mirror of
https://github.com/zeek/zeek.git
synced 2025-10-02 14:48:21 +00:00
splitting off script optimization CSE into its own source files
This commit is contained in:
Vern Paxson
Arne Welzel
parent
a824bb1e4b
commit
dd389c0380
5 changed files with 384 additions and 357 deletions
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@ -394,6 +394,7 @@ set(MAIN_SRCS
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script_opt/CPP/Util.cc
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script_opt/CPP/Vars.cc
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${_gen_zeek_script_cpp}
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script_opt/CSE.cc
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script_opt/Expr.cc
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script_opt/FuncInfo.cc
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script_opt/GenIDDefs.cc
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266
src/script_opt/CSE.cc
Normal file
266
src/script_opt/CSE.cc
Normal file
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@ -0,0 +1,266 @@
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// See the file "COPYING" in the main distribution directory for copyright.
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#include "zeek/script_opt/CSE.h"
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namespace zeek::detail {
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CSE_ValidityChecker::CSE_ValidityChecker(ProfileFuncs& _pfs, const std::vector<const ID*>& _ids,
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const Expr* _start_e, const Expr* _end_e)
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: pfs(_pfs), ids(_ids) {
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start_e = _start_e;
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end_e = _end_e;
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// Track whether this is a record assignment, in which case
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// we're attuned to assignments to the same field for the
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// same type of record.
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if ( start_e->Tag() == EXPR_FIELD ) {
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field = start_e->AsFieldExpr()->Field();
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// Track the type of the record, too, so we don't confuse
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// field references to different records that happen to
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// have the same offset as potential aliases.
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field_type = start_e->GetOp1()->GetType();
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}
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else
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field = -1; // flags that there's no relevant field
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}
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TraversalCode CSE_ValidityChecker::PreStmt(const Stmt* s) {
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auto t = s->Tag();
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if ( t == STMT_WHEN ) {
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// These are too hard to analyze - they result in lambda calls
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// that can affect aggregates, etc.
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is_valid = false;
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return TC_ABORTALL;
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}
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if ( t == STMT_ADD || t == STMT_DELETE )
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in_aggr_mod_stmt = true;
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return TC_CONTINUE;
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}
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TraversalCode CSE_ValidityChecker::PostStmt(const Stmt* s) {
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if ( s->Tag() == STMT_ADD || s->Tag() == STMT_DELETE )
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in_aggr_mod_stmt = false;
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return TC_CONTINUE;
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}
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TraversalCode CSE_ValidityChecker::PreExpr(const Expr* e) {
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if ( e == start_e ) {
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ASSERT(! have_start_e);
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have_start_e = true;
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// Don't analyze the expression, as it's our starting
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// point and we don't want to conflate its properties
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// with those of any intervening expressions.
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return TC_CONTINUE;
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}
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if ( e == end_e ) {
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if ( ! have_start_e )
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reporter->InternalError("CSE_ValidityChecker: saw end but not start");
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ASSERT(! have_end_e);
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have_end_e = true;
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// ... and we're now done.
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return TC_ABORTALL;
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}
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if ( ! have_start_e )
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// We don't yet have a starting point.
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return TC_CONTINUE;
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// We have a starting point, and not yet an ending point.
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auto t = e->Tag();
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switch ( t ) {
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case EXPR_ASSIGN: {
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auto lhs_ref = e->GetOp1()->AsRefExprPtr();
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auto lhs = lhs_ref->GetOp1()->AsNameExpr();
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if ( CheckID(lhs->Id(), false) )
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return TC_ABORTALL;
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// Note, we don't use CheckAggrMod() because this is a plain
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// assignment. It might be changing a variable's binding to
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// an aggregate ("aggr_var = new_aggr_val"), but we don't
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// introduce temporaries that are simply aliases of existing
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// variables (e.g., we don't have "<internal>::#8 = aggr_var"),
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// and so there's no concern that the temporary could now be
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// referring to the wrong aggregate. If instead we have
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// "<internal>::#8 = aggr_var$foo", then a reassignment here
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// to "aggr_var" will already be caught by CheckID().
