From: miod <miod@openbsd.org>
Date: Fri, 2 Sep 2022 06:19:04 +0000 (+0000)
Subject: Use a shorter system call invocation template for system calls in the range
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=3e492f6eb5c9124bd14f3f57338f09e914ed8d63;p=openbsd

Use a shorter system call invocation template for system calls in the range
0-127, where immediate addressing can be used to load the system call number
in r0, rather than performing a memory load using pc-relative addressing.

No functional change, but rm(1) runs a couple cycles faster per file now.
---

diff --git a/lib/libc/arch/sh/SYS.h b/lib/libc/arch/sh/SYS.h
index 46bc22acf0a..bed791bab88 100644
--- a/lib/libc/arch/sh/SYS.h
+++ b/lib/libc/arch/sh/SYS.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: SYS.h,v 1.11 2016/05/18 20:21:13 guenther Exp $	*/
+/*	$OpenBSD: SYS.h,v 1.12 2022/09/02 06:19:04 miod Exp $	*/
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
  * All rights reserved.
@@ -85,14 +85,30 @@
 #define	__END(x)					\
 	__END_HIDDEN(x); SET_ENTRY_SIZE(x)
 
+#ifdef __ASSEMBLER__
+/*
+ * If the system call number fits in a 8-bit signed value (i.e. fits in 7 bits),
+ * then we can use the #imm8 addressing mode.
+ */
+
+.macro systrap num
+.iflt \num - 128
+	mov	# \num, r0
+	trapa	#0x80
+.else
+	mov.l	903f, r0
+	trapa	#0x80
+	bra	904f
+	 nop
+	.align	2
+ 903:	.long	\num
+ 904:
+.endif
+.endm
+#endif
+
 #define SYSTRAP(x)					\
-		mov.l	903f, r0;			\
-		.word	0xc380;	/* trapa #0x80; */	\
-		bra	904f;				\
-		 nop;					\
-		.align	2;				\
-	903:	.long	(SYS_ ## x);			\
-	904:
+		systrap	SYS_ ## x
 
 #define _SYSCALL_NOERROR(x,y)				\
 		SYSENTRY(x);				\
diff --git a/lib/libc/arch/sh/sys/brk.S b/lib/libc/arch/sh/sys/brk.S
index 9600546fa7c..4b854a31db5 100644
--- a/lib/libc/arch/sh/sys/brk.S
+++ b/lib/libc/arch/sh/sys/brk.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: brk.S,v 1.6 2016/05/30 05:18:52 guenther Exp $	*/
+/*	$OpenBSD: brk.S,v 1.7 2022/09/02 06:19:04 miod Exp $	*/
 /*	$NetBSD: brk.S,v 1.10 2006/01/06 03:58:31 uwe Exp $	*/
 
 /*-
@@ -64,7 +64,11 @@ ENTRY(brk)
 	bf	1f
 	mov	r0, r4
 1:
+#if SYS_break >= 128
 	mov.l	LSYS_break, r0
+#else
+	mov	#SYS_break, r0
+#endif
 	trapa	#0x80
 	bf	2f
 #ifdef __PIC__
@@ -81,7 +85,9 @@ ENTRY(brk)
 	SET_ERRNO_AND_RETURN
 
 	.align	2
+#if SYS_break >= 128
 LSYS_break:	.long	SYS_break
+#endif
 #ifdef __PIC__
 L_GOT:		.long	_GLOBAL_OFFSET_TABLE_
 Lminbrk:	.long	__minbrk@GOT
diff --git a/lib/libc/arch/sh/sys/sbrk.S b/lib/libc/arch/sh/sys/sbrk.S
index 4aaf07f2fde..3e569319700 100644
--- a/lib/libc/arch/sh/sys/sbrk.S
+++ b/lib/libc/arch/sh/sys/sbrk.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sbrk.S,v 1.6 2016/05/30 05:18:52 guenther Exp $	*/
+/*	$OpenBSD: sbrk.S,v 1.7 2022/09/02 06:19:04 miod Exp $	*/
 /*	$NetBSD: sbrk.S,v 1.9 2006/01/06 03:58:31 uwe Exp $	*/
 
 /*-
@@ -64,7 +64,11 @@ ENTRY(sbrk)
 #endif
 	mov.l	@r0, r0
 	add	r0, r4
+#if SYS_break >= 128
 	mov.l	LSYS_break, r0
+#else
+	mov	#SYS_break, r0
+#endif
 	trapa	#0x80
 	bf	1f
 #ifdef __PIC__
@@ -81,7 +85,9 @@ ENTRY(sbrk)
 	SET_ERRNO_AND_RETURN
 
 	.align	2
+#if SYS_break >= 128
 LSYS_break:	.long	SYS_break
+#endif
 #ifdef __PIC__
 L_GOT:		.long	_GLOBAL_OFFSET_TABLE_
 Lcurbrk:	.long	__curbrk@GOT
diff --git a/lib/libc/arch/sh/sys/sigprocmask.S b/lib/libc/arch/sh/sys/sigprocmask.S
index 32ff2872b33..74bacc8ae85 100644
--- a/lib/libc/arch/sh/sys/sigprocmask.S
+++ b/lib/libc/arch/sh/sys/sigprocmask.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sigprocmask.S,v 1.5 2016/05/18 20:21:13 guenther Exp $	*/
+/*	$OpenBSD: sigprocmask.S,v 1.6 2022/09/02 06:19:04 miod Exp $	*/
 /*	$NetBSD: sigprocmask.S,v 1.6 2003/08/07 16:42:21 agc Exp $	*/
 
 /*-
@@ -46,7 +46,12 @@ SYSENTRY_HIDDEN(sigprocmask)
 	nop
 1:	mov.l	@r2, r2			/* fetch indirect ... */
 	mov	r2, r5			/* to new mask arg */
-2:	mov.l	LSYS_sigprocmask, r0
+2:	
+#if SYS_sigprocmask >= 128
+	mov.l	LSYS_sigprocmask, r0
+#else
+	mov	#SYS_sigprocmask, r0
+#endif
 	trapa	#0x80
 	bf	4f
 	mov	r6, r2			/* fetch old mask requested */
@@ -61,6 +66,8 @@ SYSENTRY_HIDDEN(sigprocmask)
 	SET_ERRNO_AND_RETURN
 
 	.align	2
+#if SYS_sigprocmask >= 128
 LSYS_sigprocmask:
 	.long	SYS_sigprocmask
+#endif
 SYSCALL_END_HIDDEN(sigprocmask)
diff --git a/lib/libc/arch/sh/sys/sigsuspend.S b/lib/libc/arch/sh/sys/sigsuspend.S
index 1d7927423fc..4e2dffbb7b0 100644
--- a/lib/libc/arch/sh/sys/sigsuspend.S
+++ b/lib/libc/arch/sh/sys/sigsuspend.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sigsuspend.S,v 1.4 2016/05/18 20:21:13 guenther Exp $	*/
+/*	$OpenBSD: sigsuspend.S,v 1.5 2022/09/02 06:19:04 miod Exp $	*/
 /*	$NetBSD: sigsuspend.S,v 1.5 2003/08/07 16:42:21 agc Exp $	*/
 
 /*-
@@ -41,11 +41,17 @@ SYSENTRY_HIDDEN(sigsuspend)
 	mov	r4, r0		/* fetch mask arg */
 	mov.l	@r0, r0		/* indirect to mask arg */
 	mov	r0, r4
+#if SYS_sigsuspend >= 128
 	mov.l	LSYS_sigsuspend, r0
+#else
+	mov	#SYS_sigsuspend, r0
+#endif
 	trapa	#0x80
 	SET_ERRNO_AND_RETURN
 
 	.align	2
+#if SYS_sigsuspend >= 128
 LSYS_sigsuspend:
 	.long	SYS_sigsuspend
+#endif
 SYSCALL_END_HIDDEN(sigsuspend)
diff --git a/lib/libc/arch/sh/sys/tfork_thread.S b/lib/libc/arch/sh/sys/tfork_thread.S
index c37efc94997..6a322fe2b3b 100644
--- a/lib/libc/arch/sh/sys/tfork_thread.S
+++ b/lib/libc/arch/sh/sys/tfork_thread.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tfork_thread.S,v 1.3 2016/05/18 20:21:13 guenther Exp $	*/
+/*	$OpenBSD: tfork_thread.S,v 1.4 2022/09/02 06:19:04 miod Exp $	*/
 
 /*
  * Copyright (c) 2007 Miodrag Vallat.
@@ -24,8 +24,12 @@
  *			r4			r5		   r6		r7
  */
 ENTRY(__tfork_thread)
+#if SYS___tfork >= 128
 	mov.l	.LSYS___tfork, r0
-	.word	0xc380		/* trapa #0x80 */
+#else
+	mov	#SYS___tfork, r0
+#endif
+	trapa	#0x80
 	bf	9f
 
 	tst	r0, r0
@@ -44,8 +48,12 @@ ENTRY(__tfork_thread)
 	jsr	@r6
 	 mov	r7, r4
 
+#if SYS___threxit >= 128
 	mov.l	.LSYS___threxit, r0
-	.word	0xc380		/* trapa #0x80 */
+#else
+	mov	#SYS___threxit, r0
+#endif
+	trapa	#0x80
 
 9:
 	/*
@@ -54,7 +62,11 @@ ENTRY(__tfork_thread)
 	SET_ERRNO_AND_RETURN
 
 	.align 2
+#if SYS___tfork >= 128
 .LSYS___tfork:	.long SYS___tfork
+#endif
+#if SYS___threxit >= 128
 .LSYS___threxit:	.long SYS___threxit
+#endif
 
 	SET_ENTRY_SIZE(__tfork_thread)
diff --git a/libexec/ld.so/sh/SYS.h b/libexec/ld.so/sh/SYS.h
index 12aecd690f2..f9062bf1b07 100644
--- a/libexec/ld.so/sh/SYS.h
+++ b/libexec/ld.so/sh/SYS.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: SYS.h,v 1.1 2017/08/27 21:59:52 deraadt Exp $ */
+/*	$OpenBSD: SYS.h,v 1.2 2022/09/02 06:19:05 miod Exp $ */
 
 /*
  * Copyright (c) 2006 Dale Rahn
@@ -29,14 +29,30 @@
 #include <machine/asm.h>
 #include <sys/syscall.h>
 
-#define SYSTRAP(x)					\
-	mov.l	903f, r0;				\
-	.word	0xc380;	/* trapa #0x80; */		\
-	bra	904f;					\
-	 nop;						\
-	.align	2;					\
- 903:	.long	(SYS_ ## x);				\
+#ifdef __ASSEMBLER__
+/*
+ * If the system call number fits in a 8-bit signed value (i.e. fits in 7 bits),
+ * then we can use the #imm8 addressing mode.
+ */
+
+.macro systrap num
+.iflt \num - 128
+	mov	# \num, r0
+	trapa	#0x80
+.else
+	mov.l	903f, r0
+	trapa	#0x80
+	bra	904f
+	 nop
+	.align	2
+ 903:	.long	\num
  904:
+.endif
+.endm
+#endif
+
+#define SYSTRAP(x)					\
+		systrap	SYS_ ## x
 
 #define DL_SYSCALL(n)					\
 	.global		__CONCAT(_dl_,n)		;\