diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a27835d9ff6acbff4916f436eeffd5974b312afa..07d016c072603ae9b8d963a233ef15496318e746 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2003-06-24 Zdenek Dvorak <rakdver@atrey.karlin.mff.cuni.cz>
+
+ * Makefile.in (cfgrtl.o): Add expr.h dependency.
+ * cfgrtl.c: Include expr.h.
+ (mark_killed_regs, safe_insert_insn_on_edge): New
+ functions.
+ * config/i386/i386.h (AVOID_CCMODE_COPIES): Define.
+ * basic-block.h (safe_insert_insn_on_edge): Declare.
+
2003-06-26 Neil Booth <neil@daikokuya.co.uk>
* c-opts.c (missing_arg): Make non-static.
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index a3cc5df30ecc9d0325a480eb4caafe16bc768f44..5029c52db229660339297e8649b02a3d9854b2c6 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -1659,7 +1659,7 @@ cfghooks.o: cfghooks.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) $(TR
$(BASIC_BLOCK_H) cfglayout.h
cfgrtl.o : cfgrtl.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) flags.h \
insn-config.h $(BASIC_BLOCK_H) $(REGS_H) hard-reg-set.h output.h toplev.h $(RECOG_H) \
- function.h except.h $(GGC_H) $(TM_P_H) insn-config.h
+ function.h except.h $(GGC_H) $(TM_P_H) insn-config.h $(EXPR_H)
cfganal.o : cfganal.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) \
$(BASIC_BLOCK_H) hard-reg-set.h insn-config.h $(RECOG_H) $(GGC_H) $(TM_P_H)
cfgbuild.o : cfgbuild.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) flags.h \
diff --git a/gcc/basic-block.h b/gcc/basic-block.h
index 40775b9ad9a0b5e6e2b89a6d55de03fdc485a7da..b26b14399d11122158b1ce4f8c370dbb8efd63a6 100644
--- a/gcc/basic-block.h
+++ b/gcc/basic-block.h
@@ -340,6 +340,7 @@ extern void update_bb_for_insn PARAMS ((basic_block));
extern void free_basic_block_vars PARAMS ((int));
extern void insert_insn_on_edge PARAMS ((rtx, edge));
+bool safe_insert_insn_on_edge (rtx, edge);
extern void commit_edge_insertions PARAMS ((void));
extern void commit_edge_insertions_watch_calls PARAMS ((void));
diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c
index 569a6049882c93c28a244fdff0fcefe05eb5147a..a08d29f3da94da025d181a60f039e04c8c9dfa63 100644
--- a/gcc/cfgrtl.c
+++ b/gcc/cfgrtl.c
@@ -56,6 +56,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
#include "obstack.h"
#include "insn-config.h"
#include "cfglayout.h"
+#include "expr.h"
/* Stubs in case we don't have a return insn. */
#ifndef HAVE_return
@@ -88,6 +89,7 @@ static bool rtl_redirect_edge_and_branch (edge, basic_block);
static edge rtl_split_block (basic_block, void *);
static void rtl_dump_bb (basic_block, FILE *);
static int rtl_verify_flow_info_1 (void);
+static void mark_killed_regs (rtx, rtx, void *);
/* Return true if NOTE is not one of the ones that must be kept paired,
so that we may simply delete it. */
@@ -1305,6 +1307,101 @@ insert_insn_on_edge (rtx pattern, edge e)
end_sequence ();
}
+/* Called from safe_insert_insn_on_edge through note_stores, marks live
+ registers that are killed by the store. */
+static void
+mark_killed_regs (rtx reg, rtx set ATTRIBUTE_UNUSED, void *data)
+{
+ regset killed = data;
+ int regno, i;
+
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+ if (!REG_P (reg))
+ return;
+ regno = REGNO (reg);
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ SET_REGNO_REG_SET (killed, regno);
+ else
+ {
+ for (i = 0; i < HARD_REGNO_NREGS (regno, GET_MODE (reg)); i++)
+ SET_REGNO_REG_SET (killed, regno + i);
+ }
+}
+
+/* Similar to insert_insn_on_edge, tries to put INSN to edge E. Additionally
+ it checks whether this will not clobber the registers that are live on the
+ edge (i.e. it requieres liveness information to be up-to-date) and if there
+ are some, then it tries to save and restore them. Returns true if
+ succesful. */
+bool
+safe_insert_insn_on_edge (rtx insn, edge e)
+{
+ rtx x;
+ regset_head killed_head;
+ regset killed = INITIALIZE_REG_SET (killed_head);
+ rtx save_regs = NULL_RTX;
+ int regno, noccmode;
+ enum machine_mode mode;
+
+#ifdef AVOID_CCMODE_COPIES
+ noccmode = true;
+#else
+ noccmode = false;
+#endif
+
+ for (x = insn; x; x = NEXT_INSN (x))
+ if (INSN_P (x))
+ note_stores (PATTERN (x), mark_killed_regs, killed);
+ bitmap_operation (killed, killed, e->dest->global_live_at_start,
+ BITMAP_AND);
+
+ EXECUTE_IF_SET_IN_REG_SET (killed, 0, regno,
+ {
+ mode = regno < FIRST_PSEUDO_REGISTER
+ ? reg_raw_mode[regno]
+ : GET_MODE (regno_reg_rtx[regno]);
+ if (mode == VOIDmode)
+ return false;
+
+ if (noccmode && mode == CCmode)
+ return false;
+
+ save_regs = alloc_EXPR_LIST (0,
+ alloc_EXPR_LIST (0,
+ gen_reg_rtx (mode),
+ gen_raw_REG (mode, regno)),
+ save_regs);
+ });
+
+ if (save_regs)
+ {
+ rtx from, to;
+
+ start_sequence ();
+ for (x = save_regs; x; x = XEXP (x, 1))
+ {
+ from = XEXP (XEXP (x, 0), 1);
+ to = XEXP (XEXP (x, 0), 0);
+ emit_move_insn (to, from);
+ }
+ emit_insn (insn);
+ for (x = save_regs; x; x = XEXP (x, 1))
+ {
+ from = XEXP (XEXP (x, 0), 0);
+ to = XEXP (XEXP (x, 0), 1);
+ emit_move_insn (to, from);
+ }
+ insn = get_insns ();
+ end_sequence ();
+ free_EXPR_LIST_list (&save_regs);
+ }
+ insert_insn_on_edge (insn, e);
+
+ FREE_REG_SET (killed);
+ return true;
+}
+
/* Update the CFG for the instructions queued on edge E. */
static void
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 5f390f0e1552676cf1ec3319d154aa11ed0f8c63..c115f6a21997a959e95b05974fa962a2c4d293df 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -1123,6 +1123,9 @@ do { \
&& (TARGET_64BIT || !TARGET_PARTIAL_REG_STALL)) \
|| ((MODE2) == DImode && TARGET_64BIT))))
+/* It is possible to write patterns to move flags; but until someone
+ does it, */
+#define AVOID_CCMODE_COPIES
/* Specify the modes required to caller save a given hard regno.
We do this on i386 to prevent flags from being saved at all.