[PATCH] rtl-optimization/106082 - preserve EH note for no non-local goto

[PATCH] rtl-optimization/106082 - preserve EH note for no non-local goto

[Richard Biener]

The following makes sure we preserve EH notes on call insns that
indicate the call doesn't perform a non-local goto when distributing
notes after combining insns.

Bootstrap & regtest pending on x86_64-unknown-linux-gnu, tested on
the m68k testcase in the PR.

OK for trunk if testing passes?

Thanks,
Richard.

2022-06-28  Richard Biener  <rguenther@suse.de>

	PR rtl-optimization/106082
	* combine.cc (distribute_notes): Preserve notes when
	they indicate a call doesn't perform a non-local goto.
---
 gcc/combine.cc | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gcc/combine.cc b/gcc/combine.cc
index a8305273e44..3d34e860cf9 100644
--- a/gcc/combine.cc
+++ b/gcc/combine.cc
@@ -14218,8 +14218,10 @@ distribute_notes (rtx notes, rtx_insn *from_insn, rtx_insn *i3, rtx_insn *i2,
 	      gcc_assert (from_insn == i3);
 	    /* We are making sure there is a single effective REG_EH_REGION
 	       note and it's valid to put it on i3.  */
-	    if (!insn_could_throw_p (from_insn))
-	      /* Throw away stra notes on insns that can never throw.  */
+	    if (!insn_could_throw_p (from_insn)
+		&& (lp_nr != INT_MIN || !can_nonlocal_goto (from_insn)))
+	      /* Throw away stray notes on insns that can never throw or
+		 make a nonlocal goto.  */
 	      ;
 	    else
 	      {
-- 
2.35.3

[PATCH] rtl-optimization/106082 - preserve EH note for no non-local goto

[Richard Biener]

The following makes sure we preserve EH notes on call insns that
indicate the call doesn't perform a non-local goto when distributing
notes after combining insns.

Bootstrap & regtest pending on x86_64-unknown-linux-gnu, tested on
the m68k testcase in the PR.

OK for trunk if testing passes?

Thanks,
Richard.

2022-06-28  Richard Biener  <rguenther@suse.de>

	PR rtl-optimization/106082
	* combine.cc (distribute_notes): Preserve notes when
	they indicate a call doesn't perform a non-local goto.
---
 gcc/combine.cc | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gcc/combine.cc b/gcc/combine.cc
index a8305273e44..3d34e860cf9 100644
--- a/gcc/combine.cc
+++ b/gcc/combine.cc
@@ -14218,8 +14218,10 @@ distribute_notes (rtx notes, rtx_insn *from_insn, rtx_insn *i3, rtx_insn *i2,
 	      gcc_assert (from_insn == i3);
 	    /* We are making sure there is a single effective REG_EH_REGION
 	       note and it's valid to put it on i3.  */
-	    if (!insn_could_throw_p (from_insn))
-	      /* Throw away stra notes on insns that can never throw.  */
+	    if (!insn_could_throw_p (from_insn)
+		&& (lp_nr != INT_MIN || !can_nonlocal_goto (from_insn)))
+	      /* Throw away stray notes on insns that can never throw or
+		 make a nonlocal goto.  */
 	      ;
 	    else
 	      {
-- 
2.35.3

[PATCH] rtl-optimization/106082 - preserve EH note for no non-local goto

[Richard Biener]

The following makes sure we preserve EH notes on call insns that
indicate the call doesn't perform a non-local goto when distributing
notes after combining insns.

Bootstrap & regtest pending on x86_64-unknown-linux-gnu, tested on
the m68k testcase in the PR.

OK for trunk if testing passes?

Thanks,
Richard.

2022-06-28  Richard Biener  <rguenther@suse.de>

	PR rtl-optimization/106082
	* combine.cc (distribute_notes): Preserve notes when
	they indicate a call doesn't perform a non-local goto.
---
 gcc/combine.cc | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gcc/combine.cc b/gcc/combine.cc
index a8305273e44..3d34e860cf9 100644
--- a/gcc/combine.cc
+++ b/gcc/combine.cc
@@ -14218,8 +14218,10 @@ distribute_notes (rtx notes, rtx_insn *from_insn, rtx_insn *i3, rtx_insn *i2,
 	      gcc_assert (from_insn == i3);
 	    /* We are making sure there is a single effective REG_EH_REGION
 	       note and it's valid to put it on i3.  */
-	    if (!insn_could_throw_p (from_insn))
-	      /* Throw away stra notes on insns that can never throw.  */
+	    if (!insn_could_throw_p (from_insn)
+		&& (lp_nr != INT_MIN || !can_nonlocal_goto (from_insn)))
+	      /* Throw away stray notes on insns that can never throw or
+		 make a nonlocal goto.  */
 	      ;
 	    else
 	      {
-- 
2.35.3

Re: [PATCH] rtl-optimization/106082 - preserve EH note for no non-local goto

[Jeff Law]

On 6/28/2022 5:11 AM, Richard Biener wrote:
> The following makes sure we preserve EH notes on call insns that
> indicate the call doesn't perform a non-local goto when distributing
> notes after combining insns.
>
> Bootstrap & regtest pending on x86_64-unknown-linux-gnu, tested on
> the m68k testcase in the PR.
>
> OK for trunk if testing passes?
>
> Thanks,
> Richard.
>
> 2022-06-28  Richard Biener  <rguenther@suse.de>
>
> 	PR rtl-optimization/106082
> 	* combine.cc (distribute_notes): Preserve notes when
> 	they indicate a call doesn't perform a non-local goto.
I've thrown this into the tester and fired up a m68k run.  Results in 
~30hrs or so.

jeff

Re: [PATCH] rtl-optimization/106082 - preserve EH note for no non-local goto

[Segher Boessenkool]

On Tue, Jun 28, 2022 at 11:11:55AM +0000, Richard Biener wrote:
> The following makes sure we preserve EH notes on call insns that
> indicate the call doesn't perform a non-local goto when distributing
> notes after combining insns.

> -	    if (!insn_could_throw_p (from_insn))
> -	      /* Throw away stra notes on insns that can never throw.  */
> +	    if (!insn_could_throw_p (from_insn)
> +		&& (lp_nr != INT_MIN || !can_nonlocal_goto (from_insn)))
> +	      /* Throw away stray notes on insns that can never throw or
> +		 make a nonlocal goto.  */
>  	      ;

Where is the meaning of INT_MIN here documented?

... Ah, in except.cc .

Can you write this as

	    if (!insn_could_throw_p (from_insn)
		&& !(lp_nr == INT_MIN && can_nonlocal_goto (from_insn)))

please?  It is easier to understand that way.

With or without that, okay for trunk.  Thanks!


Segher