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} break;
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case EXPR_INDEX_ASSIGN: {
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auto lhs_aggr = e->GetOp1();
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auto lhs_aggr_id = lhs_aggr->AsNameExpr()->Id();
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if ( CheckID(lhs_aggr_id, true) || CheckTableMod(lhs_aggr->GetType()) )
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return TC_ABORTALL;
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} break;
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case EXPR_FIELD_LHS_ASSIGN: {
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auto lhs = e->GetOp1();
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auto lhs_aggr_id = lhs->AsNameExpr()->Id();
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auto lhs_field = e->AsFieldLHSAssignExpr()->Field();
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if ( CheckID(lhs_aggr_id, true) )
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return TC_ABORTALL;
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if ( lhs_field == field && same_type(lhs_aggr_id->GetType(), field_type) ) {
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is_valid = false;
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return TC_ABORTALL;
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}
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} break;
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case EXPR_APPEND_TO:
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// This doesn't directly change any identifiers, but does
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// alter an aggregate.
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if ( CheckAggrMod(e->GetType()) )
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return TC_ABORTALL;
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break;
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case EXPR_CALL:
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if ( CheckCall(e->AsCallExpr()) )
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return TC_ABORTALL;
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break;
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case EXPR_TABLE_CONSTRUCTOR:
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// These have EXPR_ASSIGN's in them that don't
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// correspond to actual assignments to variables,
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// so we don't want to traverse them.
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return TC_ABORTSTMT;
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case EXPR_RECORD_COERCE:
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case EXPR_RECORD_CONSTRUCTOR:
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// Note, record coercion behaves like constructors in terms of
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// potentially executing &default functions. In either case,
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// the type of the expression reflects the type we want to analyze
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// for side effects.
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if ( CheckRecordConstructor(e->GetType()) )
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return TC_ABORTALL;
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break;
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case EXPR_INDEX:
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case EXPR_FIELD: {
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// We treat these together because they both have to be checked
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// when inside an "add" or "delete" statement.
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auto aggr = e->GetOp1();
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auto aggr_t = aggr->GetType();
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if ( in_aggr_mod_stmt ) {
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auto aggr_id = aggr->AsNameExpr()->Id();
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if ( CheckID(aggr_id, true) || CheckAggrMod(aggr_t) )
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return TC_ABORTALL;
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}
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else if ( t == EXPR_INDEX && aggr_t->Tag() == TYPE_TABLE ) {
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if ( CheckTableRef(aggr_t) )
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return TC_ABORTALL;
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}
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} break;
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default: break;
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}
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return TC_CONTINUE;
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}
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bool CSE_ValidityChecker::CheckID(const ID* id, bool ignore_orig) {
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for ( auto i : ids ) {
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if ( ignore_orig && i == ids.front() )
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continue;
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if ( id == i )
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return Invalid(); // reassignment
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}
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return false;
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}
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bool CSE_ValidityChecker::CheckAggrMod(const TypePtr& t) {
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if ( ! IsAggr(t) )
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return false;
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for ( auto i : ids )
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if ( same_type(t, i->GetType()) )
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return Invalid();
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return false;
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}
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bool CSE_ValidityChecker::CheckRecordConstructor(const TypePtr& t) {
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if ( t->Tag() != TYPE_RECORD )
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return false;
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return CheckSideEffects(SideEffectsOp::CONSTRUCTION, t);
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}
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bool CSE_ValidityChecker::CheckTableMod(const TypePtr& t) {
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if ( CheckAggrMod(t) )
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return true;
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if ( t->Tag() != TYPE_TABLE )
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return false;
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return CheckSideEffects(SideEffectsOp::WRITE, t);
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}
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bool CSE_ValidityChecker::CheckTableRef(const TypePtr& t) { return CheckSideEffects(SideEffectsOp::READ, t); }
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bool CSE_ValidityChecker::CheckCall(const CallExpr* c) {
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auto func = c->Func();
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std::string desc;
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if ( func->Tag() != EXPR_NAME )
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// Can't analyze indirect calls.
