// System, string-primitive and x87 families: flag register moves, the
// serialising instructions, MOVS/STOS, the MXCSR pair, scalar float-to-int
// conversions and FMOVD.  Every result is folded back so no instruction is
// dead.

#include "textflag.h"

// func system(x uint64) uint64
TEXT ·system(SB), NOSPLIT, $0-16
	MOVQ    x+0(FP), AX
	PUSHFQ
	POPFQ
	CPUID
	RDTSC
	RDTSCP
	SYSCALL
	XGETBV
	PAUSE
	LFENCE
	MFENCE
	SFENCE
	UNDEF
	XORQ    AX, BX
	MOVQ    BX, ret+8(FP)
	RET

// func stringprim(p *byte, n int) uint64
TEXT ·stringprim(SB), NOSPLIT, $0-24
	MOVQ      p+0(FP), DI
	MOVQ      n+8(FP), CX
	LEAQ      buf<>(SB), AX
	MOVQ      AX, SI
	CLD
	MOVSB
	MOVSW
	MOVSL
	MOVSQ
	STOSB
	STOSQ
	STOSL
	STOSW
	MOVQ      DI, ret+16(FP)
	RET

DATA buf<>+0x00(SB)/8, $0

GLOBL buf<>(SB), NOPTR, $8

// func intgate(x uint64) uint64
TEXT ·intgate(SB), NOSPLIT, $0-16
	MOVQ    x+0(FP), AX
	INT     $3
	MOVQ    AX, ret+8(FP)
	RET

// func fpmxcsr(x float64, csr *uint32) int64
TEXT ·fpmxcsr(SB), NOSPLIT, $0-24
	MOVQ      x+0(FP), X0
	MOVQ      csr+8(FP), AX
	STMXCSR   (AX)
	LDMXCSR   (AX)
	CVTSD2SL  X0, CX
	CVTTSD2SQ X0, DX
	MOVL      (AX), SI
	MOVQ      SI, ret+8(FP)
	RET

// func fmove(p *float64) float64
TEXT ·fmove(SB), NOSPLIT, $0-16
	MOVQ  p+0(FP), AX
	FMOVD (AX), F0
	FMOVD F0, F1
	FMOVD F0, (AX)
	MOVQ  (AX), AX
	MOVQ  AX, ret+8(FP)
	RET