7085 add support for "if" and "else" statements in dtrace

*** 23,33 ****
   * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
  /*
!  * Copyright (c) 2013 by Delphix. All rights reserved.
   * Copyright (c) 2013, Joyent, Inc. All rights reserved.
   */
  
  #ifndef _DTRACE_H
  #define _DTRACE_H
--- 23,33 ----
   * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
  /*
!  * Copyright (c) 2014 by Delphix. All rights reserved.
   * Copyright (c) 2013, Joyent, Inc. All rights reserved.
   */
  
  #ifndef _DTRACE_H
  #define _DTRACE_H
*** 53,62 ****
--- 53,63 ----
   */
  
  #define DTRACE_VERSION  3               /* library ABI interface version */
  
  struct ps_prochandle;
+ struct dt_node;
  typedef struct dtrace_hdl dtrace_hdl_t;
  typedef struct dtrace_prog dtrace_prog_t;
  typedef struct dtrace_vector dtrace_vector_t;
  typedef struct dtrace_aggdata dtrace_aggdata_t;
  
*** 109,119 ****
  #define DTRACE_C_ZDEFS  0x0004  /* Permit probe defs that match zero probes */
  #define DTRACE_C_EATTR  0x0008  /* Error if program attributes less than min */
  #define DTRACE_C_CPP    0x0010  /* Preprocess input file with cpp(1) utility */
  #define DTRACE_C_KNODEF 0x0020  /* Permit unresolved kernel symbols in DIFO */
  #define DTRACE_C_UNODEF 0x0040  /* Permit unresolved user symbols in DIFO */
! #define DTRACE_C_PSPEC  0x0080  /* Intepret ambiguous specifiers as probes */
  #define DTRACE_C_ETAGS  0x0100  /* Prefix error messages with error tags */
  #define DTRACE_C_ARGREF 0x0200  /* Do not require all macro args to be used */
  #define DTRACE_C_DEFARG 0x0800  /* Use 0/"" as value for unspecified args */
  #define DTRACE_C_NOLIBS 0x1000  /* Do not process D system libraries */
  #define DTRACE_C_CTL    0x2000  /* Only process control directives */
--- 110,120 ----
  #define DTRACE_C_ZDEFS  0x0004  /* Permit probe defs that match zero probes */
  #define DTRACE_C_EATTR  0x0008  /* Error if program attributes less than min */
  #define DTRACE_C_CPP    0x0010  /* Preprocess input file with cpp(1) utility */
  #define DTRACE_C_KNODEF 0x0020  /* Permit unresolved kernel symbols in DIFO */
  #define DTRACE_C_UNODEF 0x0040  /* Permit unresolved user symbols in DIFO */
! #define DTRACE_C_PSPEC  0x0080  /* Interpret ambiguous specifiers as probes */
  #define DTRACE_C_ETAGS  0x0100  /* Prefix error messages with error tags */
  #define DTRACE_C_ARGREF 0x0200  /* Do not require all macro args to be used */
  #define DTRACE_C_DEFARG 0x0800  /* Use 0/"" as value for unspecified args */
  #define DTRACE_C_NOLIBS 0x1000  /* Do not process D system libraries */
  #define DTRACE_C_CTL    0x2000  /* Only process control directives */
*** 517,526 ****
--- 518,531 ----
      const char *, dtrace_typeinfo_t *);
  
  extern int dtrace_type_fcompile(dtrace_hdl_t *,
      FILE *, dtrace_typeinfo_t *);
  
+ extern struct dt_node *dt_compile_sugar(dtrace_hdl_t *,
+     struct dt_node *);
+ 
+ 
  /*
   * DTrace Probe Interface
   *
   * Library clients can use these functions to iterate over the set of available
   * probe definitions and inquire as to their attributes.  The probe iteration