|
Programming Interface Information:
This information is NOT
intended to be
used as Programming Interfaces of VM/ESA. It is to be used for diagnosis only. |
SYMTB
Cross Reference (Contains links to field and bit definitions)
SYMTB Prolog
NAME : HCPSYMTB
DESCRIPTION: Symbol Table Entry
STATUS : VM/ESA Version 2, Release 1.0
DSECT : SYMTB
FUNCTION : The Symbol Table Entry contains information to
describe the location, size and (possibly) attributes
of CP external labels.
LOCATED BY : SYMPT, LOCATE process pointer blocks.
CREATED BY : HCPCFD as a result of a dynamic load as a result
of CPXLOAD.
HCPLDR during the CP nucleus build process.
DELETED BY : HCPCFD as a result of a dynamic unload of executable
code.
REFERENCES : None
SERIALIZED : Additions or changes to the SYMTB entries is controlled
by the SYMLHLCK lock.
NOTES : SYMTB entries never exist alone, they are always part
of @MAPSTRT-@MAPEND set of SYMTB entries, or are part
of a page of SYMTB entries created by HCPCFDAD during
normal system operation as a result of CPXLOAD.
SYMTB Control Block Content
SYMTB DSECT
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure SYMTB Symbol Table Entry 0000 0 Character 8 SYMTBNM Symbol name 0008 8 Address 4 SYMTBVA Virtual address in CP 000C 12 Bitstring 1 SYMTBF0 Flags 1... .... SYMTBF0L X'80' Added by HCPCFDAD 000D 13 Signed 3 SYMTBLN Length (if CSECT), else 0 The SYMTB described up to this point is the portion (16 bytes) of the SYMTB built by HCPLDR and cannot be changed unless HCPLDR is radically changed. The only way to realize that no additional fields exist is to realize that this SYMTB is located by the first SYMPT pointer block that is chained from the SYMLH Locate Header Block. SYMTBSSZ is the length of these static entries built by HCPLDR. 00000010 SYMTBSSZ *-SYMTB Length of SYMTB entries . for @MAPSTRT entries These additional fields are built only for SYMTB entries added during normal system operation by HCPCFDAD when new external labels come into existence, like during dynamic loading of executable code from CMS files. The way to realize that these additional fields exist is to test SYMTBF0.SYMTBF0L, which indicates that this SYMTB describes external labels in dynamically loaded modules. 0010 16 Bitstring 1 SYMTBF1 Flags 0011 17 Bitstring 1 SYMTBF2 Flags 0012 18 Bitstring 1 SYMTBF3 Flags 0013 19 Bitstring 1 SYMTBF4 Flags .1.. .... SYMTBF4T X'40' Loaded TEMPORARY SYMTBDSZ is the length of the dynamic entries built by HCPCFD. 0014 20 Signed 4 * (0) Assure fullword alignment 00000014 SYMTBDSZ *-SYMTB Length of SYMTB entries . for dynamic entries
SYMTB Storage Layout
*** SYMTB - Symbol Table Entry * * +-------------------------------------------------------+ * 0 | SYMTBNM | * +---------------------------+------+--------------------+ * 8 | SYMTBVA |:TBF0 | SYMTBLN | * +------+------+------+------+------+--------------------+ * 10 |:TBF1 |:TBF2 |:TBF3 |:TBF4 | 14 * +------+------+------+------+ * *** SYMTB - Symbol Table Entry
SYMTB Cross Reference
(contains links to field and bit definitions)Symbol Dspl Value -------------- ---- -----SYMTBDSZ 0014 00000014
SYMTBF0 000C
SYMTBF0L 000C 80
SYMTBF1 0010
SYMTBF2 0011
SYMTBF3 0012
SYMTBF4 0013
SYMTBF4T 0013 40
SYMTBLN 000D
SYMTBNM 0000
SYMTBSSZ 000D 00000010
SYMTBVA 0008
Last updated on 3 Aug 1999 at 12:37:24 EDT.
Copyright IBM Corporation, 1990, 1999