KVM: x86 emulator: clean up control flow in x86_emulate_insn()

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>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 9940d16..27d2c22 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3098,8 +3098,6 @@ special_insn:
                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 */
@@ -3117,8 +3115,6 @@ special_insn:
                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 */
@@ -3129,8 +3125,6 @@ special_insn:
                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 */
@@ -3157,18 +3151,12 @@ special_insn:
        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)
@@ -3255,8 +3243,6 @@ special_insn:
        }
        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])
@@ -3278,8 +3264,6 @@ special_insn:
                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. */
@@ -3299,18 +3283,12 @@ special_insn:
                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;
@@ -3319,8 +3297,6 @@ special_insn:
                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) {
@@ -3330,9 +3306,6 @@ special_insn:
                break;
        case 0xcf:              /* iret */
                rc = emulate_iret(ctxt, ops);
-
-               if (rc != X86EMUL_CONTINUE)
-                       goto done;
                break;
        case 0xd0 ... 0xd1:     /* Grp2 */
                emulate_grp2(ctxt);
@@ -3419,8 +3392,6 @@ special_insn:
                break;
        case 0xf6 ... 0xf7:     /* Grp3 */
                rc = emulate_grp3(ctxt, ops);
-               if (rc != X86EMUL_CONTINUE)
-                       goto done;
                break;
        case 0xf8: /* clc */
                ctxt->eflags &= ~EFLG_CF;
@@ -3453,8 +3424,6 @@ special_insn:
        case 0xfe: /* Grp4 */
        grp45:
                rc = emulate_grp45(ctxt, ops);
-               if (rc != X86EMUL_CONTINUE)
-                       goto done;
                break;
        case 0xff: /* Grp5 */
                if (c->modrm_reg == 5)
@@ -3464,6 +3433,9 @@ special_insn:
                goto cannot_emulate;
        }
 
+       if (rc != X86EMUL_CONTINUE)
+               goto done;
+
 writeback:
        rc = writeback(ctxt, ops);
        if (rc != X86EMUL_CONTINUE)
@@ -3545,8 +3517,6 @@ twobyte_insn:
                                switch (c->modrm_rm) {
                                case 1:
                                        rc = kvm_fix_hypercall(ctxt->vcpu);
-                                       if (rc != X86EMUL_CONTINUE)
-                                               goto done;
                                        break;
                                default:
                                        goto cannot_emulate;
@@ -3585,10 +3555,6 @@ twobyte_insn:
                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);
@@ -3665,17 +3631,9 @@ twobyte_insn:
                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;
@@ -3694,8 +3652,6 @@ twobyte_insn:
                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 */
@@ -3713,8 +3669,6 @@ twobyte_insn:
                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 */
@@ -3745,8 +3699,6 @@ twobyte_insn:
                break;
        case 0xb2:              /* lss */
                rc = emulate_load_segment(ctxt, ops, VCPU_SREG_SS);
-               if (rc != X86EMUL_CONTINUE)
-                       goto done;
                break;
        case 0xb3:
              btr:              /* btr */
@@ -3754,13 +3706,9 @@ twobyte_insn:
                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;
@@ -3825,12 +3773,14 @@ twobyte_insn:
                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: