===================================================================
@@ -462,6 +462,7 @@
cpu_type=sh
need_64bit_hwint=yes
extra_options="${extra_options} fused-madd.opt"
+ extra_objs="${extra_objs} ifcvt_sh.o"
;;
v850*-*-*)
cpu_type=v850
===================================================================
@@ -53,6 +53,9 @@
#include "alloc-pool.h"
#include "tm-constrs.h"
#include "opts.h"
+#include "tree-pass.h"
+#include "pass_manager.h"
+#include "context.h"
#include <sstream>
#include <vector>
@@ -311,6 +314,7 @@
static void sh_canonicalize_comparison (int *, rtx *, rtx *, bool);
static void sh_canonicalize_comparison (enum rtx_code&, rtx&, rtx&,
enum machine_mode, bool);
+static bool sh_fixed_condition_code_regs (unsigned int* p1, unsigned int* p2);
static void sh_init_sync_libfuncs (void) ATTRIBUTE_UNUSED;
@@ -587,6 +591,9 @@
#undef TARGET_CANONICALIZE_COMPARISON
#define TARGET_CANONICALIZE_COMPARISON sh_canonicalize_comparison
+#undef TARGET_FIXED_CONDITION_CODE_REGS
+#define TARGET_FIXED_CONDITION_CODE_REGS sh_fixed_condition_code_regs
+
/* Machine-specific symbol_ref flags. */
#define SYMBOL_FLAG_FUNCVEC_FUNCTION (SYMBOL_FLAG_MACH_DEP << 0)
@@ -710,6 +717,34 @@
#undef err_ret
}
+/* Register SH specific RTL passes. */
+extern opt_pass* make_pass_ifcvt_sh (gcc::context* ctx, bool split_insns,
+ const char* name);
+static void
+register_sh_passes (void)
+{
+ if (!TARGET_SH1)
+ return;
+
+/* Running the ifcvt_sh pass after ce1 generates better code when
+ comparisons are combined and reg-reg moves are introduced, because
+ reg-reg moves will be eliminated afterwards. However, there are quite
+ some cases where combine will be unable to fold comparison related insns,
+ thus for now don't do it.
+ register_pass (make_pass_ifcvt_sh (g, false, "ifcvt1_sh"),
+ PASS_POS_INSERT_AFTER, "ce1", 1);
+*/
+
+ /* Run ifcvt_sh pass after combine but before register allocation. */
+ register_pass (make_pass_ifcvt_sh (g, true, "ifcvt2_sh"),
+ PASS_POS_INSERT_AFTER, "split1", 1);
+
+ /* Run ifcvt_sh pass after register allocation and basic block reordering
+ as this sometimes creates new opportunities. */
+ register_pass (make_pass_ifcvt_sh (g, true, "ifcvt3_sh"),
+ PASS_POS_INSERT_AFTER, "split4", 1);
+}
+
/* Implement TARGET_OPTION_OVERRIDE macro. Validate and override
various options, and do some machine dependent initialization. */
static void
@@ -1022,6 +1057,8 @@
target CPU. */
selected_atomic_model_
= parse_validate_atomic_model_option (sh_atomic_model_str);
+
+ register_sh_passes ();
}
/* Print the operand address in x to the stream. */
@@ -1908,7 +1945,7 @@
static void
sh_canonicalize_comparison (enum rtx_code& cmp, rtx& op0, rtx& op1,
enum machine_mode mode,
- bool op0_preserve_value ATTRIBUTE_UNUSED)
+ bool op0_preserve_value)
{
/* When invoked from within the combine pass the mode is not specified,
so try to get it from one of the operands. */
@@ -1928,6 +1965,9 @@
// Make sure that the constant operand is the second operand.
if (CONST_INT_P (op0) && !CONST_INT_P (op1))
{
+ if (op0_preserve_value)
+ return;
+
std::swap (op0, op1);
cmp = swap_condition (cmp);
}
@@ -2016,6 +2056,14 @@
*code = (int)tmp_code;
}
+bool
+sh_fixed_condition_code_regs (unsigned int* p1, unsigned int* p2)
+{
+ *p1 = T_REG;
+ *p2 = INVALID_REGNUM;
+ return true;
+}
+
enum rtx_code
prepare_cbranch_operands (rtx *operands, enum machine_mode mode,
enum rtx_code comparison)
===================================================================
@@ -8419,89 +8419,32 @@
return output_branch (sh_eval_treg_value (operands[1]), insn, operands);
}
"&& 1"
- [(set (pc) (if_then_else (eq (reg:SI T_REG) (match_dup 2))
- (label_ref (match_dup 0))
- (pc)))]
+ [(const_int 0)]
{
- /* Try to find missed test and branch combine opportunities which result
- in redundant T bit tests before conditional branches.
- This is done not only after combine (and before reload) but in every
- split pass, because some opportunities are formed also after combine.
- FIXME: Probably this would not be needed if CCmode was used
- together with TARGET_FIXED_CONDITION_CODE_REGS. */
+ /* Try to canonicalize the branch condition if it is not one of:
+ (ne (reg:SI T_REG) (const_int 0))
+ (eq (reg:SI T_REG) (const_int 0))
- const int treg_value = sh_eval_treg_value (operands[1]);
- operands[2] = NULL_RTX;
+ Instead of splitting out a new insn, we modify the current insn's
+ operands as needed. This preserves things such as REG_DEAD notes. */
- /* Scan the insns backwards for an insn that sets the T bit by testing a
- reg against zero like:
- (set (reg T_REG) (eq (reg) (const_int 0))) */
- rtx testing_insn = NULL_RTX;
- rtx tested_reg = NULL_RTX;
+ if ((GET_CODE (operands[1]) == EQ || GET_CODE (operands[1]) == NE)
+ && REG_P (XEXP (operands[1], 0)) && REGNO (XEXP (operands[1], 0)) == T_REG
+ && XEXP (operands[1], 1) == const0_rtx)
+ DONE;
- set_of_reg s0 = sh_find_set_of_reg (get_t_reg_rtx (), curr_insn,
- prev_nonnote_insn_bb);
- if (s0.set_src != NULL_RTX
- && GET_CODE (s0.set_src) == EQ
- && REG_P (XEXP (s0.set_src, 0))
- && satisfies_constraint_Z (XEXP (s0.set_src, 1)))
- {
- testing_insn = s0.insn;
- tested_reg = XEXP (s0.set_src, 0);
- }
- else
- FAIL;
+ int branch_cond = sh_eval_treg_value (operands[1]);
+ rtx new_cond_rtx = NULL_RTX;
- /* Continue scanning the insns backwards and try to find the insn that
- sets the tested reg which we found above. If the reg is set by storing
- the T bit or the negated T bit we can eliminate the test insn before
- the branch. Notice that the branch condition has to be inverted if the
- test is eliminated. */
+ if (branch_cond == 0)
+ new_cond_rtx = gen_rtx_EQ (VOIDmode, get_t_reg_rtx (), const0_rtx);
+ else if (branch_cond == 1)
+ new_cond_rtx = gen_rtx_NE (VOIDmode, get_t_reg_rtx (), const0_rtx);
- /* If the T bit is used between the testing insn and the brach insn
- leave it alone. */
- if (reg_used_between_p (get_t_reg_rtx (), testing_insn, curr_insn))
- FAIL;
-
- while (true)
- {
- /* It's not safe to go beyond the current basic block after reload. */
- set_of_reg s1 = sh_find_set_of_reg (tested_reg, s0.insn,
- reload_completed
- ? prev_nonnote_insn_bb
- : prev_nonnote_insn);
- if (s1.set_src == NULL_RTX)
- break;
-
- if (t_reg_operand (s1.set_src, VOIDmode))
- operands[2] = GEN_INT (treg_value ^ 1);
- else if (negt_reg_operand (s1.set_src, VOIDmode))
- operands[2] = GEN_INT (treg_value);
- else if (REG_P (s1.set_src))
- {
- /* If it's a reg-reg copy follow the copied reg. This can
- happen e.g. when T bit store zero-extensions are
- eliminated. */
- tested_reg = s1.set_src;
- s0.insn = s1.insn;
- continue;
- }
-
- /* It's only safe to remove the testing insn if the T bit is not
- modified between the testing insn and the insn that stores the
- T bit. Notice that some T bit stores such as negc also modify
- the T bit. */
- if (modified_between_p (get_t_reg_rtx (), s1.insn, testing_insn)
- || modified_in_p (get_t_reg_rtx (), s1.insn))
- operands[2] = NULL_RTX;
-
- break;
- }
-
- if (operands[2] == NULL_RTX)
- FAIL;
-
- set_insn_deleted (testing_insn);
+ if (new_cond_rtx != NULL_RTX)
+ validate_change (curr_insn, &XEXP (XEXP (PATTERN (curr_insn), 1), 0),
+ new_cond_rtx, false);
+ DONE;
}
[(set_attr "type" "cbranch")])
@@ -11480,10 +11423,12 @@
;; multiple insns like:
;; movt Rn
;; tst Rn,Rn
+;; This requires an additional pseudo. The SH specific ifcvt_sh pass will
+;; look for this insn. Disallow using it if pseudos can't be created.
(define_insn_and_split "nott"
[(set (reg:SI T_REG)
- (xor:SI (match_operand:SI 0 "t_reg_operand" "") (const_int 1)))]
- "TARGET_SH1"
+ (xor:SI (match_operand:SI 0 "t_reg_operand") (const_int 1)))]
+ "TARGET_SH2A || (TARGET_SH1 && can_create_pseudo_p ())"
{
gcc_assert (TARGET_SH2A);
return "nott";
===================================================================
@@ -21,6 +21,10 @@
$(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) \
$(srcdir)/config/sh/sh-c.c
+ifcvt_sh.o: $(srcdir)/config/sh/ifcvt_sh.cc \
+ $(CONFIG_H) $(SYSTEM_H) $(TREE_H) $(TM_H) $(TM_P_H) coretypes.h
+ $(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) $<
+
DEFAULT_ENDIAN = $(word 1,$(TM_ENDIAN_CONFIG))
OTHER_ENDIAN = $(word 2,$(TM_ENDIAN_CONFIG))
===================================================================
@@ -0,0 +1,1489 @@
+/* An SH specific if-conversion RTL pass that tries to combine comparisons
+ and redundant condition code register stores across multiple basic blocks.
+ Copyright (C) 2013 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/>. */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "machmode.h"
+#include "basic-block.h"
+#include "df.h"
+#include "rtl.h"
+#include "insn-config.h"
+#include "insn-codes.h"
+#include "emit-rtl.h"
+#include "recog.h"
+#include "tree-pass.h"
+#include "target.h"
+#include "expr.h"
+
+#include <algorithm>
+#include <list>
+#include <vector>
+
+/*
+This pass tries to optimize for example this:
+ mov.l @(4,r4),r1
+ tst r1,r1
+ movt r1
+ tst r1,r1
+ bt/s .L5
+
+into something simpler:
+ mov.l @(4,r4),r1
+ tst r1,r1
+ bf/s .L5
+
+Such sequences can be identified by looking for conditional branches and
+checking whether the ccreg is set before the conditional branch
+by testing another register for != 0, which was set by a ccreg store.
+This can be optimized by eliminating the redundant comparison and
+inverting the branch condition. There can be multiple comparisons in
+different basic blocks that all end up in the redunant test insn before the
+conditional branch. Some example RTL ...
+
+Example 1)
+----------
+
+[bb 3]
+(set (reg:SI 147 t) (eq:SI (reg:SI 173) (const_int 0)))
+(set (reg:SI 167) (xor:SI (reg:SI 147 t) (const_int 1)))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 147 t) (eq:SI (reg:SI 177) (const_int 0)))
+(set (reg:SI 167) (reg:SI 147 t))
+-> bb 5
+
+[bb 5]
+(set (reg:SI 147 t) (eq:SI (reg:SI 167) (const_int 0)))
+(set (pc) (if_then_else (ne (reg:SI 147 t) (const_int 0))
+ (label_ref:SI 50) (pc)))
+
+In [bb 4] elimination of the comparison would require inversion of the branch
+condition and compensation of other BBs.
+Instead an inverting reg-move can be used:
+
+[bb 3]
+(set (reg:SI 167) (reg:SI 173))
+-> bb 5
+
+[BB 4]
+(set (reg:SI 167) (not:SI (reg:SI 177)))
+-> bb 5
+
+[bb 5]
+(set (reg:SI 147 t) (eq:SI (reg:SI 167) (const_int 0)))
+(set (pc) (if_then_else (ne (reg:SI 147 t) (const_int 0)))
+ (label_ref:SI 50) (pc)))
+
+
+Example 2)
+----------
+
+[bb 3]
+(set (reg:SI 147 t) (gt:SI (reg:SI 173) (reg:SI 175)))
+(set (reg:SI 167) (reg:SI 147 t))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 147 t) (gt:SI (reg:SI 177) (reg:SI 179)))
+(set (reg:SI 167) (reg:SI 147 t))
+-> bb 5
+
+[bb 5]
+(set (reg:SI 147 t) (eq:SI (reg:SI 167) (const_int 0)))
+(set (pc) (if_then_else (ne (reg:SI 147 t) (const_int 0))
+ (label_ref:SI 51) (pc)))
+
+The common comparison is factored out and the branch condition is inverted:
+
+[bb 3]
+(set (reg:SI 167) (reg:SI 173))
+(set (reg:SI 200) (reg:SI 175))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 167) (reg:SI 177))
+(set (reg:SI 200) (reg:SI 179))
+-> bb 5
+
+[bb 5]
+(set (reg:SI 147 t) (gt:SI (reg:SI 167) (reg:SI 200)))
+(set (pc) (if_then_else (eq (reg:SI 147 t) (const_int 0))
+ (label_ref:SI 51) (pc)))
+
+
+Example 3)
+----------
+
+[bb 3]
+(set (reg:SI 147 t) (gt:SI (reg:SI 173) (reg:SI 175)))
+(set (reg:SI 167) (reg:SI 147 t))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 147 t) (ge:SI (reg:SI 179) (reg:SI 177)))
+(set (reg:SI 167) (reg:SI 147 t))
+-> bb 5
+
+[bb 5]
+(set (reg:SI 147 t) (eq:SI (reg:SI 167) (const_int 0)))
+(set (pc) (if_then_else (ne (reg:SI 147 t) (const_int 0))
+ (label_ref:SI 51) (pc)))
+
+The T bit lifetime is extended and the branch condition is inverted:
+
+[bb 3]
+(set (reg:SI 147 t) (gt:SI (reg:SI 173) (reg:SI 175)))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 147 t) (ge:SI (reg:SI 179) (reg:SI 177)))
+-> bb 5
+
+[bb 5]
+(set (pc) (if_then_else (eq (reg:SI 147 t) (const_int 0))
+ (label_ref:SI 51) (pc)))
+
+
+Example 4)
+----------
+
+[bb 3]
+(set (reg:SI 147 t) (eq:SI (reg:SI 173) (const_int 5)))
+(set (reg:SI 167) (reg:SI 147 t))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 147 t) (eq:SI (reg:SI 176) (const_int 5)))
+(set (reg:SI 167) (xor:SI (reg:SI 147 t) (const_int 1)))
+-> bb 5
+
+[bb 5]
+(set (reg:SI 147 t) (eq:SI (reg:SI 167) (const_int 0)))
+(set (pc) (if_then_else (ne (reg:SI 147 t) (const_int 0))
+ (label_ref:SI 50) (pc)))
+
+In this case the comparisons are the same and could be combined, but the
+branch condition is different for [bb 3] and [bb 5]. Since the comparison
+is not a zero comparison, we can't negate one of the operands. The best thing
+we can do here is to eliminate the comparison before the cbranch and invert
+the ccreg in one of the BBs. On SH2A this will utilize the 'nott' instruction.
