llvm-project/mlir/lib/Target/LLVMIR/Transforms/TargetToDataLayout.cpp
Rolf Morel 4b84223aad
[MLIR][LLVMIR][DLTI] Pass to update #llvm.target's features per relevant backend (#154938)
Modifies `#llvm.target<..., features = $FEATURES>` so that `$FEATURES`
is now an `#llvm.target_features<[...]>` attribute (rather than a
`StringAttr`). This enables the attribute to respond to DLTI queries for
the different target features.

The pass updates the `$FEATURES` attribute of the target attr at name
`llvm.target` in accordance with the (Sub)Target's features that the
relevant LLVM backend knows about.

---

DEMO:
```mlir
module attributes {llvm.target = #llvm.target<triple = "x86_64-unknown-linux",
                                              chip = "skylake"> } {
}
```
by way of `-llvm-target-to-target-features` turns into:
```mlir
module attributes {llvm.target = #llvm.target<triple = "x86_64-unknown-linux",
                                              chip = "skylake", 
                                              features = <["+64bit", "+64bit-mode", "+adx", "+aes", "+allow-light-256-bit", "+avx", "+avx2", "+bmi", "+bmi2", "+clflushopt", "+cmov", "+crc32", "+cx16", "+cx8", "+ermsb", "+f16c", "+false-deps-popcnt", "+fast-15bytenop", "+fast-gather", "+fast-scalar-fsqrt", "+fast-shld-rotate", "+fast-variable-crosslane-shuffle", "+fast-variable-perlane-shuffle", "+fast-vector-fsqrt", "+fma", "+fsgsbase", "+fxsr", "+idivq-to-divl", "+invpcid", "+lzcnt", "+macrofusion", "+mmx", "+movbe", "+no-bypass-delay-blend", "+no-bypass-delay-mov", "+no-bypass-delay-shuffle", "+nopl", "+pclmul", "+popcnt", "+prfchw", "+rdrnd", "+rdseed", "+sahf", "+slow-3ops-lea", "+sse", "+sse2", "+sse3", "+sse4.1", "+sse4.2", "+ssse3", "+vzeroupper", "+x87", "+xsave", "+xsavec", "+xsaveopt", "+xsaves"]>>} {
}
```
2025-08-26 22:12:35 +00:00

63 lines
2.1 KiB
C++

//===- TargetToDataLayout.cpp - extract data layout from TargetMachine ----===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "mlir/Target/LLVMIR/Transforms/Passes.h"
#include "mlir/Target/LLVMIR/Transforms/TargetUtils.h"
#include "mlir/Dialect/DLTI/DLTI.h"
#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
#include "mlir/Target/LLVMIR/Import.h"
namespace mlir {
namespace LLVM {
#define GEN_PASS_DEF_LLVMTARGETTODATALAYOUT
#include "mlir/Target/LLVMIR/Transforms/Passes.h.inc"
} // namespace LLVM
} // namespace mlir
using namespace mlir;
struct TargetToDataLayoutPass
: public LLVM::impl::LLVMTargetToDataLayoutBase<TargetToDataLayoutPass> {
using LLVM::impl::LLVMTargetToDataLayoutBase<
TargetToDataLayoutPass>::LLVMTargetToDataLayoutBase;
void runOnOperation() override {
Operation *op = getOperation();
if (initializeLLVMTargets)
LLVM::detail::initializeBackendsOnce();
auto targetAttr = op->getAttrOfType<LLVM::TargetAttrInterface>(
LLVM::LLVMDialect::getTargetAttrName());
if (!targetAttr) {
op->emitError()
<< "no TargetAttrInterface-implementing attribute at key \""
<< LLVM::LLVMDialect::getTargetAttrName() << "\"";
return signalPassFailure();
}
FailureOr<llvm::DataLayout> dataLayout =
LLVM::detail::getDataLayout(targetAttr);
if (failed(dataLayout)) {
op->emitError() << "failed to obtain llvm::DataLayout for " << targetAttr;
return signalPassFailure();
}
DataLayoutSpecInterface dataLayoutSpec =
mlir::translateDataLayout(dataLayout.value(), &getContext());
if (auto existingDlSpec = op->getAttrOfType<DataLayoutSpecInterface>(
DLTIDialect::kDataLayoutAttrName)) {
dataLayoutSpec = existingDlSpec.combineWith({dataLayoutSpec});
}
op->setAttr(DLTIDialect::kDataLayoutAttrName, dataLayoutSpec);
}
};