[AArch64] Fix shrinkwrapping interactions with atomics (PR92692)

The separate shrinkwrapping pass may insert stores in the middle
of atomics loops which can cause issues on some implementations.
Avoid this by delaying splitting atomics patterns until after
prolog/epilog generation.

gcc/
	PR target/92692
	* config/aarch64/aarch64.c (aarch64_split_compare_and_swap)
	Add assert to ensure prolog has been emitted.
	(aarch64_split_atomic_op): Likewise.
	* config/aarch64/atomics.md (aarch64_compare_and_swap<mode>)
	Use epilogue_completed rather than reload_completed.
	(aarch64_atomic_exchange<mode>): Likewise.
	(aarch64_atomic_<atomic_optab><mode>): Likewise.
	(atomic_nand<mode>): Likewise.
	(aarch64_atomic_fetch_<atomic_optab><mode>): Likewise.
	(atomic_fetch_nand<mode>): Likewise.
	(aarch64_atomic_<atomic_optab>_fetch<mode>): Likewise.
	(atomic_nand_fetch<mode>): Likewise.
This commit is contained in:
Wilco Dijkstra 2020-01-17 13:17:21 +00:00
parent f788c2d66a
commit e5e07b6818
3 changed files with 32 additions and 10 deletions

View File

@ -1,3 +1,19 @@
2020-01-17 Wilco Dijkstra <wdijkstr@arm.com>
PR target/92692
* config/aarch64/aarch64.c (aarch64_split_compare_and_swap)
Add assert to ensure prolog has been emitted.
(aarch64_split_atomic_op): Likewise.
* config/aarch64/atomics.md (aarch64_compare_and_swap<mode>)
Use epilogue_completed rather than reload_completed.
(aarch64_atomic_exchange<mode>): Likewise.
(aarch64_atomic_<atomic_optab><mode>): Likewise.
(atomic_nand<mode>): Likewise.
(aarch64_atomic_fetch_<atomic_optab><mode>): Likewise.
(atomic_fetch_nand<mode>): Likewise.
(aarch64_atomic_<atomic_optab>_fetch<mode>): Likewise.
(atomic_nand_fetch<mode>): Likewise.
2020-01-17 Richard Sandiford <richard.sandiford@arm.com>
PR target/93133

View File

@ -18375,6 +18375,9 @@ aarch64_emit_post_barrier (enum memmodel model)
void
aarch64_split_compare_and_swap (rtx operands[])
{
/* Split after prolog/epilog to avoid interactions with shrinkwrapping. */
gcc_assert (epilogue_completed);
rtx rval, mem, oldval, newval, scratch, x, model_rtx;
machine_mode mode;
bool is_weak;
@ -18469,6 +18472,9 @@ void
aarch64_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
rtx value, rtx model_rtx, rtx cond)
{
/* Split after prolog/epilog to avoid interactions with shrinkwrapping. */
gcc_assert (epilogue_completed);
machine_mode mode = GET_MODE (mem);
machine_mode wmode = (mode == DImode ? DImode : SImode);
const enum memmodel model = memmodel_from_int (INTVAL (model_rtx));

View File

@ -56,7 +56,7 @@
(clobber (match_scratch:SI 7 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_compare_and_swap (operands);
@ -80,7 +80,7 @@
(clobber (match_scratch:SI 7 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_compare_and_swap (operands);
@ -104,7 +104,7 @@
(clobber (match_scratch:SI 7 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_compare_and_swap (operands);
@ -223,7 +223,7 @@
(clobber (match_scratch:SI 4 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (SET, operands[0], NULL, operands[1],
@ -344,7 +344,7 @@
(clobber (match_scratch:SI 4 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (<CODE>, NULL, operands[3], operands[0],
@ -400,7 +400,7 @@
(clobber (match_scratch:SI 4 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (NOT, NULL, operands[3], operands[0],
@ -504,7 +504,7 @@
(clobber (match_scratch:SI 5 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (<CODE>, operands[0], operands[4], operands[1],
@ -551,7 +551,7 @@
(clobber (match_scratch:SI 5 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (NOT, operands[0], operands[4], operands[1],
@ -604,7 +604,7 @@
(clobber (match_scratch:SI 4 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (<CODE>, NULL, operands[0], operands[1],
@ -628,7 +628,7 @@
(clobber (match_scratch:SI 4 "=&r"))]
""
"#"
"&& reload_completed"
"&& epilogue_completed"
[(const_int 0)]
{
aarch64_split_atomic_op (NOT, NULL, operands[0], operands[1],