code review 124390043: go.sys/unix: just jump to syscall.Syscall etc.

unix/asm_darwin_386.s

Index: unix/asm_darwin_386.s
===================================================================
--- a/unix/asm_darwin_386.s
+++ b/unix/asm_darwin_386.s
@@ -2,141 +2,26 @@
 // 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, Darwin
 //
 
-// func Syscall(trap int32, a1, a2, a3 int32) (r1, r2, err int32);
-// func Syscall6(trap int32, a1, a2, a3, a4, a5, a6 int32) (r1, r2, err int32);
-// Trap # in AX, args on stack above caller pc.
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
 
 TEXT	·Syscall(SB),NOSPLIT,$0-28
-	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	$0x80
-	JAE	ok
-	MOVL	$-1, 20(SP)	// r1
-	MOVL	$-1, 24(SP)	// r2
-	MOVL	AX, 28(SP)		// errno
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok:
-	MOVL	AX, 20(SP)	// r1
-	MOVL	DX, 24(SP)	// r2
-	MOVL	$0, 28(SP)	// errno
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall(SB)
 
 TEXT	·Syscall6(SB),NOSPLIT,$0-40
-	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	$0x80
-	JAE	ok6
-	MOVL	$-1, 32(SP)	// r1
-	MOVL	$-1, 36(SP)	// r2
-	MOVL	AX, 40(SP)		// errno
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok6:
-	MOVL	AX, 32(SP)	// r1
-	MOVL	DX, 36(SP)	// r2
-	MOVL	$0, 40(SP)	// errno
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall6(SB)
 
 TEXT	·Syscall9(SB),NOSPLIT,$0-52
-	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
-	MOVSL
-	MOVSL
-	MOVSL
-	INT	$0x80
-	JAE	ok9
-	MOVL	$-1, 44(SP)	// r1
-	MOVL	$-1, 48(SP)	// r2
-	MOVL	AX, 52(SP)		// errno
-	CALL	runtime·exitsyscall(SB)
-	RET
-ok9:
-	MOVL	AX, 44(SP)	// r1
-	MOVL	DX, 48(SP)	// r2
-	MOVL	$0, 52(SP)	// errno
-	CALL	runtime·exitsyscall(SB)
-	RET
+	JMP	syscall·Syscall9(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	$0x80
-	JAE	ok1
-	MOVL	$-1, 20(SP)	// r1
-	MOVL	$-1, 24(SP)	// r2
-	MOVL	AX, 28(SP)		// errno
-	RET
-ok1:
-	MOVL	AX, 20(SP)	// r1
-	MOVL	DX, 24(SP)	// r2
-	MOVL	$0, 28(SP)	// errno
-	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	$0x80
-	JAE	ok2
-	MOVL	$-1, 32(SP)	// r1
-	MOVL	$-1, 36(SP)	// r2
-	MOVL	AX, 40(SP)		// errno
-	RET
-ok2:
-	MOVL	AX, 32(SP)	// r1
-	MOVL	DX, 36(SP)	// r2
-	MOVL	$0, 40(SP)	// errno
-	RET
+	JMP	syscall·RawSyscall6(SB)