MOVQ	DI, BX
	CALL	libc_mach_absolute_time(SB)
	MOVQ	AX, 0(BX)
	MOVL	timebase<>+machTimebaseInfo_numer(SB), SI
	MOVL	timebase<>+machTimebaseInfo_denom(SB), DI // atomic read
	TESTL	DI, DI
	JNE	initialized

	SUBQ	$(machTimebaseInfo__size+15)/16*16, SP
	MOVQ	SP, DI
	CALL	libc_mach_timebase_info(SB)
	MOVL	machTimebaseInfo_numer(SP), SI
	MOVL	machTimebaseInfo_denom(SP), DI

aligned:
	MOVQ $0, AX // position in slices

	PCALIGN $16
loop16b:
	MOVOU (SI)(AX*1), X0   // XOR 16byte forwards.
	MOVOU (CX)(AX*1), X1
	PXOR  X1, X0
	MOVOU X0, (BX)(AX*1)
	ADDQ  $16, AX
	CMPQ  DX, AX
	JNE   loop16b
	RET

	PCALIGN $16
loop_1b:
	SUBQ  $1, DX           // XOR 1byte backwards.
	MOVB  (SI)(DX*1), DI
	MOVB  (CX)(DX*1), AX
	XORB  AX, DI
	MOVB  DI, (BX)(DX*1)

	// will clobber the test pattern created by the caller
	ADDL	$(1024 * 8), SP

	// Ask signaller to setgid
	MOVL	$1, (BX)

	// Wait for setgid completion
loop:
	PAUSE
	MOVL	(BX), AX
	CMPL	AX, $0
	JNE	loop

	// Restore stack
	SUBL	$(1024 * 8), SP

	MOVQ	trap+0(FP), BP	// syscall entry
	// copy args down
	LEAQ	a1+8(FP), SI
	LEAQ	sysargs-160(SP), DI
	CLD
	MOVSQ
	MOVSQ
	MOVSQ
	SYSCALL
	MOVQ	AX, r1+32(FP)
	MOVQ	$0, r2+40(FP)
	CMPL	AX, $-1
	JNE	ok3

	LEAQ	errbuf-128(SP), AX
	MOVQ	AX, sysargs-160(SP)
	MOVQ	$128, sysargs1-152(SP)
	MOVQ	$SYS_ERRSTR, BP
	SYSCALL
	CALL	runtime·exitsyscall(SB) // call via ABI wrapper, ensuring ABIInternal fixed registers are set

	MOVL	(_INTERRUPT_TIME+time_hi2), DI
	CMPL	AX, DI
	JNE	loop

	// w = DI:CX
	// multiply by 100
	MOVL	$100, AX
	MULL	CX
	IMULL	$100, DI
	ADDL	DI, DX
	// w*100 = DX:AX
	MOVL	AX, mono+12(FP)
	MOVL	DX, mono+16(FP)

wall:
	MOVL	(_SYSTEM_TIME+time_hi1), CX
	MOVL	(_SYSTEM_TIME+time_lo), AX
	MOVL	(_SYSTEM_TIME+time_hi2), DX
	CMPL	CX, DX
	JNE	wall

	// w = DX:AX

	MOVQ	8(BX), SI		// arg 2 len
	MOVL	16(BX), DX		// arg 3 prot
	MOVL	20(BX), CX		// arg 4 flags
	MOVL	24(BX), R8		// arg 5 fid
	MOVL	28(BX), R9		// arg 6 offset
	CALL	libc_mmap(SB)
	XORL	DX, DX
	CMPQ	AX, $-1
	JNE	ok
	CALL	libc_errno(SB)
	MOVLQSX	(AX), DX		// errno
	XORQ	AX, AX
ok:
	MOVQ	AX, 32(BX)
	MOVQ	DX, 40(BX)
	RET

TEXT runtime·munmap_trampoline(SB),NOSPLIT,$0
	MOVQ	8(DI), SI		// arg 2 len

	CMPL	CX, $0;	JE	_0args
	CMPL	CX, $1;	JE	_1args
	CMPL	CX, $2;	JE	_2args
	CMPL	CX, $3;	JE	_3args
	CMPL	CX, $4;	JE	_4args

	// Check we have enough room for args.
	CMPL	CX, $const_maxArgs
	JLE	2(PC)
	INT	$3			// not enough room -> crash

	// Copy args to the stack.
	MOVQ	SP, DI
	CLD
	REP; MOVSQ
	MOVQ	SP, SI

	// Load first 4 args into correspondent registers.

	"INVLPG",
	"INVPCID",
	"INW",
	"IRETL",
	"IRETQ",
	"IRETW",
	"JCC",
	"JCS",
	"JCXZL",
	"JCXZQ",
	"JCXZW",
	"JEQ",
	"JGE",
	"JGT",
	"JHI",
	"JLE",
	"JLS",
	"JLT",
	"JMI",
	"JNE",
	"JOC",
	"JOS",
	"JPC",
	"JPL",
	"JPS",
	"KADDB",
	"KADDD",
	"KADDQ",
	"KADDW",
	"KANDB",
	"KANDD",
	"KANDNB",
	"KANDND",
	"KANDNQ",
	"KANDNW",

	ADDQ	$(1024 * 8), SP

	// Ask signaller to setgid
	MOVL	$1, ·Baton(SB)

	// Wait for setgid completion
loop:
	PAUSE
	MOVL	·Baton(SB), AX
	CMPL	AX, $0
	JNE	loop

	// Restore stack
	SUBQ	$(1024 * 8), SP

	MOVQ R12, 8(R10)(SI*8)
	MOVQ R13, 16(R10)(SI*8)
	MOVQ R14, 24(R10)(SI*8)
	SBBQ CX, CX		// save CF

	ADDQ $4, SI		// i += 4
	SUBQ $4, DI		// n -= 4
	JGE U1			// if n >= 0 goto U1

V1:	ADDQ $4, DI		// n += 4
	JLE E1			// if n <= 0 goto E1

L1:	// n > 0
	ADDQ CX, CX		// restore CF
	MOVQ 0(R8)(SI*8), R11
	ADCQ 0(R9)(SI*8), R11
	MOVQ R11, 0(R10)(SI*8)
	SBBQ CX, CX		// save CF

	ADDQ $1, SI		// i++
	SUBQ $1, DI		// n--