/* Global, SSA-based optimizations using mathematical identities.
Copyright (C) 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
-
+
This file is part of GCC.
-
+
GCC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any
later version.
-
+
GCC is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
-
+
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
recip_def = make_rename_temp (type, "reciptmp");
new_stmt = gimple_build_assign_with_ops (RDIV_EXPR, recip_def,
build_one_cst (type), def);
-
+
if (occ->bb_has_division)
{
/* Case 1: insert before an existing division. */
count++;
}
}
-
+
/* Do the expensive part only if we can hope to optimize something. */
threshold = targetm.min_divisions_for_recip_mul (TYPE_MODE (TREE_TYPE (def)));
if (count >= threshold)
|| DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD))
{
enum built_in_function code;
- bool md_code;
+ bool md_code, fail;
+ imm_use_iterator ui;
+ use_operand_p use_p;
code = DECL_FUNCTION_CODE (fndecl);
md_code = DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD;
if (!fndecl)
continue;
+ /* Check that all uses of the SSA name are divisions,
+ otherwise replacing the defining statement will do
+ the wrong thing. */
+ fail = false;
+ FOR_EACH_IMM_USE_FAST (use_p, ui, arg1)
+ {
+ gimple stmt2 = USE_STMT (use_p);
+ if (is_gimple_debug (stmt2))
+ continue;
+ if (!is_gimple_assign (stmt2)
+ || gimple_assign_rhs_code (stmt2) != RDIV_EXPR
+ || gimple_assign_rhs1 (stmt2) == arg1
+ || gimple_assign_rhs2 (stmt2) != arg1)
+ {
+ fail = true;
+ break;
+ }
+ }
+ if (fail)
+ continue;
+
+ gimple_replace_lhs (stmt1, arg1);
gimple_call_set_fndecl (stmt1, fndecl);
update_stmt (stmt1);
- gimple_assign_set_rhs_code (stmt, MULT_EXPR);
- fold_stmt_inplace (stmt);
- update_stmt (stmt);
+ FOR_EACH_IMM_USE_STMT (stmt, ui, arg1)
+ {
+ gimple_assign_set_rhs_code (stmt, MULT_EXPR);
+ fold_stmt_inplace (stmt);
+ update_stmt (stmt);
+ }
}
}
}
gsi = gsi_for_stmt (use_stmt);
gsi_insert_after (&gsi, stmt, GSI_SAME_STMT);
- gsi_remove (&gsi, true);
+ gsi_remove (&gsi, true);
}
VEC_free(gimple, heap, stmts);
}
};
-/* Find all expressions in the form of sqrt(a/b) and
- convert them to rsqrt(b/a). */
-
-static unsigned int
-execute_convert_to_rsqrt (void)
-{
- basic_block bb;
-
- FOR_EACH_BB (bb)
- {
- gimple_stmt_iterator gsi;
-
- for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
- {
- gimple stmt = gsi_stmt (gsi);
- tree fndecl;
-
- if (is_gimple_call (stmt)
- && gimple_call_lhs (stmt)
- && (fndecl = gimple_call_fndecl (stmt))
- && (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
- || DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD))
- {
- enum built_in_function code;
- bool md_code;
- tree arg1;
- gimple stmt1;
-
- code = DECL_FUNCTION_CODE (fndecl);
- md_code = DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_MD;
-
- fndecl = targetm.builtin_reciprocal (code, md_code, true);
- if (!fndecl)
- continue;
-
- arg1 = gimple_call_arg (stmt, 0);
-
- if (TREE_CODE (arg1) != SSA_NAME)
- continue;
-
- stmt1 = SSA_NAME_DEF_STMT (arg1);
-
- if (is_gimple_assign (stmt1)
- && gimple_assign_rhs_code (stmt1) == RDIV_EXPR)
- {
- tree arg10, arg11;
-
- arg10 = gimple_assign_rhs1 (stmt1);
- arg11 = gimple_assign_rhs2 (stmt1);
-
- /* Swap operands of RDIV_EXPR. */
- gimple_assign_set_rhs1 (stmt1, arg11);
- gimple_assign_set_rhs2 (stmt1, arg10);
- fold_stmt_inplace (stmt1);
- update_stmt (stmt1);
-
- gimple_call_set_fndecl (stmt, fndecl);
- update_stmt (stmt);
- }
- }
- }
- }
-
- return 0;
-}
-
-static bool
-gate_convert_to_rsqrt (void)
-{
- return flag_unsafe_math_optimizations && optimize;
-}
-
-struct gimple_opt_pass pass_convert_to_rsqrt =
-{
- {
- GIMPLE_PASS,
- "rsqrt", /* name */
- gate_convert_to_rsqrt, /* gate */
- execute_convert_to_rsqrt, /* execute */
- NULL, /* sub */
- NULL, /* next */
- 0, /* static_pass_number */
- TV_NONE, /* tv_id */
- PROP_ssa, /* properties_required */
- 0, /* properties_provided */
- 0, /* properties_destroyed */
- 0, /* todo_flags_start */
- TODO_dump_func | TODO_update_ssa | TODO_verify_ssa
- | TODO_verify_stmts /* todo_flags_finish */
- }
-};
-
/* A symbolic number is used to detect byte permutation and selection
patterns. Therefore the field N contains an artificial number
consisting of byte size markers:
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