/*! * Copyright (c) 2017 by Contributors * \file message_passing.cc * \brief The message passing domain. */ #include <tvm/arithmetic.h> #include <tvm/ir.h> #include <tvm/ir_pass.h> #include "./message_passing.h" #include "../arithmetic/compute_expr.h" namespace tvm { namespace schedule { using namespace ir; using namespace arith; // result = ceil((a / b)), both a and b are positive integer inline Expr DivCeil(Expr a, Expr b) { return ir::Simplify((a + b - 1) / b); } inline bool prove_equal(Expr lhs, Expr rhs) { return is_zero(ir::Simplify(lhs - rhs)); } void Update(std::unordered_map<IterVar, Range>* p_state, const IterVar& iv, Range r) { auto it = p_state->find(iv); if (it == p_state->end()) { (*p_state)[iv] = r; } else { bool match = is_zero(it->second->min); if (!prove_equal(r->extent, it->second->extent)) match = false; CHECK(match) << iv << " domain already inferred," << " cannot prove their extents are the same " << it->second->extent << " vs " << r->extent; } } void PassDownDomain(const Stage& stage, std::unordered_map<IterVar, Range>* p_state, bool allow_missing) { auto& state = *p_state; // forwar iteration on relations for (IterVarRelation rel : stage->relations) { if (const SplitNode* r = rel.as<SplitNode>()) { if (!state.count(r->parent)) { CHECK(allow_missing); continue; } CHECK(!state.count(r->inner)); const Range& range_parent = state.at(r->parent); if (r->factor.defined()) { Update(p_state, r->inner, Range::make_by_min_extent(0, r->factor)); Update(p_state, r->outer, Range::make_by_min_extent( 0, DivCeil(range_parent->extent, r->factor))); } else { Update(p_state, r->outer, Range::make_by_min_extent(0, r->nparts)); Update(p_state, r->inner, Range::make_by_min_extent( 0, DivCeil(range_parent->extent, r->nparts))); } } else if (const FuseNode* r = rel.as<FuseNode>()) { if (!state.count(r->outer) || !state.count(r->inner)) { CHECK(allow_missing); continue; } const Range& range_outer = state.at(r->outer); const Range& range_inner = state.at(r->inner); state[r->fused] = Range::make_by_min_extent( 0, range_outer->extent * range_inner->extent); } else if (const RebaseNode* r = rel.as<RebaseNode>()) { if (!state.count(r->parent)) { CHECK(allow_missing); continue; } Update(p_state, r->rebased, Range::make_by_min_extent( 0, state.at(r->parent)->extent)); } else { LOG(FATAL) << "unknown relation type"; } } // update the extents of binded threads. for (auto kv : stage->iter_var_attrs) { if (kv.second->bind_thread.defined()) { CHECK(state.count(kv.first)); Update(p_state, kv.second->bind_thread, state.at(kv.first)); } } } void PassUpIndex(const Stage& stage, const Map<IterVar, Range>& dom_map, std::unordered_map<IterVar, Expr>* p_state, bool allow_missing) { auto& state = *p_state; for (size_t i = stage->relations.size(); i != 0; --i) { IterVarRelation rel = stage->relations[i - 1]; if (const SplitNode* s = rel.as<SplitNode>()) { if (!state.count(s->outer) || !state.count(s->inner)) { CHECK(allow_missing); continue; } Expr outer = state.at(s->outer); Expr inner = state.at(s->inner); Expr factor = dom_map.at(s->inner)->extent; Expr parent_min = dom_map.at(s->parent)->min; state[s->parent] = inner + outer * factor; // add min if they exist if (!is_zero(parent_min)) { state[s->parent] = state[s->parent] + parent_min; } } else if (const FuseNode* s = rel.as<FuseNode>()) { if (!state.count(s->fused)) { CHECK(allow_missing); continue; } Expr value = state.at(s->fused); Expr factor = dom_map.at(s->inner)->extent; Expr outer_min = dom_map.at(s->outer)->min; Expr inner_min = dom_map.at(s->inner)->min; state[s->outer] = ComputeExpr<Div>(value, factor); state[s->inner] = ComputeExpr<Mod>(value, factor); // add min if they exist if (!is_zero(outer_min)) { state[s->outer] = state[s->outer] + outer_min; } if (!is_zero(inner_min)) { state[s->inner] = state[s->inner] + inner_min; } } else if (const RebaseNode* s = rel.as<RebaseNode>()) { if (!state.count(s->rebased)) { CHECK(allow_missing); continue; } Expr value = state.at(s->rebased); Expr parent_min = dom_map.at(s->parent)->min; // add min if they exist if (!is_zero(parent_min)) { state[s->parent] = value + parent_min; } else { state[s->parent] = value; } } else { LOG(FATAL) << "unknown relation type"; } } } void PassDownIndex(const Stage& stage, const Map<IterVar, Range>& dom_map, std::unordered_map<IterVar, Expr>* p_state, bool allow_missing) { auto& state = *p_state; for (IterVarRelation rel : stage->relations) { if (const SplitNode* s = rel.as<SplitNode>()) { if (!state.count(s->parent)) { CHECK(allow_missing); continue; } Range r = dom_map.at(s->inner); CHECK(is_zero(r->min)); Expr parent = state.at(s->parent); Expr factor = r->extent; state[s->outer] = ComputeExpr<Div>(parent, factor); state[s->inner] = ComputeExpr<Mod>(parent, factor); } else if (const FuseNode* s = rel.as<FuseNode>()) { if (!state.count(s->inner) && !state.count(s->outer)) { CHECK(allow_missing); continue; } Expr factor = dom_map.at(s->inner)->extent; Expr outer_min = dom_map.at(s->outer)->min; Expr inner_min = dom_map.at(s->inner)->min; Expr inner = state.at(s->inner); Expr outer = state.at(s->outer); CHECK(is_zero(outer_min)); CHECK(is_zero(inner_min)); state[s->fused] = outer * factor + inner; } else if (const RebaseNode* s = rel.as<RebaseNode>()) { if (!state.count(s->rebased)) { CHECK(allow_missing); continue; } Expr value = state.at(s->parent); Expr parent_min = dom_map.at(s->parent)->min; CHECK(is_zero(parent_min)); state[s->rebased] = value; } else { LOG(FATAL) << "unknown relation type"; } } } // Domain message passing. void PassUpDomain(const SplitNode* s, const std::unordered_map<IterVar, Range>& dom_map, const IntSet& outer, const IntSet& inner, IntSet* parent) { if (dom_map.count(s->outer) && dom_map.count(s->inner) && dom_map.count(s->parent) && outer.match_range(dom_map.at(s->outer)) && inner.match_range(dom_map.at(s->inner))) { *parent = IntSet::range(dom_map.at(s->parent)); return; } Expr factor = dom_map.at(s->inner)->extent; Expr parent_min = dom_map.at(s->parent)->min; CHECK(outer.defined()); CHECK(inner.defined()); CHECK(factor.defined()); *parent = EvalSet( s->outer->var * factor + s->inner->var + parent_min, {{s->outer, outer}, {s->inner, inner}}); } void PassUpDomain(const FuseNode* s, const std::unordered_map<IterVar, Range>& dom_map, const IntSet& fused, IntSet* outer, IntSet* inner) { CHECK(dom_map.count(s->outer)); CHECK(dom_map.count(s->inner)); CHECK(dom_map.count(s->fused)); if (fused.match_range(dom_map.at(s->fused))) { *outer = IntSet::range(dom_map.at(s->outer)); *inner = IntSet::range(dom_map.at(s->inner)); return; } Expr outer_min = dom_map.at(s->outer)->min; Expr inner_min = dom_map.at(s->inner)->min; if (fused.is_single_point()) { Expr value = fused.point_value(); Expr factor = dom_map.at(s->inner)->extent; Expr v_outer = value / factor; Expr v_inner = value % factor; if (!is_zero(outer_min)) v_outer = v_outer + outer_min; if (!is_zero(inner_min)) v_inner = v_inner + inner_min; *outer = IntSet::single_point(v_outer); *inner = IntSet::single_point(v_inner); } else { LOG(WARNING) << "use fallback inference rule in fuse"; // simply use the entire set, this rule can be enhanced. *outer = IntSet::range(dom_map.at(s->outer)); *inner = IntSet::range(dom_map.at(s->inner)); return; } } void PassUpDomain(const RebaseNode* s, const std::unordered_map<IterVar, Range>& dom_map, const IntSet& rebased, IntSet* parent) { CHECK(dom_map.count(s->parent)); if (rebased.match_range(dom_map.at(s->rebased))) { *parent = IntSet::range(dom_map.at(s->parent)); return; } Expr parent_min = dom_map.at(s->parent)->min; *parent = EvalSet(s->rebased->var + parent_min, {{s->rebased, rebased}}); } void PassUpDomain(const Stage& stage, const std::unordered_map<IterVar, Range>& dom_map, std::unordered_map<IterVar, IntSet>* p_state) { auto& state = *p_state; for (size_t i = stage->relations.size(); i != 0; --i) { IterVarRelation rel = stage->relations[i - 1]; if (const SplitNode* r = rel.as<SplitNode>()) { IntSet parent; PassUpDomain(r, dom_map, state.at(r->outer), state.at(r->inner), &parent); state[r->parent] = parent; } else if (const FuseNode* r = rel.as<FuseNode>()) { IntSet outer, inner; PassUpDomain(r, dom_map, state.at(r->fused), &outer, &inner); state[r->outer] = outer; state[r->inner] = inner; } else if (const RebaseNode* r = rel.as<RebaseNode>()) { IntSet parent; PassUpDomain(r, dom_map, state.at(r->rebased), &parent); state[r->parent] = parent; } else { LOG(FATAL) << "unknown relation type"; } } } // Pass up bit mask with or relation. void PassUpBitMaskOr(const Stage& stage, std::unordered_map<IterVar, int>* p_state, bool allow_missing) { auto& state = *p_state; for (size_t i = stage->relations.size(); i != 0; --i) { IterVarRelation rel = stage->relations[i - 1]; if (const SplitNode* s = rel.as<SplitNode>()) { if (!state.count(s->inner) && !state.count(s->outer)) { CHECK(allow_missing); continue; } int res = 0; if (!state.count(s->parent)) res |= state[s->parent]; if (!state.count(s->inner)) res |= state[s->inner]; if (!state.count(s->outer)) res |= state[s->outer]; state[s->parent] = res; } else if (const FuseNode* s = rel.as<FuseNode>()) { if (!state.count(s->fused)) { CHECK(allow_missing); continue; } if (!state.count(s->outer)) { state[s->outer] = state[s->fused]; } else { state[s->outer] |= state[s->fused]; } if (!state.count(s->inner)) { state[s->inner] = state[s->fused]; } else { state[s->inner] |= state[s->fused]; } } else if (const RebaseNode* s = rel.as<RebaseNode>()) { if (!state.count(s->rebased)) { CHECK(allow_missing); continue; } if (!state.count(s->parent)) { state[s->parent] = state[s->rebased]; } else { state[s->parent] |= state[s->rebased]; } } else { LOG(FATAL) << "unknown relation type"; } } } void PassDownBitMaskOr(const Stage& stage, std::unordered_map<IterVar, int>* p_state, bool allow_missing) { auto& state = *p_state; for (IterVarRelation rel : stage->relations) { if (const SplitNode* s = rel.as<SplitNode>()) { if (!state.count(s->parent)) { CHECK(allow_missing); continue; } if (!state.count(s->outer)) { state[s->outer] = state.at(s->parent); } else { state[s->outer] |= state.at(s->parent); } if (!state.count(s->inner)) { state[s->inner] = state.at(s->parent); } else { state[s->inner] |= state.at(s->parent); } } else