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Commit 9ae9feba authored by Avi Kivity's avatar Avi Kivity Committed by Marcelo Tosatti
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KVM: x86 emulator: covert SETCC to fastop 



This is a bit of a special case since we don't have the usual
byte/word/long/quad switch; instead we switch on the condition code embedded
in the instruction.

Reviewed-by: default avatarGleb Natapov <gleb@redhat.com>
Signed-off-by: default avatarAvi Kivity <avi.kivity@gmail.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 007a3b54

arch/x86/kvm/emulate.c

+29 −31
Original line number Diff line number Diff line
@@ -499,6 +499,28 @@ static void invalidate_registers(struct x86_emulate_ctxt *ctxt) 
	ON64(FOP3E(op##q, rax, rbx, cl)) \

	FOP_END



/* Special case for SETcc - 1 instruction per cc */

#define FOP_SETCC(op) ".align 4; " #op " %al; ret \n\t"



FOP_START(setcc)

FOP_SETCC(seto)

FOP_SETCC(setno)

FOP_SETCC(setc)

FOP_SETCC(setnc)

FOP_SETCC(setz)

FOP_SETCC(setnz)

FOP_SETCC(setbe)

FOP_SETCC(setnbe)

FOP_SETCC(sets)

FOP_SETCC(setns)

FOP_SETCC(setp)

FOP_SETCC(setnp)

FOP_SETCC(setl)

FOP_SETCC(setnl)

FOP_SETCC(setle)

FOP_SETCC(setnle)

FOP_END;



#define __emulate_1op_rax_rdx(ctxt, _op, _suffix, _ex)			\

	do {								\

		unsigned long _tmp;					\
@@ -939,39 +961,15 @@ static int read_descriptor(struct x86_emulate_ctxt *ctxt, 
	return rc;

}



static int test_cc(unsigned int condition, unsigned int flags)

static u8 test_cc(unsigned int condition, unsigned long flags)

{

	int rc = 0;

	u8 rc;

	void (*fop)(void) = (void *)em_setcc + 4 * (condition & 0xf);



	switch ((condition & 15) >> 1) {

	case 0: /* o */

		rc |= (flags & EFLG_OF);

		break;

	case 1: /* b/c/nae */

		rc |= (flags & EFLG_CF);

		break;

	case 2: /* z/e */

		rc |= (flags & EFLG_ZF);

		break;

	case 3: /* be/na */

		rc |= (flags & (EFLG_CF|EFLG_ZF));

		break;

	case 4: /* s */

		rc |= (flags & EFLG_SF);

		break;

	case 5: /* p/pe */

		rc |= (flags & EFLG_PF);

		break;

	case 7: /* le/ng */

		rc |= (flags & EFLG_ZF);

		/* fall through */

	case 6: /* l/nge */

		rc |= (!(flags & EFLG_SF) != !(flags & EFLG_OF));

		break;

	}



	/* Odd condition identifiers (lsb == 1) have inverted sense. */

	return (!!rc ^ (condition & 1));

	flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF;

	asm("pushq %[flags]; popf; call *%[fastop]"

	    : "=a"(rc) : [fastop]"r"(fop), [flags]"r"(flags));

	return rc;

}



static void fetch_register_operand(struct operand *op)