo-instruction as some control flow and a
if (Align < MemVT.getStoreSize() &&
                                         StoreNode->getMemOperand()->getFlags(),
                                         nullptr)) {
       return scalarizeVectorStore(StoreNode, DAG);
     }
 
     if (StoreNode->isTruncatingStore()) {
       return LowerTruncateVectorStore(Dl, StoreNode, VT, MemVT, DAG);
     }
+    // 256 bit non-temporal stores can be lowered to STNP. Do this as part of
+    // the custom lowering, as there are no un-paired non-temporal stores and
+    // legalization will break up 256 bit inputs.
+    if (StoreNode->isNonTemporal() && MemVT.getSizeInBits() == 256u &&
+        MemVT.getVectorElementCount().Min % 2u == 0 &&
+        ((MemVT.getScalarSizeInBits() == 8u ||
+          MemVT.getScalarSizeInBits() == 16u ||
+          MemVT.getScalarSizeInBits() == 32u ||
+          MemVT.getScalarSizeInBits() == 64u))) {
+      SDValue Lo =
+          DAG.getNode(ISD::EXTRACT_SUBVECTOR, Dl,
+                      MemVT.getHalfNumVectorElementsVT(*DAG.getContext()),
+                      StoreNode->getValue(), DAG.getConstant(0, Dl, MVT::i64));
+      SDValue Hi = DAG.getNode(
+          ISD::EXTRACT_SUBVECTOR, Dl,
+          MemVT.getHalfNumVectorElementsVT(*DAG.getContext()),
+          StoreNode->getValue(),
+          DAG.getConstant(MemVT.getVectorElementCount().Min / 2, Dl, MVT::i64));
+      SDValue Result = DAG.getMemIntrinsicNode(
+          AArch64ISD::STNP, Dl, DAG.getVTList(MVT::Other),
+          {StoreNode->getChain(), Lo, Hi, StoreNode->getBasePtr()},
+          StoreNode->getMemoryVT(), StoreNode->getMemOperand());
+      return Result;
+    }
   } else if (MemVT == MVT::i128 && StoreNode->isVolatile()) {
     assert(StoreNode->getValue()->getValueType(0) == MVT::i128);
     SDValue Lo =
         DAG.getNode(ISD::EXTRACT_ELEMENT, Dl, MVT::i64, StoreNode->getValue(),
                     DAG.getConstant(0, Dl, MVT::i64));
     SDValue Hi =
         DAG.getNode(ISD::EXTRACT_ELEMENT, Dl, MVT::i64, StoreNode->getValue(),
                     DAG.getConstant(1, Dl, MVT::i64));

llvm/lib/Target/AArch64/AArch64InstrInfo.td

 
 def SDT_AArch64ITOF  : SDTypeProfile<1, 1, [SDTCisFP<0>, SDTCisSameAs<0,1>]>;
 
 def SDT_AArch64TLSDescCall : SDTypeProfile<0, -2, [SDTCisPtrTy<0>,
                                                  SDTCisPtrTy<1>]>;
 
 def SDT_AArch64ldp : SDTypeProfile<2, 1, [SDTCisVT<0, i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
 def SDT_AArch64stp : SDTypeProfile<0, 3, [SDTCisVT<0, i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
+def SDT_AArch64stnp : SDTypeProfile<0, 3, [SDTCisVT<0, v4i32>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
 
 // Generates the general dynamic sequences, i.e.
 //  adrp  x0, :tlsdesc:var
 //  ldr   x1, [x0, #:tlsdesc_lo12:var]
 //  add   x0, x0, #:tlsdesc_lo12:var
 //  .tlsdesccall var
 //  blr   x1
 

 ]>;
 def AArch64sunpkhi : SDNode<"AArch64ISD::SUNPKHI", SDT_AArch64unpk>;
 def AArch64sunpklo : SDNode<"AArch64ISD::SUNPKLO", SDT_AArch64unpk>;
 def AArch64uunpkhi : SDNode<"AArch64ISD::UUNPKHI", SDT_AArch64unpk>;
 def AArch64uunpklo : SDNode<"AArch64ISD::UUNPKLO", SDT_AArch64unpk>;
 
 def AArch64ldp : SDNode<"AArch64ISD::LDP", SDT_AArch64ldp, [SDNPHasChain, SDNPMayLoad, SDNPMemOperand]>;
 def AArch64stp : SDNode<"AArch64ISD::STP", SDT_AArch64stp, [SDNPHasChain, SDNPMayStore, SDNPMemOperand]>;
+def AArch64stnp : SDNode<"AArch64ISD::STNP", SDT_AArch64stnp, [SDNPHasChain, SDNPMayStore, SDNPMemOperand]>;
 
 def AArch64tbl : SDNode<"AArch64ISD::TBL", SDT_AArch64TBL>;
 
 //===----------------------------------------------------------------------===//
 
 //===----------------------------------------------------------------------===//
 
 // AArch64 Instruction Predicate Definitions.

 defm STNPX : StorePairNoAlloc<0b10, 0, GPR64z, simm7s8, "stnp">;
 defm STNPS : StorePairNoAlloc<0b00, 1, FPR32Op, simm7s4, "stnp">;
 defm STNPD : StorePairNoAlloc<0b01, 1, FPR64Op, simm7s8, "stnp">;
 defm STNPQ : StorePairNoAlloc<0b10, 1, FPR128Op, simm7s16, "stnp">;
 
 def : Pat<(AArch64stp GPR64z:$Rt, GPR64z:$Rt2, (am_indexed7s64 GPR64sp:$Rn, simm7s8:$offset)),
           (STPXi GPR64z:$Rt, GPR64z:$Rt2, GPR64sp:$Rn, simm7s8:$offset)>;
 
+def : Pat<(AArch64stnp FPR128:$Rt, FPR128:$Rt2, (am_indexed7s64 GPR64sp:$Rn, simm7s8:$offset)),
+          (STNPQi FPR128:$Rt, FPR128:$Rt2, GPR64sp:$Rn, simm7s8:$offset)>;
+
+
 //---
 // (Register offset)
 
 // Integer
 defm STRBB : Store8RO< 0b00, 0, 0b00, GPR32, "strb", i32, truncstorei8>;
 defm STRHH : Store16RO<0b01, 0, 0b00, GPR32, "strh", i32, truncstorei16>;
 defm STRW  : Store32RO<0b10, 0, 0b00, GPR32, "str",  i32, store>;
 defm STRX  : Store64RO<0b11, 0, 0b00, GPR64, "str",  i64, store>;

llvm/test/CodeGen/AArch64/nontemporal.ll

 ; RUN: llc < %s -mtriple aarch64-apple-darwin -asm-verbose=false -disable-post-ra | FileCheck %s
 
 define void @test_stnp_v4i64(<4 x i64>* %p, <4 x i64> %v) #0 {
 ; CHECK-LABEL: test_stnp_v4i64:
-; CHECK-NEXT:  mov d[[HI1:[0-9]+]], v1[1]
-; CHECK-NEXT:  mov d[[HI0:[0-9]+]], v0[1]
-; CHECK-NEXT:  stnp d1, d[[HI1]], [x0, #16]
-; CHECK-NEXT:  stnp d0, d[[HI0]], [x0]
+; CHECK-NEXT:  stnp q0, q1, [x0]
 ; CHECK-NEXT:  ret
   store <4 x i64> %v, <4 x i64>* %p, align 1, !nontemporal !0
   ret void
 }
 
 define void @test_stnp_v4i32(<4 x i32>* %p, <4 x i32> %v) #0 {
 ; CHECK-LABEL: test_stnp_v4i32:
 ; CHECK-NEXT:  mov d[[HI:[0-9]+]], v0[1]

 ; CHECK-NEXT:  bl _dummy
   %tmp0 = alloca <4 x float>, i32 2
   %tmp1 = getelementptr <4 x float>, <4 x float>* %tmp0, i32 1
   store <4 x float> %v, <4 x float>* %tmp1, align 1, !nontemporal !0
   call void @dummy(<4 x float>* %tmp0)
   ret void
 }
 
