go.sys/plan9: just jump to syscall.Syscall etc.

Don't re-implement these functions.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/124350045

Author: robpike

plan9/asm_plan9_386.s

@@ -2,163 +2,29 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// TODO(rsc): Rewrite all nn(SP) references into name+(nn-8)(FP)
-// so that go vet can check that they are correct.
-
 #include "textflag.h"
 
 //
 // System call support for 386, Plan 9
 //
 
-//func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err string)
-//func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err string)
-//func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
-//func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
 
-// Trap # in AX, args on stack above caller pc.
 TEXT	·Syscall(SB),NOSPLIT,$0-32
-	CALL	runtime·entersyscall(SB)
-	MOVL	4(SP), AX	// syscall entry
-	// slide args down on top of system call number
-	LEAL		8(SP), SI
-	LEAL		4(SP), DI
-	CLD
-	MOVSL
-	MOVSL
-	MOVSL
-	INT	$64
-	MOVL	AX, r1+20(SP)
-	MOVL	$0, r2+24(SP)
-	CMPL	AX, $-1
-	JNE	ok3
-
-	SUBL	$8, SP
-	CALL	runtime·errstr(SB)
-	MOVL	SP, SI
-	ADDL	$8, SP
-	JMP	copyresult3
-	
-ok3:
-	LEAL	runtime·emptystring(SB), SI	
-	
-copyresult3:
-	LEAL	err+28(SP), DI
-
-	CLD
-	MOVSL
-	MOVSL
-
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall(SB)
 
 TEXT	·Syscall6(SB),NOSPLIT,$0-44
-	CALL	runtime·entersyscall(SB)
-	MOVL	4(SP), AX	// syscall entry
-	// slide args down on top of system call number
-	LEAL		8(SP), SI
-	LEAL		4(SP), DI
-	CLD
-	MOVSL
-	MOVSL
-	MOVSL
-	MOVSL
-	MOVSL
-	MOVSL
-	INT	$64
-	MOVL	AX, r1+32(SP)
-	MOVL	$0, r2+36(SP)
-	CMPL	AX, $-1
-	JNE	ok4
-	
-	SUBL	$8, SP
-	CALL	runtime·errstr(SB)
-	MOVL	SP, SI
-	ADDL	$8, SP
-	JMP	copyresult4
-	
-ok4:
-	LEAL	runtime·emptystring(SB), SI
-	
-copyresult4:
-	LEAL	err+40(SP), DI
-
-	CLD
-	MOVSL
-	MOVSL
-
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall6(SB)
 
 TEXT ·RawSyscall(SB),NOSPLIT,$0-28
-	MOVL	4(SP), AX	// syscall entry
-	// slide args down on top of system call number
-	LEAL		8(SP), SI
-	LEAL		4(SP), DI
-	CLD
-	MOVSL
-	MOVSL
-	MOVSL
-	INT	$64
-	MOVL	AX, r1+20(SP)
-	MOVL	AX, r2+24(SP)
-	MOVL	AX, err+28(SP)
-	RET
+	JMP	syscall·RawSyscall(SB)
 
-TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
-	MOVL	4(SP), AX	// syscall entry
-	// slide args down on top of system call number
-	LEAL		8(SP), SI
-	LEAL		4(SP), DI
-	CLD
-	MOVSL
-	MOVSL
-	MOVSL
-	MOVSL
-	MOVSL
-	MOVSL
-	INT	$64
-	MOVL	AX, r1+32(SP)
-	MOVL	AX, r2+36(SP)
-	MOVL	AX, err+40(SP)		
-	RET
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)
 
-#define SYS_SEEK 39	/* from zsysnum_plan9_386.go */
-
-//func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
 TEXT ·seek(SB),NOSPLIT,$0-36
-	LEAL	newoffset+24(SP), AX
-	MOVL	AX, placeholder+4(SP)
-	
-	MOVL	$SYS_SEEK, AX	// syscall entry
-	INT	$64
-	
-	CMPL	AX, $-1
-	JNE	ok6
-	MOVL	AX, 24(SP)	// newoffset low
-	MOVL	AX, 28(SP)	// newoffset high
-	
-	SUBL	$8, SP
-	CALL	plan9·errstr(SB)
-	MOVL	SP, SI
-	ADDL	$8, SP	
-	JMP	copyresult6
-	
-ok6:
-	LEAL	runtime·emptystring(SB), SI
-	
-copyresult6:
-	LEAL	err+32(SP), DI
-
-	CLD
-	MOVSL
-	MOVSL
-	RET
+	JMP	syscall·seek(SB)
 
