mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-11-29 22:41:03 +00:00
CFA: Pull in CalculateDominators
This commit is contained in:
parent
df6537cee0
commit
d6f2979068
92
source/cfa.h
92
source/cfa.h
@ -82,6 +82,29 @@ public:
|
|||||||
std::function<void(cbb_ptr)> preorder,
|
std::function<void(cbb_ptr)> preorder,
|
||||||
std::function<void(cbb_ptr)> postorder,
|
std::function<void(cbb_ptr)> postorder,
|
||||||
std::function<void(cbb_ptr, cbb_ptr)> backedge);
|
std::function<void(cbb_ptr, cbb_ptr)> backedge);
|
||||||
|
|
||||||
|
/// @brief Calculates dominator edges for a set of blocks
|
||||||
|
///
|
||||||
|
/// Computes dominators using the algorithm of Cooper, Harvey, and Kennedy
|
||||||
|
/// "A Simple, Fast Dominance Algorithm", 2001.
|
||||||
|
///
|
||||||
|
/// The algorithm assumes there is a unique root node (a node without
|
||||||
|
/// predecessors), and it is therefore at the end of the postorder vector.
|
||||||
|
///
|
||||||
|
/// This function calculates the dominator edges for a set of blocks in the CFG.
|
||||||
|
/// Uses the dominator algorithm by Cooper et al.
|
||||||
|
///
|
||||||
|
/// @param[in] postorder A vector of blocks in post order traversal order
|
||||||
|
/// in a CFG
|
||||||
|
/// @param[in] predecessor_func Function used to get the predecessor nodes of a
|
||||||
|
/// block
|
||||||
|
///
|
||||||
|
/// @return the dominator tree of the graph, as a vector of pairs of nodes.
|
||||||
|
/// The first node in the pair is a node in the graph. The second node in the
|
||||||
|
/// pair is its immediate dominator in the sense of Cooper et.al., where a block
|
||||||
|
/// without predecessors (such as the root node) is its own immediate dominator.
|
||||||
|
static vector<pair<BB*, BB*>> CalculateDominators(
|
||||||
|
const vector<cbb_ptr>& postorder, get_blocks_func predecessor_func);
|
||||||
};
|
};
|
||||||
|
|
||||||
template<class BB> bool CFA<BB>::FindInWorkList(const vector<block_info>& work_list,
|
template<class BB> bool CFA<BB>::FindInWorkList(const vector<block_info>& work_list,
|
||||||
@ -130,6 +153,75 @@ template<class BB> void CFA<BB>::DepthFirstTraversal(const BB* entry,
|
|||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
template<class BB>
|
||||||
|
vector<pair<BB*, BB*>> CFA<BB>::CalculateDominators(
|
||||||
|
const vector<cbb_ptr>& postorder, get_blocks_func predecessor_func) {
|
||||||
|
struct block_detail {
|
||||||
|
size_t dominator; ///< The index of blocks's dominator in post order array
|
||||||
|
size_t postorder_index; ///< The index of the block in the post order array
|
||||||
|
};
|
||||||
|
const size_t undefined_dom = postorder.size();
|
||||||
|
|
||||||
|
unordered_map<cbb_ptr, block_detail> idoms;
|
||||||
|
for (size_t i = 0; i < postorder.size(); i++) {
|
||||||
|
idoms[postorder[i]] = { undefined_dom, i };
|
||||||
|
}
|
||||||
|
idoms[postorder.back()].dominator = idoms[postorder.back()].postorder_index;
|
||||||
|
|
||||||
|
bool changed = true;
|
||||||
|
while (changed) {
|
||||||
|
changed = false;
|
||||||
|
for (auto b = postorder.rbegin() + 1; b != postorder.rend(); ++b) {
|
||||||
|
const vector<BB*>& predecessors = *predecessor_func(*b);
|
||||||
|
// Find the first processed/reachable predecessor that is reachable
|
||||||
|
// in the forward traversal.
|
||||||
|
auto res = find_if(begin(predecessors), end(predecessors),
|
||||||
|
[&idoms, undefined_dom](BB* pred) {
|
||||||
|
return idoms.count(pred) &&
|
||||||
|
idoms[pred].dominator != undefined_dom;
|
||||||
|
});
|
||||||
|
if (res == end(predecessors)) continue;
|
||||||
|
const BB* idom = *res;
|
||||||
|
size_t idom_idx = idoms[idom].postorder_index;
|
||||||
|
|
||||||
|
// all other predecessors
|
||||||
|
for (const auto* p : predecessors) {
|
||||||
|
if (idom == p) continue;
|
||||||
|
// Only consider nodes reachable in the forward traversal.
|
||||||
|
// Otherwise the intersection doesn't make sense and will never
|
||||||
|
// terminate.
