forked from OSchip/llvm-project
95eaca3e0f
To accomplish this, moving forward users will need to provide a legalization target that defines what operations are legal for the conversion. A target can mark an operation as legal by providing a specific legalization action. The initial actions are:
* Legal
- This action signals that every instance of the given operation is legal,
i.e. any combination of attributes, operands, types, etc. is valid.
* Dynamic
- This action signals that only some instances of a given operation are legal. This
allows for defining fine-tune constraints, like say std.add is only legal when
operating on 32-bit integers.
An example target is shown below:
struct MyTarget : public ConversionTarget {
MyTarget(MLIRContext &ctx) : ConversionTarget(ctx) {
// All operations in the LLVM dialect are legal.
addLegalDialect<LLVMDialect>();
// std.constant op is always legal on this target.
addLegalOp<ConstantOp>();
// std.return op has dynamic legality constraints.
addDynamicallyLegalOp<ReturnOp>();
}
/// Implement the custom legalization handler to handle
/// std.return.
bool isLegal(Operation *op) override {
// Process the dynamic handling for a std.return op (and any others that were
// marked "dynamic").
...
}
};
PiperOrigin-RevId: 251289374
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| CMakeLists.txt | ||