[AMDGPU] Add target intrinsic for s_buffer_prefetch_data

clang/include/clang/Basic/BuiltinsAMDGPU.def

@@ -449,6 +449,7 @@ TARGET_BUILTIN(__builtin_amdgcn_s_wakeup_barrier, "vi", "n", "gfx12-insts")
 TARGET_BUILTIN(__builtin_amdgcn_s_barrier_leave, "b", "n", "gfx12-insts")
 TARGET_BUILTIN(__builtin_amdgcn_s_get_barrier_state, "Uii", "n", "gfx12-insts")
 TARGET_BUILTIN(__builtin_amdgcn_s_prefetch_data, "vvC*Ui", "nc", "gfx12-insts")
+TARGET_BUILTIN(__builtin_amdgcn_s_buffer_prefetch_data, "vQbIiUi", "nc", "gfx12-insts")
 
 TARGET_BUILTIN(__builtin_amdgcn_global_load_tr_b64_v2i32, "V2iV2i*1", "nc", "gfx12-insts,wavefrontsize32")
 TARGET_BUILTIN(__builtin_amdgcn_global_load_tr_b128_v8i16, "V8sV8s*1", "nc", "gfx12-insts,wavefrontsize32")

clang/test/CodeGenOpenCL/builtins-amdgcn-gfx12-param-err.cl

@@ -22,3 +22,8 @@ kernel void builtins_amdgcn_s_barrier_signal_isfirst_err(global int* in, global
   __builtin_amdgcn_s_barrier_wait(-1);
   *out = *in;
 }
+
+void test_s_buffer_prefetch_data(__amdgpu_buffer_rsrc_t rsrc, unsigned int off)
+{
+  __builtin_amdgcn_s_buffer_prefetch_data(rsrc, off, 31); // expected-error {{'__builtin_amdgcn_s_buffer_prefetch_data' must be a constant integer}}
+}

clang/test/CodeGenOpenCL/builtins-amdgcn-gfx12.cl

@@ -281,3 +281,22 @@ void test_s_prefetch_data(int *fp, global float *gp, constant char *cp, unsigned
   __builtin_amdgcn_s_prefetch_data(gp, len);
   __builtin_amdgcn_s_prefetch_data(cp, 31);
 }
+
+// CHECK-LABEL: @test_s_buffer_prefetch_data(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[RSRC_ADDR:%.*]] = alloca ptr addrspace(8), align 16, addrspace(5)
+// CHECK-NEXT:    [[LEN_ADDR:%.*]] = alloca i32, align 4, addrspace(5)
+// CHECK-NEXT:    store ptr addrspace(8) [[RSRC:%.*]], ptr addrspace(5) [[RSRC_ADDR]], align 16
+// CHECK-NEXT:    store i32 [[LEN:%.*]], ptr addrspace(5) [[LEN_ADDR]], align 4
+// CHECK-NEXT:    [[TMP0:%.*]] = load ptr addrspace(8), ptr addrspace(5) [[RSRC_ADDR]], align 16
+// CHECK-NEXT:    [[TMP1:%.*]] = load i32, ptr addrspace(5) [[LEN_ADDR]], align 4
+// CHECK-NEXT:    call void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) [[TMP0]], i32 128, i32 [[TMP1]])
+// CHECK-NEXT:    [[TMP2:%.*]] = load ptr addrspace(8), ptr addrspace(5) [[RSRC_ADDR]], align 16
+// CHECK-NEXT:    call void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) [[TMP2]], i32 0, i32 31)
+// CHECK-NEXT:    ret void
+//
+void test_s_buffer_prefetch_data(__amdgpu_buffer_rsrc_t rsrc, unsigned int len)
+{
+  __builtin_amdgcn_s_buffer_prefetch_data(rsrc, 128, len);
+  __builtin_amdgcn_s_buffer_prefetch_data(rsrc, 0, 31);
+}

llvm/include/llvm/IR/IntrinsicsAMDGPU.td

@@ -1723,6 +1723,15 @@ class AMDGPUStructPtrBufferLoadLDS : Intrinsic <
    ImmArg<ArgIndex<7>>, IntrNoCallback, IntrNoFree], "", [SDNPMemOperand]>, AMDGPURsrcIntrinsic<0>;
 def int_amdgcn_struct_ptr_buffer_load_lds : AMDGPUStructPtrBufferLoadLDS;
 
+def int_amdgcn_s_buffer_prefetch_data : DefaultAttrsIntrinsic <
+  [],
+  [AMDGPUBufferRsrcTy, // rsrc(SGPR)
+   llvm_i32_ty,        // offset (imm)
+   llvm_i32_ty],       // len (SGPR/imm)
+  [IntrInaccessibleMemOrArgMemOnly, ImmArg<ArgIndex<1>>], "", [SDNPMemOperand]>,
+  AMDGPURsrcIntrinsic<0>,
+  ClangBuiltin<"__builtin_amdgcn_s_buffer_prefetch_data">;
+
 } // defset AMDGPUBufferIntrinsics
 
 // Uses that do not set the done bit should set IntrWriteMem on the

llvm/lib/Target/AMDGPU/AMDGPUGISel.td

@@ -296,6 +296,7 @@ def : GINodeEquiv<G_AMDGPU_S_BUFFER_LOAD_SBYTE, SIsbuffer_load_byte>;
 def : GINodeEquiv<G_AMDGPU_S_BUFFER_LOAD_UBYTE, SIsbuffer_load_ubyte>;
 def : GINodeEquiv<G_AMDGPU_S_BUFFER_LOAD_SSHORT, SIsbuffer_load_short>;
 def : GINodeEquiv<G_AMDGPU_S_BUFFER_LOAD_USHORT, SIsbuffer_load_ushort>;
+def : GINodeEquiv<G_AMDGPU_S_BUFFER_PREFETCH, SIsbuffer_prefetch>;
 
 class GISelSop2Pat <
   SDPatternOperator node,

llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp

@@ -5545,6 +5545,7 @@ const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
   NODE_NAME_CASE(SBUFFER_LOAD_UBYTE)
   NODE_NAME_CASE(SBUFFER_LOAD_SHORT)
   NODE_NAME_CASE(SBUFFER_LOAD_USHORT)
+  NODE_NAME_CASE(SBUFFER_PREFETCH_DATA)
   NODE_NAME_CASE(BUFFER_STORE)
   NODE_NAME_CASE(BUFFER_STORE_BYTE)
   NODE_NAME_CASE(BUFFER_STORE_SHORT)

llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h

@@ -589,6 +589,7 @@ enum NodeType : unsigned {
   SBUFFER_LOAD_UBYTE,
   SBUFFER_LOAD_SHORT,
   SBUFFER_LOAD_USHORT,
+  SBUFFER_PREFETCH_DATA,
   BUFFER_STORE,
   BUFFER_STORE_BYTE,
   BUFFER_STORE_SHORT,

llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp

@@ -5237,7 +5237,8 @@ getConstantZext32Val(Register Reg, const MachineRegisterInfo &MRI) {
 
 InstructionSelector::ComplexRendererFns
 AMDGPUInstructionSelector::selectSMRDBufferImm(MachineOperand &Root) const {
-  std::optional<uint64_t> OffsetVal = getConstantZext32Val(Root.getReg(), *MRI);
+  std::optional<uint64_t> OffsetVal =
+      Root.isImm() ? Root.getImm() : getConstantZext32Val(Root.getReg(), *MRI);
   if (!OffsetVal)
     return {};
 

llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp

@@ -6797,6 +6797,18 @@ bool AMDGPULegalizerInfo::legalizeSBufferLoad(LegalizerHelper &Helper,
   return true;
 }
 