+
+[bb 3]
+(set (reg:SI 147 t) (eq:SI (reg:SI 173) (const_int 5)))
+-> bb 5
+
+[bb 4]
+(set (reg:SI 147 t) (eq:SI (reg:SI 176) (const_int 5)))
+(set (reg:SI 147 t) (xor:SI (reg:SI 147 t) (const_int 1)))
+-> bb 5
+
+[bb 5]
+(set (pc) (if_then_else (eq (reg:SI 147 t) (const_int 0)) // inverted
+ (label_ref:SI 50) (pc)))
+
+
+In order to handle cases such as above the RTL pass does the following:
+
+- Find the ccreg sets (comparisons) and ccreg stores
+ (inverting and non-inverting) in all related BBs.
+
+- If the comparison types in the BBs are all the same, try to combine the
+ comparisons in the BBs and replace the zero comparison before the cbranch
+ with the common comparison.
+
+ - If the cstores are the same, move the comparison before the cbranch
+ and replace the comparisons in the BBs with reg-reg copies to get the
+ operands in place (create new pseudo regs).
+
+ - If the cstores differ, try to apply the special case
+ (eq (reg) (const_int 0)) -> inverted = (not (reg)).
+ for the subordinate cstore types and eliminate the dominating ones.
+
+- If the comparison types in the BBs are not the same, or the first approach
+ doesn't work out for some reason, try to eliminate the comparison before the
+ cbranch by extending the lifetime of the ccreg by leaving the individual
+ comparisons but eliminating the cstores.
+ If the cstores are all the same this is straight forward.
+ If they're not, try to reverse the ccreg for the subordinate cstore type
+ and eliminate the dominating one.
+*/
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+// Helper functions
+
+#define log_msg(...)\
+ do { if (dump_file != NULL) fprintf (dump_file, __VA_ARGS__); } while (0)
+
+#define log_insn(i)\
+ do { if (dump_file != NULL) print_rtl_single (dump_file, (const_rtx)i); } while (0)
+
+#define log_rtx(r)\
+ do { if (dump_file != NULL) print_rtl (dump_file, (const_rtx)r); } while (0)
+
+#define log_return(retval, ...)\
+ do { if (dump_file != NULL) fprintf (dump_file, __VA_ARGS__); \
+ return retval; } while (0)
+
+#define log_return_void(...)\
+ do { if (dump_file != NULL) fprintf (dump_file, __VA_ARGS__); \
+ return; } while (0)
+
+struct set_of_reg
+{
+ // The insn where the search stopped or NULL_RTX.
+ rtx insn;
+
+ // The set rtx of the specified reg if found, NULL_RTX otherwise.
+ // Notice that the set rtx can also be in a parallel.
+ const_rtx set_rtx;
+
+ // The set source operand rtx if found, NULL_RTX otherwise.
+ rtx
+ set_src (void) const
+ {
+ return set_rtx == NULL_RTX ? NULL_RTX : XEXP (set_rtx, 1);
+ }
+
+ // The set destination operand rtx if found, NULL_RTX otherwise.
+ rtx
+ set_dst (void) const
+ {
+ return set_rtx == NULL_RTX ? NULL_RTX : XEXP (set_rtx, 0);
+ }
+
+ bool
+ empty (void) const
+ {
+ return insn == NULL_RTX || set_rtx == NULL_RTX;
+ }
+};
+
+// Given a reg rtx and a start insn find the insn (in the same basic block)
+// that sets the reg.
+static set_of_reg
+find_set_of_reg_bb (rtx reg, rtx insn)
+{
+ set_of_reg result = { insn, NULL_RTX };
+
+ if (!REG_P (reg) || insn == NULL_RTX)
+ return result;
+
+ for (result.insn = insn; result.insn != NULL_RTX;
+ result.insn = prev_nonnote_insn_bb (result.insn))
+ {
+ if (BARRIER_P (result.insn))
+ return result;
+ if (!NONJUMP_INSN_P (result.insn))
+ continue;
+ if (reg_set_p (reg, result.insn))
+ {
+ result.set_rtx = set_of (reg, result.insn);
+ if (result.set_rtx == NULL_RTX || GET_CODE (result.set_rtx) != SET)
+ result.set_rtx = NULL_RTX;
+ return result;
+ }
+ }
+
+ return result;
+}
+
+static bool
+reg_dead_after_insn (const_rtx reg, const_rtx insn)
+{
+ return find_regno_note (insn, REG_DEAD, REGNO (reg)) != NULL_RTX;
+}
+
+static bool
+reg_unused_after_insn (const_rtx reg, const_rtx insn)
+{
+ return find_regno_note (insn, REG_UNUSED, REGNO (reg)) != NULL_RTX;
+}
+
+// Check whether the two specified basic blocks are adjacent, i.e. there's no
+// other basic block in between them.
+static bool
+is_adjacent_bb (basic_block a, basic_block b)
+{
+ basic_block bb0[] = { a, b };
+ basic_block bb1[] = { b, a };
+
+ for (int i = 0; i < 2; ++i)
+ for (edge_iterator ei = ei_start (bb0[i]->succs);
+ !ei_end_p (ei); ei_next (&ei))
+ if (ei_edge (ei)->dest == bb1[i])
+ return true;
+
+ return false;
+}
+
+// Internal function of trace_reg_uses.
+static void
+trace_reg_uses_1 (rtx reg, rtx start_insn, basic_block bb, int& count,
+ std::vector<basic_block>& visited_bb, rtx abort_at_insn)
+{
+ if (bb == NULL)
+ return;
+
+ if (std::find (visited_bb.begin (), visited_bb.end (), bb)
+ != visited_bb.end ())
+ log_return_void ("[bb %d] already visited\n", bb->index);
+
+ visited_bb.push_back (bb);
+
+ if (BB_END (bb) == NULL_RTX)
+ log_return_void ("[bb %d] BB_END is null\n", bb->index);
+
+ if (start_insn == NULL_RTX)
+ log_return_void ("[bb %d] start_insn is null\n", bb->index);
+
+ rtx end_insn = NEXT_INSN (BB_END (bb));
+ if (end_insn == NULL_RTX)
+ log_return_void ("[bb %d] end_insn is null\n", bb->index);
+
+ for (rtx i = NEXT_INSN (start_insn); i != end_insn; i = NEXT_INSN (i))
+ {
+ if (INSN_P (i))
+ {
+ if (NONDEBUG_INSN_P (i)
+ && (reg_overlap_mentioned_p (reg, PATTERN (i))
+ || (CALL_P (i) && find_reg_fusage (i, USE, reg))))
+ {
+ log_msg ("found use in [bb %d] at insn:\n", bb->index);
+ log_insn (i);
+ log_msg ("\n");
+ count += 1;
+ }
+
+ // Stop following this BB if the reg is set or dies along the way.
+ if (reg_set_p (reg, i) || reg_dead_after_insn (reg, i))
+ return;
+ }
+
+ if (abort_at_insn != NULL_RTX && abort_at_insn == i)
+ return;
+ }
+
+ for (edge_iterator ei = ei_start (bb->succs); !ei_end_p (ei); ei_next (&ei))
+ {
+ basic_block succ_bb = ei_edge (ei)->dest;
+ trace_reg_uses_1 (reg, BB_HEAD (succ_bb), succ_bb, count, visited_bb,
+ abort_at_insn);
+ }
+}
+
+// Trace uses of the specified reg in all basic blocks that are reachable from
+// the specified insn. If 'abort_at_insn' is not null, abort the trace at
+// that insn. If the insn 'abort_at_insn' uses the specified reg, it is also
+// counted.
