c41b16c26b
This aligns the printer with the parser contract: the operation isn't part of the user-controllable part of the syntax. Differential Revision: https://reviews.llvm.org/D108804
2250 lines
84 KiB
C++
2250 lines
84 KiB
C++
//===- SCF.cpp - Structured Control Flow Operations -----------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "mlir/Dialect/SCF/SCF.h"
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#include "mlir/Dialect/MemRef/IR/MemRef.h"
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#include "mlir/Dialect/StandardOps/IR/Ops.h"
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#include "mlir/Dialect/Tensor/IR/Tensor.h"
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#include "mlir/IR/BlockAndValueMapping.h"
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#include "mlir/IR/PatternMatch.h"
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#include "mlir/Support/MathExtras.h"
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#include "mlir/Transforms/InliningUtils.h"
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using namespace mlir;
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using namespace mlir::scf;
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#include "mlir/Dialect/SCF/SCFOpsDialect.cpp.inc"
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//===----------------------------------------------------------------------===//
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// SCFDialect Dialect Interfaces
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//===----------------------------------------------------------------------===//
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namespace {
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struct SCFInlinerInterface : public DialectInlinerInterface {
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using DialectInlinerInterface::DialectInlinerInterface;
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// We don't have any special restrictions on what can be inlined into
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// destination regions (e.g. while/conditional bodies). Always allow it.
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bool isLegalToInline(Region *dest, Region *src, bool wouldBeCloned,
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BlockAndValueMapping &valueMapping) const final {
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return true;
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}
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// Operations in scf dialect are always legal to inline since they are
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// pure.
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bool isLegalToInline(Operation *, Region *, bool,
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BlockAndValueMapping &) const final {
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return true;
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}
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// Handle the given inlined terminator by replacing it with a new operation
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// as necessary. Required when the region has only one block.
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void handleTerminator(Operation *op,
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ArrayRef<Value> valuesToRepl) const final {
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auto retValOp = dyn_cast<scf::YieldOp>(op);
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if (!retValOp)
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return;
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for (auto retValue : llvm::zip(valuesToRepl, retValOp.getOperands())) {
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std::get<0>(retValue).replaceAllUsesWith(std::get<1>(retValue));
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}
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}
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};
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} // end anonymous namespace
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//===----------------------------------------------------------------------===//
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// SCFDialect
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//===----------------------------------------------------------------------===//
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void SCFDialect::initialize() {
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addOperations<
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#define GET_OP_LIST
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#include "mlir/Dialect/SCF/SCFOps.cpp.inc"
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>();
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addInterfaces<SCFInlinerInterface>();
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}
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/// Default callback for IfOp builders. Inserts a yield without arguments.
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void mlir::scf::buildTerminatedBody(OpBuilder &builder, Location loc) {
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builder.create<scf::YieldOp>(loc);
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}
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//===----------------------------------------------------------------------===//
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// ExecuteRegionOp
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//===----------------------------------------------------------------------===//
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/// Replaces the given op with the contents of the given single-block region,
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/// using the operands of the block terminator to replace operation results.
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static void replaceOpWithRegion(PatternRewriter &rewriter, Operation *op,
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Region ®ion, ValueRange blockArgs = {}) {
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assert(llvm::hasSingleElement(region) && "expected single-region block");
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Block *block = ®ion.front();
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Operation *terminator = block->getTerminator();
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ValueRange results = terminator->getOperands();
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rewriter.mergeBlockBefore(block, op, blockArgs);
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rewriter.replaceOp(op, results);
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rewriter.eraseOp(terminator);
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}
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///
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/// (ssa-id `=`)? `execute_region` `->` function-result-type `{`
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/// block+
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/// `}`
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///
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/// Example:
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/// scf.execute_region -> i32 {
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/// %idx = load %rI[%i] : memref<128xi32>
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/// return %idx : i32
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/// }
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///
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static ParseResult parseExecuteRegionOp(OpAsmParser &parser,
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OperationState &result) {
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if (parser.parseOptionalArrowTypeList(result.types))
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return failure();
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// Introduce the body region and parse it.
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Region *body = result.addRegion();
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if (parser.parseRegion(*body, /*arguments=*/{}, /*argTypes=*/{}) ||
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parser.parseOptionalAttrDict(result.attributes))
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return failure();
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return success();
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}
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static void print(OpAsmPrinter &p, ExecuteRegionOp op) {
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p.printOptionalArrowTypeList(op.getResultTypes());
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p.printRegion(op.region(),
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/*printEntryBlockArgs=*/false,
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/*printBlockTerminators=*/true);
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p.printOptionalAttrDict(op->getAttrs());
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}
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static LogicalResult verify(ExecuteRegionOp op) {
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if (op.region().empty())
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return op.emitOpError("region needs to have at least one block");
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if (op.region().front().getNumArguments() > 0)
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return op.emitOpError("region cannot have any arguments");
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return success();
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}
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// Inline an ExecuteRegionOp if it only contains one block.
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// "test.foo"() : () -> ()
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// %v = scf.execute_region -> i64 {
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// %x = "test.val"() : () -> i64
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// scf.yield %x : i64
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// }
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// "test.bar"(%v) : (i64) -> ()
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//
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// becomes
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//
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// "test.foo"() : () -> ()
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// %x = "test.val"() : () -> i64
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// "test.bar"(%x) : (i64) -> ()
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//
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struct SingleBlockExecuteInliner : public OpRewritePattern<ExecuteRegionOp> {
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using OpRewritePattern<ExecuteRegionOp>::OpRewritePattern;
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LogicalResult matchAndRewrite(ExecuteRegionOp op,
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PatternRewriter &rewriter) const override {
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if (!llvm::hasSingleElement(op.region()))
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return failure();
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replaceOpWithRegion(rewriter, op, op.region());
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return success();
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}
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};
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// Inline an ExecuteRegionOp if its parent can contain multiple blocks.
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// TODO generalize the conditions for operations which can be inlined into.
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// func @func_execute_region_elim() {
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// "test.foo"() : () -> ()
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// %v = scf.execute_region -> i64 {
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// %c = "test.cmp"() : () -> i1
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// cond_br %c, ^bb2, ^bb3
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// ^bb2:
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// %x = "test.val1"() : () -> i64
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// br ^bb4(%x : i64)
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// ^bb3:
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// %y = "test.val2"() : () -> i64
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// br ^bb4(%y : i64)
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// ^bb4(%z : i64):
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// scf.yield %z : i64
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// }
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// "test.bar"(%v) : (i64) -> ()
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// return
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// }
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//
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// becomes
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//
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// func @func_execute_region_elim() {
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// "test.foo"() : () -> ()
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// %c = "test.cmp"() : () -> i1
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// cond_br %c, ^bb1, ^bb2
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// ^bb1: // pred: ^bb0
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// %x = "test.val1"() : () -> i64
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// br ^bb3(%x : i64)
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// ^bb2: // pred: ^bb0
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// %y = "test.val2"() : () -> i64
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// br ^bb3(%y : i64)
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// ^bb3(%z: i64): // 2 preds: ^bb1, ^bb2
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// "test.bar"(%z) : (i64) -> ()
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// return
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// }
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//
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struct MultiBlockExecuteInliner : public OpRewritePattern<ExecuteRegionOp> {
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using OpRewritePattern<ExecuteRegionOp>::OpRewritePattern;
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LogicalResult matchAndRewrite(ExecuteRegionOp op,
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PatternRewriter &rewriter) const override {
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if (!isa<FuncOp, ExecuteRegionOp>(op->getParentOp()))
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return failure();
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Block *prevBlock = op->getBlock();
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Block *postBlock = rewriter.splitBlock(prevBlock, op->getIterator());
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rewriter.setInsertionPointToEnd(prevBlock);
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rewriter.create<BranchOp>(op.getLoc(), &op.region().front());
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for (Block &blk : op.region()) {
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if (YieldOp yieldOp = dyn_cast<YieldOp>(blk.getTerminator())) {
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rewriter.setInsertionPoint(yieldOp);
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rewriter.create<BranchOp>(yieldOp.getLoc(), postBlock,
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yieldOp.results());
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rewriter.eraseOp(yieldOp);
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}
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}
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rewriter.inlineRegionBefore(op.region(), postBlock);
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SmallVector<Value> blockArgs;
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for (auto res : op.getResults())
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blockArgs.push_back(postBlock->addArgument(res.getType()));
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rewriter.replaceOp(op, blockArgs);
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return success();
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}
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};
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void ExecuteRegionOp::getCanonicalizationPatterns(RewritePatternSet &results,
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MLIRContext *context) {
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results.add<SingleBlockExecuteInliner, MultiBlockExecuteInliner>(context);
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}
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//===----------------------------------------------------------------------===//
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// ConditionOp
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//===----------------------------------------------------------------------===//
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MutableOperandRange
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ConditionOp::getMutableSuccessorOperands(Optional<unsigned> index) {
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// Pass all operands except the condition to the successor region.
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return argsMutable();
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}
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//===----------------------------------------------------------------------===//
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// ForOp
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//===----------------------------------------------------------------------===//
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void ForOp::build(OpBuilder &builder, OperationState &result, Value lb,
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Value ub, Value step, ValueRange iterArgs,
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BodyBuilderFn bodyBuilder) {
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result.addOperands({lb, ub, step});
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result.addOperands(iterArgs);
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for (Value v : iterArgs)
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result.addTypes(v.getType());
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Region *bodyRegion = result.addRegion();
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bodyRegion->push_back(new Block);
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Block &bodyBlock = bodyRegion->front();
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bodyBlock.addArgument(builder.getIndexType());
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for (Value v : iterArgs)
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bodyBlock.addArgument(v.getType());
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// Create the default terminator if the builder is not provided and if the
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// iteration arguments are not provided. Otherwise, leave this to the caller
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// because we don't know which values to return from the loop.
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if (iterArgs.empty() && !bodyBuilder) {
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ForOp::ensureTerminator(*bodyRegion, builder, result.location);
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} else if (bodyBuilder) {
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OpBuilder::InsertionGuard guard(builder);
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builder.setInsertionPointToStart(&bodyBlock);
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bodyBuilder(builder, result.location, bodyBlock.getArgument(0),
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bodyBlock.getArguments().drop_front());
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}
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}
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static LogicalResult verify(ForOp op) {
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if (auto cst = op.step().getDefiningOp<ConstantIndexOp>())
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if (cst.getValue() <= 0)
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return op.emitOpError("constant step operand must be positive");
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// Check that the body defines as single block argument for the induction
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// variable.
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auto *body = op.getBody();
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if (!body->getArgument(0).getType().isIndex())
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return op.emitOpError(
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"expected body first argument to be an index argument for "
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"the induction variable");
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auto opNumResults = op.getNumResults();
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if (opNumResults == 0)
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return success();
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// If ForOp defines values, check that the number and types of
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// the defined values match ForOp initial iter operands and backedge
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// basic block arguments.
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if (op.getNumIterOperands() != opNumResults)
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return op.emitOpError(
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"mismatch in number of loop-carried values and defined values");
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if (op.getNumRegionIterArgs() != opNumResults)
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return op.emitOpError(
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"mismatch in number of basic block args and defined values");
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auto iterOperands = op.getIterOperands();
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auto iterArgs = op.getRegionIterArgs();
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auto opResults = op.getResults();
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unsigned i = 0;
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for (auto e : llvm::zip(iterOperands, iterArgs, opResults)) {
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if (std::get<0>(e).getType() != std::get<2>(e).getType())
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return op.emitOpError() << "types mismatch between " << i
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<< "th iter operand and defined value";
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if (std::get<1>(e).getType() != std::get<2>(e).getType())
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return op.emitOpError() << "types mismatch between " << i
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<< "th iter region arg and defined value";
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i++;
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}
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return RegionBranchOpInterface::verifyTypes(op);
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}
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/// Prints the initialization list in the form of
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/// <prefix>(%inner = %outer, %inner2 = %outer2, <...>)
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/// where 'inner' values are assumed to be region arguments and 'outer' values
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/// are regular SSA values.
