avr.c (avr_case_values_threshold): New.

	* config/avr/avr.c (avr_case_values_threshold): New.
	(avr_override_options): Set it depending on options, make it large
	when not optimizing to work around "unable to generate reloads".

	* config/avr/avr.h (TARGET_SWITCHES): Add -mno-tablejump option.
	(EXTRA_SECTION_FUNCTIONS): Make the .progmem.gcc_sw_table section
	executable if not AVR_MEGA.  Make sure jump tables are word-aligned.
	(JUMP_TABLES_IN_TEXT_SECTION): Define as 0, not 1.
	(ASM_OUTPUT_ADDR_VEC_ELT): Optimize, use "rjmp" if not AVR_MEGA.
	(avr_case_values_threshold): Declare as extern int.
	(CASE_VALUES_THRESHOLD): Define as avr_case_values_threshold.

	* config/avr/avr.md (tablejump): Removed.
	(*tablejump_rjmp): New for jump tables made from "rjmp" instructions.
	(*tablejump_lib, *tablejump_enh, *tablejump): Change to expect the
	index in the table, not multiplied by 2.
	(casesi): Change to match the above insns.  Always enable.

	* config/avr/libgcc.S (__tablejump__): Rename to __tablejump2__.
	Change to expect the word address of the table, multiply it by 2
	here and not in the caller.  Change "adiw" to faster "inc".

From-SVN: r37465

gcc/ChangeLog

+Tue Nov 14 21:54:31 2000  Marek Michalkiewicz  <marekm@linux.org.pl> & Denis Chertykov  <denisc@overta.ru>
+
+	* config/avr/avr.c (avr_case_values_threshold): New.
+	(avr_override_options): Set it depending on options, make it large
+	when not optimizing to work around "unable to generate reloads".
+
+	* config/avr/avr.h (TARGET_SWITCHES): Add -mno-tablejump option.
+	(EXTRA_SECTION_FUNCTIONS): Make the .progmem.gcc_sw_table section
+	executable if not AVR_MEGA.  Make sure jump tables are word-aligned.
+	(JUMP_TABLES_IN_TEXT_SECTION): Define as 0, not 1.
+	(ASM_OUTPUT_ADDR_VEC_ELT): Optimize, use "rjmp" if not AVR_MEGA.
+	(avr_case_values_threshold): Declare as extern int.
+	(CASE_VALUES_THRESHOLD): Define as avr_case_values_threshold.
+
+	* config/avr/avr.md (tablejump): Removed.
+	(*tablejump_rjmp): New for jump tables made from "rjmp" instructions.
+	(*tablejump_lib, *tablejump_enh, *tablejump): Change to expect the
+	index in the table, not multiplied by 2.
+	(casesi): Change to match the above insns.  Always enable.
+
+	* config/avr/libgcc.S (__tablejump__): Rename to __tablejump2__.
+	Change to expect the word address of the table, multiply it by 2
+	here and not in the caller.  Change "adiw" to faster "inc".
+
 2000-11-14  Neil Booth  <neilb@earthling.net>
 
 	* cppexp.c (parse_defined): Call cpp_get_token not

gcc/config/avr/avr.c

@@ -160,6 +160,8 @@ static const struct mcu_type_s avr_mcu_types[] = {
   { NULL, 0 }
 };
 
+int avr_case_values_threshold = 30000;
+
 void
 avr_override_options ()
 {
@@ -188,6 +190,9 @@ avr_override_options ()
       case AVR4: avr_enhanced_p = 1; avr_mega_p = 0; break;
       case AVR5: avr_enhanced_p = 1; avr_mega_p = 1; break;
     }
+
+  if (optimize && !TARGET_NO_TABLEJUMP)
+    avr_case_values_threshold = (!AVR_MEGA || TARGET_CALL_PROLOGUES) ? 8 : 17;
 }
 
 

gcc/config/avr/avr.h

@@ -51,6 +51,7 @@ extern int target_flags;
 #define MASK_ORDER_1		0x00001000
 #define MASK_INSN_SIZE_DUMP	0x00002000
 #define MASK_ORDER_2		0x00004000
+#define MASK_NO_TABLEJUMP	0x00008000
 #define MASK_INT8		0x00010000
 #define MASK_NO_INTERRUPTS	0x00020000
 #define MASK_CALL_PROLOGUES	0x00040000
@@ -63,6 +64,7 @@ extern int target_flags;
 #define TARGET_INSN_SIZE_DUMP	(target_flags & MASK_INSN_SIZE_DUMP)
 #define TARGET_CALL_PROLOGUES	(target_flags & MASK_CALL_PROLOGUES)
 #define TARGET_TINY_STACK	(target_flags & MASK_TINY_STACK)
+#define TARGET_NO_TABLEJUMP	(target_flags & MASK_NO_TABLEJUMP)
 
