xref: /llvm-project/mlir/lib/Conversion/GPUToROCDL/LowerGpuOpsToROCDLOps.cpp (revision 8c3a8d17c8a154894895c48a304a04df9ece4328)
1 //===- LowerGpuOpsToROCDLOps.cpp - MLIR GPU to ROCDL lowering passes ------===//
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 // This file implements a pass to generate ROCDLIR operations for higher-level
10 // GPU operations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "mlir/Conversion/ControlFlowToLLVM/ControlFlowToLLVM.h"
15 #include "mlir/Conversion/GPUToROCDL/GPUToROCDLPass.h"
16 
17 #include "mlir/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.h"
18 #include "mlir/Conversion/ArithToLLVM/ArithToLLVM.h"
19 #include "mlir/Conversion/FuncToLLVM/ConvertFuncToLLVM.h"
20 #include "mlir/Conversion/LLVMCommon/ConversionTarget.h"
21 #include "mlir/Conversion/LLVMCommon/LoweringOptions.h"
22 #include "mlir/Conversion/LLVMCommon/Pattern.h"
23 #include "mlir/Conversion/LLVMCommon/TypeConverter.h"
24 #include "mlir/Conversion/MemRefToLLVM/MemRefToLLVM.h"
25 #include "mlir/Conversion/VectorToLLVM/ConvertVectorToLLVM.h"
26 #include "mlir/Dialect/ControlFlow/IR/ControlFlow.h"
27 #include "mlir/Dialect/MemRef/IR/MemRef.h"
28 #include "mlir/Dialect/Func/IR/FuncOps.h"
29 #include "mlir/Dialect/GPU/IR/GPUDialect.h"
30 #include "mlir/Dialect/GPU/Transforms/Passes.h"
31 #include "mlir/Dialect/LLVMIR/LLVMDialect.h"
32 #include "mlir/Dialect/LLVMIR/ROCDLDialect.h"
33 #include "mlir/Dialect/Math/IR/Math.h"
34 #include "mlir/Dialect/Vector/IR/VectorOps.h"
35 #include "mlir/IR/BuiltinAttributes.h"
36 #include "mlir/Pass/Pass.h"
37 #include "mlir/Transforms/DialectConversion.h"
38 #include "mlir/Transforms/GreedyPatternRewriteDriver.h"
39 #include "llvm/Support/FormatVariadic.h"
40 
41 #include "../GPUCommon/GPUOpsLowering.h"
42 #include "../GPUCommon/IndexIntrinsicsOpLowering.h"
43 #include "../GPUCommon/OpToFuncCallLowering.h"
44 
45 namespace mlir {
46 #define GEN_PASS_DEF_CONVERTGPUOPSTOROCDLOPS
47 #include "mlir/Conversion/Passes.h.inc"
48 } // namespace mlir
49 
50 using namespace mlir;
51 
52 /// Returns true if the given `gpu.func` can be safely called using the bare
53 /// pointer calling convention.
54 static bool canBeCalledWithBarePointers(gpu::GPUFuncOp func) {
55   bool canBeBare = true;
56   for (Type type : func.getArgumentTypes())
57     if (auto memrefTy = dyn_cast<BaseMemRefType>(type))
58       canBeBare &= LLVMTypeConverter::canConvertToBarePtr(memrefTy);
59   return canBeBare;
60 }
61 
62 namespace {
63 
64 /// Import the GPU Ops to ROCDL Patterns.
65 #include "GPUToROCDL.cpp.inc"
66 
67 // A pass that replaces all occurrences of GPU device operations with their
68 // corresponding ROCDL equivalent.
69 //
70 // This pass only handles device code and is not meant to be run on GPU host
71 // code.
