xref: /llvm-project/llvm/lib/Target/AMDGPU/AMDGPUArgumentUsageInfo.cpp (revision 015b640be4c6ce35969be5c38d628feeadb48634)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "AMDGPU.h"
10 #include "AMDGPUArgumentUsageInfo.h"
11 #include "AMDGPUTargetMachine.h"
12 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
13 #include "SIRegisterInfo.h"
14 #include "llvm/Support/NativeFormatting.h"
15 #include "llvm/Support/raw_ostream.h"
16 
17 using namespace llvm;
18 
19 #define DEBUG_TYPE "amdgpu-argument-reg-usage-info"
20 
21 INITIALIZE_PASS(AMDGPUArgumentUsageInfo, DEBUG_TYPE,
22                 "Argument Register Usage Information Storage", false, true)
23 
24 void ArgDescriptor::print(raw_ostream &OS,
25                           const TargetRegisterInfo *TRI) const {
26   if (!isSet()) {
27     OS << "<not set>\n";
28     return;
29   }
30 
31   if (isRegister())
32     OS << "Reg " << printReg(getRegister(), TRI);
33   else
34     OS << "Stack offset " << getStackOffset();
35 
36   if (isMasked()) {
37     OS << " & ";
38     llvm::write_hex(OS, Mask, llvm::HexPrintStyle::PrefixLower);
39   }
40 
41   OS << '\n';
42 }
43 
44 char AMDGPUArgumentUsageInfo::ID = 0;
45 
46 const AMDGPUFunctionArgInfo AMDGPUArgumentUsageInfo::ExternFunctionInfo{};
47 
48 // Hardcoded registers from fixed function ABI
49 const AMDGPUFunctionArgInfo AMDGPUArgumentUsageInfo::FixedABIFunctionInfo
50   = AMDGPUFunctionArgInfo::fixedABILayout();
51 
52 bool AMDGPUArgumentUsageInfo::doInitialization(Module &M) {
53   return false;
54 }
55 
56 bool AMDGPUArgumentUsageInfo::doFinalization(Module &M) {
57   ArgInfoMap.clear();
58   return false;
59 }
60 
61 void AMDGPUArgumentUsageInfo::print(raw_ostream &OS, const Module *M) const {
62   for (const auto &FI : ArgInfoMap) {
63     OS << "Arguments for " << FI.first->getName() << '\n'
64        << "  PrivateSegmentBuffer: " << FI.second.PrivateSegmentBuffer
65        << "  DispatchPtr: " << FI.second.DispatchPtr
66        << "  QueuePtr: " << FI.second.QueuePtr
67        << "  KernargSegmentPtr: " << FI.second.KernargSegmentPtr
68        << "  DispatchID: " << FI.second.DispatchID
69        << "  FlatScratchInit: " << FI.second.FlatScratchInit
70        << "  PrivateSegmentSize: " << FI.second.PrivateSegmentSize
71        << "  WorkGroupIDX: " << FI.second.WorkGroupIDX
72        << "  WorkGroupIDY: " << FI.second.WorkGroupIDY
73        << "  WorkGroupIDZ: " << FI.second.WorkGroupIDZ
74        << "  WorkGroupInfo: " << FI.second.WorkGroupInfo
75        << "  PrivateSegmentWaveByteOffset: "
76           << FI.second.PrivateSegmentWaveByteOffset
77        << "  ImplicitBufferPtr: " << FI.second.ImplicitBufferPtr
78        << "  ImplicitArgPtr: " << FI.second.ImplicitArgPtr
79        << "  WorkItemIDX " << FI.second.WorkItemIDX
80        << "  WorkItemIDY " << FI.second.WorkItemIDY
81        << "  WorkItemIDZ " << FI.second.WorkItemIDZ
82        << '\n';
83   }
84 }
85 
86 std::pair<const ArgDescriptor *, const TargetRegisterClass *>
87 AMDGPUFunctionArgInfo::getPreloadedValue(
88   AMDGPUFunctionArgInfo::PreloadedValue Value) const {
89   switch (Value) {
90   case AMDGPUFunctionArgInfo::PRIVATE_SEGMENT_BUFFER: {
91     return std::make_pair(
92       PrivateSegmentBuffer ? &PrivateSegmentBuffer : nullptr,
93       &AMDGPU::SGPR_128RegClass);
94   }
95   case AMDGPUFunctionArgInfo::IMPLICIT_BUFFER_PTR:
96     return std::make_pair(ImplicitBufferPtr ? &ImplicitBufferPtr : nullptr,
97                           &AMDGPU::SGPR_64RegClass);
98   case AMDGPUFunctionArgInfo::WORKGROUP_ID_X:
99     return std::make_pair(WorkGroupIDX ? &WorkGroupIDX : nullptr,
100                           &AMDGPU::SGPR_32RegClass);