+static int
+trace_reg_uses (rtx reg, rtx start_insn, rtx abort_at_insn)
+{
+ log_msg ("\ntrace_reg_uses\nreg = ");
+ log_rtx (reg);
+ log_msg ("\nstart_insn = ");
+ log_insn (start_insn);
+
+ int count = 0;
+ std::vector<basic_block> visited_bb;
+ visited_bb.reserve (32);
+
+ trace_reg_uses_1 (reg, start_insn, BLOCK_FOR_INSN (start_insn),
+ count, visited_bb, abort_at_insn);
+ return count;
+}
+
+// FIXME: Remove dependency on SH predicate function somehow.
+extern int t_reg_operand (rtx, machine_mode);
+extern int negt_reg_operand (rtx, machine_mode);
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+// RTL pass class
+
+class ifcvt_sh : public rtl_opt_pass
+{
+public:
+ ifcvt_sh (gcc::context* ctx, bool split_insns, const char* name);
+ virtual ~ifcvt_sh (void);
+ virtual bool gate (void);
+ virtual unsigned int execute (void);
+
+private:
+ // Type of ccreg store that is supported.
+ enum cstore_type_t
+ {
+ cstore_normal = 0,
+ cstore_inverted = 1,
+ cstore_unknown = -1
+ };
+
+ // Type of branch condition that is supported.
+ enum branch_condition_type_t
+ {
+ branch_if_true = 1,
+ branch_if_false = 0,
+ unknown_branch_condition = -1
+ };
+
+ // For each basic block there can be a trace entry which consists of an
+ // insn that sets the ccreg (usually a comparison) and a ccreg store.
+ struct bb_entry
+ {
+ basic_block bb;
+ set_of_reg setcc;
+ set_of_reg cstore;
+ cstore_type_t cstore_type;
+ std::vector<set_of_reg> cstore_reg_reg_copies;
+
+ bb_entry (basic_block b)
+ : bb (b), setcc (), cstore (), cstore_type (cstore_unknown) { }
+
+ rtx comparison_rtx (void) const { return setcc.set_src (); }
+ };
+
+ // A ccreg trace for a conditional branch.
+ struct cbranch_trace
+ {
+ rtx cbranch_insn;
+ branch_condition_type_t cbranch_type;
+
+ // The comparison against zero right before the conditional branch.
+ set_of_reg setcc;
+
+ // All BBs that are related to the cbranch. The last BB in the list is
+ // the BB of the cbranch itself and might be empty.
+ std::list<bb_entry> bb_entries;
+
+ cbranch_trace (rtx insn)
+ : cbranch_insn (insn),
+ cbranch_type (unknown_branch_condition),
+ setcc ()
+ {
+ }
+
+ basic_block bb (void) const { return BLOCK_FOR_INSN (cbranch_insn); }
+
+ rtx
+ branch_condition_rtx (void) const
+ {
+ rtx x = pc_set (cbranch_insn);
+ return x == NULL_RTX ? NULL_RTX : XEXP (XEXP (x, 1), 0);
+ }
+
+ bool
+ can_invert_condition (void) const
+ {
+ // The branch condition can be inverted safely only if the condition
+ // reg is dead after the cbranch.
+ return reg_dead_after_insn (XEXP (branch_condition_rtx (), 0),
+ cbranch_insn);
+ }
+ };
+
+ static const pass_data default_pass_data;
+
+ // Tells whether modified or newly added insns are to be split at the end
+ // of the pass.
+ const bool split_insns_;
+
+ // Captured dump_file != NULL.
+ bool en_logging_;
+
+ // rtx of the ccreg that is obtained from the target.
+ rtx ccreg_;
+
+ // Newly added or modified insns.
+ std::vector<rtx> touched_insns_;
+
+ // Given an rtx determine whether it's a comparison with a constant zero.
+ static bool is_cmp_eq_zero (const_rtx i);
+
+ // Update the stored mode of the ccreg from the given branch condition rtx.
+ void update_ccreg_mode (const_rtx cond);
+
+ // Given an rtx, figure out the branch condition, assuming that it is
+ // in canonical form:
+ // (ne (reg) (const_int 0))
+ // (eq (reg) (const_int 0))
+ branch_condition_type_t branch_condition_type (const_rtx cond) const;
+
+ // Return true if the specified rtx is either a normal ccreg or
+ // a negated form of the ccreg.
+ bool is_normal_ccreg (const_rtx x) const;
+ bool is_inverted_ccreg (const_rtx x) const;
+
+ // Given a reg rtx and a start insn rtx, try to find the insn in the same
+ // basic block that sets the specified reg.
+ // Return how the search ended and the insn where it stopped or NULL_RTX.
+ enum record_return_t
+ {
+ set_found,
+ set_not_found,
+ other_set_found
+ };
+ record_return_t record_set_of_reg (rtx reg, rtx start_insn, bb_entry& e);
+
+ // Tells whether the cbranch insn of the specified bb_entry can be removed
+ // safely without triggering any side effects.
+ bool can_remove_cstore (const bb_entry& e,
+ const cbranch_trace& trace) const;
+
+ // Tells whether the setcc insn of the specified bb_entry can be removed
+ // safely without triggering any side effects.
+ bool can_remove_comparison (const bb_entry& e,
+ const cbranch_trace& trace) const;
+
+ // Tells whether the two specified comparison rtx can be combined into a
+ // single comparison.
+ bool can_combine_comparisons (const_rtx x, const_rtx y) const;
+
+ // Tells whether the ccreg usage can be extended from the bb_entry on until
+ // the final cbranch of the trace.
+ bool can_extend_ccreg_usage (const bb_entry& e,
+ const cbranch_trace& trace) const;
+
+ // Create an insn rtx that is a negating reg move (not operation).
+ rtx make_not_reg_insn (rtx dst_reg, rtx src_reg) const;
+
+ // Create an insn rtx that inverts the ccreg.
+ rtx make_inv_ccreg_insn (void) const;
+
+ // Adds the specified insn to the set of modified or newly added insns that
+ // might need splitting at the end of the pass.
+ rtx touched_insn (rtx i);
+
+ // Try to invert the branch condition of the specified trace.
+ bool try_invert_branch_condition (cbranch_trace& trace);
+
+ // Try to optimize a cbranch trace by combining comparisons in BBs and
+ // eliminate the cstores.
+ bool try_combine_comparisons (cbranch_trace& trace,
+ int cstore_count, int inv_cstore_count,
+ cstore_type_t dominating_cstore);
+
+ // Try to optimize a cbranch trace by eliminating the cstores in BBs only.
+ bool try_eliminate_cstores (cbranch_trace& trace,
+ int cstore_count, int inv_cstore_count,
+ cstore_type_t dominating_cstore);
+
+ // Given a branch insn, try to optimize its branch condition.
+ // If any insns are modified or added they are added to 'touched_insns_'.
+ void try_optimize_cbranch (rtx i);
+};
+
+
+const pass_data ifcvt_sh::default_pass_data =
+{
+ RTL_PASS, // type
+ "", // name (overwritten by the constructor)
+ OPTGROUP_NONE, // optinfo_flags
+ true, // has_gate
+ true, // has_execute
+ TV_OPTIMIZE, // tv_id
+ 0, // properties_required
+ 0, // properties_provided
+ 0, // properties_destroyed
+ 0, // todo_flags_start
+ TODO_df_finish | TODO_df_verify // todo_flags_finish
+ | TODO_verify_rtl_sharing
+};
+
+ifcvt_sh::ifcvt_sh (gcc::context* ctx, bool split_insns, const char* name)
+: rtl_opt_pass (default_pass_data, ctx),
+ split_insns_ (split_insns),
+ en_logging_ (false),
+ ccreg_ (NULL_RTX)
+{
+ // Overwrite default name in pass_data base class.
