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

re PR target/63483 (Scheduler performs Invalid move of aliased memory reference)

Browse source 
PR rtl-optimization/63483
	* alias.c (true_dependence_1): Do not exit early for MEM_READONLY_P
	references when alignment ANDs are involved.
	(write_dependence_p): Ditto.
	(may_alias_p): Ditto.

From-SVN: r216100
This commit is contained in:
Uros Bizjak 2014-10-10 19:36:21 +02:00 • committed by Uros Bizjak
parent 0e82f08971
commit 878f5596b3
2 changed files with 55 additions and 34 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
gcc/ChangeLog
View file

@ -1,3 +1,11 @@
2014-10-10 Uros Bizjak <ubizjak@gmail.com>
PR rtl-optimization/63483
* alias.c (true_dependence_1): Do not exit early for MEM_READONLY_P
references when alignment ANDs are involved.
(write_dependence_p): Ditto.
(may_alias_p): Ditto.
2014-10-10 Marek Polacek <polacek@redhat.com>
* asan.c (pass_sanopt::execute): Handle IFN_UBSAN_OBJECT_SIZE.

81
gcc/alias.c
View file

@ -2458,18 +2458,6 @@ true_dependence_1 (const_rtx mem, enum machine_mode mem_mode, rtx mem_addr,
|| MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
return 1;
/* Read-only memory is by definition never modified, and therefore can't
conflict with anything. We don't expect to find read-only set on MEM,
but stupid user tricks can produce them, so don't die. */
if (MEM_READONLY_P (x))
return 0;
/* If we have MEMs referring to different address spaces (which can
potentially overlap), we cannot easily tell from the addresses
whether the references overlap. */
if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
return 1;
if (! mem_addr)
{
mem_addr = XEXP (mem, 0);
@ -2493,6 +2481,22 @@ true_dependence_1 (const_rtx mem, enum machine_mode mem_mode, rtx mem_addr,
}
}
/* Read-only memory is by definition never modified, and therefore can't
conflict with anything. However, don't assume anything when AND
addresses are involved and leave to the code below to determine
dependence. We don't expect to find read-only set on MEM, but
stupid user tricks can produce them, so don't die. */
if (MEM_READONLY_P (x)
&& GET_CODE (x_addr) != AND
&& GET_CODE (mem_addr) != AND)
return 0;
/* If we have MEMs referring to different address spaces (which can
potentially overlap), we cannot easily tell from the addresses
whether the references overlap. */
if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
return 1;
base = find_base_term (x_addr);
if (base && (GET_CODE (base) == LABEL_REF
|| (GET_CODE (base) == SYMBOL_REF
@ -2576,16 +2580,6 @@ write_dependence_p (const_rtx mem,
|| MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
return 1;
/* A read from read-only memory can't conflict with read-write memory. */
if (!writep && MEM_READONLY_P (mem))
return 0;
/* If we have MEMs referring to different address spaces (which can
potentially overlap), we cannot easily tell from the addresses
whether the references overlap. */
if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
return 1;
mem_addr = XEXP (mem, 0);
if (!x_addr)
{
@ -2603,6 +2597,21 @@ write_dependence_p (const_rtx mem,
}
}
/* A read from read-only memory can't conflict with read-write memory.
Don't assume anything when AND addresses are involved and leave to
the code below to determine dependence. */
if (!writep
&& MEM_READONLY_P (mem)
&& GET_CODE (x_addr) != AND
&& GET_CODE (mem_addr) != AND)
return 0;
/* If we have MEMs referring to different address spaces (which can
potentially overlap), we cannot easily tell from the addresses
whether the references overlap. */
if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
return 1;
base = find_base_term (mem_addr);
if (! writep
&& base
@ -2690,18 +2699,6 @@ may_alias_p (const_rtx mem, const_rtx x)
|| MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
return 1;
/* Read-only memory is by definition never modified, and therefore can't
conflict with anything. We don't expect to find read-only set on MEM,
but stupid user tricks can produce them, so don't die. */
if (MEM_READONLY_P (x))
return 0;
/* If we have MEMs referring to different address spaces (which can
potentially overlap), we cannot easily tell from the addresses
whether the references overlap. */
if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
return 1;
x_addr = XEXP (x, 0);
mem_addr = XEXP (mem, 0);
if (!((GET_CODE (x_addr) == VALUE
@ -2715,6 +2712,22 @@ may_alias_p (const_rtx mem, const_rtx x)
mem_addr = get_addr (mem_addr);
}
/* Read-only memory is by definition never modified, and therefore can't
conflict with anything. However, don't assume anything when AND
addresses are involved and leave to the code below to determine
dependence. We don't expect to find read-only set on MEM, but
stupid user tricks can produce them, so don't die. */
if (MEM_READONLY_P (x)
&& GET_CODE (x_addr) != AND
&& GET_CODE (mem_addr) != AND)
return 0;
/* If we have MEMs referring to different address spaces (which can
potentially overlap), we cannot easily tell from the addresses
whether the references overlap. */
if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
return 1;
rtx x_base = find_base_term (x_addr);
rtx mem_base = find_base_term (mem_addr);
if (! base_alias_check (x_addr, x_base, mem_addr, mem_base,