From: Richard Biener Date: Wed, 20 Sep 2023 06:40:34 +0000 (+0200) Subject: tree-optimization/111489 - turn uninit limits to params X-Git-Tag: basepoints/gcc-15~5969 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b8a2a12464d25c45a51c14a025e8e2d3ca8ebeb0;p=thirdparty%2Fgcc.git tree-optimization/111489 - turn uninit limits to params The following turns MAX_NUM_CHAINS and MAX_CHAIN_LEN to params which allows to experiment with raising them. For the testcase in PR111489 raising MAX_CHAIN_LEN from 5 to 8 avoids the bogus diagnostics at -O2, at -O3 we need a MAX_CHAIN_LEN of 6. PR tree-optimization/111489 * doc/invoke.texi (--param uninit-max-chain-len): Document. (--param uninit-max-num-chains): Likewise. * params.opt (-param=uninit-max-chain-len=): New. (-param=uninit-max-num-chains=): Likewise. * gimple-predicate-analysis.cc (MAX_NUM_CHAINS): Define to param_uninit_max_num_chains. (MAX_CHAIN_LEN): Define to param_uninit_max_chain_len. (uninit_analysis::init_use_preds): Avoid VLA. (uninit_analysis::init_from_phi_def): Likewise. (compute_control_dep_chain): Avoid using MAX_CHAIN_LEN in template parameter. --- diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 09b2b92ad848..ba7984bcb7ec 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -16348,6 +16348,13 @@ crossing a loop backedge when comparing to Maximum number of nested calls to search for control dependencies during uninitialized variable analysis. +@item uninit-max-chain-len +Maximum number of predicates anded for each predicate ored in the normalized +predicate chain. + +@item uninit-max-num-chains +Maximum number of predicates ored in the normalized predicate chain. + @item sched-autopref-queue-depth Hardware autoprefetcher scheduler model control flag. Number of lookahead cycles the model looks into; at ' diff --git a/gcc/gimple-predicate-analysis.cc b/gcc/gimple-predicate-analysis.cc index 373163ba9c80..ad2c35524ce1 100644 --- a/gcc/gimple-predicate-analysis.cc +++ b/gcc/gimple-predicate-analysis.cc @@ -50,8 +50,8 @@ /* In our predicate normal form we have MAX_NUM_CHAINS or predicates and in those MAX_CHAIN_LEN (inverted) and predicates. */ -#define MAX_NUM_CHAINS 8 -#define MAX_CHAIN_LEN 5 +#define MAX_NUM_CHAINS (unsigned)param_uninit_max_num_chains +#define MAX_CHAIN_LEN (unsigned)param_uninit_max_chain_len /* Return true if X1 is the negation of X2. */ @@ -1163,11 +1163,12 @@ compute_control_dep_chain (basic_block dom_bb, const_basic_block dep_bb, vec cd_chains[], unsigned *num_chains, unsigned in_region = 0) { - auto_vec cur_cd_chain; + auto_vec cur_cd_chain; unsigned num_calls = 0; unsigned depth = 0; bool complete_p = true; /* Walk the post-dominator chain. */ + cur_cd_chain.reserve (MAX_CHAIN_LEN + 1); compute_control_dep_chain_pdom (dom_bb, dep_bb, NULL, cd_chains, num_chains, cur_cd_chain, &num_calls, in_region, depth, &complete_p); @@ -2035,7 +2036,7 @@ uninit_analysis::init_use_preds (predicate &use_preds, basic_block def_bb, are logical conjunctions. Together, the DEP_CHAINS vector is used below to initialize an OR expression of the conjunctions. */ unsigned num_chains = 0; - auto_vec dep_chains[MAX_NUM_CHAINS]; + auto_vec *dep_chains = new auto_vec[MAX_NUM_CHAINS]; if (!dfs_mark_dominating_region (use_bb, cd_root, in_region, region) || !compute_control_dep_chain (cd_root, use_bb, dep_chains, &num_chains, @@ -2060,6 +2061,7 @@ uninit_analysis::init_use_preds (predicate &use_preds, basic_block def_bb, Each OR subexpression is represented by one element of DEP_CHAINS, where each element consists of a series of AND subexpressions. */ use_preds.init_from_control_deps (dep_chains, num_chains, true); + delete[] dep_chains; return !use_preds.is_empty (); } @@ -2144,7 +2146,7 @@ uninit_analysis::init_from_phi_def (gphi *phi) break; unsigned num_chains = 0; - auto_vec dep_chains[MAX_NUM_CHAINS]; + auto_vec *dep_chains = new auto_vec[MAX_NUM_CHAINS]; for (unsigned i = 0; i < nedges; i++) { edge e = def_edges[i]; @@ -2175,6 +2177,7 @@ uninit_analysis::init_from_phi_def (gphi *phi) which the PHI operands are defined to values for which M_EVAL is false. */ m_phi_def_preds.init_from_control_deps (dep_chains, num_chains, false); + delete[] dep_chains; return !m_phi_def_preds.is_empty (); } diff --git a/gcc/params.opt b/gcc/params.opt index 70cfb495e3a9..a67778e456b5 100644 --- a/gcc/params.opt +++ b/gcc/params.opt @@ -1106,6 +1106,15 @@ Emit instrumentation calls to __tsan_func_entry() and __tsan_func_exit(). Common Joined UInteger Var(param_uninit_control_dep_attempts) Init(1000) IntegerRange(1, 65536) Param Optimization Maximum number of nested calls to search for control dependencies during uninitialized variable analysis. +-param=uninit-max-chain-len= +Common Joined UInteger Var(param_uninit_max_chain_len) Init(5) IntegerRange(1, 128) Param Optimization +Maximum number of predicates anded for each predicate ored in the normalized +predicate chain. + +-param=uninit-max-num-chains= +Common Joined UInteger Var(param_uninit_max_num_chains) Init(8) IntegerRange(1, 128) Param Optimization +Maximum number of predicates ored in the normalized predicate chain. + -param=uninlined-function-insns= Common Joined UInteger Var(param_uninlined_function_insns) Init(2) Optimization IntegerRange(0, 1000000) Param Instruction accounted for function prologue, epilogue and other overhead.