72 struct LowerGpuOpsToROCDLOpsPass
73     : public impl::ConvertGpuOpsToROCDLOpsBase<LowerGpuOpsToROCDLOpsPass> {
74   LowerGpuOpsToROCDLOpsPass() = default;
75   LowerGpuOpsToROCDLOpsPass(const std::string &chipset, unsigned indexBitwidth,
76                             bool useBarePtrCallConv,
77                             gpu::amd::Runtime runtime) {
78     if (this->chipset.getNumOccurrences() == 0)
79       this->chipset = chipset;
80     if (this->indexBitwidth.getNumOccurrences() == 0)
81       this->indexBitwidth = indexBitwidth;
82     if (this->useBarePtrCallConv.getNumOccurrences() == 0)
83       this->useBarePtrCallConv = useBarePtrCallConv;
84     if (this->runtime.getNumOccurrences() == 0)
85       this->runtime = runtime;
86   }
87 
88   void runOnOperation() override {
89     gpu::GPUModuleOp m = getOperation();
90     MLIRContext *ctx = m.getContext();
91 
92     // Request C wrapper emission.
93     for (auto func : m.getOps<func::FuncOp>()) {
94       func->setAttr(LLVM::LLVMDialect::getEmitCWrapperAttrName(),
95                     UnitAttr::get(ctx));
96     }
97 
98     FailureOr<amdgpu::Chipset> maybeChipset = amdgpu::Chipset::parse(chipset);
99     if (failed(maybeChipset)) {
100       emitError(UnknownLoc::get(ctx), "Invalid chipset name: " + chipset);
101       return signalPassFailure();
102     }
103 
104     /// Customize the bitwidth used for the device side index computations.
105     LowerToLLVMOptions options(
106         ctx, DataLayout(cast<DataLayoutOpInterface>(m.getOperation())));
107     if (indexBitwidth != kDeriveIndexBitwidthFromDataLayout)
108       options.overrideIndexBitwidth(indexBitwidth);
109     options.useOpaquePointers = useOpaquePointers;
110 
111     if (useBarePtrCallConv) {
112       options.useBarePtrCallConv = true;
113       WalkResult canUseBarePointers =
114           m.walk([](gpu::GPUFuncOp func) -> WalkResult {
115             if (canBeCalledWithBarePointers(func))
116               return WalkResult::advance();
117             return WalkResult::interrupt();
118           });
119       if (canUseBarePointers.wasInterrupted()) {
120         emitError(UnknownLoc::get(ctx),
121                   "bare pointer calling convention requires all memrefs to "
122                   "have static shape and use the identity map");
123         return signalPassFailure();
124       }
125     }
126 
127     // Apply in-dialect lowering. In-dialect lowering will replace
128     // ops which need to be lowered further, which is not supported by a
129     // single conversion pass.
130     {
131       RewritePatternSet patterns(ctx);
132       populateGpuRewritePatterns(patterns);
133       (void)applyPatternsAndFoldGreedily(m, std::move(patterns));
134     }
135 
136     LLVMTypeConverter converter(ctx, options);
137     populateGpuMemorySpaceAttributeConversions(
138         converter, [](gpu::AddressSpace space) {
139           switch (space) {
140           case gpu::AddressSpace::Global:
141             return 1;
142           case gpu::AddressSpace::Workgroup:
143             return 3;
144           case gpu::AddressSpace::Private:
145             return 5;
146           }
147           llvm_unreachable("unknown address space enum value");
148           return 0;
149         });
150 
151     RewritePatternSet llvmPatterns(ctx);
152 
153     mlir::arith::populateArithToLLVMConversionPatterns(converter, llvmPatterns);
154     populateAMDGPUToROCDLConversionPatterns(converter, llvmPatterns,
155                                             *maybeChipset);
156     populateVectorToLLVMConversionPatterns(converter, llvmPatterns);
157     cf::populateControlFlowToLLVMConversionPatterns(converter, llvmPatterns);
158     populateFuncToLLVMConversionPatterns(converter, llvmPatterns);
159     populateFinalizeMemRefToLLVMConversionPatterns(converter, llvmPatterns);
160     populateGpuToROCDLConversionPatterns(converter, llvmPatterns, runtime);
161     LLVMConversionTarget target(getContext());
162     configureGpuToROCDLConversionLegality(target);
163     if (failed(applyPartialConversion(m, target, std::move(llvmPatterns))))
164       signalPassFailure();
165 
166     // Manually rewrite known block size attributes so the LLVMIR translation
167     // infrastructure can pick them up.
168     m.walk([ctx](LLVM::LLVMFuncOp op) {
169       if (auto blockSizes = dyn_cast_or_null<DenseI32ArrayAttr>(
170               op->removeAttr(gpu::GPUFuncOp::getKnownBlockSizeAttrName()))) {
171         op->setAttr(ROCDL::ROCDLDialect::getReqdWorkGroupSizeAttrName(),
172                     blockSizes);
173         // Also set up the rocdl.flat_work_group_size attribute to prevent
174         // conflicting metadata.
175         uint32_t flatSize = 1;
176         for (uint32_t size : blockSizes.asArrayRef()) {
177           flatSize *= size;
178         }
179         StringAttr flatSizeAttr =
180             StringAttr::get(ctx, Twine(flatSize) + "," + Twine(flatSize));
181         op->setAttr(ROCDL::ROCDLDialect::getFlatWorkGroupSizeAttrName(),
182                     flatSizeAttr);
183       }
184     });
185   }
186 };
187 
188 } // namespace
189 
190 void mlir::configureGpuToROCDLConversionLegality(ConversionTarget &target) {
191   target.addIllegalOp<func::FuncOp>();
192   target.addLegalDialect<::mlir::LLVM::LLVMDialect>();
193   target.addLegalDialect<ROCDL::ROCDLDialect>();
194   target.addIllegalDialect<gpu::GPUDialect>();
195   target.addIllegalOp<LLVM::CosOp, LLVM::ExpOp, LLVM::Exp2Op, LLVM::FAbsOp,
196                       LLVM::FCeilOp, LLVM::FFloorOp, LLVM::LogOp, LLVM::Log10Op,
197                       LLVM::Log2Op, LLVM::PowOp, LLVM::SinOp, LLVM::SqrtOp>();
198 
199   // TODO: Remove once we support replacing non-root ops.
200   target.addLegalOp<gpu::YieldOp, gpu::GPUModuleOp, gpu::ModuleEndOp>();
201 }
202 
203 template <typename OpTy>
204 static void populateOpPatterns(LLVMTypeConverter &converter,
205                                RewritePatternSet &patterns, StringRef f32Func,
206                                StringRef f64Func) {
207   patterns.add<ScalarizeVectorOpLowering<OpTy>>(converter);
208   patterns.add<OpToFuncCallLowering<OpTy>>(converter, f32Func, f64Func);
209 }
210 
211 void mlir::populateGpuToROCDLConversionPatterns(
212     LLVMTypeConverter &converter, RewritePatternSet &patterns,
213     mlir::gpu::amd::Runtime runtime) {
214   using mlir::gpu::amd::Runtime;
215 
216   populateWithGenerated(patterns);
217   patterns
218       .add<GPUIndexIntrinsicOpLowering<gpu::ThreadIdOp, ROCDL::ThreadIdXOp,
219                                        ROCDL::ThreadIdYOp, ROCDL::ThreadIdZOp>>(
220           converter, gpu::GPUFuncOp::getKnownBlockSizeAttrName());
221   patterns.add<GPUIndexIntrinsicOpLowering<
222       gpu::BlockIdOp, ROCDL::BlockIdXOp, ROCDL::BlockIdYOp, ROCDL::BlockIdZOp>>(
223       converter, gpu::GPUFuncOp::getKnownGridSizeAttrName());
224   patterns
225       .add<GPUIndexIntrinsicOpLowering<gpu::BlockDimOp, ROCDL::BlockDimXOp,
226                                        ROCDL::BlockDimYOp, ROCDL::BlockDimZOp>,
227            GPUIndexIntrinsicOpLowering<gpu::GridDimOp, ROCDL::GridDimXOp,
228                                        ROCDL::GridDimYOp, ROCDL::GridDimZOp>,
229            GPUReturnOpLowering>(converter);
230   patterns.add<GPUFuncOpLowering>(
231       converter,
232       /*allocaAddrSpace=*/ROCDL::ROCDLDialect::kPrivateMemoryAddressSpace,
233       /*workgroupAddrSpace=*/ROCDL::ROCDLDialect::kSharedMemoryAddressSpace,
234       StringAttr::get(&converter.getContext(),
235                       ROCDL::ROCDLDialect::getKernelFuncAttrName()));
236   if (Runtime::HIP == runtime) {
237     patterns.add<GPUPrintfOpToHIPLowering>(converter);
238   } else if (Runtime::OpenCL == runtime) {
