================ @@ -0,0 +1,81 @@ +//===----------------------------------------------------------------------===// +// +// 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 "PassDetail.h" +#include "mlir/Dialect/Func/IR/FuncOps.h" +#include "mlir/IR/PatternMatch.h" +#include "mlir/Support/LogicalResult.h" +#include "mlir/Transforms/DialectConversion.h" +#include "mlir/Transforms/GreedyPatternRewriteDriver.h" +#include "clang/CIR/Dialect/IR/CIRDialect.h" +#include "clang/CIR/Dialect/Passes.h" +#include "clang/CIR/MissingFeatures.h" +#include "llvm/Support/TimeProfiler.h" + +using namespace mlir; +using namespace cir; + +namespace { + +struct HoistAllocasPass : public HoistAllocasBase<HoistAllocasPass> { + + HoistAllocasPass() = default; + void runOnOperation() override; +}; + +static void process(mlir::ModuleOp mod, cir::FuncOp func) { + if (func.getRegion().empty()) + return; + + // Hoist all static allocas to the entry block. + mlir::Block &entryBlock = func.getRegion().front(); + llvm::SmallVector<cir::AllocaOp> allocas; + func.getBody().walk([&](cir::AllocaOp alloca) { + if (alloca->getBlock() == &entryBlock) + return; + // Don't hoist allocas with dynamic alloca size. + assert(!cir::MissingFeatures::opAllocaDynAllocSize()); + allocas.push_back(alloca); + }); + if (allocas.empty()) + return; + + mlir::Operation *insertPoint = &*entryBlock.begin(); + + for (cir::AllocaOp alloca : allocas) { + // Preserving the `const` attribute on hoisted allocas can cause LLVM to + // incorrectly introduce invariant group metadata in some circumstances. + // The incubator performs some analysis to determine whether the attribute + // can be preserved, but it only runs this analysis when optimizations are + // enabled. Until we start tracking the optimization level, we can just + // always remove the `const` attribute. + assert(!cir::MissingFeatures::optInfoAttr()); + if (alloca.getConstant()) + alloca.setConstant(false); + + alloca->moveBefore(insertPoint); + } +} + +void HoistAllocasPass::runOnOperation() { + llvm::TimeTraceScope scope("Hoist Allocas"); + llvm::SmallVector<Operation *, 16> ops; + + Operation *op = getOperation(); + auto mod = mlir::dyn_cast<mlir::ModuleOp>(op); + if (!mod) + mod = op->getParentOfType<mlir::ModuleOp>(); + + getOperation()->walk([&](cir::FuncOp op) { process(mod, op); }); ---------------- xlauko wrote:
There is probably no need to do recursive walk here? @bcardosolopes can `cir::FuncOp` have nested `cir::FuncOp`? If not this should probably be `PreOrder` walk and return `WalkResult::skip()` from the lambda to not walk its body. https://github.com/llvm/llvm-project/pull/132468 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
