xref: /llvm-project/mlir/lib/Conversion/GPUToROCDL/LowerGpuOpsToROCDLOps.cpp (revision 4f1e244eb5b53e3ccced518048d8311e88e510d0)
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 = type.dyn_cast<BaseMemRefType>())
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 
110     if (useBarePtrCallConv) {
111       options.useBarePtrCallConv = true;
112       WalkResult canUseBarePointers =
113           m.walk([](gpu::GPUFuncOp func) -> WalkResult {
114             if (canBeCalledWithBarePointers(func))
115               return WalkResult::advance();
116             return WalkResult::interrupt();
117           });
118       if (canUseBarePointers.wasInterrupted()) {
119         emitError(UnknownLoc::get(ctx),
120                   "bare pointer calling convention requires all memrefs to "
121                   "have static shape and use the identity map");
122         return signalPassFailure();
123       }
124     }
125 
126     // Apply in-dialect lowering. In-dialect lowering will replace
127     // ops which need to be lowered further, which is not supported by a
128     // single conversion pass.
129     {
130       RewritePatternSet patterns(ctx);
131       populateGpuRewritePatterns(patterns);
132       (void)applyPatternsAndFoldGreedily(m, std::move(patterns));
133     }
134 
135     // Apply memory space lowering. The target uses 3 for workgroup memory and 5
136     // for private memory.
137     {
138       RewritePatternSet patterns(ctx);
139       TypeConverter typeConverter;
140       typeConverter.addConversion([](Type t) { return t; });
141       gpu::populateMemorySpaceAttributeTypeConversions(
142           typeConverter, [](gpu::AddressSpace space) {
143             switch (space) {
144             case gpu::AddressSpace::Global:
145               return 1;
146             case gpu::AddressSpace::Workgroup:
147               return 3;
148             case gpu::AddressSpace::Private:
149               return 5;
150             }
151             llvm_unreachable("unknown address space enum value");
152             return 0;
153           });
154       ConversionTarget target(getContext());
155       gpu::populateLowerMemorySpaceOpLegality(target);
156       gpu::populateMemorySpaceLoweringPatterns(typeConverter, patterns);
157       if (failed(applyFullConversion(m, target, std::move(patterns))))
158         return signalPassFailure();
159     }
160 
161     LLVMTypeConverter converter(ctx, options);
162     RewritePatternSet llvmPatterns(ctx);
163 
164     mlir::arith::populateArithToLLVMConversionPatterns(converter, llvmPatterns);
165     populateAMDGPUToROCDLConversionPatterns(converter, llvmPatterns,
166                                             *maybeChipset);
167     populateVectorToLLVMConversionPatterns(converter, llvmPatterns);
168     cf::populateControlFlowToLLVMConversionPatterns(converter, llvmPatterns);
169     populateFuncToLLVMConversionPatterns(converter, llvmPatterns);
170     populateMemRefToLLVMConversionPatterns(converter, llvmPatterns);
171     populateGpuToROCDLConversionPatterns(converter, llvmPatterns, runtime);
172     LLVMConversionTarget target(getContext());
173     configureGpuToROCDLConversionLegality(target);
174     if (failed(applyPartialConversion(m, target, std::move(llvmPatterns))))
175       signalPassFailure();
176 
177     // Manually rewrite known block size attributes so the LLVMIR translation
178     // infrastructure can pick them up.
179     m.walk([ctx](LLVM::LLVMFuncOp op) {
180       if (auto blockSizes =
181               op->removeAttr(gpu::GPUFuncOp::getKnownBlockSizeAttrName())
182                   .dyn_cast_or_null<DenseI32ArrayAttr>()) {
183         op->setAttr(ROCDL::ROCDLDialect::getReqdWorkGroupSizeAttrName(),
184                     blockSizes);
185         // Also set up the rocdl.flat_work_group_size attribute to prevent
186         // conflicting metadata.
187         uint32_t flatSize = 1;
188         for (uint32_t size : blockSizes.asArrayRef()) {
189           flatSize *= size;
190         }
191         StringAttr flatSizeAttr =
192             StringAttr::get(ctx, Twine(flatSize) + "," + Twine(flatSize));
193         op->setAttr(ROCDL::ROCDLDialect::getFlatWorkGroupSizeAttrName(),
194                     flatSizeAttr);
195       }
196     });
197   }
198 };
199 
200 } // namespace
201 
202 void mlir::configureGpuToROCDLConversionLegality(ConversionTarget &target) {
203   target.addIllegalOp<func::FuncOp>();
204   target.addLegalDialect<::mlir::LLVM::LLVMDialect>();
205   target.addLegalDialect<ROCDL::ROCDLDialect>();
206   target.addIllegalDialect<gpu::GPUDialect>();
207   target.addIllegalOp<LLVM::CosOp, LLVM::ExpOp, LLVM::Exp2Op, LLVM::FAbsOp,
208                       LLVM::FCeilOp, LLVM::FFloorOp, LLVM::LogOp, LLVM::Log10Op,
209                       LLVM::Log2Op, LLVM::PowOp, LLVM::SinOp, LLVM::SqrtOp>();
210 
211   // TODO: Remove once we support replacing non-root ops.
