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KVM: x86 emulator: clean up control flow in x86_emulate_insn()
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x86_emulate_insn() is full of things like

    if (rc != X86EMUL_CONTINUE)
        goto done;
    break;

consolidate all of those at the end of the switch statement.

Signed-off-by: Avi Kivity <avi@redhat.com>
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Avi Kivity committed Oct 24, 2010
1 parent a4d4a7c commit 7d9ddae
Showing 1 changed file with 7 additions and 57 deletions.
64 changes: 7 additions & 57 deletions arch/x86/kvm/emulate.c
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Original file line number Diff line number Diff line change
Expand Up @@ -3098,8 +3098,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0x07: /* pop es */
rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_ES);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x08 ... 0x0d:
or: /* or */
Expand All @@ -3117,8 +3115,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0x17: /* pop ss */
rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_SS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x18 ... 0x1d:
sbb: /* sbb */
Expand All @@ -3129,8 +3125,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0x1f: /* pop ds */
rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_DS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x20 ... 0x25:
and: /* and */
Expand All @@ -3157,18 +3151,12 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
case 0x58 ... 0x5f: /* pop reg */
pop_instruction:
rc = emulate_pop(ctxt, ops, &c->dst.val, c->op_bytes);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x60: /* pusha */
rc = emulate_pusha(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x61: /* popa */
rc = emulate_popa(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x63: /* movsxd */
if (ctxt->mode != X86EMUL_MODE_PROT64)
Expand Down Expand Up @@ -3255,8 +3243,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
}
case 0x8f: /* pop (sole member of Grp1a) */
rc = emulate_grp1a(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0x90 ... 0x97: /* nop / xchg reg, rax */
if (c->dst.addr.reg == &c->regs[VCPU_REGS_RAX])
Expand All @@ -3278,8 +3264,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
c->dst.addr.reg = &ctxt->eflags;
c->dst.bytes = c->op_bytes;
rc = emulate_popf(ctxt, ops, &c->dst.val, c->op_bytes);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xa6 ... 0xa7: /* cmps */
c->dst.type = OP_NONE; /* Disable writeback. */
Expand All @@ -3299,18 +3283,12 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
goto pop_instruction;
case 0xc4: /* les */
rc = emulate_load_segment(ctxt, ops, VCPU_SREG_ES);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xc5: /* lds */
rc = emulate_load_segment(ctxt, ops, VCPU_SREG_DS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xcb: /* ret far */
rc = emulate_ret_far(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xcc: /* int3 */
irq = 3;
Expand All @@ -3319,8 +3297,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
irq = c->src.val;
do_interrupt:
rc = emulate_int(ctxt, ops, irq);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xce: /* into */
if (ctxt->eflags & EFLG_OF) {
Expand All @@ -3330,9 +3306,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0xcf: /* iret */
rc = emulate_iret(ctxt, ops);

if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xd0 ... 0xd1: /* Grp2 */
emulate_grp2(ctxt);
Expand Down Expand Up @@ -3419,8 +3392,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0xf6 ... 0xf7: /* Grp3 */
rc = emulate_grp3(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xf8: /* clc */
ctxt->eflags &= ~EFLG_CF;
Expand Down Expand Up @@ -3453,8 +3424,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
case 0xfe: /* Grp4 */
grp45:
rc = emulate_grp45(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xff: /* Grp5 */
if (c->modrm_reg == 5)
Expand All @@ -3464,6 +3433,9 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
goto cannot_emulate;
}

if (rc != X86EMUL_CONTINUE)
goto done;

writeback:
rc = writeback(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
Expand Down Expand Up @@ -3545,8 +3517,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
switch (c->modrm_rm) {
case 1:
rc = kvm_fix_hypercall(ctxt->vcpu);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
default:
goto cannot_emulate;
Expand Down Expand Up @@ -3585,10 +3555,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0x05: /* syscall */
rc = emulate_syscall(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
else
goto writeback;
break;
case 0x06:
emulate_clts(ctxt->vcpu);
Expand Down Expand Up @@ -3665,17 +3631,9 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0x34: /* sysenter */
rc = emulate_sysenter(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
else
goto writeback;
break;
case 0x35: /* sysexit */
rc = emulate_sysexit(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
else
goto writeback;
break;
case 0x40 ... 0x4f: /* cmov */
c->dst.val = c->dst.orig_val = c->src.val;
Expand All @@ -3694,8 +3652,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0xa1: /* pop fs */
rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_FS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xa3:
bt: /* bt */
Expand All @@ -3713,8 +3669,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0xa9: /* pop gs */
rc = emulate_pop_sreg(ctxt, ops, VCPU_SREG_GS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xab:
bts: /* bts */
Expand Down Expand Up @@ -3745,22 +3699,16 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0xb2: /* lss */
rc = emulate_load_segment(ctxt, ops, VCPU_SREG_SS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xb3:
btr: /* btr */
emulate_2op_SrcV_nobyte("btr", c->src, c->dst, ctxt->eflags);
break;
case 0xb4: /* lfs */
rc = emulate_load_segment(ctxt, ops, VCPU_SREG_FS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xb5: /* lgs */
rc = emulate_load_segment(ctxt, ops, VCPU_SREG_GS);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
case 0xb6 ... 0xb7: /* movzx */
c->dst.bytes = c->op_bytes;
Expand Down Expand Up @@ -3825,12 +3773,14 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
break;
case 0xc7: /* Grp9 (cmpxchg8b) */
rc = emulate_grp9(ctxt, ops);
if (rc != X86EMUL_CONTINUE)
goto done;
break;
default:
goto cannot_emulate;
}

if (rc != X86EMUL_CONTINUE)
goto done;

goto writeback;

cannot_emulate:
Expand Down

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