+ this->name = name;
+}
+
+ifcvt_sh::~ifcvt_sh (void)
+{
+}
+
+void ifcvt_sh::update_ccreg_mode (const_rtx cond)
+{
+ if (REG_P (XEXP (cond, 0)) && REGNO (XEXP (cond, 0)) != REGNO (ccreg_))
+ return;
+
+ machine_mode m = GET_MODE (XEXP (cond, 0));
+ if (m == GET_MODE (ccreg_))
+ return;
+
+ PUT_MODE (ccreg_, m);
+ log_msg ("updated ccreg mode: ");
+ log_rtx (ccreg_);
+ log_msg ("\n");
+}
+
+bool
+ifcvt_sh::is_cmp_eq_zero (const_rtx i)
+{
+ return i != NULL_RTX && GET_CODE (i) == EQ
+ && REG_P (XEXP (i, 0)) && XEXP (i, 1) == const0_rtx;
+}
+
+ifcvt_sh::branch_condition_type_t
+ifcvt_sh::branch_condition_type (const_rtx cond) const
+{
+ if (cond == NULL_RTX)
+ return unknown_branch_condition;
+
+ if (GET_CODE (cond) == NE
+ && REG_P (XEXP (cond, 0)) && REGNO (XEXP (cond, 0)) == REGNO (ccreg_)
+ && XEXP (cond, 1) == const0_rtx)
+ return branch_if_true;
+
+ else if (GET_CODE (cond) == EQ
+ && REG_P (XEXP (cond, 0)) && REGNO (XEXP (cond, 0)) == REGNO (ccreg_)
+ && XEXP (cond, 1) == const0_rtx)
+ return branch_if_false;
+
+ else
+ return unknown_branch_condition;
+}
+
+bool
+ifcvt_sh::is_normal_ccreg (const_rtx x) const
+{
+ return t_reg_operand (const_cast<rtx> (x), VOIDmode);
+}
+
+bool
+ifcvt_sh::is_inverted_ccreg (const_rtx x) const
+{
+ return negt_reg_operand (const_cast<rtx> (x), VOIDmode);
+}
+
+ifcvt_sh::record_return_t
+ifcvt_sh::record_set_of_reg (rtx reg, rtx start_insn, bb_entry& new_entry)
+{
+ log_msg ("\n[bb %d]\n", new_entry.bb->index);
+
+ if (start_insn == NULL_RTX)
+ log_return (set_not_found, "set of reg not found. empty BB?\n");
+
+ new_entry.cstore_type = cstore_unknown;
+
+ for (rtx i = start_insn; i != NULL_RTX; )
+ {
+ new_entry.cstore = find_set_of_reg_bb (reg, i);
+
+ if (new_entry.cstore.set_src () == NULL_RTX)
+ log_return (set_not_found, "set of reg not found (cstore)\n");
+
+ log_insn (new_entry.cstore.insn);
+ log_msg ("\n");
+
+ if (is_normal_ccreg (new_entry.cstore.set_src ()))
+ {
+ log_msg ("normal condition store\n");
+ new_entry.cstore_type = cstore_normal;
+ }
+ else if (is_inverted_ccreg (new_entry.cstore.set_src ()))
+ {
+ log_msg ("inverted condition store\n");
+ new_entry.cstore_type = cstore_inverted;
+ }
+ else if (REG_P (new_entry.cstore.set_src ()))
+ {
+ // If it's a reg-reg copy follow the copied reg.
+ new_entry.cstore_reg_reg_copies.push_back (new_entry.cstore);
+ reg = new_entry.cstore.set_src ();
+ i = new_entry.cstore.insn;
+
+ log_msg ("reg-reg copy. tracing ");
+ log_rtx (reg);
+ log_msg ("\n");
+ continue;
+ }
+ else
+ log_return (other_set_found, "not a condition store\n");
+
+ gcc_assert (new_entry.cstore_type != cstore_unknown);
+
+ // Now see how the ccreg was set.
+ // For now it must be in the same BB.
+ log_msg ("tracing ccreg\n");
+ new_entry.setcc =
+ find_set_of_reg_bb (ccreg_,
+ prev_nonnote_insn_bb (new_entry.cstore.insn));
+
+ // If cstore was found but setcc was not found continue anyway, as
+ // for some of the optimization types the setcc is irrelevant.
+ if (new_entry.setcc.set_src () == NULL_RTX)
+ log_return (set_found, "set of ccreg not found\n");
+
+ else if (GET_CODE (new_entry.setcc.set_rtx) == SET)
+ {
+ // Also allow insns that set the ccreg, but are not true comparison
+ // insns, as long as they are sets and not e.g. clobbers.
+ log_insn (new_entry.setcc.insn);
+ log_msg ("\n");
+ return set_found;
+ }
+ else
+ // If cstore was found but setcc was not found continue anyway, as
+ // for some of the optimization types the setcc is irrelevant.
+ log_return (set_found, "unknown set of ccreg\n");
+ }
+
+ log_return (set_not_found, "set of reg not found\n");
+}
+
+bool
+ifcvt_sh::can_remove_cstore (const bb_entry& e,
+ const cbranch_trace& trace) const
+{
+ if (volatile_insn_p (PATTERN (e.cstore.insn)))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause it's volatile\n");
+ }
+
+ // On SH there are parallel patterns which store the ccreg multiple times.
+ // In this case it's not safe.
+ rtx cstore_pat = PATTERN (e.cstore.insn);
+ if (GET_CODE (cstore_pat) == PARALLEL)
+ for (int i = 0; i < XVECLEN (cstore_pat, 0); ++i)
+ {
+ rtx x = XVECEXP (cstore_pat, 0, i);
+
+ // It's the cstore set that we're referring to, ignore that one.
+ if (x != e.cstore.set_rtx
+ && GET_CODE (x) == SET && reg_referenced_p (ccreg_, x))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause it's a multiple ccreg store\n");
+ }
+ }
+
+ // If the cstore sets the ccreg (e.g. negc) and the ccreg is used afterwards
+ // it's not safe.
+ if (modified_in_p (ccreg_, e.cstore.insn)
+ && !(reg_dead_after_insn (ccreg_, e.cstore.insn)
+ || reg_unused_after_insn (ccreg_, e.cstore.insn)))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause it sets the ccreg\n");
+ }
+
+ // If the cstore destination reg is copied around check the reg-reg
+ // copies. At every reg-reg copy the copied reg must be dead.
+ // Otherwise we assume that the result of the cstore is used in some
+ // other way.
+ for (std::vector<set_of_reg>::const_reverse_iterator i =
+ e.cstore_reg_reg_copies.rbegin ();
+ i != e.cstore_reg_reg_copies.rend (); ++i)
+ {
+ if (!reg_dead_after_insn (i->set_src (), i->insn))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (i->insn);
+ log_return (false, "\nbecause source of reg-reg copy doesn't die\n");
+ }
+ }
+
+ // Check that the destination reg of the cstore is not used otherwise.
+
+ // If the cstore destination reg is copied around check the effective
+ // destination reg of the cstore. The reg-reg copies are recorded in
+ // reverse order, i.e. the most recent reg-reg copy in the insn list
+ // comes first.
+ rtx cstore_dst = e.cstore_reg_reg_copies.empty ()
+ ? e.cstore.set_dst ()
+ : e.cstore_reg_reg_copies.front ().set_dst ();
+
+ // The cstore_dst reg must die after the test before the cbranch.
+ if (!reg_dead_after_insn (cstore_dst, trace.setcc.insn))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause its effective target reg %d doesn't die "
+ "after trace.setcc.insn\n", REGNO (cstore_dst));
+ }
+
+ // Even if the cstore_dst reg dies after the test before the cbranch we
+ // have to check whether it is used in other BBs if the cstore is not
+ // in the same BB where the cstore_dst dies.
+ if (e.bb == trace.bb ())
+ {
+ if (reg_used_between_p (cstore_dst, e.cstore.insn, trace.setcc.insn))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause its effective target reg %d is used "
+ "otherwise\n", REGNO (cstore_dst));
+ }
+ }
+ else
+ {
+ // Count the uses of cstore_dst reg in all BBs that can be reached from
+ // bb_entry's BB. If we get more than '1' we assume that it's used
+ // somewhere else and is not safe to be removed.