+define void @test_stnp_v32i8(<32 x i8> %v, <32 x i8>* %ptr) {
+; CHECK-LABEL: _test_stnp_v32i8:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:    stnp    q0, q1, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <32 x i8> %v, <32 x i8>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v16i16(<16 x i16> %v, <16 x i16>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16i16:
+; CHECK:         stnp    q0, q1, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <16 x i16> %v, <16 x i16>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v16f16(<16 x half> %v, <16 x half>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16f16:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:    mov d2, v1[1]
+; CHECK-NEXT:    mov d3, v0[1]
+; CHECK-NEXT:    stnp    d1, d2, [x0, #16]
+; CHECK-NEXT:    stnp    d0, d3, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <16 x half> %v, <16 x half>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v16i32(<16 x i32> %v, <16 x i32>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16i32:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:     stnp    q2, q3, [x0, #64]
+; CHECK-NEXT:    stnp    q0, q1, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <16 x i32> %v, <16 x i32>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v16f32(<16 x float> %v, <16 x float>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16f32:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:    stnp    q2, q3, [x0, #64]
+; CHECK-NEXT:    stnp    q0, q1, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <16 x float> %v, <16 x float>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v17f32(<17 x float> %v, <17 x float>* %ptr) {
+; CHECK-LABEL: _test_stnp_v17f32:
+; CHECK-NEXT: .cfi_startproc
+; CHECK-NEXT: ldr s16, [sp, #16]
+; CHECK-NEXT: mov.s v0[1], v1[0]
+; CHECK-NEXT: mov.s v4[1], v5[0]
+; CHECK-NEXT: ldr s1, [sp]
+; CHECK-NEXT: add x8, sp, #20
+; CHECK-NEXT: ld1.s { v16 }[1], [x8]
+; CHECK-NEXT: add x8, sp, #4
+; CHECK-NEXT: ld1.s { v1 }[1], [x8]
+; CHECK-NEXT: add x8, sp, #24
+; CHECK-NEXT: ld1.s { v16 }[2], [x8]
+; CHECK-NEXT: add x8, sp, #8
+; CHECK-NEXT: ld1.s { v1 }[2], [x8]
+; CHECK-NEXT: add x8, sp, #28
+; CHECK-NEXT: ld1.s { v16 }[3], [x8]
+; CHECK-NEXT: add x8, sp, #12
+; CHECK-NEXT: mov.s v0[2], v2[0]
+; CHECK-NEXT: ldr s2, [sp, #32]
+; CHECK-NEXT: mov.s v4[2], v6[0]
+; CHECK-NEXT: mov.s v0[3], v3[0]
+; CHECK-NEXT: mov.s v4[3], v7[0]
+; CHECK-NEXT: mov d3, v4[1]
+; CHECK-NEXT: mov d5, v0[1]
+; CHECK-NEXT: ld1.s { v1 }[3], [x8]
+; CHECK-NEXT: stnp  d4, d3, [x0, #16]
+; CHECK-NEXT: stnp  d0, d5, [x0]
+; CHECK-NEXT: mov d0, v16[1]
+; CHECK-NEXT: mov d3, v1[1]
+; CHECK-NEXT: stnp  d16, d0, [x0, #48]
+; CHECK-NEXT: stnp  d1, d3, [x0, #32]
+; CHECK-NEXT: str s2, [x0, #64]
+; CHECK-NEXT: ret
+
+entry:
+  store <17 x float> %v, <17 x float>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+define void @test_stnp_v16i32_invalid_offset(<16 x i32> %v, <16 x i32>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16i32_invalid_offset:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:    mov w8, #32000
+; CHECK-NEXT:    mov w9, #32032
+; CHECK-NEXT:    add x8, x0, x8
+; CHECK-NEXT:    add x9, x0, x9
+; CHECK-NEXT:    stnp    q2, q3, [x9]
+; CHECK-NEXT:    stnp    q0, q1, [x8]
+; CHECK-NEXT:    ret
+
+entry:
+  %gep = getelementptr <16 x i32>, <16 x i32>* %ptr, i32 500
+  store <16 x i32> %v, <16 x i32>* %gep, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v16f64(<16 x double> %v, <16 x double>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16f64:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:    stnp    q6, q7, [x0, #192]
+; CHECK-NEXT:    stnp    q4, q5, [x0, #128]
+; CHECK-NEXT:    stnp    q2, q3, [x0, #64]
+; CHECK-NEXT:    stnp    q0, q1, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <16 x double> %v, <16 x double>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
+define void @test_stnp_v16i64(<16 x i64> %v, <16 x i64>* %ptr) {
+; CHECK-LABEL: _test_stnp_v16i64:
+; CHECK-NEXT:    .cfi_startproc
+; CHECK-NEXT:    stnp    q6, q7, [x0, #192]
+; CHECK-NEXT:    stnp    q4, q5, [x0, #128]
+; CHECK-NEXT:    stnp    q2, q3, [x0, #64]
+; CHECK-NEXT:    stnp    q0, q1, [x0]
+; CHECK-NEXT:    ret
+
+entry:
+  store <16 x i64> %v, <16 x i64>* %ptr, align 4, !nontemporal !0
+  ret void
+}
+
 !0 = !{ i32 1 }
 
 attributes #0 = { nounwind }