|
||||||
|
if (!idoms.count(p)) continue;
|
||||||
|
if (idoms[p].dominator != undefined_dom) {
|
||||||
|
size_t finger1 = idoms[p].postorder_index;
|
||||||
|
size_t finger2 = idom_idx;
|
||||||
|
while (finger1 != finger2) {
|
||||||
|
while (finger1 < finger2) {
|
||||||
|
finger1 = idoms[postorder[finger1]].dominator;
|
||||||
|
}
|
||||||
|
while (finger2 < finger1) {
|
||||||
|
finger2 = idoms[postorder[finger2]].dominator;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
idom_idx = finger1;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
if (idoms[*b].dominator != idom_idx) {
|
||||||
|
idoms[*b].dominator = idom_idx;
|
||||||
|
changed = true;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
vector<pair<bb_ptr, bb_ptr>> out;
|
||||||
|
for (auto idom : idoms) {
|
||||||
|
// NOTE: performing a const cast for convenient usage with
|
||||||
|
// UpdateImmediateDominators
|
||||||
|
out.push_back({ const_cast<BB*>(get<0>(idom)),
|
||||||
|
const_cast<BB*>(postorder[get<1>(idom).dominator]) });
|
||||||
|
}
|
||||||
|
return out;
|
||||||
|
}
|
||||||
|
|
||||||
} // namespace spvtools
|
} // namespace spvtools
|
||||||
|
|
||||||
#endif // SPVTOOLS_CFA_H_
|
#endif // SPVTOOLS_CFA_H_
|
||||||
|
@ -34,30 +34,6 @@ class BasicBlock;
|
|||||||
using get_blocks_func =
|
using get_blocks_func =
|
||||||
std::function<const std::vector<BasicBlock*>*(const BasicBlock*)>;
|
std::function<const std::vector<BasicBlock*>*(const BasicBlock*)>;
|
||||||
|
|
||||||
/// @brief Calculates dominator edges for a set of blocks
|
|
||||||
///
|
|
||||||
/// Computes dominators using the algorithm of Cooper, Harvey, and Kennedy
|
|
||||||
/// "A Simple, Fast Dominance Algorithm", 2001.
|
|
||||||
///
|
|
||||||
/// The algorithm assumes there is a unique root node (a node without
|
|
||||||
/// predecessors), and it is therefore at the end of the postorder vector.
|
|
||||||
///
|
|
||||||
/// This function calculates the dominator edges for a set of blocks in the CFG.
|
|
||||||
/// Uses the dominator algorithm by Cooper et al.
|
|
||||||
///
|
|
||||||
/// @param[in] postorder A vector of blocks in post order traversal order
|
|
||||||
/// in a CFG
|
|
||||||
/// @param[in] predecessor_func Function used to get the predecessor nodes of a
|
|
||||||
/// block
|
|
||||||
///
|
|
||||||
/// @return the dominator tree of the graph, as a vector of pairs of nodes.
|
|
||||||
/// The first node in the pair is a node in the graph. The second node in the
|
|
||||||
/// pair is its immediate dominator in the sense of Cooper et.al., where a block
|
|
||||||
/// without predecessors (such as the root node) is its own immediate dominator.
|
|
||||||
std::vector<std::pair<BasicBlock*, BasicBlock*>> CalculateDominators(
|
|
||||||
const std::vector<const BasicBlock*>& postorder,
|
|
||||||
get_blocks_func predecessor_func);
|
|
||||||
|
|
||||||
/// @brief Performs the Control Flow Graph checks
|
/// @brief Performs the Control Flow Graph checks
|
||||||
///
|
///
|
||||||
/// @param[in] _ the validation state of the module
|
/// @param[in] _ the validation state of the module
|
||||||
|
@ -61,74 +61,6 @@ using bb_iter = vector<BasicBlock*>::const_iterator;
|
|||||||
|
|
||||||
} // namespace
|
} // namespace
|
||||||
|
|
||||||
vector<pair<BasicBlock*, BasicBlock*>> CalculateDominators(
|
|
||||||
const vector<cbb_ptr>& postorder, get_blocks_func predecessor_func) {
|
|
||||||
struct block_detail {
|
|
||||||
size_t dominator; ///< The index of blocks's dominator in post order array
|
|
||||||
size_t postorder_index; ///< The index of the block in the post order array
|
|
||||||
};
|
|
||||||
const size_t undefined_dom = postorder.size();
|
|
||||||
|
|
||||||
unordered_map<cbb_ptr, block_detail> idoms;
|
|
||||||
for (size_t i = 0; i < postorder.size(); i++) {
|
|
||||||
idoms[postorder[i]] = {undefined_dom, i};
|
|
||||||
}
|
|
||||||
idoms[postorder.back()].dominator = idoms[postorder.back()].postorder_index;
|
|
||||||
|
|
||||||
bool changed = true;
|
|
||||||
while (changed) {
|
|
||||||
changed = false;
|
|
||||||
for (auto b = postorder.rbegin() + 1; b != postorder.rend(); ++b) {
|
|
||||||
const vector<BasicBlock*>& predecessors = *predecessor_func(*b);
|
|
||||||
// Find the first processed/reachable predecessor that is reachable
|
|
||||||
// in the forward traversal.