+ int cstore_dst_use_count = trace_reg_uses (cstore_dst, e.cstore.insn,
+ trace.setcc.insn);
+ if (cstore_dst_use_count > 1)
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause its effective target reg %d is used "
+ "in %d other places\n", REGNO (cstore_dst),
+ cstore_dst_use_count - 1);
+ }
+ }
+
+ return true;
+}
+
+bool
+ifcvt_sh::can_remove_comparison (const bb_entry& e,
+ const cbranch_trace&/* trace*/) const
+{
+ // If the ccreg is used otherwise between the comparison and the cstore,
+ // it's not safe.
+ if (reg_used_between_p (ccreg_, e.setcc.insn, e.cstore.insn))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.setcc.insn);
+ log_return (false, "\nbecause the ccreg is used otherwise\n");
+ }
+
+ if (!reg_dead_after_insn (ccreg_, e.cstore.insn)
+ && !reg_unused_after_insn (ccreg_, e.cstore.insn))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause ccreg is not dead or unused afterwards\n");
+ }
+
+ // On SH there are also multiple set patterns that can be used for
+ // comparisons, such as "shll". It's not safe to remove those.
+ if (multiple_sets (e.setcc.insn))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (e.cstore.insn);
+ log_return (false, "\nbecause it's a multiple set\n");
+ }
+
+ return true;
+}
+
+rtx
+ifcvt_sh::make_not_reg_insn (rtx dst_reg, rtx src_reg) const
+{
+ // This will to go through expanders and may output multiple insns
+ // for multi-word regs.
+ start_sequence ();
+ expand_simple_unop (GET_MODE (dst_reg), NOT, src_reg, dst_reg, 0);
+ rtx i = get_insns ();
+ end_sequence ();
+ return i;
+}
+
+rtx
+ifcvt_sh::make_inv_ccreg_insn (void) const
+{
+ start_sequence ();
+ rtx i = emit_insn (gen_rtx_SET (VOIDmode, ccreg_,
+ gen_rtx_fmt_ee (XOR, GET_MODE (ccreg_),
+ ccreg_, const1_rtx)));
+ end_sequence ();
+ return i;
+}
+
+rtx
+ifcvt_sh::touched_insn (rtx i)
+{
+ touched_insns_.push_back (i);
+ return i;
+}
+
+bool
+ifcvt_sh::can_combine_comparisons (const_rtx x, const_rtx y) const
+{
+ if (GET_CODE (x) != GET_CODE (y))
+ return false;
+
+ rtx x_op0 = XEXP (x, 0);
+ rtx x_op1 = XEXP (x, 1);
+
+ rtx y_op0 = XEXP (y, 0);
+ rtx y_op1 = XEXP (y, 1);
+
+ if (!REG_P (x_op0) || !REG_P (y_op0))
+ return false;
+
+ if (GET_MODE (x_op0) != GET_MODE (y_op0))
+ return false;
+
+ // rtx_equal_p also compares the reg numbers which we do not care about
+ // here, as long as both are regs and the modes are the same.
+ if (REG_P (x_op1))
+ return REG_P (y_op1) && GET_MODE (x_op1) == GET_MODE (y_op1);
+
+ return rtx_equal_p (x_op1, y_op1);
+}
+
+bool
+ifcvt_sh::can_extend_ccreg_usage (const bb_entry& e,
+ const cbranch_trace& trace) const
+{
+ // Check if the ccreg is not modified by other insins in the BB path until
+ // the final cbranch of the trace.
+ // Start checking after the cstore that follows the setcc, assuming that
+ // the cstore will be removed.
+
+ // The assumption here is that the specified bb_entry's BB is a direct
+ // predecessor of the trace.cbranch_insn's BB.
+ if (e.bb != trace.bb () && !is_adjacent_bb (e.bb, trace.bb ()))
+ log_return (false,
+ "can't extend ccreg usage -- [bb %d] and [bb %d] are not adjacent\n",
+ e.bb->index, trace.bb ()->index);
+
+ if (e.cstore.empty ())
+ log_return (false, "can't extend ccreg usage -- no cstore\n");
+
+ // The entry's cstore is in the same BB as the final cbranch.
+ if (e.bb == trace.bb ())
+ {
+ if (reg_set_between_p (ccreg_, e.cstore.insn, trace.setcc.insn))
+ log_return (false,
+ "can't extend ccreg usage -- it's modified between e.cstore.insn "
+ "and trace.setcc.insn");
+ else
+ return true;
+ }
+
+ // The entry's cstore and the final cbranch are in different BBs.
+ if (reg_set_between_p (ccreg_, e.cstore.insn, NEXT_INSN (BB_END (e.bb))))
+ log_return (false,
+ "can't extend ccreg usage -- it's modified in [bb %d]", e.bb->index);
+
+ if (reg_set_between_p (ccreg_, PREV_INSN (BB_HEAD (trace.bb ())),
+ trace.setcc.insn))
+ log_return (false,
+ "can't extend ccreg usage -- it's modified in [bb %d]",
+ trace.bb ()->index);
+
+ return true;
+}
+
+bool
+ifcvt_sh::try_invert_branch_condition (cbranch_trace& trace)
+{
+ log_msg ("inverting branch condition\n");
+
+ if (!invert_jump_1 (trace.cbranch_insn, JUMP_LABEL (trace.cbranch_insn)))
+ log_return (false, "invert_jump_1 failed\n");
+
+ if (verify_changes (num_validated_changes ()))
+ confirm_change_group ();
+ else
+ log_return (false, "verify_changed failed\n");
+
+ touched_insn (trace.cbranch_insn);
+ return true;
+}
+
+bool
+ifcvt_sh::try_combine_comparisons (cbranch_trace& trace,
+ int cstore_count, int inv_cstore_count,
+ cstore_type_t dominating_cstore)
+{
+ log_msg ("\ntry_combine_comparisons\n");
+
+ // This function will always try to create new pseudos.
+ if (!can_create_pseudo_p ())
+ log_return (false, "can't create pseudos\n");
+
+ // Check that all ccset insns are comparisons and all comparison types in
+ // all BBs are the same and could be combined into one single comparison.
+ rtx comp = NULL_RTX;
+ rtx comp_insn = NULL_RTX;
+
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ int i_empty_count = i->setcc.empty () + i->cstore.empty ();
+
+ // A completly empty entry is OK (could be the BB of the cbranch).
+ if (i_empty_count == 2)
+ continue;
+
+ // Otherwise we need both, the setcc and the cstore.
+ if (i_empty_count != 0)
+ log_return (false, "bb entry is not a setcc cstore pair\n");
+
+ rtx other_comp = i->comparison_rtx ();
+
+ if (!COMPARISON_P (other_comp))
+ {
+ log_msg ("setcc is not a comparison:\n");
+ log_rtx (other_comp);
+ log_return (false, "\n");
+ }
+
+ if (comp_insn == NULL_RTX)
+ {
+ comp = other_comp;
+ comp_insn = i->setcc.insn;
+ }
+ else if (!can_combine_comparisons (comp, other_comp))
+ return false;
+
+ // The goal here is to eliminate all cstores and comparisons in the BBs.
+ // Thus check if every cstore can actually be removed safely.
+ if (!can_remove_cstore (*i, trace) || !can_remove_comparison (*i, trace))
+ return false;
+ }
+
+ // FIXME: The first operand of the comparison must be a simple reg.
+ // This effectively prohibits combining div0s comparisons such as
+ // (lt:SI (xor:SI (reg:SI) (reg:SI)))
+ if (!REG_P (XEXP (comp, 0)))
+ {
+ log_msg ("comparison operand 0\n");
+ log_rtx (XEXP (comp, 0));
+ log_return (false, "\nis not a reg\n");
+ }
+
+ rtx comp_op0 = gen_reg_rtx (GET_MODE (XEXP (comp, 0)));
+ rtx comp_op1 = REG_P (XEXP (comp, 1))
+ ? gen_reg_rtx (GET_MODE (XEXP (comp, 1)))
+ : XEXP (comp, 1);
+
+ // If there are both, inverting and non-inverting cstores, they can only
+ // be eliminated if the comparison can be inverted. We assume that the
+ // comparison insns that we find are already minimal and canonicalized.