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static void printInitializationList(OpAsmPrinter &p,
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Block::BlockArgListType blocksArgs,
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ValueRange initializers,
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StringRef prefix = "") {
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assert(blocksArgs.size() == initializers.size() &&
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"expected same length of arguments and initializers");
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if (initializers.empty())
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return;
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p << prefix << '(';
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llvm::interleaveComma(llvm::zip(blocksArgs, initializers), p, [&](auto it) {
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p << std::get<0>(it) << " = " << std::get<1>(it);
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});
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p << ")";
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}
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static void print(OpAsmPrinter &p, ForOp op) {
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p << " " << op.getInductionVar() << " = " << op.lowerBound() << " to "
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<< op.upperBound() << " step " << op.step();
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printInitializationList(p, op.getRegionIterArgs(), op.getIterOperands(),
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" iter_args");
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if (!op.getIterOperands().empty())
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p << " -> (" << op.getIterOperands().getTypes() << ')';
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p.printRegion(op.region(),
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/*printEntryBlockArgs=*/false,
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/*printBlockTerminators=*/op.hasIterOperands());
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p.printOptionalAttrDict(op->getAttrs());
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}
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static ParseResult parseForOp(OpAsmParser &parser, OperationState &result) {
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auto &builder = parser.getBuilder();
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OpAsmParser::OperandType inductionVariable, lb, ub, step;
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// Parse the induction variable followed by '='.
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if (parser.parseRegionArgument(inductionVariable) || parser.parseEqual())
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return failure();
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// Parse loop bounds.
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Type indexType = builder.getIndexType();
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if (parser.parseOperand(lb) ||
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parser.resolveOperand(lb, indexType, result.operands) ||
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parser.parseKeyword("to") || parser.parseOperand(ub) ||
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parser.resolveOperand(ub, indexType, result.operands) ||
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parser.parseKeyword("step") || parser.parseOperand(step) ||
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parser.resolveOperand(step, indexType, result.operands))
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return failure();
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// Parse the optional initial iteration arguments.
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SmallVector<OpAsmParser::OperandType, 4> regionArgs, operands;
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SmallVector<Type, 4> argTypes;
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regionArgs.push_back(inductionVariable);
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if (succeeded(parser.parseOptionalKeyword("iter_args"))) {
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// Parse assignment list and results type list.
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if (parser.parseAssignmentList(regionArgs, operands) ||
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parser.parseArrowTypeList(result.types))
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return failure();
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// Resolve input operands.
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for (auto operandType : llvm::zip(operands, result.types))
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if (parser.resolveOperand(std::get<0>(operandType),
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std::get<1>(operandType), result.operands))
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return failure();
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}
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// Induction variable.
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argTypes.push_back(indexType);
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// Loop carried variables
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argTypes.append(result.types.begin(), result.types.end());
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// Parse the body region.
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Region *body = result.addRegion();
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if (regionArgs.size() != argTypes.size())
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return parser.emitError(
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parser.getNameLoc(),
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"mismatch in number of loop-carried values and defined values");
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if (parser.parseRegion(*body, regionArgs, argTypes))
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return failure();
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ForOp::ensureTerminator(*body, builder, result.location);
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// Parse the optional attribute list.
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if (parser.parseOptionalAttrDict(result.attributes))
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return failure();
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return success();
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}
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Region &ForOp::getLoopBody() { return region(); }
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bool ForOp::isDefinedOutsideOfLoop(Value value) {
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return !region().isAncestor(value.getParentRegion());
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}
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LogicalResult ForOp::moveOutOfLoop(ArrayRef<Operation *> ops) {
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for (auto *op : ops)
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op->moveBefore(*this);
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return success();
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}
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ForOp mlir::scf::getForInductionVarOwner(Value val) {
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auto ivArg = val.dyn_cast<BlockArgument>();
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if (!ivArg)
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return ForOp();
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assert(ivArg.getOwner() && "unlinked block argument");
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auto *containingOp = ivArg.getOwner()->getParentOp();
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return dyn_cast_or_null<ForOp>(containingOp);
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}
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/// Return operands used when entering the region at 'index'. These operands
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/// correspond to the loop iterator operands, i.e., those excluding the
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/// induction variable. LoopOp only has one region, so 0 is the only valid value
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/// for `index`.
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OperandRange ForOp::getSuccessorEntryOperands(unsigned index) {
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assert(index == 0 && "invalid region index");
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// The initial operands map to the loop arguments after the induction
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// variable.
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return initArgs();
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}
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/// Given the region at `index`, or the parent operation if `index` is None,
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/// return the successor regions. These are the regions that may be selected
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/// during the flow of control. `operands` is a set of optional attributes that
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/// correspond to a constant value for each operand, or null if that operand is
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/// not a constant.
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void ForOp::getSuccessorRegions(Optional<unsigned> index,
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ArrayRef<Attribute> operands,
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SmallVectorImpl<RegionSuccessor> ®ions) {
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// If the predecessor is the ForOp, branch into the body using the iterator
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// arguments.
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if (!index.hasValue()) {
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regions.push_back(RegionSuccessor(&getLoopBody(), getRegionIterArgs()));
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return;
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}
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// Otherwise, the loop may branch back to itself or the parent operation.
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assert(index.getValue() == 0 && "expected loop region");
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regions.push_back(RegionSuccessor(&getLoopBody(), getRegionIterArgs()));
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regions.push_back(RegionSuccessor(getResults()));
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}
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void ForOp::getNumRegionInvocations(ArrayRef<Attribute> operands,
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SmallVectorImpl<int64_t> &countPerRegion) {
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assert(countPerRegion.empty());
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countPerRegion.resize(1);
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auto lb = operands[0].dyn_cast_or_null<IntegerAttr>();
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auto ub = operands[1].dyn_cast_or_null<IntegerAttr>();
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auto step = operands[2].dyn_cast_or_null<IntegerAttr>();
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// Loop bounds are not known statically.
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if (!lb || !ub || !step || step.getValue().getSExtValue() == 0) {
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countPerRegion[0] = -1;
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return;
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}
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countPerRegion[0] =
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ceilDiv(ub.getValue().getSExtValue() - lb.getValue().getSExtValue(),
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step.getValue().getSExtValue());
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}
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LoopNest mlir::scf::buildLoopNest(
|
|
OpBuilder &builder, Location loc, ValueRange lbs, ValueRange ubs,
|
|
ValueRange steps, ValueRange iterArgs,
|
|
function_ref<ValueVector(OpBuilder &, Location, ValueRange, ValueRange)>
|
|
bodyBuilder) {
|
|
assert(lbs.size() == ubs.size() &&
|
|
"expected the same number of lower and upper bounds");
|
|
assert(lbs.size() == steps.size() &&
|
|
"expected the same number of lower bounds and steps");
|
|
|
|
// If there are no bounds, call the body-building function and return early.
|
|
if (lbs.empty()) {
|
|
ValueVector results =
|
|
bodyBuilder ? bodyBuilder(builder, loc, ValueRange(), iterArgs)
|
|
: ValueVector();
|
|
assert(results.size() == iterArgs.size() &&
|
|
"loop nest body must return as many values as loop has iteration "
|
|
"arguments");
|
|
return LoopNest();
|
|
}
|
|
|
|
// First, create the loop structure iteratively using the body-builder
|
|
// callback of `ForOp::build`. Do not create `YieldOp`s yet.
|
|
OpBuilder::InsertionGuard guard(builder);
|
|
SmallVector<scf::ForOp, 4> loops;
|
|
SmallVector<Value, 4> ivs;
|
|
loops.reserve(lbs.size());
|
|
ivs.reserve(lbs.size());
|
|
ValueRange currentIterArgs = iterArgs;
|
|
Location currentLoc = loc;
|
|
for (unsigned i = 0, e = lbs.size(); i < e; ++i) {
|
|
auto loop = builder.create<scf::ForOp>(
|
|
currentLoc, lbs[i], ubs[i], steps[i], currentIterArgs,
|
|
[&](OpBuilder &nestedBuilder, Location nestedLoc, Value iv,
|
|
ValueRange args) {
|
|
ivs.push_back(iv);
|
|
// It is safe to store ValueRange args because it points to block
|
|
// arguments of a loop operation that we also own.
|
|
currentIterArgs = args;
|
|
currentLoc = nestedLoc;
|
|
});
|
|
// Set the builder to point to the body of the newly created loop. We don't
|
|
// do this in the callback because the builder is reset when the callback
|
|
// returns.
|
|
builder.setInsertionPointToStart(loop.getBody());
|
|
loops.push_back(loop);
|
|
}
|
|
|
|
// For all loops but the innermost, yield the results of the nested loop.
|
|
for (unsigned i = 0, e = loops.size() - 1; i < e; ++i) {
|
|
builder.setInsertionPointToEnd(loops[i].getBody());
|
|
builder.create<scf::YieldOp>(loc, loops[i + 1].getResults());
|
|
}
|
|
|
|
// In the body of the innermost loop, call the body building function if any
|
|
// and yield its results.
|
|
builder.setInsertionPointToStart(loops.back().getBody());
|
|
ValueVector results = bodyBuilder
|
|
? bodyBuilder(builder, currentLoc, ivs,
|
|
loops.back().getRegionIterArgs())
|
|
: ValueVector();
|
|
assert(results.size() == iterArgs.size() &&
|
|
"loop nest body must return as many values as loop has iteration "
|
|
"arguments");
|
|
builder.setInsertionPointToEnd(loops.back().getBody());
|
|
builder.create<scf::YieldOp>(loc, results);
|
|
|
|
// Return the loops.
|
|
LoopNest res;
|
|
res.loops.assign(loops.begin(), loops.end());
|
|
return res;
|
|
}
|
|
|
|
LoopNest mlir::scf::buildLoopNest(
|
|
OpBuilder &builder, Location loc, ValueRange lbs, ValueRange ubs,
|
|
ValueRange steps,
|
|
function_ref<void(OpBuilder &, Location, ValueRange)> bodyBuilder) {
|
|
// Delegate to the main function by wrapping the body builder.
|
|
return buildLoopNest(builder, loc, lbs, ubs, steps, llvm::None,
|
|
[&bodyBuilder](OpBuilder &nestedBuilder,
|
|
Location nestedLoc, ValueRange ivs,
|
|
ValueRange) -> ValueVector {
|
|
if (bodyBuilder)
|
|
bodyBuilder(nestedBuilder, nestedLoc, ivs);
|
|
return {};
|
|
});
|
|
}
|
|
|
|
namespace {
|
|
// Fold away ForOp iter arguments when:
|
|
// 1) The op yields the iter arguments.
|
|
// 2) The iter arguments have no use and the corresponding outer region
|
|
// iterators (inputs) are yielded.
|
|
// 3) The iter arguments have no use and the corresponding (operation) results
|
|
// have no use.
|
|
//
|
|
// These arguments must be defined outside of
|
|
// the ForOp region and can just be forwarded after simplifying the op inits,
|
|
// yields and returns.
|
|
//
|
|
// The implementation uses `mergeBlockBefore` to steal the content of the
|
|
// original ForOp and avoid cloning.
|
|
struct ForOpIterArgsFolder : public OpRewritePattern<scf::ForOp> {
|
|
using OpRewritePattern<scf::ForOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(scf::ForOp forOp,
|
|
PatternRewriter &rewriter) const final {
|
|
bool canonicalize = false;
|
|
Block &block = forOp.region().front();
|
|
auto yieldOp = cast<scf::YieldOp>(block.getTerminator());
|
|
|
|
// An internal flat vector of block transfer
|
|
// arguments `newBlockTransferArgs` keeps the 1-1 mapping of original to
|
|
// transformed block argument mappings. This plays the role of a
|
|
// BlockAndValueMapping for the particular use case of calling into
|
|
// `mergeBlockBefore`.
|
|
SmallVector<bool, 4> keepMask;
|
|
keepMask.reserve(yieldOp.getNumOperands());
|
|
SmallVector<Value, 4> newBlockTransferArgs, newIterArgs, newYieldValues,
|
|
newResultValues;
|
|
newBlockTransferArgs.reserve(1 + forOp.getNumIterOperands());
|
|
newBlockTransferArgs.push_back(Value()); // iv placeholder with null value
|
|
newIterArgs.reserve(forOp.getNumIterOperands());
|
|
newYieldValues.reserve(yieldOp.getNumOperands());
|
|
newResultValues.reserve(forOp.getNumResults());
|
|
for (auto it : llvm::zip(forOp.getIterOperands(), // iter from outside
|
|
forOp.getRegionIterArgs(), // iter inside region
|
|
forOp.getResults(), // op results
|
|
yieldOp.getOperands() // iter yield
|
|
)) {
|
|
// Forwarded is `true` when:
|
|
// 1) The region `iter` argument is yielded.