+bool AMDGPULegalizerInfo::legalizeSBufferPrefetch(LegalizerHelper &Helper,
+                                                  MachineInstr &MI) const {
+  MachineIRBuilder &B = Helper.MIRBuilder;
+  GISelChangeObserver &Observer = Helper.Observer;
+  Observer.changingInstr(MI);
+  MI.setDesc(B.getTII().get(AMDGPU::G_AMDGPU_S_BUFFER_PREFETCH));
+  MI.removeOperand(0); // Remove intrinsic ID
+  castBufferRsrcArgToV4I32(MI, B, 0);
+  Observer.changedInstr(MI);
+  return true;
+}
+
 // TODO: Move to selection
 bool AMDGPULegalizerInfo::legalizeTrap(MachineInstr &MI,
                                        MachineRegisterInfo &MRI,
@@ -7485,6 +7497,8 @@ bool AMDGPULegalizerInfo::legalizeIntrinsic(LegalizerHelper &Helper,
   case Intrinsic::amdgcn_permlanex16:
   case Intrinsic::amdgcn_permlane64:
     return legalizeLaneOp(Helper, MI, IntrID);
+  case Intrinsic::amdgcn_s_buffer_prefetch_data:
+    return legalizeSBufferPrefetch(Helper, MI);
   default: {
     if (const AMDGPU::ImageDimIntrinsicInfo *ImageDimIntr =
             AMDGPU::getImageDimIntrinsicInfo(IntrID))

llvm/lib/Target/AMDGPU/AMDGPULegalizerInfo.h

@@ -227,6 +227,8 @@ class AMDGPULegalizerInfo final : public LegalizerInfo {
 
   bool legalizeSBufferLoad(LegalizerHelper &Helper, MachineInstr &MI) const;
 
+  bool legalizeSBufferPrefetch(LegalizerHelper &Helper, MachineInstr &MI) const;
+
   bool legalizeTrap(MachineInstr &MI, MachineRegisterInfo &MRI,
                     MachineIRBuilder &B) const;
   bool legalizeTrapEndpgm(MachineInstr &MI, MachineRegisterInfo &MRI,

llvm/lib/Target/AMDGPU/AMDGPURegisterBankInfo.cpp

@@ -3101,6 +3101,10 @@ void AMDGPURegisterBankInfo::applyMappingImpl(
     applyMappingSBufferLoad(B, OpdMapper);
     return;
   }
+  case AMDGPU::G_AMDGPU_S_BUFFER_PREFETCH:
+    constrainOpWithReadfirstlane(B, MI, 0);
+    constrainOpWithReadfirstlane(B, MI, 2);
+    return;
   case AMDGPU::G_INTRINSIC:
   case AMDGPU::G_INTRINSIC_CONVERGENT: {
     switch (cast<GIntrinsic>(MI).getIntrinsicID()) {
@@ -4464,6 +4468,10 @@ AMDGPURegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
     OpdsMapping[0] = AMDGPU::getValueMapping(ResultBank, Size0);
     break;
   }
+  case AMDGPU::G_AMDGPU_S_BUFFER_PREFETCH:
+    OpdsMapping[0] = getSGPROpMapping(MI.getOperand(0).getReg(), MRI, *TRI);
+    OpdsMapping[2] = getSGPROpMapping(MI.getOperand(2).getReg(), MRI, *TRI);
+    break;
   case AMDGPU::G_INTRINSIC:
   case AMDGPU::G_INTRINSIC_CONVERGENT: {
     switch (cast<GIntrinsic>(MI).getIntrinsicID()) {

llvm/lib/Target/AMDGPU/SIISelLowering.cpp

@@ -1210,9 +1210,13 @@ bool SITargetLowering::getTgtMemIntrinsic(IntrinsicInfo &Info,
         Info.ptrVal = RsrcArg;
     }
 
-    auto *Aux = cast<ConstantInt>(CI.getArgOperand(CI.arg_size() - 1));
-    if (Aux->getZExtValue() & AMDGPU::CPol::VOLATILE)
-      Info.flags |= MachineMemOperand::MOVolatile;
+    bool IsSPrefetch = IntrID == Intrinsic::amdgcn_s_buffer_prefetch_data;
+    if (!IsSPrefetch) {
+      auto *Aux = cast<ConstantInt>(CI.getArgOperand(CI.arg_size() - 1));
+      if (Aux->getZExtValue() & AMDGPU::CPol::VOLATILE)
+        Info.flags |= MachineMemOperand::MOVolatile;
+    }
+
     Info.flags |= MachineMemOperand::MODereferenceable;
     if (ME.onlyReadsMemory()) {
       if (RsrcIntr->IsImage) {
@@ -1251,16 +1255,18 @@ bool SITargetLowering::getTgtMemIntrinsic(IntrinsicInfo &Info,
 
       Info.flags |= MachineMemOperand::MOStore;
     } else {
-      // Atomic or NoReturn Sampler
+      // Atomic, NoReturn Sampler or prefetch
       Info.opc = CI.getType()->isVoidTy() ? ISD::INTRINSIC_VOID :
                                             ISD::INTRINSIC_W_CHAIN;
-      Info.flags |= MachineMemOperand::MOLoad |
-                    MachineMemOperand::MOStore |
-                    MachineMemOperand::MODereferenceable;
+      Info.flags |=
+          MachineMemOperand::MOLoad | MachineMemOperand::MODereferenceable;
+
+      if (!IsSPrefetch)
+        Info.flags |= MachineMemOperand::MOStore;
 
       switch (IntrID) {
       default:
-        if (RsrcIntr->IsImage && BaseOpcode->NoReturn) {
+        if ((RsrcIntr->IsImage && BaseOpcode->NoReturn) || IsSPrefetch) {
           // Fake memory access type for no return sampler intrinsics
           Info.memVT = MVT::i32;
         } else {
@@ -9934,6 +9940,18 @@ SDValue SITargetLowering::LowerINTRINSIC_VOID(SDValue Op,
       return Op.getOperand(0);
     return Op;
   }
+  case Intrinsic::amdgcn_s_buffer_prefetch_data: {
+    SDValue Ops[] = {
+        Chain, bufferRsrcPtrToVector(Op.getOperand(2), DAG),
+        Op.getOperand(3), // offset
+        Op.getOperand(4), // length
+    };
+
+    MemSDNode *M = cast<MemSDNode>(Op);
+    return DAG.getMemIntrinsicNode(AMDGPUISD::SBUFFER_PREFETCH_DATA, DL,
+                                   Op->getVTList(), Ops, M->getMemoryVT(),
+                                   M->getMemOperand());
+  }
   default: {
     if (const AMDGPU::ImageDimIntrinsicInfo *ImageDimIntr =
             AMDGPU::getImageDimIntrinsicInfo(IntrinsicID))

llvm/lib/Target/AMDGPU/SIInstrInfo.td

@@ -312,6 +312,14 @@ class isIntType<ValueType SrcVT> {
   bit ret = !and(SrcVT.isInteger, !ne(SrcVT.Value, i1.Value));
 }
 
+def SDTSBufferPrefetch : SDTypeProfile<0, 3,
+    [SDTCisVT<0, v4i32>, // rsrc
+     SDTCisVT<1, i32>,   // offset(imm)
+     SDTCisVT<2, i32>]>; // length
+
+def SIsbuffer_prefetch : SDNode<"AMDGPUISD::SBUFFER_PREFETCH_DATA", SDTSBufferPrefetch,
+                                [SDNPMayLoad, SDNPMayStore, SDNPMemOperand, SDNPHasChain]>;
+
 //===----------------------------------------------------------------------===//
 // SDNodes PatFrags for loads/stores with a glue input.
 // This is for SDNodes and PatFrag for local loads and stores to

llvm/lib/Target/AMDGPU/SIInstructions.td

@@ -3978,6 +3978,16 @@ def G_AMDGPU_S_BUFFER_LOAD_UBYTE : SBufferLoadInstruction;
 def G_AMDGPU_S_BUFFER_LOAD_SSHORT : SBufferLoadInstruction;
 def G_AMDGPU_S_BUFFER_LOAD_USHORT : SBufferLoadInstruction;
 
+class SBufferPrefetchInstruction : AMDGPUGenericInstruction {
+  let OutOperandList = (outs);
+  let InOperandList = (ins type0:$rsrc, untyped_imm_0:$offset, type1:$len);
+  let hasSideEffects = 0;
+  let mayLoad = 1;
+  let mayStore = 1;
+}
+
+def G_AMDGPU_S_BUFFER_PREFETCH : SBufferPrefetchInstruction;
+
 def G_AMDGPU_S_MUL_U64_U32 : AMDGPUGenericInstruction {
   let OutOperandList = (outs type0:$dst);
   let InOperandList = (ins type0:$src0, type0:$src1);

llvm/lib/Target/AMDGPU/SMInstructions.td

@@ -1171,6 +1171,17 @@ let SubtargetPredicate = isGFX12Plus in {
   def : GCNPat <
     (int_amdgcn_s_prefetch_data (i64 SReg_64:$sbase), imm:$len),
     (S_PREFETCH_DATA $sbase, 0, (i32 SGPR_NULL), (as_i8timm $len))
+
+  >;
+
+  def : GCNPat <
+    (SIsbuffer_prefetch v4i32:$sbase, (SMRDBufferImm i32:$offset), (i32 SReg_32:$len)),
+    (S_BUFFER_PREFETCH_DATA SReg_128:$sbase, i32imm:$offset, $len, 0)
+  >;
+
+  def : GCNPat <
+    (SIsbuffer_prefetch v4i32:$sbase, (SMRDBufferImm i32:$offset), imm:$len),
+    (S_BUFFER_PREFETCH_DATA SReg_128:$sbase, i32imm:$offset, (i32 SGPR_NULL), (as_i8timm $len))
   >;
 } // End let SubtargetPredicate = isGFX12Plus
 

llvm/test/CodeGen/AMDGPU/llvm.amdgcn.s.buffer.prefetch.data.ll

@@ -0,0 +1,50 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -global-isel=0 -march=amdgcn -mcpu=gfx1200 < %s | FileCheck --check-prefix=GCN %s
+; RUN: llc -global-isel=1 -march=amdgcn -mcpu=gfx1200 < %s | FileCheck --check-prefix=GCN %s
+
+declare void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) %rsrc, i32 %offset, i32 %len)
+
+define amdgpu_ps void @buffer_prefetch_data_imm_offset_sgpr_len(ptr addrspace(8) inreg %rsrc, i32 inreg %len) {
+; GCN-LABEL: buffer_prefetch_data_imm_offset_sgpr_len:
+; GCN:       ; %bb.0: ; %entry
+; GCN-NEXT:    s_buffer_prefetch_data s[0:3], 0x80, s4, 0
+; GCN-NEXT:    s_endpgm
+entry:
+  tail call void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) inreg %rsrc, i32 128, i32 %len)
+  ret void
+}
+
+define amdgpu_ps void @buffer_prefetch_data_imm_offset_imm_len(ptr addrspace(8) inreg %rsrc) {
+; GCN-LABEL: buffer_prefetch_data_imm_offset_imm_len:
+; GCN:       ; %bb.0: ; %entry
+; GCN-NEXT:    s_buffer_prefetch_data s[0:3], 0x0, null, 31
+; GCN-NEXT:    s_endpgm
+entry:
+  tail call void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) inreg %rsrc, i32 0, i32 31)
+  ret void
+}
+
+define amdgpu_ps void @buffer_prefetch_data_imm_offset_vgpr_len(ptr addrspace(8) inreg %rsrc, i32 %len) {
+; GCN-LABEL: buffer_prefetch_data_imm_offset_vgpr_len:
+; GCN:       ; %bb.0: ; %entry
+; GCN-NEXT:    v_readfirstlane_b32 s4, v0
+; GCN-NEXT:    s_buffer_prefetch_data s[0:3], 0x80, s4, 0
+; GCN-NEXT:    s_endpgm
+entry:
+  tail call void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) inreg %rsrc, i32 128, i32 %len)
+  ret void
+}
+
+define amdgpu_ps void @buffer_prefetch_data_vgpr_rsrc_imm_offset_sgpr_len(ptr addrspace(8) %rsrc, i32 inreg %len) {
+; GCN-LABEL: buffer_prefetch_data_vgpr_rsrc_imm_offset_sgpr_len:
+; GCN:       ; %bb.0: ; %entry
+; GCN-NEXT:    v_readfirstlane_b32 s4, v0
+; GCN-NEXT:    v_readfirstlane_b32 s5, v1
+; GCN-NEXT:    v_readfirstlane_b32 s6, v2
+; GCN-NEXT:    v_readfirstlane_b32 s7, v3
+; GCN-NEXT:    s_buffer_prefetch_data s[4:7], 0x80, s0, 0
+; GCN-NEXT:    s_endpgm
+entry:
+  tail call void @llvm.amdgcn.s.buffer.prefetch.data(ptr addrspace(8) inreg %rsrc, i32 128, i32 %len)
+  ret void
+}