pa.md (return): Revise comment for trivial return.

* pa.md (return): Revise comment for trivial return.
        (return_internal): Non-trivial return pattern for non-PIC code.
        (return_internal_pic): Non-trivial return pattern for PIC code.
        It uses the PIC register to ensure it is restored after
        function calls.
        (epilogue): Generate appropriate return for PIC and non-PIC code.

Co-Authored-By: Jeff Law <law@redhat.com>

From-SVN: r39345
This commit is contained in:
John David Anglin 2001-01-30 05:18:50 +00:00 committed by Jeff Law
parent 05d9f8b08c
commit 7ea9fcc649
2 changed files with 34 additions and 10 deletions

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@ -1,3 +1,13 @@
2001-01-29 John David Anglin <dave@hiauly1.hia.nrc.ca>
Jeff Law <law@redhat.com>
* pa.md (return): Revise comment for trivial return.
(return_internal): Non-trivial return pattern for non-PIC code.
(return_internal_pic): Non-trivial return pattern for PIC code.
It uses the PIC register to ensure it is restored after
function calls.
(epilogue): Generate appropriate return for PIC and non-PIC code.
Mon Jan 29 23:53:14 2001 Christopher Faylor <cgf@cygnus.com>
* config/i386/cygwin.h: Fix -mno-cygwin search path for link.

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@ -5467,7 +5467,7 @@
;; Unconditional and other jump instructions.
;; This can only be used in a leaf function, so we do
;; not need to use the PIC register.
;; not need to use the PIC register when generating PIC code.
(define_insn "return"
[(return)
(use (reg:SI 2))
@ -5482,18 +5482,29 @@
[(set_attr "type" "branch")
(set_attr "length" "4")])
;; Use a different pattern for functions which have non-trivial
;; Emit a different pattern for functions which have non-trivial
;; epilogues so as not to confuse jump and reorg.
;;
;; We use the PIC register to ensure it's restored after a
;; call in PIC mode. This can be non-optimal for non-PIC
;; code but the real world cost should be unmeasurable.
(define_insn "return_internal"
[(return)
(use (match_operand 0 "register_operand" "r"))
(use (reg:SI 2))
(const_int 1)]
"true_regnum (operands[0]) == PIC_OFFSET_TABLE_REGNUM"
"! flag_pic"
"*
{
if (TARGET_PA_20)
return \"bve%* (%%r2)\";
return \"bv%* %%r0(%%r2)\";
}"
[(set_attr "type" "branch")
(set_attr "length" "4")])
;; Use the PIC register to ensure it's restored after a
;; call in PIC mode.
(define_insn "return_internal_pic"
[(return)
(use (match_operand 0 "register_operand" "r"))
(use (reg:SI 2))]
"flag_pic && true_regnum (operands[0]) == PIC_OFFSET_TABLE_REGNUM"
"*
{
if (TARGET_PA_20)
@ -5531,8 +5542,11 @@
rtx x;
hppa_expand_epilogue ();
x = gen_return_internal (gen_rtx_REG (word_mode,
PIC_OFFSET_TABLE_REGNUM));
if (flag_pic)
x = gen_return_internal_pic (gen_rtx_REG (word_mode,
PIC_OFFSET_TABLE_REGNUM));
else
x = gen_return_internal ();
emit_jump_insn (x);
}
DONE;