From: Bin Cheng Date: Fri, 15 Aug 2014 02:42:33 +0000 (+0000) Subject: tree-ssa-loop-ivopts.c (ivopts_data): New field name_expansion_cache. X-Git-Tag: releases/gcc-5.1.0~5471 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3230c614e7d67dee0eb5e20bb6c88bbe8393bb3e;p=thirdparty%2Fgcc.git tree-ssa-loop-ivopts.c (ivopts_data): New field name_expansion_cache. * tree-ssa-loop-ivopts.c (ivopts_data): New field name_expansion_cache. (tree_ssa_iv_optimize_init): Initialize name_expansion_cache. (tree_ssa_iv_optimize_finalize): Free name_expansion_cache. (strip_wrap_conserving_type_conversions, expr_equal_p): Delete. (difference_cannot_overflow_p): New parameter. Use affine expansion for equality check. (iv_elimination_compare_lt): Pass new argument. testsuite/ChangeLog * gcc.dg/tree-ssa/ivopts-lt-2.c: New test. From-SVN: r213997 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 88196b29900e..f1b17338e7e6 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,14 @@ +2014-08-15 Bin Cheng + + * tree-ssa-loop-ivopts.c (ivopts_data): New field + name_expansion_cache. + (tree_ssa_iv_optimize_init): Initialize name_expansion_cache. + (tree_ssa_iv_optimize_finalize): Free name_expansion_cache. + (strip_wrap_conserving_type_conversions, expr_equal_p): Delete. + (difference_cannot_overflow_p): New parameter. Use affine + expansion for equality check. + (iv_elimination_compare_lt): Pass new argument. + 2014-08-14 DJ Delorie * config/rl78/rl78-expand.md (umulqihi3): Disable for G10. diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 73a6ab835bc8..a55214702cb1 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2014-08-15 Bin Cheng + + * gcc.dg/tree-ssa/ivopts-lt-2.c: New test. + 2014-08-14 Jan Hubicka PR tree-optimization/62091 diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ivopts-lt-2.c b/gcc/testsuite/gcc.dg/tree-ssa/ivopts-lt-2.c new file mode 100644 index 000000000000..177e0689248c --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ivopts-lt-2.c @@ -0,0 +1,20 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-ivopts" } */ + +void +f1 (int *p, unsigned int i) +{ + p += i; + do + { + *p = 0; + p += 1; + i++; + } + while (i < 100); +} + +/* { dg-final { scan-tree-dump-times "PHI" 1 "ivopts" } } */ +/* { dg-final { scan-tree-dump-times "PHI *name_expansion_cache; + /* The maximum invariant id. */ unsigned max_inv_id; @@ -876,6 +879,7 @@ tree_ssa_iv_optimize_init (struct ivopts_data *data) data->iv_candidates.create (20); data->inv_expr_tab = new hash_table (10); data->inv_expr_id = 0; + data->name_expansion_cache = NULL; decl_rtl_to_reset.create (20); } @@ -4462,75 +4466,20 @@ iv_elimination_compare (struct ivopts_data *data, struct iv_use *use) return (exit->flags & EDGE_TRUE_VALUE ? EQ_EXPR : NE_EXPR); } -static tree -strip_wrap_conserving_type_conversions (tree exp) -{ - while (tree_ssa_useless_type_conversion (exp) - && (nowrap_type_p (TREE_TYPE (exp)) - == nowrap_type_p (TREE_TYPE (TREE_OPERAND (exp, 0))))) - exp = TREE_OPERAND (exp, 0); - return exp; -} - -/* Walk the SSA form and check whether E == WHAT. Fairly simplistic, we - check for an exact match. */ - -static bool -expr_equal_p (tree e, tree what) -{ - gimple stmt; - enum tree_code code; - - e = strip_wrap_conserving_type_conversions (e); - what = strip_wrap_conserving_type_conversions (what); - - code = TREE_CODE (what); - if (TREE_TYPE (e) != TREE_TYPE (what)) - return false; - - if (operand_equal_p (e, what, 0)) - return true; - - if (TREE_CODE (e) != SSA_NAME) - return false; - - stmt = SSA_NAME_DEF_STMT (e); - if (gimple_code (stmt) != GIMPLE_ASSIGN - || gimple_assign_rhs_code (stmt) != code) - return false; - - switch (get_gimple_rhs_class (code)) - { - case GIMPLE_BINARY_RHS: - if (!expr_equal_p (gimple_assign_rhs2 (stmt), TREE_OPERAND (what, 1))) - return false; - /* Fallthru. */ - - case GIMPLE_UNARY_RHS: - case GIMPLE_SINGLE_RHS: - return expr_equal_p (gimple_assign_rhs1 (stmt), TREE_OPERAND (what, 0)); - default: - return false; - } -} - /* Returns true if we can prove that BASE - OFFSET does not overflow. For now, we only detect the situation that BASE = SOMETHING + OFFSET, where the calculation is performed in non-wrapping type. TODO: More generally, we could test for the situation that BASE = SOMETHING + OFFSET' and OFFSET is between OFFSET' and zero. - This would require knowing the sign of OFFSET. - - Also, we only look for the first addition in the computation of BASE. - More complex analysis would be better, but introducing it just for - this optimization seems like an overkill. */ + This would require knowing the sign of OFFSET. */ static bool -difference_cannot_overflow_p (tree base, tree offset) +difference_cannot_overflow_p (struct ivopts_data *data, tree base, tree offset) { enum tree_code code; tree e1, e2; + aff_tree aff_e1, aff_e2, aff_offset; if (!nowrap_type_p (TREE_TYPE (base))) return false; @@ -4560,13 +4509,27 @@ difference_cannot_overflow_p (tree base, tree offset) e2 = TREE_OPERAND (base, 1); } - /* TODO: deeper inspection may be necessary to prove the equality. */ + /* Use affine expansion as deeper inspection to prove the equality. */ + tree_to_aff_combination_expand (e2, TREE_TYPE (e2), + &aff_e2, &data->name_expansion_cache); + tree_to_aff_combination_expand (offset, TREE_TYPE (offset), + &aff_offset, &data->name_expansion_cache); + aff_combination_scale (&aff_offset, -1); switch (code) { case PLUS_EXPR: - return expr_equal_p (e1, offset) || expr_equal_p (e2, offset); + aff_combination_add (&aff_e2, &aff_offset); + if (aff_combination_zero_p (&aff_e2)) + return true; + + tree_to_aff_combination_expand (e1, TREE_TYPE (e1), + &aff_e1, &data->name_expansion_cache); + aff_combination_add (&aff_e1, &aff_offset); + return aff_combination_zero_p (&aff_e1); + case POINTER_PLUS_EXPR: - return expr_equal_p (e2, offset); + aff_combination_add (&aff_e2, &aff_offset); + return aff_combination_zero_p (&aff_e2); default: return false; @@ -4690,7 +4653,7 @@ iv_elimination_compare_lt (struct ivopts_data *data, offset = fold_build2 (MULT_EXPR, TREE_TYPE (cand->iv->step), cand->iv->step, fold_convert (TREE_TYPE (cand->iv->step), a)); - if (!difference_cannot_overflow_p (cand->iv->base, offset)) + if (!difference_cannot_overflow_p (data, cand->iv->base, offset)) return false; /* Determine the new comparison operator. */ @@ -6815,6 +6778,7 @@ tree_ssa_iv_optimize_finalize (struct ivopts_data *data) data->iv_candidates.release (); delete data->inv_expr_tab; data->inv_expr_tab = NULL; + free_affine_expand_cache (&data->name_expansion_cache); } /* Returns true if the loop body BODY includes any function calls. */