|
|
// 2) The region `iter` argument has no use, and the corresponding iter
|
|
// operand (input) is yielded.
|
|
// 3) The region `iter` argument has no use, and the corresponding op
|
|
// result has no use.
|
|
bool forwarded = ((std::get<1>(it) == std::get<3>(it)) ||
|
|
(std::get<1>(it).use_empty() &&
|
|
(std::get<0>(it) == std::get<3>(it) ||
|
|
std::get<2>(it).use_empty())));
|
|
keepMask.push_back(!forwarded);
|
|
canonicalize |= forwarded;
|
|
if (forwarded) {
|
|
newBlockTransferArgs.push_back(std::get<0>(it));
|
|
newResultValues.push_back(std::get<0>(it));
|
|
continue;
|
|
}
|
|
newIterArgs.push_back(std::get<0>(it));
|
|
newYieldValues.push_back(std::get<3>(it));
|
|
newBlockTransferArgs.push_back(Value()); // placeholder with null value
|
|
newResultValues.push_back(Value()); // placeholder with null value
|
|
}
|
|
|
|
if (!canonicalize)
|
|
return failure();
|
|
|
|
scf::ForOp newForOp = rewriter.create<scf::ForOp>(
|
|
forOp.getLoc(), forOp.lowerBound(), forOp.upperBound(), forOp.step(),
|
|
newIterArgs);
|
|
Block &newBlock = newForOp.region().front();
|
|
|
|
// Replace the null placeholders with newly constructed values.
|
|
newBlockTransferArgs[0] = newBlock.getArgument(0); // iv
|
|
for (unsigned idx = 0, collapsedIdx = 0, e = newResultValues.size();
|
|
idx != e; ++idx) {
|
|
Value &blockTransferArg = newBlockTransferArgs[1 + idx];
|
|
Value &newResultVal = newResultValues[idx];
|
|
assert((blockTransferArg && newResultVal) ||
|
|
(!blockTransferArg && !newResultVal));
|
|
if (!blockTransferArg) {
|
|
blockTransferArg = newForOp.getRegionIterArgs()[collapsedIdx];
|
|
newResultVal = newForOp.getResult(collapsedIdx++);
|
|
}
|
|
}
|
|
|
|
Block &oldBlock = forOp.region().front();
|
|
assert(oldBlock.getNumArguments() == newBlockTransferArgs.size() &&
|
|
"unexpected argument size mismatch");
|
|
|
|
// No results case: the scf::ForOp builder already created a zero
|
|
// result terminator. Merge before this terminator and just get rid of the
|
|
// original terminator that has been merged in.
|
|
if (newIterArgs.empty()) {
|
|
auto newYieldOp = cast<scf::YieldOp>(newBlock.getTerminator());
|
|
rewriter.mergeBlockBefore(&oldBlock, newYieldOp, newBlockTransferArgs);
|
|
rewriter.eraseOp(newBlock.getTerminator()->getPrevNode());
|
|
rewriter.replaceOp(forOp, newResultValues);
|
|
return success();
|
|
}
|
|
|
|
// No terminator case: merge and rewrite the merged terminator.
|
|
auto cloneFilteredTerminator = [&](scf::YieldOp mergedTerminator) {
|
|
OpBuilder::InsertionGuard g(rewriter);
|
|
rewriter.setInsertionPoint(mergedTerminator);
|
|
SmallVector<Value, 4> filteredOperands;
|
|
filteredOperands.reserve(newResultValues.size());
|
|
for (unsigned idx = 0, e = keepMask.size(); idx < e; ++idx)
|
|
if (keepMask[idx])
|
|
filteredOperands.push_back(mergedTerminator.getOperand(idx));
|
|
rewriter.create<scf::YieldOp>(mergedTerminator.getLoc(),
|
|
filteredOperands);
|
|
};
|
|
|
|
rewriter.mergeBlocks(&oldBlock, &newBlock, newBlockTransferArgs);
|
|
auto mergedYieldOp = cast<scf::YieldOp>(newBlock.getTerminator());
|
|
cloneFilteredTerminator(mergedYieldOp);
|
|
rewriter.eraseOp(mergedYieldOp);
|
|
rewriter.replaceOp(forOp, newResultValues);
|
|
return success();
|
|
}
|
|
};
|
|
|
|
/// Rewriting pattern that erases loops that are known not to iterate and
|
|
/// replaces single-iteration loops with their bodies.
|
|
struct SimplifyTrivialLoops : public OpRewritePattern<ForOp> {
|
|
using OpRewritePattern<ForOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(ForOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
// If the upper bound is the same as the lower bound, the loop does not
|
|
// iterate, just remove it.
|
|
if (op.lowerBound() == op.upperBound()) {
|
|
rewriter.replaceOp(op, op.getIterOperands());
|
|
return success();
|
|
}
|
|
|
|
auto lb = op.lowerBound().getDefiningOp<ConstantOp>();
|
|
auto ub = op.upperBound().getDefiningOp<ConstantOp>();
|
|
if (!lb || !ub)
|
|
return failure();
|
|
|
|
// If the loop is known to have 0 iterations, remove it.
|
|
llvm::APInt lbValue = lb.getValue().cast<IntegerAttr>().getValue();
|
|
llvm::APInt ubValue = ub.getValue().cast<IntegerAttr>().getValue();
|
|
if (lbValue.sge(ubValue)) {
|
|
rewriter.replaceOp(op, op.getIterOperands());
|
|
return success();
|
|
}
|
|
|
|
auto step = op.step().getDefiningOp<ConstantOp>();
|
|
if (!step)
|
|
return failure();
|
|
|
|
// If the loop is known to have 1 iteration, inline its body and remove the
|
|
// loop.
|
|
llvm::APInt stepValue = step.getValue().cast<IntegerAttr>().getValue();
|
|
if ((lbValue + stepValue).sge(ubValue)) {
|
|
SmallVector<Value, 4> blockArgs;
|
|
blockArgs.reserve(op.getNumIterOperands() + 1);
|
|
blockArgs.push_back(op.lowerBound());
|
|
llvm::append_range(blockArgs, op.getIterOperands());
|
|
replaceOpWithRegion(rewriter, op, op.getLoopBody(), blockArgs);
|
|
return success();
|
|
}
|
|
|
|
return failure();
|
|
}
|
|
};
|
|
|
|
/// Perform a replacement of one iter OpOperand of an scf.for to the
|
|
/// `replacement` value which is expected to be the source of a tensor.cast.
|
|
/// tensor.cast ops are inserted inside the block to account for the type cast.
|
|
static ForOp replaceTensorCastForOpIterArg(PatternRewriter &rewriter,
|
|
OpOperand &operand,
|
|
Value replacement) {
|
|
Type oldType = operand.get().getType(), newType = replacement.getType();
|
|
assert(oldType.isa<RankedTensorType>() && newType.isa<RankedTensorType>() &&
|
|
"expected ranked tensor types");
|
|
|
|
// 1. Create new iter operands, exactly 1 is replaced.
|
|
ForOp forOp = cast<ForOp>(operand.getOwner());
|
|
assert(operand.getOperandNumber() >= forOp.getNumControlOperands() &&
|
|
"expected an iter OpOperand");
|
|
if (operand.get().getType() == replacement.getType())
|
|
return forOp;
|
|
SmallVector<Value> newIterOperands;
|
|
for (OpOperand &opOperand : forOp.getIterOpOperands()) {
|
|
if (opOperand.getOperandNumber() == operand.getOperandNumber()) {
|
|
newIterOperands.push_back(replacement);
|
|
continue;
|
|
}
|
|
newIterOperands.push_back(opOperand.get());
|
|
}
|
|
|
|
// 2. Create the new forOp shell.
|
|
scf::ForOp newForOp = rewriter.create<scf::ForOp>(
|
|
forOp.getLoc(), forOp.lowerBound(), forOp.upperBound(), forOp.step(),
|
|
newIterOperands);
|
|
Block &newBlock = newForOp.region().front();
|
|
SmallVector<Value, 4> newBlockTransferArgs(newBlock.getArguments().begin(),
|
|
newBlock.getArguments().end());
|
|
|
|
// 3. Inject an incoming cast op at the beginning of the block for the bbArg
|
|
// corresponding to the `replacement` value.
|
|
OpBuilder::InsertionGuard g(rewriter);
|
|
rewriter.setInsertionPoint(&newBlock, newBlock.begin());
|
|
BlockArgument newRegionIterArg = newForOp.getRegionIterArgForOpOperand(
|
|
newForOp->getOpOperand(operand.getOperandNumber()));
|
|
Value castIn = rewriter.create<tensor::CastOp>(newForOp.getLoc(), oldType,
|
|
newRegionIterArg);
|
|
newBlockTransferArgs[newRegionIterArg.getArgNumber()] = castIn;
|
|
|
|
// 4. Steal the old block ops, mapping to the newBlockTransferArgs.
|
|
Block &oldBlock = forOp.region().front();
|
|
rewriter.mergeBlocks(&oldBlock, &newBlock, newBlockTransferArgs);
|
|
|
|
// 5. Inject an outgoing cast op at the end of the block and yield it instead.
|
|
auto clonedYieldOp = cast<scf::YieldOp>(newBlock.getTerminator());
|
|
rewriter.setInsertionPoint(clonedYieldOp);
|
|
unsigned yieldIdx =
|
|
newRegionIterArg.getArgNumber() - forOp.getNumInductionVars();
|
|
Value castOut = rewriter.create<tensor::CastOp>(
|
|
newForOp.getLoc(), newType, clonedYieldOp.getOperand(yieldIdx));
|
|
SmallVector<Value> newYieldOperands = clonedYieldOp.getOperands();
|
|
newYieldOperands[yieldIdx] = castOut;
|
|
rewriter.create<scf::YieldOp>(newForOp.getLoc(), newYieldOperands);
|
|
rewriter.eraseOp(clonedYieldOp);
|
|
|
|
// 6. Inject an outgoing cast op after the forOp.
|
|
rewriter.setInsertionPointAfter(newForOp);
|
|
SmallVector<Value> newResults = newForOp.getResults();
|
|
newResults[yieldIdx] = rewriter.create<tensor::CastOp>(
|
|
newForOp.getLoc(), oldType, newResults[yieldIdx]);
|
|
|
|
return newForOp;
|
|
}
|
|
|
|
/// Fold scf.for iter_arg/result pairs that go through incoming/ougoing
|
|
/// a tensor.cast op pair so as to pull the tensor.cast inside the scf.for:
|
|
///
|
|
/// ```
|
|
/// %0 = tensor.cast %t0 : tensor<32x1024xf32> to tensor<?x?xf32>
|
|
/// %1 = scf.for %i = %c0 to %c1024 step %c32 iter_args(%iter_t0 = %0)
|
|
/// -> (tensor<?x?xf32>) {
|
|
/// %2 = call @do(%iter_t0) : (tensor<?x?xf32>) -> tensor<?x?xf32>
|
|
/// scf.yield %2 : tensor<?x?xf32>
|
|
/// }
|
|
/// %2 = tensor.cast %1 : tensor<?x?xf32> to tensor<32x1024xf32>
|
|
/// use_of(%2)
|
|
/// ```
|
|
///
|
|
/// folds into:
|
|
///
|
|
/// ```
|
|
/// %0 = scf.for %arg2 = %c0 to %c1024 step %c32 iter_args(%arg3 = %arg0)
|
|
/// -> (tensor<32x1024xf32>) {
|
|
/// %2 = tensor.cast %arg3 : tensor<32x1024xf32> to tensor<?x?xf32>
|
|
/// %3 = call @do(%2) : (tensor<?x?xf32>) -> tensor<?x?xf32>
|
|
/// %4 = tensor.cast %3 : tensor<?x?xf32> to tensor<32x1024xf32>
|
|
/// scf.yield %4 : tensor<32x1024xf32>
|
|
/// }
|
|
/// use_of(%0)
|
|
/// ```
|
|
struct ForOpTensorCastFolder : public OpRewritePattern<ForOp> {
|
|
using OpRewritePattern<ForOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(ForOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
for (auto it : llvm::zip(op.getIterOpOperands(), op.getResults())) {
|
|
OpOperand &iterOpOperand = std::get<0>(it);
|
|
auto incomingCast = iterOpOperand.get().getDefiningOp<tensor::CastOp>();
|
|
if (!incomingCast)
|
|
continue;
|
|
if (!std::get<1>(it).hasOneUse())
|
|
continue;
|
|
auto outgoingCastOp =
|
|
dyn_cast<tensor::CastOp>(*std::get<1>(it).user_begin());
|
|
if (!outgoingCastOp)
|
|
continue;
|
|
|
|
// Must be a tensor.cast op pair with matching types.