+ // There is one special case though, where an integer comparison
+ // (eq (reg) (const_int 0))
+ // can be inverted with a sequence
+ // (eq (not (reg)) (const_int 0))
+ if (inv_cstore_count != 0 && cstore_count != 0)
+ {
+ if (make_not_reg_insn (comp_op0, comp_op0) == NULL_RTX)
+ log_return (false, "make_not_reg_insn failed.\n");
+
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ if (i->setcc.empty () || i->cstore.empty ())
+ continue;
+
+ if (i->cstore_type != dominating_cstore
+ && !is_cmp_eq_zero (i->comparison_rtx ()))
+ {
+ log_msg ("can't invert comparison in insn\n");
+ log_insn (i->setcc.insn);
+ log_return (false,
+ "\nbecause it's not a (eq (reg) (const_int 0))\n");
+ }
+ }
+ }
+
+ if (dominating_cstore == cstore_normal
+ && !try_invert_branch_condition (trace))
+ return false;
+
+ // Replace the test insn before the cbranch with the common comparison.
+ // Instead of creating a new insn from scratch we copy the common comparison
+ // pattern. This simplifies handling parallel comparison patterns, such as
+ // FP comparisons on SH, which have an extra use on FPSCR.
+ log_msg ("installing common comparison in [bb %d]\n", trace.bb ()->index);
+
+ rtx common_comp_pat = copy_rtx (PATTERN (comp_insn));
+ rtx common_comp = const_cast<rtx> (set_of (ccreg_, common_comp_pat));
+
+ gcc_assert (common_comp != NULL_RTX);
+
+ XEXP (XEXP (common_comp, 1), 0) = comp_op0;
+ XEXP (XEXP (common_comp, 1), 1) = comp_op1;
+
+ log_rtx (common_comp_pat);
+ log_msg ("\n");
+
+ touched_insn (emit_insn_after (common_comp_pat, trace.setcc.insn));
+ delete_insn (trace.setcc.insn);
+
+ // Replace comparison and cstore insns with reg-reg moves in all BBs.
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ if (i->setcc.empty () || i->cstore.empty ())
+ continue;
+
+ if (i->cstore_type == dominating_cstore)
+ {
+ log_msg ("replacing comparison and cstore with reg move "
+ "in [bb %d]\n", i->bb->index);
+
+ touched_insn (emit_insn_after (
+ gen_move_insn (comp_op0, XEXP (i->comparison_rtx (), 0)),
+ i->setcc.insn));
+
+ // If the second operand is a reg, have to emit a move insn.
+ // Otherwise assume it's a const_int and just reference it.
+ if (REG_P (comp_op1))
+ touched_insn (emit_insn_after (
+ gen_move_insn (comp_op1, XEXP (i->comparison_rtx (), 1)),
+ i->setcc.insn));
+ }
+ else
+ {
+ log_msg ("replacing comparison and cstore with inverting reg move "
+ "in [bb %d]\n", i->bb->index);
+
+ rtx new_i = make_not_reg_insn (comp_op0,
+ XEXP (i->comparison_rtx (), 0));
+ touched_insn (emit_insn_after (new_i, i->setcc.insn));
+ }
+
+ delete_insn (i->cstore.insn);
+ delete_insn (i->setcc.insn);
+ }
+
+ return true;
+}
+
+bool
+ifcvt_sh::try_eliminate_cstores (cbranch_trace& trace,
+ int cstore_count, int inv_cstore_count,
+ cstore_type_t dominating_cstore)
+{
+ log_msg ("\ntry_eliminate_cstores\n");
+
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ // A completly empty entry is OK (could be the BB of the cbranch).
+ if (i->setcc.empty () && i->cstore.empty ())
+ continue;
+
+ // We're going to eliminate cstores, but for that they have to be
+ // there. We don't care about the setcc in this case.
+ if (i->cstore.empty ())
+ log_return (false, "bb entry cstore empty -- aborting\n");
+
+ // The goal here is to eliminate all cstores in the BBs and extend the
+ // ccreg usage.
+ if (!can_extend_ccreg_usage (*i, trace))
+ return false;
+
+ // If the cstore can't be removed we can keep it around as long as
+ // it doesn't modify the ccreg.
+ if (!can_remove_cstore (*i, trace)
+ && modified_in_p (ccreg_, i->cstore.insn))
+ log_return (false, "cstore sets ccreg -- aborting\n");
+ }
+
+ // If there are both, inverting and non-inverting cstores, we'll have to
+ // invert the ccreg as a replacement for one of them.
+ if (cstore_count != 0 && inv_cstore_count != 0)
+ {
+ rtx i = make_inv_ccreg_insn ();
+ if (recog_memoized (i) < 0)
+ {
+ log_msg ("failed to match ccreg inversion insn:\n");
+ log_rtx (PATTERN (i));
+ log_return (false, "\naborting\n");
+ }
+ }
+
+ if (dominating_cstore == cstore_normal
+ && !try_invert_branch_condition (trace))
+ return false;
+
+ // Eliminate cstores in all BBs.
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ if (i->cstore.empty ())
+ continue;
+
+ if (i->cstore_type == dominating_cstore)
+ log_msg ("removing cstore in [bb %d]\n", i->bb->index);
+ else
+ {
+ log_msg ("replacing cstore with ccreg inversion in [bb %d]\n",
+ i->bb->index);
+
+ touched_insn (
+ emit_insn_after (make_inv_ccreg_insn (), i->cstore.insn));
+ }
+
+ if (can_remove_cstore (*i, trace))
+ delete_insn (i->cstore.insn);
+ }
+
+ log_msg ("removing test insn before cbranch\n");
+ delete_insn (trace.setcc.insn);
+ return true;
+}
+
+void
+ifcvt_sh::try_optimize_cbranch (rtx insn)
+{
+ cbranch_trace trace (insn);
+
+ log_msg ("\n\n--------------------------------------\n");
+ log_msg ("found cbranch insn in [bb %d]:\n", trace.bb ()->index);
+ log_insn (insn);
+
+ trace.cbranch_type = branch_condition_type (trace.branch_condition_rtx ());
+
+ if (trace.cbranch_type == branch_if_true)
+ log_msg ("condition: branch if true\n");
+ else if (trace.cbranch_type == branch_if_false)
+ log_msg ("condition: branch if false\n");
+ else
+ {
+ log_msg ("unknown branch condition\n");
+ log_rtx (trace.branch_condition_rtx ());
+ log_return_void ("\n");
+ }
+
+ update_ccreg_mode (trace.branch_condition_rtx ());
+
+ // Scan the insns backwards for an insn that sets the ccreg by testing a
+ // reg against zero like
+ // (set (reg ccreg) (eq (reg) (const_int 0)))
+ // The testing insn could also be outside of the current basic block, but
+ // for now we limit the search to the current basic block.
+ trace.setcc = find_set_of_reg_bb (ccreg_, prev_nonnote_insn_bb (insn));
+
+ if (!is_cmp_eq_zero (trace.setcc.set_src ()))
+ log_return_void ("could not find set of ccreg in current BB\n");
+
+ rtx trace_reg = XEXP (trace.setcc.set_src (), 0);
+
+ log_msg ("set of ccreg:\n");
+ log_insn (trace.setcc.insn);
+
+ // See if we can remove the trace.setcc insn safely.
+ if (reg_used_between_p (ccreg_, trace.setcc.insn, trace.cbranch_insn))
+ log_return_void ("ccreg used between testing insn and branch insn\n");
+
+ if (volatile_insn_p (PATTERN (trace.setcc.insn)))
+ {
+ log_msg ("can't remove insn\n");
+ log_insn (trace.setcc.insn);
+ log_return_void ("\nbecause it's volatile\n");
+ }
+
+ // Now that we have an insn which tests some reg and sets the condition
+ // reg before the conditional branch, try to figure out how that tested
+ // reg was formed, i.e. find all the insns that set the tested reg in
+ // some way.