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return Invalid();
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IDSet non_local_ids;
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TypeSet aggrs;
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bool is_unknown = false;
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auto resolved = pfs.GetCallSideEffects(func->AsNameExpr(), non_local_ids, aggrs, is_unknown);
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ASSERT(resolved);
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if ( is_unknown || CheckSideEffects(non_local_ids, aggrs) )
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return Invalid();
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return false;
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}
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bool CSE_ValidityChecker::CheckSideEffects(SideEffectsOp::AccessType access, const TypePtr& t) {
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IDSet non_local_ids;
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TypeSet aggrs;
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if ( pfs.GetSideEffects(access, t.get(), non_local_ids, aggrs) )
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return Invalid();
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return CheckSideEffects(non_local_ids, aggrs);
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}
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bool CSE_ValidityChecker::CheckSideEffects(const IDSet& non_local_ids, const TypeSet& aggrs) {
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if ( non_local_ids.empty() && aggrs.empty() )
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// This is far and away the most common case.
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return false;
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for ( auto i : ids ) {
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for ( auto nli : non_local_ids )
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if ( nli == i )
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return Invalid();
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auto i_t = i->GetType();
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for ( auto a : aggrs )
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if ( same_type(a, i_t.get()) )
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return Invalid();
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}
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return false;
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}
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} // namespace zeek::detail
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116
src/script_opt/CSE.h
Normal file
116
src/script_opt/CSE.h
Normal file
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@ -0,0 +1,116 @@
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// See the file "COPYING" in the main distribution directory for copyright.
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#pragma once
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#include "zeek/script_opt/ProfileFunc.h"
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namespace zeek::detail {
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class TempVar;
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// Helper class that walks an AST to determine whether it's safe to
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// substitute a common subexpression (which at this point is an assignment
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// to a variable) created using the assignment expression at position "start_e",
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// at the location specified by the expression at position "end_e".
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//
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// See Reducer::ExprValid for a discussion of what's required for safety.
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class CSE_ValidityChecker : public TraversalCallback {
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public:
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CSE_ValidityChecker(ProfileFuncs& pfs, const std::vector<const ID*>& ids, const Expr* start_e,
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const Expr* end_e);
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TraversalCode PreStmt(const Stmt*) override;
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TraversalCode PostStmt(const Stmt*) override;
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TraversalCode PreExpr(const Expr*) override;
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// Returns the ultimate verdict re safety.
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bool IsValid() const {
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if ( ! is_valid )
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return false;
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if ( ! have_end_e )
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reporter->InternalError("CSE_ValidityChecker: saw start but not end");
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return true;
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}
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protected:
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// Returns true if an assignment involving the given identifier on
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// the LHS is in conflict with the identifiers we're tracking.
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bool CheckID(const ID* id, bool ignore_orig);
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// Returns true if a modification to an aggregate of the given type
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// potentially aliases with one of the identifiers we're tracking.
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bool CheckAggrMod(const TypePtr& t);
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// Returns true if a record constructor/coercion of the given type has
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// side effects and invalides the CSE opportunity.
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bool CheckRecordConstructor(const TypePtr& t);
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// The same for modifications to tables.
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bool CheckTableMod(const TypePtr& t);
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// The same for accessing (reading) tables.
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bool CheckTableRef(const TypePtr& t);
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// The same for the given function call.
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bool CheckCall(const CallExpr* c);
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// True if the given form of access to the given type has side effects.
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bool CheckSideEffects(SideEffectsOp::AccessType access, const TypePtr& t);
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// True if side effects to the given identifiers and aggregates invalidate
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// the CSE opportunity.
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bool CheckSideEffects(const IDSet& non_local_ids, const TypeSet& aggrs);
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// Helper function that marks the CSE opportunity as invalid and returns
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// "true" (used by various methods to signal invalidation).
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bool Invalid() {
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is_valid = false;
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return true;
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}
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// Profile across all script functions.