if (const FuseNode* s = rel.as<FuseNode>()) { if (!state.count(s->outer) && !state.count(s->inner)) { CHECK(allow_missing); continue; } int res = 0; if (state.count(s->outer)) res |= state.at(s->outer); if (state.count(s->inner)) res |= state.at(s->inner); if (state.count(s->fused)) res |= state.at(s->fused); state[s->fused] = res; } else if (const RebaseNode* s = rel.as<RebaseNode>()) { if (!state.count(s->parent)) { CHECK(allow_missing); continue; } if (!state.count(s->rebased)) { state[s->rebased] = state.at(s->parent); } else { state[s->rebased] |= state.at(s->parent); } } else { LOG(FATAL) << "unknown relation type"; } } } /*! * \brief message passing to find if boundary checking on IterVar is needed. * \param s The stage to be used. * \param p_state The message passing state * IterVar->flag */ void PassUpBoundCheck(const Stage& s, const Map<IterVar, Range>& dom_map, std::unordered_map<IterVar, bool>* p_state) { auto& state = *p_state; using HalideIR::Internal::can_prove; for (size_t i = s->relations.size(); i != 0; --i) { IterVarRelation rel = s->relations[i - 1]; if (rel.as<SplitNode>()) { const SplitNode* s = rel.as<SplitNode>(); bool outer = state.at(s->outer); bool inner = state.at(s->inner); if (dom_map.count(s->inner) && dom_map.count(s->outer)) { Expr factor = dom_map.at(s->inner)->extent; Expr step = dom_map.at(s->outer)->extent; if (outer || inner) { state[s->parent] = true; } else { if (can_prove(dom_map.at(s->parent)->extent == factor * step)) { state[s->parent] = false; } else { state[s->parent] = true; } } } else { state[s->parent] = true; } } else if (rel.as<FuseNode>()) { const FuseNode* s = rel.as<FuseNode>(); bool fused = state.at(s->fused); state[s->outer] = fused; state[s->inner] = fused; } else if (rel.as<RebaseNode>()) { const RebaseNode* s = rel.as<RebaseNode>(); state[s->parent] = state.at(s->rebased); } else { LOG(FATAL) << "unknown relation type"; } } } std::vector<Expr> MakeBoundCheck( const Stage& stage, const Map<IterVar, Range>& dom_map, const std::unordered_map<IterVar, Expr>& value_map, bool skip_ivar_domain, const std::unordered_set<IterVar>& skip_iter) { std::unordered_map<IterVar, bool> bound_state; for (IterVar iv : stage->leaf_iter_vars) { bound_state[iv] = false; } PassUpBoundCheck(stage, dom_map, &bound_state); std::vector<Expr> preds; std::unordered_map<const Variable*, IntSet> iset_dmap; // setup domain map for set analysis for (const auto& kv : dom_map) { iset_dmap[kv.first->var.get()] = IntSet::range(kv.second); } for (IterVar iv : stage->op->root_iter_vars()) { if (skip_iter.count(iv) || iv->iter_type == kOpaque) continue; Range dom = dom_map.at(iv); if (bound_state.at(iv)) { Expr value = ComputeExpr<Sub>(value_map.at(iv), dom->min); Expr vmax = EvalSet(value, iset_dmap).max(); if (vmax.type() != value.type() || !can_prove(vmax < dom->extent)) { preds.emplace_back(value < dom->extent); } } CHECK(iv->dom.defined()); if (!skip_ivar_domain && !iv->dom.same_as(dom)) { Expr value = ComputeExpr<Sub>(value_map.at(iv), iv->dom->min); IntSet s = EvalSet(value, iset_dmap); Expr vmin = s.min(); Expr vmax = s.max(); if (vmin.type() != value.type() || !can_prove(vmin >= iv->dom->min)) { preds.emplace_back(value >= 0); } if (vmax.type() != value.type() || !can_prove(vmax < iv->dom->extent)) { preds.emplace_back(value < (iv->dom->extent - iv->dom->min)); } } } return preds; } } // namespace schedule } // namespace tvm