212   target.addLegalOp<gpu::YieldOp, gpu::GPUModuleOp, gpu::ModuleEndOp>();
213 }
214 
215 template <typename OpTy>
216 static void populateOpPatterns(LLVMTypeConverter &converter,
217                                RewritePatternSet &patterns, StringRef f32Func,
218                                StringRef f64Func) {
219   patterns.add<ScalarizeVectorOpLowering<OpTy>>(converter);
220   patterns.add<OpToFuncCallLowering<OpTy>>(converter, f32Func, f64Func);
221 }
222 
223 void mlir::populateGpuToROCDLConversionPatterns(
224     LLVMTypeConverter &converter, RewritePatternSet &patterns,
225     mlir::gpu::amd::Runtime runtime) {
226   using mlir::gpu::amd::Runtime;
227 
228   populateWithGenerated(patterns);
229   patterns
230       .add<GPUIndexIntrinsicOpLowering<gpu::ThreadIdOp, ROCDL::ThreadIdXOp,
231                                        ROCDL::ThreadIdYOp, ROCDL::ThreadIdZOp>>(
232           converter, gpu::GPUFuncOp::getKnownBlockSizeAttrName());
233   patterns.add<GPUIndexIntrinsicOpLowering<
234       gpu::BlockIdOp, ROCDL::BlockIdXOp, ROCDL::BlockIdYOp, ROCDL::BlockIdZOp>>(
235       converter, gpu::GPUFuncOp::getKnownGridSizeAttrName());
236   patterns
237       .add<GPUIndexIntrinsicOpLowering<gpu::BlockDimOp, ROCDL::BlockDimXOp,
238                                        ROCDL::BlockDimYOp, ROCDL::BlockDimZOp>,
239            GPUIndexIntrinsicOpLowering<gpu::GridDimOp, ROCDL::GridDimXOp,
240                                        ROCDL::GridDimYOp, ROCDL::GridDimZOp>,
241            GPUReturnOpLowering>(converter);
242   patterns.add<GPUFuncOpLowering>(
243       converter,
244       /*allocaAddrSpace=*/ROCDL::ROCDLDialect::kPrivateMemoryAddressSpace,
245       /*workgroupAddrSpace=*/ROCDL::ROCDLDialect::kSharedMemoryAddressSpace,
246       StringAttr::get(&converter.getContext(),
247                       ROCDL::ROCDLDialect::getKernelFuncAttrName()));
248   if (Runtime::HIP == runtime) {
249     patterns.add<GPUPrintfOpToHIPLowering>(converter);
250   } else if (Runtime::OpenCL == runtime) {
251     // Use address space = 4 to match the OpenCL definition of printf()
252     patterns.add<GPUPrintfOpToLLVMCallLowering>(converter, /*addressSpace=*/4);
253   }
254 
255   populateOpPatterns<math::AbsFOp>(converter, patterns, "__ocml_fabs_f32",
256                                    "__ocml_fabs_f64");
257   populateOpPatterns<math::AtanOp>(converter, patterns, "__ocml_atan_f32",
258                                    "__ocml_atan_f64");
259   populateOpPatterns<math::Atan2Op>(converter, patterns, "__ocml_atan2_f32",
260                                     "__ocml_atan2_f64");
261   populateOpPatterns<math::CbrtOp>(converter, patterns, "__ocml_cbrt_f32",
262                                    "__ocml_cbrt_f64");
263   populateOpPatterns<math::CeilOp>(converter, patterns, "__ocml_ceil_f32",
264                                    "__ocml_ceil_f64");
265   populateOpPatterns<math::CosOp>(converter, patterns, "__ocml_cos_f32",
266                                   "__ocml_cos_f64");
267   populateOpPatterns<math::ExpOp>(converter, patterns, "__ocml_exp_f32",
268                                   "__ocml_exp_f64");
269   populateOpPatterns<math::Exp2Op>(converter, patterns, "__ocml_exp2_f32",
270                                    "__ocml_exp2_f64");
271   populateOpPatterns<math::ExpM1Op>(converter, patterns, "__ocml_expm1_f32",
272                                     "__ocml_expm1_f64");
273   populateOpPatterns<math::FloorOp>(converter, patterns, "__ocml_floor_f32",
274                                     "__ocml_floor_f64");
275   populateOpPatterns<math::LogOp>(converter, patterns, "__ocml_log_f32",
276                                   "__ocml_log_f64");
277   populateOpPatterns<math::Log10Op>(converter, patterns, "__ocml_log10_f32",
278                                     "__ocml_log10_f64");
279   populateOpPatterns<math::Log1pOp>(converter, patterns, "__ocml_log1p_f32",
280                                     "__ocml_log1p_f64");
281   populateOpPatterns<math::Log2Op>(converter, patterns, "__ocml_log2_f32",
282                                    "__ocml_log2_f64");
283   populateOpPatterns<math::PowFOp>(converter, patterns, "__ocml_pow_f32",
284                                    "__ocml_pow_f64");
285   populateOpPatterns<math::RsqrtOp>(converter, patterns, "__ocml_rsqrt_f32",
286                                     "__ocml_rsqrt_f64");
287   populateOpPatterns<math::SinOp>(converter, patterns, "__ocml_sin_f32",
288                                   "__ocml_sin_f64");
289   populateOpPatterns<math::SqrtOp>(converter, patterns, "__ocml_sqrt_f32",
290                                    "__ocml_sqrt_f64");
291   populateOpPatterns<math::TanhOp>(converter, patterns, "__ocml_tanh_f32",
292                                    "__ocml_tanh_f64");
293   populateOpPatterns<math::TanOp>(converter, patterns, "__ocml_tan_f32",
294                                   "__ocml_tan_f64");
295 }
296 
297 std::unique_ptr<OperationPass<gpu::GPUModuleOp>>
298 mlir::createLowerGpuOpsToROCDLOpsPass(const std::string &chipset,
299                                       unsigned indexBitwidth,
300                                       bool useBarePtrCallConv,
301                                       gpu::amd::Runtime runtime) {
302   return std::make_unique<LowerGpuOpsToROCDLOpsPass>(
303       chipset, indexBitwidth, useBarePtrCallConv, runtime);
304 }
305