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ProfileFuncs& pfs;
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// The list of identifiers for which an assignment to one of them
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// renders the CSE unsafe.
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const std::vector<const ID*>& ids;
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// Where in the AST to start our analysis. This is the initial
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// assignment expression.
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const Expr* start_e;
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// Where in the AST to end our analysis.
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const Expr* end_e;
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// If what we're analyzing is a record element, then its offset.
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// -1 if not.
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int field;
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// The type of that record element, if any.
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TypePtr field_type;
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// The verdict so far.
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bool is_valid = true;
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// Whether we've encountered the start/end expression in
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// the AST traversal.
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bool have_start_e = false;
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bool have_end_e = false;
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// Whether analyzed expressions occur in the context of a statement
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// that modifies an aggregate ("add" or "delete"), which changes the
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// interpretation of the expressions.
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bool in_aggr_mod_stmt = false;
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};
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// Used for debugging, to communicate which expression wasn't
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// reduced when we expected them all to be.
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extern const Expr* non_reduced_perp;
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extern bool checking_reduction;
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// Used to report a non-reduced expression.
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extern bool NonReduced(const Expr* perp);
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} // namespace zeek::detail
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@ -825,265 +825,6 @@ std::shared_ptr<TempVar> Reducer::FindTemporary(const ID* id) const {
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return tmp->second;
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}
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CSE_ValidityChecker::CSE_ValidityChecker(ProfileFuncs& _pfs, const std::vector<const ID*>& _ids, const Expr* _start_e,
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const Expr* _end_e)
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: pfs(_pfs), ids(_ids) {
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start_e = _start_e;
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end_e = _end_e;
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// Track whether this is a record assignment, in which case
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// we're attuned to assignments to the same field for the
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// same type of record.
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if ( start_e->Tag() == EXPR_FIELD ) {
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field = start_e->AsFieldExpr()->Field();
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// Track the type of the record, too, so we don't confuse
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// field references to different records that happen to
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// have the same offset as potential aliases.
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field_type = start_e->GetOp1()->GetType();
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}
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else
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field = -1; // flags that there's no relevant field
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}
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TraversalCode CSE_ValidityChecker::PreStmt(const Stmt* s) {
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auto t = s->Tag();
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if ( t == STMT_WHEN ) {
|
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// These are too hard to analyze - they result in lambda calls
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// that can affect aggregates, etc.
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is_valid = false;
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return TC_ABORTALL;
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}
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if ( t == STMT_ADD || t == STMT_DELETE )
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in_aggr_mod_stmt = true;
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return TC_CONTINUE;
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}
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TraversalCode CSE_ValidityChecker::PostStmt(const Stmt* s) {
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if ( s->Tag() == STMT_ADD || s->Tag() == STMT_DELETE )
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in_aggr_mod_stmt = false;
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return TC_CONTINUE;
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}
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TraversalCode CSE_ValidityChecker::PreExpr(const Expr* e) {
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if ( e == start_e ) {
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ASSERT(! have_start_e);
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have_start_e = true;
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// Don't analyze the expression, as it's our starting
|
||||
// point and we don't want to conflate its properties
|
||||
// with those of any intervening expressions.
|
||||
return TC_CONTINUE;
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}
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if ( e == end_e ) {
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if ( ! have_start_e )
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reporter->InternalError("CSE_ValidityChecker: saw end but not start");
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ASSERT(! have_end_e);
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have_end_e = true;
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// ... and we're now done.
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return TC_ABORTALL;
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}
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if ( ! have_start_e )
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// We don't yet have a starting point.
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return TC_CONTINUE;
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// We have a starting point, and not yet an ending point.
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auto t = e->Tag();
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switch ( t ) {
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case EXPR_ASSIGN: {
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auto lhs_ref = e->GetOp1()->AsRefExprPtr();
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auto lhs = lhs_ref->GetOp1()->AsNameExpr();
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if ( CheckID(lhs->Id(), false) )
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return TC_ABORTALL;
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||||
|
||||
// Note, we don't use CheckAggrMod() because this is a plain
|
||||
// assignment. It might be changing a variable's binding to
|
||||
// an aggregate ("aggr_var = new_aggr_val"), but we don't
|
||||
// introduce temporaries that are simply aliases of existing
|
||||
// variables (e.g., we don't have "<internal>::#8 = aggr_var"),
|
||||
// and so there's no concern that the temporary could now be
|
||||
// referring to the wrong aggregate. If instead we have
|
||||
// "<internal>::#8 = aggr_var$foo", then a reassignment here
|
||||
// to "aggr_var" will already be caught by CheckID().
|
||||
} break;
|
||||
|
||||
case EXPR_INDEX_ASSIGN: {
|
||||
auto lhs_aggr = e->GetOp1();
|
||||
auto lhs_aggr_id = lhs_aggr->AsNameExpr()->Id();
|
||||
|
||||
if ( CheckID(lhs_aggr_id, true) || CheckTableMod(lhs_aggr->GetType()) )
|
||||
return TC_ABORTALL;
|
||||
} break;
|
||||
|
||||
case EXPR_FIELD_LHS_ASSIGN: {
|
||||
auto lhs = e->GetOp1();
|
||||
auto lhs_aggr_id = lhs->AsNameExpr()->Id();
|
||||
auto lhs_field = e->AsFieldLHSAssignExpr()->Field();
|
||||
|
||||
if ( CheckID(lhs_aggr_id, true) )
|
||||
return TC_ABORTALL;
|
||||
if ( lhs_field == field && same_type(lhs_aggr_id->GetType(), field_type) ) {
|
||||
is_valid = false;
|
||||
return TC_ABORTALL;
|
||||
}
|
||||
} break;
|
||||
|
||||
case EXPR_APPEND_TO:
|
||||
// This doesn't directly change any identifiers, but does
|
||||
// alter an aggregate.
|
||||
if ( CheckAggrMod(e->GetType()) )
|
||||
return TC_ABORTALL;
|
||||
break;
|
||||
|
||||
case EXPR_CALL:
|
||||
if ( CheckCall(e->AsCallExpr()) )
|
||||
return TC_ABORTALL;
|
||||
break;
|
||||
|
||||
case EXPR_TABLE_CONSTRUCTOR:
|
||||
// These have EXPR_ASSIGN's in them that don't
|
||||
// correspond to actual assignments to variables,
|
||||
// so we don't want to traverse them.
|
||||
return TC_ABORTSTMT;
|
||||
|
||||
case EXPR_RECORD_COERCE:
|
||||
case EXPR_RECORD_CONSTRUCTOR:
|
||||
// Note, record coercion behaves like constructors in terms of
|
||||
// potentially executing &default functions. In either case,
|
||||
// the type of the expression reflects the type we want to analyze
|
||||
// for side effects.
|
||||
if ( CheckRecordConstructor(e->GetType()) )
|
||||
return TC_ABORTALL;
|
||||
break;
|
||||
|
||||
case EXPR_INDEX:
|
||||
case EXPR_FIELD: {
|
||||
// We treat these together because they both have to be checked
|
||||
// when inside an "add" or "delete" statement.
