From 9ae9febae9500a0a6f5ce29ee4b8d942b5332529 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Sat, 19 Jan 2013 19:51:52 +0200 Subject: [PATCH] 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: Gleb Natapov Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 60 ++++++++++++++++++++---------------------- 1 file changed, 29 insertions(+), 31 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a94b1d76f799..e13138dd073e 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -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) -- 2.30.2