|
|
if (outgoingCastOp.getResult().getType() !=
|
|
incomingCast.source().getType())
|
|
continue;
|
|
|
|
// Create a new ForOp with that iter operand replaced.
|
|
auto newForOp = replaceTensorCastForOpIterArg(rewriter, iterOpOperand,
|
|
incomingCast.source());
|
|
|
|
// Insert outgoing cast and use it to replace the corresponding result.
|
|
rewriter.setInsertionPointAfter(newForOp);
|
|
SmallVector<Value> replacements = newForOp.getResults();
|
|
unsigned returnIdx =
|
|
iterOpOperand.getOperandNumber() - op.getNumControlOperands();
|
|
replacements[returnIdx] = rewriter.create<tensor::CastOp>(
|
|
op.getLoc(), incomingCast.dest().getType(), replacements[returnIdx]);
|
|
rewriter.replaceOp(op, replacements);
|
|
return success();
|
|
}
|
|
return failure();
|
|
}
|
|
};
|
|
|
|
/// Canonicalize the iter_args of an scf::ForOp that involve a tensor_load and
|
|
/// for which only the last loop iteration is actually visible outside of the
|
|
/// loop. The canonicalization looks for a pattern such as:
|
|
/// ```
|
|
/// %t0 = ... : tensor_type
|
|
/// %0 = scf.for ... iter_args(%bb0 : %t0) -> (tensor_type) {
|
|
/// ...
|
|
/// // %m is either buffer_cast(%bb00) or defined above the loop
|
|
/// %m... : memref_type
|
|
/// ... // uses of %m with potential inplace updates
|
|
/// %new_tensor = tensor_load %m : memref_type
|
|
/// ...
|
|
/// scf.yield %new_tensor : tensor_type
|
|
/// }
|
|
/// ```
|
|
///
|
|
/// `%bb0` may have either 0 or 1 use. If it has 1 use it must be exactly a
|
|
/// `%m = buffer_cast %bb0` op that feeds into the yielded `tensor_load`
|
|
/// op.
|
|
///
|
|
/// If no aliasing write to the memref `%m`, from which `%new_tensor`is loaded,
|
|
/// occurs between tensor_load and yield then the value %0 visible outside of
|
|
/// the loop is the last `tensor_load` produced in the loop.
|
|
///
|
|
/// For now, we approximate the absence of aliasing by only supporting the case
|
|
/// when the tensor_load is the operation immediately preceding the yield.
|
|
///
|
|
/// The canonicalization rewrites the pattern as:
|
|
/// ```
|
|
/// // %m is either a buffer_cast or defined above
|
|
/// %m... : memref_type
|
|
/// scf.for ... iter_args(%bb0 : %t0) -> (tensor_type) {
|
|
/// ... // uses of %m with potential inplace updates
|
|
/// scf.yield %bb0: tensor_type
|
|
/// }
|
|
/// %0 = tensor_load %m : memref_type
|
|
/// ```
|
|
///
|
|
/// A later bbArg canonicalization will further rewrite as:
|
|
/// ```
|
|
/// // %m is either a buffer_cast or defined above
|
|
/// %m... : memref_type
|
|
/// scf.for ... { // no iter_args
|
|
/// ... // uses of %m with potential inplace updates
|
|
/// }
|
|
/// %0 = tensor_load %m : memref_type
|
|
/// ```
|
|
struct LastTensorLoadCanonicalization : public OpRewritePattern<ForOp> {
|
|
using OpRewritePattern<ForOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(ForOp forOp,
|
|
PatternRewriter &rewriter) const override {
|
|
assert(std::next(forOp.region().begin()) == forOp.region().end() &&
|
|
"unexpected multiple blocks");
|
|
|
|
Location loc = forOp.getLoc();
|
|
DenseMap<Value, Value> replacements;
|
|
for (BlockArgument bbArg : forOp.getRegionIterArgs()) {
|
|
unsigned idx = bbArg.getArgNumber() - /*numIv=*/1;
|
|
auto yieldOp = cast<scf::YieldOp>(forOp.region().front().getTerminator());
|
|
Value yieldVal = yieldOp->getOperand(idx);
|
|
auto tensorLoadOp = yieldVal.getDefiningOp<memref::TensorLoadOp>();
|
|
bool isTensor = bbArg.getType().isa<TensorType>();
|
|
|
|
memref::BufferCastOp bufferCastOp;
|
|
// Either bbArg has no use or it has a single buffer_cast use.
|
|
if (bbArg.hasOneUse())
|
|
bufferCastOp =
|
|
dyn_cast<memref::BufferCastOp>(*bbArg.getUsers().begin());
|
|
if (!isTensor || !tensorLoadOp || (!bbArg.use_empty() && !bufferCastOp))
|
|
continue;
|
|
// If bufferCastOp is present, it must feed into the `tensorLoadOp`.
|
|
if (bufferCastOp && tensorLoadOp.memref() != bufferCastOp)
|
|
continue;
|
|
// TODO: Any aliasing write of tensorLoadOp.memref() nested under `forOp`
|
|
// must be before `tensorLoadOp` in the block so that the lastWrite
|
|
// property is not subject to additional side-effects.
|
|
// For now, we only support the case when tensorLoadOp appears immediately
|
|
// before the terminator.
|
|
if (tensorLoadOp->getNextNode() != yieldOp)
|
|
continue;
|
|
|
|
// Clone the optional bufferCastOp before forOp.
|
|
if (bufferCastOp) {
|
|
rewriter.setInsertionPoint(forOp);
|
|
rewriter.replaceOpWithNewOp<memref::BufferCastOp>(
|
|
bufferCastOp, bufferCastOp.memref().getType(),
|
|
bufferCastOp.tensor());
|
|
}
|
|
|
|
// Clone the tensorLoad after forOp.
|
|
rewriter.setInsertionPointAfter(forOp);
|
|
Value newTensorLoad =
|
|
rewriter.create<memref::TensorLoadOp>(loc, tensorLoadOp.memref());
|
|
Value forOpResult = forOp.getResult(bbArg.getArgNumber() - /*iv=*/1);
|
|
replacements.insert(std::make_pair(forOpResult, newTensorLoad));
|
|
|
|
// Make the terminator just yield the bbArg, the old tensorLoadOp + the
|
|
// old bbArg (that is now directly yielded) will canonicalize away.
|
|
rewriter.startRootUpdate(yieldOp);
|
|
yieldOp.setOperand(idx, bbArg);
|
|
rewriter.finalizeRootUpdate(yieldOp);
|
|
}
|
|
if (replacements.empty())
|
|
return failure();
|
|
|
|
// We want to replace a subset of the results of `forOp`. rewriter.replaceOp
|
|
// replaces the whole op and erase it unconditionally. This is wrong for
|
|
// `forOp` as it generally contains ops with side effects.
|
|
// Instead, use `rewriter.replaceOpWithIf`.
|
|
SmallVector<Value> newResults;
|
|
newResults.reserve(forOp.getNumResults());
|
|
for (Value v : forOp.getResults()) {
|
|
auto it = replacements.find(v);
|
|
newResults.push_back((it != replacements.end()) ? it->second : v);
|
|
}
|
|
unsigned idx = 0;
|
|
rewriter.replaceOpWithIf(forOp, newResults, [&](OpOperand &op) {
|
|
return op.get() != newResults[idx++];
|
|
});
|
|
return success();
|
|
}
|
|
};
|
|
} // namespace
|
|
|
|
void ForOp::getCanonicalizationPatterns(RewritePatternSet &results,
|
|
MLIRContext *context) {
|
|
results.add<ForOpIterArgsFolder, SimplifyTrivialLoops,
|
|
LastTensorLoadCanonicalization, ForOpTensorCastFolder>(context);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// IfOp
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void IfOp::build(OpBuilder &builder, OperationState &result, Value cond,
|
|
bool withElseRegion) {
|
|
build(builder, result, /*resultTypes=*/llvm::None, cond, withElseRegion);
|
|
}
|
|
|
|
void IfOp::build(OpBuilder &builder, OperationState &result,
|
|
TypeRange resultTypes, Value cond, bool withElseRegion) {
|
|
auto addTerminator = [&](OpBuilder &nested, Location loc) {
|
|
if (resultTypes.empty())
|
|
IfOp::ensureTerminator(*nested.getInsertionBlock()->getParent(), nested,
|
|
loc);
|
|
};
|
|
|
|
build(builder, result, resultTypes, cond, addTerminator,
|
|
withElseRegion ? addTerminator
|
|
: function_ref<void(OpBuilder &, Location)>());
|
|
}
|
|
|
|
void IfOp::build(OpBuilder &builder, OperationState &result,
|
|
TypeRange resultTypes, Value cond,
|
|
function_ref<void(OpBuilder &, Location)> thenBuilder,
|
|
function_ref<void(OpBuilder &, Location)> elseBuilder) {
|
|
assert(thenBuilder && "the builder callback for 'then' must be present");
|
|
|
|
result.addOperands(cond);
|
|
result.addTypes(resultTypes);
|
|
|
|
OpBuilder::InsertionGuard guard(builder);
|
|
Region *thenRegion = result.addRegion();
|
|
builder.createBlock(thenRegion);
|
|
thenBuilder(builder, result.location);
|
|
|
|
Region *elseRegion = result.addRegion();
|
|
if (!elseBuilder)
|
|
return;
|
|
|
|
builder.createBlock(elseRegion);
|
|
elseBuilder(builder, result.location);
|
|
}
|
|
|
|
void IfOp::build(OpBuilder &builder, OperationState &result, Value cond,
|
|
function_ref<void(OpBuilder &, Location)> thenBuilder,
|
|
function_ref<void(OpBuilder &, Location)> elseBuilder) {
|
|
build(builder, result, TypeRange(), cond, thenBuilder, elseBuilder);
|
|
}
|
|
|
|
static LogicalResult verify(IfOp op) {
|
|
if (op.getNumResults() != 0 && op.elseRegion().empty())
|
|
return op.emitOpError("must have an else block if defining values");
|
|
|
|
return RegionBranchOpInterface::verifyTypes(op);
|
|
}
|
|
|
|
static ParseResult parseIfOp(OpAsmParser &parser, OperationState &result) {
|
|
// Create the regions for 'then'.
|
|
result.regions.reserve(2);
|
|
Region *thenRegion = result.addRegion();
|
|
Region *elseRegion = result.addRegion();
|
|
|
|
auto &builder = parser.getBuilder();
|
|
OpAsmParser::OperandType cond;
|
|
Type i1Type = builder.getIntegerType(1);
|
|
if (parser.parseOperand(cond) ||
|
|
parser.resolveOperand(cond, i1Type, result.operands))
|
|
return failure();
|
|
// Parse optional results type list.
|
|
if (parser.parseOptionalArrowTypeList(result.types))
|
|
return failure();
|
|
// Parse the 'then' region.
|
|
if (parser.parseRegion(*thenRegion, /*arguments=*/{}, /*argTypes=*/{}))
|
|
return failure();
|
|
IfOp::ensureTerminator(*thenRegion, parser.getBuilder(), result.location);
|
|
|
|
// If we find an 'else' keyword then parse the 'else' region.
|
|
if (!parser.parseOptionalKeyword("else")) {
|
|
if (parser.parseRegion(*elseRegion, /*arguments=*/{}, /*argTypes=*/{}))
|
|
return failure();
|
|
IfOp::ensureTerminator(*elseRegion, parser.getBuilder(), result.location);
|
|
}
|
|
|
|
// Parse the optional attribute list.
|
|
if (parser.parseOptionalAttrDict(result.attributes))
|
|
return failure();
|
|
return success();
|
|
}
|
|
|
|
static void print(OpAsmPrinter &p, IfOp op) {
|
|
bool printBlockTerminators = false;
|
|
|
|
p << " " << op.condition();
|
|
if (!op.results().empty()) {
|
|
p << " -> (" << op.getResultTypes() << ")";
|
|
// Print yield explicitly if the op defines values.
