FreeChainXenon/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

optabs.c (add_equal_note): Do not create self-referencing REG_EQUAL notes.

Browse source 
* optabs.c (add_equal_note): Do not create self-referencing REG_EQUAL
	notes.
	* fwprop.c (forward_propagate_and_simplify): Likewise.

From-SVN: r194054
This commit is contained in:
Steven Bosscher 2012-12-02 15:46:26 +00:00
parent fa967f341c
commit 853f8f1c1c
3 changed files with 22 additions and 22 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
gcc/ChangeLog
View file

@ -1,3 +1,9 @@
2012-12-02 Steven Bosscher <steven@gcc.gnu.org>
* optabs.c (add_equal_note): Do not create self-referencing REG_EQUAL
notes.
* fwprop.c (forward_propagate_and_simplify): Likewise.
2012-12-02 Steven Bosscher <steven@gcc.gnu.org>
* function.h (struct rtl_data): Remove epilogue_delay_list.

9
gcc/fwprop.c
View file

@ -1315,9 +1315,12 @@ forward_propagate_and_simplify (df_ref use, rtx def_insn, rtx def_set)
/* Do not replace an existing REG_EQUAL note if the insn is not
recognized. Either we're already replacing in the note, or we'll
separately try plugging the definition in the note and simplifying.
And only install a REQ_EQUAL note when the destination is a REG,
as the note would be invalid otherwise. */
set_reg_equal = (note == NULL_RTX && REG_P (SET_DEST (use_set)));
And only install a REQ_EQUAL note when the destination is a REG
that isn't mentioned in USE_SET, as the note would be invalid
otherwise. */
set_reg_equal = (note == NULL_RTX && REG_P (SET_DEST (use_set))
&& ! reg_mentioned_p (SET_DEST (use_set),
SET_SRC (use_set)));
}
if (GET_MODE (*loc) == VOIDmode)

29
gcc/optabs.c
View file

@ -170,14 +170,14 @@ optab_libfunc (optab optab, enum machine_mode mode)
If the last insn does not set TARGET, don't do anything, but return 1.
If a previous insn sets TARGET and TARGET is one of OP0 or OP1,
don't add the REG_EQUAL note but return 0. Our caller can then try
again, ensuring that TARGET is not one of the operands. */
If the last insn or a previous insn sets TARGET and TARGET is one of OP0
or OP1, don't add the REG_EQUAL note but return 0. Our caller can then
try again, ensuring that TARGET is not one of the operands. */
static int
add_equal_note (rtx insns, rtx target, enum rtx_code code, rtx op0, rtx op1)
{
rtx last_insn, insn, set;
rtx last_insn, set;
rtx note;
gcc_assert (insns && INSN_P (insns) && NEXT_INSN (insns));
@ -192,6 +192,12 @@ add_equal_note (rtx insns, rtx target, enum rtx_code code, rtx op0, rtx op1)
if (GET_CODE (target) == ZERO_EXTRACT)
return 1;
/* If TARGET is in OP0 or OP1, punt. We'd end up with a note referencing
a value changing in the insn, so the note would be invalid for CSE. */
if (reg_overlap_mentioned_p (target, op0)
|| (op1 && reg_overlap_mentioned_p (target, op1)))
return 0;
for (last_insn = insns;
NEXT_INSN (last_insn) != NULL_RTX;
last_insn = NEXT_INSN (last_insn))
@ -207,21 +213,6 @@ add_equal_note (rtx insns, rtx target, enum rtx_code code, rtx op0, rtx op1)
|| ! rtx_equal_p (XEXP (SET_DEST (set), 0), target)))
return 1;
/* If TARGET is in OP0 or OP1, check if anything in SEQ sets TARGET
besides the last insn. */
if (reg_overlap_mentioned_p (target, op0)
|| (op1 && reg_overlap_mentioned_p (target, op1)))
{
insn = PREV_INSN (last_insn);
while (insn != NULL_RTX)
{
if (reg_set_p (target, insn))
return 0;
insn = PREV_INSN (insn);
}
}
if (GET_RTX_CLASS (code) == RTX_UNARY)
switch (code)
{