[svn-r8667] Purpose:

    Code optimization

Description:
    Restructure conversion loop of variable-length objects to avoid walking
through memory backwards and allocating as many temporary buffers.  (This uses
the optimized method used in the atomic type conversions).
    Also bring back another optimization for variable-length datatypes that
avoids querying the DXPL so many times.

Platforms tested:
    Solaris 2.7 (arabica)
    FreeBSD 4.10 (sleipnir) w/parallel
    Too minor to require h5committest

1 files changed, 34 insertions, 33 deletions

diff --git a/src/H5Tpkg.h b/src/H5Tpkg.h
index 7d891e7..2a72f93 100644
--- a/src/H5Tpkg.h
+++ b/src/H5Tpkg.h
@@ -37,6 +37,7 @@
 /* Get package's private header */
 #include "H5Tprivate.h"
 
+/* Other private headers needed by this file */
 #include "H5Dprivate.h"		/* Datasets				*/
 #include "H5Fprivate.h"		/* Files				*/
 #include "H5HGprivate.h"	/* Global heaps				*/
@@ -60,11 +61,11 @@ struct H5T_stats_t {
     H5_timer_t	timer;			/*total time for conversion	     */
 };
 
-/* The data type conversion database */
+/* The datatype conversion database */
 struct H5T_path_t {
     char	name[H5T_NAMELEN];	/*name for debugging only	     */
-    H5T_t	*src;			/*source data type ID		     */
-    H5T_t	*dst;			/*destination data type ID	     */
+    H5T_t	*src;			/*source datatype ID		     */
+    H5T_t	*dst;			/*destination datatype ID	     */
     H5T_conv_t	func;			/*data conversion function	     */
     hbool_t	is_hard;		/*is it a hard function?	     */
     hbool_t	is_noop;		/*is it the noop conversion?	     */
@@ -72,14 +73,6 @@ struct H5T_path_t {
     H5T_cdata_t	cdata;			/*data for this function	     */
 };
 
-/* VL types */
-typedef enum {
-    H5T_VLEN_BADTYPE =  -1, /* invalid VL Type */
-    H5T_VLEN_SEQUENCE=0,    /* VL sequence */
-    H5T_VLEN_STRING,        /* VL string */
-    H5T_VLEN_MAXTYPE        /* highest type (Invalid as true type) */
-} H5T_vlen_type_t;
-
 typedef struct H5T_atomic_t {
     H5T_order_t		order;	/*byte order				     */
     size_t		prec;	/*precision in bits			     */
@@ -113,14 +106,14 @@ typedef struct H5T_atomic_t {
     } u;
 } H5T_atomic_t;
 
-/* How members are sorted for compound or enum data types */
+/* How members are sorted for compound or enum datatypes */
 typedef enum H5T_sort_t {
     H5T_SORT_NONE	= 0,		/*not sorted			     */
     H5T_SORT_NAME	= 1,		/*sorted by member name		     */
     H5T_SORT_VALUE	= 2 		/*sorted by memb offset or enum value*/
 } H5T_sort_t;
 
-/* A compound data type */
+/* A compound datatype */
 typedef struct H5T_compnd_t {
     int		nalloc;		/*num entries allocated in MEMB array*/
     int		nmembs;		/*number of members defined in struct*/
@@ -129,22 +122,30 @@ typedef struct H5T_compnd_t {
     struct H5T_cmemb_t	*memb;	/*array of struct members	     */
 } H5T_compnd_t;
 
-/* An enumeration data type */
+/* An enumeration datatype */
 typedef struct H5T_enum_t {
     int		nalloc;		/*num entries allocated		     */
     int		nmembs;		/*number of members defined in enum  */
-    H5T_sort_t		sorted;		/*how are members sorted?	     */
-    uint8_t		*value;		/*array of values		     */
-    char		**name;		/*array of symbol names		     */
+    H5T_sort_t	sorted;		/*how are members sorted?	     */
+    uint8_t	*value;		/*array of values		     */
+    char	**name;		/*array of symbol names		     */
 } H5T_enum_t;
 
 /* VL function pointers */
 typedef hssize_t (*H5T_vlen_getlenfunc_t)(void *vl_addr);
 typedef htri_t (*H5T_vlen_isnullfunc_t)(H5F_t *f, void *vl_addr);
 typedef herr_t (*H5T_vlen_readfunc_t)(H5F_t *f, hid_t dxpl_id, void *_vl, void *buf, size_t len);
-typedef herr_t (*H5T_vlen_writefunc_t)(H5F_t *f, hid_t dxpl_id, void *_vl, void *buf, void *_bg, hsize_t seq_len, hsize_t base_size);
+typedef herr_t (*H5T_vlen_writefunc_t)(H5F_t *f, hid_t dxpl_id, const H5T_vlen_alloc_info_t *vl_alloc_info, void *_vl, void *buf, void *_bg, hsize_t seq_len, hsize_t base_size);
 typedef herr_t (*H5T_vlen_setnullfunc_t)(H5F_t *f, hid_t dxpl_id, void *_vl, void *_bg);
 
+/* VL types */
+typedef enum {
+    H5T_VLEN_BADTYPE =  -1, /* invalid VL Type */
+    H5T_VLEN_SEQUENCE=0,    /* VL sequence */
+    H5T_VLEN_STRING,        /* VL string */
+    H5T_VLEN_MAXTYPE        /* highest type (Invalid as true type) */
+} H5T_vlen_type_t;
+
 /* A VL datatype */
 typedef struct H5T_vlen_t {
     H5T_vlen_type_t     type;   /* Type of VL data in buffer */
@@ -160,16 +161,16 @@ typedef struct H5T_vlen_t {
     H5T_vlen_setnullfunc_t setnull; /* Function to set a VL value to NIL */
 } H5T_vlen_t;
 
-/* An opaque data type */
+/* An opaque datatype */
 typedef struct H5T_opaque_t {
     char		*tag;		/*short type description string	     */
 } H5T_opaque_t;
 
 /* An array datatype */
 typedef struct H5T_array_t {
-    size_t		nelem;		/* total number of elements in array */
+    size_t	nelem;		/* total number of elements in array */
     int		ndims;		/* member dimensionality        */
-    size_t		dim[H5S_MAX_RANK];  /* size in each dimension       */
+    size_t	dim[H5S_MAX_RANK];  /* size in each dimension       */
     int		perm[H5S_MAX_RANK]; /* index permutation            */
 } H5T_array_t;
 
@@ -187,19 +188,19 @@ struct H5T_t {
     H5F_t		*sh_file;/*file pointer if this is a shared type     */
     H5T_class_t		type;	/*which class of type is this?		     */
     size_t		size;	/*total size of an instance of this type     */
-    hbool_t     force_conv;     /* Set if this type always needs to be converted and H5T_conv_noop cannot be called */
-    struct H5T_t	*parent;/*parent type for derived data types	     */
+    hbool_t		force_conv;/* Set if this type always needs to be converted and H5T_conv_noop cannot be called */
+    struct H5T_t	*parent;/*parent type for derived datatypes	     */
     union {
-        H5T_atomic_t	atomic; /* an atomic data type              */
-        H5T_compnd_t	compnd; /* a compound data type (struct)    */
-        H5T_enum_t	    enumer; /* an enumeration type (enum)       */
-        H5T_vlen_t	    vlen;   /* a variable-length datatype       */
-        H5T_opaque_t	opaque; /* an opaque data type              */
-        H5T_array_t	    array;  /* an array datatype                */
+        H5T_atomic_t	atomic; /* an atomic datatype              */
+        H5T_compnd_t	compnd; /* a compound datatype (struct)    */
+        H5T_enum_t	enumer; /* an enumeration type (enum)       */
+        H5T_vlen_t	vlen;   /* a variable-length datatype       */
+        H5T_opaque_t	opaque; /* an opaque datatype              */
+        H5T_array_t	array;  /* an array datatype                */
     } u;
 };
 
-/* A compound data type member */
+/* A compound datatype member */
 typedef struct H5T_cmemb_t {
     char		*name;		/*name of this member		     */
     size_t		offset;		/*offset from beginning of struct    */
@@ -210,8 +211,8 @@ typedef struct H5T_cmemb_t {
 /* The master list of soft conversion functions */
 typedef struct H5T_soft_t {
     char	name[H5T_NAMELEN];	/*name for debugging only	     */
-    H5T_class_t src;			/*source data type class	     */
-    H5T_class_t dst;			/*destination data type class	     */
+    H5T_class_t src;			/*source datatype class	     */
+    H5T_class_t dst;			/*destination datatype class	     */
     H5T_conv_t	func;			/*the conversion function	     */
 } H5T_soft_t;
 
@@ -860,7 +861,7 @@ H5_DLL ssize_t H5T_bit_find(uint8_t *buf, size_t offset, size_t size,
 H5_DLL htri_t H5T_bit_inc(uint8_t *buf, size_t start, size_t size);
 
 /* VL functions */
-H5_DLL H5T_t * H5T_vlen_create(H5T_t *base);
+H5_DLL H5T_t * H5T_vlen_create(const H5T_t *base);
 
 /* Array functions */
 H5_DLL H5T_t * H5T_array_create(H5T_t *base, int ndims,