 /* Dump each assembler insn's rtl into the output file.
    This is for debugging the compiler itself.  */
@@ -102,6 +104,8 @@ extern int target_flags;
     N_("Use subroutines for function prologue/epilogue") },		\
   { "tiny-stack", MASK_TINY_STACK,					\
     N_("Change only the low 8 bits of the stack pointer") },		\
+  { "no-tablejump", MASK_NO_TABLEJUMP,					\
+    N_("Do not generate tablejump insns") },				\
   { "rtl", MASK_RTL_DUMP, NULL },					\
   { "size", MASK_INSN_SIZE_DUMP,					\
     N_("Output instruction sizes to the asm file") },			\
@@ -2001,7 +2005,10 @@ progmem_section (void)							      \
   if (in_section != in_progmem)						      \
     {									      \
       fprintf (asm_out_file,						      \
-	       ".section .progmem.gcc_sw_table, \"a\", @progbits\n");	      \
+	       "\t.section .progmem.gcc_sw_table, \"%s\", @progbits\n",	      \
+	       AVR_MEGA ? "a" : "ax"); 					      \
+      /* Should already be aligned, this is just to be safe if it isn't.  */  \
+      fprintf (asm_out_file, "\t.p2align 1\n");				      \
       in_section = in_progmem;						      \
     }									      \
 }
@@ -2042,7 +2049,7 @@ progmem_section (void)							      \
    Do not define this macro if you put all constants in the read-only
    data section.  */
 
-#define JUMP_TABLES_IN_TEXT_SECTION 1
+#define JUMP_TABLES_IN_TEXT_SECTION 0
 /* Define this macro if jump tables (for `tablejump' insns) should be
    output in the text section, along with the assembler instructions.
    Otherwise, the readonly data section is used.
@@ -2705,8 +2712,13 @@ sprintf (STRING, "*.%s%d", PREFIX, NUM)
    pop hard register number REGNO off of the stack.  The code need
    not be optimal, since this macro is used only when profiling.  */
 
-#define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE)				      \
-  fprintf (STREAM, "\t.word pm(.L%d)\n", VALUE);
+#define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE)		\
+do {							\
+  if (AVR_MEGA)						\
+    fprintf (STREAM, "\t.word pm(.L%d)\n", VALUE);	\
+  else							\
+    fprintf (STREAM, "\trjmp .L%d\n", VALUE);		\
+} while (0)
 /* This macro should be provided on machines where the addresses in a
    dispatch table are absolute.
 
@@ -2761,7 +2773,9 @@ fprintf (STREAM, "\t.skip %d,0\n", n)
 /* An alias for a machine mode name.  This is the machine mode that
    elements of a jump-table should have.  */
 
-#define CASE_VALUES_THRESHOLD 17
+extern int avr_case_values_threshold;
+
+#define CASE_VALUES_THRESHOLD avr_case_values_threshold
 /* `CASE_VALUES_THRESHOLD'
    Define this to be the smallest number of different values for
    which it is best to use a jump-table instead of a tree of

gcc/config/avr/avr.md

@@ -1852,41 +1852,53 @@
 (define_expand "tablejump"
   [(parallel [(set (pc) (match_operand:HI 0 "register_operand" ""))
 	      (use (label_ref (match_operand 1 "" "")))])]
-  "optimize"
+  "0 && optimize"
   "")
 
+;; Note: the (mem:HI (...)) memory references here are special - actually
+;; the data is read from a word address in program memory (r31:r30 is the
+;; index in the table, not multiplied by 2 - see the "casesi" pattern).
+
+;; Table made from "rjmp" instructions for <=8K devices.
+(define_insn "*tablejump_rjmp"
+   [(set (pc) (mem:HI
+	       (plus:HI (match_operand:HI 0 "register_operand" "=&z")
+			(label_ref (match_operand 2 "" "")))))
+    (use (label_ref (match_operand 1 "" "")))]
+  "!AVR_MEGA"
+  "subi r30,pm_lo8(-(%2))
+	sbci r31,pm_hi8(-(%2))
+	ijmp"
+  [(set_attr "length" "3")
+   (set_attr "cc" "clobber")])
+
 ;; Not a prologue, but similar idea - move the common piece of code to libgcc.
 (define_insn "*tablejump_lib"
    [(set (pc) (mem:HI (plus:HI (match_operand:HI 0 "register_operand" "=&z")
 			       (label_ref (match_operand 2 "" "")))))
     (use (label_ref (match_operand 1 "" "")))]
-  "TARGET_CALL_PROLOGUES"
-  "*{
-  output_asm_insn (AS2 (subi,r30,lo8(-(%2))) CR_TAB
-	           AS2 (sbci,r31,hi8(-(%2))), operands);
-  return (AVR_MEGA
-          ? AS1 (jmp,__tablejump__)
-          : AS1 (rjmp,__tablejump__));
-  }"
-  [(set_attr "cc" "clobber")
-   (set (attr "length") (if_then_else (eq_attr "mcu_mega" "no")
-				      (const_int 3)
-				      (const_int 4)))])
-
+  "AVR_MEGA && TARGET_CALL_PROLOGUES"
+  "subi r30,pm_lo8(-(%2))
+	sbci r31,pm_hi8(-(%2))
+	jmp __tablejump2__"
+  [(set_attr "length" "4")
+   (set_attr "cc" "clobber")])
 
 (define_insn "*tablejump_enh"
    [(set (pc) (mem:HI
 	       (plus:HI (match_operand:HI 0 "register_operand" "=&z")
 			(label_ref (match_operand 2 "" "")))))
     (use (label_ref (match_operand 1 "" "")))]
-  "AVR_ENHANCED"
-  "subi r30,lo8(-(%2))
-	sbci r31,hi8(-(%2))
+  "AVR_MEGA && AVR_ENHANCED"
+  "subi r30,pm_lo8(-(%2))
+	sbci r31,pm_hi8(-(%2))
+	lsl r30
+	rol r31
 	lpm __tmp_reg__,Z+
 	lpm r31,Z
 	mov r30,__tmp_reg__
 	ijmp"
-  [(set_attr "length" "6")
+  [(set_attr "length" "8")
    (set_attr "cc" "clobber")])
 
 (define_insn "*tablejump"
@@ -1894,16 +1906,18 @@
 	       (plus:HI (match_operand:HI 0 "register_operand" "=&z")
 			(label_ref (match_operand 2 "" "")))))
     (use (label_ref (match_operand 1 "" "")))]
-  ""
-  "subi r30,lo8(-(%2))
-	sbci r31,hi8(-(%2))
+  "AVR_MEGA"
+  "subi r30,pm_lo8(-(%2))
+	sbci r31,pm_hi8(-(%2))
+	lsl r30
+	rol r31
 	lpm
+	inc r30
 	push r0
-	adiw r30,1
 	lpm
 	push r0
 	ret"
-  [(set_attr "length" "8")
+  [(set_attr "length" "10")
    (set_attr "cc" "clobber")])
 
 (define_expand "casesi"
@@ -1920,9 +1934,9 @@
 			   (const_int 0))
 		      (label_ref (match_operand 4 "" ""))
 		      (pc)))
-   (set (match_dup 6)
-	(plus:HI (match_dup 6)
-		 (match_dup 6)))
+;;   (set (match_dup 6)
+;;	(plus:HI (match_dup 6)
+;;		 (match_dup 6)))
 ;;   (set (match_dup 6)
 ;;	(plus:HI (match_dup 6) (label_ref (match_operand:HI 3 "" ""))))
 		 
@@ -1930,7 +1944,7 @@
 			 (plus:HI (match_dup 6)
 				  (label_ref (match_operand:HI 3 "" "")))))
 	      (use (label_ref (match_dup 3)))])]
-  "!optimize"
+  ""
   "
 {
   operands[6] = gen_reg_rtx (HImode);

gcc/config/avr/libgcc.S

@@ -691,9 +691,11 @@ _cleanup:
 #endif /* defined (L_cleanup) */
 
 #ifdef L_tablejump
-	.global __tablejump__
-	.func	__tablejump__
-__tablejump__:
+	.global __tablejump2__
+	.func	__tablejump2__
+__tablejump2__:
+	lsl	r30
+	rol	r31
 #if defined (__AVR_ENHANCED__)
 	lpm	__tmp_reg__, Z+
 	lpm	r31, Z
@@ -702,7 +704,7 @@ __tablejump__:
 #else
 	lpm
 	push	r0
-	adiw	r30, 1
+	inc	r30	; table is word aligned, no carry to high byte
 	lpm
 	push	r0
 	ret