|
|
||||||
auto res = find_if(begin(predecessors), end(predecessors),
|
|
||||||
[&idoms, undefined_dom](BasicBlock* pred) {
|
|
||||||
return idoms.count(pred) &&
|
|
||||||
idoms[pred].dominator != undefined_dom;
|
|
||||||
});
|
|
||||||
if (res == end(predecessors)) continue;
|
|
||||||
const BasicBlock* idom = *res;
|
|
||||||
size_t idom_idx = idoms[idom].postorder_index;
|
|
||||||
|
|
||||||
// all other predecessors
|
|
||||||
for (const auto* p : predecessors) {
|
|
||||||
if (idom == p) continue;
|
|
||||||
// Only consider nodes reachable in the forward traversal.
|
|
||||||
// Otherwise the intersection doesn't make sense and will never
|
|
||||||
// terminate.
|
|
||||||
if (!idoms.count(p)) continue;
|
|
||||||
if (idoms[p].dominator != undefined_dom) {
|
|
||||||
size_t finger1 = idoms[p].postorder_index;
|
|
||||||
size_t finger2 = idom_idx;
|
|
||||||
while (finger1 != finger2) {
|
|
||||||
while (finger1 < finger2) {
|
|
||||||
finger1 = idoms[postorder[finger1]].dominator;
|
|
||||||
}
|
|
||||||
while (finger2 < finger1) {
|
|
||||||
finger2 = idoms[postorder[finger2]].dominator;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
idom_idx = finger1;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
if (idoms[*b].dominator != idom_idx) {
|
|
||||||
idoms[*b].dominator = idom_idx;
|
|
||||||
changed = true;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
vector<pair<bb_ptr, bb_ptr>> out;
|
|
||||||
for (auto idom : idoms) {
|
|
||||||
// NOTE: performing a const cast for convenient usage with
|
|
||||||
// UpdateImmediateDominators
|
|
||||||
out.push_back({const_cast<BasicBlock*>(get<0>(idom)),
|
|
||||||
const_cast<BasicBlock*>(postorder[get<1>(idom).dominator])});
|
|
||||||
}
|
|
||||||
return out;
|
|
||||||
}
|
|
||||||
|
|
||||||
void printDominatorList(const BasicBlock& b) {
|
void printDominatorList(const BasicBlock& b) {
|
||||||
std::cout << b.id() << " is dominated by: ";
|
std::cout << b.id() << " is dominated by: ";
|
||||||
const BasicBlock* bb = &b;
|
const BasicBlock* bb = &b;
|
||||||
@ -355,7 +287,7 @@ spv_result_t PerformCfgChecks(ValidationState_t& _) {
|
|||||||
function.first_block(), function.AugmentedCFGSuccessorsFunction(),
|
function.first_block(), function.AugmentedCFGSuccessorsFunction(),
|
||||||
ignore_block, [&](cbb_ptr b) { postorder.push_back(b); },
|
ignore_block, [&](cbb_ptr b) { postorder.push_back(b); },
|
||||||
ignore_edge);
|
ignore_edge);
|
||||||
auto edges = libspirv::CalculateDominators(
|
auto edges = spvtools::CFA<libspirv::BasicBlock>::CalculateDominators(
|
||||||
postorder, function.AugmentedCFGPredecessorsFunction());
|
postorder, function.AugmentedCFGPredecessorsFunction());
|
||||||
for (auto edge : edges) {
|
for (auto edge : edges) {
|
||||||
edge.first->SetImmediateDominator(edge.second);
|
edge.first->SetImmediateDominator(edge.second);
|
||||||
@ -366,7 +298,7 @@ spv_result_t PerformCfgChecks(ValidationState_t& _) {
|
|||||||
function.pseudo_exit_block(),
|
function.pseudo_exit_block(),
|
||||||
function.AugmentedCFGPredecessorsFunction(), ignore_block,
|
function.AugmentedCFGPredecessorsFunction(), ignore_block,
|
||||||
[&](cbb_ptr b) { postdom_postorder.push_back(b); }, ignore_edge);
|
[&](cbb_ptr b) { postdom_postorder.push_back(b); }, ignore_edge);
|
||||||
auto postdom_edges = libspirv::CalculateDominators(
|
auto postdom_edges = spvtools::CFA<libspirv::BasicBlock>::CalculateDominators(
|
||||||
postdom_postorder, function.AugmentedCFGSuccessorsFunction());
|
postdom_postorder, function.AugmentedCFGSuccessorsFunction());
|
||||||
for (auto edge : postdom_edges) {
|
for (auto edge : postdom_edges) {
|
||||||
edge.first->SetImmediatePostDominator(edge.second);
|
edge.first->SetImmediatePostDominator(edge.second);
|
||||||
|
Loading…
Reference in New Issue
Block a user