-//func exit(code int)
-// Import runtime·exit for cleanly exiting.
 TEXT ·exit(SB),NOSPLIT,$4-4
-	MOVL	code+0(FP), AX
-	MOVL	AX, 0(SP)
-	CALL	runtime·exit(SB)
-	RET
+	JMP	syscall·exit(SB)

plan9/asm_plan9_amd64.s

@@ -2,161 +2,29 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// TODO(rsc): Rewrite all nn(SP) references into name+(nn-8)(FP)
-// so that go vet can check that they are correct.
-
 #include "textflag.h"
 
 //
-// System call support for Plan 9
+// System call support for amd64, Plan 9
 //
 
-//func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err string)
-//func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err string)
-//func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
-//func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
 
 TEXT	·Syscall(SB),NOSPLIT,$0-64
-	CALL	runtime·entersyscall(SB)
-	MOVQ	8(SP), BP	// syscall entry
-	// slide args down on top of system call number
-	LEAQ	16(SP), SI
-	LEAQ	8(SP), DI
-	CLD
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	SYSCALL
-	MOVQ	AX, r1+40(SP)
-	MOVQ	$0, r2+48(SP)
-	CMPL	AX, $-1
-	JNE	ok3
-
-	SUBQ	$16, SP
-	CALL	runtime·errstr(SB)
-	MOVQ	SP, SI
-	ADDQ	$16, SP
-	JMP	copyresult3
-	
-ok3:
-	LEAQ	runtime·emptystring(SB), SI	
-	
-copyresult3:
-	LEAQ	err+56(SP), DI
-
-	CLD
-	MOVSQ
-	MOVSQ
-
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall(SB)
 
 TEXT	·Syscall6(SB),NOSPLIT,$0-88
-	CALL	runtime·entersyscall(SB)
-	MOVQ	8(SP), BP	// syscall entry
-	// slide args down on top of system call number
-	LEAQ		16(SP), SI
-	LEAQ		8(SP), DI
-	CLD
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	SYSCALL
-	MOVQ	AX, r1+64(SP)
-	MOVQ	$0, r2+72(SP)
-	CMPL	AX, $-1
-	JNE	ok4
-	
-	SUBQ	$16, SP
-	CALL	runtime·errstr(SB)
-	MOVQ	SP, SI
-	ADDQ	$16, SP
-	JMP	copyresult4
-	
-ok4:
-	LEAQ	runtime·emptystring(SB), SI
-	
-copyresult4:
-	LEAQ	err+80(SP), DI
-
-	CLD
-	MOVSQ
-	MOVSQ
-
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall6(SB)
 
 TEXT ·RawSyscall(SB),NOSPLIT,$0-56
-	MOVQ	8(SP), BP	// syscall entry
-	// slide args down on top of system call number
-	LEAQ		16(SP), SI
-	LEAQ		8(SP), DI
-	CLD
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	SYSCALL
-	MOVQ	AX, r1+40(SP)
-	MOVQ	AX, r2+48(SP)
-	MOVQ	AX, err+56(SP)
-	RET
+	JMP	syscall·RawSyscall(SB)
 
 TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
-	MOVQ	8(SP), BP	// syscall entry
-	// slide args down on top of system call number
-	LEAQ		16(SP), SI
-	LEAQ		8(SP), DI
-	CLD
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	MOVSQ
-	SYSCALL
-	MOVQ	AX, r1+64(SP)
-	MOVQ	AX, r2+72(SP)
-	MOVQ	AX, err+80(SP)		
-	RET
+	JMP	syscall·RawSyscall6(SB)
 
-#define SYS_SEEK 39	/* from zsysnum_plan9_amd64.go */
-
-//func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
 TEXT ·seek(SB),NOSPLIT,$0-56
-	LEAQ	newoffset+40(SP), AX
-	MOVQ	AX, placeholder+8(SP)
-	
-	MOVQ	$SYS_SEEK, BP	// syscall entry
-	SYSCALL
-	
-	CMPL	AX, $-1
-	JNE	ok6
-	MOVQ	$-1, newoffset+40(SP)
-	
-	SUBQ	$16, SP
-	CALL	plan9·errstr(SB)
-	MOVQ	SP, SI
-	ADDQ	$16, SP	
-	JMP	copyresult6
-	
-ok6:
-	LEAQ	runtime·emptystring(SB), SI
-	
-copyresult6:
-	LEAQ	err+48(SP), DI
-
-	CLD
-	MOVSQ
-	MOVSQ
-	RET
+	JMP	syscall·seek(SB)
 
-//func exit(code int)
-// Import runtime·exit for cleanly exiting.
 TEXT ·exit(SB),NOSPLIT,$8-8
-	MOVQ	code+0(FP), AX
-	MOVQ	AX, 0(SP)
-	CALL	runtime·exit(SB)
-	RET
+	JMP	syscall·exit(SB)