+ // The tested reg might be set in multiple basic blocks so we need to
+ // check all basic blocks which can reach this current basic block.
+ // If the set of reg is an inverting or non-inverting store of the condition
+ // register, check how the ccreg value was obtained.
+ log_msg ("\ntracing ");
+ log_rtx (trace_reg);
+ log_msg ("\n");
+
+
+ // First check the basic block where the conditional branch is in.
+ // If we find it here there's no point in checking other BBs.
+ trace.bb_entries.push_front (bb_entry (trace.bb ()));
+
+ record_return_t res =
+ record_set_of_reg (trace_reg, prev_nonnote_insn_bb (trace.setcc.insn),
+ trace.bb_entries.front ());
+
+ if (res == other_set_found)
+ log_return_void ("other set found - aborting trace\n");
+ else if (res == set_not_found)
+ {
+ // It seems the initial search in the BB of the conditional branch
+ // didn't find anything. Now look in all predecessor BBs.
+ for (edge_iterator ei = ei_start (trace.bb ()->preds);
+ !ei_end_p (ei); ei_next (&ei))
+ {
+ edge e = ei_edge (ei);
+ trace.bb_entries.push_front (bb_entry (e->src));
+
+ res = record_set_of_reg (trace_reg, BB_END (e->src),
+ trace.bb_entries.front ());
+ if (res != set_found)
+ log_return_void ("set not found - aborting trace\n");
+ }
+ }
+
+ if (en_logging_)
+ {
+ log_msg ("\ncbranch trace summary:\n");
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ log_msg ("\n[bb %d]\n", i->bb->index);
+ if (!i->setcc.empty ())
+ {
+ log_rtx (i->setcc.set_rtx);
+ log_msg ("\n");
+ }
+ if (!i->cstore.empty ())
+ {
+ log_rtx (i->cstore.set_rtx);
+ log_msg ("\n");
+ }
+
+ for (std::vector<set_of_reg>::const_reverse_iterator j =
+ i->cstore_reg_reg_copies.rbegin ();
+ j != i->cstore_reg_reg_copies.rend (); ++j)
+ {
+ log_rtx (j->set_rtx);
+ log_msg ("\n");
+ }
+ }
+
+ log_rtx (trace.setcc.set_rtx);
+ log_msg ("\n");
+ log_rtx (PATTERN (trace.cbranch_insn));
+ log_msg ("\n");
+ }
+
+ // Check that we don't have any empty BBs.
+ // Only the BB with the cbranch may be empty.
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ if (i->setcc.empty () && i->cstore.empty () && i->bb != trace.bb ())
+ log_return_void ("\n[bb %d] is empty - aborting.\n", i->bb->index);
+
+ // Determine the dominating cstore type
+ // FIXME: Try to take the probabilities of the BBs into account somehow.
+ int cstore_count = 0;
+ int inv_cstore_count = 0;
+
+ for (std::list<bb_entry>::const_iterator i = trace.bb_entries.begin ();
+ i != trace.bb_entries.end (); ++i)
+ {
+ if (i->cstore_type == cstore_normal)
+ cstore_count += 1;
+ else if (i->cstore_type == cstore_inverted)
+ inv_cstore_count += 1;
+ }
+
+ log_msg ("cstore count = %d inverted cstore count = %d\n",
+ cstore_count, inv_cstore_count);
+
+ // This puts a priority on inverting cstores.
+ cstore_type_t dominating_cstore = inv_cstore_count >= cstore_count
+ ? cstore_inverted
+ : cstore_normal;
+
+ if (dominating_cstore == cstore_inverted)
+ log_msg ("will try to eliminate inverted cstore\n");
+ else if (dominating_cstore == cstore_normal)
+ {
+ log_msg ("will try to eliminate normal cstore\n");
+ if (!trace.can_invert_condition ())
+ log_return_void ("branch condition can't be inverted - aborting\n");
+ }
+ else
+ gcc_unreachable ();
+
+ if (try_combine_comparisons (trace, cstore_count, inv_cstore_count,
+ dominating_cstore))
+ return;
+
+ try_eliminate_cstores (trace, cstore_count, inv_cstore_count,
+ dominating_cstore);
+}
+
+bool
+ifcvt_sh::gate (void)
+{
+ return optimize > 0;
+}
+
+unsigned int
+ifcvt_sh::execute (void)
+{
+ en_logging_ = dump_file != NULL;
+
+ unsigned int ccr0 = INVALID_REGNUM;
+ unsigned int ccr1 = INVALID_REGNUM;
+
+ if (targetm.fixed_condition_code_regs (&ccr0, &ccr1)
+ && ccr0 != INVALID_REGNUM)
+ {
+ // Initially create a reg rtx with VOIDmode.
+ // When the first conditional branch is discovered, the mode is changed
+ // to the mode that is actually used by the target.
+ ccreg_ = gen_rtx_REG (VOIDmode, ccr0);
+ }
+
+ if (ccreg_ == NULL_RTX)
+ log_return (0, "no ccreg.\n\n");
+
+ if (STORE_FLAG_VALUE != 1)
+ log_return (0, "unsupported STORE_FLAG_VALUE %d", STORE_FLAG_VALUE);
+
+ log_msg ("ccreg: ");
+ log_rtx (ccreg_);
+ log_msg (" STORE_FLAG_VALUE = %d\n", STORE_FLAG_VALUE);
+
+ // Look for basic blocks that end with a conditional branch and try to
+ // optimize them.
+ basic_block bb;
+ FOR_EACH_BB (bb)
+ {
+ rtx i = BB_END (bb);
+ if (any_condjump_p (i) && onlyjump_p (i))
+ try_optimize_cbranch (i);
+ }
+
+ log_msg ("\n\n");
+
+ // If new insns are created and this pass is executed after all insns
+ // have been split already, we must split the insns we've changed or added
+ // ourselves here.
+ // FIXME: Multi-word operations (which emit multiple insns) are not handled
+ // properly here, since only one insn will end up in 'touched_insns_'.
+ // On SH this is not a problem though.
+ if (split_insns_)
+ for (std::vector<rtx>::const_iterator i = touched_insns_.begin ();
+ i != touched_insns_.end (); ++i)
+ {
+ log_msg ("trying to split insn:\n");
+ log_insn (*i);
+ log_msg ("\n");
+ try_split (PATTERN (*i), *i, 0);
+ }
+
+ touched_insns_.clear ();
+ log_return (0, "\n\n");
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+// This allows instantiating the pass somewhere else without having to pull
+// in a header file.
+opt_pass*
+make_pass_ifcvt_sh (gcc::context* ctx, bool split_insns, const char* name)
+{
+ return new ifcvt_sh (ctx, split_insns, name);
+}
Hello, Some of the things I've done in 4.8 to improve SH T bit handling turned out to produce wrong code. The attached patch fixes that by introducing an SH specific RTL pass. Tested on rev 202876 with make -k check RUNTESTFLAGS="--target_board=sh-sim \{-m2/-ml,-m2/-mb,-m2a/-mb,-m4/-ml,-m4/-mb,-m4a/-ml,-m4a/-mb}" and no new failures. Additional test cases will follow. OK for trunk? Cheers, Oleg gcc/ChangeLog: PR target/51244 * config/sh/ifcvt_sh.cc: New SH specific RTL pass. * config.gcc (SH extra_objs): Add ifcvt_sh.o. * config/sh/t-sh (ifcvt_sh.o): New entry. * config/sh/sh.c (sh_fixed_condition_code_regs): New function that implements the target hook TARGET_FIXED_CONDITION_CODE_REGS. (register_sh_passes): New function. Register ifcvt_sh pass. (sh_option_override): Invoke it. (sh_canonicalize_comparison): Handle op0_preserve_value. * sh.md (*cbranch_t"): Do not try to optimize missed test and branch opportunities. Canonicalize branch condition. (nott): Allow only if pseudos can be created for non-SH2A.