|
|
printBlockTerminators = true;
|
|
}
|
|
p.printRegion(op.thenRegion(),
|
|
/*printEntryBlockArgs=*/false,
|
|
/*printBlockTerminators=*/printBlockTerminators);
|
|
|
|
// Print the 'else' regions if it exists and has a block.
|
|
auto &elseRegion = op.elseRegion();
|
|
if (!elseRegion.empty()) {
|
|
p << " else";
|
|
p.printRegion(elseRegion,
|
|
/*printEntryBlockArgs=*/false,
|
|
/*printBlockTerminators=*/printBlockTerminators);
|
|
}
|
|
|
|
p.printOptionalAttrDict(op->getAttrs());
|
|
}
|
|
|
|
/// Given the region at `index`, or the parent operation if `index` is None,
|
|
/// return the successor regions. These are the regions that may be selected
|
|
/// during the flow of control. `operands` is a set of optional attributes that
|
|
/// correspond to a constant value for each operand, or null if that operand is
|
|
/// not a constant.
|
|
void IfOp::getSuccessorRegions(Optional<unsigned> index,
|
|
ArrayRef<Attribute> operands,
|
|
SmallVectorImpl<RegionSuccessor> ®ions) {
|
|
// The `then` and the `else` region branch back to the parent operation.
|
|
if (index.hasValue()) {
|
|
regions.push_back(RegionSuccessor(getResults()));
|
|
return;
|
|
}
|
|
|
|
// Don't consider the else region if it is empty.
|
|
Region *elseRegion = &this->elseRegion();
|
|
if (elseRegion->empty())
|
|
elseRegion = nullptr;
|
|
|
|
// Otherwise, the successor is dependent on the condition.
|
|
bool condition;
|
|
if (auto condAttr = operands.front().dyn_cast_or_null<IntegerAttr>()) {
|
|
condition = condAttr.getValue().isOneValue();
|
|
} else {
|
|
// If the condition isn't constant, both regions may be executed.
|
|
regions.push_back(RegionSuccessor(&thenRegion()));
|
|
// If the else region does not exist, it is not a viable successor.
|
|
if (elseRegion)
|
|
regions.push_back(RegionSuccessor(elseRegion));
|
|
return;
|
|
}
|
|
|
|
// Add the successor regions using the condition.
|
|
regions.push_back(RegionSuccessor(condition ? &thenRegion() : elseRegion));
|
|
}
|
|
|
|
namespace {
|
|
// Pattern to remove unused IfOp results.
|
|
struct RemoveUnusedResults : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
void transferBody(Block *source, Block *dest, ArrayRef<OpResult> usedResults,
|
|
PatternRewriter &rewriter) const {
|
|
// Move all operations to the destination block.
|
|
rewriter.mergeBlocks(source, dest);
|
|
// Replace the yield op by one that returns only the used values.
|
|
auto yieldOp = cast<scf::YieldOp>(dest->getTerminator());
|
|
SmallVector<Value, 4> usedOperands;
|
|
llvm::transform(usedResults, std::back_inserter(usedOperands),
|
|
[&](OpResult result) {
|
|
return yieldOp.getOperand(result.getResultNumber());
|
|
});
|
|
rewriter.updateRootInPlace(yieldOp,
|
|
[&]() { yieldOp->setOperands(usedOperands); });
|
|
}
|
|
|
|
LogicalResult matchAndRewrite(IfOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
// Compute the list of used results.
|
|
SmallVector<OpResult, 4> usedResults;
|
|
llvm::copy_if(op.getResults(), std::back_inserter(usedResults),
|
|
[](OpResult result) { return !result.use_empty(); });
|
|
|
|
// Replace the operation if only a subset of its results have uses.
|
|
if (usedResults.size() == op.getNumResults())
|
|
return failure();
|
|
|
|
// Compute the result types of the replacement operation.
|
|
SmallVector<Type, 4> newTypes;
|
|
llvm::transform(usedResults, std::back_inserter(newTypes),
|
|
[](OpResult result) { return result.getType(); });
|
|
|
|
// Create a replacement operation with empty then and else regions.
|
|
auto emptyBuilder = [](OpBuilder &, Location) {};
|
|
auto newOp = rewriter.create<IfOp>(op.getLoc(), newTypes, op.condition(),
|
|
emptyBuilder, emptyBuilder);
|
|
|
|
// Move the bodies and replace the terminators (note there is a then and
|
|
// an else region since the operation returns results).
|
|
transferBody(op.getBody(0), newOp.getBody(0), usedResults, rewriter);
|
|
transferBody(op.getBody(1), newOp.getBody(1), usedResults, rewriter);
|
|
|
|
// Replace the operation by the new one.
|
|
SmallVector<Value, 4> repResults(op.getNumResults());
|
|
for (auto en : llvm::enumerate(usedResults))
|
|
repResults[en.value().getResultNumber()] = newOp.getResult(en.index());
|
|
rewriter.replaceOp(op, repResults);
|
|
return success();
|
|
}
|
|
};
|
|
|
|
struct RemoveStaticCondition : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(IfOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
auto constant = op.condition().getDefiningOp<ConstantOp>();
|
|
if (!constant)
|
|
return failure();
|
|
|
|
if (constant.getValue().cast<BoolAttr>().getValue())
|
|
replaceOpWithRegion(rewriter, op, op.thenRegion());
|
|
else if (!op.elseRegion().empty())
|
|
replaceOpWithRegion(rewriter, op, op.elseRegion());
|
|
else
|
|
rewriter.eraseOp(op);
|
|
|
|
return success();
|
|
}
|
|
};
|
|
|
|
struct ConvertTrivialIfToSelect : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(IfOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
if (op->getNumResults() == 0)
|
|
return failure();
|
|
|
|
if (!llvm::hasSingleElement(op.thenRegion().front()) ||
|
|
!llvm::hasSingleElement(op.elseRegion().front()))
|
|
return failure();
|
|
|
|
auto cond = op.condition();
|
|
auto thenYieldArgs =
|
|
cast<scf::YieldOp>(op.thenRegion().front().getTerminator())
|
|
.getOperands();
|
|
auto elseYieldArgs =
|
|
cast<scf::YieldOp>(op.elseRegion().front().getTerminator())
|
|
.getOperands();
|
|
SmallVector<Value> results(op->getNumResults());
|
|
assert(thenYieldArgs.size() == results.size());
|
|
assert(elseYieldArgs.size() == results.size());
|
|
for (auto it : llvm::enumerate(llvm::zip(thenYieldArgs, elseYieldArgs))) {
|
|
Value trueVal = std::get<0>(it.value());
|
|
Value falseVal = std::get<1>(it.value());
|
|
if (trueVal == falseVal)
|
|
results[it.index()] = trueVal;
|
|
else
|
|
results[it.index()] =
|
|
rewriter.create<SelectOp>(op.getLoc(), cond, trueVal, falseVal);
|
|
}
|
|
|
|
rewriter.replaceOp(op, results);
|
|
return success();
|
|
}
|
|
};
|
|
|
|
/// Allow the true region of an if to assume the condition is true
|
|
/// and vice versa. For example:
|
|
///
|
|
/// scf.if %cmp {
|
|
/// print(%cmp)
|
|
/// }
|
|
///
|
|
/// becomes
|
|
///
|
|
/// scf.if %cmp {
|
|
/// print(true)
|
|
/// }
|
|
///
|
|
struct ConditionPropagation : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(IfOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
// Early exit if the condition is constant since replacing a constant
|
|
// in the body with another constant isn't a simplification.
|
|
if (op.condition().getDefiningOp<ConstantOp>())
|
|
return failure();
|
|
|
|
bool changed = false;
|
|
mlir::Type i1Ty = rewriter.getI1Type();
|
|
|
|
// These variables serve to prevent creating duplicate constants
|
|
// and hold constant true or false values.
|
|
Value constantTrue = nullptr;
|
|
Value constantFalse = nullptr;
|
|
|
|
for (OpOperand &use :
|
|
llvm::make_early_inc_range(op.condition().getUses())) {
|
|
if (op.thenRegion().isAncestor(use.getOwner()->getParentRegion())) {
|
|
changed = true;
|
|
|
|
if (!constantTrue)
|
|
constantTrue = rewriter.create<mlir::ConstantOp>(
|
|
op.getLoc(), i1Ty, rewriter.getIntegerAttr(i1Ty, 1));
|
|
|
|
rewriter.updateRootInPlace(use.getOwner(),
|
|
[&]() { use.set(constantTrue); });
|
|
} else if (op.elseRegion().isAncestor(
|
|
use.getOwner()->getParentRegion())) {
|
|
changed = true;
|
|
|
|
if (!constantFalse)
|
|
constantFalse = rewriter.create<mlir::ConstantOp>(
|
|
op.getLoc(), i1Ty, rewriter.getIntegerAttr(i1Ty, 0));
|
|
|
|
rewriter.updateRootInPlace(use.getOwner(),
|
|
[&]() { use.set(constantFalse); });
|
|
}
|
|
}
|
|
|
|
return success(changed);
|
|
}
|
|
};
|
|
|
|
/// Remove any statements from an if that are equivalent to the condition
|
|
/// or its negation. For example:
|
|
///
|
|
/// %res:2 = scf.if %cmp {
|
|
/// yield something(), true
|
|
/// } else {
|
|
/// yield something2(), false
|
|
/// }
|
|
/// print(%res#1)
|
|
///
|
|
/// becomes
|
|
/// %res = scf.if %cmp {
|
|
/// yield something()
|
|
/// } else {
|
|
/// yield something2()
|
|
/// }
|
|
/// print(%cmp)
|
|
///
|
|
/// Additionally if both branches yield the same value, replace all uses
|
|
/// of the result with the yielded value.
|
|
///
|
|
/// %res:2 = scf.if %cmp {
|
|
/// yield something(), %arg1
|
|
/// } else {
|
|
/// yield something2(), %arg1
|
|
/// }
|
|
/// print(%res#1)
|
|
///
|
|
/// becomes
|
|
/// %res = scf.if %cmp {
|
|
/// yield something()
|
|
/// } else {
|
|
/// yield something2()
|
|
/// }
|
|
/// print(%arg1)
|
|
///
|
|
struct ReplaceIfYieldWithConditionOrValue : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(IfOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
// Early exit if there are no results that could be replaced.
|
|
if (op.getNumResults() == 0)
|
|
return failure();
|
|
|
|
auto trueYield = cast<scf::YieldOp>(op.thenRegion().back().getTerminator());
|
|
auto falseYield =
|
|
cast<scf::YieldOp>(op.elseRegion().back().getTerminator());
|
|
|
|
rewriter.setInsertionPoint(op->getBlock(),
|
|
op.getOperation()->getIterator());
|
|
bool changed = false;
|
|
Type i1Ty = rewriter.getI1Type();
|
|
for (auto tup :
|
|
llvm::zip(trueYield.results(), falseYield.results(), op.results())) {
|
|
Value trueResult, falseResult, opResult;
|
|
std::tie(trueResult, falseResult, opResult) = tup;
|
|
|
|
if (trueResult == falseResult) {
|
|
if (!opResult.use_empty()) {
|
|
opResult.replaceAllUsesWith(trueResult);
|
|
changed = true;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
auto trueYield = trueResult.getDefiningOp<ConstantOp>();
|
|
if (!trueYield)
|
|
continue;
|
|
|
|
if (!trueYield.getType().isInteger(1))
|
|
continue;
|
|
|
|
auto falseYield = falseResult.getDefiningOp<ConstantOp>();
|
|
if (!falseYield)
|
|
continue;
|
|
|
|
bool trueVal = trueYield.getValue().cast<BoolAttr>().getValue();
|
|
bool falseVal = falseYield.getValue().cast<BoolAttr>().getValue();
|
|
if (!trueVal && falseVal) {
|
|
if (!opResult.use_empty()) {
|
|
Value notCond = rewriter.create<XOrOp>(
|
|
op.getLoc(), op.condition(),
|
|
rewriter.create<mlir::ConstantOp>(
|
|
op.getLoc(), i1Ty, rewriter.getIntegerAttr(i1Ty, 1)));
|
|
opResult.replaceAllUsesWith(notCond);
|
|
changed = true;
|
|
}
|
|
}
|
|
if (trueVal && !falseVal) {
|
|
if (!opResult.use_empty()) {
|
|
opResult.replaceAllUsesWith(op.condition());
|
|
changed = true;
|
|
}
|
|
}
|
|
}
|
|
return success(changed);
|
|
}
|
|
};
|
|
|
|
/// Merge any consecutive scf.if's with the same condition.
|
|
///
|
|
/// scf.if %cond {
|
|
/// firstCodeTrue();...
|
|
/// } else {
|
|
/// firstCodeFalse();...
|
|
/// }
|
|
/// %res = scf.if %cond {
|
|
/// secondCodeTrue();...
|
|
/// } else {
|
|
/// secondCodeFalse();...
|
|
/// }
|
|
///
|
|
/// becomes
|
|
/// %res = scf.if %cmp {
|
|
/// firstCodeTrue();...
|
|
/// secondCodeTrue();...
|
|
/// } else {
|
|
/// firstCodeFalse();...
|
|
/// secondCodeFalse();...
|
|
/// }
|
|
struct CombineIfs : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(IfOp nextIf,
|
|
PatternRewriter &rewriter) const override {
|
|
Block *parent = nextIf->getBlock();
|
|
if (nextIf == &parent->front())
|
|
return failure();
|
|
|
|
auto prevIf = dyn_cast<IfOp>(nextIf->getPrevNode());
|
|
if (!prevIf)
|
|
return failure();
|
|
|
|
if (nextIf.condition() != prevIf.condition())
|
|
return failure();
|
|
|
|
// Don't permit merging if a result of the first if is used
|
|
// within the second.
|
|
if (llvm::any_of(prevIf->getUsers(),
|
|
[&](Operation *user) { return nextIf->isAncestor(user); }))
|
|
return failure();
|
|
|
|
SmallVector<Type> mergedTypes(prevIf.getResultTypes());
|
|
llvm::append_range(mergedTypes, nextIf.getResultTypes());
|
|
|
|
IfOp combinedIf = rewriter.create<IfOp>(
|
|
nextIf.getLoc(), mergedTypes, nextIf.condition(), /*hasElse=*/false);
|
|
rewriter.eraseBlock(&combinedIf.thenRegion().back());
|
|
|
|
YieldOp thenYield = prevIf.thenYield();
|
|
YieldOp thenYield2 = nextIf.thenYield();
|
|
|
|
combinedIf.thenRegion().getBlocks().splice(
|
|
combinedIf.thenRegion().getBlocks().begin(),
|
|
prevIf.thenRegion().getBlocks());
|
|
|
|
rewriter.mergeBlocks(nextIf.thenBlock(), combinedIf.thenBlock());
|
|
rewriter.setInsertionPointToEnd(combinedIf.thenBlock());
|
|
|
|
SmallVector<Value> mergedYields(thenYield.getOperands());
|
|
llvm::append_range(mergedYields, thenYield2.getOperands());
|
|
rewriter.create<YieldOp>(thenYield2.getLoc(), mergedYields);
|
|
rewriter.eraseOp(thenYield);
|
|
rewriter.eraseOp(thenYield2);
|
|
|
|
combinedIf.elseRegion().getBlocks().splice(
|
|
combinedIf.elseRegion().getBlocks().begin(),
|
|
prevIf.elseRegion().getBlocks());
|
|
|
|
if (!nextIf.elseRegion().empty()) {
|
|
if (combinedIf.elseRegion().empty()) {
|
|
combinedIf.elseRegion().getBlocks().splice(
|
|
combinedIf.elseRegion().getBlocks().begin(),
|
|
nextIf.elseRegion().getBlocks());
|
|
} else {
|
|
YieldOp elseYield = combinedIf.elseYield();
|
|
YieldOp elseYield2 = nextIf.elseYield();
|
|
rewriter.mergeBlocks(nextIf.elseBlock(), combinedIf.elseBlock());
|
|
|
|
rewriter.setInsertionPointToEnd(combinedIf.elseBlock());
|
|
|
|
SmallVector<Value> mergedElseYields(elseYield.getOperands());
|
|
llvm::append_range(mergedElseYields, elseYield2.getOperands());
|
|
|
|
rewriter.create<YieldOp>(elseYield2.getLoc(), mergedElseYields);
|
|
rewriter.eraseOp(elseYield);
|
|
rewriter.eraseOp(elseYield2);
|
|
}
|
|
}
|
|
|
|
SmallVector<Value> prevValues;
|
|
SmallVector<Value> nextValues;
|
|
for (auto pair : llvm::enumerate(combinedIf.getResults())) {
|
|
if (pair.index() < prevIf.getNumResults())
|
|
prevValues.push_back(pair.value());
|
|
else
|
|
nextValues.push_back(pair.value());
|
|
}
|
|
rewriter.replaceOp(prevIf, prevValues);
|
|
rewriter.replaceOp(nextIf, nextValues);
|
|
return success();
|
|
}
|
|
};
|
|
|
|
/// Pattern to remove an empty else branch.
|
|
struct RemoveEmptyElseBranch : public OpRewritePattern<IfOp> {
|
|
using OpRewritePattern<IfOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(IfOp ifOp,
|
|
PatternRewriter &rewriter) const override {
|
|
// Cannot remove else region when there are operation results.
|
|
if (ifOp.getNumResults())
|
|
return failure();
|
|
Block *elseBlock = ifOp.elseBlock();
|
|
if (!elseBlock || !llvm::hasSingleElement(*elseBlock))
|
|
return failure();
|
|
auto newIfOp = rewriter.cloneWithoutRegions(ifOp);
|
|
rewriter.inlineRegionBefore(ifOp.thenRegion(), newIfOp.thenRegion(),
|
|
newIfOp.thenRegion().begin());
|
|
rewriter.eraseOp(ifOp);
|
|
return success();
|
|
}
|
|
};
|
|
|
|
} // namespace
|
|
|
|
void IfOp::getCanonicalizationPatterns(RewritePatternSet &results,
|
|
MLIRContext *context) {
|
|
results
|
|
.add<RemoveUnusedResults, RemoveStaticCondition, ConvertTrivialIfToSelect,
|
|
ConditionPropagation, ReplaceIfYieldWithConditionOrValue, CombineIfs,
|
|
RemoveEmptyElseBranch>(context);
|
|
}
|
|
|
|
Block *IfOp::thenBlock() { return &thenRegion().back(); }
|
|
YieldOp IfOp::thenYield() { return cast<YieldOp>(&thenBlock()->back()); }
|
|
Block *IfOp::elseBlock() {
|
|
Region &r = elseRegion();
|
|
if (r.empty())
|
|
return nullptr;
|
|
return &r.back();
|
|
}
|
|
YieldOp IfOp::elseYield() { return cast<YieldOp>(&elseBlock()->back()); }
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ParallelOp
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void ParallelOp::build(
|
|
OpBuilder &builder, OperationState &result, ValueRange lowerBounds,
|
|
ValueRange upperBounds, ValueRange steps, ValueRange initVals,
|
|
function_ref<void(OpBuilder &, Location, ValueRange, ValueRange)>
|
|
bodyBuilderFn) {
|
|
result.addOperands(lowerBounds);
|
|
result.addOperands(upperBounds);
|
|
result.addOperands(steps);
|
|
result.addOperands(initVals);
|
|
result.addAttribute(
|
|
ParallelOp::getOperandSegmentSizeAttr(),
|
|
builder.getI32VectorAttr({static_cast<int32_t>(lowerBounds.size()),
|
|
static_cast<int32_t>(upperBounds.size()),
|
|
static_cast<int32_t>(steps.size()),
|
|
static_cast<int32_t>(initVals.size())}));
|
|
result.addTypes(initVals.getTypes());
|
|
|
|
OpBuilder::InsertionGuard guard(builder);
|
|
unsigned numIVs = steps.size();
|
|
SmallVector<Type, 8> argTypes(numIVs, builder.getIndexType());
|
|
Region *bodyRegion = result.addRegion();
|
|
Block *bodyBlock = builder.createBlock(bodyRegion, {}, argTypes);
|
|
|
|
if (bodyBuilderFn) {
|
|
builder.setInsertionPointToStart(bodyBlock);
|
|
bodyBuilderFn(builder, result.location,
|
|
bodyBlock->getArguments().take_front(numIVs),
|
|
bodyBlock->getArguments().drop_front(numIVs));
|
|
}
|
|
ParallelOp::ensureTerminator(*bodyRegion, builder, result.location);
|
|
}
|
|
|
|
void ParallelOp::build(
|
|
OpBuilder &builder, OperationState &result, ValueRange lowerBounds,
|
|
ValueRange upperBounds, ValueRange steps,
|
|
function_ref<void(OpBuilder &, Location, ValueRange)> bodyBuilderFn) {
|
|
// Only pass a non-null wrapper if bodyBuilderFn is non-null itself. Make sure
|
|
// we don't capture a reference to a temporary by constructing the lambda at
|
|
// function level.
|
|
auto wrappedBuilderFn = [&bodyBuilderFn](OpBuilder &nestedBuilder,
|
|
Location nestedLoc, ValueRange ivs,
|
|
ValueRange) {
|
|
bodyBuilderFn(nestedBuilder, nestedLoc, ivs);
|
|
};
|
|
function_ref<void(OpBuilder &, Location, ValueRange, ValueRange)> wrapper;
|
|
if (bodyBuilderFn)
|
|
wrapper = wrappedBuilderFn;
|
|
|
|
build(builder, result, lowerBounds, upperBounds, steps, ValueRange(),
|
|
wrapper);
|
|
}
|
|
|
|
static LogicalResult verify(ParallelOp op) {
|
|
// Check that there is at least one value in lowerBound, upperBound and step.
|
|
// It is sufficient to test only step, because it is ensured already that the
|
|
// number of elements in lowerBound, upperBound and step are the same.
|
|
Operation::operand_range stepValues = op.step();
|
|
if (stepValues.empty())
|
|
return op.emitOpError(
|
|
"needs at least one tuple element for lowerBound, upperBound and step");
|
|
|
|
// Check whether all constant step values are positive.
|
|
for (Value stepValue : stepValues)
|
|
if (auto cst = stepValue.getDefiningOp<ConstantIndexOp>())
|
|
if (cst.getValue() <= 0)
|
|
return op.emitOpError("constant step operand must be positive");
|
|
|
|
// Check that the body defines the same number of block arguments as the
|
|
// number of tuple elements in step.
|
|
Block *body = op.getBody();
|
|
if (body->getNumArguments() != stepValues.size())
|
|
return op.emitOpError()
|
|
<< "expects the same number of induction variables: "
|
|
<< body->getNumArguments()
|
|
<< " as bound and step values: " << stepValues.size();
|
|
for (auto arg : body->getArguments())
|
|
if (!arg.getType().isIndex())
|
|
return op.emitOpError(
|
|
"expects arguments for the induction variable to be of index type");
|
|
|
|
// Check that the yield has no results
|
|
Operation *yield = body->getTerminator();
|
|
if (yield->getNumOperands() != 0)
|
|
return yield->emitOpError() << "not allowed to have operands inside '"
|
|
<< ParallelOp::getOperationName() << "'";
|
|
|
|
// Check that the number of results is the same as the number of ReduceOps.
|
|
SmallVector<ReduceOp, 4> reductions(body->getOps<ReduceOp>());
|
|
auto resultsSize = op.results().size();
|
|
auto reductionsSize = reductions.size();
|
|
auto initValsSize = op.initVals().size();
|
|
if (resultsSize != reductionsSize)
|
|
return op.emitOpError()
|
|
<< "expects number of results: " << resultsSize
|
|
<< " to be the same as number of reductions: " << reductionsSize;
|
|
if (resultsSize != initValsSize)
|
|
return op.emitOpError()
|
|
<< "expects number of results: " << resultsSize
|
|
<< " to be the same as number of initial values: " << initValsSize;
|
|
|
|
// Check that the types of the results and reductions are the same.
|
|
for (auto resultAndReduce : llvm::zip(op.results(), reductions)) {
|
|
auto resultType = std::get<0>(resultAndReduce).getType();
|
|
auto reduceOp = std::get<1>(resultAndReduce);
|
|
auto reduceType = reduceOp.operand().getType();
|
|
if (resultType != reduceType)
|
|
return reduceOp.emitOpError()
|
|
<< "expects type of reduce: " << reduceType
|
|
<< " to be the same as result type: " << resultType;
|
|
}
|
|
return success();
|
|
}
|
|
|
|
static ParseResult parseParallelOp(OpAsmParser &parser,
|
|
OperationState &result) {
|
|
auto &builder = parser.getBuilder();
|
|
// Parse an opening `(` followed by induction variables followed by `)`
|
|
SmallVector<OpAsmParser::OperandType, 4> ivs;
|
|
if (parser.parseRegionArgumentList(ivs, /*requiredOperandCount=*/-1,
|
|
OpAsmParser::Delimiter::Paren))
|
|
return failure();
|
|
|
|
// Parse loop bounds.
|
|
SmallVector<OpAsmParser::OperandType, 4> lower;
|
|
if (parser.parseEqual() ||
|
|
parser.parseOperandList(lower, ivs.size(),
|
|
OpAsmParser::Delimiter::Paren) ||
|
|
parser.resolveOperands(lower, builder.getIndexType(), result.operands))
|
|
return failure();
|
|
|
|
SmallVector<OpAsmParser::OperandType, 4> upper;
|
|
if (parser.parseKeyword("to") ||
|
|
parser.parseOperandList(upper, ivs.size(),
|
|
OpAsmParser::Delimiter::Paren) ||
|
|
parser.resolveOperands(upper, builder.getIndexType(), result.operands))
|
|
return failure();
|
|
|
|
// Parse step values.
|
|
SmallVector<OpAsmParser::OperandType, 4> steps;
|
|
if (parser.parseKeyword("step") ||
|
|
parser.parseOperandList(steps, ivs.size(),
|
|
OpAsmParser::Delimiter::Paren) ||
|
|
parser.resolveOperands(steps, builder.getIndexType(), result.operands))
|
|
return failure();
|
|
|
|
// Parse init values.
|
|
SmallVector<OpAsmParser::OperandType, 4> initVals;
|
|
if (succeeded(parser.parseOptionalKeyword("init"))) {
|
|
if (parser.parseOperandList(initVals, /*requiredOperandCount=*/-1,
|
|
OpAsmParser::Delimiter::Paren))
|
|
return failure();
|
|
}
|
|
|
|
// Parse optional results in case there is a reduce.
|
|
if (parser.parseOptionalArrowTypeList(result.types))
|
|
return failure();
|
|
|
|
// Now parse the body.
|
|
Region *body = result.addRegion();
|
|
SmallVector<Type, 4> types(ivs.size(), builder.getIndexType());
|
|
if (parser.parseRegion(*body, ivs, types))
|
|
return failure();
|
|
|
|
// Set `operand_segment_sizes` attribute.
|
|
result.addAttribute(
|
|
ParallelOp::getOperandSegmentSizeAttr(),
|
|
builder.getI32VectorAttr({static_cast<int32_t>(lower.size()),
|
|
static_cast<int32_t>(upper.size()),
|
|
static_cast<int32_t>(steps.size()),
|
|
static_cast<int32_t>(initVals.size())}));
|
|
|
|
// Parse attributes.
|
|
if (parser.parseOptionalAttrDict(result.attributes))
|
|
return failure();
|
|
|
|
if (!initVals.empty())
|
|
parser.resolveOperands(initVals, result.types, parser.getNameLoc(),
|
|
result.operands);
|
|
// Add a terminator if none was parsed.
|
|
ForOp::ensureTerminator(*body, builder, result.location);
|
|
|
|
return success();
|
|
}
|
|
|
|
static void print(OpAsmPrinter &p, ParallelOp op) {
|
|
p << " (" << op.getBody()->getArguments() << ") = (" << op.lowerBound()
|
|
<< ") to (" << op.upperBound() << ") step (" << op.step() << ")";
|
|
if (!op.initVals().empty())
|
|
p << " init (" << op.initVals() << ")";
|
|
p.printOptionalArrowTypeList(op.getResultTypes());
|
|
p.printRegion(op.region(), /*printEntryBlockArgs=*/false);
|
|
p.printOptionalAttrDict(
|
|
op->getAttrs(), /*elidedAttrs=*/ParallelOp::getOperandSegmentSizeAttr());
|
|
}
|
|
|
|
Region &ParallelOp::getLoopBody() { return region(); }
|
|
|
|
bool ParallelOp::isDefinedOutsideOfLoop(Value value) {
|
|
return !region().isAncestor(value.getParentRegion());
|
|
}
|
|
|
|
LogicalResult ParallelOp::moveOutOfLoop(ArrayRef<Operation *> ops) {
|
|
for (auto *op : ops)
|
|
op->moveBefore(*this);
|
|
return success();
|
|
}
|
|
|
|
ParallelOp mlir::scf::getParallelForInductionVarOwner(Value val) {
|
|
auto ivArg = val.dyn_cast<BlockArgument>();
|
|
if (!ivArg)
|
|
return ParallelOp();
|
|
assert(ivArg.getOwner() && "unlinked block argument");
|
|
auto *containingOp = ivArg.getOwner()->getParentOp();
|
|
return dyn_cast<ParallelOp>(containingOp);
|
|
}
|
|
|
|
namespace {
|
|
// Collapse loop dimensions that perform a single iteration.
|
|
struct CollapseSingleIterationLoops : public OpRewritePattern<ParallelOp> {
|
|
using OpRewritePattern<ParallelOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(ParallelOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
BlockAndValueMapping mapping;
|
|
// Compute new loop bounds that omit all single-iteration loop dimensions.
|
|
SmallVector<Value, 2> newLowerBounds;
|
|
SmallVector<Value, 2> newUpperBounds;
|
|
SmallVector<Value, 2> newSteps;
|
|
newLowerBounds.reserve(op.lowerBound().size());
|
|
newUpperBounds.reserve(op.upperBound().size());
|
|
newSteps.reserve(op.step().size());
|
|
for (auto dim : llvm::zip(op.lowerBound(), op.upperBound(), op.step(),
|
|
op.getInductionVars())) {
|
|
Value lowerBound, upperBound, step, iv;
|
|
std::tie(lowerBound, upperBound, step, iv) = dim;
|
|
// Collect the statically known loop bounds.
|
|
auto lowerBoundConstant =
|
|
dyn_cast_or_null<ConstantIndexOp>(lowerBound.getDefiningOp());
|
|
auto upperBoundConstant =
|
|
dyn_cast_or_null<ConstantIndexOp>(upperBound.getDefiningOp());
|
|
auto stepConstant =
|
|
dyn_cast_or_null<ConstantIndexOp>(step.getDefiningOp());
|
|
// Replace the loop induction variable by the lower bound if the loop
|
|
// performs a single iteration. Otherwise, copy the loop bounds.
|
|
if (lowerBoundConstant && upperBoundConstant && stepConstant &&
|
|
(upperBoundConstant.getValue() - lowerBoundConstant.getValue()) > 0 &&
|
|
(upperBoundConstant.getValue() - lowerBoundConstant.getValue()) <=
|
|
stepConstant.getValue()) {
|
|
mapping.map(iv, lowerBound);
|
|
} else {
|
|
newLowerBounds.push_back(lowerBound);
|
|
newUpperBounds.push_back(upperBound);
|
|
newSteps.push_back(step);
|
|
}
|
|
}
|
|
// Exit if none of the loop dimensions perform a single iteration.
|
|
if (newLowerBounds.size() == op.lowerBound().size())
|
|
return failure();
|
|
|
|
if (newLowerBounds.empty()) {
|
|
// All of the loop dimensions perform a single iteration. Inline
|
|
// loop body and nested ReduceOp's
|
|
SmallVector<Value> results;
|
|
results.reserve(op.initVals().size());
|
|
for (auto &bodyOp : op.getLoopBody().front().without_terminator()) {
|
|
auto reduce = dyn_cast<ReduceOp>(bodyOp);
|
|
if (!reduce) {
|
|
rewriter.clone(bodyOp, mapping);
|
|
continue;
|
|
}
|
|
Block &reduceBlock = reduce.reductionOperator().front();
|
|
auto initValIndex = results.size();
|
|
mapping.map(reduceBlock.getArgument(0), op.initVals()[initValIndex]);
|
|
mapping.map(reduceBlock.getArgument(1),
|
|
mapping.lookupOrDefault(reduce.operand()));
|
|
for (auto &reduceBodyOp : reduceBlock.without_terminator())
|
|
rewriter.clone(reduceBodyOp, mapping);
|
|
|
|
auto result = mapping.lookupOrDefault(
|
|
cast<ReduceReturnOp>(reduceBlock.getTerminator()).result());
|
|
results.push_back(result);
|
|
}
|
|
rewriter.replaceOp(op, results);
|
|
return success();
|
|
}
|
|
// Replace the parallel loop by lower-dimensional parallel loop.
|
|
auto newOp =
|
|
rewriter.create<ParallelOp>(op.getLoc(), newLowerBounds, newUpperBounds,
|
|
newSteps, op.initVals(), nullptr);
|
|
// Clone the loop body and remap the block arguments of the collapsed loops
|
|
// (inlining does not support a cancellable block argument mapping).
|
|
rewriter.cloneRegionBefore(op.region(), newOp.region(),
|
|
newOp.region().begin(), mapping);
|
|
rewriter.replaceOp(op, newOp.getResults());
|
|
return success();
|
|
}
|
|
};
|
|
|
|
/// Removes parallel loops in which at least one lower/upper bound pair consists
|
|
/// of the same values - such loops have an empty iteration domain.
|
|
struct RemoveEmptyParallelLoops : public OpRewritePattern<ParallelOp> {
|
|
using OpRewritePattern<ParallelOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(ParallelOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
for (auto dim : llvm::zip(op.lowerBound(), op.upperBound())) {
|
|
if (std::get<0>(dim) == std::get<1>(dim)) {
|
|
rewriter.replaceOp(op, op.initVals());
|
|
return success();
|
|
}
|
|
}
|
|
return failure();
|
|
}
|
|
};
|
|
|
|
struct MergeNestedParallelLoops : public OpRewritePattern<ParallelOp> {
|
|
using OpRewritePattern<ParallelOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(ParallelOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
Block &outerBody = op.getLoopBody().front();
|
|
if (!llvm::hasSingleElement(outerBody.without_terminator()))
|
|
return failure();
|
|
|
|
auto innerOp = dyn_cast<ParallelOp>(outerBody.front());
|
|
if (!innerOp)
|
|
return failure();
|
|
|
|
auto hasVal = [](const auto &range, Value val) {
|
|
return llvm::find(range, val) != range.end();
|
|
};
|
|
|
|
for (auto val : outerBody.getArguments())
|
|
if (hasVal(innerOp.lowerBound(), val) ||
|
|
hasVal(innerOp.upperBound(), val) || hasVal(innerOp.step(), val))
|
|
return failure();
|
|
|
|
// Reductions are not supported yet.
|
|
if (!op.initVals().empty() || !innerOp.initVals().empty())
|
|
return failure();
|
|
|
|
auto bodyBuilder = [&](OpBuilder &builder, Location /*loc*/,
|
|
ValueRange iterVals, ValueRange) {
|
|
Block &innerBody = innerOp.getLoopBody().front();
|
|
assert(iterVals.size() ==
|
|
(outerBody.getNumArguments() + innerBody.getNumArguments()));
|
|
BlockAndValueMapping mapping;
|
|
mapping.map(outerBody.getArguments(),
|
|
iterVals.take_front(outerBody.getNumArguments()));
|
|
mapping.map(innerBody.getArguments(),
|
|
iterVals.take_back(innerBody.getNumArguments()));
|
|
for (Operation &op : innerBody.without_terminator())
|
|
builder.clone(op, mapping);
|
|
};
|
|
|
|
auto concatValues = [](const auto &first, const auto &second) {
|
|
SmallVector<Value> ret;
|
|
ret.reserve(first.size() + second.size());
|
|
ret.assign(first.begin(), first.end());
|
|
ret.append(second.begin(), second.end());
|
|
return ret;
|
|
};
|
|
|
|
auto newLowerBounds = concatValues(op.lowerBound(), innerOp.lowerBound());
|
|
auto newUpperBounds = concatValues(op.upperBound(), innerOp.upperBound());
|
|
auto newSteps = concatValues(op.step(), innerOp.step());
|
|
|
|
rewriter.replaceOpWithNewOp<ParallelOp>(op, newLowerBounds, newUpperBounds,
|
|
newSteps, llvm::None, bodyBuilder);
|
|
return success();
|
|
}
|
|
};
|
|
|
|
} // namespace
|
|
|
|
void ParallelOp::getCanonicalizationPatterns(RewritePatternSet &results,
|
|
MLIRContext *context) {
|
|
results.add<CollapseSingleIterationLoops, RemoveEmptyParallelLoops,
|
|
MergeNestedParallelLoops>(context);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ReduceOp
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void ReduceOp::build(
|
|
OpBuilder &builder, OperationState &result, Value operand,
|
|
function_ref<void(OpBuilder &, Location, Value, Value)> bodyBuilderFn) {
|
|
auto type = operand.getType();
|
|
result.addOperands(operand);
|
|
|
|
OpBuilder::InsertionGuard guard(builder);
|
|
Region *bodyRegion = result.addRegion();
|
|
Block *body = builder.createBlock(bodyRegion, {}, ArrayRef<Type>{type, type});
|
|
if (bodyBuilderFn)
|
|
bodyBuilderFn(builder, result.location, body->getArgument(0),
|
|
body->getArgument(1));
|
|
}
|
|
|
|
static LogicalResult verify(ReduceOp op) {
|
|
// The region of a ReduceOp has two arguments of the same type as its operand.
|
|
auto type = op.operand().getType();
|
|
Block &block = op.reductionOperator().front();
|
|
if (block.empty())
|
|
return op.emitOpError("the block inside reduce should not be empty");
|
|
if (block.getNumArguments() != 2 ||
|
|
llvm::any_of(block.getArguments(), [&](const BlockArgument &arg) {
|
|
return arg.getType() != type;
|
|
}))
|
|
return op.emitOpError()
|
|
<< "expects two arguments to reduce block of type " << type;
|
|
|
|
// Check that the block is terminated by a ReduceReturnOp.
|
|
if (!isa<ReduceReturnOp>(block.getTerminator()))
|
|
return op.emitOpError("the block inside reduce should be terminated with a "
|
|
"'scf.reduce.return' op");
|
|
|
|
return success();
|
|
}
|
|
|
|
static ParseResult parseReduceOp(OpAsmParser &parser, OperationState &result) {
|
|
// Parse an opening `(` followed by the reduced value followed by `)`
|
|
OpAsmParser::OperandType operand;
|
|
if (parser.parseLParen() || parser.parseOperand(operand) ||
|
|
parser.parseRParen())
|
|
return failure();
|
|
|
|
Type resultType;
|
|
// Parse the type of the operand (and also what reduce computes on).
|
|
if (parser.parseColonType(resultType) ||
|
|
parser.resolveOperand(operand, resultType, result.operands))
|
|
return failure();
|
|
|
|
// Now parse the body.
|
|
Region *body = result.addRegion();
|
|
if (parser.parseRegion(*body, /*arguments=*/{}, /*argTypes=*/{}))
|
|
return failure();
|
|
|
|
return success();
|
|
}
|
|
|
|
static void print(OpAsmPrinter &p, ReduceOp op) {
|
|
p << "(" << op.operand() << ") ";
|
|
p << " : " << op.operand().getType();
|
|
p.printRegion(op.reductionOperator());
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ReduceReturnOp
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static LogicalResult verify(ReduceReturnOp op) {
|
|
// The type of the return value should be the same type as the type of the
|
|
// operand of the enclosing ReduceOp.
|
|
auto reduceOp = cast<ReduceOp>(op->getParentOp());
|
|
Type reduceType = reduceOp.operand().getType();
|
|
if (reduceType != op.result().getType())
|
|
return op.emitOpError() << "needs to have type " << reduceType
|
|
<< " (the type of the enclosing ReduceOp)";
|
|
return success();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// WhileOp
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
OperandRange WhileOp::getSuccessorEntryOperands(unsigned index) {
|
|
assert(index == 0 &&
|
|
"WhileOp is expected to branch only to the first region");
|
|
|
|
return inits();
|
|
}
|
|
|
|
ConditionOp WhileOp::getConditionOp() {
|
|
return cast<ConditionOp>(before().front().getTerminator());
|
|
}
|
|
|
|
Block::BlockArgListType WhileOp::getAfterArguments() {
|
|
return after().front().getArguments();
|
|
}
|
|
|
|
void WhileOp::getSuccessorRegions(Optional<unsigned> index,
|
|
ArrayRef<Attribute> operands,
|
|
SmallVectorImpl<RegionSuccessor> ®ions) {
|
|
(void)operands;
|
|
|
|
if (!index.hasValue()) {
|
|
regions.emplace_back(&before(), before().getArguments());
|
|
return;
|
|
}
|
|
|
|
assert(*index < 2 && "there are only two regions in a WhileOp");
|
|
if (*index == 0) {
|
|
regions.emplace_back(&after(), after().getArguments());
|
|
regions.emplace_back(getResults());
|
|
return;
|
|
}
|
|
|
|
regions.emplace_back(&before(), before().getArguments());
|
|
}
|
|
|
|
/// Parses a `while` op.
|
|
///
|
|
/// op ::= `scf.while` assignments `:` function-type region `do` region
|
|
/// `attributes` attribute-dict
|
|
/// initializer ::= /* empty */ | `(` assignment-list `)`
|
|
/// assignment-list ::= assignment | assignment `,` assignment-list
|
|
/// assignment ::= ssa-value `=` ssa-value
|
|
static ParseResult parseWhileOp(OpAsmParser &parser, OperationState &result) {
|
|
SmallVector<OpAsmParser::OperandType, 4> regionArgs, operands;
|
|
Region *before = result.addRegion();
|
|
Region *after = result.addRegion();
|
|
|
|
OptionalParseResult listResult =
|
|
parser.parseOptionalAssignmentList(regionArgs, operands);
|
|
if (listResult.hasValue() && failed(listResult.getValue()))
|
|
return failure();
|
|
|
|
FunctionType functionType;
|
|
llvm::SMLoc typeLoc = parser.getCurrentLocation();
|
|
if (failed(parser.parseColonType(functionType)))
|
|
return failure();
|
|
|
|
result.addTypes(functionType.getResults());
|
|
|
|
if (functionType.getNumInputs() != operands.size()) {
|
|
return parser.emitError(typeLoc)
|
|
<< "expected as many input types as operands "
|
|
<< "(expected " << operands.size() << " got "
|
|
<< functionType.getNumInputs() << ")";
|
|
}
|
|
|
|
// Resolve input operands.
|
|
if (failed(parser.resolveOperands(operands, functionType.getInputs(),
|
|
parser.getCurrentLocation(),
|
|
result.operands)))
|
|
return failure();
|
|
|
|
return failure(
|
|
parser.parseRegion(*before, regionArgs, functionType.getInputs()) ||
|
|
parser.parseKeyword("do") || parser.parseRegion(*after) ||
|
|
parser.parseOptionalAttrDictWithKeyword(result.attributes));
|
|
}
|
|
|
|
/// Prints a `while` op.
|
|
static void print(OpAsmPrinter &p, scf::WhileOp op) {
|
|
printInitializationList(p, op.before().front().getArguments(), op.inits(),
|
|
" ");
|
|
p << " : ";
|
|
p.printFunctionalType(op.inits().getTypes(), op.results().getTypes());
|
|
p.printRegion(op.before(), /*printEntryBlockArgs=*/false);
|
|
p << " do";
|
|
p.printRegion(op.after());
|
|
p.printOptionalAttrDictWithKeyword(op->getAttrs());
|
|
}
|
|
|
|
/// Verifies that two ranges of types match, i.e. have the same number of
|
|
/// entries and that types are pairwise equals. Reports errors on the given
|
|
/// operation in case of mismatch.
|
|
template <typename OpTy>
|
|
static LogicalResult verifyTypeRangesMatch(OpTy op, TypeRange left,
|
|
TypeRange right, StringRef message) {
|
|
if (left.size() != right.size())
|
|
return op.emitOpError("expects the same number of ") << message;
|
|
|
|
for (unsigned i = 0, e = left.size(); i < e; ++i) {
|
|
if (left[i] != right[i]) {
|
|
InFlightDiagnostic diag = op.emitOpError("expects the same types for ")
|
|
<< message;
|
|
diag.attachNote() << "for argument " << i << ", found " << left[i]
|
|
<< " and " << right[i];
|
|
return diag;
|
|
}
|
|
}
|
|
|
|
return success();
|
|
}
|
|
|
|
/// Verifies that the first block of the given `region` is terminated by a
|
|
/// YieldOp. Reports errors on the given operation if it is not the case.
|
|
template <typename TerminatorTy>
|
|
static TerminatorTy verifyAndGetTerminator(scf::WhileOp op, Region ®ion,
|
|
StringRef errorMessage) {
|
|
Operation *terminatorOperation = region.front().getTerminator();
|
|
if (auto yield = dyn_cast_or_null<TerminatorTy>(terminatorOperation))
|
|
return yield;
|
|
|
|
auto diag = op.emitOpError(errorMessage);
|
|
if (terminatorOperation)
|
|
diag.attachNote(terminatorOperation->getLoc()) << "terminator here";
|
|
return nullptr;
|
|
}
|
|
|
|
static LogicalResult verify(scf::WhileOp op) {
|
|
if (failed(RegionBranchOpInterface::verifyTypes(op)))
|
|
return failure();
|
|
|
|
auto beforeTerminator = verifyAndGetTerminator<scf::ConditionOp>(
|
|
op, op.before(),
|
|
"expects the 'before' region to terminate with 'scf.condition'");
|
|
if (!beforeTerminator)
|
|
return failure();
|
|
|
|
auto afterTerminator = verifyAndGetTerminator<scf::YieldOp>(
|
|
op, op.after(),
|
|
"expects the 'after' region to terminate with 'scf.yield'");
|
|
return success(afterTerminator != nullptr);
|
|
}
|
|
|
|
namespace {
|
|
/// Replace uses of the condition within the do block with true, since otherwise
|
|
/// the block would not be evaluated.
|
|
///
|
|
/// scf.while (..) : (i1, ...) -> ... {
|
|
/// %condition = call @evaluate_condition() : () -> i1
|
|
/// scf.condition(%condition) %condition : i1, ...
|
|
/// } do {
|
|
/// ^bb0(%arg0: i1, ...):
|
|
/// use(%arg0)
|
|
/// ...
|
|
///
|
|
/// becomes
|
|
/// scf.while (..) : (i1, ...) -> ... {
|
|
/// %condition = call @evaluate_condition() : () -> i1
|
|
/// scf.condition(%condition) %condition : i1, ...
|
|
/// } do {
|
|
/// ^bb0(%arg0: i1, ...):
|
|
/// use(%true)
|
|
/// ...
|
|
struct WhileConditionTruth : public OpRewritePattern<WhileOp> {
|
|
using OpRewritePattern<WhileOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(WhileOp op,
|
|
PatternRewriter &rewriter) const override {
|
|
auto term = op.getConditionOp();
|
|
|
|
// These variables serve to prevent creating duplicate constants
|
|
// and hold constant true or false values.
|
|
Value constantTrue = nullptr;
|
|
|
|
bool replaced = false;
|
|
for (auto yieldedAndBlockArgs :
|
|
llvm::zip(term.args(), op.getAfterArguments())) {
|
|
if (std::get<0>(yieldedAndBlockArgs) == term.condition()) {
|
|
if (!std::get<1>(yieldedAndBlockArgs).use_empty()) {
|
|
if (!constantTrue)
|
|
constantTrue = rewriter.create<mlir::ConstantOp>(
|
|
op.getLoc(), term.condition().getType(),
|
|
rewriter.getBoolAttr(true));
|
|
|
|
std::get<1>(yieldedAndBlockArgs).replaceAllUsesWith(constantTrue);
|
|
replaced = true;
|
|
}
|
|
}
|
|
}
|
|
return success(replaced);
|
|
}
|
|
};
|
|
} // namespace
|
|
|
|
void WhileOp::getCanonicalizationPatterns(OwningRewritePatternList &results,
|
|
MLIRContext *context) {
|
|
results.insert<WhileConditionTruth>(context);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// TableGen'd op method definitions
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#define GET_OP_CLASSES
|
|
#include "mlir/Dialect/SCF/SCFOps.cpp.inc"
|