1 //===- TestClone.cpp - Pass to test operation cloning  --------------------===//
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 "TestDialect.h"
10 #include "mlir/IR/BuiltinOps.h"
11 #include "mlir/Pass/Pass.h"
12 
13 using namespace mlir;
14 
15 namespace {
16 
17 /// This is a test pass which clones the body of a function. Specifically
18 /// this pass replaces f(x) to instead return f(f(x)) in which the cloned body
19 /// takes the result of the first operation return as an input.
20 struct ClonePass
21     : public PassWrapper<ClonePass, InterfacePass<FunctionOpInterface>> {
22   MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(ClonePass)
23 
24   StringRef getArgument() const final { return "test-clone"; }
25   StringRef getDescription() const final { return "Test clone of op"; }
26   void runOnOperation() override {
27     FunctionOpInterface op = getOperation();
28 
29     // Limit testing to ops with only one region.
30     if (op->getNumRegions() != 1)
31       return;
32 
33     Region &region = op->getRegion(0);
34     if (!region.hasOneBlock())
35       return;
36 
37     Block &regionEntry = region.front();
38     Operation *terminator = regionEntry.getTerminator();
39 
40     // Only handle functions whose returns match the inputs.
41     if (terminator->getNumOperands() != regionEntry.getNumArguments())
42       return;
43 
44     BlockAndValueMapping map;
45     for (auto tup :
46          llvm::zip(terminator->getOperands(), regionEntry.getArguments())) {
47       if (std::get<0>(tup).getType() != std::get<1>(tup).getType())
48         return;
49       map.map(std::get<1>(tup), std::get<0>(tup));
50     }
51 
52     OpBuilder builder(op->getContext());
53     builder.setInsertionPointToEnd(&regionEntry);
54     SmallVector<Operation *> toClone;
55     for (Operation &inst : regionEntry)
56       toClone.push_back(&inst);
57     for (Operation *inst : toClone)
58       builder.clone(*inst, map);
59     terminator->erase();
60   }
61 };
62 } // namespace
63 
64 namespace mlir {
65 void registerCloneTestPasses() { PassRegistration<ClonePass>(); }
66 } // namespace mlir
67