From bfca9505f6fce631c2488f89aa156d56c7fae9ed Mon Sep 17 00:00:00 2001 From: David Malcolm Date: Tue, 4 Oct 2022 20:19:07 -0400 Subject: analyzer: revamp side-effects of call summaries [PR107072] With -fanalyzer-call-summaries the analyzer canl attempt to summarize the effects of some function calls at their call site, rather than simulate the call directly, which can avoid big slowdowns during analysis. Previously, this summarization was extremely simplistic: no attempt was made to update sm-state, and region_model::update_for_call_summary would simply set the return value of the function to UNKNOWN, and assume the function had no side effects. This patch implements less simplistic summarizations: it tracks each possible return enode from the called function, and attempts to generate a successor enode from the callsite for each that have compatible conditions, mapping state changes in the summary to state changes at the callsite. It also implements the beginnings of heuristics for generating user-facing descriptions of a summary e.g. "when 'foo' returns NULL" versus: "when 'foo' returns a heap-allocated buffer" This still has some bugs, but much more accurately tracks the effects of a call, and so is an improvement; it should only have an effect when -fanalyzer-call-summaries is enabled. As before, -fanalyzer-call-summaries is disabled by default in analyzer.opt (but enabled by default in the test suite). gcc/ChangeLog: PR analyzer/107072 * Makefile.in (ANALYZER_OBJS): Add analyzer/call-summary.o. gcc/analyzer/ChangeLog: PR analyzer/107072 * analyzer-logging.h: Include "diagnostic-core.h". * analyzer.h: Include "function.h". (class call_summary): New forward decl. (class call_summary_replay): New forward decl. (struct per_function_data): New forward decl. (struct interesting_t): New forward decl. (custom_edge_info::update_state): New vfunc. * call-info.cc (custom_edge_info::update_state): New. * call-summary.cc: New file. * call-summary.h: New file. * constraint-manager.cc: Include "analyzer/call-summary.h". (class replay_fact_visitor): New. (constraint_manager::replay_call_summary): New. * constraint-manager.h (constraint_manager::replay_call_summary): New. * engine.cc: Include "analyzer/call-summary.h". (exploded_node::on_stmt): Handle call summaries. (class call_summary_edge_info): New. (exploded_node::replay_call_summaries): New. (exploded_node::replay_call_summary): New. (per_function_data::~per_function_data): New. (per_function_data::add_call_summary): Move here from header and reimplement. (exploded_graph::process_node): Call update_state rather than update_model when handling bifurcation (viz_callgraph_node::dump_dot): Use a regular label rather than an HTML table; add summaries to dump. * exploded-graph.h: Include "alloc-pool.h", "fibonacci_heap.h", "supergraph.h", "sbitmap.h", "shortest-paths.h", "analyzer/sm.h", "analyzer/program-state.h", and "analyzer/diagnostic-manager.h". (exploded_node::replay_call_summaries): New decl. (exploded_node::replay_call_summary): New decl. (per_function_data::~per_function_data): New decl. (per_function_data::add_call_summary): Move implemention from header. (per_function_data::m_summaries): Update type of element. * known-function-manager.h: Include "analyzer/analyzer-logging.h". * program-point.h: Include "pretty-print.h" and "analyzer/call-string.h". * program-state.cc: Include "analyzer/call-summary.h". (sm_state_map::replay_call_summary): New. (program_state::replay_call_summary): New. * program-state.h (sm_state_map::replay_call_summary): New decl. (program_state::replay_call_summary): New decl. * region-model-manager.cc (region_model_manager::get_or_create_asm_output_svalue): New overload. * region-model-manager.h (region_model_manager::get_or_create_asm_output_svalue): New overload decl. * region-model.cc: Include "analyzer/call-summary.h". (region_model::maybe_update_for_edge): Remove call to region_model::update_for_call_summary on SUPEREDGE_INTRAPROCEDURAL_CALL. (region_model::update_for_call_summary): Delete. (region_model::replay_call_summary): New. * region-model.h (region_model::replay_call_summary): New decl. (region_model::update_for_call_summary): Delete decl. * store.cc: Include "analyzer/call-summary.h". (store::replay_call_summary): New. (store::replay_call_summary_cluster): New. * store.h: Include "tristate.h". (is_a_helper ::test): New. (store::replay_call_summary): New decl. (store::replay_call_summary_cluster): New decl. * supergraph.cc (get_ultimate_function_for_cgraph_edge): Remove "static" from decl. (supergraph_call_edge): Make stmt param const. * supergraph.h: Include "ordered-hash-map.h", "cfg.h", "basic-block.h", "gimple.h", "gimple-iterator.h", and "digraph.h". (supergraph_call_edge): Make stmt param const. (get_ultimate_function_for_cgraph_edge): New decl. * svalue.cc (compound_svalue::compound_svalue): Assert that we're not nesting compound_svalues. * svalue.h: Include "json.h", "analyzer/store.h", and "analyzer/program-point.h". (asm_output_svalue::get_num_outputs): New accessor. gcc/testsuite/ChangeLog: PR analyzer/107072 * gcc.dg/analyzer/call-summaries-2.c: New test. * gcc.dg/analyzer/call-summaries-3.c: New test. * gcc.dg/analyzer/call-summaries-asm-x86.c: New test. * gcc.dg/analyzer/call-summaries-malloc.c: New test. * gcc.dg/analyzer/call-summaries-pr107072.c: New test. Signed-off-by: David Malcolm --- gcc/analyzer/analyzer-logging.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'gcc/analyzer/analyzer-logging.h') diff --git a/gcc/analyzer/analyzer-logging.h b/gcc/analyzer/analyzer-logging.h index ef14b29..71b540c 100644 --- a/gcc/analyzer/analyzer-logging.h +++ b/gcc/analyzer/analyzer-logging.h @@ -23,6 +23,8 @@ along with GCC; see the file COPYING3. If not see #ifndef ANALYZER_LOGGING_H #define ANALYZER_LOGGING_H +#include "diagnostic-core.h" + namespace ana { /* A logger encapsulates a logging stream: a way to send -- cgit v1.1