101 
102   case AMDGPUFunctionArgInfo::WORKGROUP_ID_Y:
103     return std::make_pair(WorkGroupIDY ? &WorkGroupIDY : nullptr,
104                           &AMDGPU::SGPR_32RegClass);
105   case AMDGPUFunctionArgInfo::WORKGROUP_ID_Z:
106     return std::make_pair(WorkGroupIDZ ? &WorkGroupIDZ : nullptr,
107                           &AMDGPU::SGPR_32RegClass);
108   case AMDGPUFunctionArgInfo::PRIVATE_SEGMENT_WAVE_BYTE_OFFSET:
109     return std::make_pair(
110       PrivateSegmentWaveByteOffset ? &PrivateSegmentWaveByteOffset : nullptr,
111       &AMDGPU::SGPR_32RegClass);
112   case AMDGPUFunctionArgInfo::KERNARG_SEGMENT_PTR:
113     return std::make_pair(KernargSegmentPtr ? &KernargSegmentPtr : nullptr,
114                           &AMDGPU::SGPR_64RegClass);
115   case AMDGPUFunctionArgInfo::IMPLICIT_ARG_PTR:
116     return std::make_pair(ImplicitArgPtr ? &ImplicitArgPtr : nullptr,
117                           &AMDGPU::SGPR_64RegClass);
118   case AMDGPUFunctionArgInfo::DISPATCH_ID:
119     return std::make_pair(DispatchID ? &DispatchID : nullptr,
120                           &AMDGPU::SGPR_64RegClass);
121   case AMDGPUFunctionArgInfo::FLAT_SCRATCH_INIT:
122     return std::make_pair(FlatScratchInit ? &FlatScratchInit : nullptr,
123                           &AMDGPU::SGPR_64RegClass);
124   case AMDGPUFunctionArgInfo::DISPATCH_PTR:
125     return std::make_pair(DispatchPtr ? &DispatchPtr : nullptr,
126                           &AMDGPU::SGPR_64RegClass);
127   case AMDGPUFunctionArgInfo::QUEUE_PTR:
128     return std::make_pair(QueuePtr ? &QueuePtr : nullptr,
129                           &AMDGPU::SGPR_64RegClass);
130   case AMDGPUFunctionArgInfo::WORKITEM_ID_X:
131     return std::make_pair(WorkItemIDX ? &WorkItemIDX : nullptr,
132                           &AMDGPU::VGPR_32RegClass);
133   case AMDGPUFunctionArgInfo::WORKITEM_ID_Y:
134     return std::make_pair(WorkItemIDY ? &WorkItemIDY : nullptr,
135                           &AMDGPU::VGPR_32RegClass);
136   case AMDGPUFunctionArgInfo::WORKITEM_ID_Z:
137     return std::make_pair(WorkItemIDZ ? &WorkItemIDZ : nullptr,
138                           &AMDGPU::VGPR_32RegClass);
139   }
140   llvm_unreachable("unexpected preloaded value type");
141 }
142 
143 constexpr AMDGPUFunctionArgInfo AMDGPUFunctionArgInfo::fixedABILayout() {
144   AMDGPUFunctionArgInfo AI;
145   AI.PrivateSegmentBuffer = AMDGPU::SGPR0_SGPR1_SGPR2_SGPR3;
146   AI.DispatchPtr = AMDGPU::SGPR4_SGPR5;
147   AI.QueuePtr = AMDGPU::SGPR6_SGPR7;
148 
149   // Do not pass kernarg segment pointer, only pass increment version in its
150   // place.
151   AI.ImplicitArgPtr = AMDGPU::SGPR8_SGPR9;
152   AI.DispatchID = AMDGPU::SGPR10_SGPR11;
153 
154   // Skip FlatScratchInit/PrivateSegmentSize
155   AI.WorkGroupIDX = AMDGPU::SGPR12;
156   AI.WorkGroupIDY = AMDGPU::SGPR13;
157   AI.WorkGroupIDZ = AMDGPU::SGPR14;
158 
159   const unsigned Mask = 0x3ff;
160   AI.WorkItemIDX = ArgDescriptor::createRegister(AMDGPU::VGPR31, Mask);
161   AI.WorkItemIDY = ArgDescriptor::createRegister(AMDGPU::VGPR31, Mask << 10);
162   AI.WorkItemIDZ = ArgDescriptor::createRegister(AMDGPU::VGPR31, Mask << 20);
163   return AI;
164 }
165 
166 const AMDGPUFunctionArgInfo &
167 AMDGPUArgumentUsageInfo::lookupFuncArgInfo(const Function &F) const {
168   auto I = ArgInfoMap.find(&F);
169   if (I == ArgInfoMap.end()) {
170     if (AMDGPUTargetMachine::EnableFixedFunctionABI)
171       return FixedABIFunctionInfo;
172 
173     // Without the fixed ABI, we assume no function has special inputs.
174     assert(F.isDeclaration());
175     return ExternFunctionInfo;
176   }
177 
178   return I->second;
179 }
180