|
||||
auto aggr = e->GetOp1();
|
||||
auto aggr_t = aggr->GetType();
|
||||
|
||||
if ( in_aggr_mod_stmt ) {
|
||||
auto aggr_id = aggr->AsNameExpr()->Id();
|
||||
|
||||
if ( CheckID(aggr_id, true) || CheckAggrMod(aggr_t) )
|
||||
return TC_ABORTALL;
|
||||
}
|
||||
|
||||
else if ( t == EXPR_INDEX && aggr_t->Tag() == TYPE_TABLE ) {
|
||||
if ( CheckTableRef(aggr_t) )
|
||||
return TC_ABORTALL;
|
||||
}
|
||||
} break;
|
||||
|
||||
default: break;
|
||||
}
|
||||
|
||||
return TC_CONTINUE;
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckID(const ID* id, bool ignore_orig) {
|
||||
for ( auto i : ids ) {
|
||||
if ( ignore_orig && i == ids.front() )
|
||||
continue;
|
||||
|
||||
if ( id == i )
|
||||
return Invalid(); // reassignment
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckAggrMod(const TypePtr& t) {
|
||||
if ( ! IsAggr(t) )
|
||||
return false;
|
||||
|
||||
for ( auto i : ids )
|
||||
if ( same_type(t, i->GetType()) )
|
||||
return Invalid();
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckRecordConstructor(const TypePtr& t) {
|
||||
if ( t->Tag() != TYPE_RECORD )
|
||||
return false;
|
||||
|
||||
return CheckSideEffects(SideEffectsOp::CONSTRUCTION, t);
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckTableMod(const TypePtr& t) {
|
||||
if ( CheckAggrMod(t) )
|
||||
return true;
|
||||
|
||||
if ( t->Tag() != TYPE_TABLE )
|
||||
return false;
|
||||
|
||||
return CheckSideEffects(SideEffectsOp::WRITE, t);
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckTableRef(const TypePtr& t) { return CheckSideEffects(SideEffectsOp::READ, t); }
|
||||
|
||||
bool CSE_ValidityChecker::CheckCall(const CallExpr* c) {
|
||||
auto func = c->Func();
|
||||
std::string desc;
|
||||
if ( func->Tag() != EXPR_NAME )
|
||||
// Can't analyze indirect calls.
|
||||
return Invalid();
|
||||
|
||||
IDSet non_local_ids;
|
||||
TypeSet aggrs;
|
||||
bool is_unknown = false;
|
||||
|
||||
auto resolved = pfs.GetCallSideEffects(func->AsNameExpr(), non_local_ids, aggrs, is_unknown);
|
||||
ASSERT(resolved);
|
||||
|
||||
if ( is_unknown || CheckSideEffects(non_local_ids, aggrs) )
|
||||
return Invalid();
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckSideEffects(SideEffectsOp::AccessType access, const TypePtr& t) {
|
||||
IDSet non_local_ids;
|
||||
TypeSet aggrs;
|
||||
|
||||
if ( pfs.GetSideEffects(access, t.get(), non_local_ids, aggrs) )
|
||||
return Invalid();
|
||||
|
||||
return CheckSideEffects(non_local_ids, aggrs);
|
||||
}
|
||||
|
||||
bool CSE_ValidityChecker::CheckSideEffects(const IDSet& non_local_ids, const TypeSet& aggrs) {
|
||||
if ( non_local_ids.empty() && aggrs.empty() )
|
||||
// This is far and away the most common case.
|
||||
return false;
|
||||
|
||||
for ( auto i : ids ) {
|
||||
for ( auto nli : non_local_ids )
|
||||
if ( nli == i )
|
||||
return Invalid();
|
||||
|
||||
auto i_t = i->GetType();
|
||||
for ( auto a : aggrs )
|
||||
if ( same_type(a, i_t.get()) )
|
||||
return Invalid();
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
const Expr* non_reduced_perp;
|
||||
bool checking_reduction;
|
||||
|
||||
|
|
|
|||
|
|
@ -6,6 +6,7 @@
|
|||
#include "zeek/Scope.h"
|
||||
#include "zeek/Stmt.h"
|
||||
#include "zeek/Traverse.h"
|
||||
#include "zeek/script_opt/CSE.h"
|
||||
#include "zeek/script_opt/ObjMgr.h"
|
||||
#include "zeek/script_opt/ProfileFunc.h"
|
||||
|
||||
|
|
@ -314,104 +315,6 @@ protected:
|
|||
bool opt_ready = false;
|
||||
};
|
||||
|
||||
// Helper class that walks an AST to determine whether it's safe
|
||||
// to substitute a common subexpression (which at this point is
|
||||
// an assignment to a variable) created using the assignment
|
||||
// expression at position "start_e", at the location specified by
|
||||
// the expression at position "end_e".
|
||||
//
|
||||
// See Reducer::ExprValid for a discussion of what's required
|
||||
// for safety.
|
||||
|
||||
class CSE_ValidityChecker : public TraversalCallback {
|
||||
public:
|
||||
CSE_ValidityChecker(ProfileFuncs& pfs, const std::vector<const ID*>& ids, const Expr* start_e, const Expr* end_e);
|
||||
|
||||
TraversalCode PreStmt(const Stmt*) override;
|
||||
TraversalCode PostStmt(const Stmt*) override;
|
||||
TraversalCode PreExpr(const Expr*) override;
|
||||
|
||||
// Returns the ultimate verdict re safety.
|
||||
bool IsValid() const {
|
||||
if ( ! is_valid )
|
||||
return false;
|
||||
|
||||
if ( ! have_end_e )
|
||||
reporter->InternalError("CSE_ValidityChecker: saw start but not end");
|
||||
return true;
|
||||
}
|
||||
|
||||
protected:
|
||||
// Returns true if an assignment involving the given identifier on
|
||||
// the LHS is in conflict with the identifiers we're tracking.
|
||||
bool CheckID(const ID* id, bool ignore_orig);
|
||||
|
||||
// Returns true if a modification to an aggregate of the given type
|
||||
// potentially aliases with one of the identifiers we're tracking.
|
||||
bool CheckAggrMod(const TypePtr& t);
|
||||
|
||||
// Returns true if a record constructor/coercion of the given type has
|
||||
// side effects and invalides the CSE opportunity.
|
||||
bool CheckRecordConstructor(const TypePtr& t);
|
||||
|
||||
// The same for modifications to tables.
|
||||
bool CheckTableMod(const TypePtr& t);
|
||||
|
||||
// The same for accessing (reading) tables.
|
||||
bool CheckTableRef(const TypePtr& t);
|
||||
|
||||
// The same for the given function call.
|
||||
bool CheckCall(const CallExpr* c);
|
||||
|
||||
// True if the given form of access to the given type has side effects.
|
||||
bool CheckSideEffects(SideEffectsOp::AccessType access, const TypePtr& t);
|
||||
|
||||
// True if side effects to the given identifiers and aggregates invalidate
|
||||
// the CSE opportunity.
|
||||
bool CheckSideEffects(const IDSet& non_local_ids, const TypeSet& aggrs);
|
||||
|
||||
// Helper function that marks the CSE opportunity as invalid and returns
|
||||
// "true" (used by various methods to signal invalidation).
|
||||
bool Invalid() {
|
||||
is_valid = false;
|
||||
return true;
|
||||
}
|
||||
|
||||
// Profile across all script functions.
|
||||
ProfileFuncs& pfs;
|
||||
|
||||
// The list of identifiers for which an assignment to one of them
|
||||
// renders the CSE unsafe.
|
||||
const std::vector<const ID*>& ids;
|
||||
|
||||
// Where in the AST to start our analysis. This is the initial
|
||||
// assignment expression.
|
||||
const Expr* start_e;
|
||||
|
||||
// Where in the AST to end our analysis.
|
||||
const Expr* end_e;
|
||||
|
||||
// If what we're analyzing is a record element, then its offset.
|
||||
// -1 if not.
|
||||
int field;
|
||||
|
||||
// The type of that record element, if any.
|
||||
TypePtr field_type;
|
||||
|
||||
// The verdict so far.
|
||||
bool is_valid = true;
|
||||
|
||||
// Whether we've encountered the start/end expression in
|
||||
// the AST traversal.
|
||||
bool have_start_e = false;
|
||||
bool have_end_e = false;
|
||||
|
||||
// Whether analyzed expressions occur in the context of a statement
|
||||
// that modifies an aggregate ("add" or "delete"), which changes the
|
||||
// interpretation of the expressions.
|
||||
bool in_aggr_mod_stmt = false;
|
||||
};
|
||||
|
||||
// Used for debugging, to communicate which expression wasn't
|
||||
// reduced when we expected them all to be.
|
||||
extern const Expr* non_reduced_perp;
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue