This patch does better re-usage of __tablejump2__ from libgcc so that
switch/case statements with jump tables become smaller because the sequence
needs 6 to 9 words compared to 2 when JMPing to __tablejump2__.
Moreover, __tablejump2__ does no more rely in the content of EIND (by using
EIJMP) and uses RET instead.
The insn conditions of tablejump insns now are the same as in
avr_output_addr_vec_elt.
Ok for trunk?
Johann
* config/avr/avr.md (*tablejump_rjmp): Change insn condition to
!AVR_HAVE_JMP_CALL.
(*tablejump_lib): Change insn condition to AVR_HAVE_JMP_CALL.
(*tablejump_enh, *tablejump): Remove insns.
* config/avr/libgcc.S (__tablejump__): Use RET instead of EIND +
EIJM for indirect jump. Use LPM Z+ where available.
Index: config/avr/libgcc.S
===================================================================
--- config/avr/libgcc.S (revision 179744)
+++ config/avr/libgcc.S (working copy)
@@ -821,13 +821,17 @@ ENDF __tablejump2__
DEFUN __tablejump__
#if defined (__AVR_HAVE_LPMX__)
+#if defined (__AVR_HAVE_EIJMP_EICALL__)
+ lpm __tmp_reg__, Z+
+ push __tmp_reg__
+ lpm __tmp_reg__, Z
+ push __tmp_reg__
+ push __zero_reg__
+ ret
+#else
lpm __tmp_reg__, Z+
lpm r31, Z
mov r30, __tmp_reg__
-
-#if defined (__AVR_HAVE_EIJMP_EICALL__)
- eijmp
-#else
ijmp
#endif
Index: config/avr/avr.md
===================================================================
--- config/avr/avr.md (revision 179744)
+++ config/avr/avr.md (working copy)
@@ -3719,62 +3719,36 @@ (define_insn "*indirect_jump_avr6"
(set_attr "cc" "none")])
;; table jump
+;; For entries in jump table see avr_output_addr_vec_elt.
-;; Table made from "rjmp" instructions for <=8K devices.
+;; Table made from "rjmp .L<n>" instructions for <= 8K devices.
(define_insn "*tablejump_rjmp"
- [(set (pc) (unspec:HI [(match_operand:HI 0 "register_operand" "!z,*r")]
- UNSPEC_INDEX_JMP))
+ [(set (pc)
+ (unspec:HI [(match_operand:HI 0 "register_operand" "!z,*r")]
+ UNSPEC_INDEX_JMP))
(use (label_ref (match_operand 1 "" "")))
(clobber (match_dup 0))]
- "(!AVR_HAVE_JMP_CALL) && (!AVR_HAVE_EIJMP_EICALL)"
+ "!AVR_HAVE_JMP_CALL"
"@
ijmp
push %A0\;push %B0\;ret"
[(set_attr "length" "1,3")
(set_attr "cc" "none,none")])
-;; Not a prologue, but similar idea - move the common piece of code to libgcc.
+;; Move the common piece of code to libgcc.
+;; Table made from ".word gs(.L<n>)" addresses for > 8K devices.
+;; Read jump address from table and perform indirect jump.
(define_insn "*tablejump_lib"
- [(set (pc) (unspec:HI [(match_operand:HI 0 "register_operand" "z")]
- UNSPEC_INDEX_JMP))
+ [(set (pc)
+ (unspec:HI [(match_operand:HI 0 "register_operand" "z")]
+ UNSPEC_INDEX_JMP))
(use (label_ref (match_operand 1 "" "")))
(clobber (match_dup 0))]
- "AVR_HAVE_JMP_CALL && TARGET_CALL_PROLOGUES"
- "%~jmp __tablejump2__"
+ "AVR_HAVE_JMP_CALL"
+ "jmp __tablejump2__"
[(set_attr "length" "2")
(set_attr "cc" "clobber")])
-(define_insn "*tablejump_enh"
- [(set (pc) (unspec:HI [(match_operand:HI 0 "register_operand" "z")]
- UNSPEC_INDEX_JMP))
- (use (label_ref (match_operand 1 "" "")))
- (clobber (match_dup 0))]
- "AVR_HAVE_JMP_CALL && AVR_HAVE_LPMX"
- "lsl r30
- rol r31
- lpm __tmp_reg__,Z+
- lpm r31,Z
- mov r30,__tmp_reg__
- %!ijmp"
- [(set_attr "length" "6")
- (set_attr "cc" "clobber")])
-
-(define_insn "*tablejump"
- [(set (pc) (unspec:HI [(match_operand:HI 0 "register_operand" "z")]
- UNSPEC_INDEX_JMP))
- (use (label_ref (match_operand 1 "" "")))
- (clobber (match_dup 0))]
- "AVR_HAVE_JMP_CALL && !AVR_HAVE_EIJMP_EICALL"
- "lsl r30
- rol r31
- lpm
- inc r30
- push r0
- lpm
- push r0
- ret"
- [(set_attr "length" "8")
- (set_attr "cc" "clobber")])
(define_expand "casesi"
[(set (match_dup 6)
