diff mbox series

[4/6] sh: Make *minus_plus_one work after RA

Message ID 20240620133418.350772-5-richard.sandiford@arm.com
State New
Headers show
Series Add a late-combine pass | expand

Commit Message

Richard Sandiford June 20, 2024, 1:34 p.m. UTC 
*minus_plus_one had no constraints, which meant that it could be
matched after RA with operands 0, 1 and 2 all being different.
The associated split instead requires operand 0 to be tied to
operand 1.

gcc/
	* config/sh/sh.md (*minus_plus_one): Add constraints.
---
 gcc/config/sh/sh.md | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Oleg Endo June 21, 2024, 12:15 a.m. UTC | #1 
On Thu, 2024-06-20 at 14:34 +0100, Richard Sandiford wrote:
> *minus_plus_one had no constraints, which meant that it could be
> matched after RA with operands 0, 1 and 2 all being different.
> The associated split instead requires operand 0 to be tied to
> operand 1.

Thanks for spotting this.  Makes sense, please install.

Best regards,
Oleg Endo

> 
> gcc/
> 	* config/sh/sh.md (*minus_plus_one): Add constraints.
> ---
>  gcc/config/sh/sh.md | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
> index 92a1efeb811..9491b49e55b 100644
> --- a/gcc/config/sh/sh.md
> +++ b/gcc/config/sh/sh.md
> @@ -1642,9 +1642,9 @@ (define_insn_and_split "*addc"
>  ;; matched.  Split this up into a simple sub add sequence, as this will save
>  ;; us one sett insn.
>  (define_insn_and_split "*minus_plus_one"
> -  [(set (match_operand:SI 0 "arith_reg_dest" "")
> -	(plus:SI (minus:SI (match_operand:SI 1 "arith_reg_operand" "")
> -			   (match_operand:SI 2 "arith_reg_operand" ""))
> +  [(set (match_operand:SI 0 "arith_reg_dest" "=r")
> +	(plus:SI (minus:SI (match_operand:SI 1 "arith_reg_operand" "0")
> +			   (match_operand:SI 2 "arith_reg_operand" "r"))
>  		 (const_int 1)))]
>    "TARGET_SH1"
>    "#"
> -- 
> 2.25.1
>
diff mbox series

Patch

diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
index 92a1efeb811..9491b49e55b 100644
--- a/gcc/config/sh/sh.md
+++ b/gcc/config/sh/sh.md
@@ -1642,9 +1642,9 @@  (define_insn_and_split "*addc"
 ;; matched.  Split this up into a simple sub add sequence, as this will save
 ;; us one sett insn.
 (define_insn_and_split "*minus_plus_one"
-  [(set (match_operand:SI 0 "arith_reg_dest" "")
-	(plus:SI (minus:SI (match_operand:SI 1 "arith_reg_operand" "")
-			   (match_operand:SI 2 "arith_reg_operand" ""))
+  [(set (match_operand:SI 0 "arith_reg_dest" "=r")
+	(plus:SI (minus:SI (match_operand:SI 1 "arith_reg_operand" "0")
+			   (match_operand:SI 2 "arith_reg_operand" "r"))
 		 (const_int 1)))]
   "TARGET_SH1"
   "#"