i386.c (ix86_fp_comparison_arithmetics_cost, [...]): New functions.

	* i386.c (ix86_fp_comparison_arithmetics_cost,
	ix86_fp_comparison_fcomi_cost, ix86_fp_comparison_sahf_cost,
	ix86_fp_comparison_cost): New functions.
	(ix86_expand_fp_compare): Use the costs to choose best bethod; add
	two new parameters SECOND_TEST and BYPASS_TEST; allow generating
	two-branch sequences; make static.
	(ix86_use_fcomi_compare): Do decision according to the costs.
	(split_fp_branch): New.
	* i386.md (compare-and-branch patterns): Use split_fp_branch.
	* i386-protos.h (ix86_expand_fp_compare): Remove
	(ix86_split_fp_branch): Declare.

	* i386.h (PREDICATE_CODES): Update codes from fcmov_comparison_operand
	and ix86_comparison_operator.

	* i386.c (ix86_prepare_fp_compare_args): Try to rearange the comparison
	to make it cheaper.

	* i386.c (put_condition_code): Output properly the unordered/ordered
	compares in fp case.
	(ix86_expand_fp_movcc): Use ix86_expand_compare infrastructure.

	* tm.texi (REVERSE_CONDITION): Document.
	* i386.c (ix86_fp_compare_mode): Simplify; return always CCFPmode
	in -ffast-math mode.
	* i386.h (REVERSE_CONDITION, REVERSIBLE_CC_MODE): New macro.

From-SVN: r38979

gcc/ChangeLog

+Sat Jan 13 09:53:32 MET 2001  Jan Hubicka  <jh@suse.cz>
+
+	* i386.c (ix86_fp_comparison_arithmetics_cost,
+	ix86_fp_comparison_fcomi_cost, ix86_fp_comparison_sahf_cost,
+	ix86_fp_comparison_cost): New functions.
+	(ix86_expand_fp_compare): Use the costs to choose best bethod; add
+	two new parameters SECOND_TEST and BYPASS_TEST; allow generating
+	two-branch sequences; make static.
+	(ix86_use_fcomi_compare): Do decision according to the costs.
+	(split_fp_branch): New.
+	* i386.md (compare-and-branch patterns): Use split_fp_branch.
+	* i386-protos.h (ix86_expand_fp_compare): Remove
+	(ix86_split_fp_branch): Declare.
+
+	* i386.h (PREDICATE_CODES): Update codes from fcmov_comparison_operand
+	and ix86_comparison_operator.
+
+	* i386.c (ix86_prepare_fp_compare_args): Try to rearange the comparison
+	to make it cheaper.
+
+	* i386.c (put_condition_code): Output properly the unordered/ordered
+	compares in fp case.
+	(ix86_expand_fp_movcc): Use ix86_expand_compare infrastructure.
+
+	* tm.texi (REVERSE_CONDITION): Document.
+	* i386.c (ix86_fp_compare_mode): Simplify; return always CCFPmode
+	in -ffast-math mode.
+	* i386.h (REVERSE_CONDITION, REVERSIBLE_CC_MODE): New macro.
+
 2001-01-13  Alexandre Oliva  <aoliva@redhat.com>
 
 	* config/sh/sh.c (sh_expand_epilogue): Use PR explicitly.

gcc/config/i386/i386-protos.h

@@ -101,7 +101,6 @@ extern void ix86_expand_unary_operator PARAMS ((enum rtx_code, enum machine_mode
 extern int ix86_unary_operator_ok PARAMS ((enum rtx_code, enum machine_mode,
 					 rtx[]));
 extern int ix86_match_ccmode PARAMS ((rtx, enum machine_mode));
-extern rtx ix86_expand_fp_compare PARAMS ((enum rtx_code, rtx, rtx, rtx));
 extern rtx ix86_expand_compare PARAMS ((enum rtx_code));
 extern int ix86_use_fcomi_compare PARAMS ((enum rtx_code));
 extern void ix86_expand_branch PARAMS ((enum rtx_code, rtx));
@@ -129,6 +128,7 @@ extern enum machine_mode ix86_fp_compare_mode PARAMS ((enum rtx_code));
 
 extern rtx ix86_force_to_memory PARAMS ((enum machine_mode, rtx));
 extern void ix86_free_from_memory PARAMS ((enum machine_mode));
+extern void ix86_split_fp_branch PARAMS ((rtx, rtx, rtx, rtx, rtx, rtx));
 
 #ifdef TREE_CODE
 extern void init_cumulative_args PARAMS ((CUMULATIVE_ARGS *, tree, rtx));

gcc/config/i386/i386.h

@@ -2532,6 +2532,18 @@ while (0)
    possible, to allow for more combinations.  */
 
 #define SELECT_CC_MODE(OP,X,Y) ix86_cc_mode (OP, X, Y)
+
+/* Return non-zero if MODE implies a floating point inequality can be
+   reversed.  */
+
+#define REVERSIBLE_CC_MODE(MODE) 1
+
+/* A C expression whose value is reversed condition code of the CODE for
+   comparison done in CC_MODE mode.  */
+#define REVERSE_CONDITION(CODE, MODE) \
+  ((MODE) != CCFPmode && (MODE) != CCFPUmode ? reverse_condition (CODE) \
+   : reverse_condition_maybe_unordered (CODE))
+
 
 /* Control the assembler format that we output, to the extent
    this does not vary between assemblers.  */
@@ -2842,10 +2854,13 @@ do { long l;						\
   {"nonmemory_no_elim_operand", {CONST_INT, REG, SUBREG}},		\
   {"q_regs_operand", {SUBREG, REG}},					\
   {"non_q_regs_operand", {SUBREG, REG}},				\
-  {"fcmov_comparison_operator", {EQ, NE, LTU, GTU, LEU, GEU}},		\
+  {"fcmov_comparison_operator", {EQ, NE, LTU, GTU, LEU, GEU, UNORDERED, \
+				 ORDERED, LT, UNLT, GT, UNGT, LE, UNLE,	\
+				 GE, UNGE, LTGT, UNEQ}},		\
   {"sse_comparison_operator", {EQ, LT, LE, UNORDERED }},		\
   {"ix86_comparison_operator", {EQ, NE, LE, LT, GE, GT, LEU, LTU, GEU,	\
-			       GTU, UNORDERED, ORDERED}},		\
+			       GTU, UNORDERED, ORDERED, UNLE, UNLT,	\
+			       UNGE, UNGT, LTGT, UNEQ }},		\
   {"cmp_fp_expander_operand", {CONST_DOUBLE, SUBREG, REG, MEM}},	\
   {"ext_register_operand", {SUBREG, REG}},				\
   {"binary_fp_operator", {PLUS, MINUS, MULT, DIV}},			\

gcc/config/i386/i386.md

@@ -9304,14 +9304,12 @@
    (clobber (reg:CCFP 18))
    (clobber (reg:CCFP 17))]
   "reload_completed"
-  [(set (pc)
-	(if_then_else (match_dup 5)
-	  (match_dup 3)
-	  (match_dup 4)))]
+  [(const_int 0)]
   "
 {
-  operands[5] = ix86_expand_fp_compare (GET_CODE (operands[0]), operands[1],
-					operands[2], NULL_RTX);
+  ix86_split_fp_branch (operands[0], operands[1], operands[2],
+			operands[3], operands[4], NULL_RTX);
+  DONE;
 }")
 
 (define_split
@@ -9331,8 +9329,9 @@
 	  (match_dup 4)))]
   "
 {
-  operands[6] = ix86_expand_fp_compare (GET_CODE (operands[0]), operands[1],
-					operands[2], operands[5]);
+  ix86_split_fp_branch (operands[0], operands[1], operands[2],
+			operands[3], operands[4], operands[5]);
+  DONE;
 }")
 
 ;; Unconditional and other jump instructions

gcc/tm.texi

@@ -4857,6 +4857,21 @@ inequality comparisons are always given @code{CCFPEmode}:
 #define REVERSIBLE_CC_MODE(MODE)  ((MODE) != CCFPEmode)
 @end smallexample
 
+@findex REVERSE_CONDITION (@var{code}, @var{mode})
+A C expression whose value is reversed condition code of the @var{code} for
+comparison done in CC_MODE @var{mode}.  The macro is used only in case
+@code{REVERSIBLE_CC_MODE (@var{mode})} is nonzero.  Define this macro in case
+machine has some non-standard way how to reverse certain conditionals.  For
+instance in case all floating point conditions are non-trapping, compiler may
+freely convert unordered compares to ordered one.  Then definition may look
+like:
+
+@smallexample
+#define REVERSE_CONDITION(CODE, MODE) \
+   ((MODE) != CCFPmode ? reverse_condtion (CODE) \
+    : reverse_condition_maybe_unordered (CODE))
+@end smallexample
+
 @end table
 
 @node Costs