239     // Use address space = 4 to match the OpenCL definition of printf()
240     patterns.add<GPUPrintfOpToLLVMCallLowering>(converter, /*addressSpace=*/4);
241   }
242 
243   populateOpPatterns<math::AbsFOp>(converter, patterns, "__ocml_fabs_f32",
244                                    "__ocml_fabs_f64");
245   populateOpPatterns<math::AtanOp>(converter, patterns, "__ocml_atan_f32",
246                                    "__ocml_atan_f64");
247   populateOpPatterns<math::Atan2Op>(converter, patterns, "__ocml_atan2_f32",
248                                     "__ocml_atan2_f64");
249   populateOpPatterns<math::CbrtOp>(converter, patterns, "__ocml_cbrt_f32",
250                                    "__ocml_cbrt_f64");
251   populateOpPatterns<math::CeilOp>(converter, patterns, "__ocml_ceil_f32",
252                                    "__ocml_ceil_f64");
253   populateOpPatterns<math::CosOp>(converter, patterns, "__ocml_cos_f32",
254                                   "__ocml_cos_f64");
255   populateOpPatterns<math::ExpOp>(converter, patterns, "__ocml_exp_f32",
256                                   "__ocml_exp_f64");
257   populateOpPatterns<math::Exp2Op>(converter, patterns, "__ocml_exp2_f32",
258                                    "__ocml_exp2_f64");
259   populateOpPatterns<math::ExpM1Op>(converter, patterns, "__ocml_expm1_f32",
260                                     "__ocml_expm1_f64");
261   populateOpPatterns<math::FloorOp>(converter, patterns, "__ocml_floor_f32",
262                                     "__ocml_floor_f64");
263   populateOpPatterns<math::LogOp>(converter, patterns, "__ocml_log_f32",
264                                   "__ocml_log_f64");
265   populateOpPatterns<math::Log10Op>(converter, patterns, "__ocml_log10_f32",
266                                     "__ocml_log10_f64");
267   populateOpPatterns<math::Log1pOp>(converter, patterns, "__ocml_log1p_f32",
268                                     "__ocml_log1p_f64");
269   populateOpPatterns<math::Log2Op>(converter, patterns, "__ocml_log2_f32",
270                                    "__ocml_log2_f64");
271   populateOpPatterns<math::PowFOp>(converter, patterns, "__ocml_pow_f32",
272                                    "__ocml_pow_f64");
273   populateOpPatterns<math::RsqrtOp>(converter, patterns, "__ocml_rsqrt_f32",
274                                     "__ocml_rsqrt_f64");
275   populateOpPatterns<math::SinOp>(converter, patterns, "__ocml_sin_f32",
276                                   "__ocml_sin_f64");
277   populateOpPatterns<math::SqrtOp>(converter, patterns, "__ocml_sqrt_f32",
278                                    "__ocml_sqrt_f64");
279   populateOpPatterns<math::TanhOp>(converter, patterns, "__ocml_tanh_f32",
280                                    "__ocml_tanh_f64");
281   populateOpPatterns<math::TanOp>(converter, patterns, "__ocml_tan_f32",
282                                   "__ocml_tan_f64");
283   populateOpPatterns<math::ErfOp>(converter, patterns, "__ocml_erf_f32",
284                                   "__ocml_erf_f64");
285 }
286 
287 std::unique_ptr<OperationPass<gpu::GPUModuleOp>>
288 mlir::createLowerGpuOpsToROCDLOpsPass(const std::string &chipset,
289                                       unsigned indexBitwidth,
290                                       bool useBarePtrCallConv,
291                                       gpu::amd::Runtime runtime) {
292   return std::make_unique<LowerGpuOpsToROCDLOpsPass>(
293       chipset, indexBitwidth, useBarePtrCallConv, runtime);
294 }
295